TY - CONF TI - Chemical looping combustion of coal AU - Gupta, P. AU - Velazquez-Vargas, L.G. AU - Li, F. AU - Fan, L.-S. C2 - 2005/// C3 - AIChE Annual Meeting, Conference Proceedings DA - 2005/// VL - 2005 SP - 7620-7625 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33645638139&partnerID=MN8TOARS ER - TY - CONF TI - Hydrogen production from syngas using metal oxide composite particles AU - Velazquez-Vargas, L.G. AU - Gupta, P. AU - Li, F. AU - Fan, L.-S. C2 - 2005/// C3 - AIChE Annual Meeting Conference Proceedings DA - 2005/// VL - 2005 SP - 10119-10122 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33646750981&partnerID=MN8TOARS ER - TY - CONF TI - Implementing Digital Power Control In Automotive Alternators AU - Thondapu, C. AU - Hopkins, D.C. AU - Holguin, G. T2 - Digital Power Forum C2 - 2005/// CY - Boston MA DA - 2005/// PY - 2006/9/12/ ER - TY - JOUR TI - Flip chip solder joint failure modes AU - Basaran, C. AU - Ye, H. AU - Hopkins, D.C. AU - Frear, D. AU - Lin, J.K. T2 - Advanced Packaging DA - 2005/10// PY - 2005/10// VL - 14 IS - 10 SP - 14–19 ER - TY - JOUR TI - The contemporary Asian silver cycle: 1-year stocks and flows AU - Johnson, Jeremiah AU - Bertram, Marlen AU - Henderson, Kathryn AU - Jirikowic, Julie AU - Graedel, T. E. T2 - Journal of Material Cycles and Waste Management DA - 2005/8/20/ PY - 2005/8/20/ DO - 10.1007/s10163-005-0132-7 VL - 7 IS - 2 SP - 93-103 J2 - J Mater Cycles Waste Manag LA - en OP - SN - 1438-4957 1611-8227 UR - http://dx.doi.org/10.1007/s10163-005-0132-7 DB - Crossref ER - TY - JOUR TI - Contemporary Anthropogenic Silver Cycle:  A Multilevel Analysis AU - Johnson, Jeremiah AU - Jirikowic, Julie AU - Bertram, Marlen AU - van Beers, D. AU - Gordon, R. B. AU - Henderson, Kathryn AU - Klee, R. J. AU - Lanzano, Ted AU - Lifset, R. AU - Oetjen, Lucia AU - Graedel, T. E. T2 - Environmental Science & Technology AB - Anthropogenic cycling of silver in 1997 is presented using three discrete governmental units: 64 countries encompassing what we believe to be over 90% of global silver flows, 9 world regions, and the entire planet. Using material flow analysis (MFA) techniques, the country level cycles are aggregated to produce the regional cycles, which are used to form a “best estimate” global cycle. Interesting findings include the following: (1) several silver-mining countries export ore and concentrate but also import silver-containing semiproducts and products; (2) the level of development for a country, as indicated by the gross domestic product, is a fair indicator of silver use, but several significant outliers exist; (3) the countries with the greatest mine production include Mexico, the United States, Peru, and China, whereas the United States, Japan, India, Germany, and Italy lead in the fabrication and manufacture of products; (4) North America and Europe's use of silver products exceed that of other regions on a per capita basis; (5) global silver discards, including tailings and separation waste, totaled approximately 57% of the silver mined; (6) approximately 57% of the silver entering waste management globally is recycled; and (7) the amount of silver entering landfills globally is comparable to the amount found in tailings. The results of this MFA lay the basis for further analysis, which in turn can offer insight into natural resource policy, the characterization of environmental impact, and better resource management. DA - 2005/6// PY - 2005/6// DO - 10.1021/es048319x VL - 39 IS - 12 SP - 4655-4665 J2 - Environ. Sci. Technol. LA - en OP - SN - 0013-936X 1520-5851 UR - http://dx.doi.org/10.1021/es048319x DB - Crossref ER - TY - CONF TI - Modeling deformation in microelectronics BGA solder joints under high current density. Part I. Simulation and testing AU - Ye, Hua AU - Basaran, C. AU - Hopkins, D.C. AU - Lin, Minghui T2 - 2005 55th Electronic Components and Technology Conference AB - In this paper, Moire interferometry technique is used to measure the in-situ displacement evolution of lead-free solder joint under electric current stressing. Large deformation was observed in solder joint under high density (10/sup 4/A/cm/sup 2/) current stressing. The deformation was found to be due to electromigration in the solder joint. An electromigration constitutive model is developed to simulate deformation of lead-free solder joint under current stressing. The simulation predicts reasonably close displacements results to Moire interferometry experimental results in both spatial distribution and time history evolution, which indicates that the electromigration model is reasonably good for predicting the mechanical behavior of lead-free solder alloy under electric current stressing. This is the first part of the papers reporting the deformation of solder joint under current stressing. More experimental results are reported in the second paper. C2 - 2005/7/27/ C3 - Proceedings Electronic Components and Technology, 2005. ECTC '05. DA - 2005/7/27/ DO - 10.1109/ectc.2005.1441975 PB - IEEE SN - 0780389069 UR - http://dx.doi.org/10.1109/ectc.2005.1441975 DB - Crossref ER - TY - BOOK