TY - JOUR
TI - Solution of dense linear systems via roundoff-error-free factorization algorithms: Theoretical connections and computational comparisons
AU - Escobedo, A.R.
AU - Moreno-Centeno, E.
AU - Lourenco, C.
T2 - ACM Transactions on Mathematical Software
AB - Exact solving of systems of linear equations (SLEs) is a fundamental subroutine within number theory, formal verification of mathematical proofs, and exact-precision mathematical programming. Moreover, efficient exact SLE solution methods could be valuable for a growing body of science and engineering applications where current fixed-precision standards have been deemed inadequate. This article contains key derivations relating, and computational tests comparing, two exact direct solution frameworks: roundoff-error-free (REF) LU factorization and rational arithmetic LU factorization. Specifically, both approaches solve the linear system Ax = b by factoring the matrix A into the product of a lower triangular (L) and upper triangular (U) matrix, A = LU . Most significantly, the featured findings reveal that the integer-preserving REF factorization framework solves dense SLEs one order of magnitude faster than the exact rational arithmetic approach while requiring half the memory. Since rational LU is utilized for basic solution validation in exact linear and mixed-integer programming, these results offer preliminary evidence of the potential of the REF factorization framework to be utilized within this specific context. Additionally, this article develops and analyzes an efficient streamlined version of Edmonds’s Q-matrix approach that can be implemented as another basic solution validation approach. Further experiments demonstrate that the REF factorization framework also outperforms this alternative integer-preserving approach in terms of memory requirements and computational effort. General purpose codes to solve dense SLEs exactly via any of the aforementioned methods have been made available to the research and academic communities.
DA - 2018///
PY - 2018///
DO - 10.1145/3199571
VL - 44
IS - 4
SP - 1-24
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85060552334&partnerID=MN8TOARS
ER -
TY - CONF
TI - Bus-Angle Difference Structural Cuts for Transmission System Expansion Planning with L-l Reliability
AU - Escobar, L.M.
AU - Escobedo, A.R.
AU - Escobar, D.
AU - Romero, R.
AB - This paper presents a methodology to solve the long-term transmission network expansion planning problem considering L-l reliability. The methodology supplements an underlying mixed-integer linear programming formulation with cutting planes derived from structural insights of bus-angle differences involving buses connected by paths of existing and/or expansion lines. The addition of these cutting planes expedites the solution process by yielding tighter relaxation bounds within a branch-and-cut framework, thereby reducing computational times and memory requirements. In order to solve the resulting problems, this work uses the AMPL modeling language interfaced with the CPLEX mathematical programming solver. The practicality of the methodology is tested via the Southern Brazilian System, yielding very promising results.
C2 - 2018///
C3 - 2018 IEEE Electrical Power and Energy Conference, EPEC 2018
DA - 2018///
DO - 10.1109/EPEC.2018.8598449
PB - IEEE
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85061935375&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Method and system to automatically generate throughput for semiconductor tools
DA - 2018/1/1/
PY - 2018/1/1/
ER -
TY - JOUR
TI - A bi-criteria model for closed loop supply chain network design
AU - Pazhani, Subramanian
AU - Ravindran, A. Ravi
T2 - International Journal of Operational Research
AB - Closed loop supply chains (CLSC) are the integration of both forward and reverse supply chains. The integration is important as independent operations and management of forward and reverse supply chains lead to a reduction in efficiency in the supply chain as a whole. This article considers a four-stage CLSC network with commercial returns, which could be potentially recovered by light repair operations or by refurbishing. The annual estimate of commercial returns in the USA is in excess of $100 billion. This paper discusses the optimal design of a CLSC network with the objectives of maximising the profit of the supply chain and minimising the energy usage at the warehousing facilities and energy consumed during transportation. A bi-criteria mixed integer linear programming (MILP) model is developed to determine the optimal locations of the facilities and the distribution of flows between facilities in the CLSC. We propose an interactive optimisation algorithm to systematically solve the bi-criteria problem which poses less cognitive burden on the decision maker and converges faster to the best compromise solution.
DA - 2018///
PY - 2018///
DO - 10.1504/ijor.2018.089735
VL - 31
IS - 3
SP - 330
J2 - IJOR
LA - en
OP -
SN - 1745-7645 1745-7653
UR - http://dx.doi.org/10.1504/ijor.2018.089735
DB - Crossref
ER -
TY - JOUR
TI - A bi-criteria mixed integer linear programming model for load balancing and chemical saving in wafer cleaning processes: IE: Industrial engineering
AU - Pazhani, Subramanian
AU - Beeg, Thomas
AU - Kowalczyk, Kristopher
AU - Dietrich, Todd
T2 - 2018 29th Annual SEMI Advanced Semiconductor Manufacturing Conference (ASMC)
AB - Semiconductor manufacturing or wafer fabrication process involves multiple processing steps and is highly re-entrant, where a job may visit an equipment group more than once, at various stages of the product flow. Wafer cleaning process in semiconductor fabrication comprises multiple steps at various stages of the product flow to remove particles and oxidize organic contaminants, using different chemicals. This paper focusses on front-end of the line wafer cleaning steps. We consider J equipment groups which run I clean process steps and uses M different chemicals. Each step is qualified to run on a set of equipment groups and when recipes using different chemical run back to back on a tool-there is a chemical pre-dispense to clean and condition the nozzle. Given today's increasingly cost-conscious and competitive market, this study focuses on balancing loads on the equipment groups and minimize operating cost by reducing chemical pre-dispenses. We propose a bi-criteria mixed integer linear programming model to allocate daily demands to the equipment groups with the objectives of minimizing the maximum utilization and reducing chemical pre-dispenses. We also propose a priority based dispatching algorithm to translate the model output and implement in a dispatching system. Results show that the model reduces chemical pre-dispense resulting in significant cost saving, improved throughput due to cascading, and balanced utilization across the equipment groups.
DA - 2018/4//
PY - 2018/4//
DO - 10.1109/asmc.2018.8373188
UR - http://dx.doi.org/10.1109/asmc.2018.8373188
ER -
TY - CHAP
TI - Design of a Compact Modular Marine Refrigeration Unit
AU - Koprov, Pavel
T2 - Marine Herald
PY - 2018///
ET - 1st
ER -
TY - CONF
TI - Stochastic Unit Commitment Performance Considering Monte Carlo Wind Power Scenarios
AB - Stochastic versions of the unit commitment problem have been advocated for addressing the uncertainty presented by high levels of wind power penetration. However, little work has been done to study trade-offs between computational complexity and the quality of solutions obtained as the number of probabilistic scenarios is varied. Here, we describe extensive experiments using real publicly available wind power data from the Bonneville Power Administration. Solution quality is measured by re-enacting day-ahead reliability unit commitment (which selects the thermal units that will be used each hour of the next day) and real-time economic dispatch (which determines generation levels) for an enhanced WECC-240 test system in the context of a production cost model simulator; outputs from the simulation, including cost, reliability, and computational performance metrics, are then analyzed. Unsurprisingly, we find that both solution quality and computational difficulty increase with the number of probabilistic scenarios considered. However, we find unexpected transitions in computational difficulty at a specific threshold in the number of scenarios, and report on key trends in solution performance characteristics. Our findings are novel in that we examine these tradeoffs using real-world wind power data in the context of an out-of-sample production cost model simulation, and are relevant for both practitioners interested in deploying and researchers interested in developing scalable solvers for stochastic unit commitment.
C2 - 2018/6//
C3 - 2018 IEEE International Conference on Probabilistic Methods Applied to Power Systems (PMAPS)
DA - 2018/6//
DO - 10.1109/pmaps.2018.8440563
UR - http://dx.doi.org/10.1109/pmaps.2018.8440563
ER -
TY - JOUR
TI - Electrohydrodynamic (EHD) Printing of Molten Metal Ink for Flexible and Stretchable Conductor with Self‐Healing Capability
AU - Han, Yiwei
AU - Dong, Jingyan
T2 - Advanced Materials Technologies
AB - Abstract Direct printing of flexible and stretchable conductors provides a low‐cost mask‐less approach for the fabrication of next‐generation electronics. In this work, an electrohydrodynamic (EHD) printing technology is studied to achieve high‐resolution printing of low‐melting‐point metal alloys, which enables low‐cost direct fabrication of metallic conductors with sub 50 µm resolution. The EHD printed microscale metallic conductors represent a promising way to create conductive paths with metallic conductivity and excellent flexibility and stretchability. A stable electrical response is achieved after hundreds of bending cycles and during stretching/releasing cycles in a large range of tensile strain (0–70%) for the printed conductors with properly designed 2D patterns. Due to the low melting point of the metal alloy ink, the printed conductor demonstrates self‐healing capability that recovers from failure simply by heating the device above the eutectic temperature of the metal ink and applying slight pressure. A high‐density touch sensor array is fabricated to demonstrate the high‐resolution capability of the EHD printing for the direction fabrication of flexible and stretchable devices.
DA - 2018/3//
PY - 2018/3//
DO - 10.1002/admt.201700268
VL - 3
IS - 3
UR - https://doi.org/10.1002/admt.201700268
KW - direct metal printing
KW - electrohydrodynamic (EHD) printing
KW - flexible and stretchable electronics
KW - printed electronics
KW - self-healing circuits
ER -
TY - CONF
TI - Production Planning Models with Chance Constraints and Advance Demand Information
AU - Ziarnetzky, T.
AU - Monch, L.
AU - Uzsoy, R.
T2 - IISE Annual Conference
C2 - 2018/5//
CY - Orlando, FL
DA - 2018/5//
PY - 2018/5//
ER -
TY - CONF
TI - Coordinating Capacity Negotiations In Semiconductor Industry
AU - Bansal, A.
AU - Uzsoy, R.
AU - Kempf, K.G.
T2 - INFORMS National Meeting
C2 - 2018/11//
CY - Phoenix, AZ
DA - 2018/11//
PY - 2018/11//
ER -
TY - CONF
TI - Modeling for the Equitable and Effective Distribution of Food Donations Under Stochastic Capacities
AU - Sengul Orgut, I.
AU - Ivy, J.S.
AU - Uzsoy, R.
T2 - INFORMS National Meeting
C2 - 2018/11//
CY - Phoenix, AZ
DA - 2018/11//
PY - 2018/11//
ER -
TY - CONF
TI - Robust Optimization Approaches for the Equitable and Effective Distribution of Donated Food
AU - Sengul Orgut, I.
AU - Ivy, J.S.
AU - Uzsoy, R.
AU - Hale, C.
T2 - INFORMS National Meeting
C2 - 2018/11//
CY - Phoenix, AZ
DA - 2018/11//
PY - 2018/11//
ER -
TY - JOUR
TI - Vibration Study of Novel Compliant Needle used for Vibration-assisted Needle Insertion
AU - Cai, Yi
AU - Moore, Jason
AU - Lee, Yuan-Shin
T2 - Computer-Aided Design and Applications
DA - 2018/11/28/
PY - 2018/11/28/
DO - 10.14733/cadaps.2019.742-754
VL - 16
IS - 4
SP - 742-754
UR - https://doi.org/10.14733/cadaps.2019.742-754
ER -
TY -
ER -
TY -
ER -
TY -
ER -
TY - SOUND
TI - A Review of Product Ramping Models in Semiconductor Manufacturing
AU - Manda, A.B.
AU - Uzsoy, R.
DA - 2018/11//
PY - 2018/11//
ER -
TY - SOUND
TI - Planning Releases During Product Transitions in Semiconductor Manufacturing
AU - Manda, A.B.
AU - Uzsoy, R.
DA - 2018/11//
PY - 2018/11//
ER -
TY - SOUND
TI - Conic Reformulations of Production Planning Problems with Clearing Functions
AU - Gopalswamy, K.
AU - Uzsoy, R.
DA - 2018/11//
PY - 2018/11//
ER -
TY - JOUR
TI - Production Planning and Engineering Process Improvement
AU - Medhin, N.
AU - Uzsoy, R.
T2 - Communications in Applied Analysis
DA - 2018///
PY - 2018///
VL - 22
IS - 4
SP - 583–596
ER -
TY - JOUR
TI - Editorial 2017 Best Paper Award
AU - Uzsoy, Reha
T2 - IEEE Transactions on Semiconductor Manufacturing
AB - Each year the Transactions on Semiconductor Manufacturing recognizes the best paper published during the previous calendar year. This year 9 papers were nominated by our reviewers and members of our Editorial Board and Steering Committee, out of a total of 78 papers published in our pages in 2017. From among these, the members of the Editorial Board and Steering Committee selected the paper entitled “A Novel Dynamic Process Control Scheme to Improve Cycle Time in Fabs” by Dr. Michael Hassoun of the Department of Industrial Engineering and Management of Ariel University in Israel. This paper continues an ongoing line of research examining the impact of process control policies on the tradeoff between cycle time and yield in wafer fabrication. The primary finding is that modest relaxation of process control parameters to reduce time spent adjusting production equipment when it is in high demand can often reduce cycle time with minimal negative impact. A number of fruitful extensions for future work are also discussed, holding out the possibility of improved integration of scheduling and process control techniques. On behalf of the TSM community, I have the pleasure of congratulating Dr. Hassoun on this recognition, and of wishing him continued success in future.
DA - 2018/8//
PY - 2018/8//
DO - 10.1109/TSM.2018.2852818
VL - 31
IS - 3
SP - 325-325
UR - https://doi.org/10.1109/TSM.2018.2852818
ER -
TY - CONF
TI - Real-Time Predictive Analytics Using Degradation Image Data
AU - Fang, X.
AU - Paynabar, K.
AU - Gebraeel, N.
AB - Prognostics by using degradation image streams is challenging due to the high-dimensionality and complex spatial-temporal structure of images. In this paper, we proposed a penalized (log)-location-scale regression model that can utilize high dimensional tensors to predict the residual useful lifetime of systems. Our method first reduces the dimensionality of tensor covariates by projecting them onto a low tensor space. Next, the coefficient tensor is decomposed by utilizing CANDECOMP/PARAFAC (CP) decomposition. The decomposition facilitates further dimension reduction of coefficient tensors. By doing so, the number of parameters to be estimated is dramatically reduced. Furthermore, a numerical algorithm with global convergence property was developed for the model estimation.
C2 - 2018///
C3 - Proceedings - Annual Reliability and Maintainability Symposium
DA - 2018///
DO - 10.1109/RAM.2018.8463083
VL - 2018-January
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85054152775&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Learning Framework of Multimodal Gaussian-Bernoulli RBM Handling Real-value Input Data
AU - Choo, Sanghyun
AU - Lee, Hyunsoo
T2 - Neurocomputing
AB - Abstract The conventional Gaussian–Bernoulli restricted Boltzmann machine (GBRBM), which is a RBM model for processing real-valued data, presumes single Gaussian distribution for learning real numbers. However, a single distribution is not able to effectively reflect complex data in many cases of real applications. In order to overcome this limitation, Gaussian mixture model (GMM) based RBM is proposed. As a learning mechanism for the proposed model, an energy function handling multi-modal distribution is provided. Then, a memetic algorithm (MA) was applied in order to train the proposed framework more accurately in real-valued input data. In order to show the effectiveness of the proposed framework, the method is applied to image reconstructions. The experiments show that the proposed framework provides more valid results than the other RBM based models in reconstruction error. Through the experiment results, it is concluded that the proposed framework is able to apply real-valued input data extensively and reduce difficulties of learning parameters by capturing the characteristics of real-value input data using GMM.
DA - 2018/1/31/
PY - 2018/1/31/
DO - 10.1016/j.neucom.2017.10.018
VL - 275
IS - 1
SP - 1813–1822
UR - https://doi.org/10.1016/j.neucom.2017.10.018
KW - Multi-modal Gaussian-Bernoulli restricted Boltzmann machine (MGBRBM)
KW - Gaussian mixture model (GMM)
KW - Gaussian-Bernoulli restricted Boltzmann machine (GBRBM)
KW - Memetic algorithm
KW - Real-valued input data
ER -
TY - CONF
TI - A simulation model to assess the impact of insurance expansion on colorectal cancer screening at the population level
AU - Nambiar, Siddhartha
AU - Mayorga, Maria E
AU - O’Leary, Meghan C
AU - Lich, Kristen Hassmiller
AU - Wheeler, Stephanie B
T2 - IEEE Press
C2 - 2018///
C3 - Proceedings of the 2018 Winter Simulation Conference
DA - 2018///
SP - 2701-2712
ER -
TY - JOUR
TI - L1-norm based Major Component Detection and Analysis for Asymmetric Radial Data
AU - An, Q.
AU - Fang, S-C
AU - Jiang, S.
AU - Lavery, J.E.
T2 - International Journal of Operations Research
DA - 2018///
PY - 2018///
DO - 10.6886/IJOR.201809_15(3).0001
VL - 15
SP - 89–100
ER -
TY - CONF
TI - The Distracted Worker: Effect on Hazard Recognition and Safety Performance
AU - Namian, Mostafa
AU - Albert, Alex
AU - Feng, Jing
T2 - Construction Research Congress 2018
AB - Hazard recognition is an essential element for successful accident and injury prevention. However, studies have revealed that construction workers fail to identify a large proportion of hazards in their workplaces. Therefore, understanding factors that adversely affect hazard recognition performance is a fundamental step towards improving safety performance. Given the unique, complex, and dynamic nature of construction operations, past research has provided anecdotal evidence suggesting that distraction may be correlated to undesirable safety outcomes such as injuries. For example, Hinze’s distraction theory suggests that workers are more likely to be involved in an accident while they are distracted. However, these theoretical propositions have not been empirically tested. To address this knowledge gap, the objective of this research was to test the hypothesis that distracted workers will identify fewer hazards than undistracted workers. To test the hypothesis, an experiment was conducted with 70 construction workers where the participants were randomly assigned to a distracted or an undistracted group. Sixteen pre-selected case images, representing real construction operations, were used to evaluate the hazard recognition performance of the workers. For the distracted group, distraction was induced using visual stimuli presented as unrelated video clips during the hazard recognition activity. The data analysis results showed that the distracted workers recognized a smaller proportion of hazards than the undistracted workers (p-value = 0.003). The research findings indicate that reducing workplace distractions can be a useful intervention to improve the safety performance of construction workers such as hazard recognition levels.
C2 - 2018/3/29/
C3 - Construction Research Congress 2018
CY - New Orleans, Louisiana
DA - 2018/3/29/
PY - 2018/4/2/
DO - 10.1061/9780784481288.036
PB - American Society of Civil Engineers
SN - 9780784481288
UR - http://dx.doi.org/10.1061/9780784481288.036
ER -
TY - JOUR
TI - The impacts of perceptual load and driving duration on mind wandering in driving
AU - Geden, Michael
AU - Staicu, Ana-Maria
AU - Feng, Jing
T2 - Transportation Research Part F: Traffic Psychology and Behaviour
AB - A significant portion of the risk of driver distraction comes from the cognitive consequences of attention deviating from the current task. While distraction can be due to external stimulations such as flashing billboards or a ringing phone, simply engaging in internally-generated task-unrelated thoughts (i.e., mind wandering) could raise one’s crash risk as well. Compared to the extensive efforts in recent years to understand the mechanisms of external distraction, relatively little is known about internal distraction such as mind wandering. This study investigated how perceptual load and driving duration can impact both the rate of mind wandering and its costs on drivers’ performance in vehicular control. Generalized additive mixed effects models were used to estimate these effects in both a lower perceptual load scenario and a higher perceptual load scenario in simulated driving. Our study found that, under a higher perceptual load, participants’ minds wandered less often. Significant nonlinear effects for driving duration were found on vehicular control during mind wandering for both perceptual load conditions, while the effect of driving duration was linear for on-task periods. These results suggest that, while mind wandering, individuals’ driving performance fluctuates greatly, which has significant implications on driving safety for individual drivers and overall traffic flow.
