WorldWideScience

Sample records for performance simulation mapps

  1. Maintenance personnel performance simulation (MAPPS) model: overview and evaluation efforts

    International Nuclear Information System (INIS)

    Knee, H.E.; Haas, P.M.; Siegel, A.I.; Bartter, W.D.; Wolf, J.J.; Ryan, T.G.

    1984-01-01

    The development of the MAPPS model has been completed and the model is currently undergoing evaluation. These efforts are addressing a number of identified issues concerning practicality, acceptability, usefulness, and validity. Preliminary analysis of the evaluation data that has been collected indicates that MAPPS will provide comprehensive and reliable data for PRA purposes and for a number of other applications. The MAPPS computer simulation model provides the user with a sophisticated tool for gaining insights into tasks performed by NPP maintenance personnel. Its wide variety of input parameters and output data makes it extremely flexible for application to a number of diverse applications. With the demonstration of favorable model evaluation results, the MAPPS model will represent a valuable source of NPP maintainer reliability data and provide PRA studies with a source of data on maintainers that has previously not existed

  2. Maintenance Personnel Performance Simulation (MAPPS) model

    International Nuclear Information System (INIS)

    Siegel, A.I.; Bartter, W.D.; Wolf, J.J.; Knee, H.E.; Haas, P.M.

    1984-01-01

    A stochastic computer model for simulating the actions and behavior of nuclear power plant maintenance personnel is described. The model considers personnel, environmental, and motivational variables to yield predictions of maintenance performance quality and time to perform. The mode has been fully developed and sensitivity tested. Additional evaluation of the model is now taking place

  3. Maintenance Personnel Performance Simulation (MAPPS) model: description of model content, structure, and sensitivity testing. Volume 2

    International Nuclear Information System (INIS)

    Siegel, A.I.; Bartter, W.D.; Wolf, J.J.; Knee, H.E.

    1984-12-01

    This volume of NUREG/CR-3626 presents details of the content, structure, and sensitivity testing of the Maintenance Personnel Performance Simulation (MAPPS) model that was described in summary in volume one of this report. The MAPPS model is a generalized stochastic computer simulation model developed to simulate the performance of maintenance personnel in nuclear power plants. The MAPPS model considers workplace, maintenance technician, motivation, human factors, and task oriented variables to yield predictive information about the effects of these variables on successful maintenance task performance. All major model variables are discussed in detail and their implementation and interactive effects are outlined. The model was examined for disqualifying defects from a number of viewpoints, including sensitivity testing. This examination led to the identification of some minor recalibration efforts which were carried out. These positive results indicate that MAPPS is ready for initial and controlled applications which are in conformity with its purposes

  4. Maintenance Personnel Performance Simulation (MAPPS) model: a human reliability analysis tool

    International Nuclear Information System (INIS)

    Knee, H.E.

    1985-01-01

    The Maintenance Personnel Performance Simulation (MAPPS) model is a computerized, stochastic, task-oriented human behavioral model developed to provide estimates of nuclear power plant (NPP) maintenance team performance measures. It is capable of addressing person-machine, person-environment, and person-person relationships, and accounts for interdependencies that exist between the subelements that make up the maintenance task of interest. The primary measures of performance estimated by MAPPS are: (1) the probability of successfully completing the task of interest; and (2) the task duration time. MAPPS also estimates a host of other performance indices, including the probability of an undetected error, identification of the most- and least-likely error-prone subelements, and maintenance team stress profiles during task execution. The MAPPS model was subjected to a number of evaluation efforts that focused upon its practicality, acceptability, usefulness, and validity. Methods used for these efforts included a case method approach, consensus estimation, and comparison with observed task performance measures at a NPP. Favorable results, such as close agreement between task duration times for two tasks observed in the field (67.0 and 119.8 minutes, respectively), and estimates by MAPPS (72.0 and 124.0 minutes, respectively) enhance the confidence in the future use of MAPPS. 8 refs., 1 fig

  5. MAPPS (Maintenance Personnel Performance Simulation): a computer simulation model for human reliability analysis

    International Nuclear Information System (INIS)

    Knee, H.E.; Haas, P.M.

    1985-01-01

    A computer model has been developed, sensitivity tested, and evaluated capable of generating reliable estimates of human performance measures in the nuclear power plant (NPP) maintenance context. The model, entitled MAPPS (Maintenance Personnel Performance Simulation), is of the simulation type and is task-oriented. It addresses a number of person-machine, person-environment, and person-person variables and is capable of providing the user with a rich spectrum of important performance measures including mean time for successful task performance by a maintenance team and maintenance team probability of task success. These two measures are particularly important for input to probabilistic risk assessment (PRA) studies which were the primary impetus for the development of MAPPS. The simulation nature of the model along with its generous input parameters and output variables allows its usefulness to extend beyond its input to PRA

  6. Maintenance Personnel Performance Simulation (MAPPS) model. Users' Manual

    International Nuclear Information System (INIS)

    Kopstein, F.F.; Wolf, J.J.

    1985-09-01

    This report (MAPPS User's Manual) is the last report to be published from this program and provides detailed guidelines for utilization of the MAPPS model. Although the model has been developed to be highly user-friendly and provides interactive means for controlling and running of the model, the user's manual is provided as a guide for the user in the event clarification or direction is required. The user will find that in general the model requires primarily user input that is self explanatory. Once initial familiarization with the model has been achieved by the user, the amount of interaction between the user's manual and the computer model will be minimal. It is suggested however that even the experienced user keep the user's manual handy for quick reference. 5 refs., 10 figs., 7 tabs

  7. The Maintenance Personnel Performance Simulation (MAPPS) model: A human reliability analysis tool

    International Nuclear Information System (INIS)

    Knee, H.E.

    1985-01-01

    The Maintenance Personnel Performance Simulation (MAPPS) model is a computerized, stochastic, task-oriented human behavioral model developed to provide estimates of nuclear power plant (NPP) maintenance team performance measures. It is capable of addressing person-machine, person-environment, and person-person relationships, and accounts for interdependencies that exist between the subelements that make up the maintenance task of interest. The primary measures of performance estimated by MAPPS are: 1) the probability of successfully completing the task of interest and 2) the task duration time. MAPPS also estimates a host of other performance indices, including the probability of an undetected error, identification of the most- and least-likely error-prone subelements, and maintenance team stress profiles during task execution

  8. Maintenance personnel performance simulation (MAPPS): a model for predicting maintenance performance reliability in nuclear power plants

    International Nuclear Information System (INIS)

    Knee, H.E.; Krois, P.A.; Haas, P.M.; Siegel, A.I.; Ryan, T.G.

    1983-01-01

    The NRC has developed a structured, quantitative, predictive methodology in the form of a computerized simulation model for assessing maintainer task performance. Objective of the overall program is to develop, validate, and disseminate a practical, useful, and acceptable methodology for the quantitative assessment of NPP maintenance personnel reliability. The program was organized into four phases: (1) scoping study, (2) model development, (3) model evaluation, and (4) model dissemination. The program is currently nearing completion of Phase 2 - Model Development

  9. An In-situ materials analysis particle probe (MAPP) diagnostic to study particle density control and hydrogenic fuel retention in NSTX

    Energy Technology Data Exchange (ETDEWEB)

    Allain, Jean-Paul [Purdue Univ., West Lafayette, IN (United States)

    2014-09-05

    A new materials analysis particle probe (MAPP) was designed, constructed and tested to develop understanding of particle control and hydrogenic fuel retention in lithium-based plasma-facing surfaces in NSTX. The novel feature of MAPP is an in-situ tool to probe the divertor NSTX floor during LLD and lithium-coating shots with subsequent transport to a post-exposure in-vacuo surface analysis chamber to measure D retention. In addition, the implications of a lithiated graphite-dominated plasma-surface environment in NSTX on LLD performance, operation and ultimately hydrogenic pumping and particle control capability are investigated in this proposal. MAPP will be an invaluable tool for erosion/redeposition simulation code validation.

  10. Conversion of a mainframe simulation for maintenance performance to a PC environment

    International Nuclear Information System (INIS)

    Gertman, D.I.

    1991-01-01

    A computer-based simulation capable of generating human error probabilities (HEPs) for maintenance activities is presented. The HEPs are suitable for use in probabilistic risk assessments (PRAs) and are an important source of information for data management systems such as NUCLARR- the Nuclear Computerized Library for Assessing Reactor Reliability. (1) The basic computer model MAPPS--the maintenance personnel performance simulation has been developed and validated by the US NRC in order to improve maintenance practices and procedures at nuclear power plants. This model validated previously, has now been implemented and improved, in a PC environment, and renamed MicroMAPPS. The model is stochastically based, able to simulate the performance of 2 to 15 person crews for a variety of maintenance conditions. These conditions include aspects of crew actions as potentially influenced by the task, the environment, or characteristics of the personnel involved. The nature of the software code makes it particularly appropriate for determining changes in HEP rates due to fluctuations in important task, environment,. or personnel parameters. The presentation presents a brief review of the mainframe version of the code and presents a summarization of the enhancements which dramatically change the nature of the human computer interaction

  11. Microlearning mApp raises health competence : Hybrid service design

    NARCIS (Netherlands)

    Simons, L.P.A.; Foerster, F.; Bruck, P.A.; Motiwalla, L.; Jonker, C.M.

    2015-01-01

    Work place health support interventions can help support our aging work force, with mApps offering cost-effectiveness opportunities. Previous research shows that health support apps should offer users enough newness and relevance each time they are used. Otherwise the ‘eHealth law of attrition’

  12. Conversion of a mainframe simulation for maintenance performance to a PC environment

    International Nuclear Information System (INIS)

    Gertman, D.I.

    1990-01-01

    The computer model MAPPS, the Maintenance Personnel Performance Simulation, has been developed and validated by the US NRC [Nuclear Regulatory Commission] in order to improve maintenance practices and procedures at nuclear power plants. This model has now been implemented and improved, in a PC [personal computer] environment and renamed MICROMAPPS. The model is stochastically based and users are able to simulate the performance of 2- to 8-person crews for a variety of maintenance tasks under a variety of conditions. These conditions include aspects of crew actions as potentially influenced by the task, the environment, or the personnel involved. For example, the influence of the following factors is currently modeled within the MAPPS computer code: (1) personnel characteristics include but are not limited to intellectual and perceptual motor ability levels, the effect of fatigue and conversely, of rest breaks on performance, stress, communication, supervisor acceptance, motivation, organizational climate, time since the tasks was last performed and the staffing level available; (2) task variables include but are not limited to time allowed, occurrence of shift change, intellectual requirements, perceptual motor requirements, procedures quality, necessity for protective clothing and essentiality of a procedures quality, necessity for protective clothing and essentiality of a subtask; and (3) environment variables include temperature of the workplace, radiation level, and noise levels. The output describing maintainer performance includes subtask and task identification, success proportion, work and wait durations, time spent repeating various subtasks and outcome in terms of errors detected by the crew, false alarms, undetected errors, duration, and the probability of success. The model is comprehensive and allows for the modeling of decision making, trouble-shooting and branching of tasks

  13. Lasertron performance simulation

    International Nuclear Information System (INIS)

    Dubrovin, A.; Coulon, J.P.

    1987-05-01

    This report presents a comparative simulation study of the Lasertron at different frequency and emission conditions, in view to establish choice criteria for future experiments. The RING program for these simulations is an improved version of the one presented in an other report. The self-consistent treatment of the R.F. extraction zone is added to it, together with the possibility to vary initial conditions to better describe the laser illumination and the electron extraction from cathode. Plane or curved cathodes are used [fr

  14. MappERS-C and MappERS-V. The crowd source for prevention and crisis support

    Science.gov (United States)

    Frigerio, Simone; Schenato, Luca; Bianchizza, Chiara; Del Bianco, Daniele

    2015-04-01

    The responsibilities within natural hazards at local/regional levels involve citizens and volunteers as first actors of civil protection and territorial management. The prevention implicates the capacities of professional operators and technical volunteers, but the priority implies now the involvement and awareness of the citizens over the territory they inhabit. The involvement of population creates context-specific strategies of territorial surveillance and management, skipping the limit to face risks only when they have to bear impacts on their lives. MAppERS (Mobile Application for Emergency Response and Support) is a EU project (funded under programme 2013-2015 Humanitarian Aid and Civil Protection, ECHO A5) which empowers "crowd-sourced mappers" through smart phone applications and sensors, with geo-tagged information, detailed gathered parameters, field-check survey in a contest of geospatial response. The process of development includes feedback from citizens, involving them in training courses on the monitoring as long term objective (raising public awareness and participation). The project deals with the development and testing of the smart phone applications (module MAppERS-V for volunteers, module MAppERS-C for citizens) according to Android SDK environment. A first research described a desk-based investigation on consequences of disasters impacts and costs of prevention strategies in pilot countries. Furthermore a review of state-of-the-art of database management systems (DBMS) in pilot countries and involvement of volunteers/citizens in data collection/monitoring collected basic info on data structure for the development. A desk-based research proposed communication methods/graphic solutions within mobile technologies for disaster management in pilot countries and available smartphone applications linked to centralized web/server database. A technical review is compulsory for a useful design-line for MappERS development, and it is linked with on

  15. High performance electromagnetic simulation tools

    Science.gov (United States)

    Gedney, Stephen D.; Whites, Keith W.

    1994-10-01

    Army Research Office Grant #DAAH04-93-G-0453 has supported the purchase of 24 additional compute nodes that were installed in the Intel iPsC/860 hypercube at the Univesity Of Kentucky (UK), rendering a 32-node multiprocessor. This facility has allowed the investigators to explore and extend the boundaries of electromagnetic simulation for important areas of defense concerns including microwave monolithic integrated circuit (MMIC) design/analysis and electromagnetic materials research and development. The iPSC/860 has also provided an ideal platform for MMIC circuit simulations. A number of parallel methods based on direct time-domain solutions of Maxwell's equations have been developed on the iPSC/860, including a parallel finite-difference time-domain (FDTD) algorithm, and a parallel planar generalized Yee-algorithm (PGY). The iPSC/860 has also provided an ideal platform on which to develop a 'virtual laboratory' to numerically analyze, scientifically study and develop new types of materials with beneficial electromagnetic properties. These materials simulations are capable of assembling hundreds of microscopic inclusions from which an electromagnetic full-wave solution will be obtained in toto. This powerful simulation tool has enabled research of the full-wave analysis of complex multicomponent MMIC devices and the electromagnetic properties of many types of materials to be performed numerically rather than strictly in the laboratory.

  16. Driving Simulator Development and Performance Study

    OpenAIRE

    Juto, Erik

    2010-01-01

    The driving simulator is a vital tool for much of the research performed at theSwedish National Road and Transport Institute (VTI). Currently VTI posses three driving simulators, two high fidelity simulators developed and constructed by VTI, and a medium fidelity simulator from the German company Dr.-Ing. Reiner Foerst GmbH. The two high fidelity simulators run the same simulation software, developed at VTI. The medium fidelity simulator runs a proprietary simulation software. At VTI there is...

  17. Microlearning mApp raises health competence: hybrid service design.

    Science.gov (United States)

    Simons, Luuk P A; Foerster, Florian; Bruck, Peter A; Motiwalla, Luvai; Jonker, Catholijn M

    Work place health support interventions can help support our aging work force, with mApps offering cost-effectiveness opportunities. Previous research shows that health support apps should offer users enough newness and relevance each time they are used. Otherwise the 'eHealth law of attrition' applies: 90 % of users are lost prematurely. Our research study builds on this prior research with further investigation on whether a mobile health quiz provides added value for users within a hybrid service mix and whether it promotes long term health? We developed a hybrid health support intervention solution that uses a mix of electronic and physical support services for improving health behaviours, including a mobile micro-learning health quiz. This solution was evaluated in a multiple-case study at three work sites with 86 users. We find that both our mobile health quiz and the overall hybrid solution contributed to improvements in health readiness, -behaviour and -competence. Users indicated that the micro-learning health quiz courses provided new and relevant information. Relatively high utilization rates of the health quiz were observed. Participants indicated that health insights were given that directly influenced every day health perceptions, -choices, coping and goal achievement strategies, plus motivation and self-norms. This points to increased user health self-management competence. Moreover, even after 10 months they indicated to still have improved health awareness, -motivation and -behaviours (food, physical activity, mental recuperation). A design analysis was conducted regarding service mix efficacy; the mobile micro-learning health quiz helped fulfil a set of key requirements that exist for designing ICT-enabled lifestyle interventions, largely in the way it was anticipated.

  18. GenMAPP 2: new features and resources for pathway analysis

    Directory of Open Access Journals (Sweden)

    Dahlquist Kam D

    2007-06-01

    Full Text Available Abstract Background Microarray technologies have evolved rapidly, enabling biologists to quantify genome-wide levels of gene expression, alternative splicing, and sequence variations for a variety of species. Analyzing and displaying these data present a significant challenge. Pathway-based approaches for analyzing microarray data have proven useful for presenting data and for generating testable hypotheses. Results To address the growing needs of the microarray community we have released version 2 of Gene Map Annotator and Pathway Profiler (GenMAPP, a new GenMAPP database schema, and integrated resources for pathway analysis. We have redesigned the GenMAPP database to support multiple gene annotations and species as well as custom species database creation for a potentially unlimited number of species. We have expanded our pathway resources by utilizing homology information to translate pathway content between species and extending existing pathways with data derived from conserved protein interactions and coexpression. We have implemented a new mode of data visualization to support analysis of complex data, including time-course, single nucleotide polymorphism (SNP, and splicing. GenMAPP version 2 also offers innovative ways to display and share data by incorporating HTML export of analyses for entire sets of pathways as organized web pages. Conclusion GenMAPP version 2 provides a means to rapidly interrogate complex experimental data for pathway-level changes in a diverse range of organisms.

  19. Crowdsourcing as citizen-empowered tool for natural hazards. The MAppERS project.

    Science.gov (United States)

    Bossi, Giulia; Mantovani, Matteo; Frigerio, Simone; Møller Janniche, Amalie; Bianchizza, Chiara; Del Bianco, Daniele

    2016-04-01

    MAppERS is a co-financed project by European Commission and it is focused on natural hazards risk prevention and emergency response, through the development of a smartphone application. The idea relies on the role of citizens and volunteers as 'territorial mappers' and the information they can provide to civil protection operators through the use of their smartphones. The strategy is to promote the active participation of citizens and volunteers in disaster risk reduction promoting responsibility and preparedness. The application embraces tools for crowdsourcing data collection, for preparedness, prevention and alert warnings. The pilot activity conducted in order to assess its usability and performance is presented. One activity presented took place in Denmark, by Frederikssund Halsnæs Fire & Rescue Service, where 12 voluntary citizens were enrolled. The age ranged between young and elderly people with different educational level. Two separated groups were defined; one followed an introductory course on the application usage and were supervised during the test, while the other was untrained and without support. The usability of the app was assessed through the filling in of a form. Results showed that volunteers were extremely interested in the app and were seeing the advantage of using it. The app was considered user-friendly even to elderly people. The differences in comprehension of several aspects of the application by the two groups allowed to highlight the weak points in terms of approachability. These were then addressed in the following release of the app.

  20. Aircraft Performance for Open Air Traffic Simulations

    NARCIS (Netherlands)

    Metz, I.C.; Hoekstra, J.M.; Ellerbroek, J.; Kugler, D.

    2016-01-01

    The BlueSky Open Air Tra_c Simulator developed by the Control & Simulation section of TU Delft aims at supporting research for analysing Air Tra_c Management concepts by providing an open source simulation platform. The goal of this study was to complement BlueSky with aircraft performance

  1. Photovoltaic array performance simulation models

    Energy Technology Data Exchange (ETDEWEB)

    Menicucci, D. F.

    1986-09-15

    The experience of the solar industry confirms that, despite recent cost reductions, the profitability of photovoltaic (PV) systems is often marginal and the configuration and sizing of a system is a critical problem for the design engineer. Construction and evaluation of experimental systems are expensive and seldom justifiable. A mathematical model or computer-simulation program is a desirable alternative, provided reliable results can be obtained. Sandia National Laboratories, Albuquerque (SNLA), has been studying PV-system modeling techniques in an effort to develop an effective tool to be used by engineers and architects in the design of cost-effective PV systems. This paper reviews two of the sources of error found in previous PV modeling programs, presents the remedies developed to correct these errors, and describes a new program that incorporates these improvements.

  2. Key performance indicators for successful simulation projects

    OpenAIRE

    Jahangirian, M; Taylor, SJE; Young, T; Robinson, S

    2016-01-01

    There are many factors that may contribute to the successful delivery of a simulation project. To provide a structured approach to assessing the impact various factors have on project success, we propose a top-down framework whereby 15 Key Performance Indicators (KPI) are developed that represent the level of successfulness of simulation projects from various perspectives. They are linked to a set of Critical Success Factors (CSF) as reported in the simulation literature. A single measure cal...

  3. SLC positron source: Simulation and performance

    International Nuclear Information System (INIS)

    Pitthan, R.; Braun, H.; Clendenin, J.E.; Ecklund, S.D.; Helm, R.H.; Kulikov, A.V.; Odian, A.C.; Pei, G.X.; Ross, M.C.; Woodley, M.D.

    1991-06-01

    Performance of the source was found to be in good general agreement with computer simulations with S-band acceleration, and where not, the simulations lead to identification of problems, in particular the underestimated impact of linac misalignments due to the 1989 Loma Prieta Earthquake. 13 refs., 7 figs

  4. Team Culture and Business Strategy Simulation Performance

    Science.gov (United States)

    Ritchie, William J.; Fornaciari, Charles J.; Drew, Stephen A. W.; Marlin, Dan

    2013-01-01

    Many capstone strategic management courses use computer-based simulations as core pedagogical tools. Simulations are touted as assisting students in developing much-valued skills in strategy formation, implementation, and team management in the pursuit of superior strategic performance. However, despite their rich nature, little is known regarding…

  5. Building performance simulation for sustainable buildings

    NARCIS (Netherlands)

    Hensen, J.L.M.

    2010-01-01

    This paper aims to provide a general view of the background and current state of building performance simulation, which has the potential to deliver, directly or indirectly, substantial benefits to building stakeholders and to the environment. However the building simulation community faces many

  6. Flight Tasks and Metrics to Evaluate Laser Eye Protection in Flight Simulators

    Science.gov (United States)

    2017-07-07

    IFR ) IFR Instrument Flight Rules LED Light Emitting Diode LEP Laser Eye Protection MAPP Model Assessing Pilot Performance OD Optical Density...LEP and then use them to assess the impact of wearing LEP in a flight simulator environment. 2 Pending Distribution, A: Approved for public...2005). LEP has the potential to alter distinct characteristics of the visual environment, giving rise to concerns over the impact on flight tasks and

  7. Simulating Performance Risk for Lighting Retrofit Decisions

    Directory of Open Access Journals (Sweden)

    Jia Hu

    2015-05-01

    Full Text Available In building retrofit projects, dynamic simulations are performed to simulate building performance. Uncertainty may negatively affect model calibration and predicted lighting energy savings, which increases the chance of default on performance-based contracts. Therefore, the aim of this paper is to develop a simulation-based method that can analyze lighting performance risk in lighting retrofit decisions. The model uses a surrogate model, which is constructed by adaptively selecting sample points and generating approximation surfaces with fast computing time. The surrogate model is a replacement of the computation intensive process. A statistical method is developed to generate extreme weather profile based on the 20-year historical weather data. A stochastic occupancy model was created using actual occupancy data to generate realistic occupancy patterns. Energy usage of lighting, and heating, ventilation, and air conditioning (HVAC is simulated using EnergyPlus. The method can evaluate the influence of different risk factors (e.g., variation of luminaire input wattage, varying weather conditions on lighting and HVAC energy consumption and lighting electricity demand. Probability distributions are generated to quantify the risk values. A case study was conducted to demonstrate and validate the methods. The surrogate model is a good solution for quantifying the risk factors and probability distribution of the building performance.

  8. Performance Optimization of the ATLAS Detector Simulation

    CERN Document Server

    AUTHOR|(CDS)2091018

    In the thesis at hand the current performance of the ATLAS detector simulation, part of the Athena framework, is analyzed and possible optimizations are examined. For this purpose the event based sampling profiler VTune Amplifier by Intel is utilized. As the most important metric to measure improvements, the total execution time of the simulation of $t\\bar{t}$ events is also considered. All efforts are focused on structural changes, which do not influence the simulation output and can be attributed to CPU specific issues, especially front end stalls and vectorization. The most promising change is the activation of profile guided optimization for Geant4, which is a critical external dependency of the simulation. Profile guided optimization gives an average improvement of $8.9\\%$ and $10.0\\%$ for the two considered cases at the cost of one additional compilation (instrumented binaries) and execution (training to obtain profiling data) at build time.

  9. Approaching Sentient Building Performance Simulation Systems

    DEFF Research Database (Denmark)

    Negendahl, Kristoffer; Perkov, Thomas; Heller, Alfred

    2014-01-01

    Sentient BPS systems can combine one or more high precision BPS and provide near instantaneous performance feedback directly in the design tool, thus providing speed and precision of building performance in the early design stages. Sentient BPS systems are essentially combining: 1) design tools, 2......) parametric tools, 3) BPS tools, 4) dynamic databases 5) interpolation techniques and 6) prediction techniques as a fast and valid simulation system, in the early design stage....

  10. Behaviour of concrete nuclear containment structures upto ultimate failure with special reference to MAPP-1 containment

    International Nuclear Information System (INIS)

    Appa Rao, T.V.S.R.