TI - Spaceflight mechanics 2004 : proceedings of the 14th AAS/AIAA Space flight mechanics meeting held 8-12 February 2004, Maui, Hawaii AU - Coffey, S.L. AU - Mazzoleni, A.P. AU - Luu, K.K. AU - Glover, R.A. T2 - Advances in the astronautical sciences DA - 2005/3// PY - 2005/3// SP - 3318 M1 - 119 PB - Univelt for the American Astronautical Society SN - 9780877035152 ER - TY - CONF TI - Dynamic Water Allocation Framework for Multiple uses: Utility of Climate Forecasts towards Short-term Water Management AU - Sankarasubramanian, A. AU - Lall, U. T2 - International conference, Climate Change: A Challenge or a Threat for Water Management A2 - L.J., Bolwidt T3 - Water science & technology C2 - 2005/// C3 - Climate change : a challenge or a threat for water management? : selected proceedings of the International Conference "Climate Change: a Challenge or a Threat for Water Management?" held in Amsterdam, the Netherlands, 27-29 September 2004 CY - Amsterdam, the Netherlands DA - 2005/// PY - 2004/9/27/ ER - TY - SOUND TI - Improved Water Allocation using Climate Information Based Streamflow Forecasts: An Assessment from System Perspective AU - Arumugam, S. DA - 2005/1/24/ PY - 2005/1/24/ ER - TY - SOUND TI - Improved Water Allocation using Climate Information Based Streamflow Forecasts: An Assessment from System Perspective AU - Arumugam, S. DA - 2005/6/24/ PY - 2005/6/24/ ER - TY - SOUND TI - Improving Angat Reservoir Operation using Climate Forecasts: Decision Analyses and Possibilities AU - Arumugam, S. DA - 2005/8/24/ PY - 2005/8/24/ ER - TY - SOUND TI - Decision Systems Research and Tool Development at the IRI AU - Ward, N.M. AU - Hansen, J.W. AU - Arumugam, S. AU - Osgood, D. AU - Zubair, L. AU - Brown, C. AU - Mishra, A. DA - 2005/11/14/ PY - 2005/11/14/ ER - TY - SOUND TI - Climate Forecasts and Reservoir Management – Possibilities and Challenges AU - Arumugam, S. AU - Lall, U. DA - 2005/11/14/ PY - 2005/11/14/ ER - TY - SOUND TI - Climate Information based Streamflow Forecasts: Predictor Identification and Model Development, AU - Arumugam, S. DA - 2005/11/3/ PY - 2005/11/3/ ER - TY - CONF TI - Use of Operational Climate Forecasts in Reservoir Management and Operation AU - Arumugam, S. AU - Lall, U. T2 - American Geophysical Union Fall Meeting C2 - 2005/12// CY - San Francisco, CA DA - 2005/12// PY - 2005/12// ER - TY - SOUND TI - Climate Forecasts and Reservoir Management – Possibilities and Challenges AU - Arumugam, S. DA - 2005/11/14/ PY - 2005/11/14/ ER - TY - SOUND TI - Improved Water Allocation using Climate Information Based Streamflow Forecasts: Decision Analyses and Possibilities AU - Arumugam, S. DA - 2005/10/5/ PY - 2005/10/5/ ER - TY - RPRT TI - Monthly Climate Data for Selected USGS HCDN Sites, 1951-1990, R1 AU - Vogel, R.M. AU - Sankarasubramanian, A. A3 - ORNL Distributed Active Archive Center AB - ORNL DAAC: Time series of monthly minimum and maximum temperature, precipitation, and potential evapotranspiration were derived for 1,469 watersheds in the conterminous United States for which stream flow measurements were also available from the national streamflow database, termed the Hydro-Climatic Data Network (HCDN), developed by Slack et al. (1993a,b). Monthly climate estimates were derived for the years 1951-1990. The climate characteristic estimates of temperature and precipitation were estimated using the PRISM (Daly et al. 1994, 1997) climate analysis system as described in Vogel, et al. 1999. Estimates of monthly potential evaporation were obtained using a method introduced by Hargreaves and Samani (1982) which is based on monthly time series of average minimum and maximum temperature data along with extraterrestrial solar radiation. Extraterrestrial solar radiation was estimated for each basin by computing the solar radiation over 0.1 degree grids using the method introduced by Duffie and Beckman (1980) and then summing those estimates for each river basin. This process is described in Sankarasubramanian, et al. (2001). Revision Notes: This data set has been revised to update the number of watersheds included in the data set and to updated the units for the potential evapotranspiration variable. Please see the Data Set Revisions section of this document for detailed information. DA - 2005/// PY - 2005/// DO - 10.3334/ornldaac/810 M3 - dataset PB - ORNL Distributed Active Archive Center UR - http://daac.ornl.gov/cgi-bin/dsviewer.pl?ds_id=810 ER - TY - JOUR TI - The Costs of Wind's Variability: Is There a Threshold? AU - DeCarolis, Joseph F. AU - Keith, David W. T2 - The Electricity Journal AB - Managing wind's intermittency entails costs even when wind power supplies a small fraction of load. If electric power systems evolve efficiently as wind capacity grows, the costs of managing intermittency will grow smoothly with increasing penetration, allowing wind power to provide deep reductions in CO2 emissions at costs that are competitive with other mitigation options. DA - 2005/1// PY - 2005/1// DO - 10.1016/j.tej.2004.12.006 VL - 18 IS - 1 SP - 69-77 J2 - The Electricity Journal LA - en OP - SN - 1040-6190 UR - http://dx.doi.org/10.1016/j.tej.2004.12.006 DB - Crossref ER - TY - CONF TI - Series connected IGCT based high power three-level neutral point clamped voltage source inverter pole for FACTS applications AU - Bhattacharya, S. AB - This paper reports requirements, issues and design considerations for high power three-level neutral point clamped (NPC) inverter pole. Dynamic voltage sharing issues, viability and advantages of series connected 4.5 kV, 4 kA IGCT for high power 12 MVA three-level NPC inverter pole are investigated. IGCT turn-off tests at high DC voltage and rated current are used for snubber design and inverter pole clamp design, and to verify simulation results. Experimental results are presented for a two 12 MVA three-level NPC inverter poles operated as H-bridge with three series connected 4.5 kV, 4 kA IGCT per switch C2 - 2005/// C3 - PESC Record - IEEE Annual Power Electronics Specialists Conference DA - 2005/// DO - 10.1109/PESC.2005.1581955 VL - 2005 SP - 2315-2321 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33847744335&partnerID=MN8TOARS ER - TY - CONF TI - Variable frequency variable duty cycle operation of the Controlled Capacitor Charging (CCC) type inverter AU - Chakraborty, C. AU - Dalapati, S. AU - Bhattacharya, S. AB - The controlled capacitor charging (CCC) type inverter uses a simple L-C network, where the capacitor (C) that is connected across the load is charged through an inductor (L) connected in series with the load. The charging in such an inverter has to take place in a controlled manner to produce a desired sinusoidal waveform at the output. This paper presents a variable frequency variable duty cycle based charging technique to keep the output voltage within a hysteresis band, while achieving zero-current switching for every pulse at turn-on. The output voltage across the capacitor and the current through the inductor are fed back to the control circuit. An appropriate logic in the controller determines the width of each individual pulse, as well as the frequency of pulses. Extensive simulations in PSPICE have been carried out. A prototype inverter has been fabricated in the laboratory. Excellent correlation between the simulation and experimental results validated the proposed control technique C2 - 2005/// C3 - IECON Proceedings (Industrial Electronics Conference) DA - 2005/// DO - 10.1109/IECON.2005.1568972 VL - 2005 SP - 598-603 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33749681559&partnerID=MN8TOARS ER - TY - CONF TI - Power flow control on 345 kV lines with the 200 MVA convertible static compensator AU - Shperling, B. AU - Sun, J. AU - Bhattacharya, S. AB - A 200 MVA, 345 kV system control FACTS device, consisting of two 100 MVA converters, two 100 MVA high voltage series transformers inserted in 345 kV transmission lines and a 200 MVA shunt transformer, was tested and utilized on a 345 kV network. This device, namely convertible static compensator (CSC), has four basic configurations: static synchronous compensator (STATCOM), static synchronous series compensator (SSSC), unified power flow controller (UPFC), and interline power flow controller (IPFC). The testing confirmed the device capability to operate in multiple configurations and its ability to control and regulate the power flows on two 345 kV transmission lines. The CSC test results confirmed its capability to regulate the substation bus voltage and line power flows under steady-state and dynamic conditions. The CSC flexibility allows to utilize it during normal as well as various emergency system conditions. C2 - 2005/// C3 - 2005 IEEE Russia Power Tech, PowerTech DA - 2005/// DO - 10.1109/PTC.2005.4524832 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-51549116892&partnerID=MN8TOARS ER - TY - CONF TI - Investigation of high temperature operation of the emitter turn-off thyristor AU - Tewari, K. AU - Chen, B. AU - Li, D. AU - Huang, A.Q. AU - Bhattacharya, S. AB - This paper investigates the emitter turn-off thyristor's (ETO's) high temperature operation from thermal stability point of view. The objective is to identify the electrical and thermal limitations to the high temperature application of the ETO. The loss characteristics of the ETO, including switching loss, conduction loss, and leakage loss are studied experimentally and analytically, at high junction temperature. A closed loop thermal system and stability criterion is developed and analyzed. At low junction temperature, the switching loss determines the thermal stability. At high junction temperature, the high leakage loss leads to thermal instability. From the developed thermal system, the maximum operating junction temperature for the ETO has been derived, under certain operating conditions. Steady state operating junction temperature of 160 Degrees Celsius is obtained for the ETO. C2 - 2005/// C3 - IECON Proceedings (Industrial Electronics Conference) DA - 2005/// DO - 10.1109/IECON.2005.1568978 VL - 2005 SP - 633-638 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33749673997&partnerID=MN8TOARS ER - TY - CONF TI - Road grade estimation