DA - 2018/8//
PY - 2018/8//
DO - 10.1016/J.TRF.2017.07.004
VL - 57
SP - 75-83
J2 - Transportation Research Part F: Traffic Psychology and Behaviour
LA - en
OP -
SN - 1369-8478
UR - http://dx.doi.org/10.1016/J.TRF.2017.07.004
DB - Crossref
KW - Mind wandering
KW - Driving
KW - Distraction
KW - Generalized additive modeling
KW - Mixed effects modeling
KW - Perceptual load
KW - Driving duration
ER -
TY - JOUR
TI - ℓ1-Norm Based Central Point Analysis for Asymmetric Radial Data
AU - An, Qi
AU - Fang, Shu-Cherng
AU - Nie, Tiantian
AU - Jiang, Shan
T2 - Annals of Data Science
DA - 2018/1/29/
PY - 2018/1/29/
DO - 10.1007/S40745-018-0147-2
VL - 5
IS - 3
SP - 469–486
SN - 2198-5804 2198-5812
UR - http://dx.doi.org/10.1007/S40745-018-0147-2
ER -
TY - JOUR
TI - Development of a signal-head-free intersection control logic in a fully connected and autonomous vehicle environment
AU - Mirheli, A.
AU - Hajibabai, L.
AU - Hajbabaie, A.
T2 - Transportation Research Part C: Emerging Technologies
AB - Establishment of effective cooperation between vehicles and transportation infrastructure improves travel reliability in urban transportation networks. Lack of collaboration, however, exacerbates congestion due mainly to frequent stops at signalized intersections. It is beneficial to develop a control logic that collects basic safety message from approaching connected and autonomous vehicles and guarantees efficient intersection operations with safe and incident free vehicle maneuvers. In this paper, a signal-head-free intersection control logic is formulated into a dynamic programming model that aims to maximize the intersection throughput. A stochastic look-ahead technique is proposed based on Monte Carlo tree search algorithm to determine the near-optimal actions (i.e., acceleration rates) over time to prevent movement conflicts. Our numerical results confirm that the proposed technique can solve the problem efficiently and addresses the consequences of existing traffic signals. The proposed approach, while completely avoids incidents at intersections, significantly reduces travel time (ranging between 59.4% and 83.7% when compared to fixed-time and fully-actuated control strategies) at intersections under various demand patterns.
DA - 2018///
PY - 2018///
DO - 10.1016/j.trc.2018.04.026
VL - 92
SP - 412-425
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85047272483&partnerID=MN8TOARS
KW - Control logic
KW - Autonomous intersection control
KW - Monte Carlo tree search
KW - Look-ahead model
KW - Connected and autonomous vehicles
KW - Dynamic programming
ER -
TY - JOUR
TI - Optimal design of the seasonal influenza vaccine with manufacturing autonomy
AU - Özaltin, O.Y.
AU - Prokopyev, O.A.
AU - Schaefer, A.J.
T2 - INFORMS Journal on Computing
AB - AboutSectionsView PDF ToolsAdd to favoritesDownload CitationsTrack CitationsPermissionsReprints ShareShare onFacebookTwitterLinked InEmail Go to Section HomeINFORMS Journal on ComputingVol. 30, No. 2 Optimal Design of the Seasonal Influenza Vaccine with Manufacturing AutonomyOsman Y. Özaltın , Oleg A. Prokopyev , Andrew J. Schaefer Osman Y. Özaltın , Oleg A. Prokopyev , Andrew J. Schaefer Published Online:25 May 2018https://doi.org/10.1287/ijoc.2017.0786AbstractInfluenza (flu) is a serious public health concern. The first line of defense is the flu shot, whose composition is updated annually to adjust for frequent mutations of the circulating viruses. The World Health Organization recommends which strains to include in the flu shot based on global surveillance. Vaccine manufacturers produce trivalent and quadrivalent flu shots. The design of the flu shot, however, affects the manufacturers’ capacity and profit. In return, production decisions of the manufacturers affect the societal vaccination benefit by determining coverage and timely availability. We model this two-level hierarchy using a bilevel multistage stochastic mixed-integer program. Calibrated with publicly available data, our model integrates the flu shot composition and manufacturing in a stochastic and dynamic environment. We derive a branch-and-price algorithm to find the global optimal solution. We also propose an effective heuristic to provide the public health planners with a decision aid tool. Finally, we perform numerical experiments to answer important public health policy questions and to quantify the impact of the proposed modeling extensions. A major conclusion of our work is that the vaccine strain of a category that is not expected to be very prevalent and/or that is unlikely to drift in the upcoming season should be selected as early as possible, especially when the selections for other strain categories have to be postponed to improve the flu shot design.The online appendix is available at https://doi.org/10.1287/ijoc.2017.0786. Previous Back to Top Next FiguresReferencesRelatedInformationCited byManaging Product Transitions: A Bilevel Programming ApproachRahman Khorramfar, Osman Y. ÖzaltınKarl G. Kempf, Reha Uzsoy30 June 2022 | INFORMS Journal on Computing, Vol. 34, No. 5 Volume 30, Issue 2Spring 2018Pages 217-420 Article Information Supplemental Materials Metrics Information Received:January 22, 2015Accepted:August 31, 2017Published Online:May 25, 2018 Copyright © 2018, INFORMSCite asOsman Y. Özaltın, Oleg A. Prokopyev, Andrew J. Schaefer (2018) Optimal Design of the Seasonal Influenza Vaccine with Manufacturing Autonomy. INFORMS Journal on Computing 30(2):371-387. https://doi.org/10.1287/ijoc.2017.0786 Keywordsinfluenza vaccinemultistage stochastic mixed-integer programmingbilevel programminginteger programmingPDF download
DA - 2018///
PY - 2018///
DO - 10.1287/ijoc.2017.0786
VL - 30
IS - 2
SP - 371-387
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85047815039&partnerID=MN8TOARS
KW - influenza vaccine
KW - multistage stochastic mixed-integer programming
KW - bilevel programming
KW - integer programming
ER -
TY - JOUR
TI - On a class of bilevel linear mixed-integer programs in adversarial settings
AU - Zare, M.H.
AU - Özalt?n, O.Y.
AU - Prokopyev, O.A.
T2 - Journal of Global Optimization
DA - 2018///
PY - 2018///
DO - 10.1007/s10898-017-0549-2
VL - 71
IS - 1
SP - 91-113
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85027984872&partnerID=MN8TOARS
KW - Bilevel linear mixed-integer programs
KW - Bilevel linear programs
KW - Computational complexity
KW - Strong-weak approach
KW - Pessimistic bilevel programs
ER -
TY - JOUR
TI - Quantitative modeling of user performance in multitasking environments
AU - Liu, Shijing
AU - Nam, Chang S.
T2 - Computers in Human Behavior
AB - Multitasking is one of the most important skills required for human operators to perform highly-complex and safety-critical jobs. This study proposed and validated a quantitative model for the study of user performance improvement in a multitasking environment. The Multi-Attribute Task Battery-II (MATB-II) was used in the experiments as a multitasking platform. The proposed model included quantification of stimuli from each MATB-II subtask as baud rate (bits per second), selection of task difficulty and task weight, as well as the rearrangement of task weights. This research followed a two-phase experimental approach. The first phase applied the proposed model and identified a performance baseline for each individual in a multitasking environment, MATB-II. The second phase validated the proposed model using a rearranged set of multitasks for each individual. Individual differences in working memory capacity (WMC) have been estimated as predictors of varying cognitive abilities. This study also investigated the relationship between WMC, task difficulty, and multitasking performance. Significant improvement of user performance was found after the rearrangement of tasks based on the proposed approach. This research provides a framework to quantitatively evaluate multitasking systems and improve human performance in order to understand the interaction between systems and human operators.
DA - 2018/7//
PY - 2018/7//
DO - 10.1016/J.CHB.2018.02.035
VL - 84
SP - 130-140
J2 - Computers in Human Behavior
LA - en
OP -
SN - 0747-5632
UR - http://dx.doi.org/10.1016/J.CHB.2018.02.035
DB - Crossref
KW - Multitasking
KW - Quantitative modeling
KW - MATB-II
KW - Working memory capacity
KW - Task difficulty
KW - Mental workload
ER -
TY - JOUR
TI - Cover Image
AU - Rhiu, Ilsun
AU - Bahn, Sangwoo
AU - Nam, Chang S.
AU - Yun, Myung Hwan
T2 - Human Factors and Ergonomics in Manufacturing & Service Industries
AB - The cover image, by Ilsun Rhiu et al., is based on the Research Article Affective experience of physical user interfaces: Similarities and differences among control types, DOI 10.1002/hfm.20722.
DA - 2018/2/14/
PY - 2018/2/14/
DO - 10.1002/HFM.20734
VL - 28
IS - 2
SP - i-i
J2 - Hum. Factors Man.
LA - en
OP -
SN - 1090-8471
UR - http://dx.doi.org/10.1002/HFM.20734
DB - Crossref
ER -
TY - JOUR
TI - Rapid Fabrication and Characterization of SERS Substrates
AU - Deng, Jia
AU - Dong, Jingyan
AU - Cohen, Paul
T2 - Procedia Manufacturing
AB - Surface enhanced Raman spectroscopy (SERS) is a surface-sensitive detection technique that dramatically increases the scattering signals of the analytes compared to traditional Raman spectroscopy. Rapid and low-cost fabrication of SERS substrates with easily tunable features remains a challenge, although many SERS substrates with high enhancement factors (EF) were investigated. Here, we report a novel and rapid approach of fabricating SERS substrates using ultrasonic vibration assisted nanomachining. Grids patterns with easily tuned dimensions were fabricated on PMMA surfaces. SERS substrates were fabricated after coating an 80 nm gold layer on the patterned silicon after reactive ion etching (RIE) using the patterned PMMA as the mask. Probing molecules of R6G with the area density of 2.8 × 10-12 M/mm2 can be detected, achieving an EF of 3.11 × 103. Results show a pattern with higher grids density tends to achieve a higher EF.
DA - 2018///
PY - 2018///
DO - 10.1016/J.PROMFG.2018.07.068
VL - 26
SP - 580-586
J2 - Procedia Manufacturing
LA - en
OP -
SN - 2351-9789
UR - http://dx.doi.org/10.1016/J.PROMFG.2018.07.068
DB - Crossref
KW - AFM-based nanofabrication
KW - SERS substrates
KW - ultrasonic vibration assisted nanomachining
ER -
TY - JOUR
TI - Modeling of Catalyst-free Growth Process of ZnO Nanowires
AU - Kong, Xiangcheng
AU - Wei, Chuang
AU - Zhu, Yong
AU - Cohen, Paul
AU - Dong, Jingyan
T2 - Procedia Manufacturing
AB - ZnO nanowires have been widely studied due to their unique material properties and many potential applications in electronic and optoelectronic devices. Many growth processes have been developed to synthesize ZnO nanowires. It is critically important to develop predictive process models so as to maximize the output of the nanowire synthesis. Here we report a method to characterize, quantify, and model a catalyst-free carbon-assisted ZnO nanowire growth process. Two key factors were identified for the synthesis conditions, which are reaction temperature and flow rate. Based on a factorial design method, we conducted experiments with different combinations of the two factors to study their effects on the process output (i.e. density of the nanowires), which was evaluated by a scanning electron microscope (SEM). The experimental results were analyzed using ANOVA test, and then a semi-empirical model was built to correlate the ZnO nanowire output with synthesis conditions. This model was able to describe the ZnO nanowire density with respect to synthesis conditions, which can provide a guideline for synthesis parameters selection and process optimization.
DA - 2018///
PY - 2018///
DO - 10.1016/J.PROMFG.2018.07.043
VL - 26
SP - 349-358
J2 - Procedia Manufacturing
LA - en
OP -
SN - 2351-9789
UR - http://dx.doi.org/10.1016/J.PROMFG.2018.07.043
DB - Crossref
KW - ZnO nanowire synthesis
KW - chemical vapor deposition (CVD)
KW - process modeling
ER -
TY - JOUR
TI - A survey of semiconductor supply chain models Part II: demand planning, inventory management, and capacity planning
AU - Uzsoy, Reha
AU - Fowler, John W.
AU - Mönch, Lars
T2 - International Journal of Production Research
AB - Part I of this three-part series described semiconductor supply chains from the decision-making and functional perspectives, using this as a framework to review the industrial engineering and operations research literature on the problems arising in these supply chains. Part I then reviewed the literature on Strategic Network Design, supply chain coordination, sustainability and simulation-based decision support. This paper, Part II, reviews the areas of Demand Planning, Inventory Management and Capacity Planning in semiconductor supply chains. Part III concludes the series by discussing models to support Master Planning, Production Planning and Demand Fulfilment in this industry.
DA - 2018/2/15/
PY - 2018/2/15/
DO - 10.1080/00207543.2018.1424363
VL - 56
IS - 13
SP - 4546-4564
J2 - International Journal of Production Research
LA - en
OP -
SN - 0020-7543 1366-588X
UR - http://dx.doi.org/10.1080/00207543.2018.1424363
DB - Crossref
KW - supply chain management
KW - semiconductor industry
KW - capacity planning
KW - inventory management
KW - demand uncertainty
ER -
TY - JOUR
TI - Correction to: Evaluation of Orientation Dependence of Fracture Toughness and Fatigue Crack Propagation Behavior of As-Deposited ARCAM EBM Ti-6Al-4V
AU - Seifi, Mohsen
AU - Dahar, Matthew
AU - Aman, Ron
AU - Harrysson, Ola
AU - Beuth, Jack
AU - Lewandowski, John J.
T2 - JOM
AB - There was a typographical error in Fig. 2b in the original publication of this article. It has been corrected in the image below.
DA - 2018/1/10/
PY - 2018/1/10/
DO - 10.1007/S11837-018-2736-0
VL - 70
IS - 3
SP - 436-436
J2 - JOM
LA - en
OP -
SN - 1047-4838 1543-1851
UR - http://dx.doi.org/10.1007/S11837-018-2736-0
DB - Crossref
ER -
TY - JOUR
TI - Benchmarking robustness of load forecasting models under data integrity attacks
AU - Luo, Jian
AU - Hong, Tao
AU - Fang, Shu-Cherng
T2 - International Journal of Forecasting
AB - As the internet’s footprint continues to expand, cybersecurity is becoming a major concern for both governments and the private sector. One such cybersecurity issue relates to data integrity attacks. This paper focuses on the power industry, where the forecasting processes rely heavily on the quality of the data. Data integrity attacks are expected to harm the performances of forecasting systems, which will have a major impact on both the financial bottom line of power companies and the resilience of power grids. This paper reveals the effect of data integrity attacks on the accuracy of four representative load forecasting models (multiple linear regression, support vector regression, artificial neural networks, and fuzzy interaction regression). We begin by simulating some data integrity attacks through the random injection of some multipliers that follow a normal or uniform distribution into the load series. Then, the four aforementioned load forecasting models are used to generate one-year-ahead ex post point forecasts in order to provide a comparison of their forecast errors. The results show that the support vector regression model is most robust, followed closely by the multiple linear regression model, while the fuzzy interaction regression model is the least robust of the four. Nevertheless, all four models fail to provide satisfying forecasts when the scale of the data integrity attacks becomes large. This presents a serious challenge to both load forecasters and the broader forecasting community: the generation of accurate forecasts under data integrity attacks. We construct our case study using the publicly-available data from Global Energy Forecasting Competition 2012. At the end, we also offer an overview of potential research topics for future studies.
DA - 2018/1//
PY - 2018/1//
DO - 10.1016/J.IJFORECAST.2017.08.004
VL - 34
IS - 1
SP - 89-104
J2 - International Journal of Forecasting
LA - en
OP -
SN - 0169-2070
UR - http://dx.doi.org/10.1016/J.IJFORECAST.2017.08.004
DB - Crossref
KW - Cybersecurity
KW - Data integrity attack
KW - Electric load forecasting
KW - Linear regression
KW - Neural network
KW - Support vector regression
KW - Fuzzy regression
ER -
TY - JOUR
TI - Structured linear reformulation of binary quadratically constrained quadratic programs
AU - Jiang, Shan
AU - Fang, Shu-Cherng
AU - Nie, Tiantian
AU - An, Qi
T2 - Optimization Letters
DA - 2018/11/17/
PY - 2018/11/17/
DO - 10.1007/S11590-018-1361-8
VL - 11
J2 - Optim Lett
LA - en
OP -
SN - 1862-4472 1862-4480
UR - http://dx.doi.org/10.1007/S11590-018-1361-8
DB - Crossref
KW - Quadratically constrained quadratic program
KW - Binary program
KW - Linear reformulation
KW - 0-1 mixed integer linear program
ER -
TY - JOUR
TI - A Case Study for Blockchain in Manufacturing: “FabRec”: A Prototype for Peer-to-Peer Network of Manufacturing Nodes
AU - Angrish, Atin
AU - Craver, Benjamin
AU - Hasan, Mahmud
AU - Starly, Binil
T2 - Procedia Manufacturing
AB - With product customization an emerging business opportunity, organizations must find ways to collaborate and enable sharing of information in an inherently trust-less network. In this paper, we propose – “FabRec”: a decentralized approach to handle manufacturing information generated by various organizations using blockchain technology. We propose a system in which a decentralized network of manufacturing machines and computing nodes can enable automated transparency of an organization’s capability, third party verification of such capability through a trail of past historic events and automated mechanisms to drive paperless contracts between participants using ‘smart contracts’. Our system decentralizes critical information about the manufacturer and makes it available on a peer-to-peer network composed of fiduciary nodes to ensure transparency and data provenance through a verifiable audit trail. We present a testbed platform through a combination of manufacturing machines, system-on-chip platforms and computing nodes to demonstrate mechanisms through which a consortium of disparate organizations can communicate through a decentralized network. Our prototype testbed demonstrates the value of computer code residing on a decentralized network for verification of information on the blockchain and ways in which actions can be autonomously initiated in the physical world. This paper intends to expose system elements in preparation for much larger field tests through the working prototype and discusses the future potential of blockchain for manufacturing IT.
DA - 2018///
PY - 2018///
DO - 10.1016/J.PROMFG.2018.07.154
VL - 26
SP - 1180-1192
J2 - Procedia Manufacturing
LA - en
OP -
SN - 2351-9789
UR - http://dx.doi.org/10.1016/J.PROMFG.2018.07.154
DB - Crossref
KW - blockchain
KW - cyber-physical systems
KW - smart contracts
KW - ethereum
KW - decentralized networks
KW - shareable databases
ER -
TY - JOUR
TI - Real-Time Ambulance Dispatching and Relocation
AU - Nasrollahzadeh, Amir Ali
AU - Khademi, Amin
AU - Mayorga, Maria E.
T2 - Manufacturing & Service Operations Management
AB - In this study, we develop a flexible optimization framework for real-time ambulance dispatching and relocation. In addition to ambulance redeployment, we consider a general dispatching and relocation strategy by which the decision maker has the option to (i) select any available ambulance to dispatch to a call or to queue the call and (ii) send an idle ambulance to cover the location of an ambulance just dispatched to a call. We formulate the problem as a stochastic dynamic program, and, because the state space is unbounded, an approximate dynamic programming (ADP) framework is developed to generate high-quality solutions. We assess the quality of our solutions by developing a lower bound on the expected response time and computing a lower bound on the expected fraction of late calls of any relocation policy. We test the performance of our policies and available benchmarks on an emergency medical services system in Mecklenburg County, North Carolina. The results show that our policies are near optimal and significantly outperform available benchmarks. In particular, our ADP policy reduces the expected response time and fraction of high-priority late calls by 12% and 30.6%, respectively, over the best available static benchmarks in the case study. Moreover, the results provide insights on the contribution of each dispatching, redeployment, and reallocation strategy. The online appendix is available at https://doi.org/10.1287/msom.2017.0649 .
