@article{hauser_king_wysk_harrysson_2021, title={Resource planning for direct fabrication of customized orthopedic implants using EBM technology}, volume={60}, ISSN={["1878-6642"]}, url={https://doi.org/10.1016/j.jmsy.2021.07.003}, DOI={10.1016/j.jmsy.2021.07.003}, abstractNote={Medical innovations and patient expectations are pushing healthcare toward personalized medicine. In orthopedics, the concept of patient-specific implants could be economically realized with the use of additive manufacturing. Knee and hip replacements are some of the most common musculoskeletal procedures performed in the United States. Joint replacement implants are typically offered in standard sizes and geometries. The mass customization of theses prostheses, however, can improve patient outcomes and reduce medical costs. Mass customization is not economically feasible with traditional manufacturing methods because of the high fixed tooling costs for each geometry. The freedom of design offered by additive manufacturing presents a viable production alternative for unique personal geometry. The objective of this paper is to develop two new analytic models that can be used to investigate a complex additive manufacturing supply chain. The focus of the model is to provide planning tools and a methodology for the direct production of customized orthopedic implants using electron beam melting, an additive manufacturing technology. First, a production model for an additive manufacturing-based system is created. Next, resource planning for a single customized implant system is performed using a simulation model. A queuing model is developed for rapid systems analysis. The staffing requirement predictions of the two models align closely for production of a singular, customized implant. A detailed systems analysis of an additive manufacturing supply chain is conducted to illustrate the use of these models. The queueing model is analytically tractable, so it is extended to describe the production of standard and customized versions of multiple implant families.}, journal={JOURNAL OF MANUFACTURING SYSTEMS}, publisher={Elsevier BV}, author={Hauser, Margaret and King, Russell and Wysk, Richard and Harrysson, Ola}, year={2021}, month={Jul}, pages={500–511} }
 @article{ransikarbum_kim_ha_wysk_rothrock_2018, title={A Highway-Driving System Design Viewpoint Using an Agent-Based Modeling of an Affordance-Based Finite State Automata}, volume={6}, ISSN={["2169-3536"]}, DOI={10.1109/access.2017.2782257}, abstractNote={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 affordance-based 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.}, journal={IEEE ACCESS}, author={Ransikarbum, Kasin and Kim, Namhun and Ha, Sangho and Wysk, Richard A. and Rothrock, Ling}, year={2018} }
 @article{basinger_keough_webster_wysk_martin_harrysson_2018, title={Development of a modular computer-aided process planning (CAPP) system for additive-subtractive hybrid manufacturing of pockets, holes, and flat surfaces}, volume={96}, ISSN={["1433-3015"]}, DOI={10.1007/s00170-018-1674-x}, number={5-8}, journal={INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY}, author={Basinger, Katie L. and Keough, Carter B. and Webster, Caroline E. and Wysk, Richard A. and Martin, Thomas M. and Harrysson, Ola L.}, year={2018}, month={May}, pages={2407–2420} }
 @article{chung_kremer_wysk_2017, title={A dynamic programming method for product upgrade planning incorporating technology development and end-of-life decisions}, volume={34}, ISSN={["2168-1023"]}, DOI={10.1080/21681015.2016.1192067}, abstractNote={Abstract Product life ends when a product cannot adapt itself to new requirements, such as advances of technology, changes in customers’ preferences, etc. Product upgrade is an effective means to extend the product life, especially for high-investment, low-volume, and long-lifetime products; however, upgrade planning is complex both for product developers and product users. A product upgrade problem can be modeled as a series of decisions over time, and involve trade-offs between product performance and operation costs. These upgrade decisions might also be influenced by future technology changes. This paper proposes a quantitative method based on dynamic programming to help upgrade planners and product users to find an optimal upgrade plan incorporating the forecasts for technology development and end-of-life decisions. Through this method, total useful life cost can be minimized and sustainability can be also improved by upgrading appropriate modules at the right time with minimal impact on the system performance.}, number={1}, journal={JOURNAL OF INDUSTRIAL AND PRODUCTION ENGINEERING}, author={Chung, Wu-Hsun and Kremer, Gul E. Okudan and Wysk, Richard A.}, year={2017}, pages={30–41} }
 @misc{wu_wang_zhang_wysk_chen_2017, title={Bioprinting: an assessment based on manufacturing readiness levels}, volume={37}, ISSN={["1549-7801"]}, DOI={10.3109/07388551.2016.1163321}, abstractNote={Over the last decade, bioprinting has emerged as a promising technology in the fields of tissue engineering and regenerative medicine. With recent advances in additive manufacturing, bioprinting is poised to provide patient-specific therapies and new approaches for tissue and organ studies, drug discoveries and even food manufacturing. Manufacturing Readiness Level (MRL) is a method that has been applied to assess manufacturing maturity and to identify risks and gaps in technology-manufacturing transitions. Technology Readiness Level (TRL) is used to evaluate the maturity of a technology. This paper reviews recent advances in bioprinting following the MRL scheme and addresses corresponding MRL levels of engineering challenges and gaps associated with the translation of bioprinting from lab-bench experiments to ultimate full-scale manufacturing of tissues and organs. According to our step-by-step TRL and MRL assessment, after years of rigorous investigation by the biotechnology community, bioprinting is on the cusp of entering the translational phase where laboratory research practices can be scaled up into manufacturing products specifically designed for individual patients.}, number={3}, journal={CRITICAL REVIEWS IN BIOTECHNOLOGY}, author={Wu, Changsheng and Wang, Ben and Zhang, Chuck and Wysk, Richard A. and Chen, Yi-Wen}, year={2017}, month={May}, pages={333–354} }