    1975-01-01

    Theoretical and experimental methods for investigating the behaviour of concrete secondary containment structures subjected to loads upto their ultimate failure have been discussed in the paper. Need for inelastic nonlinear analysis of containments has been emphasized. Different contitutive models of concrete that can be employed in the nonlinear analysis of concrete structures were briefly reviewed. Based on the experimental results obtained in a 1:12 scale model test conducted at the Structural Engineering Research (Regional) Centre, Madras, behaviour of the MAPP-1 containment to internal pressure loading upto its ultimate failure has been discussed. (author)

  11. Simulating and stimulating performance: Introducing distributed simulation to enhance musical learning and performance

    Directory of Open Access Journals (Sweden)

    Aaron eWilliamon

    2014-02-01

    Full Text Available Musicians typically rehearse far away from their audiences and in practice rooms that differ significantly from the concert venues in which they aspire to perform. Due to the high costs and inaccessibility of such venues, much current international music training lacks repeated exposure to realistic performance situations, with students learning all too late (or not at all how to manage performance stress and the demands of their audiences. Virtual environments have been shown to be an effective training tool in the fields of medicine and sport, offering practitioners access to real-life performance scenarios but with lower risk of negative evaluation and outcomes. The aim of this research was to design and test the efficacy of simulated performance environments in which conditions of real performance could be recreated. Advanced violin students (n=11 were recruited to perform in two simulations: a solo recital with a small virtual audience and an audition situation with three expert virtual judges. Each simulation contained back-stage and on-stage areas, life-sized interactive virtual observers, and pre- and post-performance protocols designed to match those found at leading international performance venues. Participants completed a questionnaire on their experiences of using the simulations. Results show that both simulated environments offered realistic experience of performance contexts and were rated particularly useful for developing performance skills. For a subset of 7 violinists, state anxiety and electrocardiographic data were collected during the simulated audition and an actual audition with real judges. Results display comparable levels of reported state anxiety and patterns of heart rate variability in both situations, suggesting that responses to the simulated audition closely approximate those of a real audition. The findings are discussed in relation to their implications, both generalizable and individual-specific, for

  12. Simulating and stimulating performance: introducing distributed simulation to enhance musical learning and performance.

    Science.gov (United States)

    Williamon, Aaron; Aufegger, Lisa; Eiholzer, Hubert

    2014-01-01

    Musicians typically rehearse far away from their audiences and in practice rooms that differ significantly from the concert venues in which they aspire to perform. Due to the high costs and inaccessibility of such venues, much current international music training lacks repeated exposure to realistic performance situations, with students learning all too late (or not at all) how to manage performance stress and the demands of their audiences. Virtual environments have been shown to be an effective training tool in the fields of medicine and sport, offering practitioners access to real-life performance scenarios but with lower risk of negative evaluation and outcomes. The aim of this research was to design and test the efficacy of simulated performance environments in which conditions of "real" performance could be recreated. Advanced violin students (n = 11) were recruited to perform in two simulations: a solo recital with a small virtual audience and an audition situation with three "expert" virtual judges. Each simulation contained back-stage and on-stage areas, life-sized interactive virtual observers, and pre- and post-performance protocols designed to match those found at leading international performance venues. Participants completed a questionnaire on their experiences of using the simulations. Results show that both simulated environments offered realistic experience of performance contexts and were rated particularly useful for developing performance skills. For a subset of 7 violinists, state anxiety and electrocardiographic data were collected during the simulated audition and an actual audition with real judges. Results display comparable levels of reported state anxiety and patterns of heart rate variability in both situations, suggesting that responses to the simulated audition closely approximate those of a real audition. The findings are discussed in relation to their implications, both generalizable and individual-specific, for performance training.

  13. Multisite, multimodal neuroimaging of chronic urological pelvic pain: Methodology of the MAPP Research Network

    Directory of Open Access Journals (Sweden)

    Jeffry R. Alger

    2016-01-01

    Full Text Available The Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP Research Network is an ongoing multi-center collaborative research group established to conduct integrated studies in participants with urologic chronic pelvic pain syndrome (UCPPS. The goal of these investigations is to provide new insights into the etiology, natural history, clinical, demographic and behavioral characteristics, search for new and evaluate candidate biomarkers, systematically test for contributions of infectious agents to symptoms, and conduct animal studies to understand underlying mechanisms for UCPPS. Study participants were enrolled in a one-year observational study and evaluated through a multisite, collaborative neuroimaging study to evaluate the association between UCPPS and brain structure and function. 3D T1-weighted structural images, resting-state fMRI, and high angular resolution diffusion MRI were acquired in five participating MAPP Network sites using 8 separate MRI hardware and software configurations. We describe the neuroimaging methods and procedures used to scan participants, the challenges encountered in obtaining data from multiple sites with different equipment/software, and our efforts to minimize site-to-site variation.

  14. CASTOR detector. Model, objectives and simulated performance

    International Nuclear Information System (INIS)

    Angelis, A. L. S.; Mavromanolakis, G.; Panagiotou, A. D.; Aslanoglou, X.; Nicolis, N.; Lobanov, M.; Erine, S.; Kharlov, Y. V.; Bogolyubsky, M. Y.; Kurepin, A. B.; Chileev, K.; Wlodarczyk, Z.

    2001-01-01

    It is presented a phenomenological model describing the formation and evolution of a Centauro fireball in the baryon-rich region in nucleus-nucleus interactions in the upper atmosphere and at the LHC. The small particle multiplicity and imbalance of electromagnetic and hadronic content characterizing a Centauro event and also the strongly penetrating particles (assumed to be strangelets) frequently accompanying them can be naturally explained. It is described the CASTOR calorimeter, a sub detector of the ALICE experiment dedicated to the search for Centauro in the very forward, baryon-rich region of central Pb+Pb collisions at the LHC. The basic characteristics and simulated performance of the calorimeter are presented

  15. Problem reporting management system performance simulation

    Science.gov (United States)

    Vannatta, David S.

    1993-01-01

    This paper proposes the Problem Reporting Management System (PRMS) model as an effective discrete simulation tool that determines the risks involved during the development phase of a Trouble Tracking Reporting Data Base replacement system. The model considers the type of equipment and networks which will be used in the replacement system as well as varying user loads, size of the database, and expected operational availability. The paper discusses the dynamics, stability, and application of the PRMS and addresses suggested concepts to enhance the service performance and enrich them.

  16. The COD Model: Simulating Workgroup Performance

    Science.gov (United States)

    Biggiero, Lucio; Sevi, Enrico

    Though the question of the determinants of workgroup performance is one of the most central in organization science, precise theoretical frameworks and formal demonstrations are still missing. In order to fill in this gap the COD agent-based simulation model is here presented and used to study the effects of task interdependence and bounded rationality on workgroup performance. The first relevant finding is an algorithmic demonstration of the ordering of interdependencies in terms of complexity, showing that the parallel mode is the most simplex, followed by the sequential and then by the reciprocal. This result is far from being new in organization science, but what is remarkable is that now it has the strength of an algorithmic demonstration instead of being based on the authoritativeness of some scholar or on some episodic empirical finding. The second important result is that the progressive introduction of realistic limits to agents' rationality dramatically reduces workgroup performance and addresses to a rather interesting result: when agents' rationality is severely bounded simple norms work better than complex norms. The third main finding is that when the complexity of interdependence is high, then the appropriate coordination mechanism is agents' direct and active collaboration, which means teamwork.

  17. Human Performance in Simulated Reduced Gravity Environments

    Science.gov (United States)

    Cowley, Matthew; Harvill, Lauren; Rajulu, Sudhakar

    2014-01-01

    NASA is currently designing a new space suit capable of working in deep space and on Mars. Designing a suit is very difficult and often requires trade-offs between performance, cost, mass, and system complexity. Our current understanding of human performance in reduced gravity in a planetary environment (the moon or Mars) is limited to lunar observations, studies from the Apollo program, and recent suit tests conducted at JSC using reduced gravity simulators. This study will look at our most recent reduced gravity simulations performed on the new Active Response Gravity Offload System (ARGOS) compared to the C-9 reduced gravity plane. Methods: Subjects ambulated in reduced gravity analogs to obtain a baseline for human performance. Subjects were tested in lunar gravity (1.6 m/sq s) and Earth gravity (9.8 m/sq s) in shirt-sleeves. Subjects ambulated over ground at prescribed speeds on the ARGOS, but ambulated at a self-selected speed on the C-9 due to time limitations. Subjects on the ARGOS were given over 3 minutes to acclimate to the different conditions before data was collected. Nine healthy subjects were tested in the ARGOS (6 males, 3 females, 79.5 +/- 15.7 kg), while six subjects were tested on the C-9 (6 males, 78.8 +/- 11.2 kg). Data was collected with an optical motion capture system (Vicon, Oxford, UK) and was analyzed using customized analysis scripts in BodyBuilder (Vicon, Oxford, UK) and MATLAB (MathWorks, Natick, MA, USA). Results: In all offloaded conditions, variation between subjects increased compared to 1-g. Kinematics in the ARGOS at lunar gravity resembled earth gravity ambulation more closely than the C-9 ambulation. Toe-off occurred 10% earlier in both reduced gravity environments compared to earth gravity, shortening the stance phase. Likewise, ankle, knee, and hip angles remained consistently flexed and had reduced peaks compared to earth gravity. Ground reaction forces in lunar gravity (normalized to Earth body weight) were 0.4 +/- 0.2 on

  18. MAppERS: a peer-produced community for emergency support

    Science.gov (United States)

    Frigerio, Simone; Schenato, Luca; Bianchizza, Chiara; Del Bianco, Daniele

    2014-05-01

    A general trend in European governance tends to shift responsibilities in territorial management from national central authorities to local/regional levels and to the citizens as first actors of Civil Protection. Prevention is a long term goal that rests not only on the capacities of professional operators and volunteers, but that has to necessarily imply the involvement and awareness of the citizens over the territory they inhabit. In fact people often do not have chance to interact in the surveillance of the territory and only face risks when they have to bear impacts on their lives. Involvement of population creates more cost-effective and context-specific strategies of territorial surveillance and management. A collaborative user environment is useful for emergency response and support in the wake of disasters, feeding updated information on the ground directly to on-site responders. MAppERS (Mobile Application for Emergency Response and Support) is a EU project (funded under programme 2013-2015 Humanitarian Aid and Civil Protection, ECHO A5) which empowers citizens as "crowd-sourced mappers" through the development of a smart phone application able to collect GPS-localised and detailed parameters, that can then be sent from citizens to civil protection operators in a contest of geospatial response. The process of app design includes feedback from citizens, involving them in training courses on the monitoring of the territory as long term objective of raising public awareness and participation from the citizens, as actors in a networked disaster response community. The project proceeds from the design and testing of the smart phone applications (module MAppERS-V for volunteers, module MAppERS-C for citizens) according to software engineering environment (Android and Iphone SDK). Information exchange and data transfer need clearness and efficiency; thus a previous research is conducted on the cost-effectiveness of already existing practices for territorial

  19. High-Performance Beam Simulator for the LANSCE Linac

    International Nuclear Information System (INIS)

    Pang, Xiaoying; Rybarcyk, Lawrence J.; Baily, Scott A.

    2012-01-01

    A high performance multiparticle tracking simulator is currently under development at Los Alamos. The heart of the simulator is based upon the beam dynamics simulation algorithms of the PARMILA code, but implemented in C++ on Graphics Processing Unit (GPU) hardware using NVIDIA's CUDA platform. Linac operating set points are provided to the simulator via the EPICS control system so that changes of the real time linac parameters are tracked and the simulation results updated automatically. This simulator will provide valuable insight into the beam dynamics along a linac in pseudo real-time, especially where direct measurements of the beam properties do not exist. Details regarding the approach, benefits and performance are presented.

  20. Equivalent drawbead performance in deep drawing simulations

    NARCIS (Netherlands)

    Meinders, Vincent T.; Geijselaers, Hubertus J.M.; Huetink, Han

    1999-01-01

    Drawbeads are applied in the deep drawing process to improve the control of the material flow during the forming operation. In simulations of the deep drawing process these drawbeads can be replaced by an equivalent drawbead model. In this paper the usage of an equivalent drawbead model in the

  1. MAppERS experience: natural processes and preparedness in the societal context

    Science.gov (United States)

    Frigerio, Simone; Schenato, Luca; Bossi, Giulia; Mantovani, Matteo; Marcato, Gianluca; Pasuto, Alessandro

    2016-04-01

    Within natural processes responsibilities from central authorities to local levels as first actors of civil protection is a changing pattern. Prevention and preparedness in natural hazards are long-term goals based on capacities of professional volunteers, and improving the awareness of the citizens as local inhabitants. Local people have impacts on their lives but training and involvement towards specific techniques change their role within risk communication and emergency preparedness. A collaborative user environment is useful for emergency response and support in the wake of disasters, feeding updated information on the ground directly to on-site responders. MAppERS (Mobile Application for Emergency Response and Support) is a funded project (2013-2015 Humanitarian Aid and Civil Protection, ECHO A5) based on human role as "crowd-sourced mappers" through smart phone application able to share GPS-localised and detailed parameters. The feedback from testing and the training courses aim to raising public awareness and participation in a networked disaster response. The project implies design and test of smart phone linked with a real-time dashboard platform for rescue services citizens and volunteers of civil protection. Two pilot sites, including trainings on modules functioning control usability and quality of the product. The synchronized platform offers the activity of cloud data collection with a central data dashboard. Information is collected in a context of floods processes, with crowdsourcing action from local population, for proper awareness with own personal flood plan and long-term preparedness. A second context tested pre-emergency actions on field with rescue team, collecting state-of-art and condition of hazards.

  2. Manufacturing plant performance evaluation by discrete event simulation

    International Nuclear Information System (INIS)

    Rosli Darmawan; Mohd Rasid Osman; Rosnah Mohd Yusuff; Napsiah Ismail; Zulkiflie Leman

    2002-01-01

    A case study was conducted to evaluate the performance of a manufacturing plant using discrete event simulation technique. The study was carried out on animal feed production plant. Sterifeed plant at Malaysian Institute for Nuclear Technology Research (MINT), Selangor, Malaysia. The plant was modelled base on the actual manufacturing activities recorded by the operators. The simulation was carried out using a discrete event simulation software. The model was validated by comparing the simulation results with the actual operational data of the plant. The simulation results show some weaknesses with the current plant design and proposals were made to improve the plant performance. (Author)

  3. Modelling and simulating fire tube boiler performance

    DEFF Research Database (Denmark)

    Sørensen, K.; Condra, T.; Houbak, Niels

    2003-01-01

    A model for a flue gas boiler covering the flue gas and the water-/steam side has been formulated. The model has been formulated as a number of sub models that are merged into an overall model for the complete boiler. Sub models have been defined for the furnace, the convection zone (split in 2......: a zone submerged in water and a zone covered by steam), a model for the material in the boiler (the steel) and 2 models for resp. the water/steam zone (the boiling) and the steam. The dynamic model has been developed as a number of Differential-Algebraic-Equation system (DAE). Subsequently Mat......Lab/Simulink has been applied for carrying out the simulations. To be able to verify the simulated results experiments has been carried out on a full scale boiler plant....

  4. Simulating Radar Signals for Detection Performance Evaluation.

    Science.gov (United States)

    1981-02-01

    incurring the computation costs usually as- sociated with such simulations. With importance sampling one can modify the probability distribution of the...049.7 0110 IF (N0147-1) ?0Q,7oG.6oSi V4.48 102 61 IrF?=TFACTUIFI*VF1 O. All THryAV.THrTA 1S A I~ THF’r P THF T r/LCAT I IVF /’NF 1204!! %S1PP7FS(T4rTAW

  5. Improving the Performance of the Extreme-scale Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Engelmann, Christian [ORNL; Naughton III, Thomas J [ORNL

    2014-01-01

    Investigating the performance of parallel applications at scale on future high-performance computing (HPC) architectures and the performance impact of different architecture choices is an important component of HPC hardware/software co-design. The Extreme-scale Simulator (xSim) is a simulation-based toolkit for investigating the performance of parallel applications at scale. xSim scales to millions of simulated Message Passing Interface (MPI) processes. The overhead introduced by a simulation tool is an important performance and productivity aspect. This paper documents two improvements to xSim: (1) a new deadlock resolution protocol to reduce the parallel discrete event simulation management overhead and (2) a new simulated MPI message matching algorithm to reduce the oversubscription management overhead. The results clearly show a significant performance improvement, such as by reducing the simulation overhead for running the NAS Parallel Benchmark suite inside the simulator from 1,020\\% to 238% for the conjugate gradient (CG) benchmark and from 102% to 0% for the embarrassingly parallel (EP) and benchmark, as well as, from 37,511% to 13,808% for CG and from 3,332% to 204% for EP with accurate process failure simulation.

  6. SEAscan 3.5: A simulator performance analyzer

    International Nuclear Information System (INIS)

    Dennis, T.; Eisenmann, S.

    1990-01-01

    SEAscan 3.5 is a personal computer based tool developed to analyze the dynamic performance of nuclear power plant training simulators. The system has integrated features to provide its own human featured performance. In this paper, the program is described as a tool for the analysis of training simulator performance. The structure and operating characteristics of SEAscan 3.5 are described. The hardcopy documents are shown to aid in verification of conformance to ANSI/ANS-3.5-1985

  7. Artificial neural network simulation of battery performance

    Energy Technology Data Exchange (ETDEWEB)

    O`Gorman, C.C.; Ingersoll, D.; Jungst, R.G.; Paez, T.L.

    1998-12-31

    Although they appear deceptively simple, batteries embody a complex set of interacting physical and chemical processes. While the discrete engineering characteristics of a battery such as the physical dimensions of the individual components, are relatively straightforward to define explicitly, their myriad chemical and physical processes, including interactions, are much more difficult to accurately represent. Within this category are the diffusive and solubility characteristics of individual species, reaction kinetics and mechanisms of primary chemical species as well as intermediates, and growth and morphology characteristics of reaction products as influenced by environmental and operational use profiles. For this reason, development of analytical models that can consistently predict the performance of a battery has only been partially successful, even though significant resources have been applied to this problem. As an alternative approach, the authors have begun development of a non-phenomenological model for battery systems based on artificial neural networks. Both recurrent and non-recurrent forms of these networks have been successfully used to develop accurate representations of battery behavior. The connectionist normalized linear spline (CMLS) network has been implemented with a self-organizing layer to model a battery system with the generalized radial basis function net. Concurrently, efforts are under way to use the feedforward back propagation network to map the {open_quotes}state{close_quotes} of a battery system. Because of the complexity of battery systems, accurate representation of the input and output parameters has proven to be very important. This paper describes these initial feasibility studies as well as the current models and makes comparisons between predicted and actual performance.

  8. Comparison of performance of simulation models for floor heating

    DEFF Research Database (Denmark)

    Weitzmann, Peter; Svendsen, Svend

    2005-01-01

    This paper describes the comparison of performance of simulation models for floor heating with different level of detail in the modelling process. The models are compared in an otherwise identical simulation model containing room model, walls, windows, ceiling and ventilation system. By exchanging...

  9. Building Performance Simulation for Sustainable Energy Use in Buildings

    NARCIS (Netherlands)

    Hensen, J.L.M.

    2010-01-01

    This paper aims to provide a general view of the background and current state of building performance simulation, which has the potential to deliver, directly or indirectly, substantial benefits to building stakeholders and to the environment. However the building simulation community faces many

  10. Building performance simulation for sustainable building design and operation

    NARCIS (Netherlands)

    Hensen, J.L.M.

    2011-01-01

    This paper aims to provide a general view of the background and current state of building performance simulation, which has the potential to deliver, directly or indirectly, substantial benefits to building stakeholders and to the environment. However the building simulation community faces many

  11. Patients' perspectives in the management of psoriasis: the Italian results of the Multinational Assessment of Psoriasis and Psoriatic Arthritis (MAPP) survey.

    Science.gov (United States)

    Gisondi, Paolo; Girolomoni, Giampiero

    2017-08-01

    The perspective of patients with psoriasis about medical care treatment goals and strategies is receiving increasing attention. Here, we performed a country-based analysis of the Multinational Assessment of Psoriasis and Psoriatic Arthritis (MAPP) survey, in order to provide specific information on patients' perspective of treatment of psoriasis in Italy. This was a systematic household telephone survey recruiting subjects by random digit dialing. Household members ≥18 years were included if they had ever been diagnosed with psoriasis. About 12,785 households were screened in Italy. 132 patients were ineligible for the analysis, including patients with psoriatic arthritis. 359 patients were surveyed. About half of the patients had very mild disease with less than 1 palm skin involvement, and 38% had 1-10 palm skin disease. It is noteworthy that 48% of patients with widespread disease were not taking any medication. Patients indicated the relief of symptoms, including itching (54.9%), as the main goal for their current therapy, whereas 14.2% reported no specific expectation from their medication. Overall, 70% of patients declared to be satisfied by their therapy, in terms of primary goal reached. Our findings suggest that most psoriasis patients have mild/moderate disease in Italy, and that a portion of patients with severe disease does not receive an adequate treatment.

  12. Alcohol consumption for simulated driving performance: A systematic review

    Directory of Open Access Journals (Sweden)

    Mohammad Saeid Rezaee-Zavareh

    2017-06-01

    Conclusion: Alcohol consumption may decrease simulated driving performance in alcohol consumed people compared with non-alcohol consumed people via changes in SDSD, LPSD, speed, MLPD, LC and NA. More well-designed randomized controlled clinical trials are recommended.

  13. 20th Joint Workshop on Sustained Simulation Performance

    CERN Document Server

    Bez, Wolfgang; Focht, Erich; Patel, Nisarg; Kobayashi, Hiroaki

    2016-01-01

    The book presents the state of the art in high-performance computing and simulation on modern supercomputer architectures. It explores general trends in hardware and software development, and then focuses specifically on the future of high-performance systems and heterogeneous architectures. It also covers applications such as computational fluid dynamics, material science, medical applications and climate research and discusses innovative fields like coupled multi-physics or multi-scale simulations. The papers included were selected from the presentations given at the 20th Workshop on Sustained Simulation Performance at the HLRS, University of Stuttgart, Germany in December 2015, and the subsequent Workshop on Sustained Simulation Performance at Tohoku University in February 2016.

  14. 24th & 25th Joint Workshop on Sustained Simulation Performance

    CERN Document Server

    Bez, Wolfgang; Focht, Erich; Gienger, Michael; Kobayashi, Hiroaki

    2017-01-01

    This book presents the state of the art in High Performance Computing on modern supercomputer architectures. It addresses trends in hardware and software development in general, as well as the future of High Performance Computing systems and heterogeneous architectures. The contributions cover a broad range of topics, from improved system management to Computational Fluid Dynamics, High Performance Data Analytics, and novel mathematical approaches for large-scale systems. In addition, they explore innovative fields like coupled multi-physics and multi-scale simulations. All contributions are based on selected papers presented at the 24th Workshop on Sustained Simulation Performance, held at the University of Stuttgart’s High Performance Computing Center in Stuttgart, Germany in December 2016 and the subsequent Workshop on Sustained Simulation Performance, held at the Cyberscience Center, Tohoku University, Japan in March 2017.

  15. Simulation and performance of brushless DC motor actuators

    OpenAIRE

    Gerba, Alex

    1985-01-01

    The simulation model for a Brushless D.C. Motor and the associated commutation power conditioner transistor model are presented. The necessary conditions for maximum power output while operating at steady-state speed and sinusoidally distributed air-gap flux are developed. Comparisons of simulated model with the measured performance of a typical motor are done both on time response waveforms and on average performance characteristics. These preliminary results indicate good ...

  16. Simultaneous polarimeter retrievals of microphysical aerosol and ocean color parameters from the "MAPP" algorithm with comparison to high-spectral-resolution lidar aerosol and ocean products.

    Science.gov (United States)

    Stamnes, S; Hostetler, C; Ferrare, R; Burton, S; Liu, X; Hair, J; Hu, Y; Wasilewski, A; Martin, W; van Diedenhoven, B; Chowdhary, J; Cetinić, I; Berg, L K; Stamnes, K; Cairns, B

    2018-04-01

    We present an optimal-estimation-based retrieval framework, the microphysical aerosol properties from polarimetry (MAPP) algorithm, designed for simultaneous retrieval of aerosol microphysical properties and ocean color bio-optical parameters using multi-angular total and polarized radiances. Polarimetric measurements from the airborne NASA Research Scanning Polarimeter (RSP) were inverted by MAPP to produce atmosphere and ocean products. The RSP MAPP results are compared with co-incident lidar measurements made by the NASA High-Spectral-Resolution Lidar HSRL-1 and HSRL-2 instruments. Comparisons are made of the aerosol optical depth (AOD) at 355 and 532 nm, lidar column-averaged measurements of the aerosol lidar ratio and Ångstrøm exponent, and lidar ocean measurements of the particulate hemispherical backscatter coefficient and the diffuse attenuation coefficient. The measurements were collected during the 2012 Two-Column Aerosol Project (TCAP) campaign and the 2014 Ship-Aircraft Bio-Optical Research (SABOR) campaign. For the SABOR campaign, 73% RSP MAPP retrievals fall within ±0.04 AOD at 532 nm as measured by HSRL-1, with an R value of 0.933 and root-mean-square deviation of 0.0372. For the TCAP campaign, 53% of RSP MAPP retrievals are within 0.04 AOD as measured by HSRL-2, with an R value of 0.927 and root-mean-square deviation of 0.0673. Comparisons with HSRL-2 AOD at 355 nm during TCAP result in an R value of 0.959 and a root-mean-square deviation of 0.0694. The RSP retrievals using the MAPP optimal estimation framework represent a key milestone on the path to a combined lidar + polarimeter retrieval using both HSRL and RSP measurements.

  17. A Simulation Approach for Performance Validation during Embedded Systems Design

    Science.gov (United States)

    Wang, Zhonglei; Haberl, Wolfgang; Herkersdorf, Andreas; Wechs, Martin

    Due to the time-to-market pressure, it is highly desirable to design hardware and software of embedded systems in parallel. However, hardware and software are developed mostly using very different methods, so that performance evaluation and validation of the whole system is not an easy task. In this paper, we propose a simulation approach to bridge the gap between model-driven software development and simulation based hardware design, by merging hardware and software models into a SystemC based simulation environment. An automated procedure has been established to generate software simulation models from formal models, while the hardware design is originally modeled in SystemC. As the simulation models are annotated with timing information, performance issues are tackled in the same pass as system functionality, rather than in a dedicated approach.

  18. Improving the performance of a filling line based on simulation

    Science.gov (United States)

    Jasiulewicz-Kaczmarek, M.; Bartkowiak, T.

    2016-08-01

    The paper describes the method of improving performance of a filling line based on simulation. This study concerns a production line that is located in a manufacturing centre of a FMCG company. A discrete event simulation model was built using data provided by maintenance data acquisition system. Two types of failures were identified in the system and were approximated using continuous statistical distributions. The model was validated taking into consideration line performance measures. A brief Pareto analysis of line failures was conducted to identify potential areas of improvement. Two improvements scenarios were proposed and tested via simulation. The outcome of the simulations were the bases of financial analysis. NPV and ROI values were calculated taking into account depreciation, profits, losses, current CIT rate and inflation. A validated simulation model can be a useful tool in maintenance decision-making process.