DA - 2018/7//
PY - 2018/7//
DO - 10.1287/msom.2017.0649
VL - 20
IS - 3
SP - 467-480
J2 - M&SOM
LA - en
OP -
SN - 1523-4614 1526-5498
UR - http://dx.doi.org/10.1287/msom.2017.0649
DB - Crossref
KW - ambulance operations management
KW - dispatching
KW - redeployment
KW - reallocation
KW - approximate dynamic programming
ER -
TY - JOUR
TI - Towards Adaptive Support for Anticipatory Thinking
AU - Geden, Michael
AU - Smith, Andy
AU - Campbell, James
AU - Amos-Binks, Adam
AU - Mott, Bradford
AU - Feng, Jing
AU - Lester, James
T2 - PROCEEDINGS OF THE TECHNOLOGY, MIND, AND SOCIETY CONFERENCE (TECHMINDSOCIETY'18)
AB - Adaptive training and support technologies have been used to improve training and performance in a number of domains. However, limited work on adaptive training has examined anticipatory thinking, which is the deliberate, divergent exploration and analysis of relevant futures to avoid surprise. Anticipatory thinking engages the process of imagining how uncertainties impact the future, helps identify leading indicators and causal dependencies of future scenarios, and complements forecasting, which focuses on assessing the likelihood of outcomes. It is particularly important for intelligence analysis, mission planning, and strategic forecasting, wherein practitioners apply prospective sense-making, scenario planning, and other methodologies to identify possible options and their effects during decision making processes. However, there is currently no underlying cognitive theory supporting specific anticipatory thinking methodologies, no adaptive technologies to support their training, and no existing measures to assess their efficacy.
DA - 2018///
PY - 2018///
DO - 10.1145/3183654.3183665
SP -
KW - Anticipatory thinking
KW - cognitive process
KW - assessment
KW - training
KW - adaptive technology
ER -
TY - JOUR
TI - ASTRO-DF: A Class of Adaptive Sampling Trust-Region Algorithms for Derivative-Free Stochastic Optimization
T2 - SIAM Journal on Optimization
AB - We consider unconstrained optimization problems where only “stochastic” estimates of the objective function are observable as replicates from a Monte Carlo oracle. The Monte Carlo oracle is assumed to provide no direct observations of the function gradient. We present ASTRO-DF---a class of derivative-free trust-region algorithms, where a stochastic local model is constructed, optimized, and updated iteratively. Function estimation and model construction within ASTRO-DF is adaptive in the sense that the extent of Monte Carlo sampling is determined by continuously monitoring and balancing measures of sampling error (or variance) and structural error (or model bias) within ASTRO-DF. Such balancing of errors is designed to ensure that Monte Carlo effort within ASTRO-DF is sensitive to algorithm trajectory: sampling is higher whenever an iterate is inferred to be close to a critical point and lower when far away. We demonstrate the almost sure convergence of ASTRO-DF's iterates to first-order critical points when using stochastic polynomial interpolation models. The question of using more complicated models, e.g., regression or stochastic kriging, in combination with adaptive sampling is worth further investigation and will benefit from the methods of proof presented here. We speculate that ASTRO-DF's iterates achieve the canonical Monte Carlo convergence rate, although a proof remains elusive.
DA - 2018/1//
PY - 2018/1//
DO - 10.1137/15m1042425
UR - http://dx.doi.org/10.1137/15m1042425
KW - derivative-free optimization
KW - simulation optimization
KW - stochastic optimization
KW - trust region
ER -
TY - JOUR
TI - Multi-Stage Prediction for Zero-Inflated Hurricane Induced Power Outages
AU - Shashaani, Sara
AU - Guikema, Seth D.
AU - Zhai, Chengwei
AU - Pino, Jordan V.
AU - Quiring, Steven M.
T2 - IEEE Access
AB - Predicting hurricane power outages facilitates disaster response decision-making by electric power utilities as well as other organizations of critical importance to society. Predictive models can be built on the basis of statistical learning methods that use data from past hurricanes to capture the effects of climatological, geographical, and environmental variables on the power systems. When the dataset is largely zero-inflated, as power outage datasets often are, classical data mining methods that are based on a relatively balanced number of zeros and non-zeros may fail. General accuracy evaluation metrics also become misleading because they focus on the prevalent zero-valued responses in the dataset. We develop a new framework that operates in three stages by separating the prediction of whether or not power outages will occur from the number of customers without power. In the first stage, the zero-inflation problem is handled via a series of binary classifications. In the second stage, the severity of outages is predicted leveraging clustering techniques. In the final stage, regression models estimate the number of customers without power. We introduce a weighted accuracy metric and investigate its benefits over mean absolute error. We validate the models with data from hurricanes Dennis (2005), Ivan (2004), and Katrina (2005), and then predict power outages associated with hurricanes Matthew (2016) and Irma (2017) in the central Gulf region. The results demonstrate improvement over the traditional approaches in the context of power outage prediction.
DA - 2018///
PY - 2018///
DO - 10.1109/ACCESS.2018.2877078
VL - 6
SP - 62432-62449
UR - https://doi.org/10.1109/ACCESS.2018.2877078
KW - Power system analysis computing
KW - data analysis
KW - predictive models
KW - risk analysis
ER -
TY - JOUR
TI - Nanofinishing of FDM-fabricated components using ball end magnetorheological finishing process
AU - Kumar, Aman
AU - Alam, Zafar
AU - Khan, Dilshad Ahmad
AU - Jha, Sunil
T2 - Materials and Manufacturing Processes
AB - Fused deposition modeling (FDM) is among the extensively used and the most economical additive manufacturing processes. Currently, the surface finish obtained for FDM additive manufactured parts are not at par with the current industrial application. To overcome the limitation of high surface roughness of 3D printed parts, a novel finishing technique has been proposed which includes primary and secondary finishing processes. While facing and lapping has been used as primary finishing technique, the secondary finishing involves the use of ball end magnetorheological finishing (BEMRF) process. BEMRF process is an unconventional finishing process which utilizes an advanced approach to impart finish on magnetic as well as non-magnetic materials that may be flat or freeform in shape. This article presents the experimental and analytical study to finish a polylactic acid (PLA) workpiece material manufactured by FDM process and finished using the BEMRF technique. The surface roughness of the FDM component has been reduced from initial surface roughness Ra = 20 µm to final value of Ra = 81 nm by combined primary and secondary finishing processes. The effect of magnetorheological polishing (MRP) fluid’s composition and finishing time is discussed and is followed by optimization of MRP fluid for maximum percentage reduction in surface roughness.
DA - 2018/9/5/
PY - 2018/9/5/
DO - 10.1080/10426914.2018.1512136
VL - 34
IS - 2
SP - 232-242
J2 - Materials and Manufacturing Processes
LA - en
OP -
SN - 1042-6914 1532-2475
UR - http://dx.doi.org/10.1080/10426914.2018.1512136
DB - Crossref
KW - Magnetorheological
KW - ball
KW - end
KW - polishing
KW - fluid
KW - additive
KW - manufacturing
KW - surface
KW - roughness
ER -
TY - JOUR
TI - Poster: Towards Greater Expressiveness, Flexibility, and Uniformity in Access Control
AU - Jiang, Jiaming
AU - Chirkova, Rada
AU - Doyle, Jon
AU - Rosenthal, Arnon
T2 - SACMAT'18: PROCEEDINGS OF THE 23RD ACM SYMPOSIUM ON ACCESS CONTROL MODELS & TECHNOLOGIES
AB - Attribute-based access control (ABAC) is a general access control model that subsumes numerous earlier access control models. Its increasing popularity stems from the intuitive generic structure of granting permissions based on application and domain attributes of users, subjects, objects, and other entities in the system. Multiple formal and informal languages have been developed to express policies in terms of such attributes. The utility of ABAC policy languages is potentially undermined without a properly formalized underlying model. The high-level structure in a majority of ABAC models consists of sets of tokens and sets of sets, expressions that demand that the reader unpack multiple levels of sets and tokens to determine what things mean. The resulting reduced readability potentially endangers correct expression, reduces maintainability, and impedes validation. These problems could be magnified in models that employ nonuniform representations of actions and their governing policies. We propose to avoid these magnified problems by recasting the high-level structure of ABAC models in a logical formalism that treats all actions (by users and others) uniformly and that keeps existing policy languages in place by interpreting their attributes in terms of the restructured model. In comparison to existing ABAC models, use of a logical language for model formalization, including hierarchies of types of entities and attributes, promises improved expressiveness in specifying the relationships between and requirements on application and domain attributes. A logical modeling language also potentially improves flexibility in representing relationships as attributes to support some widely used policy languages. Consistency and intelligibility are improved by using uniform means for representing different types of controlled actions---such as regular access control actions, administrative actions, and user logins---and their governing policies. Logical languages also provide a well-defined denotational semantics supported by numerous formal inference and verification tools.
DA - 2018///
PY - 2018///
DO - 10.1145/3205977.3208950
SP - 217-219
KW - Attribute-based access control
KW - security
KW - policy formalism
KW - logical models
ER -
TY - JOUR
TI - Validation and Calibration of Freeway Reliability Methodology in the Highway Capacity Manual: Method and Case Studies
AU - Karmakar, Nabaruna
AU - Aghdashi, Seyedbehzad
AU - Rouphail, Nagui M.
AU - Williams, Billy M.
T2 - TRANSPORTATION RESEARCH RECORD
AB - Traffic congestion costs drivers an average of $1,200 a year in wasted fuel and time, with most travelers becoming less tolerant of unexpected delays. Substantial efforts have been made to account for the impact of non-recurring sources of congestion on travel time reliability. The 6 th edition of the Highway Capacity Manual (HCM) provides a structured guidance on a step-by-step analysis to estimate reliability performance measures on freeway facilities. However, practical implementation of these methods poses its own challenges. Performing these analyses requires assimilation of data scattered in different platforms, and this assimilation is complicated further by the fact that data and data platforms differ from state to state. This paper focuses on practical calibration and validation methods of the core and reliability analyses described in the HCM. The main objective is to provide HCM users with guidance on collecting data for freeway reliability analysis as well as validating the reliability performance measures predictions of the HCM methodology. A real-world case study on three routes on Interstate 40 in the Raleigh-Durham area in North Carolina is used to describe the steps required for conducting this analysis. The travel time index (TTI) distribution, reported by the HCM models, was found to match those from probe-based travel time data closely up to the 80 th percentile values. However, because of a mismatch between the actual and HCM estimated incident allocation patterns both spatially and temporally, and the fact that traffic demands in the HCM methods are by default insensitive to the occurrence of major incidents, the HCM approach tended to generate larger travel time values in the upper regions of the travel time distribution.
DA - 2018/12//
PY - 2018/12//
DO - 10.1177/0361198118798723
VL - 2672
IS - 15
SP - 93-104
SN - 2169-4052
ER -
TY - JOUR
TI - Using a deep learning network to recognise low back pain in static standing
AU - Hu, Boyi
AU - Kim, Chong
AU - Ning, Xiaopeng
AU - Xu, Xu
T2 - ERGONOMICS
AB - Low back pain (LBP) remains one of the most prevalent musculoskeletal disorders, while algorithms that able to recognise LBP patients from healthy population using balance performance data are rarely seen. In this study, human balance and body sway performance during standing trials were utilised to recognise chronic LBP populations using deep neural networks. To be specific, 44 chronic LBP and healthy individuals performed static standing tasks, while their spine kinematics and centre of pressure were recorded. A deep learning network with long short-term memory units was used for training, prediction and implementation. The performance of the model was evaluated by: (a) overall accuracy, (b) precision, (c) recall, (d) F1 measure, (e) receiver-operating characteristic and (f) area under the curve. Results indicated that deep neural networks could recognise LBP populations with precision up to 97.2% and recall up to 97.2%. Meanwhile, the results showed that the model with the C7 sensor output performed the best. Practitioner summary: Low back pain (LBP) remains the most common musculoskeletal disorder. In this study, we investigated the feasibility of applying artificial intelligent deep neural network in detecting LBP population from healthy controls with their kinematics data. Results showed a deep learning network can solve the above classification problem with both promising precision and recall performance.
DA - 2018///
PY - 2018///
DO - 10.1080/00140139.2018.1481230
VL - 61
IS - 10
SP - 1374-1381
SN - 1366-5847
KW - Low back pain
KW - motion analysis
KW - balance control
KW - deep neural network
KW - long-short-term memory
ER -
TY - CONF
TI - Simulation-based Evaluation On Integrating Additive Manufacturing Capability In A Deployed Military Environment
AU - Moore, T.A.
AU - McConnell, B.M.
AU - Wilson, J.R.
AB - This article develops a data-driven forecast of repair parts for the M109A6 Paladin self-propelled 155 mm howitzer, and this forecast drives a discrete-event simulation to assess requirements for Additive Manufacturing (AM) to be a feasible part of the U.S. Army's expeditionary supply chain. Actual part demand from the initial invasion of Iraq in 2003 during Operation Iraqi Freedom (OIF) feeds a sample-path-based forecasting method to obtain part demand for each scenario. A simulation of a conceptualized deployed Army 3D-printing facility integrated into the supply chain evaluates the performance and feasibility of the different operational policies. Results indicate current technology could support one battery (or smaller unit) for parts below 100 cubic inches while keeping performance comparable with OIF. These results are incorporated in realistic recommendations for how the Army can potentially improve its supply chain practices with this progressive technology.
C2 - 2018///
C3 - Proceedings of the 2018 Winter Simulation Conference
DA - 2018///
DO - 10.1109/wsc.2018.8632474
SP - 3721–3729
PB - IEEE
UR - http://www.lib.ncsu.edu/resolver/1840.20/36302
N1 - annote: Moore, T. A., McConnell, B. M., & Wilson, J. R. (2018). Simulation-based Evaluation On Integrating Additive Manufacturing Capability In A Deployed Military Environment. Proceedings of the 2018 Winter Simulation Conference, 3721–3729.
RN - annote: Moore, T. A., McConnell, B. M., & Wilson, J. R. (2018). Simulation-based Evaluation On Integrating Additive Manufacturing Capability In A Deployed Military Environment. Proceedings of the 2018 Winter Simulation Conference, 3721–3729.
ER -
TY - JOUR
TI - Evaluation of Goniometry and Electrogoniometry of Carpus and Elbow Joints in the Barred Owl (Strix varia)
AU - Gjeltema, Jenessa L.
AU - Degernes, Laurel A.
AU - Buckanoff, Halley D.
AU - Marcellin-Little, Denis J.
T2 - JOURNAL OF AVIAN MEDICINE AND SURGERY
DA - 2018/12//
PY - 2018/12//
DO - 10.1647/2018-267
VL - 32
IS - 4
SP - 267-278
SN - 1938-2871
KW - goniometry
KW - electrogoniometry
KW - joint angle
KW - range of motion
KW - avian
KW - barred owl
KW - Strix varia
ER -
TY - JOUR
TI - Reduced Target Facilitation and Increased Distractor Suppression During Mind Wandering
AU - Geden, Michael
AU - Staicu, Ana-Maria
AU - Feng, Jing
T2 - EXPERIMENTAL PSYCHOLOGY
AB - The perceptual decoupling hypothesis suggests a general mechanism that while mind wandering, our attention is detached from our environment, resulting in diminished processing of external stimuli. This study focused on examining two possible specific mechanisms: the global suppression of all external stimuli, and a combination of reduced target facilitation and increased distractor suppression. An attentional capture task was used in which certain trials measured distractor suppression effects and others assessed target facilitation effects. The global suppression account predicts negative impacts on both types of trials, while the combined mechanisms of reduced target facilitation and increased distractor suppression suggest that only target-present trials would be affected. Results showed no cost of mind wandering on target-absent trials, but significant distractor suppression and target facilitation effects during mind wandering on target-present trials. These findings suggest that rather than perceptual decoupling globally suppressing all stimuli, it is more selective, falling in line with evidence on strong top-down modulation.
DA - 2018/11//
PY - 2018/11//
DO - 10.1027/1618-3169/a000417
VL - 65
IS - 6
SP - 345-352
SN - 2190-5142
KW - mind wandering
KW - target facilitation
KW - distractor suppression
KW - perceptual decoupling
ER -
TY - JOUR
TI - Toward Marker-free 3D Pose Estimation in Lifting: A Deep Multi-view Solution
AU - Mehrizi, Rahil
AU - Peng, , Xi
AU - Tang, Zhiqiang
AU - Xu, Xu
AU - Metaxas, Dimitris
AU - Li, Kang
T2 - PROCEEDINGS 2018 13TH IEEE INTERNATIONAL CONFERENCE ON AUTOMATIC FACE & GESTURE RECOGNITION (FG 2018)
AB - Lifting is a common manual material handling task performed in the workplaces. It is considered as one of the main risk factors for Work-related Musculoskeletal Disorders. To improve work place safety, it is necessary to assess musculoskeletal and biomechanical risk exposures associated with these tasks, which requires very accurate 3D pose. Existing approaches mainly utilize marker-based sensors to collect 3D information. However, these methods are usually expensive to setup, timeconsuming in process, and sensitive to the surrounding environment. In this study, we propose a multi-view based deep perceptron approach to address aforementioned limitations. Our approach consists of two modules: a "view-specific perceptron" network extracts rich information independently from the image of view, which includes both 2D shape and hierarchical texture information; while a "multi-view integration" network synthesizes information from all available views to predict accurate 3D pose. To fully evaluate our approach, we carried out comprehensive experiments to compare different variants of our design. The results prove that our approach achieves comparable performance with former marker-based methods, i.e. an average error of 14:72 ± 2:96 mm on the lifting dataset. The results are also compared with state-of-the-art methods on HumanEva-I dataset [1], which demonstrates the superior performance of our approach.
DA - 2018///
PY - 2018///
DO - 10.1109/FG.2018.00078
SP - 485-491
SN - 2326-5396
KW - markerless 3D human pose estimation
KW - deep neural network
KW - lifting
ER -
TY - JOUR
TI - A comparison of mixed integer programming formulations of the capacitated lot-sizing problem
AU - Karagul, Hakan F.
AU - Warsing, Donald P.
AU - Hodgson, Thom J.
AU - Kapadia, Maaz S.
AU - Uzsoy, Reha
T2 - INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
AB - We propose a novel mixed integer programming formulation for the capacitated lot-sizing problem with set-up times and set-up carryover. We compare our formulation to two earlier formulations, the Classical and Modified formulations, and a more recent formulation due to Suerie and Stadtler. Extensive computational experiments show that our formulation consistently outperforms the Classical and Modified formulations in terms of CPU time and solution quality. It is competitive with the Suerie–Stadtler (S&S) formulation, but outperforms all other formulations on the most challenging instances, those with low-capacity slack and a dense jobs matrix. We show that some of the differences in the performance of these various formulations arise from their different use of binary variables to represent production or set-up states. We also show that the LP relaxation of our Novel formulation provides a tighter lower bound than that of the Modified formulation. Our experiments demonstrate that, while the S&S formulation provides a much tighter LP bound, the Novel formulation is better able to exploit the intelligence of the CPLEX solution engine.
DA - 2018///
PY - 2018///
DO - 10.1080/00207543.2017.1401232
VL - 56
IS - 23
SP - 7064-7084
SN - 1366-588X
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85035114913&partnerID=MN8TOARS
KW - capacitated lot sizing
KW - mixed integer linear programming
KW - set-up planning
KW - printing industry
KW - optimisation
ER -
TY - JOUR
TI - A Military Logistics Network Planning System
AU - Rogers, Matthew B.