for on-road vehicle emissions modeling using lidar data AU - Zhang, K. AU - Frey, C. C2 - 2005/// C3 - Proceedings of the Air and Waste Management Association's Annual Conference and Exhibition, AWMA DA - 2005/// VL - 2005 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33646469896&partnerID=MN8TOARS ER - TY - CONF TI - In-use emissions of heavy duty diesel dump trucks on petroleum diesel and B20 biodiesel fuels AU - Frey, H.C. AU - Kim, K. C2 - 2005/// C3 - Proceedings of the Air and Waste Management Association's Annual Conference and Exhibition, AWMA DA - 2005/// VL - 2005 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-33646469610&partnerID=MN8TOARS ER - TY - JOUR TI - Impact of vegetation on sedimentary organic matter composition and polycyclic aromatic hydrocarbon attenuation AU - Gregory, ST AU - Shea, D AU - Guthrie-Nichols, E T2 - ENVIRONMENTAL SCIENCE & TECHNOLOGY AB - Results from natural and engineered phytoremediation systems provide strong evidencethatvegetated soils mitigate polycyclic aromatic hydrocarbon (PAH) contamination. However, the mechanisms by which PAH mitigation occurs and the impact of plant organic matter on PAH attenuation remain unclear. This study assessed the impact of plant organic matter on PAH attenuation in labile and refractory sediments fractions from a petroleum distillate waste pit that has naturally revegetated. Samples were collected in distinct zones of barren and vegetated areas to assess changes to organic matter composition and PAH content as vegetation colonized and became established in the waste pit. Sediments were fractionated into bulk sediment and humin fractions and analyzed for organic matter composition by isotope ratio mass spectrometry (delta (13)C), 13C nuclear magnetic resonance (13C NMR), delta 14C AMS (accelerator mass spectrometry), and percent organic carbon (%TOC). Gas chromatography mass spectrometry (GC/ MS) of lipid extracts of SOM fractions provided data for PAH distribution histograms, compound weathering ratios, and alkylated and nonalkylated PAH concentrations. Inputs of biogenic plant carbon, PAH weathering, and declines in PAH concentrations are most evidentfor vegetated SOM fractions, particularly humin fractions. Sequestered PAH metabolites were also observed in vegetated humin. These results show that plant organic matter does impact PAH attenuation in both labile and refractory fractions of petroleum distillate waste. DA - 2005/7/15/ PY - 2005/7/15/ DO - 10.1021/es048028o VL - 39 IS - 14 SP - 5285-5292 SN - 1520-5851 ER - TY - CONF TI - Looking for a win-win situation: a meta-analysis of poverty and deforestation AU - Atmadja, N. AU - Sills, E. C2 - 2005/// C3 - Proceedings of the Southern Forest Economics Workshop DA - 2005/// ER - TY - JOUR TI - Role of internal nutrient storage in duckweed growth for swine wastewater treatment AU - Chaiprapat, S. AU - Cheng, J. J. AU - Classen, J. J. AU - Liehr, S. K. T2 - Transactions of the ASAE AB - The objective of this study was to investigate the relationship of the nutrient content of duckweed biomass toduckweed growth in swine wastewater. Batch tests of Spirodela punctata 7776, the selected strain for highest total proteinproduction, were conducted in an environment-controlled growth chamber at 24C and 16 h of light per day. A prolongedgrowth period was observed after the nutrients in the medium were exhausted, indicating that duckweed could use its storednutrients for growth. Prediction of growth using medium concentration as an independent variable was deemed unsuitableto describe this growth. Throughout the 30-day growing period, nitrogen and phosphorus content in the biomass varied from59.7 to 19.7 mgN/gbiomass and from 14.8 to 6.8 mgP/gbiomass (dry weight basis), respectively. The relationship between biomassnitrogen content and specific growth rate of Spirodela punctata 7776 was found to follow Monod-type kinetics with .max of0.24 gN/gbiomass/day and KN of 28.8 mgP/gbiomass. Reduced growth rate was observed in the duckweed culture with highduckweed density (mass per unit area). Effects of the duckweed density on growth rate and nutrient uptake are modeled anddiscussed. DA - 2005/// PY - 2005/// DO - 10.13031/2013.20088 VL - 48 IS - 6 SP - 2247-2258 ER - TY - JOUR TI - Low Reynolds number turbulent lifted flames in high co-flow AU - Terry, SD AU - Lyons, KM T2 - COMBUSTION SCIENCE AND TECHNOLOGY AB - ABSTRACT This study presents the results of experiments designed to investigate flame lift-off behavior to nozzle velocity, co-flow velocity, fuel-type, and nozzle size for low Reynolds Number turbulent flows (in and near the hysteresis regime). Local excess jet velocities are computed using jet relations from Tieszen et al. The results show that the local excess jet velocity remains linear with respect to nozzle velocity through most of the hysteresis regime, even though flame lift-off height is not linear. This suggests a non-linear relation not captured by Kalghatgi (Citation1984) for lift-off in the near field and hysteresis regime. Local excess jet velocities at the reattachment point were