  19. Relating Standardized Visual Perception Measures to Simulator Visual System Performance

    Science.gov (United States)

    Kaiser, Mary K.; Sweet, Barbara T.

    2013-01-01

    Human vision is quantified through the use of standardized clinical vision measurements. These measurements typically include visual acuity (near and far), contrast sensitivity, color vision, stereopsis (a.k.a. stereo acuity), and visual field periphery. Simulator visual system performance is specified in terms such as brightness, contrast, color depth, color gamut, gamma, resolution, and field-of-view. How do these simulator performance characteristics relate to the perceptual experience of the pilot in the simulator? In this paper, visual acuity and contrast sensitivity will be related to simulator visual system resolution, contrast, and dynamic range; similarly, color vision will be related to color depth/color gamut. Finally, we will consider how some characteristics of human vision not typically included in current clinical assessments could be used to better inform simulator requirements (e.g., relating dynamic characteristics of human vision to update rate and other temporal display characteristics).

  20. Predictors of laparoscopic simulation performance among practicing obstetrician gynecologists.

    Science.gov (United States)

    Mathews, Shyama; Brodman, Michael; D'Angelo, Debra; Chudnoff, Scott; McGovern, Peter; Kolev, Tamara; Bensinger, Giti; Mudiraj, Santosh; Nemes, Andreea; Feldman, David; Kischak, Patricia; Ascher-Walsh, Charles

    2017-11-01

    While simulation training has been established as an effective method for improving laparoscopic surgical performance in surgical residents, few studies have focused on its use for attending surgeons, particularly in obstetrics and gynecology. Surgical simulation may have a role in improving and maintaining proficiency in the operating room for practicing obstetrician gynecologists. We sought to determine if parameters of performance for validated laparoscopic virtual simulation tasks correlate with surgical volume and characteristics of practicing obstetricians and gynecologists. All gynecologists with laparoscopic privileges (n = 347) from 5 academic medical centers in New York City were required to complete a laparoscopic surgery simulation assessment. The physicians took a presimulation survey gathering physician self-reported characteristics and then performed 3 basic skills tasks (enforced peg transfer, lifting/grasping, and cutting) on the LapSim virtual reality laparoscopic simulator (Surgical Science Ltd, Gothenburg, Sweden). The association between simulation outcome scores (time, efficiency, and errors) and self-rated clinical skills measures (self-rated laparoscopic skill score or surgical volume category) were examined with regression models. The average number of laparoscopic procedures per month was a significant predictor of total time on all 3 tasks (P = .001 for peg transfer; P = .041 for lifting and grasping; P simulation performance as it correlates to active physician practice, further studies may help assess skill and individualize training to maintain skill levels as case volumes fluctuate. Copyright © 2017 Elsevier Inc. All rights reserved.

  1. Equipment and performance upgrade of compact nuclear simulator

    International Nuclear Information System (INIS)

    Park, J. C.; Kwon, K. C.; Lee, D. Y.; Hwang, I. K.; Park, W. M.; Cha, K. H.; Song, S. J.; Lee, J. W.; Kim, B. G.; Kim, H. J.

    1999-01-01

    The simulator at Nuclear Training Center in KAERI became old and has not been used effectively for nuclear-related training and researches due to the problems such as aging of the equipment, difficulties in obtaining consumables and their high cost, and less personnel available who can handle the old equipment. To solve the problems, this study was performed for recovering the functions of the simulator through the technical design and replacement of components with new ones. As results of this study, our test after the replacement showed the same simulation status as the previous one, and new graphic displays added to the simulator was effective for the training and easy for maintenance. This study is meaningful as demonstrating the way of upgrading nuclear training simulators that lost their functioning due to the obsolescence of simulators and the unavailability of components

  2. High performance real-time flight simulation at NASA Langley

    Science.gov (United States)

    Cleveland, Jeff I., II

    1994-01-01

    In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be deterministic and be completed in as short a time as possible. This includes simulation mathematical model computational and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, personnel at NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to a standard input/output system to provide for high bandwidth, low latency data acquisition and distribution. The Computer Automated Measurement and Control technology (IEEE standard 595) was extended to meet the performance requirements for real-time simulation. This technology extension increased the effective bandwidth by a factor of ten and increased the performance of modules necessary for simulator communications. This technology is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications of this technology are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC have completed the development of the use of supercomputers for simulation mathematical model computational to support real-time flight simulation. This includes the development of a real-time operating system and the development of specialized software and hardware for the CAMAC simulator network. This work, coupled with the use of an open systems software architecture, has advanced the state of the art in real time flight simulation. The data acquisition technology innovation and experience with recent developments in this technology are described.

  3. Virtual reality simulation training of mastoidectomy - studies on novice performance.

    Science.gov (United States)

    Andersen, Steven Arild Wuyts

    2016-08-01

    Virtual reality (VR) simulation-based training is increasingly used in surgical technical skills training including in temporal bone surgery. The potential of VR simulation in enabling high-quality surgical training is great and VR simulation allows high-stakes and complex procedures such as mastoidectomy to be trained repeatedly, independent of patients and surgical tutors, outside traditional learning environments such as the OR or the temporal bone lab, and with fewer of the constraints of traditional training. This thesis aims to increase the evidence-base of VR simulation training of mastoidectomy and, by studying the final-product performances of novices, investigates the transfer of skills to the current gold-standard training modality of cadaveric dissection, the effect of different practice conditions and simulator-integrated tutoring on performance and retention of skills, and the role of directed, self-regulated learning. Technical skills in mastoidectomy were transferable from the VR simulation environment to cadaveric dissection with significant improvement in performance after directed, self-regulated training in the VR temporal bone simulator. Distributed practice led to a better learning outcome and more consolidated skills than massed practice and also resulted in a more consistent performance after three months of non-practice. Simulator-integrated tutoring accelerated the initial learning curve but also caused over-reliance on tutoring, which resulted in a drop in performance when the simulator-integrated tutor-function was discontinued. The learning curves were highly individual but often plateaued early and at an inadequate level, which related to issues concerning both the procedure and the VR simulator, over-reliance on the tutor function and poor self-assessment skills. Future simulator-integrated automated assessment could potentially resolve some of these issues and provide trainees with both feedback during the procedure and immediate

  4. Computational Fluid Dynamics and Building Energy Performance Simulation

    DEFF Research Database (Denmark)

    Nielsen, Peter V.; Tryggvason, Tryggvi

    An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution will be introduced for improvement of the predictions of both the energy consumption and the indoor environment. The building energy performance...

  5. Impact of reactive settler models on simulated WWTP performance

    DEFF Research Database (Denmark)

    Gernaey, Krist; Jeppsson, Ulf; Batstone, Damien J.

    2006-01-01

    for an ASM1 case study. Simulations with a whole plant model including the non-reactive Takacs settler model are used as a reference, and are compared to simulation results considering two reactive settler models. The first is a return sludge model block removing oxygen and a user-defined fraction of nitrate......, combined with a non-reactive Takacs settler. The second is a fully reactive ASM1 Takacs settler model. Simulations with the ASM1 reactive settler model predicted a 15.3% and 7.4% improvement of the simulated N removal performance, for constant (steady-state) and dynamic influent conditions respectively....... The oxygen/nitrate return sludge model block predicts a 10% improvement of N removal performance under dynamic conditions, and might be the better modelling option for ASM1 plants: it is computationally more efficient and it will not overrate the importance of decay processes in the settler....

  6. High performance stream computing for particle beam transport simulations

    International Nuclear Information System (INIS)

    Appleby, R; Bailey, D; Higham, J; Salt, M

    2008-01-01

    Understanding modern particle accelerators requires simulating charged particle transport through the machine elements. These simulations can be very time consuming due to the large number of particles and the need to consider many turns of a circular machine. Stream computing offers an attractive way to dramatically improve the performance of such simulations by calculating the simultaneous transport of many particles using dedicated hardware. Modern Graphics Processing Units (GPUs) are powerful and affordable stream computing devices. The results of simulations of particle transport through the booster-to-storage-ring transfer line of the DIAMOND synchrotron light source using an NVidia GeForce 7900 GPU are compared to the standard transport code MAD. It is found that particle transport calculations are suitable for stream processing and large performance increases are possible. The accuracy and potential speed gains are compared and the prospects for future work in the area are discussed

  7. Distributed dynamic simulations of networked control and building performance applications.

    Science.gov (United States)

    Yahiaoui, Azzedine

    2018-02-01

    The use of computer-based automation and control systems for smart sustainable buildings, often so-called Automated Buildings (ABs), has become an effective way to automatically control, optimize, and supervise a wide range of building performance applications over a network while achieving the minimum energy consumption possible, and in doing so generally refers to Building Automation and Control Systems (BACS) architecture. Instead of costly and time-consuming experiments, this paper focuses on using distributed dynamic simulations to analyze the real-time performance of network-based building control systems in ABs and improve the functions of the BACS technology. The paper also presents the development and design of a distributed dynamic simulation environment with the capability of representing the BACS architecture in simulation by run-time coupling two or more different software tools over a network. The application and capability of this new dynamic simulation environment are demonstrated by an experimental design in this paper.

  8. Comprehensive Simulation Lifecycle Management for High Performance Computing Modeling and Simulation, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — There are significant logistical barriers to entry-level high performance computing (HPC) modeling and simulation (M IllinoisRocstar) sets up the infrastructure for...

  9. MODELING SIMULATION AND PERFORMANCE STUDY OF GRIDCONNECTED PHOTOVOLTAIC ENERGY SYSTEM

    OpenAIRE

    Nagendra K; Karthik J; Keerthi Rao C; Kumar Raja Pemmadi

    2017-01-01

    This paper presents Modeling Simulation of grid connected Photovoltaic Energy System and performance study using MATLAB/Simulink. The Photovoltaic energy system is considered in three main parts PV Model, Power conditioning System and Grid interface. The Photovoltaic Model is inter-connected with grid through full scale power electronic devices. The simulation is conducted on the PV energy system at normal temperature and at constant load by using MATLAB.

  10. Computer Simulation Performed for Columbia Project Cooling System

    Science.gov (United States)

    Ahmad, Jasim

    2005-01-01

    This demo shows a high-fidelity simulation of the air flow in the main computer room housing the Columbia (10,024 intel titanium processors) system. The simulation asseses the performance of the cooling system and identified deficiencies, and recommended modifications to eliminate them. It used two in house software packages on NAS supercomputers: Chimera Grid tools to generate a geometric model of the computer room, OVERFLOW-2 code for fluid and thermal simulation. This state-of-the-art technology can be easily extended to provide a general capability for air flow analyses on any modern computer room. Columbia_CFD_black.tiff

  11. Simulator experiments: effects of NPP operator experience on performance

    International Nuclear Information System (INIS)

    Beare, A.N.; Gray, L.H.

    1984-01-01

    During the FY83 research, a simulator experiment was conducted at the control room simulator for a GE Boiling Water Reactor (BWR) NPP. The research subjects were licensed operators undergoing requalification training and shift technical advisors (STAs). This experiment was designed to investigate the effects of senior reactor operator (SRO) experience, operating crew augmentation with an STA and practice, as a crew, upon crew and individual operator performance, in response to anticipated plant transients. Sixteen two-man crews of licensed operators were employed in a 2 x 2 factorial design. The SROs leading the crews were split into high and low experience groups on the basis of their years of experience as an SRO. One half of the high- and low-SRO experience groups were assisted by an STA. The crews responded to four simulated plant casualties. A five-variable set of content-referenced performance measures was derived from task analyses of the procedurally correct responses to the four casualties. System parameters and control manipulations were recorded by the computer controlling the simulator. Data on communications and procedure use were obtained from analysis of videotapes of the exercises. Questionnaires were used to collect subject biographical information and data on subjective workload during each simulated casualty. For four of the five performance measures, no significant differences were found between groups led by high (25 to 114 months) and low (1 to 17 months as an SRO) experience SROs. However, crews led by low experience SROs tended to have significantly shorter task performance times than crews led by high experience SROs. The presence of the STA had no significant effect on overall team performance in responding to the four simulated casualties. The FY84 experiments are a partial replication and extension of the FY83 experiment, but with PWR operators and simulator

  12. 18th and 19th Workshop on Sustained Simulation Performance

    CERN Document Server

    Bez, Wolfgang; Focht, Erich; Kobayashi, Hiroaki; Patel, Nisarg

    2015-01-01

    This book presents the state of the art in high-performance computing and simulation on modern supercomputer architectures. It covers trends in hardware and software development in general and the future of high-performance systems and heterogeneous architectures in particular. The application-related contributions cover computational fluid dynamics, material science, medical applications and climate research; innovative fields such as coupled multi-physics and multi-scale simulations are highlighted. All papers were chosen from presentations given at the 18th Workshop on Sustained Simulation Performance held at the HLRS, University of Stuttgart, Germany in October 2013 and subsequent Workshop of the same name held at Tohoku University in March 2014.  

  13. ATES/heat pump simulations performed with ATESSS code

    Science.gov (United States)

    Vail, L. W.

    1989-01-01

    Modifications to the Aquifer Thermal Energy Storage System Simulator (ATESSS) allow simulation of aquifer thermal energy storage (ATES)/heat pump systems. The heat pump algorithm requires a coefficient of performance (COP) relationship of the form: COP = COP sub base + alpha (T sub ref minus T sub base). Initial applications of the modified ATES code to synthetic building load data for two sizes of buildings in two U.S. cities showed insignificant performance advantage of a series ATES heat pump system over a conventional groundwater heat pump system. The addition of algorithms for a cooling tower and solar array improved performance slightly. Small values of alpha in the COP relationship are the principal reason for the limited improvement in system performance. Future studies at Pacific Northwest Laboratory (PNL) are planned to investigate methods to increase system performance using alternative system configurations and operations scenarios.

  14. Simulation and performance of brushless dc motor actuators

    Science.gov (United States)

    Gerba, A., Jr.

    1985-12-01

    The simulation model for a Brushless D.C. Motor and the associated commutation power conditioner transistor model are presented. The necessary conditions for maximum power output while operating at steady-state speed and sinusoidally distributed air-gap flux are developed. Comparison of simulated model with the measured performance of a typical motor are done both on time response waveforms and on average performance characteristics. These preliminary results indicate good agreement. Plans for model improvement and testing of a motor-driven positioning device for model evaluation are outlined.

  15. Cognitive load predicts point-of-care ultrasound simulator performance.

    Science.gov (United States)

    Aldekhyl, Sara; Cavalcanti, Rodrigo B; Naismith, Laura M

    2018-02-01

    The ability to maintain good performance with low cognitive load is an important marker of expertise. Incorporating cognitive load measurements in the context of simulation training may help to inform judgements of competence. This exploratory study investigated relationships between demographic markers of expertise, cognitive load measures, and simulator performance in the context of point-of-care ultrasonography. Twenty-nine medical trainees and clinicians at the University of Toronto with a range of clinical ultrasound experience were recruited. Participants answered a demographic questionnaire then used an ultrasound simulator to perform targeted scanning tasks based on clinical vignettes. Participants were scored on their ability to both acquire and interpret ultrasound images. Cognitive load measures included participant self-report, eye-based physiological indices, and behavioural measures. Data were analyzed using a multilevel linear modelling approach, wherein observations were clustered by participants. Experienced participants outperformed novice participants on ultrasound image acquisition. Ultrasound image interpretation was comparable between the two groups. Ultrasound image acquisition performance was predicted by level of training, prior ultrasound training, and cognitive load. There was significant convergence between cognitive load measurement techniques. A marginal model of ultrasound image acquisition performance including prior ultrasound training and cognitive load as fixed effects provided the best overall fit for the observed data. In this proof-of-principle study, the combination of demographic and cognitive load measures provided more sensitive metrics to predict ultrasound simulator performance. Performance assessments which include cognitive load can help differentiate between levels of expertise in simulation environments, and may serve as better predictors of skill transfer to clinical practice.

  16. MUMAX: A new high-performance micromagnetic simulation tool

    International Nuclear Information System (INIS)

    Vansteenkiste, A.; Van de Wiele, B.

    2011-01-01

    We present MUMAX, a general-purpose micromagnetic simulation tool running on graphical processing units (GPUs). MUMAX is designed for high-performance computations and specifically targets large simulations. In that case speedups of over a factor 100 x can be obtained compared to the CPU-based OOMMF program developed at NIST. MUMAX aims to be general and broadly applicable. It solves the classical Landau-Lifshitz equation taking into account the magnetostatic, exchange and anisotropy interactions, thermal effects and spin-transfer torque. Periodic boundary conditions can optionally be imposed. A spatial discretization using finite differences in two or three dimensions can be employed. MUMAX is publicly available as open-source software. It can thus be freely used and extended by community. Due to its high computational performance, MUMAX should open up the possibility of running extensive simulations that would be nearly inaccessible with typical CPU-based simulators. - Highlights: → Novel, open-source micromagnetic simulator on GPU hardware. → Speedup of ∝100x compared to other widely used tools. → Extensively validated against standard problems. → Makes previously infeasible simulations accessible.

  17. Simulated astigmatism impairs academic-related performance in children.

    Science.gov (United States)

    Narayanasamy, Sumithira; Vincent, Stephen J; Sampson, Geoff P; Wood, Joanne M

    2015-01-01

    Astigmatism is an important refractive condition in children. However, the functional impact of uncorrected astigmatism in this population is not well established, particularly with regard to academic performance. This study investigated the impact of simulated bilateral astigmatism on academic-related tasks before and after sustained near work in children. Twenty visually normal children (mean age: 10.8 ± 0.7 years; six males and 14 females) completed a range of standardised academic-related tests with and without 1.50 D of simulated bilateral astigmatism (with both academic-related tests and the visual condition administered in a randomised order). The simulated astigmatism was induced using a positive cylindrical lens while maintaining a plano spherical equivalent. Performance was assessed before and after 20 min of sustained near work, during two separate testing sessions. Academic-related measures included a standardised reading test (the Neale Analysis of Reading Ability), visual information processing tests (Coding and Symbol Search subtests from the Wechsler Intelligence Scale for Children) and a reading-related eye movement test (the Developmental Eye Movement test). Each participant was systematically assigned either with-the-rule (WTR, axis 180°) or against-the-rule (ATR, axis 90°) simulated astigmatism to evaluate the influence of axis orientation on any decrements in performance. Reading, visual information processing and reading-related eye movement performance were all significantly impaired by both simulated bilateral astigmatism (p  0.05). Simulated astigmatism led to a reduction of between 5% and 12% in performance across the academic-related outcome measures, but there was no significant effect of the axis (WTR or ATR) of astigmatism (p > 0.05). Simulated bilateral astigmatism impaired children's performance on a range of academic-related outcome measures irrespective of the orientation of the astigmatism. These findings have

  18. Measuring cognitive load: performance, mental effort and simulation task complexity.

    Science.gov (United States)

    Haji, Faizal A; Rojas, David; Childs, Ruth; de Ribaupierre, Sandrine; Dubrowski, Adam

    2015-08-01

    Interest in applying cognitive load theory in health care simulation is growing. This line of inquiry requires measures that are sensitive to changes in cognitive load arising from different instructional designs. Recently, mental effort ratings and secondary task performance have shown promise as measures of cognitive load in health care simulation. We investigate the sensitivity of these measures to predicted differences in intrinsic load arising from variations in task complexity and learner expertise during simulation-based surgical skills training. We randomly assigned 28 novice medical students to simulation training on a simple or complex surgical knot-tying task. Participants completed 13 practice trials, interspersed with computer-based video instruction. On trials 1, 5, 9 and 13, knot-tying performance was assessed using time and movement efficiency measures, and cognitive load was assessed using subjective rating of mental effort (SRME) and simple reaction time (SRT) on a vibrotactile stimulus-monitoring secondary task. Significant improvements in knot-tying performance (F(1.04,24.95)  = 41.1, p cognitive load (F(2.3,58.5)  = 57.7, p load among novices engaged in simulation-based learning. These measures can be used to track cognitive load during skills training. Mental effort ratings are also sensitive to small differences in intrinsic load arising from variations in the physical complexity of a simulation task. The complementary nature of these subjective and objective measures suggests their combined use is advantageous in simulation instructional design research. © 2015 John Wiley & Sons Ltd.

  19. Computational Fluid Dynamics and Building Energy Performance Simulation

    DEFF Research Database (Denmark)

    Nielsen, Peter Vilhelm; Tryggvason, T.

    1998-01-01

    An interconnection between a building energy performance simulation program and a Computational Fluid Dynamics program (CFD) for room air distribution will be introduced for improvement of the predictions of both the energy consumption and the indoor environment. The building energy performance...... simulation program requires a detailed description of the energy flow in the air movement which can be obtained by a CFD program. The paper describes an energy consumption calculation in a large building, where the building energy simulation program is modified by CFD predictions of the flow between three...... zones connected by open areas with pressure and buoyancy driven air flow. The two programs are interconnected in an iterative procedure. The paper shows also an evaluation of the air quality in the main area of the buildings based on CFD predictions. It is shown that an interconnection between a CFD...

  20. Numerical Simulation and Performance Analysis of Twin Screw Air Compressors

    Directory of Open Access Journals (Sweden)

    W. S. Lee

    2001-01-01

    Full Text Available A theoretical model is proposed in this paper in order to study the performance of oil-less and oil-injected twin screw air compressors. Based on this model, a computer simulation program is developed and the effects of different design parameters including rotor profile, geometric clearance, oil-injected angle, oil temperature, oil flow rate, built-in volume ratio and other operation conditions on the performance of twin screw air compressors are investigated. The simulation program gives us output variables such as specific power, compression ratio, compression efficiency, volumetric efficiency, and discharge temperature. Some of the above results are then compared with experimentally measured data and good agreement is found between the simulation results and the measured data.

  1. INEX simulations of the optical performance of the AFEL

    International Nuclear Information System (INIS)

    Goldstein, J.C.; Wang, T.S.F.; Sheffield, R.L.

    1991-01-01

    The AFEL (Advanced Free-Electron Laser) Project at Los Alamos National Laboratory is presently under construction. The project's goal is to produce a very high-brightness electron beam which will be generated by a photocathode injector and a 20 MeV rf-linac. Initial laser experiments will be performed with a 1-cm-period permanent magnet wiggler which will generate intense optical radiation near a wavelength of 3.7 μm. Future experiments will operate with ''slotted-tube'' electromagnetic wigglers (formerly called ''pulsed- wire'' wigglers). Experiments at both fundamental and higher-harmonic wavelengths are planned. This paper presents results of INEX (Integrated Numerical EXperiment) simulations of the optical performance of the AFEL. These simulations use the electron micropulse produced by the accelerator/beam transport code PARMELA in the 3-D FEL simulation code FELEX. 9 refs., 4 figs., 6 tabs

  2. On the performance simulation of inter-stage turbine reheat

    International Nuclear Information System (INIS)

    Pellegrini, Alvise; Nikolaidis, Theoklis; Pachidis, Vassilios; Köhler, Stephan

    2017-01-01

    Highlights: • An innovative gas turbine performance simulation methodology is proposed. • It allows to perform DP and OD performance calculations for complex engines layouts. • It is essential for inter-turbine reheat (ITR) engine performance calculation. • A detailed description is provided for fast and flexible implementation. • The methodology is successfully verified against a commercial closed-source software. - Abstract: Several authors have suggested the implementation of reheat in high By-Pass Ratio (BPR) aero engines, to improve engine performance. In contrast to military afterburning, civil aero engines would aim at reducing Specific Fuel Consumption (SFC) by introducing ‘Inter-stage Turbine Reheat’ (ITR). To maximise benefits, the second combustor should be placed at an early stage of the expansion process, e.g. between the first and second High-Pressure Turbine (HPT) stages. The aforementioned cycle design requires the accurate simulation of two or more turbine stages on the same shaft. The Design Point (DP) performance can be easily evaluated by defining a Turbine Work Split (TWS) ratio between the turbine stages. However, the performance simulation of Off-Design (OD) operating points requires the calculation of the TWS parameter for every OD step, by taking into account the thermodynamic behaviour of each turbine stage, represented by their respective maps. No analytical solution of the aforementioned problem is currently available in the public domain. This paper presents an analytical methodology by which ITR can be simulated at DP and OD. Results show excellent agreement with a commercial, closed-source performance code; discrepancies range from 0% to 3.48%, and are ascribed to the different gas models implemented in the codes.

  3. High performance ultrasonic field simulation on complex geometries

    Science.gov (United States)

    Chouh, H.; Rougeron, G.; Chatillon, S.; Iehl, J. C.; Farrugia, J. P.; Ostromoukhov, V.

    2016-02-01

    Ultrasonic field simulation is a key ingredient for the design of new testing methods as well as a crucial step for NDT inspection simulation. As presented in a previous paper [1], CEA-LIST has worked on the acceleration of these simulations focusing on simple geometries (planar interfaces, isotropic materials). In this context, significant accelerations were achieved on multicore processors and GPUs (Graphics Processing Units), bringing the execution time of realistic computations in the 0.1 s range. In this paper, we present recent works that aim at similar performances on a wider range of configurations. We adapted the physical model used by the CIVA platform to design and implement a new algorithm providing a fast ultrasonic field simulation that yields nearly interactive results for complex cases. The improvements over the CIVA pencil-tracing method include adaptive strategies for pencil subdivisions to achieve a good refinement of the sensor geometry while keeping a reasonable number of ray-tracing operations. Also, interpolation of the times of flight was used to avoid time consuming computations in the impulse response reconstruction stage. To achieve the best performance, our algorithm runs on multi-core superscalar CPUs and uses high performance specialized libraries such as Intel Embree for ray-tracing, Intel MKL for signal processing and Intel TBB for parallelization. We validated the simulation results by comparing them to the ones produced by CIVA on identical test configurations including mono-element and multiple-element transducers, homogeneous, meshed 3D CAD specimens, isotropic and anisotropic materials and wave paths that can involve several interactions with interfaces. We show performance results on complete simulations that achieve computation times in the 1s range.

  4. Visuospatial ability factors and performance variables in laparoscopic simulator training

    NARCIS (Netherlands)

    Luursema, J.M.; Verwey, Willem B.; Burie, Remke

    2012-01-01

    Visuospatial ability has been shown to be important to several aspects of laparoscopic performance, including simulator training. Only a limited subset of visuospatial ability factors however has been investigated in such studies. Tests for different visuospatial ability factors differ in stimulus

  5. Atomic scale simulations for improved CRUD and fuel performance modeling

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Anders David Ragnar [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Cooper, Michael William Donald [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-01-06

    A more mechanistic description of fuel performance codes can be achieved by deriving models and parameters from atomistic scale simulations rather than fitting models empirically to experimental data. The same argument applies to modeling deposition of corrosion products on fuel rods (CRUD). Here are some results from publications in 2016 carried out using the CASL allocation at LANL.