 @article{manogharan_wysk_harrysson_2016, title={Additive manufacturing-integrated hybrid manufacturing and subtractive processes: economic model and analysis}, volume={29}, ISSN={["1362-3052"]}, DOI={10.1080/0951192x.2015.1067920}, abstractNote={This article presents economic models for a new hybrid method where additive manufacturing (AM) and subtractive methods (SMs) are integrated through composite process planning. Although AM and SM offer several unique advantages, there are technological limitations such as tolerance and surface finish requirements; tooling and fixturing, etc. that cannot be met by a single type of manufacturing. The intent of this article is not to show a new manufacturing method, but rather to provide economic context to additive and subtractive methods as the best practice provides, and look at the corresponding economics of each of those methods as a function of production batch size, machinability, cost of the material, part geometry and tolerance requirements. Basic models of fixed and variable costs associated with additive, subtractive and hybrid methods to produce parts are also presented. An experimental design is used to study the influence of production volume, material and operating cost, batch size, machinability of the material and impact of reducing AM processing time. A composite response model for the unit cost is computed for the various levels associated with such engineering requirements. The developed models provide insight into how these variables affect the costs associated with engineering a mechanical product that will be produced using AM and SM methods. From the results, it appears that batch size, AM processing time and AM processing cost were the major cost factors. It was shown that the cost of producing ‘near-net’ shape through SM and AM was the decision criteria; which will be critical for tough-to-machine alloys and at multi-batch size.}, number={5}, journal={INTERNATIONAL JOURNAL OF COMPUTER INTEGRATED MANUFACTURING}, author={Manogharan, Guha and Wysk, Richard A. and Harrysson, Ola L. A.}, year={2016}, month={May}, pages={473–488} }
 @inproceedings{shouche_wysk_king_harrysson_2016, title={Supply chain operations reference model for us based powder bed metal additive manufacturing processes}, DOI={10.1109/wsc.2016.7822173}, abstractNote={This paper focuses on modeling the supply chain of an additively manufactured, uniquely customized Total Hip Replacement implant. It explores how the supply chain could be modeled for hip components which are customized for individual patients and produced using additive manufacturing processes. The concept of the SCOR (Supply Chain Operations Reference) model is used to create a formal model of this system. The SCOR model is used to compare the traditional and the AM supply chain on the basis of different performance metrics. The formal supply chain model is used to extract operational activities so that a computer simulation model of the system can be developed. The simulation is used to model system performance so that bottleneck operations can be identified and source needs determined along with a sensitivity analysis to analyze how change in times and resources affect production quantities.}, booktitle={2016 winter simulation conference (wsc)}, author={Shouche, S. and Wysk, R. A. and King, Russell and Harrysson, O. L. A.}, year={2016}, pages={1158–1169} }
 @article{manogharan_wysk_harrysson_aman_2015, title={AIMS – A Metal Additive-hybrid Manufacturing System: System Architecture and Attributes}, volume={1}, ISSN={2351-9789}, url={http://dx.doi.org/10.1016/J.PROMFG.2015.09.021}, DOI={10.1016/J.PROMFG.2015.09.021}, abstractNote={This paper presents an integrated hybrid manufacturing approach to enhance and accelerate the adoption of metal Additive Manufacturing (AM) by adding a direct digital subtractive process to the production that is capable of improving the form, location and position tolerance of critical part features as well as improving surface finish. The hybrid system, AIMS (Additive systems Integrated with subtractive MethodS) can be integrated with existing metal AM systems without any significant modifications. The intent of this paper is to: 1) detail the system architecture, 2) highlight the process requirements, and 3) illustrate the sequential functions from development of CAD models through AM processing, to subtractive post-processing and corresponding process monitoring. Attributes of individual components such as physical and computational requirements associated with each discrete step of the overall process is presented. Advantages and current limitations of AIMS are also noted. The developed models provide insight into how the overall process-flow could be affected by errors (variability) due to both physical and data transfer across multiple systems. This paper also presents a generalized use of AIMS-for a variety of part geometries, noting materials and processing efficiencies associated with this unique hybrid method.}, journal={Procedia Manufacturing}, publisher={Elsevier BV}, author={Manogharan, Guha and Wysk, Richard and Harrysson, Ola and Aman, Ronald}, year={2015}, pages={273–286} }
 @article{srinivasan_harrysson_wysk_2015, title={Automatic part localization in a CNC machine coordinate system by means of 3D scans}, volume={81}, ISSN={["1433-3015"]}, DOI={10.1007/s00170-015-7178-z}, number={5-8}, journal={INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY}, author={Srinivasan, Harshad and Harrysson, Ola L. A. and Wysk, Richard A.}, year={2015}, month={Nov}, pages={1127–1138} }
 @article{hunsberger_harrysson_shirwaiker_starly_wysk_cohen_allickson_yoo_atala_2015, title={Manufacturing Road Map for Tissue Engineering and Regenerative Medicine Technologies}, volume={4}, ISSN={["2157-6580"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84921807245&partnerID=MN8TOARS}, DOI={10.5966/sctm.2014-0254}, abstractNote={Abstract}, number={2}, journal={STEM CELLS TRANSLATIONAL MEDICINE}, author={Hunsberger, Joshua and Harrysson, Ola and Shirwaiker, Ronan and Starly, Binil and Wysk, Richard and Cohen, Paul and Allickson, Julie and Yoo, James and Atala, Anthony}, year={2015}, month={Feb}, pages={130–135} }