AU - McConnell, Brandon M.
AU - Hodgson, Thom J.
AU - Kay, Michael G.
AU - King, Russell E.
AU - Parlier, Greg
AU - Thoney Barletta, Kristen
T2 - Military Operations Research
DA - 2018///
PY - 2018///
DO - 10.5711/1082598323405
VL - 23
IS - 4
SP - 5-24
UR - http://www.lib.ncsu.edu/resolver/1840.20/36268
ER -
TY - JOUR
TI - Improved osseointegration with as-built electron beam melted textured implants and improved peri-implant bone volume with whole body vibration
AU - Ruppert, David S.
AU - Harrysson, Ola L. A.
AU - Marcellin-Little, Denis J.
AU - Dahners, Laurence E.
AU - Weinhold, Paul S.
T2 - MEDICAL ENGINEERING & PHYSICS
AB - Transcutaneous osseointegrated prostheses provide stable connections to the skeleton while eliminating skin lesions experienced with socket prosthetics. Additive manufacturing can create custom textured implants capable of interfacing with amputees' residual bones. Our objective was to compare osseointegration of textured surface implants made by electron beam melting (EBM), an additive manufacturing process, to machine threaded implants. Whole body vibration was investigated to accelerate osseointegration. Two cohorts of Sprague-Dawley rats received bilateral, titanium implants (EBM vs. threaded) in their tibiae. One cohort comprising five groups vibrated at 45 Hz: 0.0 (control), 0.15, 0.3, 0.6 or 1.2 g was followed for six weeks. Osseointegration was evaluated through torsional testing and bone volume fraction (BV/TV). A second cohort, divided into two groups (control and 0.6 g), was followed for 24 days and evaluated for resonant frequency, bone-implant contact (BIC) and fluorochrome labeling. The EBM textured implants exhibited significantly improved mechanical stability independent of vibration, highlighting the benefits of using EBM to produce custom textured surfaces. Bone formation on and around the EBM textured implants increased compared to machined implants, as seen by BIC and fluorescence. No difference in torque, BIC or fluorescence among vibration levels was detected. BV/TV significantly increased at 0.6 g compared to control for both implant types.
DA - 2018/8//
PY - 2018/8//
DO - 10.1016/j.medengphy.2018.05.003
VL - 58
SP - 64-71
SN - 1873-4030
KW - Additive manufactured implants
KW - Textured implant
KW - Electron beam melting
KW - Bone-implant interface
KW - Osseointegration of Transcutaneous
KW - Prostheses
KW - Whole Body Vibration
ER -
TY - JOUR
TI - Electrohydrodynamic Printing for Advanced Micro/Nanomanufacturing: Current Progresses, Opportunities, and Challenges
AU - Han, Yiwei
AU - Dong, Jingyan
T2 - JOURNAL OF MICRO AND NANO-MANUFACTURING
AB - The paper provides an overview of high-resolution electrohydrodynamic (EHD) printing processes for general applications in high-precision micro/nanoscale fabrication and manufacturing. Compared with other printing approaches, EHD printing offers many unique advantages and opportunities in the printing resolution, tunable printing modes, and wide material applicability, which has been successfully applied in numerous applications that include additive manufacturing, printed electronics, biomedical sensors and devices, and optical and photonic devices. In this review, the EHDs-based printing mechanism and the resulting printing modes are described, from which various EHD printing processes were developed. The material applicability and ink printability are discussed to establish the critical factors of the printable inks in EHD printing. A number of EHD printing processes and printing systems that are suitable for micro/nanomanufacturing applications are described in this paper. The recent progresses, opportunities, and challenges of EHD printing are reviewed for a range of potential application areas.
DA - 2018/12//
PY - 2018/12//
DO - 10.1115/1.4041934
VL - 6
IS - 4
SP -
SN - 2166-0476
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85057826433&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Student evaluations of teaching: the impact of faculty procedures on response rates
AU - Young, Karen
AU - Joines, Jeffrey
AU - Standish, Trey
AU - Gallagher, Victoria
T2 - Assessment & Evaluation in Higher Education
AB - In the last 10–15 years, many institutions of higher education have switched from paper-and-pencil methods to online methods of administering student evaluations of teaching (SETs). One consequence has been a significant reduction in the response rates to such instruments. The current study was conducted to identify whether offering in-class time to students to complete online SETs would increase response rates. A quasi-experiment (nonequivalent group design) was conducted in which one group of tenured faculty instructed students to bring electronic devices with internet capabilities on a specified day and offered in-class time to students to complete online SETs. A communication protocol for faculty members’ use was developed and implemented. A comparison group of tenured faculty who did not offer in-class time for SET completion was identified and the difference-in-differences method was used to compare the previous year’s response rates for the same instructor teaching the same course across the two groups. Response rates were substantially higher when faculty provided in-class time to students to complete SETs. These results indicate that high response rates can be obtained for online SETs submitted by students in face-to-face classes if faculty communicate the importance of SETs in both their words and actions.
DA - 2018/4//
PY - 2018/4//
DO - 10.1080/02602938.2018.1467878
VL - 4
SP - 1-13
KW - Response rates
KW - course evaluation
KW - teacher influence
KW - higher education
ER -
TY - JOUR
TI - Logistics of carpet recycling in the U.S.: designing the collection network
AU - Sas, Iurii
AU - Joines, Jeffrey A.
AU - Thoney, Kristin A.
AU - King, Russell E.
T2 - The Journal of The Textile Institute
AB - Efficient collection of post-consumer carpet is an important part of the carpet recycling process that helps to reduce the cost of recycled materials as well as provide sufficient volumes of carpet for recycling facilities. This paper focuses on the design of a collection network for carpet in the U.S. The location set covering optimization model formulated in the paper allows locating the minimum number of collection centers throughout the U.S. to reach a specific level of population coverage and as a result, a target collection rate. To solve real-scale instances of the problem, a novel randomized greedy heuristic is developed. The heuristic is shown to perform better than existing greedy heuristics in the literature. In addition, the paper presents the resulting nationwide carpet collection networks for different levels of population coverage. The results of the study can be used for U.S. carpet recycling policy-making decisions.
DA - 2018/6/4/
PY - 2018/6/4/
DO - 10.1080/00405000.2018.1480101
VL - 6
SP - 1-10
KW - Logistics
KW - reverse logistics
KW - carpet
KW - post-consumer collection
KW - set covering problem
ER -
TY - JOUR
TI - Improving SET Response Rates: Synchronous Online Administration as a Tool to Improve Evaluation Quality
AU - Standish, Trey
AU - Joines, Jeff A.
AU - Young, Karen R.
AU - Gallagher, Victoria J.
T2 - Research in Higher Education
DA - 2018/1/11/
PY - 2018/1/11/
DO - 10.1007/s11162-017-9488-5
VL - 59
IS - 6
SP - 812-823
KW - Student evaluation of teaching
KW - SET
KW - Leverage salience theory
KW - Survey
KW - Response rate
ER -
TY - JOUR
TI - A Comparison of Virtual Reality-Based Psychomotor Task Training with Visual and Haptic Aiding
AU - Ma, Wenqi
AU - Kaber, David
AU - Gil, Guk-Ho
AU - Clamann, Michael
AU - Jeon, Wooram
AU - Zhu, Biwen
AU - Currie, Nancy
T2 - ADVANCES IN HUMAN FACTORS IN TRAINING, EDUCATION, AND LEARNING SCIENCES, AHFE 2017
AB - The objective of this research was to compare learning effects of motor and cognitive skill training with three types of virtual reality (VR) simulation. The VR simulations included haptic (guidance forces), visual (attentional cues) and a combination of haptic and visual assistance designed to accelerate training. The results of the experiment revealed that conditions providing haptic assistance (alone and in combination with visual aids) provided more cognitive skill training than the visual-only aiding condition. Similarly, the visual condition resulted in better training of fine motor skill than the haptic condition. The combination condition led to some of the smallest training effects. The present investigation incorporating healthy participants was designed as part of an ongoing research effort to provide insight for the design of VR simulations to support rehabilitation of motor skills among disabled populations or training of new skills for occupational tasks.
DA - 2018///
PY - 2018///
DO - 10.1007/978-3-319-60018-5_26
VL - 596
SP - 265-277
SN - 2194-5365
KW - Haptic simulation
KW - Virtual reality
KW - Neuropsychological tests
KW - Motor skill training
KW - Learning
ER -
TY - JOUR
TI - Not all organ dysfunctions are created equal - Prevalence and mortality in sepsis
AU - Capan, Muge
AU - Hoover, Stephen
AU - Ivy, Julie S.
AU - Miller, Kristen E.
AU - Arnold, Ryan
T2 - JOURNAL OF CRITICAL CARE
AB - While organ dysfunctions within sepsis have been widely studied, interaction between measures of organ dysfunction remains an understudied area. The objective of this study is to quantify the impact of organ dysfunction on in-hospital mortality in infected population.Descriptive and multivariate analyses of retrospective data including patients (age ≥ 18 years) hospitalized at the study hospital from July 2013 to April 2016 who met the criteria for an infection visit (62,057 unique visits).The multivariate logistic regression model had an area under the curve of 0.9. Highest odds ratio (OR) associated with increased mortality risk was identified as fraction of inspired oxygen (FiO2) > 21% (OR = 5.8 and 95% Confidence Interval (CI) 1.8-35.6), and elevated lactate >2.0 mmol/L (OR = 2.45 (95% CI = 2.1-2.8)). Most commonly observed measures of organ dysfunction within mortality visits included elevated lactate (> 2.0 mmol/L), mechanical ventilation, and oxygen saturation (SpO2)/FiO2 ratio (< 421) at least once within 48 h prior to or 24 h after anti-infective administration.There exist differences in measures of organ dysfunction occurrence and their association with mortality. These findings support increased clinical efforts to identify sepsis patients to inform diagnostic decisions.
DA - 2018/12//
PY - 2018/12//
DO - 10.1016/j.jcrc.2018.08.021
VL - 48
SP - 257-262
SN - 1557-8615
KW - Sepsis
KW - Organ dysfunction
KW - Electronic Health Records
KW - Healthcare systems
ER -
TY - JOUR
TI - Value of inventory information in allocating a limited supply of influenza vaccine during a pandemic
AU - Li, Zihao
AU - Swann, Julie L.
AU - Keskinocak, Pinar
T2 - PLOS ONE
AB - To understand the value of information on vaccine inventory levels during an influenza pandemic, we propose a simulation study to compare vaccine allocation strategies using: (i) only population information (pro-rata, or population-based, PB), (ii) both population and vaccine inventory information (population and inventory-based, PIB).We adapt an agent-based simulation model to predict the spread of the disease both geographically and temporally. We study PB and PIB when uptake rates vary geographically. The simulation study is done from 2015 to 2017, using population and commuting data from the state of Georgia from the United States census.Compared to PB under reasonable scenarios, PIB reduces the infection attack rate from 23.4% to 22.4%, decreases the amount of leftover inventory from 827 to 152 thousand, and maintains or increases the percentage of vaccinated population.Our results indicate the need for greater vaccine inventory visibility in public health supply chains, especially when supply is limited, and uptake rates vary geographically. Such visibility has a potential to decrease the number of infections, help identify locations with low uptake rates and to motivate public awareness efforts.
DA - 2018/10/25/
PY - 2018/10/25/
DO - 10.1371/journal.pone.0206293
VL - 13
IS - 10
SP -
SN - 1932-6203
ER -
TY - JOUR
TI - Driving Performance, Adaptation, and Cognitive Workload Costs of Logo Panel Detection as Mediated by Driver Age
AU - Lau, Mei Ying
AU - Kaber, David
T2 - ADVANCES IN HUMAN ASPECTS OF TRANSPORTATION
AB - This study investigated the effect of on-road visual sign usage on young (≤22 years), middle-aged (23–64 years), and elderly (65+ years) driver performance, adaptive vehicle control behavior and mental workload. Eight simulated highway driving scenarios (the primary task) were presented along with an embedded secondary task of familiar business logo sign identification. Driver workload was manipulated by varying logo panel counts on service signs, including 6- and 9-panels. Results revealed comparable driving performance among the 9- and 6-logo conditions but significant differences in sign identification among age groups. Elderly drivers produced significantly lower sign identification accuracy than other age groups (at 54–57%). Both elderly and young drivers demonstrated significantly higher cognitive workload (reduced blink duration) in response to secondary task demands as compared to middle-aged drivers. The workload during sign identification led to significantly greater elderly adaptation behaviors (higher speed reductions) and performance degradations (greater lane deviations).
DA - 2018///
PY - 2018///
DO - 10.1007/978-3-319-60441-1_74
VL - 597
SP - 775-786
SN - 2194-5365
KW - Driving performance
KW - Driver age
KW - Adaptation
KW - Cognitive workload
KW - Logo signage
KW - Blink duration
KW - Driving simulator
ER -
TY - JOUR
TI - Rounding heuristics for multiple product dynamic lot-sizing in the presence of queueing behavior
AU - Kang, Yongha
AU - Albey, Erinc
AU - Uzsoy, Reha
T2 - COMPUTERS & OPERATIONS RESEARCH
AB - We present heuristics for solving a difficult nonlinear integer programming (NIP) model arising from a multi-item single machine dynamic lot-sizing problem. The heuristic obtains a local optimum for the continuous relaxation of the NIP model and rounds the resulting fractional solution to a feasible integer solution by solving a series of shortest path problems. We also implement two benchmarks: a version of the well-known Feasibility Pump heuristic and the Surrogate Method developed for stochastic discrete optimization problems. Computational experiments reveal that our shortest path based rounding procedure finds better production plans than the previously developed myopic heuristic and the benchmarks.
DA - 2018/12//
PY - 2018/12//
DO - 10.1016/j.cor.2018.07.019
VL - 100
SP - 54-65
SN - 1873-765X
UR - https://doi.org/10.1016/j.cor.2018.07.019
KW - Nonlinear integer programming
KW - Dynamic lot-sizing
KW - Production planning
KW - Queueing
KW - Rounding heuristic
KW - Feasibility pump heuristic
KW - Surrogate problem method
ER -
TY - JOUR
TI - Diabetes and the hospitalized patient: A cluster analytic framework for characterizing the role of sex, race and comorbidity from 2006 to 2011
AU - Nataraj, Nisha
AU - Ivy, Julie Simmons
AU - Payton, Fay Cobb
AU - Norman, Joseph
T2 - HEALTH CARE MANAGEMENT SCIENCE
DA - 2018/12//
PY - 2018/12//
DO - 10.1007/s10729-017-9408-4
VL - 21
IS - 4
SP - 534-553
SN - 1572-9389
KW - Diabetes
KW - Comorbidities
KW - Patient outcomes
KW - Cluster analysis
KW - Generalized linear models
ER -
TY - JOUR
TI - An Integration of Cognitive Task Analysis Results for Situation Awareness-Focused Training Program Development
AU - Kaber, David B.
AU - Green, Rebecca S.
AU - Swangnetr, Manida
T2 - ADVANCES IN HUMAN FACTORS IN ROBOTS AND UNMANNED SYSTEMS
AB - The objective of this study was to develop an approach for translation of cognitive task analysis (CTA) results to training program content for operators of high throughput screening (HTS) systems. Currently, no standardized methods exist for translating outcomes of multiple CTA methods to support training program design and promote situation awareness (SA). We combined information requirements from a goal-directed task analysis (GDTA) and system resource requirements from abstraction hierarchy (AH) models to establish content on HTS processes and to address three levels of operator SA. The two electronic forms of training were compared with on-the-job (OTJ) training. Results provided preliminary evidence that CTA-based training increased operator knowledge beyond OTJ training and increased SA-related knowledge beyond operator initial system knowledge. A set of general guidelines was developed for design of CTA-based training programs, including methods for structuring components of the training program to support SA.
DA - 2018///
PY - 2018///
DO - 10.1007/978-3-319-60384-1_16
VL - 595
SP - 161-172
SN - 2194-5365
KW - Cognitive task analysis
KW - Life science automation
KW - Training design
KW - Situation awareness
KW - Goal-directed task analysis
KW - Abstraction hierarchy models
ER -
TY - JOUR
TI - Reverse auction mechanism design for the acquisition of prototyping services in a manufacturing-as-a-service marketplace
AU - Pahwa, Deepak
AU - Starly, Binil
AU - Cohen, Paul
T2 - JOURNAL OF MANUFACTURING SYSTEMS
AB - The affordability and increased capability of additive manufacturing machines has spawned prototyping service bureaus throughout the world. This poses a challenge to designers who are looking to obtain quality 3D printed parts at best available prices within fastest turnaround times. Customers relying on a sole source for 3D printed parts may have limited options in obtaining the best deals. From a service supplier point of view, filling excess capacity will require significant marketing budgets to reach and retain customers. In this paper, we present a novel mechanism design approach for improving the accessibility of prototyping services providers by leveraging their excess capacity. In our proposed mechanism, consumers name their own price and the mechanism will find service bureaus who are willing to make the part under the stated price. The mechanism runs similar to a reverse auction where consumers bid and the platform finds a service supplier which is able to match the stated bid price. The incentive for suppliers to participate in such a platform is the opportunity to market their excess capacity to a deal conscious consumer at a lower price without cannibalizing their existing sales channels. Qualified suppliers do not directly compete with each other for any given order since they are chosen using a two stage selection process by the service platform. This algorithm ensures that every supplier has a fair chance of selling its services on the platform regardless of price. We implement the proposed mechanism design approach in a simulated service marketplace and empirically evaluate the marketplace behavior by studying the impact of various model factors such as the supplier threshold price, the size and variety of suppliers in the marketplace.
DA - 2018/7//
PY - 2018/7//
DO - 10.1016/j.jmsy.2018.05.005
VL - 48
SP - 134-143
SN - 1878-6642
KW - Distributed manufacturing
KW - Reverse auction
KW - Mechanism design
KW - Name Your Own Price (TM)
ER -
TY - JOUR
TI - Appreciation to Our Reviewers
AU - Uzsoy, Reita
T2 - IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING
AB - Each year it is the privilege and responsibility of the Editor-in-Chief to acknowledge the reviewers whose largely anonymous efforts lie at the heart of any scientific publication, and the communities of scholars and practitioners whom it serves. As such, it is worth taking a few minutes to reflect on the purpose of the peer review process, and the contributions our reviewers make. To my mind the principal purposes of peer review are to determine whether the paper merits publication, and to help authors write better papers.
DA - 2018/11//
PY - 2018/11//
DO - 10.1109/TSM.2018.2871481
VL - 31
IS - 4
SP - 405-405
SN - 1558-2345
ER -
TY - JOUR
TI - Risk Factors for Seizures Among Young Children Monitored With Continuous Electroencephalography in Intensive Care Unit: A Retrospective Study
AU - Vlachy, Jan
AU - Jo, Mingyoung
AU - Li, Qing
AU - Ayer, Turgay
AU - Keskinocak, Pinar
AU - Swann, Julie
AU - Olson, Larry
AU - Vats, Atul
T2 - FRONTIERS IN PEDIATRICS
AB - Objective: cEEG is an emerging technology for which there are no clear guidelines for patient selection or length of monitoring. The purpose of this study was to identify subgroups of pediatric patients with high incidence of seizures. Study Design: We conducted a retrospective study on 517 children monitored by cEEG in the intensive care unit (ICU) of a children's hospital. The children were stratified using an age threshold selection method. Using regression modeling, we analyzed significant risk factors for increased seizure risk in younger and older children. Using two alternative correction procedures, we also considered a relevant comparison group to mitigate selection bias and to provide a perspective for our findings. Results: We discovered an approximate risk threshold of 14 months: below this threshold, the seizure risk increases dramatically. The older children had an overall seizure rate of 18%, and previous seizures were the only significant risk factor. In contrast, the younger children had an overall seizure rate of 45%, and the seizures were significantly associated with hypoxic-ischemic encephalopathy (HIE; p = 0.007), intracranial hemorrhage (ICH; p = 0.005), and central nervous system (CNS) infection (p = 0.02). Children with HIE, ICH, or CNS infection accounted for 61% of all seizure patients diagnosed through cEEG under 14 months. Conclusions: An extremely high incidence of seizures prevails among critically ill children under 14 months, particularly those with HIE, ICH, or CNS infection.