  6. Physical Examination for Men and Women With Urologic Chronic Pelvic Pain Syndrome: A MAPP (Multidisciplinary Approach to the Study of Chronic Pelvic Pain) Network Study.

    Science.gov (United States)

    Yang, Claire C; Miller, Jane L; Omidpanah, Adam; Krieger, John N

    2018-06-01

    To examine the feasibility of implementing a standardized, clinically relevant genitourinary examination for both men and women, and to identify physical examination findings characteristic of urologic chronic pelvic pain syndrome (UCPPS). This study analyzed 2 samples: men and women with UCPPS who participated in the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network Epidemiology and Phenotyping (EP) Study, and age-matched controls who were either positive for chronic fatigue syndrome or healthy (pain-free). We compared physical examination findings in both positive and healthy controls with UCPPS cases: findings from both the EP examinations and from an extended genitourinary examination. EP and extended examinations were performed on 143 participants: 62 UCPPS cases (30 women, 32 men), 42 positive controls (15 women, 27 men), and 39 healthy controls (22 women, 17 men). EP examinations showed that pelvic floor tenderness was more prevalent in cases (55.0%) than in positive (14.6%) or healthy controls (10.5%). Extended examinations revealed specific areas of tenderness in the pelvic floor musculature. Cases were also more likely than healthy controls to report tenderness in multiple areas, including suprapubic, symphysis pubis, and posterior superior iliac spine, and on bimanual examination. No comparative findings were specific to biological sex, and no evidence of pudendal neuropathy was observed on extended examination of cases or controls. The extended genitourinary examination is an easily administered addition to the assessment of men and women during evaluation for UCPPS. Physical findings may help to better categorize patients with UCPPS into clinically relevant subgroups for optimal treatment. Published by Elsevier Inc.

  7. Simulation model of a twin-tail, high performance airplane

    Science.gov (United States)

    Buttrill, Carey S.; Arbuckle, P. Douglas; Hoffler, Keith D.

    1992-01-01

    The mathematical model and associated computer program to simulate a twin-tailed high performance fighter airplane (McDonnell Douglas F/A-18) are described. The simulation program is written in the Advanced Continuous Simulation Language. The simulation math model includes the nonlinear six degree-of-freedom rigid-body equations, an engine model, sensors, and first order actuators with rate and position limiting. A simplified form of the F/A-18 digital control laws (version 8.3.3) are implemented. The simulated control law includes only inner loop augmentation in the up and away flight mode. The aerodynamic forces and moments are calculated from a wind-tunnel-derived database using table look-ups with linear interpolation. The aerodynamic database has an angle-of-attack range of -10 to +90 and a sideslip range of -20 to +20 degrees. The effects of elastic deformation are incorporated in a quasi-static-elastic manner. Elastic degrees of freedom are not actively simulated. In the engine model, the throttle-commanded steady-state thrust level and the dynamic response characteristics of the engine are based on airflow rate as determined from a table look-up. Afterburner dynamics are switched in at a threshold based on the engine airflow and commanded thrust.

  8. The effects of fatigue on performance in simulated nursing work.

    Science.gov (United States)

    Barker, Linsey M; Nussbaum, Maury A

    2011-09-01

    Fatigue is associated with increased rates of medical errors and healthcare worker injuries, yet existing research in this sector has not considered multiple dimensions of fatigue simultaneously. This study evaluated hypothesised causal relationships between mental and physical fatigue and performance. High and low levels of mental and physical fatigue were induced in 16 participants during simulated nursing work tasks in a laboratory setting. Task-induced changes in fatigue dimensions were quantified using both subjective and objective measures, as were changes in performance on physical and mental tasks. Completing the simulated work tasks increased total fatigue, mental fatigue and physical fatigue in all experimental conditions. Higher physical fatigue adversely affected measures of physical and mental performance, whereas higher mental fatigue had a positive effect on one measure of mental performance. Overall, these results suggest causal effects between manipulated levels of mental and physical fatigue and task-induced changes in mental and physical performance. STATEMENT OF RELEVANCE: Nurse fatigue and performance has implications for patient and provider safety. Results from this study demonstrate the importance of a multidimensional view of fatigue in understanding the causal relationships between fatigue and performance. The findings can guide future work aimed at predicting fatigue-related performance decrements and designing interventions.

  9. Water desalination price from recent performances: Modelling, simulation and analysis

    International Nuclear Information System (INIS)

    Metaiche, M.; Kettab, A.

    2005-01-01

    The subject of the present article is the technical simulation of seawater desalination, by a one stage reverse osmosis system, the objectives of which are the recent valuation of cost price through the use of new membrane and permeator performances, the use of new means of simulation and modelling of desalination parameters, and show the main parameters influencing the cost price. We have taken as the simulation example the Seawater Desalting centre of Djannet (Boumerdes, Algeria). The present performances allow water desalting at a price of 0.5 $/m 3 , which is an interesting and promising price, corresponding with the very acceptable water product quality, in the order of 269 ppm. It is important to run the desalting systems by reverse osmosis under high pressure, resulting in further decrease of the desalting cost and the production of good quality water. Aberration in choice of functioning conditions produces high prices and unacceptable quality. However there exists the possibility of decreasing the price by decreasing the requirement on the product quality. The seawater temperature has an effect on the cost price and quality. The installation of big desalting centres, contributes to the decrease in prices. A very important, long and tedious calculation is effected, which is impossible to conduct without programming and informatics tools. The use of the simulation model has been much efficient in the design of desalination centres that can perform at very improved prices. (author)

  10. Facility/equipment performance evaluation using microcomputer simulation analysis

    International Nuclear Information System (INIS)

    Chockie, A.D.; Hostick, C.J.

    1985-08-01

    A computer simulation analysis model was developed at the Pacific Northwest Laboratory to assist in assuring the adequacy of the Monitored Retrievable Storage facility design to meet the specified spent nuclear fuel throughput requirements. The microcomputer-based model was applied to the analysis of material flow, equipment capability and facility layout. The simulation analysis evaluated uncertainties concerning both facility throughput requirements and process duration times as part of the development of a comprehensive estimate of facility performance. The evaluations provided feedback into the design review task to identify areas where design modifications should be considered

  11. Imaging Performance Analysis of Simbol-X with Simulations

    Science.gov (United States)

    Chauvin, M.; Roques, J. P.

    2009-05-01

    Simbol-X is an X-Ray telescope operating in formation flight. It means that its optical performances will strongly depend on the drift of the two spacecrafts and its ability to measure these drifts for image reconstruction. We built a dynamical ray tracing code to study the impact of these parameters on the optical performance of Simbol-X (see Chauvin et al., these proceedings). Using the simulation tool we have developed, we have conducted detailed analyses of the impact of different parameters on the imaging performance of the Simbol-X telescope.

  12. Imaging Performance Analysis of Simbol-X with Simulations

    International Nuclear Information System (INIS)

    Chauvin, M.; Roques, J. P.

    2009-01-01

    Simbol-X is an X-Ray telescope operating in formation flight. It means that its optical performances will strongly depend on the drift of the two spacecrafts and its ability to measure these drifts for image reconstruction. We built a dynamical ray tracing code to study the impact of these parameters on the optical performance of Simbol-X (see Chauvin et al., these proceedings). Using the simulation tool we have developed, we have conducted detailed analyses of the impact of different parameters on the imaging performance of the Simbol-X telescope.

  13. Visualization and Analysis of Climate Simulation Performance Data

    Science.gov (United States)

    Röber, Niklas; Adamidis, Panagiotis; Behrens, Jörg

    2015-04-01

    Visualization is the key process of transforming abstract (scientific) data into a graphical representation, to aid in the understanding of the information hidden within the data. Climate simulation data sets are typically quite large, time varying, and consist of many different variables sampled on an underlying grid. A large variety of climate models - and sub models - exist to simulate various aspects of the climate system. Generally, one is mainly interested in the physical variables produced by the simulation runs, but model developers are also interested in performance data measured along with these simulations. Climate simulation models are carefully developed complex software systems, designed to run in parallel on large HPC systems. An important goal thereby is to utilize the entire hardware as efficiently as possible, that is, to distribute the workload as even as possible among the individual components. This is a very challenging task, and detailed performance data, such as timings, cache misses etc. have to be used to locate and understand performance problems in order to optimize the model implementation. Furthermore, the correlation of performance data to the processes of the application and the sub-domains of the decomposed underlying grid is vital when addressing communication and load imbalance issues. High resolution climate simulations are carried out on tens to hundreds of thousands of cores, thus yielding a vast amount of profiling data, which cannot be analyzed without appropriate visualization techniques. This PICO presentation displays and discusses the ICON simulation model, which is jointly developed by the Max Planck Institute for Meteorology and the German Weather Service and in partnership with DKRZ. The visualization and analysis of the models performance data allows us to optimize and fine tune the model, as well as to understand its execution on the HPC system. We show and discuss our workflow, as well as present new ideas and

  14. Neurocognitive Correlates of Young Drivers' Performance in a Driving Simulator.

    Science.gov (United States)

    Guinosso, Stephanie A; Johnson, Sara B; Schultheis, Maria T; Graefe, Anna C; Bishai, David M

    2016-04-01

    Differences in neurocognitive functioning may contribute to driving performance among young drivers. However, few studies have examined this relation. This pilot study investigated whether common neurocognitive measures were associated with driving performance among young drivers in a driving simulator. Young drivers (19.8 years (standard deviation [SD] = 1.9; N = 74)) participated in a battery of neurocognitive assessments measuring general intellectual capacity (Full-Scale Intelligence Quotient, FSIQ) and executive functioning, including the Stroop Color-Word Test (cognitive inhibition), Wisconsin Card Sort Test-64 (cognitive flexibility), and Attention Network Task (alerting, orienting, and executive attention). Participants then drove in a simulated vehicle under two conditions-a baseline and driving challenge. During the driving challenge, participants completed a verbal working memory task to increase demand on executive attention. Multiple regression models were used to evaluate the relations between the neurocognitive measures and driving performance under the two conditions. FSIQ, cognitive inhibition, and alerting were associated with better driving performance at baseline. FSIQ and cognitive inhibition were also associated with better driving performance during the verbal challenge. Measures of cognitive flexibility, orienting, and conflict executive control were not associated with driving performance under either condition. FSIQ and, to some extent, measures of executive function are associated with driving performance in a driving simulator. Further research is needed to determine if executive function is associated with more advanced driving performance under conditions that demand greater cognitive load. Copyright © 2016 Society for Adolescent Health and Medicine. Published by Elsevier Inc. All rights reserved.

  15. Performance evaluation of sea surface simulation methods for target detection

    Science.gov (United States)

    Xia, Renjie; Wu, Xin; Yang, Chen; Han, Yiping; Zhang, Jianqi

    2017-11-01

    With the fast development of sea surface target detection by optoelectronic sensors, machine learning has been adopted to improve the detection performance. Many features can be learned from training images by machines automatically. However, field images of sea surface target are not sufficient as training data. 3D scene simulation is a promising method to address this problem. For ocean scene simulation, sea surface height field generation is the key point to achieve high fidelity. In this paper, two spectra-based height field generation methods are evaluated. Comparison between the linear superposition and linear filter method is made quantitatively with a statistical model. 3D ocean scene simulating results show the different features between the methods, which can give reference for synthesizing sea surface target images with different ocean conditions.

  16. Performance simulation of a MRPC-based PET imaging system

    Science.gov (United States)

    Roy, A.; Banerjee, A.; Biswas, S.; Chattopadhyay, S.; Das, G.; Saha, S.

    2014-10-01

    The less expensive and high resolution Multi-gap Resistive Plate Chamber (MRPC) opens up a new possibility to find an efficient alternative detector for the Time of Flight (TOF) based Positron Emission Tomography, where the sensitivity of the system depends largely on the time resolution of the detector. In a layered structure, suitable converters can be used to increase the photon detection efficiency. In this work, we perform a detailed GEANT4 simulation to optimize the converter thickness towards improving the efficiency of photon conversion. A Monte Carlo based procedure has been developed to simulate the time resolution of the MRPC-based system, making it possible to simulate its response for PET imaging application. The results of the test of a six-gap MRPC, operating in avalanche mode, with 22Na source have been discussed.

  17. Software life cycle dynamic simulation model: The organizational performance submodel

    Science.gov (United States)

    Tausworthe, Robert C.

    1985-01-01

    The submodel structure of a software life cycle dynamic simulation model is described. The software process is divided into seven phases, each with product, staff, and funding flows. The model is subdivided into an organizational response submodel, a management submodel, a management influence interface, and a model analyst interface. The concentration here is on the organizational response model, which simulates the performance characteristics of a software development subject to external and internal influences. These influences emanate from two sources: the model analyst interface, which configures the model to simulate the response of an implementing organization subject to its own internal influences, and the management submodel that exerts external dynamic control over the production process. A complete characterization is given of the organizational response submodel in the form of parameterized differential equations governing product, staffing, and funding levels. The parameter values and functions are allocated to the two interfaces.

  18. Numerical simulation investigation on centrifugal compressor performance of turbocharger

    International Nuclear Information System (INIS)

    Li, Jie; Yin, Yuting; Li, Shuqi; Zhang, Jizhong

    2013-01-01

    In this paper, the mathematical model of the flow filed in centrifugal compressor of turbocharger was studied. Based on the theory of computational fluid dynamics (CFD), performance curves and parameter distributions of the compressor were obtained from the 3-D numerical simulation by using CFX. Meanwhile, the influences of grid number and distribution on compressor performance were investigated, and numerical calculation method was analyzed and validated, through combining with test data. The results obtained show the increase of the grid number has little influence on compressor performance while the grid number of single-passage is above 300,000. The results also show that the numerical calculation mass flow rate of compressor choke situation has a good consistent with test results, and the maximum difference of the diffuser exit pressure between simulation and experiment decrease to 3.5% with the assumption of 6 kPa additional total pressure loss at compressor inlet. The numerical simulation method in this paper can be used to predict compressor performance, and the difference of total pressure ratio between calculation and test is less than 7%, and the total-to-total efficiency also have a good consistent with test.

  19. Adaptive Performance-Constrained in Situ Visualization of Atmospheic Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Dorier, Matthieu; Sisneros, Roberto; Bautista Gomez, Leonard; Peterka, Tom; Orf, Leigh; Rahmani, Lokman; Antoniu, Gabriel; Bouge, Luc

    2016-09-12

    While many parallel visualization tools now provide in situ visualization capabilities, the trend has been to feed such tools with large amounts of unprocessed output data and let them render everything at the highest possible resolution. This leads to an increased run time of simulations that still have to complete within a fixed-length job allocation. In this paper, we tackle the challenge of enabling in situ visualization under performance constraints. Our approach shuffles data across processes according to its content and filters out part of it in order to feed a visualization pipeline with only a reorganized subset of the data produced by the simulation. Our framework leverages fast, generic evaluation procedures to score blocks of data, using information theory, statistics, and linear algebra. It monitors its own performance and adapts dynamically to achieve appropriate visual fidelity within predefined performance constraints. Experiments on the Blue Waters supercomputer with the CM1 simulation show that our approach enables a 5 speedup with respect to the initial visualization pipeline and is able to meet performance constraints.

  20. Performance measurement system for training simulators. Interim report

    International Nuclear Information System (INIS)

    Bockhold, G. Jr.; Roth, D.R.

    1978-05-01

    In the first project phase, the project team has designed, installed, and test run on the Browns Ferry nuclear power plant training simulator a performance measurement system capable of automatic recording of statistical information on operator actions and plant response. Key plant variables and operator actions were monitored and analyzed by the simulator computer for a selected set of four operating and casualty drills. The project has the following objectives: (1) To provide an empirical data base for statistical analysis of operator reliability and for allocation of safety and control functions between operators and automated controls; (2) To develop a method for evaluation of the effectiveness of control room designs and operating procedures; and (3) To develop a system for scoring aspects of operator performance to assist in training evaluations and to support operator selection research. The performance measurement system has shown potential for meeting the research objectives. However, the cost of training simulator time is high; to keep research program costs reasonable, the measurement system is being designed to be an integral part of operator training programs. In the pilot implementation, participating instructors judged the measurement system to be a valuable and objective extension of their abilities to monitor trainee performance

  1. Numerical simulation investigation on centrifugal compressor performance of turbocharger

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jie [China Iron and Steel Research Institute Group, Beijing (China); Yin, Yuting [China North Engine Research Institute, Datong (China); Li, Shuqi; Zhang, Jizhong [Science and Technology Diesel Engine Turbocharging Laboratory, Datong (China)

    2013-06-15

    In this paper, the mathematical model of the flow filed in centrifugal compressor of turbocharger was studied. Based on the theory of computational fluid dynamics (CFD), performance curves and parameter distributions of the compressor were obtained from the 3-D numerical simulation by using CFX. Meanwhile, the influences of grid number and distribution on compressor performance were investigated, and numerical calculation method was analyzed and validated, through combining with test data. The results obtained show the increase of the grid number has little influence on compressor performance while the grid number of single-passage is above 300,000. The results also show that the numerical calculation mass flow rate of compressor choke situation has a good consistent with test results, and the maximum difference of the diffuser exit pressure between simulation and experiment decrease to 3.5% with the assumption of 6 kPa additional total pressure loss at compressor inlet. The numerical simulation method in this paper can be used to predict compressor performance, and the difference of total pressure ratio between calculation and test is less than 7%, and the total-to-total efficiency also have a good consistent with test.

  2. Fully Coupled Simulation of Lithium Ion Battery Cell Performance

    Energy Technology Data Exchange (ETDEWEB)

    Trembacki, Bradley L. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Murthy, Jayathi Y. [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Roberts, Scott Alan [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States)

    2015-09-01

    Lithium-ion battery particle-scale (non-porous electrode) simulations applied to resolved electrode geometries predict localized phenomena and can lead to better informed decisions on electrode design and manufacturing. This work develops and implements a fully-coupled finite volume methodology for the simulation of the electrochemical equations in a lithium-ion battery cell. The model implementation is used to investigate 3D battery electrode architectures that offer potential energy density and power density improvements over traditional layer-by-layer particle bed battery geometries. Advancement of micro-scale additive manufacturing techniques has made it possible to fabricate these 3D electrode microarchitectures. A variety of 3D battery electrode geometries are simulated and compared across various battery discharge rates and length scales in order to quantify performance trends and investigate geometrical factors that improve battery performance. The energy density and power density of the 3D battery microstructures are compared in several ways, including a uniform surface area to volume ratio comparison as well as a comparison requiring a minimum manufacturable feature size. Significant performance improvements over traditional particle bed electrode designs are observed, and electrode microarchitectures derived from minimal surfaces are shown to be superior. A reduced-order volume-averaged porous electrode theory formulation for these unique 3D batteries is also developed, allowing simulations on the full-battery scale. Electrode concentration gradients are modeled using the diffusion length method, and results for plate and cylinder electrode geometries are compared to particle-scale simulation results. Additionally, effective diffusion lengths that minimize error with respect to particle-scale results for gyroid and Schwarz P electrode microstructures are determined.

  3. Simulator experiments: effects of NPP operator experience on performance

    International Nuclear Information System (INIS)

    Beare, A.N.; Gray, L.H.

    1985-01-01

    Experiments are being conducted on nuclear power plant (NPP) control room training simulators by the Oak Ridge National Laboratory, its subcontractor, General Physics Corporation, and participating utilities. The experiments are sponsored by the Nuclear Regulatory Commission's (NRC) Human Factors and Safeguards Branch, Division of Risk Analysis and Operations, and are a continuation of prior research using simulators, supported by field data collection, to provide a technical basis for NRC human factors regulatory issues concerned with the operational safety of nuclear power plants. During the FY83 research, a simulator experiment was conducted at the control room simulator for a GE boiling water reactor (BWR) NPP. The research subjects were licensed operators undergoing requalification training and shift technical advisors (STAs). This experiment was designed to investigate the effects of (a) senior reactor operator (SRO) experience, (b) operating crew augmentation with an STA and (c) practice, as a crew, upon crew and individual operator performance, in response to anticipated plant transients. The FY84 experiments are a partial replication and extension of the FY83 experiment, but with PWR operators and simulator. Methodology and results to date are reported

  4. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    Directory of Open Access Journals (Sweden)

    M. Norhafana

    2015-11-01

    Full Text Available Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of a solar water heating system as well as to evaluate the performance of the solar collector in terms of useful heat of the multilayered absorber using the multidirectional ability of a solar simulator at several values of solar radiation. It is operated at three variables of solar radiation of 400 W/m2, 550 W/m2 and 700 W/m2 and using three different positions of angles at 0º, 45º and 90º. The results show that the multilayer absorber in the solar collector is only able to best adapt at 45° of solar simulator with different values of radiation intensity. At this angle the maximum values of useful heat and temperature difference are achieved. KEYWORDS: solar water heating system; solar collector; multilayered absorber; solar simulator; solar radiation 

  5. Comparison of driving simulator performance and neuropsychological testing in narcolepsy.

    Science.gov (United States)

    Kotterba, Sylvia; Mueller, Nicole; Leidag, Markus; Widdig, Walter; Rasche, Kurt; Malin, Jean-Pierre; Schultze-Werninghaus, Gerhard; Orth, Maritta

    2004-09-01

    Daytime sleepiness and cataplexy can increase automobile accident rates in narcolepsy. Several countries have produced guidelines for issuing a driving license. The aim of the study was to compare driving simulator performance and neuropsychological test results in narcolepsy in order to evaluate their predictive value regarding driving ability. Thirteen patients with narcolepsy (age: 41.5+/-12.9 years) and 10 healthy control patients (age: 55.1+/-7.8 years) were investigated. By computer-assisted neuropsychological testing, vigilance, alertness and divided attention were assessed. In a driving simulator patients and controls had to drive on a highway for 60 min (mean speed of 100 km/h). Different weather and daytime conditions and obstacles were presented. Epworth Sleepiness Scale-Scores were significantly raised (narcolepsy patients: 16.7+/-5.1, controls: 6.6+/-3.6, P divided attention (56.9+/-25.4) and vigilance (58.7+/-26.8) were in a normal range. There was, however, a high inter-individual difference. There was no correlation between driving performance and neuropsychological test results or ESS Score. Neuropsychological test results did not significantly change in the follow-up. The difficulties encountered by the narcolepsy patient in remaining alert may account for sleep-related motor vehicle accidents. Driving simulator investigations are closely related to real traffic situations than isolated neuropsychological tests. At the present time the driving simulator seems to be a useful instrument judging driving ability especially in cases with ambiguous neuropsychological results.

  6. Performance Analysis of Cloud Computing Architectures Using Discrete Event Simulation

    Science.gov (United States)

    Stocker, John C.; Golomb, Andrew M.

    2011-01-01

    Cloud computing offers the economic benefit of on-demand resource allocation to meet changing enterprise computing needs. However, the flexibility of cloud computing is disadvantaged when compared to traditional hosting in providing predictable application and service performance. Cloud computing relies on resource scheduling in a virtualized network-centric server environment, which makes static performance analysis infeasible. We developed a discrete event simulation model to evaluate the overall effectiveness of organizations in executing their workflow in traditional and cloud computing architectures. The two part model framework characterizes both the demand using a probability distribution for each type of service request as well as enterprise computing resource constraints. Our simulations provide quantitative analysis to design and provision computing architectures that maximize overall mission effectiveness. We share our analysis of key resource constraints in cloud computing architectures and findings on the appropriateness of cloud computing in various applications.

  7. The new rosetta targets observations, simulations and instrument performances

    CERN Document Server

    Epifani, Elena; Palumbo, Pasquale

    2004-01-01

    The Rosetta mission was successfully launched on March 2nd, 2004 for a rendezvous with the short period comet 67PChuryumov-Gerasimenko in 2014 The new baseline mission foresees also a double fly-by with asteroids 21 Lutetia and 2867 Steins, on the way towards the primary target This volume collects papers presented at the workshop on "The NEW Rosetta targets Observations, simulations and instrument performances", held in Capri on October 13-15, 2003 The papers cover the fields of observations of the new Rosetta targets, laboratory experiments and theoretical simulation of cometary processes, and the expected performances of Rosetta experiments Until real operations around 67PChuryumov-Gerasimenko will start in 10 years from now, new astronomical observations, laboratory experiments and theoretical models are required The goals are to increase knowledge about physics and chemistry of comets and to prepare to exploit at best Rosetta data

  8. PERFORMANCE EVALUATION OF SOLAR COLLECTORS USING A SOLAR SIMULATOR

    OpenAIRE

    M. Norhafana; Ahmad Faris Ismail; Z. A. A. Majid

    2015-01-01

    Solar water heating systems is one of the applications of solar energy. One of the components of a solar water heating system is a solar collector that consists of an absorber. The performance of the solar water heating system depends on the absorber in the solar collector. In countries with unsuitable weather conditions, the indoor testing of solar collectors with the use of a solar simulator is preferred. Thus, this study is conducted to use a multilayered absorber in the solar collector of...

  9. Sustainable construction building performance simulation and asset and maintenance management

    CERN Document Server

    2016-01-01

    This book presents a collection of recent research works that highlight best practice solutions, case studies and practical advice on the implementation of sustainable construction techniques. It includes a set of new developments in the field of building performance simulation, building sustainability assessment, sustainable management, asset and maintenance management and service-life prediction. Accordingly, the book will appeal to a broad readership of professionals, scientists, students, practitioners, lecturers and other interested parties.

  10. Use of advanced simulations in fuel performance codes

    International Nuclear Information System (INIS)

    Van Uffelen, P.

    2015-01-01

    The simulation of the cylindrical fuel rod behaviour in a reactor or a storage pool for spent fuel requires a fuel performance code. Such tool solves the equations for the heat transfer, the stresses and strains in fuel and cladding, the evolution of several isotopes and the behaviour of various fission products in the fuel rod. The main equations along with their limitations are briefly described. The current approaches adopted for overcoming these limitations and the perspectives are also outlined. (author)

  11. Simulations

    CERN Document Server

    Ngada, Narcisse

    2015-06-15

    The complexity and cost of building and running high-power electrical systems make the use of simulations unavoidable. The simulations available today provide great understanding about how systems really operate. This paper helps the reader to gain an insight into simulation in the field of power converters for particle accelerators. Starting with the definition and basic principles of simulation, two simulation types, as well as their leading tools, are presented: analog and numerical simulations. Some practical applications of each simulation type are also considered. The final conclusion then summarizes the main important items to keep in mind before opting for a simulation tool or before performing a simulation.