 @article{chung_kremer_wysk_2014, title={A Modular Design Approach to Improve Product Life Cycle Performance Based on the Optimization of a Closed-Loop Supply Chain}, volume={136}, ISSN={["1050-0472"]}, DOI={10.1115/1.4025022}, abstractNote={As environmental concerns have grown in recent years, the interest in product design for the life cycle (DFLC) has exhibited a parallel surge. Modular design has the potential to bring life cycle considerations into the product architecture decision-making process, yet most current modular design methods lack the capability for assessing module life cycle consequences in a supply chain. This paper proposes a method for product designers, called the architecture and supply chain evaluation method (ASCEM), to find a product modular architecture with both low life cycle costs and low energy consumption at the early design stages. ASCEM expands the assessment scope from the product's architecture to its supply chain network. This work analyzes the life cycle costs (LCCs) and energy consumption (LCEC) of two products designated within the European Union's directive on waste of electric and electronic equipment (WEEE) within a closed-loop supply chain to identify the most beneficial modular structure. In addition, data on 27 theoretical cases representing various products are analyzed to show the broader applicability of the proposed methodology. Our analysis shows that ASCEM can efficiently identify a good-quality modular structure having low LCC and LCEC in a closed-loop supply chain for both the two tested products and the hypothetical cases.}, number={2}, journal={JOURNAL OF MECHANICAL DESIGN}, author={Chung, Wu-Hsun and Kremer, Guel E. Okudan and Wysk, Richard A.}, year={2014}, month={Feb} }
 @inproceedings{medina_davila_kremer_wysk_2014, title={Design for FDA: A predictive model for the FDA's decision time for medical devices}, DOI={10.1115/detc2013-13606}, abstractNote={The concept of Design for FDA (DfFDA) has a strong basis on the Food and Drug Administration’s (FDA) regulation for medical devices in the Unites States. In fact; an analysis of the factors that impact the time it takes the FDA’s to provide market approval for medical devices, the product design process model, and Design for X (DfX) methods with overlapping FDA objectives lead to the development of DfFDA as a means to increase awareness about regulatory compliance and promote designers to consider the regulations throughout the development process of medical devices. For doing so, the main objective of DfFDA is to provide regulation-focused guidelines to producers of medical devices. An important part of these guidelines and this paper’s major contribution is the development of a prediction model for the FDA’s decision time. Overall, we want this model to become a tool that allows medical device companies to come up with an accurate estimate of a product’s time-to-market after accounting for the FDA’s decision time. In this work, we provide a comparison and discussion on the adequacy of linear regression models and other non-linear models such as parallel and serial tree-based ensembles for prediction the FDA’s decision time.}, booktitle={Proceedings of the ASME International Design Engineering Technical Conferences and Computers and Information in Engineering Conference, 2013, vol 4}, author={Medina, L. A. and Davila, S. and Kremer, G. E. O. and Wysk, R. A.}, year={2014} }
 @article{shirwaiker_wysk_kariyawasam_voigt_carrion_nembhard_2014, title={Interdigitated silver-polymer-based antibacterial surface system activated by oligodynamic iontophoresis - An empirical characterization study}, volume={16}, ISSN={["1572-8781"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84894410919&partnerID=MN8TOARS}, DOI={10.1007/s10544-013-9800-x}, abstractNote={There is a pressing need to control the occurrences of nosocomial infections due to their detrimental effects on patient well-being and the rising treatment costs. To prevent the contact transmission of such infections via health-critical surfaces, a prophylactic surface system that consists of an interdigitated array of oppositely charged silver electrodes with polymer separations and utilizes oligodynamic iontophoresis has been recently developed. This paper presents a systematic study that empirically characterizes the effects of the surface system parameters on its antibacterial efficacy, and validates the system's effectiveness. In the first part of the study, a fractional factorial design of experiments (DOE) was conducted to identify the statistically significant system parameters. The data were used to develop a first-order response surface model to predict the system's antibacterial efficacy based on the input parameters. In the second part of the study, the effectiveness of the surface system was validated by evaluating it against four bacterial species responsible for several nosocomial infections - Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis - alongside non-antibacterial polymer (acrylic) control surfaces. The system demonstrated statistically significant efficacy against all four bacteria. The results indicate that given a constant total effective surface area, the system designed with micro-scale features (minimum feature width: 20 μm) and activated by 15 μA direct current will provide the most effective antibacterial prophylaxis.}, number={1}, journal={BIOMEDICAL MICRODEVICES}, author={Shirwaiker, Rohan A. and Wysk, Richard A. and Kariyawasam, Subhashinie and Voigt, Robert C. and Carrion, Hector and Nembhard, Harriet Black}, year={2014}, month={Feb}, pages={1–10} }
 @article{chung_kremer_wysk_2014, title={Life cycle implications of product modular architectures in closed-loop supply chains}, volume={70}, ISSN={["1433-3015"]}, DOI={10.1007/s00170-013-5409-8}, number={9-12}, journal={INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY}, author={Chung, Wu-Hsun and Kremer, Guel E. Okudan and Wysk, Richard A.}, year={2014}, month={Feb}, pages={2013–2028} }