DA - 2018/10/15/
PY - 2018/10/15/
DO - 10.3389/fped.2018.00303
VL - 6
SP -
SN - 2296-2360
KW - continuous EEG
KW - pediatric
KW - non-convulsive
KW - intensive care
KW - brain injury
ER -
TY - JOUR
TI - Fabrication of self-recoverable flexible and stretchable electronic devices
AU - Han, Yiwei
AU - Dong, Jingyan
T2 - JOURNAL OF MANUFACTURING SYSTEMS
AB - In this paper, we developed an EHD printing process for the fabrication of high-resolution self-recoverable flexible and stretchable electronics using low-melting-point metal inks. Three different metal inks were tested for their printability on four different substrates separately to demonstrate the capability of EHD printing technology. EHD printing enables low-cost direct fabrication of metallic conductors with sub-50 μm resolution, which represents a promising way to create electronic features with metallic conductivity and excellent flexibility and stretchability. When properly designed, the EHD printed electronics provided a stable resistance under hundreds of bending cycles and many stretching and releasing cycles with high tensile strain, which demonstrates their good flexibility and stretchability in electronics applications. The printed electronics was capable of self-healing under low temperature treatment to recover from failures without sacrificing its electrical properties. Moreover, a high-resolution capacitive sensor array was designed and fabricated. A Finite Element Analysis (FEA) model was developed to study the performance of the designed touch sensor. The results from FEA model agreed well with experimental results, which demonstrated the high-resolution capability of the EHD printing for the direction fabrication of flexible and stretchable devices.
DA - 2018/7//
PY - 2018/7//
DO - 10.1016/j.jmsy.2018.04.011
VL - 48
SP - 24-29
SN - 1878-6642
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85046344028&partnerID=MN8TOARS
KW - Electrohydrodynamic (EHD) printing
KW - Metal printing
KW - Printing electronics
KW - Flexible and stretchable electronics
KW - Self-recoverable
ER -
TY - JOUR
TI - Real-time ambulance redeployment approach to improve service coverage with fair and restricted workload for EMS providers
AU - Enayati, Shakiba
AU - Mayorga, Maria E.
AU - Rajagopalan, Hari K.
AU - Saydam, Cem
T2 - Omega
AB - Emergency Medical Services (EMS) managers are concerned with providing maximum possible coverage in their service area. As emergency calls arrive into the EMS system, some ambulances become unavailable. Redeployment deals with a dynamic relocation of available ambulances so as to compensate for the loss in coverage due to busy ambulances. Unsystematic redeployment can impose superfluous workload and result in unnecessary fatigue for EMS personnel. This paper develops a real-time approach to maximize coverage with minimum possible total travel time, considering accumulated workload restrictions for personnel in a shift. While in the past real-time redeployment has been hindered due to computational issues, we find a solution to this problem by combining two computationally inexpensive models into a single framework. The proposed approach requires only knowledge of the current state of the system in a real-time manner and, due to very short run time, is applicable in practice. The performance of our real-time approach is evaluated by a discrete-event simulation developed for a large real dataset and is compared with two benchmarks in the literature; an existing dynamic redeployment approach and a static policy. The results show statistically significant improvement in average coverage, while restricting accumulated workload for EMS personnel as well as providing more evenly distributed workload between ambulances in a shift.
DA - 2018/9//
PY - 2018/9//
DO - 10.1016/j.omega.2017.08.001
VL - 79
SP - 67-80
J2 - Omega
LA - en
OP -
SN - 0305-0483
UR - http://dx.doi.org/10.1016/j.omega.2017.08.001
DB - Crossref
KW - Dynamic redeployment
KW - Healthcare
KW - EMS
KW - Workload
ER -
TY - JOUR
TI - Reverse auctions with regret-anticipated bidders
AU - Qian, Xiaohu
AU - Fang, Shu-Cherng
AU - Huang, Min
AU - An, Qi
AU - Wang, Xingwei
T2 - Annals of Operations Research
DA - 2018/9//
PY - 2018/9//
DO - 10.1007/s10479-017-2475-6
VL - 268
IS - 1-2
SP - 293–313
SN - 0254-5330 1572-9338
UR - http://dx.doi.org/10.1007/s10479-017-2475-6
KW - Reverse auction
KW - Anticipated regrets
KW - Mitigation strategy
KW - Reserve price
ER -
TY - JOUR
TI - Two-factor term structure model with uncertain volatility risk
AU - Chen, Xiaowei
AU - Gao, Jinwu
T2 - SOFT COMPUTING
DA - 2018/9//
PY - 2018/9//
DO - 10.1007/s00500-017-2737-x
VL - 22
IS - 17
SP - 5835-5841
SN - 1433-7479
KW - Two-factor term structure
KW - Uncertain short interest rate
KW - Volatility risk
KW - Bond pricing
KW - Uncertain differential equation
ER -
TY - JOUR
TI - Inventory centralization with risk-averse newsvendors
AU - Zhang, Jiahua
AU - Fang, Shu-Cherng
AU - Xu, Yifan
T2 - Annals of Operations Research
DA - 2018/9//
PY - 2018/9//
DO - 10.1007/s10479-017-2578-0
VL - 268
IS - 1-2
SP - 215–237
SN - 0254-5330 1572-9338
UR - http://dx.doi.org/10.1007/s10479-017-2578-0
KW - Inventory centralization
KW - Risk-averse
KW - Risk sharing
KW - Pareto-optimality
KW - Core
ER -
TY - JOUR
TI - The Underpinnings of Workload in Unmanned Vehicle Systems
AU - Hooey, Becky L.
AU - Kaber, David B.
AU - Adams, Julie A.
AU - Fong, Terrence W.
AU - Gore, Brian F.
T2 - IEEE TRANSACTIONS ON HUMAN-MACHINE SYSTEMS
AB - This paper identifies and characterizes factors that contribute to operator workload in unmanned vehicle systems. Our objective is to provide a basis for developing models of workload for use in design and operation of complex human-machine systems. In 1986, Hart developed a foundational conceptual model of workload, which formed the basis for arguably the most widely used workload measurement technique-the NASA Task Load Index. Since that time, however, there have been many advances in models and factor identification as well as workload control measures. Additionally, there is a need to further inventory and describe factors that contribute to human workload in light of technological advances, including automation and autonomy. Thus, we propose a conceptual framework for the workload construct and present a taxonomy of factors that can contribute to operator workload. These factors, referred to as workload drivers, are associated with a variety of system elements including the environment, task, equipment, and operator. In addition, we discuss how workload moderators, such as automation and interface design, can be manipulated in order to influence operator workload. We contend that workload drivers, workload moderators, and the interactions among drivers and moderators all need to be accounted for when building complex human-machine systems.
DA - 2018/10//
PY - 2018/10//
DO - 10.1109/THMS.2017.2759758
VL - 48
IS - 5
SP - 452-467
SN - 2168-2305
KW - Automation
KW - cognitive models
KW - remotely operated vehicles (ROVs)
KW - unmanned aerial vehicles (UAVs)
KW - unmanned ground vehicles (UGVs)
KW - unmanned underwater vehicles (UUVs)
KW - workload
ER -
TY - JOUR
TI - A proximal quadratic surface support vector machine for semi-supervised binary classification
AU - Yan, Xin
AU - Bai, Yanqin
AU - Fang, Shu-Cherng
AU - Luo, Jian
T2 - Soft Computing
DA - 2018/10//
PY - 2018/10//
DO - 10.1007/s00500-017-2751-z
VL - 22
IS - 20
SP - 6905–6919
SN - 1432-7643 1433-7479
UR - http://dx.doi.org/10.1007/s00500-017-2751-z
KW - Semi-supervised classification
KW - Proximal support vector machine
KW - Kernel-free
KW - Quadratic surface
KW - Alternating direction method
ER -
TY - JOUR
TI - Exploring the Value of Waiting During Labor
AU - Hicklin, Karen
AU - Ivy, Julie S.
AU - Payton, Fay Cobb
AU - Viswanathan, Meera
AU - Myers, Evan
T2 - SERVICE SCIENCE
AB - Of the nearly four million births that occur each year in the United States, almost one in three is a cesarean delivery. Despite the increasing C-section rate over the years, there is no evidence that the increase has caused a decrease in neonatal or maternal mortality or morbidity. Bayesian decision analysis is used to model the decision between classifying a patient as “failure-to-progress,” which is cause for a C-section, using current information (prior probability) or information gathered (posterior probability) as labor continues. The Bayesian decision models determine the conditions under which it is appropriate to gather additional information (i.e., take an observation) before deciding to end labor and perform a C-section based on the decision maker’s belief about successful labor. During an observation period, the decision maker learns more about the patient and her medical state and the likelihood of a successful vaginal delivery is updated. This study determines the conditional value of information (conditional on the decision maker’s prior belief) and determines the conditions under which information has positive value. This model can be used to facilitate shared decision making for labor and delivery through communicating beliefs, risk perceptions, and the associated actions. The online appendix is available at https://doi.org/10.1287/serv.2018.0205 .
DA - 2018/9//
PY - 2018/9//
DO - 10.1287/serv.2018.0205
VL - 10
IS - 3
SP - 334-353
SN - 2164-3970
KW - Bayesian decision analysis
KW - value of information
KW - mode of delivery
KW - health services and networks
KW - medical decision making
ER -
TY - JOUR
TI - Introduction to the Special Issue on Advancing Health Services
AU - Maillart, Lisa M.
AU - Mayorga, Maria E.
T2 - SERVICE SCIENCE
DA - 2018/9//
PY - 2018/9//
DO - 10.1287/serv.2018.0225
VL - 10
IS - 3
SP - V-VII
SN - 2164-3970
ER -
TY - JOUR
TI - Rolling horizon, multi-product production planning with chance constraints and forecast evolution for wafer fabs
AU - Ziarnetzky, Timm
AU - Moench, Lars
AU - Uzsoy, Reha
T2 - INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH
AB - In this paper, we study production planning models for semiconductor wafer fabrication facilities (wafer fabs) that consider both safety stocks at the finished goods inventory level and workload-dependent lead times. The evolution of demand forecasts over time follows the multiplicative Martingale Model of Forecast Evolution (MMFE) for multiple products and is incorporated into the planning models via shortfall-based chance constraints, permitting the simultaneous determination of production quantities and safety stocks. We study two variants of this formulation, one that considers forecast updates and one that does not. A planning model with workload-dependent lead times that does not consider safety stocks is used for comparison. The performance of the planning models is assessed in a rolling horizon environment using a simulation model of a scaled-down wafer fab. We find that the chance-constrained model with forecast updates outperforms the one without forecast updates with respect to expected service level and profit. Both chance-constrained models outperform the model without safety stocks. These results indicate that considering forecast evolution in production planning models can lead to improved performance by exploiting the advance demand information provided by the forecast updates.
DA - 2018///
PY - 2018///
DO - 10.1080/00207543.2018.1478461
VL - 56
IS - 18
SP - 6112-6134
SN - 1366-588X
KW - production planning
KW - semiconductor manufacture
KW - simulation
KW - rolling horizon
KW - forecast evolution
ER -
TY - JOUR
TI - Optimal production in a competitive market under yield uncertainty
AU - Jansen, Maria C.
AU - Ozaltin, Osman Y.
T2 - OPTIMIZATION LETTERS
DA - 2018/10//
PY - 2018/10//
DO - 10.1007/s11590-018-1288-0
VL - 12
IS - 7
SP - 1487-1502
SN - 1862-4480
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85049004706&partnerID=MN8TOARS
KW - Cournot competition
KW - Yield uncertainty
KW - Capacity constraint
KW - Influenza vaccine market
ER -
TY - JOUR
TI - Quantitative modeling of user performance in multitasking environments
AU - Liu, S. J.
AU - Nam, C. S.
AU - Fitts, E. P.
T2 - Computers in Human Behavior
DA - 2018///
PY - 2018///
VL - 84
SP - 130-140
ER -
TY - JOUR
TI - Many-server Gaussian limits for overloaded non-Markovian queues with customer abandonment
AU - Aras, A. K.
AU - Chen, X. Y.
AU - Liu, Y. A.
T2 - Queueing Systems
DA - 2018///
PY - 2018///
DO - 10.1007/s11134-018-9575-0
VL - 89
IS - 1-2
SP - 81-125
ER -
TY - JOUR
TI - Robust optimization approaches for the equitable and effective distribution of donated food
AU - Orgut, Irem Sengul
AU - Ivy, Julie S.
AU - Uzsoy, Reha
AU - Hale, Charlie
T2 - EUROPEAN JOURNAL OF OPERATIONAL RESEARCH
AB - Motivated by our eight-year partnership with a local food bank, we present two robust optimization models to support the equitable and effective distribution of donated food over the food bank's service area. Our first model addresses uncertainty in the amount of donated food counties can effectively receive and distribute, which depends on local factors such as budget and workforce that are unknown to the food bank. Assuming that the capacity of each county varies within a range, the model seeks to maximize total food distribution while enforcing a user-specified level of robustness. Our second model uses robust optimization in a nontraditional manner, treating the upper bound on the level of allowed inequity as an uncertain parameter and limiting total deviation from a perfectly equitable distribution over all counties while maximizing total food shipment. We derive structural properties of both models and develop efficient exact solution algorithms. We illustrate our models using historical data obtained from our food bank partner, summarize the policy implications of our results and examine the impact of uncertainty on outcomes and decision making.
DA - 2018/9/1/
PY - 2018/9/1/
DO - 10.1016/j.ejor.2018.02.017
VL - 269
IS - 2
SP - 516-531
SN - 1872-6860
KW - Humanitarian operations
KW - Robust optimization
KW - Uncertainty modeling
KW - Food bank
KW - Distribution
ER -
TY - JOUR
TI - On scheduling a photolithography area containing cluster tools
AU - Madathil, Sreenath Chalil
AU - Nambiar, Siddhartha
AU - Mason, Scott J.
AU - Kurz, Mary E.
T2 - COMPUTERS & INDUSTRIAL ENGINEERING
AB - Photolithography is typically the bottleneck process in semiconductor manufacturing. In this paper, we present a model for optimizing the scheduling of the photolithography process in the presence of both individual and cluster tools. The combination of these individual and cluster tools that process various layers (stages) of the semiconductor manufacturing process flow is a special type of flexible flowshop. We seek separately to minimize total weighted completion time and maximize on-time delivery performance. Experimental results suggest that our solution algorithms show promise for real world implementation as they can help to improve resource utilization, reduce job completion times, and decrease unnecessary delays in a wafer fab.
DA - 2018/7//
PY - 2018/7//
DO - 10.1016/j.cie.2018.05.036
VL - 121
SP - 177-188
SN - 1879-0550
UR - http://dx.doi.org/10.1016/j.cie.2018.05.036
KW - Photolithography
KW - Scheduling
KW - Cluster tools
KW - Optimization
KW - Heuristics
KW - Genetic algorithm
ER -
TY - JOUR
TI - Hybrid manufacturing - integrating traditional manufacturers with additive manufacturing (AM) supply chain
AU - Strong, Danielle
AU - Kay, Michael
AU - Conner, Brett
AU - Wakefield, Thomas
AU - Manogharan, Guha
T2 - ADDITIVE MANUFACTURING
AB - The ever-growing applications of Additive Manufacturing (AM) in the production of low volume- high value metal parts can be attributed to improving AM processing capabilities and complex design freedom. However, secondary post-processing using traditional processes such as machining, grinding, heat treatment and hot isostatic pressing, i.e., Hybrid Manufacturing, is required to achieve Geometric Dimensioning and Tolerancing (GD&T), surface finish and desired mechanical properties. It is often challenging for most traditional manufacturers to participate in the rapidly evolving supply chain of direct digital manufacturing (DDM) through in-house investments in cost prohibitive metal AM. This research investigates a system of strategically-located AM hubs which can integrate hybrid-AM with the capabilities and excess capacity in multiple traditional manufacturing facilities. Using North American Industry Classification System (NAICS) data for machine shops in the U.S., an uncapacitated facility location model is used to determine the optimal locations for AM hub centers based on: (1) geographical data, (2) demand and (3) cost of hybrid-AM processing. Results from this study have identified: (a) candidate US counties to build AM hubs, (b) total cost (fixed, operational and transportation) and (c) capacity utilization of the AM hubs. It was found that uncapacitated facility location models identified demand centroid as the optimal location and was affected only by AM utilization rate whereas a constrained p-median model identified 22 AM hub locations as the initial sites for AM hubs which grows to 44 AM hubs as demand increases. It was also found that transportation cost was not a significant factor in the hybrid-AM supply chain. Findings from this study will help both AM companies and traditional manufacturers to determine location in the U.S and key factors to advance the metal hybrid-AM supply chain.
DA - 2018/5//
PY - 2018/5//
DO - 10.1016/j.addma.2018.03.010
VL - 21
SP - 159-173
SN - 2214-7810
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85043586298&partnerID=MN8TOARS
KW - Hybrid manufacturing
KW - Additive manufacturing
KW - Facility location
KW - Supply chain
KW - Logistics
KW - Manufacturing hubs
KW - Direct digital manufacturing
ER -
TY - JOUR
TI - Geometric Programming with Discrete Variables Subject to Max-Product Fuzzy Relation Constraints
AU - Qin, Zejian
AU - Cao, Bingyuan
AU - Fang, Shu-Cherng
AU - Yang, Xiao-Peng
T2 - Discrete Dynamics in Nature and Society
AB - The problem of geometric programming subject to max-product fuzzy relation constraints with discrete variables is studied. The major difficulty in solving this problem comes from nonconvexity caused by these product terms in the general geometric function and the max-product relation constraints. We proposed a 0-1 mixed integer linear programming model and adopted the branch-and-bound scheme to solve the problem. Numerical experiments confirm that the proposed solution method is effective.
DA - 2018///
PY - 2018///
DO - 10.1155/2018/1610349
VL - 2018
SP - 1-8
J2 - Discrete Dynamics in Nature and Society
LA - en
OP -
SN - 1026-0226 1607-887X
UR - http://dx.doi.org/10.1155/2018/1610349
DB - Crossref
ER -
TY - JOUR
TI - Development and Characterization of Ultrasonic Vibration Assisted Nanomachining Process for Three-Dimensional Nanofabrication
AU - Deng, Jia
AU - Dong, Jingyan
AU - Cohen, Paul H.
T2 - IEEE TRANSACTIONS ON NANOTECHNOLOGY
AB - This paper develops and characterizes a three-dimensional (3-D) nanofabrication process using ultrasonic vibration assisted nanomachining based on an atomic force microscope (AFM). The superiorities of height control over force control in the process are explained and are demonstrated by the fabrication results. Three factors impacting actual feature depths are investigated, including the ultrasonic z-vibrational amplitude, the assigned base feature depth, and the machining speed. 3-D nanostructures with continuous height variations were successfully fabricated on polymethyl methacrylate (PMMA) films with the feature height manipulated through controlling the absolute height of the cantilever tip in AFM. By selecting machining parameters based on characterizations, feature dimensions can be controlled as desired values within small variances. The capability of transferring 3-D nanostructures from PMMA films to silicon substrates is further explored in this paper. After selecting recipes of the reactive ion etching process, 3-D nanostructures are successfully transferred to silicon substrates with controllable selectivity. The reported ultrasonic vibration assisted nanomachining process in height control provides a robust approach of fabricating 3-D nanostructures.