  12. Robust Multivariable Optimization and Performance Simulation for ASIC Design

    Science.gov (United States)

    DuMonthier, Jeffrey; Suarez, George

    2013-01-01

    Application-specific-integrated-circuit (ASIC) design for space applications involves multiple challenges of maximizing performance, minimizing power, and ensuring reliable operation in extreme environments. This is a complex multidimensional optimization problem, which must be solved early in the development cycle of a system due to the time required for testing and qualification severely limiting opportunities to modify and iterate. Manual design techniques, which generally involve simulation at one or a small number of corners with a very limited set of simultaneously variable parameters in order to make the problem tractable, are inefficient and not guaranteed to achieve the best possible results within the performance envelope defined by the process and environmental requirements. What is required is a means to automate design parameter variation, allow the designer to specify operational constraints and performance goals, and to analyze the results in a way that facilitates identifying the tradeoffs defining the performance envelope over the full set of process and environmental corner cases. The system developed by the Mixed Signal ASIC Group (MSAG) at the Goddard Space Flight Center is implemented as a framework of software modules, templates, and function libraries. It integrates CAD tools and a mathematical computing environment, and can be customized for new circuit designs with only a modest amount of effort as most common tasks are already encapsulated. Customization is required for simulation test benches to determine performance metrics and for cost function computation.

  13. Simulating the Performance of Ground-Based Optical Asteroid Surveys

    Science.gov (United States)

    Christensen, Eric J.; Shelly, Frank C.; Gibbs, Alex R.; Grauer, Albert D.; Hill, Richard E.; Johnson, Jess A.; Kowalski, Richard A.; Larson, Stephen M.

    2014-11-01

    We are developing a set of asteroid survey simulation tools in order to estimate the capability of existing and planned ground-based optical surveys, and to test a variety of possible survey cadences and strategies. The survey simulator is composed of several layers, including a model population of solar system objects and an orbital integrator, a site-specific atmospheric model (including inputs for seeing, haze and seasonal cloud cover), a model telescope (with a complete optical path to estimate throughput), a model camera (including FOV, pixel scale, and focal plane fill factor) and model source extraction and moving object detection layers with tunable detection requirements. We have also developed a flexible survey cadence planning tool to automatically generate nightly survey plans. Inputs to the cadence planner include camera properties (FOV, readout time), telescope limits (horizon, declination, hour angle, lunar and zenithal avoidance), preferred and restricted survey regions in RA/Dec, ecliptic, and Galactic coordinate systems, and recent coverage by other asteroid surveys. Simulated surveys are created for a subset of current and previous NEO surveys (LINEAR, Pan-STARRS and the three Catalina Sky Survey telescopes), and compared against the actual performance of these surveys in order to validate the model’s performance. The simulator tracks objects within the FOV of any pointing that were not discovered (e.g. too few observations, too trailed, focal plane array gaps, too fast or slow), thus dividing the population into “discoverable” and “discovered” subsets, to inform possible survey design changes. Ongoing and future work includes generating a realistic “known” subset of the model NEO population, running multiple independent simulated surveys in coordinated and uncoordinated modes, and testing various cadences to find optimal strategies for detecting NEO sub-populations. These tools can also assist in quantifying the efficiency of novel

  14. Predictive neuromechanical simulations indicate why walking performance declines with ageing.

    Science.gov (United States)

    Song, Seungmoon; Geyer, Hartmut

    2018-04-01

    Although the natural decline in walking performance with ageing affects the quality of life of a growing elderly population, its physiological origins remain unknown. By using predictive neuromechanical simulations of human walking with age-related neuro-musculo-skeletal changes, we find evidence that the loss of muscle strength and muscle contraction speed dominantly contribute to the reduced walking economy and speed. The findings imply that focusing on recovering these muscular changes may be the only effective way to improve performance in elderly walking. More generally, the work is of interest for investigating the physiological causes of altered gait due to age, injury and disorders. Healthy elderly people walk slower and energetically less efficiently than young adults. This decline in walking performance lowers the quality of life for a growing ageing population, and understanding its physiological origin is critical for devising interventions that can delay or revert it. However, the origin of the decline in walking performance remains unknown, as ageing produces a range of physiological changes whose individual effects on gait are difficult to separate in experiments with human subjects. Here we use a predictive neuromechanical model to separately address the effects of common age-related changes to the skeletal, muscular and nervous systems. We find in computer simulations of this model that the combined changes produce gait consistent with elderly walking and that mainly the loss of muscle strength and mass reduces energy efficiency. In addition, we find that the slower preferred walking speed of elderly people emerges in the simulations when adapting to muscle fatigue, again mainly caused by muscle-related changes. The results suggest that a focus on recovering these muscular changes may be the only effective way to improve performance in elderly walking. © 2018 The Authors. The Journal of Physiology © 2018 The Physiological Society.

  15. Simulations of KSTAR high performance steady state operation scenarios

    International Nuclear Information System (INIS)

    Na, Yong-Su; Kessel, C.E.; Park, J.M.; Yi, Sumin; Kim, J.Y.; Becoulet, A.; Sips, A.C.C.

    2009-01-01

    We report the results of predictive modelling of high performance steady state operation scenarios in KSTAR. Firstly, the capabilities of steady state operation are investigated with time-dependent simulations using a free-boundary plasma equilibrium evolution code coupled with transport calculations. Secondly, the reproducibility of high performance steady state operation scenarios developed in the DIII-D tokamak, of similar size to that of KSTAR, is investigated using the experimental data taken from DIII-D. Finally, the capability of ITER-relevant steady state operation is investigated in KSTAR. It is found that KSTAR is able to establish high performance steady state operation scenarios; β N above 3, H 98 (y, 2) up to 2.0, f BS up to 0.76 and f NI equals 1.0. In this work, a realistic density profile is newly introduced for predictive simulations by employing the scaling law of a density peaking factor. The influence of the current ramp-up scenario and the transport model is discussed with respect to the fusion performance and non-inductive current drive fraction in the transport simulations. As observed in the experiments, both the heating and the plasma current waveforms in the current ramp-up phase produce a strong effect on the q-profile, the fusion performance and also on the non-inductive current drive fraction in the current flattop phase. A criterion in terms of q min is found to establish ITER-relevant steady state operation scenarios. This will provide a guideline for designing the current ramp-up phase in KSTAR. It is observed that the transport model also affects the predictive values of fusion performance as well as the non-inductive current drive fraction. The Weiland transport model predicts the highest fusion performance as well as non-inductive current drive fraction in KSTAR. In contrast, the GLF23 model exhibits the lowest ones. ITER-relevant advanced scenarios cannot be obtained with the GLF23 model in the conditions given in this work

  16. Resting-state functional connectivity predicts longitudinal pain symptom change in urologic chronic pelvic pain syndrome: a MAPP network study.

    Science.gov (United States)

    Kutch, Jason J; Labus, Jennifer S; Harris, Richard E; Martucci, Katherine T; Farmer, Melissa A; Fenske, Sonja; Fling, Connor; Ichesco, Eric; Peltier, Scott; Petre, Bogdan; Guo, Wensheng; Hou, Xiaoling; Stephens, Alisa J; Mullins, Chris; Clauw, Daniel J; Mackey, Sean C; Apkarian, A Vania; Landis, J Richard; Mayer, Emeran A

    2017-06-01

    Chronic pain symptoms often change over time, even in individuals who have had symptoms for years. Studying biological factors that predict trends in symptom change in chronic pain may uncover novel pathophysiological mechanisms and potential therapeutic targets. In this study, we investigated whether brain functional connectivity measures obtained from resting-state functional magnetic resonance imaging at baseline can predict longitudinal symptom change (3, 6, and 12 months after scan) in urologic chronic pelvic pain syndrome. We studied 52 individuals with urologic chronic pelvic pain syndrome (34 women, 18 men) who had baseline neuroimaging followed by symptom tracking every 2 weeks for 1 year as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP) Research Network study. We found that brain functional connectivity can make a significant prediction of short-term (3 month) pain reduction with 73.1% accuracy (69.2% sensitivity and 75.0% precision). In addition, we found that the brain regions with greatest contribution to the classification were preferentially aligned with the left frontoparietal network. Resting-state functional magnetic resonance imaging measures seemed to be less informative about 6- or 12-month symptom change. Our study provides the first evidence that future trends in symptom change in patients in a state of chronic pain may be linked to functional connectivity within specific brain networks.

  17. Alcohol consumption for simulated driving performance: A systematic review.

    Science.gov (United States)

    Rezaee-Zavareh, Mohammad Saeid; Salamati, Payman; Ramezani-Binabaj, Mahdi; Saeidnejad, Mina; Rousta, Mansoureh; Shokraneh, Farhad; Rahimi-Movaghar, Vafa

    2017-06-01

    Alcohol consumption can lead to risky driving and increase the frequency of traffic accidents, injuries and mortalities. The main purpose of our study was to compare simulated driving performance between two groups of drivers, one consumed alcohol and the other not consumed, using a systematic review. In this systematic review, electronic resources and databases including Medline via Ovid SP, EMBASE via Ovid SP, PsycINFO via Ovid SP, PubMed, Scopus, Cumulative Index to Nursing and Allied Health Literature (CINHAL) via EBSCOhost were comprehensively and systematically searched. The randomized controlled clinical trials that compared simulated driving performance between two groups of drivers, one consumed alcohol and the other not consumed, were included. Lane position standard deviation (LPSD), mean of lane position deviation (MLPD), speed, mean of speed deviation (MSD), standard deviation of speed deviation (SDSD), number of accidents (NA) and line crossing (LC) were considered as the main parameters evaluating outcomes. After title and abstract screening, the articles were enrolled for data extraction and they were evaluated for risk of biases. Thirteen papers were included in our qualitative synthesis. All included papers were classified as high risk of biases. Alcohol consumption mostly deteriorated the following performance outcomes in descending order: SDSD, LPSD, speed, MLPD, LC and NA. Our systematic review had troublesome heterogeneity. Alcohol consumption may decrease simulated driving performance in alcohol consumed people compared with non-alcohol consumed people via changes in SDSD, LPSD, speed, MLPD, LC and NA. More well-designed randomized controlled clinical trials are recommended. Copyright © 2017. Production and hosting by Elsevier B.V.

  18. Alcohol consumption for simulated driving performance: A systematic review

    Institute of Scientific and Technical Information of China (English)

    Mohammad Saeid Rezaee-Zavareh; Payman Salamati; Mahdi Ramezani-Binabaj; Mina Saeidnejad; Mansoureh Rousta; Farhad Shokraneh; Vafa Rahimi-Movaghar

    2017-01-01

    Purpose:Alcohol consumption can lead to risky driving and increase the frequency of traffic accidents,injuries and mortalities.The main purpose of our study was to compare simulated driving performance between two groups of drivers,one consumed alcohol and the other not consumed,using a systematic review.Methods:In this systematic review,electronic resources and databases including Medline via Ovid SP,EMBASE via Ovid SP,PsycINFO via Ovid SP,PubMed,Scopus,Cumulative Index to Nursing and Allied Health Literature (CINHAL) via EBSCOhost were comprehensively and systematically searched.The randomized controlled clinical trials that compared simulated driving performance between two groups of drivers,one consumed alcohol and the other not consumed,were included.Lane position standard deviation (LPSD),mean of lane position deviation (MLPD),speed,mean of speed deviation (MSD),standard deviation of speed deviation (SDSD),number of accidents (NA) and line crossing (LC) were considered as the main parameters evaluating outcomes.After title and abstract screening,the articles were enrolled for data extraction and they were evaluated for risk of biases.Results:Thirteen papers were included in our qualitative synthesis.All included papers were classified as high risk of biases.Alcohol consumption mostly deteriorated the following performance outcomes in descending order:SDSD,LPSD,speed,MLPD,LC and NA.Our systematic review had troublesome heterogeneity.Conclusion:Alcohol consumption may decrease simulated driving performance in alcohol consumed people compared with non-alcohol consumed people via changes in SDSD,LPSD,speed,MLPD,LC and NA.More well-designed randomized controlled clinical trials are recommended.

  19. Building Performance Simulation tools for planning of energy efficiency retrofits

    DEFF Research Database (Denmark)

    Mondrup, Thomas Fænø; Karlshøj, Jan; Vestergaard, Flemming

    2014-01-01

    Designing energy efficiency retrofits for existing buildings will bring environmental, economic, social, and health benefits. However, selecting specific retrofit strategies is complex and requires careful planning. In this study, we describe a methodology for adopting Building Performance...... to energy efficiency retrofits in social housing. To generate energy savings, we focus on optimizing the building envelope. We evaluate alternative building envelope actions using procedural solar radiation and daylight simulations. In addition, we identify the digital information flow and the information...... Simulation (BPS) tools as energy and environmentally conscious decision-making aids. The methodology has been developed to screen buildings for potential improvements and to support the development of retrofit strategies. We present a case study of a Danish renovation project, implementing BPS approaches...

  20. Hybrid Building Performance Simulation Models for Industrial Energy Efficiency Applications

    Directory of Open Access Journals (Sweden)

    Peter Smolek

    2018-06-01

    Full Text Available In the challenge of achieving environmental sustainability, industrial production plants, as large contributors to the overall energy demand of a country, are prime candidates for applying energy efficiency measures. A modelling approach using cubes is used to decompose a production facility into manageable modules. All aspects of the facility are considered, classified into the building, energy system, production and logistics. This approach leads to specific challenges for building performance simulations since all parts of the facility are highly interconnected. To meet this challenge, models for the building, thermal zones, energy converters and energy grids are presented and the interfaces to the production and logistics equipment are illustrated. The advantages and limitations of the chosen approach are discussed. In an example implementation, the feasibility of the approach and models is shown. Different scenarios are simulated to highlight the models and the results are compared.

  1. Acoustic performance of industrial mufflers with CAE modeling and simulation

    Directory of Open Access Journals (Sweden)

    Jeon Soohong

    2014-12-01

    Full Text Available This paper investigates the noise transmission performance of industrial mufflers widely used in ships based on the CAE modeling and simulation. Since the industrial mufflers have very complicated internal structures, the conventional Transfer Matrix Method (TMM is of limited use. The CAE modeling and simulation is therefore required to incorporate commercial softwares: CATIA for geometry modeling, MSC/PATRAN for FE meshing and LMS/ SYSNOISE for analysis. Main sources of difficulties in this study are led by complicated arrangement of reactive elements, perforated walls and absorption materials. The reactive elements and absorbent materials are modeled by applying boundary conditions given by impedance. The perforated walls are modeled by applying the transfer impedance on the duplicated node mesh. The CAE approach presented in this paper is verified by comparing with the theoretical solution of a concentric-tube resonator and is applied for industrial mufflers.

  2. Acoustic performance of industrial mufflers with CAE modeling and simulation

    Directory of Open Access Journals (Sweden)

    Soohong Jeon

    2014-12-01

    Full Text Available This paper investigates the noise transmission performance of industrial mufflers widely used in ships based on the CAE modeling and simulation. Since the industrial mufflers have very complicated internal structures, the conventional Transfer Matrix Method (TMM is of limited use. The CAE modeling and simulation is therefore required to incorporate commercial softwares: CATIA for geometry modeling, MSC/PATRAN for FE meshing and LMS/SYSNOISE for analysis. Main sources of difficulties in this study are led by complicated arrangement of reactive ele- ments, perforated walls and absorption materials. The reactive elements and absorbent materials are modeled by applying boundary conditions given by impedance. The perforated walls are modeled by applying the transfer impedance on the duplicated node mesh. The CAE approach presented in this paper is verified by comparing with the theoretical solution of a concentric-tube resonator and is applied for industrial mufflers.

  3. Management of Industrial Performance Indicators: Regression Analysis and Simulation

    Directory of Open Access Journals (Sweden)

    Walter Roberto Hernandez Vergara

    2017-11-01

    Full Text Available Stochastic methods can be used in problem solving and explanation of natural phenomena through the application of statistical procedures. The article aims to associate the regression analysis and systems simulation, in order to facilitate the practical understanding of data analysis. The algorithms were developed in Microsoft Office Excel software, using statistical techniques such as regression theory, ANOVA and Cholesky Factorization, which made it possible to create models of single and multiple systems with up to five independent variables. For the analysis of these models, the Monte Carlo simulation and analysis of industrial performance indicators were used, resulting in numerical indices that aim to improve the goals’ management for compliance indicators, by identifying systems’ instability, correlation and anomalies. The analytical models presented in the survey indicated satisfactory results with numerous possibilities for industrial and academic applications, as well as the potential for deployment in new analytical techniques.

  4. Performance demonstration program plan for analysis of simulated headspace gases

    International Nuclear Information System (INIS)

    1995-06-01

    The Performance Demonstration Program (PDP) for analysis of headspace gases will consist of regular distribution and analyses of test standards to evaluate the capability for analyzing VOCs, hydrogen, and methane in the headspace of transuranic (TRU) waste throughout the Department of Energy (DOE) complex. Each distribution is termed a PDP cycle. These evaluation cycles will provide an objective measure of the reliability of measurements performed for TRU waste characterization. Laboratory performance will be demonstrated by the successful analysis of blind audit samples of simulated TRU waste drum headspace gases according to the criteria set within the text of this Program Plan. Blind audit samples (hereinafter referred to as PDP samples) will be used as an independent means to assess laboratory performance regarding compliance with the QAPP QAOs. The concentration of analytes in the PDP samples will encompass the range of concentrations anticipated in actual waste characterization gas samples. Analyses which are required by the WIPP to demonstrate compliance with various regulatory requirements and which are included in the PDP must be performed by laboratories which have demonstrated acceptable performance in the PDP

  5. High performance thermal stress analysis on the earth simulator

    International Nuclear Information System (INIS)

    Noriyuki, Kushida; Hiroshi, Okuda; Genki, Yagawa

    2003-01-01

    In this study, the thermal stress finite element analysis code optimized for the earth simulator was developed. A processor node of which of the earth simulator is the 8-way vector processor, and each processor can communicate using the message passing interface. Thus, there are two ways to parallelize the finite element method on the earth simulator. The first method is to assign one processor for one sub-domain, and the second method is to assign one node (=8 processors) for one sub-domain considering the shared memory type parallelization. Considering that the preconditioned conjugate gradient (PCG) method, which is one of the suitable linear equation solvers for the large-scale parallel finite element methods, shows the better convergence behavior if the number of domains is the smaller, we have determined to employ PCG and the hybrid parallelization, which is based on the shared and distributed memory type parallelization. It has been said that it is hard to obtain the good parallel or vector performance, since the finite element method is based on unstructured grids. In such situation, the reordering is inevitable to improve the computational performance [2]. In this study, we used three reordering methods, i.e. Reverse Cuthil-McKee (RCM), cyclic multicolor (CM) and diagonal jagged descending storage (DJDS)[3]. RCM provides the good convergence of the incomplete lower-upper (ILU) PCG, but causes the load imbalance. On the other hand, CM provides the good load balance, but worsens the convergence of ILU PCG if the vector length is so long. Therefore, we used the combined-method of RCM and CM. DJDS is the method to store the sparse matrices such that longer vector length can be obtained. For attaining the efficient inter-node parallelization, such partitioning methods as the recursive coordinate bisection (RCM) or MeTIS have been used. Computational performance of the practical large-scale engineering problems will be shown at the meeting. (author)

  6. Assessing performance and validating finite element simulations using probabilistic knowledge

    Energy Technology Data Exchange (ETDEWEB)

    Dolin, Ronald M.; Rodriguez, E. A. (Edward A.)

    2002-01-01

    Two probabilistic approaches for assessing performance are presented. The first approach assesses probability of failure by simultaneously modeling all likely events. The probability each event causes failure along with the event's likelihood of occurrence contribute to the overall probability of failure. The second assessment method is based on stochastic sampling using an influence diagram. Latin-hypercube sampling is used to stochastically assess events. The overall probability of failure is taken as the maximum probability of failure of all the events. The Likelihood of Occurrence simulation suggests failure does not occur while the Stochastic Sampling approach predicts failure. The Likelihood of Occurrence results are used to validate finite element predictions.

  7. Crystal and molecular simulation of high-performance polymers.

    Science.gov (United States)

    Colquhoun, H M; Williams, D J

    2000-03-01

    Single-crystal X-ray analyses of oligomeric models for high-performance aromatic polymers, interfaced to computer-based molecular modeling and diffraction simulation, have enabled the determination of a range of previously unknown polymer crystal structures from X-ray powder data. Materials which have been successfully analyzed using this approach include aromatic polyesters, polyetherketones, polythioetherketones, polyphenylenes, and polycarboranes. Pure macrocyclic homologues of noncrystalline polyethersulfones afford high-quality single crystals-even at very large ring sizes-and have provided the first examples of a "protein crystallographic" approach to the structures of conventionally amorphous synthetic polymers.

  8. Eddy current NDE performance demonstrations using simulation tools

    International Nuclear Information System (INIS)

    Maurice, L.; Costan, V.; Guillot, E.; Thomas, P.

    2013-01-01

    To carry out performance demonstrations of the Eddy-Current NDE processes applied on French nuclear power plants, EDF studies the possibility of using simulation tools as an alternative to measurements on steam generator tube mocks-up. This paper focuses on the strategy led by EDF to assess and use code C armel3D and Civa, on the case of Eddy-Current NDE on wears problem which may appear in the U-shape region of steam generator tubes due to the rubbing of anti-vibration bars.

  9. Simulation of a spintronic transistor: A study of its performance

    International Nuclear Information System (INIS)

    Pela, R.R.; Teles, L.K.

    2009-01-01

    We study theoretically the magnetic bipolar transistor, and compare its performance with common bipolar transistor. We present not only the simulation results for the characteristic curves, but also other relevant parameters related with its performance, such as: the current amplification factor, the open-loop gain, the hybrid parameters and the cutoff frequency. We noted that the spin-charge coupling introduces new phenomena that enrich the functionality characteristics of the magnetic bipolar transistor. Among other things, it has an adjustable band structure, which may be modified during the device operation; it exhibits the already known spin-voltaic effect. On the other hand, we observed that it is necessary a large g-factor to analyze the influence of the field B over the transistor. Nevertheless, we consider the magnetic bipolar transistor as a promising device for spintronic applications

  10. Mixed-Language High-Performance Computing for Plasma Simulations

    Directory of Open Access Journals (Sweden)

    Quanming Lu

    2003-01-01

    Full Text Available Java is receiving increasing attention as the most popular platform for distributed computing. However, programmers are still reluctant to embrace Java as a tool for writing scientific and engineering applications due to its still noticeable performance drawbacks compared with other programming languages such as Fortran or C. In this paper, we present a hybrid Java/Fortran implementation of a parallel particle-in-cell (PIC algorithm for plasma simulations. In our approach, the time-consuming components of this application are designed and implemented as Fortran subroutines, while less calculation-intensive components usually involved in building the user interface are written in Java. The two types of software modules have been glued together using the Java native interface (JNI. Our mixed-language PIC code was tested and its performance compared with pure Java and Fortran versions of the same algorithm on a Sun E6500 SMP system and a Linux cluster of Pentium~III machines.

  11. A New Model to Simulate Energy Performance of VRF Systems

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Tianzhen; Pang, Xiufeng; Schetrit, Oren; Wang, Liping; Kasahara, Shinichi; Yura, Yoshinori; Hinokuma, Ryohei

    2014-03-30

    This paper presents a new model to simulate energy performance of variable refrigerant flow (VRF) systems in heat pump operation mode (either cooling or heating is provided but not simultaneously). The main improvement of the new model is the introduction of the evaporating and condensing temperature in the indoor and outdoor unit capacity modifier functions. The independent variables in the capacity modifier functions of the existing VRF model in EnergyPlus are mainly room wet-bulb temperature and outdoor dry-bulb temperature in cooling mode and room dry-bulb temperature and outdoor wet-bulb temperature in heating mode. The new approach allows compliance with different specifications of each indoor unit so that the modeling accuracy is improved. The new VRF model was implemented in a custom version of EnergyPlus 7.2. This paper first describes the algorithm for the new VRF model, which is then used to simulate the energy performance of a VRF system in a Prototype House in California that complies with the requirements of Title 24 ? the California Building Energy Efficiency Standards. The VRF system performance is then compared with three other types of HVAC systems: the Title 24-2005 Baseline system, the traditional High Efficiency system, and the EnergyStar Heat Pump system in three typical California climates: Sunnyvale, Pasadena and Fresno. Calculated energy savings from the VRF systems are significant. The HVAC site energy savings range from 51 to 85percent, while the TDV (Time Dependent Valuation) energy savings range from 31 to 66percent compared to the Title 24 Baseline Systems across the three climates. The largest energy savings are in Fresno climate followed by Sunnyvale and Pasadena. The paper discusses various characteristics of the VRF systems contributing to the energy savings. It should be noted that these savings are calculated using the Title 24 prototype House D under standard operating conditions. Actual performance of the VRF systems for real

  12. High performance computer code for molecular dynamics simulations

    International Nuclear Information System (INIS)

    Levay, I.; Toekesi, K.