 @article{joo_kim_wysk_rothrock_son_oh_lee_2013, title={Agent-based simulation of affordance-based human behaviors in emergency evacuation}, volume={32}, ISSN={["1878-1462"]}, DOI={10.1016/j.simpat.2012.12.007}, abstractNote={Complex cognitive processes corresponding to human control behaviors cannot be easily inferred using (1) a logical rule-based model, (2) a statistical model, or (3) an analytical predictive model. Predicting human behaviors in complex and uncertain environments like emergency evacuation is considered almost impossible (at least NP hard) in systems theory. In this paper, we explore simulating human behaviors using affordance-based finite state automata (FSA) modeling, based on the ecological concept of affordance theory. To this end, we introduce the conceptual and generic framework of affordance-based human behavior simulation developed through our previous work. Following the generic framework, formal simulation models of affordance-based human behaviors are developed, especially for emergency evacuation, to mimic perception-based dynamic human actions interacting with emergent environmental changes, such as fire. A “warehouse fire evacuation” case is used to demonstrate the applicability of the proposed framework. The human action planning algorithms in the simulation model are developed and implemented using the Adjusted Floor Field Indicators, which represent not only the evacuee’s prior knowledge of the floor layout but the perceivable information about dynamic environmental changes. The results of our simulation study verify that the proposed framework accurately simulates human fire evacuation behavior. The proposed framework is expected to capture the natural manner in which humans behave in emergency evacuation and enhance the simulation fidelity of analyses and predictions of perceptual human behaviors/responses in the systems by incorporating cognitive intent into human behavior simulations.}, journal={SIMULATION MODELLING PRACTICE AND THEORY}, author={Joo, Jaekoo and Kim, Namhun and Wysk, Richard A. and Rothrock, Ling and Son, Young-Jun and Oh, Yeong-gwang and Lee, Seungho}, year={2013}, month={Mar}, pages={99–115} }
 @misc{shirwaiker_samberg_cohen_wysk_monteiro-riviere_2013, title={Nanomaterials and synergistic low-intensity direct current (LIDC) stimulation technology for orthopedic implantable medical devices}, volume={5}, ISSN={["1939-0041"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-84876463086&partnerID=MN8TOARS}, DOI={10.1002/wnan.1201}, abstractNote={Abstract}, number={3}, journal={WILEY INTERDISCIPLINARY REVIEWS-NANOMEDICINE AND NANOBIOTECHNOLOGY}, author={Shirwaiker, Rohan A. and Samberg, Meghan E. and Cohen, Paul H. and Wysk, Richard A. and Monteiro-Riviere, Nancy A.}, year={2013}, pages={191–204} }
 @article{medina_kremer_wysk_2013, title={Supporting medical device development: a standard product design process model}, volume={24}, ISSN={["1466-1837"]}, DOI={10.1080/09544828.2012.676635}, abstractNote={This article describes the complex nature of the medical device development (MDD) process and presents a product design process model to aid designers engaged in MDD. Basically, the model serves as a conceptual framework and provides a set of formalisms to define the development landscape for medical devices. Specifically, the model describes the phases of MDD and their relationships, including the testing and approval environment that impacts this process. The Food and Drug Administration (FDA) is an essential part of this environment, acting as the regulatory agency for medical devices in the USA. FDA approval is a significant milestone which industry developers must achieve before the actual release of their devices in the US market. In this article, the relevant literature addressing the regulations and the MDD process models are reviewed. The development and organisation of the model are discussed in detail with descriptions of the building process, concepts, granularity, utility and overall contribution. The model is the result of a documentation analysis and is supported by a content validation survey and a case study. The model is proposed as an aid for designers to proactively use in handling the complexities of MDD.}, number={2}, journal={JOURNAL OF ENGINEERING DESIGN}, author={Medina, Lourdes A. and Kremer, Guel E. Okudan and Wysk, Richard A.}, year={2013}, month={Feb}, pages={83–119} }
 @article{yang_wysk_joshi_2012, title={Setup Planning Automation for Six-Axis Wire Electrical Discharge Machining}, volume={134}, ISSN={["1528-8935"]}, DOI={10.1115/1.4005801}, abstractNote={A modern six-axis wire electrical discharge machining (WEDM) system is capable of producing more complex geometries than 2D, 2½D, or ruled surface parts. The rotational axis on a six-axis WEDM system allows a part to be rotated while using a cutting wire to fabricate it. However, limited automation for process planning six-axis WEDM systems requires significant time and effort must be put into process planning. Even with commercially-available computer-aided design (CAD) software, it is difficult to produce process plans for a six-axis WEDM system. Toward automatic development of process plans, a method of determining such setup plans, including the number of setup orientations and rotational axis movements, is presented in this paper. Tangent visibility analysis results presented in our prior research are used to guide the setup, and intermediate coordinate systems are defined in order to classify the tangent visibility results. A greedy algorithm is developed to determine the set of intermediate coordinates and setup orientations for six-axis WEDM.}, number={2}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Yang, Zhi and Wysk, Richard A. and Joshi, Sanjay}, year={2012}, month={Apr} }