DA - 2018/5//
PY - 2018/5//
DO - 10.1109/tnano.2018.2826841
VL - 17
IS - 3
SP - 559-566
SN - 1941-0085
UR - https://doi.org/10.1109/TNANO.2018.2826841
KW - 3-D Nanomachining
KW - tip-based nanofabrication
KW - atomic force microscope (AFM)
KW - ultrasonic vibration assisted nanomachining
ER -
TY - JOUR
TI - Characterization and Modeling of Catalyst-free Carbon-Assisted Synthesis of ZnO Nanowires
AU - Kong, Xiangcheng
AU - Wei, Chuang
AU - Zhu, Yong
AU - Cohen, Paul
AU - Dong, Jingyan
T2 - JOURNAL OF MANUFACTURING PROCESSES
AB - ZnO nanowires have been widely studied due to their unique material properties and many potential applications in electronic and optoelectronic devices. Many growth processes have been developed to synthesize ZnO nanowires. It is critically important to develop predictive process models so as to maximize the output of the nanowire synthesis. Here we report a method to characterize, quantify, and model a catalyst-free carbon-assisted ZnO nanowire growth process. Two key factors were identified for the synthesis conditions, which are reaction temperature and flow rate. Based on a factorial design method, we conducted experiments with different combinations of the two factors to study their effects on the process output (i.e. density of the nanowires), which was evaluated by a scanning electron microscope (SEM). The experimental results were analyzed using ANOVA test, and then a semi-empirical model was built to correlate the ZnO nanowire output with synthesis conditions. This model was able to describe the ZnO nanowire density with respect to synthesis conditions, which can provide guideline for synthesis parameters selection and process optimization.
DA - 2018/4//
PY - 2018/4//
DO - 10.1016/j.jmapro.2018.03.018
VL - 32
SP - 438-444
SN - 1526-6125
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85044172611&partnerID=MN8TOARS
KW - ZnO nanowire synthesis
KW - chemical vapor deposition (CVD)
KW - process modeling
ER -
TY - BOOK
TI - Brain-computer interfaces handbook: Technological and theoretical advances
AU - nam,
AU - Nijholt, A.
AU - Lotte, F.
DA - 2018///
PY - 2018///
DO - 10.1201/9781351231954
PB - Boca Raton, FL: CRC Press, Taylor & Francis Group
ER -
TY - JOUR
TI - An Approach to Linguistic Multiple Attribute Decision-Making Based on Unbalanced Linguistic Generalized Heronian Mean Aggregation Operator
AU - Han, Bing
AU - Chen, Huayou
AU - Zhu, Jiaming
AU - Liu, Jinpei
T2 - COMPUTATIONAL INTELLIGENCE AND NEUROSCIENCE
AB - This paper proposes an approach to linguistic multiple attribute decision-making problems with interactive unbalanced linguistic assessment information by unbalanced linguistic generalized Heronian mean aggregation operators. First, some generalized Heronian mean aggregation operators with unbalanced linguistic information are proposed, involving the unbalanced linguistic generalized arithmetic Heronian mean operator and the unbalanced linguistic generalized geometric Heronian mean operator. For the situation that the input arguments have different degrees of importance, the unbalanced linguistic generalized weighted arithmetic Heronian mean operator and the unbalanced linguistic generalized weighted geometric Heronian mean operator are developed. Then we investigate their properties and some particular cases. Finally, the effectiveness and universality of the developed approach are illustrated by a low-carbon tourist instance and comparison analysis. A sensitivity analysis is performed as well to test the robustness of proposed methods.
DA - 2018///
PY - 2018///
DO - 10.1155/2018/1404067
VL - 2018
SP -
SN - 1687-5273
ER -
TY - JOUR
TI - Ambulance redeployment and dispatching under uncertainty with personnel workload limitations
AU - Enayati, Shakiba
AU - Ozaltin, Osman Y.
AU - Mayorga, Maria E.
AU - Saydam, Cem
T2 - IISE TRANSACTIONS
AB - Emergency Medical Services (EMS) managers are concerned with responding to emergency calls in a timely manner. Redeployment and dispatching strategies can be used to improve coverage that pertains to the proportion of calls that are responded to within a target time threshold. Dispatching refers to the choice of which ambulance to send to a call, and redeployment refers to repositioning of idle ambulances to compensate for coverage loss due to busy ambulances. Redeployment moves, however, impose additional workload on EMS personnel and must be executed with care. We propose a two-stage stochastic programming model to redeploy and dispatch ambulances to maximize the expected coverage. Our model restricts personnel workload in a shift and incorporates multiple call priority levels. We develop a Lagrangian branch-and-bound algorithm to solve realistic size instances. We evaluate the model performance based on average coverage and average ambulance workload during a shift. Our computational results indicate that the proposed Lagrangian branch-and-bound is significantly more efficient than CPLEX, especially for large problem instances. We also compare our model with benchmarks from the literature and show that it can improve the performance of an EMS system considerably, in particular with respect to mean response time to high-priority calls.
DA - 2018///
PY - 2018///
DO - 10.1080/24725854.2018.1446105
VL - 50
IS - 9
SP - 777-788
SN - 2472-5862
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85048249953&partnerID=MN8TOARS
KW - EMS
KW - workload
KW - two-stage stochastic programming
KW - decomposition algorithm
ER -
TY - JOUR
TI - Reflections on Commentaries on "Issues in Human-Automation Interaction Modeling"
AU - Kaber, David B.
T2 - JOURNAL OF COGNITIVE ENGINEERING AND DECISION MAKING
AB - This “reflections” piece identifies major themes emerging from the commentaries in the issue. I discuss how some existing issues with the levels of automation (LOAs) approach may be further resolved as well as how different perspectives can lead to richer human-automation interaction (HAI) model development. The overarching objective here is to offer some reflections and last thoughts on the overall discussion of LOA issues, but of course, there may be some concerns on which some researchers may need to “agree to disagree.” Related to this, there are a few observations in the commentaries that I respond to with points of fact. Lastly, I suggest a set of future research directions based on several methodological recommendations by commentators as well as my own perspective on what is needed in HAI modeling to move forward.
DA - 2018/3//
PY - 2018/3//
DO - 10.1177/1555343417749376
VL - 12
IS - 1
SP - 86-93
SN - 2169-5032
KW - design methods
KW - human automation interaction
KW - level of automation
KW - methods
KW - topics
ER -
TY - JOUR
TI - Label free process monitoring of 3D bioprinted engineered constructs via dielectric impedance spectroscopy
AU - Narayanan, Lokesh Karthik
AU - Thompson, Trevor L.
AU - Shirwaiker, Rohan A.
AU - Starly, Binil
T2 - BIOFABRICATION
AB - Biofabrication processes can affect biological quality attributes of encapsulated cells within constructs. Currently, assessment of the fabricated constructs is performed offline by subjecting the constructs to destructive assays that require staining and sectioning. This drawback limits the translation of biofabrication processes to industrial practice. In this work, we investigate the dielectric response of viable cells encapsulated in bioprinted 3D hydrogel constructs to an applied alternating electric field as a label-free non-destructive monitoring approach. The relationship between β-dispersion parameters (permittivity change—Δε, Cole–Cole slope factor—α, critical polarization frequency—fc) over the frequency spectrum and critical cellular quality attributes are investigated. Results show that alginate constructs containing a higher number of viable cells (human adipose derived stem cells—hASC and osteosarcoma cell line—MG63) were characterized by significantly higher Δε and α (both p < 0.05). When extended to bioprinting, results showed that changes in hASC proliferation and viability in response to changes in critical bioprinting parameters (extrusion pressure, temperature, processing time) significantly affected ∆ε, α, and fc. We also demonstrated monitoring of hASC distribution after bioprinting and changes in proliferation over time across the cross-section of a bioprinted medial knee meniscus construct. The trends in ∆ε over time were in agreement with the alamarBlue assay results for the whole construct, but this measurement approach provided a localized readout on the status of encapsulated cells. The findings of this study support the use of dielectric impedance spectroscopy as a label-free and non-destructive method to characterize the critical quality attributes of bioprinted constructs.
DA - 2018/7//
PY - 2018/7//
DO - 10.1088/1758-5090/aaccbf
VL - 10
IS - 3
SP -
SN - 1758-5090
KW - FDA PAT
KW - Process Analytical Technology
KW - bioprinting process parameters
KW - biofabrication process monitoring
KW - quality assessment
ER -
TY - JOUR
TI - Issues in Human-Automation Interaction Modeling: Presumptive Aspects of Frameworks of Types and Levels of Automation
AU - Kaber, David B.
T2 - JOURNAL OF COGNITIVE ENGINEERING AND DECISION MAKING
AB - The current cognitive engineering literature includes a broad range of models of human–automation interaction (HAI) in complex systems. Some of these models characterize types and levels of automation (LOAs) and relate different LOAs to implications for human performance, workload, and situation awareness as bases for systems design. However, some have suggested that the LOAs approach has overlooked key issues that need to be considered during the design process. Others are simply unsatisfied with the current state of the art in modeling HAI. In this paper, I argue that abandoning an existing framework with some utility for design makes little sense unless the cognitive engineering community can provide the broader design community with other sound alternatives. On this basis, I summarize issues with existing definitions of LOAs, including (a) presumptions of human behavior with automation and (b) imprecision in defining behavioral constructs for assessment of automation. I propose steps for advances in LOA frameworks. I provide evidence of the need for precision in defining behavior in use of automation as well as a need for descriptive models of human performance with LOAs. I also provide a survey of other classes of HAI models, offering insights into ways to achieve descriptive formulations of taxonomies of LOAs to support conceptual and detailed systems design. The ultimate objective of this line of research is reliable models for predicting human and system performance to serve as a basis for design.
DA - 2018/3//
PY - 2018/3//
DO - 10.1177/1555343417737203
VL - 12
IS - 1
SP - 7-24
SN - 2169-5032
KW - level of automation
KW - function allocation
KW - human-automation interaction
KW - human information processing models
KW - satisficing behavior
ER -
TY - JOUR
TI - Development of a modular computer-aided process planning (CAPP) system for additive-subtractive hybrid manufacturing of pockets, holes, and flat surfaces
AU - Basinger, Katie L.
AU - Keough, Carter B.
AU - Webster, Caroline E.
AU - Wysk, Richard A.
AU - Martin, Thomas M.
AU - Harrysson, Ola L.
T2 - INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY
DA - 2018/5//
PY - 2018/5//
DO - 10.1007/s00170-018-1674-x
VL - 96
IS - 5-8
SP - 2407-2420
SN - 1433-3015
KW - Automated process planning
KW - Subtractive machining
KW - Additive manufacturing
KW - Modular programming
KW - Automated operation planning
KW - Hybrid manufacturing process planning
ER -
TY - JOUR
TI - A new method for generating initial solutions of capacitated vehicle routing problems
AU - Karagul, K.
AU - Kay, M. G.
AU - Tokat, S.
T2 - Gazi University Journal of Science
DA - 2018///
PY - 2018///
VL - 31
IS - 2
SP - 489-513
ER -
TY - JOUR
TI - A conceptual framework of autonomous and automated agents
AU - Kaber, David B.
T2 - THEORETICAL ISSUES IN ERGONOMICS SCIENCE
AB - Recent human-automation interaction research has confused concepts of automation and autonomy and has critiqued theories of automation in human-systems in terms of aspects of autonomy. This situation has led to inappropriate expectation for design and misdirected criticism of design methods. The situation is not new and has origins in historical human factors research. I differentiate the concepts of automation and autonomy with a new framework of agents. The framework is complemented by observations on characteristics of automated vs. autonomous systems, identification of error and failure modes, and formulation of a matrix of design constraints dictating possible applications of each type of agent. Discussion is provided on levels of automation, which have also been criticized in the literature, along with coverage of types of autonomy. A definition of autonomy is mutated throughout the paper to a form with utility for engineering. In general, demands of automated agents on the human-task-environment system should be absent from design of autonomous agents and design of automated systems is always automation-centric despite best efforts at human-centred approaches. Key requirements of design for autonomy include: agent viability in a target context, agent self-governance in goal formulation and fulfilment of roles, and independence in defined tasks performance.
DA - 2018///
PY - 2018///
DO - 10.1080/1463922x.2017.1363314
VL - 19
IS - 4
SP - 406-430
SN - 1464-536X
KW - Automation
KW - autonomy
KW - levels of automation
KW - 'human-centred automation'
ER -
TY - JOUR
TI - Spiral Tool Path Generation Method on Mesh Surfaces Guided by Radial Curves
AU - Xu, Jinting
AU - Ji, Yukun
AU - Sun, Yuwen
AU - Lee, Yuan-Shin
T2 - JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME
AB - This paper presents a new spiral smoothing method to generate smooth curved tool paths directly on mesh surfaces. Spiral tool paths are preferable for computer numerical control (CNC) milling, especially for high-speed machining. At present, most spiral tool path generation methods aim mainly for pocketing, and a few methods for machining complex surface also suffer from some inherent problems, such as selection of projecting direction, preprocessing of complex offset contours, easily affected by the mesh or mesh deformation. To address the limitations, a new spiral tool path method is proposed, in which the radial curves play a key role as the guiding curves for spiral tool path generation. The radial curve is defined as one on the mesh surface that connects smoothly one point on the mesh surface and its boundary. To reduce the complexity of constructing the radial curves directly on the mesh surface, the mesh surface is first mapped onto a circular region. In this region, the radial lines, starting from the center, are planned and then mapped inversely onto the mesh surface, thereby forming the desired radial curves. By traversing these radial curves using the proposed linear interpolation method, a polyline spiral is generated, and then, the unfavorable overcuts and undercuts are identified and eliminated by supplementing additional spiral points. Spline-based technique of rounding the corners is also discussed to smooth the polyline spiral, thereby obtaining a smooth continuous spiral tool path. This method is able to not only greatly simplify the construction of radial curves and spiral tool path but also to have the ability of processing and smoothing complex surfaces. Experimental results are presented to validate the proposed method.
DA - 2018/7//
PY - 2018/7//
DO - 10.1115/1.4039918
VL - 140
IS - 7
SP -
SN - 1528-8935
KW - CNC milling
KW - mesh surface
KW - radial curves
KW - spiral tool paths
ER -
TY - JOUR
TI - Risk Perceptions of Cellphone Use While Driving: Results from a Delphi Survey
AU - Zhu, Motao
AU - Rudisill, Toni M.
AU - Rauscher, Kimberly J.
AU - Davidov, Danielle M.
AU - Feng, Jing
T2 - INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH
AB - Cellphone use while driving has been recognized as a growing and important public health issue by the World Health Organization and U.S. Center for Disease Control and Prevention. Surveys typically collect data on overall texting while driving, but do not differentiate between various forms of cellphone use. This study sought to improve the survey indicators when monitoring cellphone use among young drivers. Experts and young drivers were recruited to propose behavioral indicators (cellphone use while driving behaviors) and consequential indicators (safety consequences of cellphone use while driving) in 2016. Subsequently, experts and young drivers selected the top indicators using the Delphi survey method. We enrolled 22 experts with published articles on cellphone use while driving nationally, and seven young drivers who were freshmen at a state university. Sending a text or e-mail on a handheld phone was picked as the top behavioral indicator by both groups. However, young drivers chose playing music on a handheld phone as the second most important behavioral indicator, which was overlooked by experts. Injury/death and collision were the top two consequential indicators. Experts and young drivers identified the important survey indicators to monitor cellphone use while driving.
DA - 2018/6//
PY - 2018/6//
DO - 10.3390/ijerph15061074
VL - 15
IS - 6
SP -
SN - 1660-4601
KW - adolescents
KW - young adults
KW - distracted driving
KW - young driver
KW - surveillance
ER -
TY - JOUR
TI - Removal of Salt and Pepper Noise in Corrupted Image Based on Multilevel Weighted Graphs and IGOWA Operator
AU - Xu, Qin
AU - Zhang, Qiang
AU - Hu, Duo
AU - Liu, Jinpei
T2 - MATHEMATICAL PROBLEMS IN ENGINEERING
AB - This paper proposes a novel iterative two-stage method to suppress salt and pepper noise. In the first phase, a multilevel weighted graphs model for image representation is built to characterize the gray or color difference between the pixels and their neighbouring pixels at different scales. Then the noise detection is cast into finding the node with minimum node strength in the graphs. In the second phase, we develop a method to determine the order-inducing variables and weighted vectors of the induced generalized order weighted average (IGOWA) operator to restore the detected noise candidate. In the proposed method, the two stages are not separate, but rather alternate. Simulated experiments on gray and color images demonstrate that the proposed method can remove the noise effectively and keep the image details well in comparison to other state-of-the-art methods.
DA - 2018///
PY - 2018///
DO - 10.1155/2018/7975248
VL - 2018
SP -
SN - 1563-5147
ER -
TY - JOUR
TI - Needle geometry effect on vibration tissue cutting
AU - Barnett, Andrew C.
AU - Lee, Yuan-Shin
AU - Moore, Jason Z.
T2 - PROCEEDINGS OF THE INSTITUTION OF MECHANICAL ENGINEERS PART B-JOURNAL OF ENGINEERING MANUFACTURE
AB - Needle vibration tissue cutting is a method that has been shown to reduce tissue cutting force and thereby improve needle position accuracy inside the body. Needle accuracy is crucial for minimally invasive needle operations such as the radiation cancer treatment of brachytherapy. This article uniquely determines the importance of needle geometry in minimizing cutting force in needle vibration tissue cutting. This article also determines how vibration specifically affects cutting force. This new information was found by performing needle cutting experiments with five varying conical tipped needles being inserted into ex vivo bovine liver as well as a polyurethane sheet at varying vibratory amplitudes and frequencies. Results show that applying vibration to sharper needles greatly reduced the insertion force by up to 67%, where the blunter needles saw diminishing benefits. The tissue phantom experiments showed that vibration reduced the force needed to propagate the created crack but showed no improvement over the initial puncture force. This greater understanding of needle vibration tissue cutting can lead to improved needle geometry designs that work with vibration to reduce tissue cutting force.
DA - 2018/4//
PY - 2018/4//
DO - 10.1177/0954405416654188
VL - 232
IS - 5
SP - 827-837
SN - 2041-2975
KW - Needles
KW - tissue cutting
KW - vibration cutting
ER -
TY - JOUR
TI - Iso-Planar Feed Vector-Fields-Based Streamline Tool Path Generation for Five-Axis Compound Surface Machining With Torus-End Cutters
AU - Sun, Shuoxue
AU - Sun, Yuwen
AU - Xu, Jinting
AU - Lee, Yuan-Shin
T2 - JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME
AB - This paper presents a new vector-field-based streamline smoothing method in the parametric space and a tool orientation optimization technique for five-axis machining of complex compound surfaces with torus-end cutters. Iso-planar tool path is widely used in the machining of various types of surfaces, especially for the compound surface with multiple patches, but the operations of intersecting the compound surface with a series of planes have depended considerably on the complicated optimization methods. Instead of intersecting the surface directly with planes, a novel and effective tool path smoothing method is presented, based on the iso-planar feed vector fields, for five-axis milling of a compound surface with torus-end cutters. The iso-planar feed vector field in the parametric domain is first constructed in the form of stream function that is used to generate the candidate streamlines for tool path generation. Then, a G1 blending algorithm is proposed to blend the vector fields within the adjacent parametric domains to ensure smooth transition of cross-border streamlines. Based on the smoothened streamlines in the parametric domains, pathlines along with their correspondent side sizes are selected as desirable tool paths. Concerning a high performance machining, detailed computational techniques to determine the tool axis orientation are also presented to ensure, at each cutter contact (CC) point, the torus-end cutter touches the part surface closely without gouging. Both the computational results and machined examples are demonstrated for verification and validation of the proposed methods.