    2007-01-01

    Complete text of publication follows. Molecular Dynamics (MD) simulation is a widely used technique for modeling complicated physical phenomena. Since 2005 we are developing a MD simulations code for PC computers. The computer code is written in C++ object oriented programming language. The aim of our work is twofold: a) to develop a fast computer code for the study of random walk of guest atoms in Be crystal, b) 3 dimensional (3D) visualization of the particles motion. In this case we mimic the motion of the guest atoms in the crystal (diffusion-type motion), and the motion of atoms in the crystallattice (crystal deformation). Nowadays, it is common to use Graphics Devices in intensive computational problems. There are several ways to use this extreme processing performance, but never before was so easy to programming these devices as now. The CUDA (Compute Unified Device) Architecture introduced by nVidia Corporation in 2007 is a very useful for every processor hungry application. A Unified-architecture GPU include 96-128, or more stream processors, so the raw calculation performance is 576(!) GFLOPS. It is ten times faster, than the fastest dual Core CPU [Fig.1]. Our improved MD simulation software uses this new technology, which speed up our software and the code run 10 times faster in the critical calculation code segment. Although the GPU is a very powerful tool, it has a strongly paralleled structure. It means, that we have to create an algorithm, which works on several processors without deadlock. Our code currently uses 256 threads, shared and constant on-chip memory, instead of global memory, which is 100 times slower than others. It is possible to implement the total algorithm on GPU, therefore we do not need to download and upload the data in every iteration. On behalf of maximal throughput, every thread run with the same instructions

  13. Instrument performance and simulation verification of the POLAR detector

    Science.gov (United States)

    Kole, M.; Li, Z. H.; Produit, N.; Tymieniecka, T.; Zhang, J.; Zwolinska, A.; Bao, T. W.; Bernasconi, T.; Cadoux, F.; Feng, M. Z.; Gauvin, N.; Hajdas, W.; Kong, S. W.; Li, H. C.; Li, L.; Liu, X.; Marcinkowski, R.; Orsi, S.; Pohl, M.; Rybka, D.; Sun, J. C.; Song, L. M.; Szabelski, J.; Wang, R. J.; Wang, Y. H.; Wen, X.; Wu, B. B.; Wu, X.; Xiao, H. L.; Xiong, S. L.; Zhang, L.; Zhang, L. Y.; Zhang, S. N.; Zhang, X. F.; Zhang, Y. J.; Zhao, Y.

    2017-11-01

    POLAR is a new satellite-born detector aiming to measure the polarization of an unprecedented number of Gamma-Ray Bursts in the 50-500 keV energy range. The instrument, launched on-board the Tiangong-2 Chinese Space lab on the 15th of September 2016, is designed to measure the polarization of the hard X-ray flux by measuring the distribution of the azimuthal scattering angles of the incoming photons. A detailed understanding of the polarimeter and specifically of the systematic effects induced by the instrument's non-uniformity are required for this purpose. In order to study the instrument's response to polarization, POLAR underwent a beam test at the European Synchrotron Radiation Facility in France. In this paper both the beam test and the instrument performance will be described. This is followed by an overview of the Monte Carlo simulation tools developed for the instrument. Finally a comparison of the measured and simulated instrument performance will be provided and the instrument response to polarization will be presented.

  14. Wireless network simulation - Your window on future network performance

    NARCIS (Netherlands)

    Fledderus, E.

    2005-01-01

    The paper describes three relevant perspectives on current wireless simulation practices. In order to obtain the key challenges for future network simulations, the characteristics of "beyond 3G" networks are described, including their impact on simulation.

  15. Solar power plant performance evaluation: simulation and experimental validation

    International Nuclear Information System (INIS)

    Natsheh, E M; Albarbar, A

    2012-01-01

    In this work the performance of solar power plant is evaluated based on a developed model comprise photovoltaic array, battery storage, controller and converters. The model is implemented using MATLAB/SIMULINK software package. Perturb and observe (P and O) algorithm is used for maximizing the generated power based on maximum power point tracker (MPPT) implementation. The outcome of the developed model are validated and supported by a case study carried out using operational 28.8kW grid-connected solar power plant located in central Manchester. Measurements were taken over 21 month's period; using hourly average irradiance and cell temperature. It was found that system degradation could be clearly monitored by determining the residual (the difference) between the output power predicted by the model and the actual measured power parameters. It was found that the residual exceeded the healthy threshold, 1.7kW, due to heavy snow in Manchester last winter. More important, the developed performance evaluation technique could be adopted to detect any other reasons that may degrade the performance of the P V panels such as shading and dirt. Repeatability and reliability of the developed system performance were validated during this period. Good agreement was achieved between the theoretical simulation and the real time measurement taken the online grid connected solar power plant.

  16. Solar power plant performance evaluation: simulation and experimental validation

    Science.gov (United States)

    Natsheh, E. M.; Albarbar, A.

    2012-05-01

    In this work the performance of solar power plant is evaluated based on a developed model comprise photovoltaic array, battery storage, controller and converters. The model is implemented using MATLAB/SIMULINK software package. Perturb and observe (P&O) algorithm is used for maximizing the generated power based on maximum power point tracker (MPPT) implementation. The outcome of the developed model are validated and supported by a case study carried out using operational 28.8kW grid-connected solar power plant located in central Manchester. Measurements were taken over 21 month's period; using hourly average irradiance and cell temperature. It was found that system degradation could be clearly monitored by determining the residual (the difference) between the output power predicted by the model and the actual measured power parameters. It was found that the residual exceeded the healthy threshold, 1.7kW, due to heavy snow in Manchester last winter. More important, the developed performance evaluation technique could be adopted to detect any other reasons that may degrade the performance of the P V panels such as shading and dirt. Repeatability and reliability of the developed system performance were validated during this period. Good agreement was achieved between the theoretical simulation and the real time measurement taken the online grid connected solar power plant.

  17. Learning through simulated independent practice leads to better future performance in a simulated crisis than learning through simulated supervised practice.

    Science.gov (United States)

    Goldberg, A; Silverman, E; Samuelson, S; Katz, D; Lin, H M; Levine, A; DeMaria, S

    2015-05-01

    Anaesthetists may fail to recognize and manage certain rare intraoperative events. Simulation has been shown to be an effective educational adjunct to typical operating room-based education to train for these events. It is yet unclear, however, why simulation has any benefit. We hypothesize that learners who are allowed to manage a scenario independently and allowed to fail, thus causing simulated morbidity, will consequently perform better when re-exposed to a similar scenario. Using a randomized, controlled, observer-blinded design, 24 first-year residents were exposed to an oxygen pipeline contamination scenario, either where patient harm occurred (independent group, n=12) or where a simulated attending anaesthetist intervened to prevent harm (supervised group, n=12). Residents were brought back 6 months later and exposed to a different scenario (pipeline contamination) with the same end point. Participants' proper treatment, time to diagnosis, and non-technical skills (measured using the Anaesthetists' Non-Technical Skills Checklist, ANTS) were measured. No participants provided proper treatment in the initial exposure. In the repeat encounter 6 months later, 67% in the independent group vs 17% in the supervised group resumed adequate oxygen delivery (P=0.013). The independent group also had better ANTS scores [median (interquartile range): 42.3 (31.5-53.1) vs 31.3 (21.6-41), P=0.015]. There was no difference in time to treatment if proper management was provided [602 (490-820) vs 610 (420-800) s, P=0.79]. Allowing residents to practise independently in the simulation laboratory, and subsequently, allowing them to fail, can be an important part of simulation-based learning. This is not feasible in real clinical practice but appears to have improved resident performance in this study. The purposeful use of independent practice and its potentially negative outcomes thus sets simulation-based learning apart from traditional operating room learning. © The Author

  18. Generating performance portable geoscientific simulation code with Firedrake (Invited)

    Science.gov (United States)

    Ham, D. A.; Bercea, G.; Cotter, C. J.; Kelly, P. H.; Loriant, N.; Luporini, F.; McRae, A. T.; Mitchell, L.; Rathgeber, F.

    2013-12-01

    This presentation will demonstrate how a change in simulation programming paradigm can be exploited to deliver sophisticated simulation capability which is far easier to programme than are conventional models, is capable of exploiting different emerging parallel hardware, and is tailored to the specific needs of geoscientific simulation. Geoscientific simulation represents a grand challenge computational task: many of the largest computers in the world are tasked with this field, and the requirements of resolution and complexity of scientists in this field are far from being sated. However, single thread performance has stalled, even sometimes decreased, over the last decade, and has been replaced by ever more parallel systems: both as conventional multicore CPUs and in the emerging world of accelerators. At the same time, the needs of scientists to couple ever-more complex dynamics and parametrisations into their models makes the model development task vastly more complex. The conventional approach of writing code in low level languages such as Fortran or C/C++ and then hand-coding parallelism for different platforms by adding library calls and directives forces the intermingling of the numerical code with its implementation. This results in an almost impossible set of skill requirements for developers, who must simultaneously be domain science experts, numericists, software engineers and parallelisation specialists. Even more critically, it requires code to be essentially rewritten for each emerging hardware platform. Since new platforms are emerging constantly, and since code owners do not usually control the procurement of the supercomputers on which they must run, this represents an unsustainable development load. The Firedrake system, conversely, offers the developer the opportunity to write PDE discretisations in the high-level mathematical language UFL from the FEniCS project (http://fenicsproject.org). Non-PDE model components, such as parametrisations

  19. Analysis of TIMS performance subjected to simulated wind blast

    Science.gov (United States)

    Jaggi, S.; Kuo, S.

    1992-01-01

    The results of the performance of the Thermal Infrared Multispectral Scanner (TIMS) when it is subjected to various wind conditions in the laboratory are described. Various wind conditions were simulated using a 24 inch fan or combinations of air jet streams blowing toward either or both of the blackbody surfaces. The fan was used to simulate a large volume of air flow at moderate speeds (up to 30 mph). The small diameter air jets were used to probe TIMS system response in reaction to localized wind perturbations. The maximum nozzle speed of the air jet was 60 mph. A range of wind directions and speeds were set up in the laboratory during the test. The majority of the wind tests were conducted under ambient conditions with the room temperature fluctuating no more than 2 C. The temperature of the high speed air jet was determined to be within 1 C of the room temperature. TIMS response was recorded on analog tape. Additional thermistor readouts of the blackbody temperatures and thermocouple readout of the ambient temperature were recorded manually to be compared with the housekeeping data recorded on the tape. Additional tests were conducted under conditions of elevated and cooled room temperatures. The room temperature was varied between 19.5 to 25.5 C in these tests. The calibration parameters needed for quantitative analysis of TIMS data were first plotted on a scanline-by-scanline basis. These parameters are the low and high blackbody temperature readings as recorded by the TIMS and their corresponding digitized count values. Using these values, the system transfer equations were calculated. This equation allows us to compute the flux for any video count by computing the slope and intercept of the straight line that relates the flux to the digital count. The actual video of the target (the lab floor in this case) was then compared with a simulated target. This simulated target was assumed to be a blackbody at emissivity of .95 degrees and the temperature was

  20. Near peripheral motion contrast threshold predicts older drivers' simulator performance.

    Science.gov (United States)

    Henderson, Steven; Gagnon, Sylvain; Collin, Charles; Tabone, Ricardo; Stinchcombe, Arne

    2013-01-01

    Our group has previously demonstrated that peripheral motion contrast threshold (PMCT) is significantly associated with self-reported accident risk of older drivers (questionnaire assessment), and with Useful Field of View(®) subtest 2 (UFOV2). It has not been shown, however, that PMCT is significantly associated with driving performance. Using the method of descending limits (spatial two-alternative forced choice) we assessed motion contrast thresholds of 28 young participants (25-45), and 21 older drivers (63-86) for 0.4 cycle/degree drifting Gabor stimuli at 15° eccentricity and examined whether it was related to performance on a simulated on-road test and to a measure of visual attention (UFOV(®) subtests 2 and 3). Peripheral motion contrast thresholds (PMCT) of younger participants were significantly lower than older participants. PMCT and UFOV2 significantly predicted driving examiners' scores of older drivers' simulator performance, as well as number of crashes. Within the older group, PMCT correlated significantly with UFOV2, UFOV3, and age. Within the younger group, PMCT was not significantly related to either UFOV(®) scores or age. Partial correlations showed that: substantial association between PMCT and UFOV2 was not age-related (within the older driver group); PMCT and UFOV2 tapped a common visual function; and PMCT assessed a component not captured by UFOV2. PMCT is potentially a useful assessment tool for predicting accident risk of older drivers, and for informing efforts to develop effective countermeasures to remediate this functional deficit as much as possible. Copyright © 2012 Elsevier Ltd. All rights reserved.

  1. Altered resting state neuromotor connectivity in men with chronic prostatitis/chronic pelvic pain syndrome: A MAPP

    Directory of Open Access Journals (Sweden)

    Jason J. Kutch

    2015-01-01

    Full Text Available Brain network activity associated with altered motor control in individuals with chronic pain is not well understood. Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS is a debilitating condition in which previous studies have revealed altered resting pelvic floor muscle activity in men with CP/CPPS compared to healthy controls. We hypothesized that the brain networks controlling pelvic floor muscles would also show altered resting state function in men with CP/CPPS. Here we describe the results of the first test of this hypothesis focusing on the motor cortical regions, termed pelvic-motor, that can directly activate pelvic floor muscles. A group of men with CP/CPPS (N = 28, as well as group of age-matched healthy male controls (N = 27, had resting state functional magnetic resonance imaging scans as part of the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP Research Network study. Brain maps of the functional connectivity of pelvic-motor were compared between groups. A significant group difference was observed in the functional connectivity between pelvic-motor and the right posterior insula. The effect size of this group difference was among the largest effect sizes in functional connectivity between all pairs of 165 anatomically-defined subregions of the brain. Interestingly, many of the atlas region pairs with large effect sizes also involved other subregions of the insular cortices. We conclude that functional connectivity between motor cortex and the posterior insula may be among the most important markers of altered brain function in men with CP/CPPS, and may represent changes in the integration of viscerosensory and motor processing.

  2. Modeling and Analysis of Power Processing Systems (MAPPS). Volume 1: Technical report

    Science.gov (United States)

    Lee, F. C.; Rahman, S.; Carter, R. A.; Wu, C. H.; Yu, Y.; Chang, R.

    1980-01-01

    Computer aided design and analysis techniques were applied to power processing equipment. Topics covered include: (1) discrete time domain analysis of switching regulators for performance analysis; (2) design optimization of power converters using augmented Lagrangian penalty function technique; (3) investigation of current-injected multiloop controlled switching regulators; and (4) application of optimization for Navy VSTOL energy power system. The generation of the mathematical models and the development and application of computer aided design techniques to solve the different mathematical models are discussed. Recommendations are made for future work that would enhance the application of the computer aided design techniques for power processing systems.

  3. Performance Simulations for a Spaceborne Methane Lidar Mission

    Science.gov (United States)

    Kiemle, C.; Kawa, Stephan Randolph; Quatrevalet, Mathieu; Browell, Edward V.

    2014-01-01

    Future spaceborne lidar measurements of key anthropogenic greenhouse gases are expected to close current observational gaps particularly over remote, polar, and aerosol-contaminated regions, where actual in situ and passive remote sensing observation techniques have difficulties. For methane, a "Methane Remote Lidar Mission" was proposed by Deutsches Zentrum fuer Luft- und Raumfahrt and Centre National d'Etudes Spatiales in the frame of a German-French climate monitoring initiative. Simulations assess the performance of this mission with the help of Moderate Resolution Imaging Spectroradiometer and Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations of the earth's surface albedo and atmospheric optical depth. These are key environmental parameters for integrated path differential absorption lidar which uses the surface backscatter to measure the total atmospheric methane column. Results showthat a lidar with an average optical power of 0.45W at 1.6 µm wavelength and a telescope diameter of 0.55 m, installed on a low Earth orbit platform(506 km), will measure methane columns at precisions of 1.2%, 1.7%, and 2.1% over land, water, and snow or ice surfaces, respectively, for monthly aggregated measurement samples within areas of 50 × 50 km2. Globally, the mean precision for the simulated year 2007 is 1.6%, with a standard deviation of 0.7%. At high latitudes, a lower reflectance due to snow and ice is compensated by denser measurements, owing to the orbital pattern. Over key methane source regions such as densely populated areas, boreal and tropical wetlands, or permafrost, our simulations show that the measurement precision will be between 1 and 2%.

  4. Performance Demonstration Program Plan for Analysis of Simulated Headspace Gases

    International Nuclear Information System (INIS)

    2006-01-01

    The Performance Demonstration Program (PDP) for headspace gases distributes sample gases of volatile organic compounds (VOCs) for analysis. Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardous Waste Facility Permit (NM4890139088-TSDF) issued by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility's compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document. Participating measurement

  5. Performance Demonstration Program Plan for Analysis of Simulated Headspace Gases

    International Nuclear Information System (INIS)

    2007-01-01

    The Performance Demonstration Program (PDP) for headspace gases distributes blind audit samples in a gas matrix for analysis of volatile organic compounds (VOCs). Participating measurement facilities (i.e., fixed laboratories, mobile analysis systems, and on-line analytical systems) are located across the United States. Each sample distribution is termed a PDP cycle. These evaluation cycles provide an objective measure of the reliability of measurements performed for transuranic (TRU) waste characterization. The primary documents governing the conduct of the PDP are the Quality Assurance Program Document (QAPD) (DOE/CBFO-94-1012) and the Waste Isolation Pilot Plant (WIPP) Waste Analysis Plan (WAP) contained in the Hazardous Waste Facility Permit (NM4890139088-TSDF) issued by the New Mexico Environment Department (NMED). The WAP requires participation in the PDP; the PDP must comply with the QAPD and the WAP. This plan implements the general requirements of the QAPD and the applicable requirements of the WAP for the Headspace Gas (HSG) PDP. Participating measurement facilities analyze blind audit samples of simulated TRU waste package headspace gases according to the criteria set by this PDP Plan. Blind audit samples (hereafter referred to as PDP samples) are used as an independent means to assess each measurement facility's compliance with the WAP quality assurance objectives (QAOs). To the extent possible, the concentrations of VOC analytes in the PDP samples encompass the range of concentrations anticipated in actual TRU waste package headspace gas samples. Analyses of headspace gases are required by the WIPP to demonstrate compliance with regulatory requirements. These analyses must be performed by measurement facilities that have demonstrated acceptable performance in this PDP. These analyses are referred to as WIPP analyses and the TRU waste package headspace gas samples on which they are performed are referred to as WIPP samples in this document

  6. Numerical simulation of hydrodynamic performance of ship under oblique conditions

    Directory of Open Access Journals (Sweden)

    CHEN Zhiming

    2018-02-01

    Full Text Available [Objectives] This paper is intended to study the viscous flow field around a ship under oblique conditions and provide a research basis for ship maneuverability. [Methods] Using commercial software STRA-CCM+, the SST k-ω turbulence model is selected to predict the hydrodynamic performance of the KVLCC2 model at different drift angles, and predict the hull flow field. The pressure distribution of the ship model at different drift angles is observed and the vortex shedding of the ship's hull and constraint streamlines on the hull's surface are also observed. [Results] The results show that numerical simulation can satisfy the demands of engineering application in the prediction of the lateral force, yaw moment and hull surface pressure distribution of a ship. [Conclusions] The research results of this paper can provide valuable references for the study of the flow separation phenomenon under oblique conditions.

  7. Battery Performance Modelling ad Simulation: a Neural Network Based Approach

    Science.gov (United States)

    Ottavianelli, Giuseppe; Donati, Alessandro

    2002-01-01

    This project has developed on the background of ongoing researches within the Control Technology Unit (TOS-OSC) of the Special Projects Division at the European Space Operations Centre (ESOC) of the European Space Agency. The purpose of this research is to develop and validate an Artificial Neural Network tool (ANN) able to model, simulate and predict the Cluster II battery system's performance degradation. (Cluster II mission is made of four spacecraft flying in tetrahedral formation and aimed to observe and study the interaction between sun and earth by passing in and out of our planet's magnetic field). This prototype tool, named BAPER and developed with a commercial neural network toolbox, could be used to support short and medium term mission planning in order to improve and maximise the batteries lifetime, determining which are the future best charge/discharge cycles for the batteries given their present states, in view of a Cluster II mission extension. This study focuses on the five Silver-Cadmium batteries onboard of Tango, the fourth Cluster II satellite, but time restrains have allowed so far to perform an assessment only on the first battery. In their most basic form, ANNs are hyper-dimensional curve fits for non-linear data. With their remarkable ability to derive meaning from complicated or imprecise history data, ANN can be used to extract patterns and detect trends that are too complex to be noticed by either humans or other computer techniques. ANNs learn by example, and this is why they can be described as an inductive, or data-based models for the simulation of input/target mappings. A trained ANN can be thought of as an "expert" in the category of information it has been given to analyse, and this expert can then be used, as in this project, to provide projections given new situations of interest and answer "what if" questions. The most appropriate algorithm, in terms of training speed and memory storage requirements, is clearly the Levenberg

  8. Behavioral Simulation and Performance Evaluation of Multi-Processor Architectures

    Directory of Open Access Journals (Sweden)

    Ausif Mahmood

    1996-01-01

    Full Text Available The development of multi-processor architectures requires extensive behavioral simulations to verify the correctness of design and to evaluate its performance. A high level language can provide maximum flexibility in this respect if the constructs for handling concurrent processes and a time mapping mechanism are added. This paper describes a novel technique for emulating hardware processes involved in a parallel architecture such that an object-oriented description of the design is maintained. The communication and synchronization between hardware processes is handled by splitting the processes into their equivalent subprograms at the entry points. The proper scheduling of these subprograms is coordinated by a timing wheel which provides a time mapping mechanism. Finally, a high level language pre-processor is proposed so that the timing wheel and the process emulation details can be made transparent to the user.

  9. Using Performance in Multiple Simulated Scenarios to Assess Bronchoscopy Skills

    DEFF Research Database (Denmark)

    Konge, Lars; Arendrup, Henrik; Buchwald, Christian von

    2011-01-01

    using a standardized scoring form. Methods: The test was administered on a virtual reality bronchoscopy simulator to a total of 42 test subjects (14 senior consultants, 14 trainees and 14 medical students). The inter-rater reliability of the test procedure was explored according to examination of test......Background: International guidelines suggest that trainees should perform at least 100 flexible bronchoscopies in a supervised setting, but this number is not evidence based. An objective assessment method could provide educational feedback to trainees and help supervisors decide when basic...... competency is established. No former assessment instrument has been able to distinguish between trainees and experts. Objectives: The aim of this study was to explore the validity and reliability of a new assessment procedure relating to testing operators across multiple tasks with increasing difficulty...

  10. Predictability of Pilot Performance from Simulated to Real Flight in the UH-60 (Black Hawk) Helicopter

    Science.gov (United States)

    2008-02-01

    keratectomy ( PRK ) and laser in-situ keratomileusis ( LASIK ) procedures to determine compatibility, safety, and efficacy of these procedures for rated Army...performance data. Table B- 1. Simulator and aircraft mean flight performance. LASIK PRK Simulator Aircraft Simulator Aircraft Pre-op 60.81 (2.65) 56.41...12 7. Aircraft vs . Simulator scatter plot, hover turn maneuvers

  11. Implementing Data Acquisition Systems DAS1 and DAS2 at Cernavoda Full-Scope Simulator Main Control Room based on the SIEN2007 solution

    International Nuclear Information System (INIS)

    Ionescu, Ana Maria; Tutuianu, Bogdan; Ionescu, Teodor

    2009-01-01

    Modern personnel training, re-training and licensing is a guarantee of NPP's safe reliable operation. Cernavoda NPP personnel training system is the main objective of its specialized department built up as Training Center (TC), directly supervised by Administration of the National Nuclearelectrica Society (SNN) and National Regulatory Body for Nuclear Activities (CNCAN). It was implemented to ensure the abilities, skills and knowledge required by the safe reliable operation of the nuclear reactor by the Main Control Room (MCR) operators. This objective was reached through training lessons taught and tested on the Full Scope Simulator (FSS), the TC's main training tool, a replica of the MCR of the real plant. Its description is the subject of this paper. The TC's FSS includes a computer network equipped with a software connected to the specialized program DATAPATH supplied for Cernavoda FSS by the FSS provider, delivered by L-3/ MAPPS. An alternative to DATAPATH Communication of the L 3/MAPPS Simulation System, developed by Cernavoda Full Scope Simulator Staff, was presented in the previous edition of the symposium (see the SIEN 2007 paper). This original solution is now already applied in order to connect to simulation process Data Acquisition Systems DAS1 and DAS2, two new systems already installed in the real MCR but not included by the Cernavoda FSS initial design. Communication between simulation software and DAS1 and DAS2, considered to be simple receivers of simulated data both as much alike as the two DASs from real plant, is performed in parallel with DATAPATH in a safe mode and without affecting simulation process. This paperwork presents the above mentioned application of this communication solution, developed by the Cernavoda NPP Full Scope Simulator Staff with details about the hardware/software solutions and their performance, training impact, cost and benefits. (authors)

  12. MATLAB Simulation of Photovoltaic and Photovoltaic/Thermal Systems Performance

    Science.gov (United States)

    Nasir, Farah H. M.; Husaini, Yusnira

    2018-03-01

    The efficiency of the photovoltaic reduces when the photovoltaic cell temperature increased due to solar irradiance. One solution is come up with the cooling system photovoltaic system. This combination is forming the photovoltaic-thermal (PV/T) system. Not only will it generate electricity also heat at the same time. The aim of this research is to focus on the modeling and simulation of photovoltaic (PV) and photovoltaic-thermal (PV/T) electrical performance by using single-diode equivalent circuit model. Both PV and PV/T models are developed in Matlab/Simulink. By providing the cooling system in PV/T, the efficiency of the system can be increased by decreasing the PV cell temperature. The maximum thermal, electrical and total efficiency values of PV/T in the present research are 35.18%, 15.56% and 50.74% at solar irradiance of 400 W/m2, mass flow rate of 0.05kgs-1 and inlet temperature of 25 °C respectively has been obtained. The photovoltaic-thermal shows that the higher efficiency performance compared to the photovoltaic system.

  13. Equipment and performance upgrade of compact nuclear simulator

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Chang; Kwon, Kee Choon; Lee, Dong Young; Cha, Kyung Ho; Park, Won Man; Song, Soon Ja; Lee, Jung Woon; Oh, In Seok; Moon, Byung Sou; Ham, Chang Shik; Seh, Kyung Won; Joo, Young Chang; Lee, Eui Jin

    1999-12-01

    We developed techniques for upgrading nuclear power plant simulators that lost some function due to aging and obsolescence of parts. This project will provide a guidance for resolving the problems with aged simulators. We transplanted the simulation code operated in Macro-VAX II into the HP workstation with operating system version 10.20. If further research is proceeded, it will be possible to build simulator system on PCs. (author)

  14. PreSurgMapp: a MATLAB Toolbox for Presurgical Mapping of Eloquent Functional Areas Based on Task-Related and Resting-State Functional MRI.