 @article{rothrock_wysk_kim_shin_son_joo_2011, title={A modelling formalism for human-machine cooperative systems}, volume={49}, ISSN={["1366-588X"]}, DOI={10.1080/00207543.2010.511637}, abstractNote={This paper presents a collection of models of humans involved in complex systems with a focus on control of the system while allowing human participation in decisions for system operation. The existence of a formal model that captures human behaviour in a complex system allows for the efficient development of modelling and control software of man-machine systems. This paper provides a foundation for modelling and software development for complex systems that includes human activities. A modelling formalism, based on the automata theory for human-machine cooperative systems is demonstrated in this paper in consideration with the ecological concept of affordance.}, number={14}, journal={INTERNATIONAL JOURNAL OF PRODUCTION RESEARCH}, author={Rothrock, Ling and Wysk, Richard and Kim, Namhun and Shin, Dongmin and Son, Young-Jun and Joo, Jaekoo}, year={2011}, pages={4263–4273} }
 @article{yang_wysk_joshi_2011, title={Global Tangent Visibility Analysis for Polyhedral Computer Aided Design Models}, volume={133}, ISSN={["1087-1357"]}, DOI={10.1115/1.4004141}, abstractNote={Visibility analysis is broadly used in milling and casting process planning and in coordinate measuring machine applications. However, standard visibility analysis (which involves determining visibility from a given viewpoint), cannot be applied directly to in-line cutting systems such as wire electrical discharge machines or hot wire foam cutters. The motivation of this paper is to accurately calculate the tangent visibility for objects represented by polygonal surfaces. In this paper we define a new type of visibility - tangent visibility. We develop an algorithm to calculate the global tangent visibility for in-line cutting systems, and several models are tested to verify its accuracy. Several polyhedral models are tested to verify the correctness of the tangent visibility algorithm; and the complexity of the algorithm is also discussed.}, number={3}, journal={JOURNAL OF MANUFACTURING SCIENCE AND ENGINEERING-TRANSACTIONS OF THE ASME}, author={Yang, Zhi and Wysk, Richard A. and Joshi, Sanjay}, year={2011}, month={Jun} }
 @inbook{kim_joo_rothrock_wysk_son_2011, title={Human Behavioral Simulation Using Affordance-Based Agent Model}, ISBN={9783642216015 9783642216022}, ISSN={0302-9743 1611-3349}, url={http://dx.doi.org/10.1007/978-3-642-21602-2_40}, DOI={10.1007/978-3-642-21602-2_40}, abstractNote={In this paper, we propose a novel agent-based simulation modeling of human behaviors. A conceptual framework of human behavioral simulation is suggested using the ecological definition of affordances in order to mimic perception-based human actions interacting with the environment. A simulation example of a ‘warehouse fire evacuation’ is illustrated to demonstrate the applicability of the proposed framework. The perception-based human behaviors and planning algorithms are adapted and embedded within human agent models using the Static and Dynamic Floor Field Indicators, which represent the evacuee’s prior knowledge of the floor layout and perceivable information of dynamic environmental changes, respectively. The proposed framework is expected to capture the natural manners in which humans participate in systems and enhance the simulation fidelity by incorporating cognitive intent into human behavior simulations.}, booktitle={Human-Computer Interaction. Design and Development Approaches}, publisher={Springer Berlin Heidelberg}, author={Kim, Namhun and Joo, Jaekoo and Rothrock, Ling and Wysk, Richard and Son, Young-Jun}, year={2011}, pages={368–377} }
 @article{shirwaiker_wysk_kariyawasam_carrion_voigt_2011, title={Micro-scale fabrication and characterization of a silver-polymer-based electrically activated antibacterial surface}, volume={3}, ISSN={["1758-5090"]}, url={http://www.scopus.com/inward/record.url?eid=2-s2.0-79958266233&partnerID=MN8TOARS}, DOI={10.1088/1758-5082/3/1/015003}, abstractNote={This paper reports the fabrication methodology and characterization results for an electrically activated silver-polymer-based antibacterial surface with primary applications in preventing indirect contact transmission of infections. The surface consists of a micro-scale grating pattern of alternate silver electrodes and SU-8 partitions with a minimum feature size of 20 µm, and activated by an external voltage. In this study, prototype coupons (15 mm × 15 mm) of the antibacterial surface were fabricated on silicon substrates using two sets of lithographies, and analyzed for their physical characteristics using microscopy and surface profilometry. The prototypes were also electrically analyzed to determine their current–voltage characteristics, and hence silver ion (Ag+) release concentrations. Finally, they were tested for their antibacterial efficacy against Staphylococcus aureus (Gram-positive) and Escherichia coli (Gram-negative) using a newly engineered microbiological testing procedure. The antibacterial efficacy testing results show significant reductions in the number of viable organisms of both the species after 45 min of testing with 15 µA system current. Due to the growing incidences of hospital-acquired infections and rising treatment costs, study and application of such alternative antibacterial systems in critical touch-contact and work surfaces (e.g., door push plates, countertops, medical instrument trays) for healthcare environments has become essential.}, number={1}, journal={BIOFABRICATION}, author={Shirwaiker, Rohan A. and Wysk, Richard A. and Kariyawasam, Subhashinie and Carrion, Hector and Voigt, Robert C.}, year={2011}, month={Mar} }