DA - 2018/7//
PY - 2018/7//
DO - 10.1115/1.4039653
VL - 140
IS - 7
SP -
SN - 1528-8935
KW - five-axis machining
KW - vector field
KW - iso-planar tool paths
KW - compound surface
KW - tool path smoothing
ER -
TY - JOUR
TI - International investing in uncertain financial market
AU - Zhang, Yi
AU - Gao, Jinwu
AU - An, Qi
T2 - SOFT COMPUTING
DA - 2018/8//
PY - 2018/8//
DO - 10.1007/s00500-018-3028-x
VL - 22
IS - 16
SP - 5335-5346
SN - 1433-7479
KW - International investing
KW - Contour process
KW - Uncertain stock model
KW - Uncertain currency model
ER -
TY - JOUR
TI - Enhanced linear reformulation for engineering optimization models with discrete and bounded continuous variables
AU - An, Qi
AU - Fang, Shu-Cherng
AU - Li, Han-Lin
AU - Nie, Tiantian
T2 - Applied Mathematical Modelling
AB - In this paper, we significantly extend the applicability of state-of-the-art ELDP (equations for linearizing discrete product terms) method by providing a new linearization to handle more complicated non-linear terms involving both of discrete and bounded continuous variables. A general class of “representable programming problems” is formally proposed for a much wider range of engineering applications. Moreover, by exploiting the logarithmic feature embedded in the discrete structure, we present an enhanced linear reformulation model which requires half an order fewer equations than the original ELDP. Computational experiments on various engineering design problems support the superior computational efficiency of the proposed linearization reformulation in solving engineering optimization problems with discrete and bounded continuous variables.
DA - 2018/6//
PY - 2018/6//
DO - 10.1016/j.apm.2017.09.047
VL - 58
SP - 140-157
J2 - Applied Mathematical Modelling
LA - en
OP -
SN - 0307-904X
UR - http://dx.doi.org/10.1016/j.apm.2017.09.047
DB - Crossref
KW - Nonlinear discrete optimization
KW - Linear reformulation
KW - Polynomial programming
KW - Signomial programming
ER -
TY - JOUR
TI - Electrohydrodynamic printing of silver nanowires for flexible and stretchable electronics
AU - Cui, Zheng
AU - Han, Yiwei
AU - Huang, Qijin
AU - Dong, Jingyan
AU - Zhu, Yong
T2 - NANOSCALE
AB - High-resolution, large-scale printing of highly conductive AgNWs for flexible and stretchable electronics using EHD printing is presented. The printed patterns show the smallest line width of 45 μm and electrical conductivity as high as ∼5.6 × 106S m−1. AgNW-based wearable heaters and ECG electrodes are fabricated.
DA - 2018/4/21/
PY - 2018/4/21/
DO - 10.1039/c7nr09570h
VL - 10
IS - 15
SP - 6806-6811
SN - 2040-3372
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85045850487&partnerID=MN8TOARS
ER -
TY - JOUR
TI - Editorial from the Incoming Editor-in-Chief
AU - Uzsoy, Reha
T2 - IEEE TRANSACTIONS ON SEMICONDUCTOR MANUFACTURING
AB - I am delighted to have the opportunity to serve as Editor-in-Chief of this prestigious transactions. I am very grateful to Prof. Anthony Muscat, the outgoing Editor-in-Chief, for bringing the opportunity to my attention and for his advice and support during the transition, as well as Jim Skowrenski of IEEE - EDS and the members of the Steering Committee who offered me the opportunity. I would also like to thank Marlene James, Rosemary Schreiber and Margaret Rafferty of IEEE Publications for their assistance as I learn the ropes. It is the collective efforts of this outstanding team that has brought the transactions to its current level.
DA - 2018/5//
PY - 2018/5//
DO - 10.1109/tsm.2018.2820239
VL - 31
IS - 2
SP - 195-195
SN - 1558-2345
UR - https://doi.org/10.1109/TSM.2018.2820239
ER -
TY - CONF
TI - Additively manufactured WR-10 copper waveguide
AU - Horn, Timothy
AU - Karakurt, I.
AU - Ledford, C.
AU - Gonzalez, M.
AU - Gamzina, D.
AU - Luhmann, N. C.
AU - Lin, L. W.
AB - Direct additive manufacturing method utilizing electron beam melting techniques was employed to produce fully dense oxygen free copper W-band waveguides. By employing smaller copper powder, finer deposition layer, and spot-melting methodology surface roughness average has been reduced from 44 μm to 28 μm. A magnetically driven abrasive process was then employed to demonstrate further surface roughness average improvement of 5 μm. Initial RF test results on as-printed WR-10 waveguide confirm that surface post-processing will be essential to implementation of additive manufacturing techniques in vacuum electronics.
C2 - 2018///
C3 - 2018 ieee international vacuum electronics conference (ivec)
DA - 2018///
DO - 10.1109/ivec.2018.8391526
SP - 409–410
ER -
TY - JOUR
TI - Additive manufacturing of an iron-based bulk metallic glass larger than the critical casting thickness
AU - Mahbooba, Zaynab
AU - Thorsson, Lena
AU - Unosson, Mattias
AU - Skoglund, Peter
AU - West, Harvey
AU - Horn, Timothy
AU - Rock, Christopher
AU - Vogli, Evelina
AU - Harrysson, Ola
T2 - APPLIED MATERIALS TODAY
AB - Fe-based bulk metallic glasses (BMG) are of increasing research interest, driven in part by a unique combination of mechanical, magnetic and chemical properties. However, the maximum thickness and geometry of BMGs achievable in traditional manufacturing processes is limited. This work examines the capabilities of laser based powder bed additive manufacturing (AM) to produce relatively large Fe-based bulk metallic glass specimens. AM fabricated specimens exceed the critical casting thickness of the material by a factor of 15 or more in all dimensions. Resulting microstructural and mechanical properties are reported. Despite decreasing quench effect with increasing build thickness, X-ray diffraction analysis suggests that a fully amorphous structure was maintained throughout the build. However, a low concentration of sparsely distributed nano-grain clusters was discovered using a high-resolution electron backscatter diffraction scan. The results pave the way for novel applications of metallic glasses achievable through appropriate material design and optimization of existing additive manufacturing processes.
DA - 2018/6//
PY - 2018/6//
DO - 10.1016/j.apmt.2018.02.011
VL - 11
SP - 264-269
SN - 2352-9407
KW - Additive manufacturing
KW - Amorphous metal
KW - Bulk metallic glass
KW - Fe
KW - Direct metal laser sintering
ER -
TY - JOUR
TI - A branch-and-cut algorithm using polar cuts for solving nonconvex quadratic programming problems
AU - Deng, Zhibin
AU - Fang, Shu-Cherng
AU - Lu, Cheng
AU - Guo, Xiaoling
T2 - Optimization
AB - In this paper, we propose a branch-and-cut algorithm for solving a nonconvex quadratically constrained quadratic programming (QCQP) problem with a nonempty bounded feasible domain. The problem is f...
DA - 2018/2//
PY - 2018/2//
DO - 10.1080/02331934.2017.1391253
VL - 67
IS - 2
SP - 359–375
SN - 0233-1934 1029-4945
UR - http://dx.doi.org/10.1080/02331934.2017.1391253
KW - Branch-and-cut algorithm
KW - nonconvex quadratically constrained quadratic programming
KW - polar cut
KW - semidefinite relaxation
ER -
TY - JOUR
TI - Models for predicting the evolution of influenza to inform vaccine strain selection
AU - Agor, Joseph K.
AU - Ozaltin, Osman Y.
T2 - HUMAN VACCINES & IMMUNOTHERAPEUTICS
AB - Influenza vaccine composition is reviewed before every flu season because influenza viruses constantly evolve through antigenic changes. To inform vaccine updates, laboratories that contribute to the World Health Organization Global Influenza Surveillance and Response System monitor the antigenic phenotypes of circulating viruses all year round. Vaccine strains are selected in anticipation of the upcoming influenza season to allow adequate time for production. A mismatch between vaccine strains and predominant strains in the flu season can significantly reduce vaccine effectiveness. Models for predicting the evolution of influenza based on the relationship of genetic mutations and antigenic characteristics of circulating viruses may inform vaccine strain selection decisions. We review the literature on state-of-the-art tools and prediction methodologies utilized in modeling the evolution of influenza to inform vaccine strain selection. We then discuss areas that are open for improvement and need further research.
DA - 2018///
PY - 2018///
DO - 10.1080/21645515.2017.1423152
VL - 14
IS - 3
SP - 678-683
SN - 2164-554X
UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-85044212421&partnerID=MN8TOARS
KW - influenza evolution
KW - prediction models
KW - influenza vaccine
KW - strain selection
KW - antigenic difference
KW - influenza
ER -
TY - JOUR
TI - Argument division based branch-and-bound algorithm for unit-modulus constrained complex quadratic programming
AU - Lu, Cheng
AU - Deng, Zhibin
AU - Zhang, Wei-Qiang
AU - Fang, Shu-Cherng
T2 - Journal of Global Optimization
DA - 2018/10//
PY - 2018/10//
DO - 10.1007/s10898-017-0551-8
VL - 70
IS - 1
SP - 171–187
SN - 0925-5001 1573-2916
UR - http://dx.doi.org/10.1007/s10898-017-0551-8
KW - Quadratic programming
KW - Semidefinite relaxation
KW - Branch-and-bound
KW - Global optimization
ER -
TY - JOUR
TI - Adaptive response criteria in road hazard detection among older drivers
AU - Feng, Jing
AU - Choi, HeeSun
AU - Craik, Fergus I. M.
AU - Levine, Brian
AU - Moreno, Sylvain
AU - Naglie, Gary
AU - Zhu, Motao
T2 - TRAFFIC INJURY PREVENTION
AB - Objectives: The majority of existing investigations on attention, aging, and driving have focused on the negative impacts of age-related declines in attention on hazard detection and driver performance. However, driving skills and behavioral compensation may accommodate for the negative effects that age-related attentional decline places on driving performance. In this study, we examined an important question that had been largely neglected in the literature linking attention, aging, and driving: can top-down factors such as behavioral compensation, specifically adaptive response criteria, accommodate the negative impacts from age-related attention declines on hazard detection during driving?Methods: In the experiment, we used the Drive Aware Task, a task combining the driving context with well-controlled laboratory procedures measuring attention. We compared younger (n = 16, age 21–30) and older (n = 21, age 65–79) drivers on their attentional processing of hazards in driving scenes, indexed by percentage of correct responses and reaction time of hazard detection, as well as sensitivity and response criteria using signal detection analysis.Results: Older drivers, in general, were less accurate and slower on the task than younger drivers. However, results from this experiment revealed that older, but not younger, drivers adapted their response criteria when the traffic condition changed in the driving scenes. When there was more traffic in the driving scene, older drivers became more liberal in their responses, meaning that they were more likely to report that a driving hazard was detected.Conclusions: Older drivers adopt compensatory strategies for hazard detection during driving. Our findings showed that, in the driving context, even at an older age our attentional functions are still adaptive according to environmental conditions. This leads to considerations on potential training methods to promote adaptive strategies that may help older drivers maintain performance in road hazard detection.
DA - 2018///
PY - 2018///
DO - 10.1080/15389588.2017.1373190
VL - 19
IS - 2
SP - 141-146
SN - 1538-957X
KW - Aging
KW - driving
KW - hazard detection
KW - attention
KW - adaptive
KW - response criterion
ER -
TY - JOUR
TI - #IHeartChemistryNCSU: free choice, content, and elements of science communication as the framework for an introductory organic chemistry project
AU - Frohock, Bram H.
AU - Winterrowd, Samantha T.
AU - Gallardo-Williams, Maria T.
T2 - CHEMISTRY EDUCATION RESEARCH AND PRACTICE
AB - Students in a large introductory organic chemistry class were given the freedom to choose an organic compound of interest and were challenged to develop an educational object (physical or digital) designed to be shared with the broader publicviasocial media. Analysis of the project results shows that most students appreciated the open nature of the assignment, and engaged in self-regulated learning by reflecting and improving on their educational object design along each step of the project. Subjects varied widely depending on the students’ personal interests, and many different educational objects were produced and shared using diverse social media outlets. As a result of this project, students reported positive outcomes including increased interest in organic chemistry and science in general as well as the acquisition of practical skills such as science communication and visual representation of science. These skills were perceived by students as being beneficial for future professional endeavors. This report describes the design and outcomes of the project, including the choice of subjects, representations, and social media channels.
DA - 2018/1/1/
PY - 2018/1/1/
DO - 10.1039/c7rp00132k
VL - 19
IS - 1
SP - 240-250
SN - 1109-4028
ER -
TY - JOUR
TI - The effect of navigation display clutter on performance and attention allocation in presentation- and simulator-based driving experiments
AU - Pankok, Carl, Jr.
AU - Kaber, David
T2 - APPLIED ERGONOMICS
AB - Display clutter can have differential effects based on environmental factors, such as workload, stress, and experiment paradigm. The objectives of the current study were to assess the effects of display clutter on driver performance and attention allocation and compare results across two experimental paradigms. Forty-two participants searched high- and low-clutter in-car navigation displays for routine information either during a static, presentation-based experiment or in a dynamic, driving simulator experiment. Results revealed display clutter to significantly alter attention allocation and degrade performance in the presentation experiment, but had little to no effect on driver performance or attention allocation in the driving simulator experiment. Results suggest that display clutter may have its greatest effect on performance and attention allocation in domains requiring extended attention to the cluttered display compared to tasks in which the cluttered display acts as a support tool for secondary tasks.
DA - 2018/5//
PY - 2018/5//
DO - 10.1016/j.apergo.2018.01.008
VL - 69
SP - 136-145
SN - 1872-9126
KW - Display clutter
KW - Driving simulator
KW - Driver performance
KW - Attention allocation
ER -
TY - JOUR
TI - Large-scale digitization of herbarium specimens: Development and usage of an automated, high-throughput conveyor system
AU - Sweeney, Patrick W.
AU - Starly, Binil
AU - Morris, Paul J.
AU - Xu, Yiming
AU - Jones, Aimee
AU - Radhakrishnan, Sridhar
AU - Grassa, Christopher J.
AU - Davis, Charles C.
T2 - TAXON
AB - Abstract The Inula complex (Asteraceae: Inulinae) is a monophyletic group which comprises eight genera distributed in Eurasia and Africa: Amblyocarpum, Carpesium, Chrysophthalmum, Inula, Pentanema, Rhanteriopsis, Telekia , and Varthemia. With the aim to shed light on the circumscription of these genera, phylogenetic analyses were performed with 293 new DNA sequences (ITS region from nrDNA and three plastid spacers from cpDNA: rps16–trnQ, rpl32–trnL, ndhF–rpl32). It is concluded that both Inula and Pentanema are paraphyletic and that generic delimitations within the Inula complex need to be revised. Based on the results of the analyses, together with morphological and karyological data, we argue that the best solution is a new circumscription of the genus Pentanema including an amended description and 24 new combinations of former Inula species. Resurrection of the names Codonocephalum, Monactinocephalus and Vicoa is proposed to preserve the monophyly of the genera included in the Inula complex. Incongruences between nrDNA and cpDNA are documented and discussed.
DA - 2018/2//
PY - 2018/2//
DO - 10.12705/671.9
VL - 67
IS - 1
SP - 165-178
SN - 1996-8175
KW - automation
KW - biodiversity informatics
KW - digitization
KW - herbarium specimens
KW - imaging
KW - New England
KW - transcription
KW - workflows
ER -
TY - JOUR
TI - Impact of posture choice on one-handed pull strength variations at low, waist, and overhead pulling heights
AU - Yu, Denny
AU - Xu, Xu
AU - Lin, Jia-Hua
T2 - INTERNATIONAL JOURNAL OF INDUSTRIAL ERGONOMICS
AB - Manual exertions with one hand are commonly performed; however, current one-handed normative strength databases note large strength variations not explained by participant demographics, e.g., age and gender. This study models how the postures that participants choose impact their one-handed pull strength. Lower-extremity posture, defined as distance from handle, were measured for 31 participants performing two maximum one-handed frontal pull exertions at three handle heights, resulting in a strength-posture dataset of 186 maximal exertions. Regression models with anthropometric and lower extremity positions were created for each handle height. Smaller distances between the front-foot and handle were associated with higher strength. Larger back-foot distance to handle was positively associated with strength for low and waist-level handle heights. Larger hip distances from the handle increased pull strengths and interacted with feet positions. This study quantifies the relationship between one-handed pull strength with anthropometry and postures and provides practitioners posture-based equations that can be used to estimate safe pull strengths given workplace posture constraints. Maximum one-handed pull strength models are presented that can assist practitioners in: 1) assessing whether strength demands are within worker's capability in the workplace, 2) designing workplaces that better accommodate the range of postures chosen during maximum exertion, and 3) identify workplace layout constraints that adversely impact strength capabilities.
DA - 2018/3//
PY - 2018/3//
DO - 10.1016/j.ergon.2017.07.004
VL - 64
SP - 226-234
SN - 1872-8219
KW - Industrial ergonomics
KW - Biomechanics
KW - Push and pull
KW - Isometric strength
KW - Postures
ER -
TY - JOUR
TI - Immersion of virtual reality for rehabilitation - Review
AU - Rose, Tyler
AU - Nam, Chang S.
AU - Chen, Karen B.
T2 - Applied Ergonomics
AB - Virtual reality (VR) shows promise in the application of healthcare and because it presents patients an immersive, often entertaining, approach to accomplish the goal of improvement in performance. Eighteen studies were reviewed to understand human performance and health outcomes after utilizing VR rehabilitation systems. We aimed to understand: (1) the influence of immersion in VR performance and health outcomes; (2) the relationship between enjoyment and potential patient adherence to VR rehabilitation routine; and (3) the influence of haptic feedback on performance in VR. Performance measures including postural stability, navigation task performance, and joint mobility showed varying relations to immersion. Limited data did not allow a solid conclusion between enjoyment and adherence, but patient enjoyment and willingness to participate were reported in care plans that incorporates VR. Finally, different haptic devices such as gloves and controllers provided both strengths and weakness in areas such movement velocity, movement accuracy, and path efficiency.