    Science.gov (United States)

    Huang, Huiyuan; Ding, Zhongxiang; Mao, Dewang; Yuan, Jianhua; Zhu, Fangmei; Chen, Shuda; Xu, Yan; Lou, Lin; Feng, Xiaoyan; Qi, Le; Qiu, Wusi; Zhang, Han; Zang, Yu-Feng

    2016-10-01

    The main goal of brain tumor surgery is to maximize tumor resection while minimizing the risk of irreversible postoperative functional sequelae. Eloquent functional areas should be delineated preoperatively, particularly for patients with tumors near eloquent areas. Functional magnetic resonance imaging (fMRI) is a noninvasive technique that demonstrates great promise for presurgical planning. However, specialized data processing toolkits for presurgical planning remain lacking. Based on several functions in open-source software such as Statistical Parametric Mapping (SPM), Resting-State fMRI Data Analysis Toolkit (REST), Data Processing Assistant for Resting-State fMRI (DPARSF) and Multiple Independent Component Analysis (MICA), here, we introduce an open-source MATLAB toolbox named PreSurgMapp. This toolbox can reveal eloquent areas using comprehensive methods and various complementary fMRI modalities. For example, PreSurgMapp supports both model-based (general linear model, GLM, and seed correlation) and data-driven (independent component analysis, ICA) methods and processes both task-based and resting-state fMRI data. PreSurgMapp is designed for highly automatic and individualized functional mapping with a user-friendly graphical user interface (GUI) for time-saving pipeline processing. For example, sensorimotor and language-related components can be automatically identified without human input interference using an effective, accurate component identification algorithm using discriminability index. All the results generated can be further evaluated and compared by neuro-radiologists or neurosurgeons. This software has substantial value for clinical neuro-radiology and neuro-oncology, including application to patients with low- and high-grade brain tumors and those with epilepsy foci in the dominant language hemisphere who are planning to undergo a temporal lobectomy.

  15. Efficient performance simulation of class D amplifier output stages

    DEFF Research Database (Denmark)

    Nyboe, Flemming; Risbo, Lars; Andreani, Pietro

    2005-01-01

    Straightforward simulation of amplifier distortion involves transient simulation of operation on a sine wave input signal, and a subsequent FFT of the output voltage. This approach is very slow on class D amplifiers, since the switching behavior forces simulation time steps that are many orders...... of magnitude smaller than the duration of one period of an audio sine wave. This work presents a method of simulating the amplifier transfer characteristic using a minimum amount of simulation time, and then deriving THD from the results....

  16. Insights into earthquake hazard map performance from shaking history simulations

    Science.gov (United States)

    Stein, S.; Vanneste, K.; Camelbeeck, T.; Vleminckx, B.

    2017-12-01

    Why recent large earthquakes caused shaking stronger than predicted by earthquake hazard maps is under debate. This issue has two parts. Verification involves how well maps implement probabilistic seismic hazard analysis (PSHA) ("have we built the map right?"). Validation asks how well maps forecast shaking ("have we built the right map?"). We explore how well a map can ideally perform by simulating an area's shaking history and comparing "observed" shaking to that predicted by a map generated for the same parameters. The simulations yield shaking distributions whose mean is consistent with the map, but individual shaking histories show large scatter. Infrequent large earthquakes cause shaking much stronger than mapped, as observed. Hence, PSHA seems internally consistent and can be regarded as verified. Validation is harder because an earthquake history can yield shaking higher or lower than that predicted while being consistent with the hazard map. The scatter decreases for longer observation times because the largest earthquakes and resulting shaking are increasingly likely to have occurred. For the same reason, scatter is much less for the more active plate boundary than for a continental interior. For a continental interior, where the mapped hazard is low, even an M4 event produces exceedances at some sites. Larger earthquakes produce exceedances at more sites. Thus many exceedances result from small earthquakes, but infrequent large ones may cause very large exceedances. However, for a plate boundary, an M6 event produces exceedance at only a few sites, and an M7 produces them in a larger, but still relatively small, portion of the study area. As reality gives only one history, and a real map involves assumptions about more complicated source geometries and occurrence rates, which are unlikely to be exactly correct and thus will contribute additional scatter, it is hard to assess whether misfit between actual shaking and a map — notably higher

  17. Simulations of backgate sandwich nanowire MOSFETs with improved device performance

    International Nuclear Information System (INIS)

    Zhao Hengliang; Zhu Huilong; Zhong Jian; Ma Xiaolong; Wei Xing; Zhao Chao; Chen Dapeng; Ye Tianchun

    2014-01-01

    We propose a novel backgate sandwich nanowire MOSFET (SNFET), which offers the advantages of ETSOI (dynamic backgate voltage controllability) and nanowire FETs (good short channel effect). A backgate is used for threshold voltage (V t ) control of the SNFET. Compared with a backgate FinFET with a punch-through stop layer (PTSL), the SNFET possesses improved device performance. 3D device simulations indicate that the SNFET has a three times larger overdrive current, a ∼75% smaller off leakage current, and reduced subthreshold swing (SS) and DIBL than those of a backgate FinFET when the nanowire (NW) and the fin are of equal width. A new process flow to fabricate the backgate SNFET is also proposed in this work. Our analytical model suggests that V t control by the backgate can be attributed to the capacitances formed by the frontgate, NW, and backgate. The SNFET devices are compatible with the latest state-of-the-art high-k/metal gate CMOS technology with the unique capability of independent backgate control for nFETs and pFETs, which is promising for sub-22 nm scaling down. (semiconductor devices)

  18. Equipment and performance upgrade of compact nuclear simulator

    International Nuclear Information System (INIS)

    Park, Jae Chang; Kwon, Kee Choon; Cha, Hyung Ho; Park, Won Man; Song, Soon Ja; Seh, Kyung Won; Joo, Young Chang

    1998-12-01

    In this project, the techniques to upgrade obsolescent nuclear power plant simulation were developed: the simulation code operated in Macro-VAX II has been transplanted to the HP workstation: commercial equipment PLC was adopted for the interface system: the protection logic was developed in the prototype level: and the display system was strengthened. These techniques can be directly used to upgrade other obsolescent simulators

  19. Equipment and performance upgrade of compact nuclear simulator

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Chang; Kwon, Kee Choon; Cha, Hyung Ho; Park, Won Man; Song, Soon Ja; Seh, Kyung Won; Joo, Young Chang

    1998-12-01

    In this project, the techniques to upgrade obsolescent nuclear power plant simulation were developed: the simulation code operated in Macro-VAX II has been transplanted to the HP workstation: commercial equipment PLC was adopted for the interface system: the protection logic was developed in the prototype level: and the display system was strengthened. These techniques can be directly used to upgrade other obsolescent simulators.

  20. Improving operator training and performance through simulator observations

    International Nuclear Information System (INIS)

    Flynn, J.P.

    1987-01-01

    This paper describes the methods and results of INPO observations of simulator training for licensed operators. It discusses the history of the observation program to the present. Effective methods for conducting and documenting simulator observations are discussed. The methods used to analyze the observations is also discussed. The major conclusion of the analysis is that opportunities exist for improvement in the use of emergency operating procedures. Teamwork, communication, and simulator instructor skills are also areas where improvement could be made

  1. An Efficient WSN Simulator for GPU-Based Node Performance

    OpenAIRE

    Kang, An Na; Kim, Hyun-Woo; Barolli, Leonard; Jeong, Young-Sik

    2013-01-01

    In wireless sensor network, when these sensors are wrongly placed in an observation region, they can quickly run out of batteries or be disconnected. These incidents may result in huge losses in terms of sensing data from numerous sensors and their costs. For this reason, a number of simulators have been developed as tools for effective design and verification before the actual arrangement of sensors. While a number of simulators have been developed, simulation results can be fairly limited a...

  2. The Effects of Interdisciplinary Instruction on Simulation Performance.

    Science.gov (United States)

    Clark, Robert A.; Gjerde, Kathy A. Paulson; Skinner, Deborah

    2003-01-01

    Examines implications of specific subject matter intervention by faculty members in economics and marketing on the choices made by students and the consequences of those choices in an online finance simulation. Findings, although mixed, suggest that interdisciplinary intervention in an online finance simulation has the potential to improve the…

  3. The effects of bedrest on crew performance during simulated shuttle reentry. Volume 2: Control task performance

    Science.gov (United States)

    Jex, H. R.; Peters, R. A.; Dimarco, R. J.; Allen, R. W.

    1974-01-01

    A simplified space shuttle reentry simulation performed on the NASA Ames Research Center Centrifuge is described. Anticipating potentially deleterious effects of physiological deconditioning from orbital living (simulated here by 10 days of enforced bedrest) upon a shuttle pilot's ability to manually control his aircraft (should that be necessary in an emergency) a comprehensive battery of measurements was made roughly every 1/2 minute on eight military pilot subjects, over two 20-minute reentry Gz vs. time profiles, one peaking at 2 Gz and the other at 3 Gz. Alternate runs were made without and with g-suits to test the help or interference offered by such protective devices to manual control performance. A very demanding two-axis control task was employed, with a subcritical instability in the pitch axis to force a high attentional demand and a severe loss-of-control penalty. The results show that pilots experienced in high Gz flying can easily handle the shuttle manual control task during 2 Gz or 3 Gz reentry profiles, provided the degree of physiological deconditioning is no more than induced by these 10 days of enforced bedrest.

  4. Driving simulator sickness: Impact on driving performance, influence of blood alcohol concentration, and effect of repeated simulator exposures.

    Science.gov (United States)

    Helland, Arne; Lydersen, Stian; Lervåg, Lone-Eirin; Jenssen, Gunnar D; Mørland, Jørg; Slørdal, Lars

    2016-09-01

    Simulator sickness is a major obstacle to the use of driving simulators for research, training and driver assessment purposes. The purpose of the present study was to investigate the possible influence of simulator sickness on driving performance measures such as standard deviation of lateral position (SDLP), and the effect of alcohol or repeated simulator exposure on the degree of simulator sickness. Twenty healthy male volunteers underwent three simulated driving trials of 1h's duration with a curvy rural road scenario, and rated their degree of simulator sickness after each trial. Subjects drove sober and with blood alcohol concentrations (BAC) of approx. 0.5g/L and 0.9g/L in a randomized order. Simulator sickness score (SSS) did not influence the primary outcome measure SDLP. Higher SSS significantly predicted lower average speed and frequency of steering wheel reversals. These effects seemed to be mitigated by alcohol. Higher BAC significantly predicted lower SSS, suggesting that alcohol inebriation alleviates simulator sickness. The negative relation between the number of previous exposures to the simulator and SSS was not statistically significant, but is consistent with habituation to the sickness-inducing effects, as shown in other studies. Overall, the results suggest no influence of simulator sickness on SDLP or several other driving performance measures. However, simulator sickness seems to cause test subjects to drive more carefully, with lower average speed and fewer steering wheel reversals, hampering the interpretation of these outcomes as measures of driving impairment and safety. BAC and repeated simulator exposures may act as confounding variables by influencing the degree of simulator sickness in experimental studies. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. Validation and computing and performance studies for the ATLAS simulation

    CERN Document Server

    Marshall, Z; The ATLAS collaboration

    2009-01-01

    We present the validation of the ATLAS simulation software pro ject. Software development is controlled by nightly builds and several levels of automatic tests to ensure stability. Computing validation, including CPU time, memory, and disk space required per event, is benchmarked for all software releases. Several different physics processes and event types are checked to thoroughly test all aspects of the detector simulation. The robustness of the simulation software is demonstrated by the production of 500 million events on the World-wide LHC Computing Grid in the last year.

  6. Optimized Parallel Discrete Event Simulation (PDES) for High Performance Computing (HPC) Clusters

    National Research Council Canada - National Science Library

    Abu-Ghazaleh, Nael

    2005-01-01

    The aim of this project was to study the communication subsystem performance of state of the art optimistic simulator Synchronous Parallel Environment for Emulation and Discrete-Event Simulation (SPEEDES...

  7. High-Performance Modeling of Carbon Dioxide Sequestration by Coupling Reservoir Simulation and Molecular Dynamics

    KAUST Repository

    Bao, Kai; Yan, Mi; Allen, Rebecca; Salama, Amgad; Lu, Ligang; Jordan, Kirk E.; Sun, Shuyu; Keyes, David E.

    2015-01-01

    The present work describes a parallel computational framework for carbon dioxide (CO2) sequestration simulation by coupling reservoir simulation and molecular dynamics (MD) on massively parallel high-performance-computing (HPC) systems

  8. A Comparison of Robotic Simulation Performance on Basic Virtual Reality Skills: Simulator Subjective Versus Objective Assessment Tools.

    Science.gov (United States)

    Dubin, Ariel K; Smith, Roger; Julian, Danielle; Tanaka, Alyssa; Mattingly, Patricia

    To answer the question of whether there is a difference between robotic virtual reality simulator performance assessment and validated human reviewers. Current surgical education relies heavily on simulation. Several assessment tools are available to the trainee, including the actual robotic simulator assessment metrics and the Global Evaluative Assessment of Robotic Skills (GEARS) metrics, both of which have been independently validated. GEARS is a rating scale through which human evaluators can score trainees' performances on 6 domains: depth perception, bimanual dexterity, efficiency, force sensitivity, autonomy, and robotic control. Each domain is scored on a 5-point Likert scale with anchors. We used 2 common robotic simulators, the dV-Trainer (dVT; Mimic Technologies Inc., Seattle, WA) and the da Vinci Skills Simulator (dVSS; Intuitive Surgical, Sunnyvale, CA), to compare the performance metrics of robotic surgical simulators with the GEARS for a basic robotic task on each simulator. A prospective single-blinded randomized study. A surgical education and training center. Surgeons and surgeons in training. Demographic information was collected including sex, age, level of training, specialty, and previous surgical and simulator experience. Subjects performed 2 trials of ring and rail 1 (RR1) on each of the 2 simulators (dVSS and dVT) after undergoing randomization and warm-up exercises. The second RR1 trial simulator performance was recorded, and the deidentified videos were sent to human reviewers using GEARS. Eight different simulator assessment metrics were identified and paired with a similar performance metric in the GEARS tool. The GEARS evaluation scores and simulator assessment scores were paired and a Spearman rho calculated for their level of correlation. Seventy-four subjects were enrolled in this randomized study with 9 subjects excluded for missing or incomplete data. There was a strong correlation between the GEARS score and the simulator metric

  9. Methodology for Evaluating the Simulator Flight Performance of Pilots

    National Research Council Canada - National Science Library

    Smith, Jennifer

    2004-01-01

    The type of research that investigates operational tasks such as flying an aircraft or flight simulator is extremely useful to the Air Force's operational community because the results apply directly...

  10. Numerical simulations for active tectonic processes: increasing interoperability and performance

    Science.gov (United States)

    Donnellan, A.; Fox, G.; Rundle, J.; McLeod, D.; Tullis, T.; Grant, L.

    2002-01-01

    The objective of this project is to produce a system to fully model earthquake-related data. This task develops simulation and analysis tools to study the physics of earthquakes using state-of-the-art modeling.

  11. Performance of space charge simulations using High Performance Computing (HPC) cluster

    CERN Document Server

    Bartosik, Hannes; CERN. Geneva. ATS Department

    2017-01-01

    In 2016 a collaboration agreement between CERN and Istituto Nazionale di Fisica Nucleare (INFN) through its Centro Nazionale Analisi Fotogrammi (CNAF, Bologna) was signed [1], which foresaw the purchase and installation of a cluster of 20 nodes with 32 cores each, connected with InfiniBand, at CNAF for the use of CERN members to develop parallelized codes as well as conduct massive simulation campaigns with the already available parallelized tools. As outlined in [1], after the installation and the set up of the first 12 nodes, the green light to proceed with the procurement and installation of the next 8 nodes can be given only after successfully passing an acceptance test based on two specific benchmark runs. This condition is necessary to consider the first batch of the cluster operational and complying with the desired performance specifications. In this brief note, we report the results of the above mentioned acceptance test.

  12. Performance analyses of naval ships based on engineering level of simulation at the initial design stage

    Directory of Open Access Journals (Sweden)

    Dong-Hoon Jeong

    2017-07-01

    Full Text Available Naval ships are assigned many and varied missions. Their performance is critical for mission success, and depends on the specifications of the components. This is why performance analyses of naval ships are required at the initial design stage. Since the design and construction of naval ships take a very long time and incurs a huge cost, Modeling and Simulation (M & S is an effective method for performance analyses. Thus in this study, a simulation core is proposed to analyze the performance of naval ships considering their specifications. This simulation core can perform the engineering level of simulations, considering the mathematical models for naval ships, such as maneuvering equations and passive sonar equations. Also, the simulation models of the simulation core follow Discrete EVent system Specification (DEVS and Discrete Time System Specification (DTSS formalisms, so that simulations can progress over discrete events and discrete times. In addition, applying DEVS and DTSS formalisms makes the structure of simulation models flexible and reusable. To verify the applicability of this simulation core, such a simulation core was applied to simulations for the performance analyses of a submarine in an Anti-SUrface Warfare (ASUW mission. These simulations were composed of two scenarios. The first scenario of submarine diving carried out maneuvering performance analysis by analyzing the pitch angle variation and depth variation of the submarine over time. The second scenario of submarine detection carried out detection performance analysis by analyzing how well the sonar of the submarine resolves adjacent targets. The results of these simulations ensure that the simulation core of this study could be applied to the performance analyses of naval ships considering their specifications.

  13. Framework for Architecture Trade Study Using MBSE and Performance Simulation

    Science.gov (United States)

    Ryan, Jessica; Sarkani, Shahram; Mazzuchim, Thomas

    2012-01-01

    Increasing complexity in modern systems as well as cost and schedule constraints require a new paradigm of system engineering to fulfill stakeholder needs. Challenges facing efficient trade studies include poor tool interoperability, lack of simulation coordination (design parameters) and requirements flowdown. A recent trend toward Model Based System Engineering (MBSE) includes flexible architecture definition, program documentation, requirements traceability and system engineering reuse. As a new domain MBSE still lacks governing standards and commonly accepted frameworks. This paper proposes a framework for efficient architecture definition using MBSE in conjunction with Domain Specific simulation to evaluate trade studies. A general framework is provided followed with a specific example including a method for designing a trade study, defining candidate architectures, planning simulations to fulfill requirements and finally a weighted decision analysis to optimize system objectives.

  14. The simulation research for the dynamic performance of integrated PWR

    International Nuclear Information System (INIS)

    Yuan Jiandong; Xia Guoqing; Fu Mingyu

    2005-01-01

    The mathematical model of the reactor core of integrated PWR has been studied and simplified properly. With the lumped parameter method, authors have established the mathematical model of the reactor core, including the neutron dynamic equation, the feedback reactivities model and the thermo-hydraulic model of the reactor. Based on the above equations and models, the incremental transfer functions of the reactor core model have been built. By simulation experimentation, authors have compared the dynamic characteristics of the integrated PWR with the traditional dispersed PWR. The simulation results show that the mathematical models and equations are correct. (authors)

  15. Simulation of shear and turbulence impact on wind turbine performance

    DEFF Research Database (Denmark)

    Wagner, Rozenn; Courtney, Michael; Larsen, Torben J.

    Aerodynamic simulations (HAWC2Aero) were used to investigate the influence of the speed shear, the direction shear and the turbulence intensity on the power output of a multi-megawatt turbine. First simulation cases with laminar flow and power law wind speed profiles were compared to the case...... of a uniform inflow. Secondly, a similar analysis was done for cases with direction shear. In each case, we derived a standard power curve (function of the wind speed at hub height) and power curves obtained with various definitions of equivalent wind speed in order to reduce the scatter due to shear. Thirdly...

  16. 20th and 21st Joint Workshop on Sustained Simulation Performance

    CERN Document Server

    Bez, Wolfgang; Focht, Erich; Kobayashi, Hiroaki; Qi, Jiaxing; Roller, Sabine

    2015-01-01

    The book presents the state of the art in high-performance computing and simulation on modern supercomputer architectures. It covers trends in hardware and software development in general, and the future of high-performance systems and heterogeneous architectures specifically. The application contributions cover computational fluid dynamics, material science, medical applications and climate research. Innovative fields like coupled multi-physics or multi-scale simulations are also discussed. All papers were chosen from presentations given at the 20th Workshop on Sustained Simulation Performance in December 2014 at the HLRS, University of Stuttgart, Germany, and the subsequent Workshop on Sustained Simulation Performance at Tohoku University in February 2015.  .

  17. Hot and Hypoxic Environments Inhibit Simulated Soccer Performance and Exacerbate Performance Decrements When Combined

    Science.gov (United States)

    Aldous, Jeffrey W. F.; Chrismas, Bryna C. R.; Akubat, Ibrahim; Dascombe, Ben; Abt, Grant; Taylor, Lee

    2016-01-01

    The effects of heat and/or hypoxia have been well-documented in match-play data. However, large match-to-match variation for key physical performance measures makes environmental inferences difficult to ascertain from soccer match-play. Therefore, the present study aims to investigate the hot (HOT), hypoxic (HYP), and hot-hypoxic (HH) mediated-decrements during a non-motorized treadmill based soccer-specific simulation. Twelve male University soccer players completed three familiarization sessions and four randomized crossover experimental trials of the intermittent Soccer Performance Test (iSPT) in normoxic-temperate (CON: 18°C 50% rH), HOT (30°C; 50% rH), HYP (1000 m; 18°C 50% rH), and HH (1000 m; 30°C; 50% rH). Physical performance and its performance decrements, body temperatures (rectal, skin, and estimated muscle temperature), heart rate (HR), arterial blood oxygen saturation (SaO2), perceived exertion, thermal sensation (TS), body mass changes, blood lactate, and plasma volume were all measured. Performance decrements were similar in HOT and HYP [Total Distance (−4%), High-speed distance (~−8%), and variable run distance (~−12%) covered] and exacerbated in HH [total distance (−9%), high-speed distance (−15%), and variable run distance (−15%)] compared to CON. Peak sprint speed, was 4% greater in HOT compared with CON and HYP and 7% greater in HH. Sprint distance covered was unchanged (p > 0.05) in HOT and HYP and only decreased in HH (−8%) compared with CON. Body mass (−2%), temperatures (+2–5%), and TS (+18%) were altered in HOT. Furthermore, SaO2 (−8%) and HR (+3%) were changed in HYP. Similar changes in body mass and temperatures, HR, TS, and SaO2 were evident in HH to HOT and HYP, however, blood lactate (p physical performance during iSPT. Future interventions should address the increases in TS and body temperatures, to attenuate these decrements on soccer performance. PMID:26793122

  18. Numerical Simulation and Optimization of Performances of a Solar ...

    African Journals Online (AJOL)

    This article has as an aim the study and the simulation of the photovoltaic cells containing CdTe materials, contributing to the development of renewable energies, and able to feed from the houses, the shelters as well as photovoltaic stations… etc. CdTe is a semiconductor having a structure of bands with an indirect gap of ...

  19. Flow Simulation and Performance Prediction of Centrifugal Pumps ...

    African Journals Online (AJOL)

    With the aid of computational fluid dynamics, the complex internal flows in water pump impellers can be well predicted, thus facilitating the product development process of pumps. In this paper a commercial CFD code was used to solve the governing equations of the flow field. A 2-D simulation of turbulent fluid flow is ...

  20. Texas cracking performance prediction, simulation, and binder recommendation.

    Science.gov (United States)

    2014-10-01

    Recent studies show some mixes with softer binders used outside of Texas (e.g., Minnesotas Cold Weather Road Research Facility mixes) have both good rutting and cracking performance. However, the current binder performance grading (PG) system fail...

  1. Performance Variables and Professional Experience in Simulated Laparoscopy: A Two-Group Learning Curve Study

    NARCIS (Netherlands)

    Luursema, J.M.; Rovers, Maroeska M.; Groenier, Marleen; van Goor, Harry

    2014-01-01

    Objective Virtual reality simulators are increasingly used in laparoscopy training. Such simulators allow objective assessment of performance. However, both low-level variables and overall scores generated by the simulator can be hard to interpret. We present a method to generate intermediate

  2. Performance variables and professional experience in simulated laparoscopy: a two-group learning curve study

    NARCIS (Netherlands)

    Luursema, J.M.; Rovers, M.M.; Groenier, M.; Goor, H. van

    2014-01-01

    OBJECTIVE: Virtual reality simulators are increasingly used in laparoscopy training. Such simulators allow objective assessment of performance. However, both low-level variables and overall scores generated by the simulator can be hard to interpret. We present a method to generate intermediate

  3. An Advanced, Interactive, High-Performance Liquid Chromatography Simulator and Instructor Resources

    Science.gov (United States)

    Boswell, Paul G.; Stoll, Dwight R.; Carr, Peter W.; Nagel, Megan L.; Vitha, Mark F.; Mabbott, Gary A.

    2013-01-01

    High-performance liquid chromatography (HPLC) simulation software has long been recognized as an effective educational tool, yet many of the existing HPLC simulators are either too expensive, outdated, or lack many important features necessary to make them widely useful for educational purposes. Here, a free, open-source HPLC simulator is…

  4. Critical thinking skills in nursing students: comparison of simulation-based performance with metrics

    Science.gov (United States)

    Fero, Laura J.; O’Donnell, John M.; Zullo, Thomas G.; Dabbs, Annette DeVito; Kitutu, Julius; Samosky, Joseph T.; Hoffman, Leslie A.