 @article{fuller_wysk_charumani_kennett_sebastiennelli_abrahams_shirwaiker_voigt_royer_2010, title={Developing an engineered antimicrobial/prophylactic system using electrically activated bactericidal metals}, volume={21}, ISSN={0957-4530 1573-4838}, url={http://dx.doi.org/10.1007/S10856-010-4071-Z}, DOI={10.1007/S10856-010-4071-Z}, abstractNote={The increased use of Residual Hardware Devices (RHDs) in medicine combined with antimicrobial resistant-bacteria make it critical to reduce the number of RHD associated osteomyelitic infections. This paper proposes a surface treatment based on ionic emission to create an antibiotic environment that can significantly reduce RHD associated infections. The Kirby-Bauer agar gel diffusion technique was adopted to examine the antimicrobial efficacy of eight metals and their ionic forms against seven microbes commonly associated with osteomyelitis. Silver ions (Ag(+)) showed the most significant bactericidal efficacy. A second set of experiments, designed to identify the best configuration and operational parameters for Ag(+) based RHDs addressed current and ionic concentrations by identifying and optimizing parameters including amperage, cathode and anode length, separation between anode and cathode, and surface charge density. The system demonstrated an unparalleled efficacy. The concept was then implemented during in vitro testing of an antimicrobial hip implant, RHD.}, number={7}, journal={Journal of Materials Science: Materials in Medicine}, publisher={Springer Science and Business Media LLC}, author={Fuller, Thomas A. and Wysk, Richard A. and Charumani, Charumani and Kennett, Mary and Sebastiennelli, Wayne J. and Abrahams, Rachel and Shirwaiker, Rohan A. and Voigt, Robert C. and Royer, Patricia}, year={2010}, month={Apr}, pages={2103–2114} }
 @article{kim_shin_wysk_rothrock_2010, title={Using finite state automata (FSA) for formal modelling of affordances in human-machine cooperative manufacturing systems}, volume={48}, ISSN={0020-7543 1366-588X}, url={http://dx.doi.org/10.1080/00207540802582235}, DOI={10.1080/00207540802582235}, abstractNote={Modelling complex systems poses significant challenges on how one represents the system components and interactions among them. In order to provide a systematic approach to represent human participation as a part of a dynamic system, this paper presents a formal automata model of human-machine cooperative systems that incorporates human capabilities with respect to system conditions. Specifically, we propose a control model for human-involved shop floor systems based on discrete event-based systems (DES) and an environmental concept known as an affordance. When modelling human-involved systems where a human operator is considered a crucial system component, it is necessary to analyse the model complexity that increases significantly due to a human's behavioural patterns. From the perspective of the temporal and physical state domains a human operator's behaviour is usually limited by attention and resource constraints. We investigate these limitations and map them into constrained system affordances, and then construct a formal human-machine cooperative model based on the finite state automaton (FSA) model. The proposed model can provide a framework to combine human activities into systems operations in consideration of human's effectivities and system affordances. A detailed application example is provided to illustrate that the proposed model can effectively be applied to manufacturing control systems.}, number={5}, journal={International Journal of Production Research}, publisher={Informa UK Limited}, author={Kim, N. and Shin, D. and Wysk, R.A. and Rothrock, L.}, year={2010}, month={Mar}, pages={1303–1320} }
 @article{shin_park_kim_wysk_2009, title={A stochastic model for the optimal batch size in multi-step operations with process and product variability}, volume={47}, ISSN={0020-7543 1366-588X}, url={http://dx.doi.org/10.1080/00207540701810778}, DOI={10.1080/00207540701810778}, abstractNote={Virtually all manufacturing processes are subject to variability, an inherent characteristic of most production processes. No two parts can ever be exactly the same in terms of their dimensions. For machining processes such as drilling, milling, and lathing, overall variability is caused in part by machine tools, tooling, fixtures and workpiece material. Since variability, which can be accumulated from tolerance stacking, can result in defective parts the number of parts produced in a batch is limited. When there are too many parts in a batch, the likelihood of producing all acceptable parts in a batch decreases due to the increased tolerances. On the other hand, too small a batch size incurs an increase of manufacturing costs due to frequent setups and tool replacements, whereas the likelihood of acceptable parts increases. To address this challenge, we present a stochastic model for determining the optimal batch size where we consider part-to-part variation in terms of tool wear, which tends to be proportional to batch size. In this paper, a mathematical model is constructed based on the assumption that the process used for producing preceding parts affects the state of subsequent parts in a probabilistic manner.}, number={14}, journal={International Journal of Production Research}, publisher={Informa UK Limited}, author={Shin, D. and Park, J. and Kim, N. and Wysk, R.A.}, year={2009}, month={May}, pages={3919–3936} }
 @article{steele_wysk_ferreira_2008, title={A resource-oriented tolerance representation scheme for the planning of robotic machine tending operations in automated manufacturing systems}, volume={38}, ISSN={0268-3768 1433-3015}, url={http://dx.doi.org/10.1007/S00170-007-1118-5}, DOI={10.1007/S00170-007-1118-5}, number={7-8}, journal={The International Journal of Advanced Manufacturing Technology}, publisher={Springer Science and Business Media LLC}, author={Steele, Jay W. and Wysk, Richard A. and Ferreira, Joao C. E.}, year={2008}, month={Sep}, pages={741–756} }