also computed for flames that are lifted more than three nozzle diameters above the burner. The results show that there is a minimum excess jet velocity for which a flame can stabilize. This minimum velocity is inversely proportional to the laminar burning velocity of the fuel squared. A new relation for lift-off height at the reattachment point for flames in the hysteresis region is derived and compared to experimental data. Keywords: lifted flamespartial premixingflame stabilityflame propagation This research was partially supported by the U.S. Army Research Office (Contract W911NF-05-1-0045), Dr. David Mann, Monitor. DA - 2005/11// PY - 2005/11// DO - 10.1080/00102200500240489 VL - 177 IS - 11 SP - 2091-2112 SN - 1563-521X KW - lifted flames KW - partial premixing KW - flame stability KW - flame propagation ER - TY - JOUR TI - Sensitivity analysis of a two-dimensional probabilistic risk assessment model using analysis of variance AU - Mokhtari, A AU - Frey, HC T2 - RISK ANALYSIS AB - This article demonstrates application of sensitivity analysis to risk assessment models with two‐dimensional probabilistic frameworks that distinguish between variability and uncertainty. A microbial food safety process risk (MFSPR) model is used as a test bed. The process of identifying key controllable inputs and key sources of uncertainty using sensitivity analysis is challenged by typical characteristics of MFSPR models such as nonlinearity, thresholds, interactions, and categorical inputs. Among many available sensitivity analysis methods, analysis of variance (ANOVA) is evaluated in comparison to commonly used methods based on correlation coefficients. In a two‐dimensional risk model, the identification of key controllable inputs that can be prioritized with respect to risk management is confounded by uncertainty. However, as shown here, ANOVA provided robust insights regarding controllable inputs most likely to lead to effective risk reduction despite uncertainty. ANOVA appropriately selected the top six important inputs, while correlation‐based methods provided misleading insights. Bootstrap simulation is used to quantify uncertainty in ranks of inputs due to sampling error. For the selected sample size, differences in F values of 60% or more were associated with clear differences in rank order between inputs. Sensitivity analysis results identified inputs related to the storage of ground beef servings at home as the most important. Risk management recommendations are suggested in the form of a consumer advisory for better handling and storage practices. DA - 2005/12// PY - 2005/12// DO - 10.1111/j.1539-6924.2005.00679.x VL - 25 IS - 6 SP - 1511-1529 SN - 1539-6924 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-31944435421&partnerID=MN8TOARS KW - microbial food safety process risk models KW - sensitivity analysis KW - two-dimensional probabilistic framework KW - uncertainty KW - variability ER - TY - JOUR TI - High levels of nitrifying bacteria in intermittently aerated reactors treating high ammonia wastewater AU - Mota, C AU - Ridenoure, J AU - Cheng, JY AU - Reyes, FL T2 - FEMS MICROBIOLOGY ECOLOGY AB - Changes in the fractions of ammonia-oxidizing bacteria and nitrite-oxidizing bacteria in two laboratory-scale reactors were investigated using 16S rRNA probe hybridizations. The reactors were operated in intermittent aeration mode and different aeration cycles to treat anaerobically digested swine wastewater with ammonia concentrations up to 175 mg NH3-N/L. High ammonia removals (>98.8%) were achieved even with increased nitrogen loads and lower aeration: non-aeration time ratios of 1 h:3 h. Nitrosomonas/Nitrosococcus mobilis were the dominant ammonia-oxidizing bacteria in the reactors. Nitrospira-like organisms were the dominant nitrite-oxidizing bacteria during most of the investigation, but were occasionally outcompeted by Nitrobacter. High levels of nitrifiers were measured in the biomass of both reactors, and ammonia-oxidizing bacteria and nitrite-oxidizing bacterial levels adjusted to changing aeration: non-aeration time ratios. Theoretical ammonia-oxidizer fractions, determined by a mathematical model, were comparable to the measured values, although the measured biomass fractions were different at each stage while the theoretical values remained approximately constant. Stable ammonia removals and no nitrite accumulation were observed even when rRNA levels of ammonia oxidizers and nitrite-oxidizers reached a minimum of 7.2% and 8.6% of total rRNA, respectively. Stable nitrogen removal performance at an aeration: non-aeration ratio of 1 h:3 h suggests the possibility of significant savings in operational costs. DA - 2005/11/1/ PY - 2005/11/1/ DO - 10.1016/j.femsec.2005.05.001 VL - 54 IS - 3 SP - 391-400 SN - 1574-6941 KW - ammonia oxidizing bacteria KW - nitrite oxidizing bacteria KW - nitrification KW - oligonucleotide probes KW - intermittent aeration KW - swine wastewater ER - TY - JOUR TI - Fault analysis on distribution feeders with distributed generators AU - Baran, ME AU - El-Markaby, I T2 - IEEE TRANSACTIONS ON POWER