DA - 2018/5//
PY - 2018/5//
DO - 10.1016/j.apergo.2018.01.009
VL - 69
SP - 153-161
J2 - Applied Ergonomics
LA - en
OP -
SN - 0003-6870
UR - http://dx.doi.org/10.1016/j.apergo.2018.01.009
DB - Crossref
KW - Haptic feedback
KW - Rehabilitation
KW - Virtual reality
ER -
TY - JOUR
TI - Functional law of the iterated logarithm for multi-server queues with batch arrivals and customer feedback
AU - Guo, Yongjiang
AU - Liu, Yunan
AU - Pei, Renhu
T2 - ANNALS OF OPERATIONS RESEARCH
DA - 2018/5//
PY - 2018/5//
DO - 10.1007/s10479-017-2529-9
VL - 264
IS - 1-2
SP - 157-191
SN - 1572-9338
KW - Functional law of the iterated logarithm
KW - Multi-server queue
KW - Batch arrival
KW - Customer feedback
KW - Nonexponential service times
KW - Strong approximation
ER -
TY - JOUR
TI - A computer vision based method for 3D posture estimation of symmetrical lifting
AU - Mehrizi, Rahil
AU - Peng, , Xi
AU - Xu, Xu
AU - Zhang, Shaoting
AU - Metaxas, Dimitris
AU - Li, Kang
T2 - JOURNAL OF BIOMECHANICS
AB - Work-related musculoskeletal disorders (WMSD) are commonly observed among the workers involved in material handling tasks such as lifting. To improve work place safety, it is necessary to assess musculoskeletal and biomechanical risk exposures associated with these tasks. Such an assessment has been mainly conducted using surface marker-based methods, which is time consuming and tedious. During the past decade, computer vision based pose estimation techniques have gained an increasing interest and may be a viable alternative for surface marker-based human movement analysis. The aim of this study is to develop and validate a computer vision based marker-less motion capture method to assess 3D joint kinematics of lifting tasks. Twelve subjects performing three types of symmetrical lifting tasks were filmed from two views using optical cameras. The joints kinematics were calculated by the proposed computer vision based motion capture method as well as a surface marker-based motion capture method. The joint kinematics estimated from the computer vision based method were practically comparable to the joint kinematics obtained by the surface marker-based method. The mean and standard deviation of the difference between the joint angles estimated by the computer vision based method and these obtained by the surface marker-based method was 2.31 ± 4.00°. One potential application of the proposed computer vision based marker-less method is to noninvasively assess 3D joint kinematics of industrial tasks such as lifting.
DA - 2018/3/1/
PY - 2018/3/1/
DO - 10.1016/j.jbiomech.2018.01.012
VL - 69
SP - 40-46
SN - 1873-2380
KW - Computer vision
KW - Marker-less motion capture
KW - Joint kinematics assessment
KW - Lifting
KW - Discriminative approach
ER -
TY - JOUR
TI - Effect of Distraction on Hazard Recognition and Safety Risk Perception
AU - Namian, Mostafa
AU - Albert, Alex
AU - Feng, Jing
T2 - JOURNAL OF CONSTRUCTION ENGINEERING AND MANAGEMENT
AB - Both hazard recognition and safety risk perception are fundamental to effective safety management. When construction hazards remain unrecognized or the associated safety risk remains unperceived, the likelihood of human errors and injuries increases. Unfortunately, recent studies have shown that a large number of construction hazards remain unrecognized in typical workplaces. Likewise, past research has demonstrated that safety risk is widely underestimated in construction. Therefore, to improve safety performance, a proper understanding of factors that influence hazard recognition and safety risk perception is vital. Toward achieving this goal, the objective of the current study is to evaluate the effect of distractions—which are ubiquitous in construction environments—on the hazard recognition performance and safety risk perception of workers. The study goals are accomplished through an experimental effort involving 70 construction workers representing various specialty trades. The workers were randomly assigned to a distracted or undistracted condition, and their hazard recognition performance and safety risk perception levels were measured using construction case images. The study findings revealed that the distracted workers recognized a smaller proportion of hazards compared with undistracted workers. However, there were no significant differences in the level of perceived safety risk between the two groups. A closer examination of the data revealed that the safety risk perception levels for the undistracted workers are positively related to their hazard recognition performance. In other words, when undistracted workers recognize a larger proportion of hazards, they also perceive higher levels of safety risk. However, no such relationship was observed for the distracted workers, suggesting that the perceived risk was unrelated to or not dependent on their hazard recognition performance. The findings suggest that workplace distractions can adversely affect hazard recognition, safety risk perception, and safety performance. Given that constuction workers are already exposed to numerous distractors in typical workplaces, contractors seeking to introduce emerging technologies such as drones, mobile devices, and smart robots must be cognizant of their potential distracting effects. The current study represents the first empirical effort investigating the effect of workplace distraction on construction hazard recognition and safety risk perception.
DA - 2018/4//
PY - 2018/4//
DO - 10.1061/(asce)co.1943-7862.0001459
VL - 144
IS - 4
SP -
SN - 1943-7862
KW - Construction safety
KW - Hazard recognition
KW - Hazard identification
KW - Safety risk perception
KW - Distraction
KW - Injury prevention
ER -
TY - JOUR
TI - Does distance to a cystic fibrosis center impact health outcomes?
AU - Johnson, Ben
AU - Ngueyep, Rodrigue
AU - Schechter, Michael S.
AU - Serban, Nicoleta
AU - Swann, Julie
T2 - Pediatric Pulmonology
AB - Abstract Introduction This paper considers the impact of geographic distance from cystic fibrosis centers on lung function in children, young adults, and adults with cystic fibrosis. Methods Clinical patient‐level data on 20 351 patients from 1986 to 2011 were evaluated from the Cystic Fibrosis Foundation National Patient Registry. We measure distance using a patient's zip code centroid to the center where they received care. A heteroscedastic mixed effects model was used to capture the association of distance with longitudinal variation in patients’ lung function. Results Children, young adults, and adults in lower socioeconomic categories had a %FEV 1 between 3 and 10 percentage‐points lower than those living in higher income areas and those privately insured. For patients who changed distance categories, high distance was associated with lower lung function in young adults ( P ‐value <0.001). For older patients we observed the reverse, suggesting that the choice to move farther away is associated with better health ( P ‐value <0.001). For patients who did not change distance categories, only medium distance in children was significant ( P ‐value = 0.01). Known confounding factors including age and CFTR mutation class were statistically significantly associated to health outcomes ( P ‐value <0.001). Conclusions This study shows distance is not found to be associated with health lung function among patients whose distance category remained unchanged during the analysis. For patients who move, the association of health with distance depends on the age of the patient; adult patients further from their care center are healthier. Overall, we find that socioeconomic and genetic factors appear to impact health outcomes to a greater extent.
DA - 2018/1/23/
PY - 2018/1/23/
DO - 10.1002/ppul.23940
VL - 53
IS - 3
SP - 284-292
J2 - Pediatr Pulmonol
LA - en
OP -
SN - 8755-6863
UR - http://dx.doi.org/10.1002/ppul.23940
DB - Crossref
KW - cystic fibrosis
KW - health services accessibility
KW - outcome assessment
ER -
TY - JOUR
TI - Core of the Reinsurance Market with Dependent Risks
AU - Zhang, Jia-Hua
AU - Fang, Shu-Cherng
AU - Xu, Yi-Fan
T2 - Journal of the Operations Research Society of China
DA - 2018/3//
PY - 2018/3//
DO - 10.1007/s40305-017-0173-3
VL - 6
IS - 1
SP - 49–57
SN - 2194-668X 2194-6698
UR - http://dx.doi.org/10.1007/s40305-017-0173-3
KW - Core
KW - Risk premium
KW - Reinsurance market
KW - Exponential utility
KW - Cooperative game
ER -
TY - JOUR
TI - Affective experience of physical user interfaces: Similarities and differences among control types
AU - Rhiu, Ilsun
AU - Bahn, Sangwoo
AU - Nam, Chang S.
AU - Yun, Myung Hwan
T2 - HUMAN FACTORS AND ERGONOMICS IN MANUFACTURING & SERVICE INDUSTRIES
AB - Abstract This study aims to determine similarities and differences in affective experience when manipulating 3 physical user interfaces (PUIs): button, touch screen, and jog dial inputs. First, we conducted literature and expert reviews to identify key affective experiences of PUI manipulation. As a result, seven affective experiences (Softness, Elasticity, Heaviness, Smoothness, Sharpness, Clarity of Feedback, and Rattle) were identified, and they were categorized into two dimensions (Force and Feedback Vibration). Three experiments, including 51 types of buttons, 25 synthesized stimuli for touch screen, and 51 types of jog dials, were then conducted to determine the relationship between affective experiences, satisfaction, and physical parameters of each PUI. According to the results, it was common for all three PUIs that Clarity of Feedback was the most important factor for satisfaction. However, there were also differences between the effects of affective experiences and physical parameters. User satisfaction on manipulating jog dials was found to be less affected by affective experiences than buttons and touch screens. Among physical parameters, the strength of feedback was the most important factor for the affective experience of buttons and touch screens, whereas the period of feedback was the most important factor for jog dials. These similarities and differences could be explained by cognitive and manipulative factors (e.g., attention level, types of feedback, and hand posture of manipulation). The results of this study can help researchers and practitioners better understand and enhance the affective aspects of PUI manipulations.
DA - 2018/3//
PY - 2018/3//
DO - 10.1002/hfm.20722
VL - 28
IS - 2
SP - 56-68
SN - 1520-6564
KW - affective experience
KW - button
KW - jog dial
KW - PUI
KW - touch screen
ER -
TY - JOUR
TI - A Highway-Driving System Design Viewpoint Using an Agent-Based Modeling of an Affordance-Based Finite State Automata
AU - Ransikarbum, Kasin
AU - Kim, Namhun
AU - Ha, Sangho
AU - Wysk, Richard A.
AU - Rothrock, Ling
T2 - IEEE ACCESS
AB - This paper presents an agent-based modeling framework for affordance-based driving behaviors during the exit maneuver of driver agents in human-integrated transportation problems. We start our discussion from one novel modeling framework based on the concept of affordance called the affordancebased finite state automata (AFSA) model, which incorporates the human perception of resource availability and action capability. Then, the agent-based simulation illustrates the validity of the AFSA framework for the highway-lane-driver system. Next, the comparative study between real driving data and agent-based simulation outputs is provided using the transition diagram. Finally, we perform a statistical analysis and a correlation study to analyze affordance-based driving behavior of driver agents. The simulation results show that the AFSA model well represents the perception-based human actions and drivers' characteristics, which are essential for the design viewpoint of control framework of human driver modeling. This paper is also expected to benefit a designed control for autonomous/self-driving car in the future.
DA - 2018///
PY - 2018///
DO - 10.1109/access.2017.2782257
VL - 6
SP -
SN - 2169-3536
KW - Agent-based modeling
KW - affordance
KW - finite state automata
KW - driving behavior
KW - human-machine interactions
ER -
TY - JOUR
TI - Staffing to Stabilize the Tail Probability of Delay in Service Systems with Time-Varying Demand
AU - Liu, Yunan
T2 - OPERATIONS RESEARCH
AB - Analytic formulas are developed to set the time-dependent number of servers to stabilize the tail probability of customer waiting times for the G t /GI/s t + GI queueing model, which has a nonstationary non-Poisson arrival process (the G t ), nonexponential service times (the first GI), and allows customer abandonment according to a nonexponential patience distribution (the +GI). Specifically, for any delay target w > 0 and probability target α ∈ (0, 1), we determine appropriate staffing levels (the s t ) so that the time-varying probability that the waiting time exceeds a maximum acceptable value w is stabilized at α at all times. In addition, effective approximating formulas are provided for other important performance functions such as the probabilities of delay and abandonment, and the means of delay and queue length. Many-server heavy-traffic limit theorems in the efficiency-driven regime are developed to show that (i) the proposed staffing function achieves the goal asymptotically as the scale increases, and (ii) the proposed approximating formulas for other performance measures are asymptotically accurate as the scale increases. Extensive simulations show that both the staffing functions and the performance approximations are effective, even for smaller systems having an average of three servers. The e-companion is available at https://doi.org/10.1287/opre.2017.1678 .
DA - 2018///
PY - 2018///
DO - 10.1287/opre.2017.1678
VL - 66
IS - 2
SP - 514-534
SN - 0030-364X
KW - staffing algorithms
KW - service systems
KW - capacity planning
KW - many-server queues
KW - efficiency-driven
KW - time-varying arrivals
KW - queues with abandonment
KW - nonstationary queues
KW - nonexponential distributions
ER -
TY - JOUR
TI - Effect of police mobile computer terminal interface design on officer driving distraction
AU - Zahabi, Maryam
AU - Kaber, David
T2 - APPLIED ERGONOMICS
AB - Several crash reports have identified in-vehicle distraction to be a primary cause of emergency vehicle crashes especially in law enforcement. Furthermore, studies have found that mobile computer terminals (MCTs) are the most frequently used in-vehicle technology for police officers. Twenty police officers participated in a driving simulator-based assessment of visual behavior, performance, workload and situation awareness with current and enhanced MCT interface designs. In general, results revealed MCT use while driving to decrease officer visual attention to the roadway, but usability improvements can reduce the level of visual distraction and secondary-task completion time. Results also suggest that use of MCTs while driving significantly reduces perceived level of driving environment awareness for police officers and increases cognitive workload. These findings may be useful for MCT manufacturers in improving interface designs to increase police officer and civilian safety.
DA - 2018/2//
PY - 2018/2//
DO - 10.1016/j.apergo.2017.09.006
VL - 67
SP - 26-38
SN - 1872-9126
KW - Mobile computer terminal
KW - Driver performance
KW - Attention allocation
KW - Workload
KW - Situation awareness
ER -
TY - JOUR
TI - A survey of risk factors for digit injuries among dogs training and competing in agility events
AU - Sellon, D. C.
AU - Martucci, K.
AU - Wenz, J. R.
AU - Marcellin-Little, D. J.
AU - Powers, M.
AU - Cullen, K. L.
T2 - Journal of the American Veterinary Medical Association
AB - OBJECTIVE To identify potential risk factors for digit injuries in dogs training and competing in agility events. DESIGN Internet-based, retrospective, cross-sectional survey. ANIMALS 1,081 dogs training or competing in agility events. PROCEDURES Data were collected for eligible animals via retrospective surveys distributed electronically to handlers of dogs participating in agility-related activities. Variables evaluated included demographic (handlers) and signalment (dogs) information, physical characteristics of dogs, and injury characteristics. A separate survey of dogs competing in similar agility-related activities but without digit injuries was also administered. Multivariable logistic regression was used to develop a model for assessment of risk factors. RESULTS Data were collected from 207 agility dogs with digit injuries and 874 agility dogs without digit injuries. Factors associated with significantly increased odds of injury included Border Collie breed (OR, 2.3; 95% confidence interval [CI], 1.5 to 3.3), long nails (OR, 2.4; 95% CI, 1.3 to 4.5), absence of front dewclaws (OR, 1.9; 95% CI, 1.3 to 2.6), and greater weight-to-height ratio (OR, 1.5; 95% CI, 1.1 to 2.0). Odds of injury decreased with increasing age of the dog (OR, 0.8; 95% CI, 0.76 to 0.86). CONCLUSIONS AND CLINICAL RELEVANCE Results should be cautiously interpreted because of potential respondent and recall bias and lack of review of medical records. Nevertheless, results suggested that retaining healthy dewclaws, maintaining lean body mass, and trimming nails short for training and competition may decrease the likelihood of digit injuries. Research to investigate training practices, obstacle construction specifcations, and surface considerations for dogs competing in agility activities is indicated.
DA - 2018///
PY - 2018///
DO - 10.2460/javma.252.1.75
VL - 252
IS - 1
SP - 75-83
ER -
TY - JOUR
TI - PLSP based layered contour generation from point cloud for additive manufacturing
AU - Xu, Jinting
AU - Hou, Wenbin
AU - Sun, Yuwen
AU - Lee, Yuan-Shin
T2 - ROBOTICS AND COMPUTER-INTEGRATED MANUFACTURING
AB - This paper presents a new Planar Least-Squares Projection (PLSP) method to accurately construct the layered contours directly from the point cloud for additive manufacturing. With the rapid development of 3D measuring technology, the dense and accurate point cloud, which can represent more accurate geometry information of a physical object than before, has been readily available. Additive manufacturing based directly on such point cloud is considered to be a promising alternative for fabricating the complex parts, but it requires the research on effective processing methods of the point set surface. In this paper, the presented PLSP method addresses this technical challenge for additive manufacturing. Mathematical modeling and processing of point cloud are presented to identify projections and construct accurate layered contours by considering both the least-square projection errors and projection distance selection criteria from measured point cloud. Technique of assigning new set of weights on measure scattered point cloud is discussed to achieve accurate layered contour development. The presented PLSP method with the new weight function and the consideration of point cloud deviation distances in sliced contour development is able to avoid the occurrence of the wrong projection that many other current methods suffer from. Technique of integrating the presented PLSP with the boundary point sequence curve (PSC) method is also discussed in this paper to eliminate contour development errors by considering the similarity in shape and closeness in distance for the ideal layered contours. Since this presented method does not involve the non- linear optimization, it is mathematically robust, and it can ensure the constructed layered contours lie accurately on the underlying nominal surface, and also has the ability of recognizing and processing the multi-contours on a common slicing plane. Both computational and experimental results based on the presented method are presented for validation.
DA - 2018/2//
PY - 2018/2//
DO - 10.1016/j.rcim.2017.05.006
VL - 49
SP - 1-12
SN - 1879-2537
KW - Additive manufacturing
KW - Layered contour
KW - Slicing of point cloud
KW - Planar Least-Squares Projection
KW - Point sequence curve
ER -
TY - JOUR
TI - New technologies in human factors and ergonomics research and practice
AU - Lin, Jia-Hua
AU - Kirlik, Alex
AU - Xu, Xu
T2 - APPLIED ERGONOMICS
DA - 2018/1//
PY - 2018/1//
DO - 10.1016/j.apergo.2017.08.012
VL - 66
SP - 179-181
SN - 1872-9126
ER -
TY - JOUR
TI - Identification of task demands and usability issues in police use of mobile computing terminals
AU - Zahabi, Maryam
AU - Kaber, David
T2 - APPLIED ERGONOMICS
AB - Crash reports from various states in the U.S. have shown high numbers of emergency vehicle crashes, especially in law enforcement situations. This study identified the perceived importance and frequency of police mobile computing terminal (MCT) tasks, quantified the demands of different tasks using a cognitive performance modeling methodology, identified usability violations of current MCT interface designs, and formulated design recommendations for an enhanced interface. Results revealed that “access call notes”, “plate number check” and “find location on map” are the most important and frequently performed tasks for officers. “Reading plate information” was also found to be the most visually and cognitively demanding task-method. Usability principles of “using simple and natural dialog” and “minimizing user memory load” were violated by the current MCT interface design. The enhanced design showed potential for reducing cognitive demands and task completion time. Findings should be further validated using a driving simulation study.
DA - 2018/1//
PY - 2018/1//
DO - 10.1016/j.apergo.2017.08.013
VL - 66
SP - 161-171
SN - 1872-9126
KW - Mobile computer terminal
KW - Decision tree analysis
KW - Cognitive modeling
KW - Interface design
KW - Driver distraction
ER -
TY - JOUR
TI - Identification of heel strike under a slippery condition
AU - Chang, Wen-Ruey
AU - Xu, Xu
T2 - APPLIED ERGONOMICS
AB - Kinematics at heel strike instant (HSI) has been used to quantify slip severity. However, methods to identify HSI remain ambiguous and have not been evaluated under slippery conditions. A glass force plate was used to observe the contact interface between shoe and floor under slippery conditions. HSIs identified from the video captured beneath the force plate and from the force plate and kinematics were compared. The results showed that HSIs identified with the video were closer to those identified with the normal force threshold (NFT) (9.0 ms ± 5.5 ms) than were most of those identified with kinematics. Slips with a longer distance travelled between NFT HSI and video HSI had a larger heel horizontal velocity (>0.8 m/s) and a smaller foot angular velocity (<100deg/s) at the NFT instant, and were still part of the forward swing. The results show that improved methods are needed over NFT to identify HSI, especially under slippery conditions.
DA - 2018/1//
PY - 2018/1//
DO - 10.1016/j.apergo.2017.08.004
VL - 66
SP - 32-40
SN - 1872-9126
KW - Heel contact
KW - High speed camera
KW - Kinematics
KW - Force plate
ER -