 @article{altuntas_wysk_rothrock_2007, title={Formal approach to include a human material handler in a computer-integrated manufacturing (CIM) system}, volume={45}, ISSN={0020-7543 1366-588X}, url={http://dx.doi.org/10.1080/00207540500031923}, DOI={10.1080/00207540500031923}, abstractNote={Formal modelling techniques that employ principles of finite state automata have been increasingly used for shop-floor control. These approaches have focused primarily on unmanned systems where the self-contained logic for control of the systems is embedded within the model(s). To date, human operators are seldom configured within the modelling detail required for these systems. The result has been that the interface of humans within automatic systems has been limited. In general, humans performing physical activities in an automatic system must mimic the detailed responses normally transmitted via control computers and equipment, making the human interaction painful and prone to error. This paper discusses (1) the formal modelling specifics required for the control of such an automated shop floor system; and (2) the role and interactions of the human primarily in automatic systems. The human in the automatic manufacturing system addressed here serves primarily as a material handler and material transporter, providing almost unlimited possibilities regarding the accessibility of product flow from any system resource to any other system resource—a major constraint in many operational systems. The impact on the complexity of the accessibility graph, issues related to automatically controlling such a system and the human interactions within such a system are also developed. The paper introduces many complex issues and interactions, and concludes with an example of how a human handler can be effectively included in a finite state automaton.}, number={9}, journal={International Journal of Production Research}, publisher={Informa UK Limited}, author={Altuntas, B. and Wysk, R. A. and Rothrock, L.}, year={2007}, month={May}, pages={1953–1971} }
 @article{lee_son_wysk_2007, title={Simulation-based planning and control: From shop floor to top floor}, volume={26}, ISSN={0278-6125}, url={http://dx.doi.org/10.1016/j.jmsy.2007.07.001}, DOI={10.1016/j.jmsy.2007.07.001}, abstractNote={This paper illustrates how simulation-based shop-floor planning and control can be extended to enterprise-level activities (top floor). First, the general planning and control concept are discussed, followed by an overview of simulation-based shop-floor planning and control. Analogies between the shop floor and top floor are discussed in terms of the components required to construct simulation-based planning and control systems. Analogies are developed for resource models, coordination models, physical entities, and simulation models. Differences between the shop floor and top floor are also discussed in order to identify new challenges faced for top-floor planning and control. A major difference between the top floor and the shop floor is the way a simulation model is constructed for use in planning, depending on whether time synchronization among member simulations becomes an issue or not. Another difference is in the distributed communication/computing platform. This work uses a distributed computing platform using Web services technology to integrate heterogeneous simulations and systems in a distributed top-floor control environment. The research results reveal that simulation-based planning and control is extensible to the top-floor environment’s evolving new research challenges.}, number={2}, journal={Journal of Manufacturing Systems}, publisher={Elsevier BV}, author={Lee, Seungyub and Son, Young-Jun and Wysk, Richard A.}, year={2007}, month={Apr}, pages={85–98} }
 @article{shin_wysk_rothrock_2006, title={A formal control-theoretic model of a human–automation interactive manufacturing system control}, volume={44}, ISSN={0020-7543 1366-588X}, url={http://dx.doi.org/10.1080/00207540500497074}, DOI={10.1080/00207540500497074}, abstractNote={This paper describes a human–automation interactive manufacturing system and presents a formal model for describing and controlling the system. The model presented in this paper considers a system from two perspectives: structural and operational perspectives. Human and an automated controller are considered agents that cooperate to achieve given goals by executing assigned tasks. A human–automation interaction is described with a particular communication model between two agents that exchanges messages. A system control schema and human tasks are modelled separately and then integrated in a formal manner using a modified communicating finite state machine framework. An interface model that coordinates the message exchanges between two agents is then introduced. An automated shop floor control system with a human material handler is modelled with the proposed framework and a simple illustrative example is provided.}, number={20}, journal={International Journal of Production Research}, publisher={Informa UK Limited}, author={Shin, D. and Wysk, R. A. and Rothrock, L.}, year={2006}, month={Oct}, pages={4273–4295} }
 @article{rathore_balaraman_zhao_venkateswaran_son_wysk_2005, title={Development and benchmarking of an epoch time synchronization method for distributed simulation}, volume={24}, ISSN={0278-6125}, url={http://dx.doi.org/10.1016/S0278-6125(05)80008-1}, DOI={10.1016/S0278-6125(05)80008-1}, abstractNote={In this paper, a new epoch time synchronization approach for distributed simulation federates is presented. The approach allows federates in the simulation system to advance their local times at full speed while it is safe to do so. That is, the simulation moves rapidly to the minimum next epoch (interaction) event time, which is calculated using the minimum sojourn time for each federate, and then slows for federation synchronization. The proposed approach is demonstrated using a manufacturing supply chain simulation composed of four distributed federates. Experiments are executed to benchmark the proposed epoch time synchronization method against conventional conservative synchronization methods to show typical improvements for simulation operation. The experimental results reveal that the proposed approach reduces supply chain simulation execution time significantly while maintaining complete accuracy as compared with traditional conservative federation coordination approaches.}, number={2}, journal={Journal of Manufacturing Systems}, publisher={Elsevier BV}, author={Rathore, Adityavijay and Balaraman, Balaji and Zhao, Xiaobing and Venkateswaran, Jayendran and Son, Young-Jun and Wysk, Richard A.}, year={2005}, month={Jan}, pages={69–78} }