SYSTEMS AB - This paper shows that the current an inverter interfaced distributed generator (IIDG) contributes to a fault varies considerably, due mainly to fast response of its controller. This paper proposes a method to extend the conventional fault analysis methods so that IIDG contribution can be estimated in the fault analysis. The proposed method gives rms profiles of the fault currents of interest (IIDG contribution and the fault currents the protective device will see). Test results, based on a prototype feeder, show that the proposed approach can estimate the fault current's contributions under both balanced and unbalanced fault conditions. DA - 2005/11// PY - 2005/11// DO - 10.1109/TPWRS.2005.857940 VL - 20 IS - 4 SP - 1757-1764 SN - 1558-0679 KW - distributed generation KW - distribution system KW - fault analysis ER - TY - JOUR TI - Effects of aeration cycles on nitrifying bacterial populations and nitrogen removal in intermittently aerated reactors AU - Mota, C AU - Head, MA AU - Ridenoure, JA AU - Cheng, JJ AU - Reyes, FL T2 - APPLIED AND ENVIRONMENTAL MICROBIOLOGY AB - ABSTRACT The effects of the lengths of aeration and nonaeration periods on nitrogen removal and the nitrifying bacterial community structure were assessed in intermittently aerated (IA) reactors treating digested swine wastewater. Five IA reactors were operated in parallel with different aeration-to-nonaeration time ratios (ANA). Populations of ammonia-oxidizing bacteria (AOB) and nitrite-oxidizing bacteria (NOB) were monitored using 16S rRNA slot blot hybridizations. AOB species diversity was assessed using amoA gene denaturant gradient gel electrophoresis. Nitrosomonas and Nitrosococcus mobilis were the dominant AOB and Nitrospira spp. were the dominant NOB in all reactors, although Nitrosospira and Nitrobacter were also detected at lower levels. Reactors operated with the shortest aeration time (30 min) showed the highest Nitrosospira rRNA levels, and reactors operated with the longest anoxic periods (3 and 4 h) showed the lowest levels of Nitrobacter , compared to the other reactors. Nitrosomonas sp. strain Nm107 was detected in all reactors, regardless of the reactor's performance. Close relatives of Nitrosomonas europaea , Nitrosomonas sp. strain ENI-11, and Nitrosospira multiformis were occasionally detected in all reactors. Biomass fractions of AOB and effluent ammonia concentrations were not significantly different among the reactors. NOB were more sensitive than AOB to long nonaeration periods, as nitrite accumulation and lower total NOB rRNA levels were observed for an ANA of 1 h:4 h. The reactor with the longest nonaeration time of 4 h performed partial nitrification, followed by denitrification via nitrite, whereas the other reactors removed nitrogen through traditional nitrification and denitrification via nitrate. Superior ammonia removal efficiencies were not associated with levels of specific AOB species or with higher AOB species diversity. DA - 2005/12// PY - 2005/12// DO - 10.1128/AEM.71.12.8565-8572.2005 VL - 71 IS - 12 SP - 8565-8572 SN - 1098-5336 ER - TY - JOUR TI - Dilute acid pretreatment of rye straw and bermudagrass for ethanol production AU - Sun, Y AU - Cheng, JJ T2 - BIORESOURCE TECHNOLOGY AB - Ethanol production from lignocellulosic materials provides an alternative energy production system. Rye and bermudagrass that are used in hog farms for nutrient uptake from swine wastewater have the potential for fuel ethanol production because they have a relative high cellulose and hemicellulose content. Dilute sulfuric acid pretreatment of rye straw and bermudagrass before enzymatic hydrolysis of cellulose was investigated in this study. The biomass at a solid loading rate of 10% was pretreated at 121 degrees C with different sulfuric acid concentrations (0.6, 0.9, 1.2 and 1.5%, w/w) and residence times (30, 60, and 90 min). Total reducing sugars, arabinose, galactose, glucose, and xylose in the prehydrolyzate were analyzed. In addition, the solid residues were hydrolyzed by cellulases to investigate the enzymatic digestibility. With the increasing acid concentration and residence time, the amount of arabinose and galactose in the filtrates increased. The glucose concentration in the prehydrolyzate of rye straw was not significantly influenced by the sulfuric acid concentration and residence time, but it increased in the prehydrolyzate of bermudagrass with the increase of pretreatment severity. The xylose concentration in the filtrates increased with the increase of sulfuric acid concentration and residence time. Most of the arabinan, galactan and xylan in the biomass were hydrolyzed during the acid pretreatment. Cellulose remaining in the pretreated feedstock was highly digestible by cellulases from Trichoderma reesei. DA - 2005/9// PY - 2005/9// DO - 10.1016/j.biortech.2004.12.022 VL - 96 IS - 14 SP - 1599-1606 SN - 1873-2976 KW - bermudagrass KW - cellulases KW - enzymatic hydrolysis KW - ethanol production KW - rye straw KW - sulfuric acid pretreatment ER - TY - JOUR TI - Recommended practice regarding selection of sensitivity analysis methods applied to microbial food safety process risk models AU - Mokhtari, A AU - Frey, HC T2 - HUMAN AND ECOLOGICAL RISK ASSESSMENT AB - ABSTRACT A guideline is presented for selection of sensitivity analysis methods applied to microbial food safety process risk (MFSPR) models. The guideline provides useful boundaries and principles for selecting sensitivity analysis methods for MSFPR models. Although the guideline is predicated on a specific branch of risk assessment models related to food-borne diseases, the principles and recommendations provided are typically generally applicable to other types of risk models. Applicable situations include: prioritizing potential critical control points; identifying key sources of variability and uncertainty; and refinement, verification, and validation of a model. Based on the objective of the analysis, characteristics of the model under study, amount of detail expected from sensitivity analysis, and characteristics of the sensitivity analysis method, recommendations for selection of sensitivity analysis methods are provided. A decision framework for method selection is introduced. The decision framework can substantially facilitate the process of selecting a sensitivity analysis method. DA - 2005/6// PY - 2005/6// DO - 10.1080/10807030590949672 VL - 11 IS - 3 SP - 591-605 SN - 1549-7860 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-22244443715&partnerID=MN8TOARS KW - sensitivity analysis KW - microbial food safety process risk model KW - variability KW - uncertainty ER - TY - JOUR TI - Quantitative analysis of variability and uncertainty with known measurement error: Methodology and case study AU - Zheng, JY AU - Frey, HC T2 - RISK ANALYSIS AB - The appearance of measurement error in exposure and risk factor data potentially affects any inferences regarding variability and uncertainty because the distribution representing the observed data set deviates from the distribution that represents an error‐free data set. A methodology for improving the characterization of variability and uncertainty with known measurement errors in data is demonstrated in this article based on an observed data set, known measurement error, and a measurement‐error model. A practical method for constructing an error‐free data set is presented and a numerical method based upon bootstrap pairs, incorporating two‐dimensional Monte Carlo simulation, is introduced to address uncertainty arising from measurement error in selected statistics. When measurement error is a large source of uncertainty, substantial differences between the distribution representing variability of the observed data set and the distribution representing variability of the error‐free data set will occur. Furthermore, the shape and range of the probability bands for uncertainty differ between the observed and error‐free data set. Failure to separately characterize contributions from random sampling error and measurement error will lead to bias in the variability and uncertainty estimates. However, a key finding is that total uncertainty in mean can be properly quantified even if measurement and random sampling errors cannot be separated. An empirical case study is used to illustrate the application of the methodology. DA - 2005/6// PY - 2005/6// DO - 10.1111/j.1539-6924.2005.00620.x VL - 25 IS - 3 SP - 663-675 SN - 1539-6924 UR - http://www.scopus.com/inward/record.url?eid=2-s2.0-23644460458&partnerID=MN8TOARS KW - bootstrap pair KW - error-free data KW - measurement error KW - observed data KW - uncertainty KW - variability ER - TY - JOUR TI - Land use and income diversification: comparing traditional and colonist populations in the Brazilian Amazon AU - Caviglia-Harris, JL AU - Sills, EO T2 - AGRICULTURAL ECONOMICS AB - Abstract This article compares and analyzes land use and income diversification among two distinct groups of farmers in the Brazilian Amazon: recent colonists in Ouro Preto do Oeste, Rondônia, and traditional long‐term residents along the Tapajós River, Pará. We investigate the hypothesis that farmers who diversify their cash income sources clear less forest on an annual basis, and we compare these livelihood choices across colonist and traditional populations. In particular, we develop a conceptual model based on the household production framework and use econometric models to identify determinants of diversification and forest clearing. We find that diversification of agricultural cash crops is negatively correlated with forest clearing by colonists, providing limited evidence for the hypothesis. Other significant covariates of diversification and forest clearing include cash income levels, stage in family life cycle, cattle ownership, and chemical inputs. Differences in these variables, and differences in household response to these variables, explain variation in diversification and forest clearing across the two populations. DA - 2005/5// PY - 2005/5// DO - 10.1111/j.1574-0862.2005.00238.x VL - 32 IS - 3 SP - 221-237 SN - 1574-0862 KW - income diversification KW - deforestation KW - land use KW - Amazon KW - Brazil KW - household production ER - TY - CONF TI - Intermittent aeration for nitrogen removal from high-ammonia wastewater through nitrification and denitrification in a single reactor AU - Head, M. A. AU - Mota, C. R. AU - Ridenoure, J. A., III AU - Reyes F. L., AU - Cheng, J. J. C2 - 2005/// C3 - 2005 Animal Waste Management Symposium (Research Triangle, NC) DA - 2005/// ER - TY - JOUR TI - Using intermittent aeration to remove nitrogen from swine wastewater AU - Head, M. A. AU - Ridenoure, J. A. AU - Mota, C. R., III AU - Reyes F. L., AU - Cheng, J. J. T2 - Industrial Wastewater DA - 2005/// PY - 2005/// VL - 4 IS - 4 SP - 9-12 ER - TY - CONF TI - Nitrogen removing activity of granules in intermittent aeration reactors treating high-ammonia wastewater AU - Head, M. A. AU - Williams, J. C. AU - Mota, C. R., III AU - Reyes F. L., AU - Cheng, J. J. C2 - 2005/// C3 - 4th International Water Association Specialized Conference on Microorganisms in Activated Sludge and Biofilm Systems (Gold Coast, Australia) DA - 2005/// ER - TY - CONF TI - Nitrogen removal from anaerobically pretreated swine wastewater in an intermittent aeration process AU - Head, M. A. AU - Mota, C. R. AU - Ridenoure, J. A. AU - Reyes F. L., AU - Cheng, J. J. AB - Intermittent aeration (IA) process was investigated for nitrogen removal from anaerobically pretreatedswine wastewater (APTSW) that contained a high concentration of ammonium (average 265 mgNH4-N/l) and a low sCOD (soluble chemical oxygen demand)/N ratio (average 1.4). Nitrogen removal from theAPTSW was achieved through nitrification and denitrification in a single, semi-continuously fed reactor that wasoperated with alternation of aeration and non-aeration at room temperature (23oC). To optimize the IAprocess, different Aeration:Non-Aeration (ANA) ratios and cycle lengths were used in the reactors as follows:Reactor A, l hour : 1 hour; Reactor B, 1 hour : 3 hours; Reactor C, 0.5 hour : 1.5 hours; Reactor D, 0.5 hour : 2hour; Reactor E, 1 hour : 4 hours; Reactor F, 1 hour : 5 hours; and Reactor G, 1 hour : 6 hours. The hydraulicretention time (HRT) and mean cell residence time (MCRT) for the reactors were 3 and 20 days, respectively.Over 79 % ammonium was removed in all of the reactors. The reactor with the highest ANA ratio (Reactor A)achieved the highest NH3-N removal (99%), while the reactor with the longest non-aeration period (Reactor F)achieved the highest total nitrogen removal (83%). It was found that nitrogen removal was achieved throughnitrate denitrification in Reactors A, B, C, and D, but it was via nitrite reduction in Reactors E and F. The highnitrogen removal efficiency indicated that the required organic carbon must have been obtained from thesolubilization of solids contained in the influent or from microbial decay byproducts. The substantially higherdenitrification rates observed in Reactors E and F were likely due to the decreased sCOD requirements fornitrogen removal via nitrite versus those required via nitrate. C2 - 2005/// C3 - 2005 ASAE Annual International Meeting: Tampa Convention Center, Tampa, Florida, 17 - 20 July 2005 DA - 2005/// DO - 10.13031/2013.19488 ER - TY - JOUR TI - Anaerobic processes in waste treatment AU - Chen, Ye AU - Cheng, Jay J. T2 - WATER ENVIRONMENT RESEARCH AB - Water Environment ResearchVolume 77, Issue 6 p. 1347-1388 Treatment SystemFree Access Anaerobic Processes in Waste Treatment Ye Chen, Ye ChenSearch for more papers by this authorJay J. Cheng, Jay J. ChengSearch for more papers by this author Ye Chen, Ye ChenSearch for more papers by this authorJay J. Cheng, Jay J. ChengSearch for more papers by this author First published: 01 October 2005 https://doi.org/10.2175/106143005X54407Citations: 4AboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onFacebookTwitterLinked InRedditWechat Citing Literature Volume77, Issue62005 Literature ReviewSeptember-October 2005Pages 1347-1388 RelatedInformation DA - 2005/// PY - 2005/// DO - 10.2175/106143005X54407 VL - 77 IS - 6 SP - 1347-1388 SN - 1554-7531 ER - TY - JOUR TI - Load estimation for load monitoring at distribution substations AU - Baran, ME AU - Freeman, LAA AU - Hanson, F AU - Ayers, V T2 - IEEE TRANSACTIONS ON POWER SYSTEMS AB - This paper addresses the issues related to the real-time monitoring of loads at distribution substations. A method is proposed for estimating the measurements that become unavailable due to metering problems. To address the low redundancy associated with the load monitoring scheme, the method uses a regression-based model and makes use of the strong correlation between the loads that are geographically close to each other. The method was tested with actual field data. The results indicate that the method has the acceptable performance for measurement loss of up to a week. The average estimation error varies 2-7.5%, depending on which measurement is lost and how up-to-date the historical data is. DA - 2005/2// PY - 2005/2// DO - 10.1109/TPWRS.2004.840409 VL - 20 IS - 1 SP - 164-170 SN - 0885-8950 KW - load estimation KW - power distribution KW - power system monitoring ER -