 @article{kulvatunyou_wysk_cho_jones_2004, title={Integration framework of process planning based on resource independent operation summary to support collaborative manufacturing}, volume={17}, ISSN={0951-192X 1362-3052}, url={http://dx.doi.org/10.1080/09511920310001607104}, DOI={10.1080/09511920310001607104}, abstractNote={In today's global manufacturing environment, manufacturing functions are distributed as never before. Design, engineering, fabrication, and assembly of new products are done routinely in many different enterprises scattered around the world. Successful business transactions require the sharing of design and engineering data on an unprecedented scale. This paper describes a framework that facilitates the collaboration of engineering tasks, particularly process planning and analysis, to support such globalized manufacturing activities. The information models of data and the software components that integrate those information models are described. The integration framework uses an Integrated Product and Process Data (IPPD) representation called a Resource Independent Operation Summary (RIOS) to facilitate the communication of business and manufacturing requirements. Hierarchical process modelling, process planning decomposition and an augmented AND/OR directed graph are used in this representation. The Resource Specific Process Planning (RSPP) module assigns the required equipment and tools, selects process parameters, and determines manufacturing costs based on two-level hierarchical RIOS data. The shop floor knowledge (resource and process knowledge) and a hybrid approach (heuristic and linear programming) to linearize the AND/OR graph provide the basis for the planning. Finally, a prototype system is developed and demonstrated with an exemplary part. Java and XML (Extensible Mark-up Language) are used to ensure software and information portability.}, number={5}, journal={International Journal of Computer Integrated Manufacturing}, publisher={Informa UK Limited}, author={Kulvatunyou, Boonserm and Wysk, Richard A and Cho, Hyunbo and Jones, Albert}, year={2004}, month={Jul}, pages={377–393} }
 @article{ramakrishnan_wysk_prabhu_2004, title={Prediction of process parameters for intelligent control of tunnel freezers using simulation}, volume={65}, ISSN={0260-8774}, url={http://dx.doi.org/10.1016/j.jfoodeng.2003.05.001}, DOI={10.1016/j.jfoodeng.2003.05.001}, abstractNote={Abstract Various analytical and empirical methods assuming the existence of steady state and requiring homogenous properties of the product have been used with limited success in estimating freezing times in the food processing industry. Irrespective of the method adopted for estimating freezing time requirements, a critical process issue that needs to be considered is that of system control. Simulation models suggest that a feed-forward control strategy, as discussed in this paper, can be used to control a freezing tunnel and obtain considerable energy savings while ensuring `appropriate' freezing of all products. The control strategy discussed in this paper, involves the continuous monitoring of product input and controlling either or both of the refrigerant flow and conveyor speed. The primary objective of this paper is to demonstrate the use of simulation to predict process parameters for `intelligent control' of freezing tunnels, and provide an estimate of potential energy savings.}, number={1}, journal={Journal of Food Engineering}, publisher={Elsevier BV}, author={Ramakrishnan, S. and Wysk, R.A. and Prabhu, V.V.}, year={2004}, month={Nov}, pages={23–31} }
 @article{frank_wysk_joshi_2004, title={Rapid planning for CNC milling—A new approach for rapid prototyping}, volume={23}, ISSN={0278-6125}, url={http://dx.doi.org/10.1016/S0278-6125(04)80037-2}, DOI={10.1016/S0278-6125(04)80037-2}, abstractNote={This paper presents a description of how CNC milling can be used to rapidly machine a variety of parts with minimal human intervention for process planning. The methodology presented uses a layer-based approach (like traditional rapid prototyping) for the rapid, semi-automatic machining of common manufactured part geometries in a variety of materials. Parts are machined using a plurality of 21/2-D toolpaths from orientations about a rotary axis. Process parameters such as the number of orientations, tool containment boundaries, and tool geometry are derived from CAD slice data. In addition, automated fixturing is accomplished through the use of sacrificial support structures added to the CAD geometry. The paper begins by describing the machining methodology and then presents a number of critical issues needed to make the process automatic and efficient. Example parts machined using this methodology are then presented and discussed.}, number={3}, journal={Journal of Manufacturing Systems}, publisher={Elsevier BV}, author={Frank, Matthew C. and Wysk, Richard A. and Joshi, Sanjay B.}, year={2004}, month={Jan}, pages={242–255} }
 @article{pan_wysk_chandra_2001, title={A Statistical Approach to Process Planning}, volume={4}, ISSN={1532-0375}, url={http://dx.doi.org/10.1080/15320370108500215}, DOI={10.1080/15320370108500215}, abstractNote={Abstract This paper presents a formal method for the process planning of machined components using a statistical methodology that can be used in design to determine the percent defective for feature-based tolerance specifications when used in conjunction with a process planning system or more specifically a process tolerance chart. The paper begins with an approach for process selection and then goes through an illustration of a tolerance specification for hole features under a location specification of Regardless of Feature size. Once a formal process plan has been developed, a probability model is used in conjunction with a process tolerance chart to determine the effects of feature size and location specification on percent defective and product cost. A discussion is presented and the model is expanded to include location specification under Maximum Material Condition and Least Material Condition.}, number={1}, journal={Journal of Design and Manufacturing Automation}, publisher={Informa UK Limited}, author={Pan, Rong and Wysk, Richard A. and Chandra, M. Jeya}, year={2001}, month={Oct}, pages={37–46} }