    2018-01-01

    Aim This paper is a report of an examination of the relationship between metrics of critical thinking skills and performance in simulated clinical scenarios. Background Paper and pencil assessments are commonly used to assess critical thinking but may not reflect simulated performance. Methods In 2007, a convenience sample of 36 nursing students participated in measurement of critical thinking skills and simulation-based performance using videotaped vignettes, high-fidelity human simulation, the California Critical Thinking Disposition Inventory and California Critical Thinking Skills Test. Simulation- based performance was rated as ‘meeting’ or ‘not meeting’ overall expectations. Test scores were categorized as strong, average, or weak. Results Most (75·0%) students did not meet overall performance expectations using videotaped vignettes or high-fidelity human simulation; most difficulty related to problem recognition and reporting findings to the physician. There was no difference between overall performance based on method of assessment (P = 0·277). More students met subcategory expectations for initiating nursing interventions (P ≤ 0·001) using high-fidelity human simulation. The relationship between video-taped vignette performance and critical thinking disposition or skills scores was not statistically significant, except for problem recognition and overall critical thinking skills scores (Cramer’s V = 0·444, P = 0·029). There was a statistically significant relationship between overall high-fidelity human simulation performance and overall critical thinking disposition scores (Cramer’s V = 0·413, P = 0·047). Conclusion Students’ performance reflected difficulty meeting expectations in simulated clinical scenarios. High-fidelity human simulation performance appeared to approximate scores on metrics of critical thinking best. Further research is needed to determine if simulation-based performance correlates with critical thinking skills

  5. Critical thinking skills in nursing students: comparison of simulation-based performance with metrics.

    Science.gov (United States)

    Fero, Laura J; O'Donnell, John M; Zullo, Thomas G; Dabbs, Annette DeVito; Kitutu, Julius; Samosky, Joseph T; Hoffman, Leslie A

    2010-10-01

    This paper is a report of an examination of the relationship between metrics of critical thinking skills and performance in simulated clinical scenarios. Paper and pencil assessments are commonly used to assess critical thinking but may not reflect simulated performance. In 2007, a convenience sample of 36 nursing students participated in measurement of critical thinking skills and simulation-based performance using videotaped vignettes, high-fidelity human simulation, the California Critical Thinking Disposition Inventory and California Critical Thinking Skills Test. Simulation-based performance was rated as 'meeting' or 'not meeting' overall expectations. Test scores were categorized as strong, average, or weak. Most (75.0%) students did not meet overall performance expectations using videotaped vignettes or high-fidelity human simulation; most difficulty related to problem recognition and reporting findings to the physician. There was no difference between overall performance based on method of assessment (P = 0.277). More students met subcategory expectations for initiating nursing interventions (P ≤ 0.001) using high-fidelity human simulation. The relationship between videotaped vignette performance and critical thinking disposition or skills scores was not statistically significant, except for problem recognition and overall critical thinking skills scores (Cramer's V = 0.444, P = 0.029). There was a statistically significant relationship between overall high-fidelity human simulation performance and overall critical thinking disposition scores (Cramer's V = 0.413, P = 0.047). Students' performance reflected difficulty meeting expectations in simulated clinical scenarios. High-fidelity human simulation performance appeared to approximate scores on metrics of critical thinking best. Further research is needed to determine if simulation-based performance correlates with critical thinking skills in the clinical setting. © 2010 The Authors. Journal of Advanced

  6. Radiotracer experiments and CFD simulation for industrial hydrocyclone performance

    International Nuclear Information System (INIS)

    Stegowski, Z.; Nowak, E.

    2007-01-01

    Hydrocyclone is a device for solid concentration or selection of solid particles from a liquid-solid mixture. It is widely used in the mineral industry for selection of solid particles from a few to a few hundred micrometers. This paper presents a radiotracer experiment and computational simulation of selection of solid particles in a hydrocyclone of Φ-500 μm, which is used in the industrial copper ore concentration process. The simulation, based on computational fluid dynamics (CFD) techniques, allowed obtaining the velocity and concentration distribution for a real mixture flowing in the hydrocyclone. The mixture was composed of water and nine solid phases of different grain sizes. Finally, the selection curve of solid grains was obtained and compared with the experimental radiotracer results. (author)

  7. Contrasting the capabilities of building energy performance simulation programs

    Energy Technology Data Exchange (ETDEWEB)

    Crawley, Drury B. [US Department of Energy, Washington, DC (United States); Hand, Jon W. [University of Strathclyde, Glasgow, Scotland (United Kingdom). Energy Systems Research Unit; Kummert, Michael [University of Wisconsin-Madison (United States). Solar Energy Laboratory; Griffith, Brent T. [National Renewable Energy Laboratory, Golden, CO (United States)

    2008-04-15

    For the past 50 years, a wide variety of building energy simulation programs have been developed, enhanced and are in use throughout the building energy community. This paper is an overview of a report, which provides up-to-date comparison of the features and capabilities of twenty major building energy simulation programs. The comparison is based on information provided by the program developers in the following categories: general modeling features; zone loads; building envelope and daylighting and solar; infiltration, ventilation and multizone airflow; renewable energy systems; electrical systems and equipment; HVAC systems; HVAC equipment; environmental emissions; economic evaluation; climate data availability, results reporting; validation; and user interface, links to other programs, and availability. (author)

  8. OPNET Modeler simulations of performance for multi nodes wireless systems

    Directory of Open Access Journals (Sweden)

    Krupanek Beata

    2016-01-01

    Full Text Available Paper presents a study under the Quality of Service in modern wireless sensor networks. Such a networks are characterized by small amount of data transmitted in fixed periods. Very often this data must by transmitted in real time so data transmission delays should be well known. This article shows multimode network simulated in packet OPNET Modeler. Also nowadays the quality of services is very important especially in multi-nodes systems such a home automation or measurement systems.

  9. Properties of nanoparticles affecting simulation of fibrous gas filter performance

    International Nuclear Information System (INIS)

    Tronville, Paolo; Rivers, Richard

    2015-01-01

    Computational Fluid Dynamics (CFD) codes allow detailed simulation of the flow of gases through fibrous filter media. When the pattern of gas flow between fibers has been established, simulated particles of any desired size can be “injected” into the entering gas stream, and their paths under the influence of aerodynamic drag, Brownian motion and electrostatic forces tracked. Particles either collide with a fiber, or pass through the entire filter medium. They may bounce off the fiber surface, or adhere firmly to the surface or to particles previously captured. Simulated injection of many particles at random locations in the entering stream allows the average probability of capture to be calculated. Many particle properties must be available as parameters for the equations defining the forces on particles in the gas stream, at the moment of contact with a fiber, and after contact. Accurate values for all properties are needed, not only for predicting particle capture in actual service, but also to validate models for media geometries and computational procedures used in CFD. We present a survey of existing literature on the properties influencing nanoparticle dynamics and adhesion. (paper)

  10. SIMULATED PERFORMANCE OF TIMESCALE METRICS FOR APERIODIC LIGHT CURVES

    Energy Technology Data Exchange (ETDEWEB)

    Findeisen, Krzysztof; Hillenbrand, Lynne [Cahill Center for Astronomy and Astrophysics, California Institute of Technology, MC 249-17, Pasadena, CA 91125 (United States); Cody, Ann Marie, E-mail: krzys@astro.caltech.edu [Spitzer Science Center, California Institute of Technology, MC 314-6, Pasadena, CA 91125 (United States)

    2015-01-10

    Aperiodic variability is a characteristic feature of young stars, massive stars, and active galactic nuclei. With the recent proliferation of time-domain surveys, it is increasingly essential to develop methods to quantify and analyze aperiodic variability. We develop three timescale metrics that have been little used in astronomy—Δm-Δt plots, peak-finding, and Gaussian process regression—and present simulations comparing their effectiveness across a range of aperiodic light curve shapes, characteristic timescales, observing cadences, and signal to noise ratios. We find that Gaussian process regression is easily confused by noise and by irregular sampling, even when the model being fit reflects the process underlying the light curve, but that Δm-Δt plots and peak-finding can coarsely characterize timescales across a broad region of parameter space. We make public the software we used for our simulations, both in the spirit of open research and to allow others to carry out analogous simulations for their own observing programs.

  11. SIMULATED PERFORMANCE OF TIMESCALE METRICS FOR APERIODIC LIGHT CURVES

    International Nuclear Information System (INIS)

    Findeisen, Krzysztof; Hillenbrand, Lynne; Cody, Ann Marie

    2015-01-01

    Aperiodic variability is a characteristic feature of young stars, massive stars, and active galactic nuclei. With the recent proliferation of time-domain surveys, it is increasingly essential to develop methods to quantify and analyze aperiodic variability. We develop three timescale metrics that have been little used in astronomy—Δm-Δt plots, peak-finding, and Gaussian process regression—and present simulations comparing their effectiveness across a range of aperiodic light curve shapes, characteristic timescales, observing cadences, and signal to noise ratios. We find that Gaussian process regression is easily confused by noise and by irregular sampling, even when the model being fit reflects the process underlying the light curve, but that Δm-Δt plots and peak-finding can coarsely characterize timescales across a broad region of parameter space. We make public the software we used for our simulations, both in the spirit of open research and to allow others to carry out analogous simulations for their own observing programs

  12. HPC Performance Analysis of a Distributed Information Enterprise Simulation

    National Research Council Canada - National Science Library

    Hanna, James P; Walter, Martin J; Hillman, Robert G

    2004-01-01

    .... The analysis identified several performance limitations and bottlenecks. One critical limitation addressed and eliminated was simultaneously mixing a periodic process model with an event driven model causing rollbacks...

  13. Simulation

    DEFF Research Database (Denmark)

    Gould, Derek A; Chalmers, Nicholas; Johnson, Sheena J

    2012-01-01

    Recognition of the many limitations of traditional apprenticeship training is driving new approaches to learning medical procedural skills. Among simulation technologies and methods available today, computer-based systems are topical and bring the benefits of automated, repeatable, and reliable p...... performance assessments. Human factors research is central to simulator model development that is relevant to real-world imaging-guided interventional tasks and to the credentialing programs in which it would be used....

  14. On the performance of voting systems in spatial voting simulations

    NARCIS (Netherlands)

    Negriu, A.; Piatecki, C.

    2012-01-01

    We study the performance of voting systems in terms of minimizing the overall social disutility of making a collective choice in an univariate voting space with ideological voting and perfect information. In order to obtain a distribution of the performance indicator for each of the 12 systems

  15. Uncertainty and sensitivity analysis in building performance simulation for decision support and design optimization

    NARCIS (Netherlands)

    Hopfe, C.J.

    2009-01-01

    Building performance simulation (BPS) uses computer-based models that cover performance aspects such as energy consumption and thermal comfort in buildings. The uptake of BPS in current building design projects is limited. Although there is a large number of building simulation tools available, the

  16. Achieving informed decision-making for net zero energy buildings design using building performance simulation tools

    NARCIS (Netherlands)

    Attia, S.G.; Gratia, E.; De Herde, A.; Hensen, J.L.M.

    2013-01-01

    Building performance simulation (BPS) is the basis for informed decision-making of Net Zero Energy Buildings (NZEBs) design. This paper aims to investigate the use of building performance simulation tools as a method of informing the design decision of NZEBs. The aim of this study is to evaluate the

  17. Association Between Endovascular Performance in a Simulated Setting and in the Catheterization Laboratory

    DEFF Research Database (Denmark)

    Räder, Sune B E W; Abildgaard, Ulrik; Jørgensen, Erik

    2014-01-01

    performance in the catheterization laboratory is not linear. The novel rating scale for CA (CARS) seems to be a valid proficiency assessment instrument in the catheterization laboratory. Familiarity with the simulator may overestimate proficiency, which means that simulator performance as a predictor...

  18. Performance simulations of catalytic converters during the Federal Test Procedure

    Energy Technology Data Exchange (ETDEWEB)

    Shen, H.; Shamim, T.; Sengupta, S.; Son, S.; Adamczyk, A.A.

    1999-07-01

    A numerical study is carried out to predict the tailpipe emissions and emission conversion efficiencies of unburned hydrocarbon, nitrogen oxide and carbon monoxide flowing through a catalytic converter during the Federal Test Procedure (FTP). The model considers the effect of heat transfer in the catalytic converter, coupled with catalyst chemical kinetics, including an oxygen storage mechanism. The resulting governing equations based on the conservation of mass and energy are solved by a tridiagonal matrix algorithm (TDMA) with a successive line under relaxation method. The numerical scheme for this non-linear problem is found to have good convergence efficiency. The simulation for the complete FTP cycle is accomplished in less than fifteen minutes on a desktop personal computer. A 13-step reaction mechanism plus a nine-step O{sub 2} storage mechanism is used to simulate the chemical kinetics. The energy equations include the heat loss due to conduction and convection plus the energy liberated by chemical reactions. The effect of radiation is assumed to be negligible and is not considered. The results of the numerical model for both the instantaneous and accumulated emissions are found to be in good agreement with experimental measurements. The conversion efficiencies of HC, CO and NO as predicted by the model are found to be within 5% of those dynamic measurements, and calculated results of accumulated HC, CO and NO{sub x} are in fair agreement with experimental measurements. The transient measurements are also used to check the robustness of the numerical model. The model is found to be robust and hence can simulate various operating conditions of engine output to the converter.

  19. Performance simulation in high altitude platforms (HAPs) communications systems

    Science.gov (United States)

    Ulloa-Vásquez, Fernando; Delgado-Penin, J. A.

    2002-07-01

    This paper considers the analysis by simulation of a digital narrowband communication system for an scenario which consists of a High-Altitude aeronautical Platform (HAP) and fixed/mobile terrestrial transceivers. The aeronautical channel is modelled considering geometrical (angle of elevation vs. horizontal distance of the terrestrial reflectors) and statistical arguments and under these circumstances a serial concatenated coded digital transmission is analysed for several hypothesis related to radio-electric coverage areas. The results indicate a good feasibility for the communication system proposed and analysed.

  20. HCIT Contrast Performance Sensitivity Studies: Simulation Versus Experiment

    Science.gov (United States)

    Sidick, Erkin; Shaklan, Stuart; Krist, John; Cady, Eric J.; Kern, Brian; Balasubramanian, Kunjithapatham

    2013-01-01

    Using NASA's High Contrast Imaging Testbed (HCIT) at the Jet Propulsion Laboratory, we have experimentally investigated the sensitivity of dark hole contrast in a Lyot coronagraph for the following factors: 1) Lateral and longitudinal translation of an occulting mask; 2) An opaque spot on the occulting mask; 3) Sizes of the controlled dark hole area. Also, we compared the measured results with simulations obtained using both MACOS (Modeling and Analysis for Controlled Optical Systems) and PROPER optical analysis programs with full three-dimensional near-field diffraction analysis to model HCIT's optical train and coronagraph.

  1. Performance predictions for solar-chemical convertors by computer simulation

    Energy Technology Data Exchange (ETDEWEB)

    Luttmer, J.D.; Trachtenberg, I.

    1985-08-01

    A computer model which simulates the operation of Texas Instruments solar-chemical convertor (SCC) was developed. The model allows optimization of SCC processes, material, and configuration by facilitating decisions on tradeoffs among ease of manufacturing, power conversion efficiency, and cost effectiveness. The model includes various algorithms which define the electrical, electrochemical, and resistance parameters and which describ the operation of the discrete components of the SCC. Results of the model which depict the effect of material and geometric changes on various parameters are presented. The computer-calculated operation is compared with experimentall observed hydrobromic acid electrolysis rates.

  2. Performance Test of Core Protection and Monitoring Algorithm with DLL for SMART Simulator Implementation

    International Nuclear Information System (INIS)

    Koo, Bonseung; Hwang, Daehyun; Kim, Keungkoo

    2014-01-01

    A multi-purpose best-estimate simulator for SMART is being established, which is intended to be used as a tool to evaluate the impacts of design changes on the safety performance, and to improve and/or optimize the operating procedure of SMART. In keeping with these intentions, a real-time model of the digital core protection and monitoring systems was developed and the real-time performance of the models was verified for various simulation scenarios. In this paper, a performance test of the core protection and monitoring algorithm with a DLL file for the SMART simulator implementation was performed. A DLL file of the simulator application code was made and several real-time evaluation tests were conducted for the steady-state and transient conditions with simulated system variables. A performance test of the core protection and monitoring algorithms for the SMART simulator was performed. A DLL file of the simulator version code was made and several real-time evaluation tests were conducted for various scenarios with a DLL file and simulated system variables. The results of all test cases showed good agreement with the reference results and some features caused by algorithm change were properly reflected to the DLL results. Therefore, it was concluded that the SCOPS S SIM and SCOMS S SIM algorithms and calculational capabilities are appropriate for the core protection and monitoring program in the SMART simulator

  3. Lean Supply Chain Planning: A Performance Evaluation through Simulation

    Directory of Open Access Journals (Sweden)

    Rossini Matteo

    2016-01-01

    Full Text Available Nowadays companies look more and more for improving their efficiency to excel in the market. At the same time, the competition has moved from firm level to whole supply chain level. Supply chain are very complex systems and lacks of coordination among their members leads to inefficiency. Supply chain planning task is to improve coordination among supply chain members. Which is the best planning solution to improve efficiency is an open issue. On the other hand, Lean approach is becoming more and more popular among managers. Lean approach is recognize as efficiency engine for production systems, but effects of Lean implementation out of single firm boundaries is not clear. This paper aims at providing a theoretical and practical starting point for Lean implementation in supply chain planning issue. To reach it, a DES simulation model of a three-echelon and multi-product supply chain has been set. Lean management is a very broad topic and this paper focuses on two principles of “pull” and “create the flow”. Kanban system and setup-time and batch-size reductions are implemented in the lean-configured supply chain to apply “pull” and “create the flow” respectively. Lean principles implementations have been analyzed and compared with other supply chain planning policies: EOQ and information sharing (Visibility. Supported by the simulation study, this paper points Lean supply chain planning is a competitive planning policies to increase efficiency.

  4. Monte Carlo simulation of the HEGRA cosmic ray detector performance

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, S. [Universidad Complutense de Madrid (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Arqueros, F. [Universidad Complutense de Madrid (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Fonseca, V. [Universidad Complutense de Madrid (Spain). Dept. de Fisica Atomica, Molecular y Nuclear; Karle, A. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany); Lorenz, E. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany); Plaga, R. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany); Rozanska, M. [Max-Planck-Institut fuer Physik, Foehringer Ring 6, D80805 Munich (Germany)]|[Institute of Nuclear Physics, ul.Kawiory 26a, PL30-055 Cracow (Poland)

    1995-04-21

    Models of the scintillator and wide-angle air Cherenkov (AIROBICC) arrays of the HEGRA experiment are described here. Their response to extensive air showers generated by cosmic rays in the 10 to 1000 TeV range has been assessed using a detailed Monte Carlo simulation of air shower development and associated Cherenkov emission. Protons, {gamma}-rays and oxygen and iron nuclei have been considered as primary particles. For both arrays, the angular resolution as determined from the Monte Carlo simulation is compared with experimental data. Shower size N{sub e} can be reconstructed from the scintillator signals with an error ranging from 10% (N{sub e}=2x10{sup 5}) to 35% (N{sub e}=3x10{sup 3}). The energy threshold of AIROBICC is 14 TeV for primary gammas and 27 TeV for protons and an angular resolution of 0.25 can be obtained. The measurement of the Cherenkov light at 90 m from the shower core provides an accurate determination of primary energy E{sub 0} as far as the nature of the primary particle is known. For gammas an error in the energy prediction ranging from 8% (E{sub 0}=5x10{sup 14} eV) to 15% (E{sub 0}=2x10{sup 13} eV) is achieved. This detector is therefore a powerful tool for {gamma}-ray astronomy. ((orig.)).

  5. Simulation of cloud data security processes and performance

    OpenAIRE

    Chand, K; Ramachandran, M; Kor, AL

    2015-01-01

    In the world of cloud computing, millions of people are using cloud computing for the purpose of business, education and socialization. Examples of cloud applications are: Google Drive for storage, Facebook for social networks, etc. Cloud users use the cloud computing infrastructure thinking that these services are easy and safe to use. However, there are security and performance issues to be addressed. This paper discusses how cloud users and cloud providers address performance and security ...

  6. Proficiency performance benchmarks for removal of simulated brain tumors using a virtual reality simulator NeuroTouch.

    Science.gov (United States)

    AlZhrani, Gmaan; Alotaibi, Fahad; Azarnoush, Hamed; Winkler-Schwartz, Alexander; Sabbagh, Abdulrahman; Bajunaid, Khalid; Lajoie, Susanne P; Del Maestro, Rolando F

    2015-01-01

    Assessment of neurosurgical technical skills involved in the resection of cerebral tumors in operative environments is complex. Educators emphasize the need to develop and use objective and meaningful assessment tools that are reliable and valid for assessing trainees' progress in acquiring surgical skills. The purpose of this study was to develop proficiency performance benchmarks for a newly proposed set of objective measures (metrics) of neurosurgical technical skills performance during simulated brain tumor resection using a new virtual reality simulator (NeuroTouch). Each participant performed the resection of 18 simulated brain tumors of different complexity using the NeuroTouch platform. Surgical performance was computed using Tier 1 and Tier 2 metrics derived from NeuroTouch simulator data consisting of (1) safety metrics, including (a) volume of surrounding simulated normal brain tissue removed, (b) sum of forces utilized, and (c) maximum force applied during tumor resection; (2) quality of operation metric, which involved the percentage of tumor removed; and (3) efficiency metrics, including (a) instrument total tip path lengths and (b) frequency of pedal activation. All studies were conducted in the Neurosurgical Simulation Research Centre, Montreal Neurological Institute and Hospital, McGill University, Montreal, Canada. A total of 33 participants were recruited, including 17 experts (board-certified neurosurgeons) and 16 novices (7 senior and 9 junior neurosurgery residents). The results demonstrated that "expert" neurosurgeons resected less surrounding simulated normal brain tissue and less tumor tissue than residents. These data are consistent with the concept that "experts" focused more on safety of the surgical procedure compared with novices. By analyzing experts' neurosurgical technical skills performance on these different metrics, we were able to establish benchmarks for goal proficiency performance training of neurosurgery residents. This

  7. Caffeine and performance over consecutive days of simulated competition.

    Science.gov (United States)

    Stadheim, Hans Kristian; Spencer, Matthew; Olsen, Raymond; Jensen, Jørgen

    2014-09-01

    Performance improvements after caffeine (CAF) ingestion are well documented when using a 1-d protocol. In numerous competitions such as the Tour de France, Tour de Ski, world championships, and National College Athletic Association championships, athletes compete for several days in a row. To date, no studies have investigated the effects of CAF when competing for consecutive days in a row. This study aimed to investigate the effects of placebo (PLA) and two different CAF doses (3 and 4.5 mg·kg body mass) on performance in a 10-min all-out, cross-country, double poling ergometer test (C-PT) 2 d in a row. Eight highly trained male cross-country skiers (V˙O2max-run, 78.5 ± 1.6 mL·kg·min) participated in the study, which was a randomized, double-blind, PLA-controlled, crossover design. Performance was assessed as distance covered during a 10-min all-out C-PT. Oral ingestion of CAF or PLA was consumed 75 min before the all-out C-PT. Poling distance was improved after CAF ingestions compared with that after PLA on both days. The improvements on day 1 were 4.0% (90% confidence limits, ±3.3) and 4.0% ± 2.9% for both CAF doses, respectively (P performance was associated with increased HR, adrenaline concentration, blood lactate concentration, and V˙O2 consumption after CAF ingestion. Furthermore, performance was elevated despite higher creatine kinase concentration and muscular pain at arrival on day 2 for both CAF doses. Both CAF doses improved performance in the 10-min all-out C-PT compared with PLA over two consecutive days. Therefore, CAF seems useful for athletes competing over consecutive days despite higher muscle damage occurring after enhanced performance on the first day.

  8. Performance Evaluation and Development of Virtual Reality Bike Simulator

    Energy Technology Data Exchange (ETDEWEB)

    Kim, J.Y.; Song, C.G.; Kim, N.G. [Chonbuk National University, Chonju (Korea)

    2002-03-01

    This paper describes a new bike system for the postural balance rehabilitation training. Virtual environment and three dimensional graphic model is designed with CAD tools such as 3D Studio Max and World Up. For the real time bike simulation, the optimized WorldToolKit graphic library is embedded with the dynamic geometry generation method, multi-thread method, and portal generation method. In this experiment, 20 normal adults were tested to investigate the influencing factors of balancing posture. We evaluated the system by measuring the parameters such as path deviation, driving velocity, COP(center of pressure), and average weight shift. Also, we investigated the usefulness of visual feedback information by weight shift. The results showed that continuous visual feedback by weight shift was more effective than no visual feedback in the postural balance control. It is concluded this system might be applied to clinical use as a new postural balance training system. (author). 19 refs., 15 figs., 2 tabs.

  9. A high performance scientific cloud computing environment for materials simulations

    Science.gov (United States)

    Jorissen, K.; Vila, F. D.; Rehr, J. J.

    2012-09-01

    We describe the development of a scientific cloud computing (SCC) platform that offers high performance computation capability. The platform consists of a scientific virtual machine prototype containing a UNIX operating system and several materials science codes, together with essential interface tools (an SCC toolset) that offers functionality comparable to local compute clusters. In particular, our SCC toolset provides automatic creation of virtual clusters for parallel computing, including tools for execution and monitoring performance, as well as efficient I/O utilities that enable seamless connections to and from the cloud. Our SCC platform is optimized for the Amazon Elastic Compute Cloud (EC2). We present benchmarks for prototypical scientific applications and demonstrate performance comparable to local compute clusters. To facilitate code execution and provide user-friendly access, we have also integrated cloud computing capability in a JAVA-based GUI. Our SCC platform may be an alternative to traditional HPC resources for materials science or quantum chemistry applications.

  10. Effects of Simulated Conductive Hearing Loss on Dichotic Listening Performance for Digits.

    Science.gov (United States)

    Niccum, Nancy; And Others

    1987-01-01

    Conductive hearing losses were simulated in 12 subjects aged 19-35 and performance was compared with normal hearing performance. Digit dichotic performance was affected when test intensities were within 8 dB of the "knees" (95 percent correct point) of monotic performance intensity functions, but not when test intensities were 12 dB…

  11. Simulated Evaluation of Drug-Impaired Psychomotor Performance

    OpenAIRE

    Richmond R

    2014-01-01

    The purpose of this placebo-controlled, randomized-crossover study was to evaluate a computer-based divided-attention task as a method for measure impaired human psychomotor performance. The ability of the divided-attention task to detect and differentiate was evaluated using single oral doses of placebo, caffeine and diphenhydramine. Ten healthy men were the subjects of the study. Subject performance on divided-attention was compared with tests of short-term memory and a set of visual analog...

  12. Performance Properties Of Saltstone Produced Using SWPF Simulants

    International Nuclear Information System (INIS)

    Harbour, J.; Edwards, T.

    2010-01-01

    The overwhelming majority of waste to be immobilized at the Saltstone Production Facility will come from the waste stream exiting the Salt Waste Processing Facility (SWPF). These SWPF batches are salt solutions that result from pretreatment of the High Level Waste (HLW) supernate by an Actinide Removal Process followed by Caustic Side Solvent Extraction. The concentration of aluminate within these streams will vary and be determined by (1) the concentration in the incoming salt waste stream, (2) the degree of aluminum leaching from the HLW, (3) the method for introducing the aluminate into the waste stream (continuous or batch) and (4) and any operational or regulatory limitations. The overall Performance Assessment outcome for the Saltstone Disposal Facility will depend significantly on the performance properties of the SWPF Saltstone grouts. This report identifies and quantifies, when possible, those factors that drive the performance properties of the projected SWPF grouts. Previous work has identified aluminate concentration in the salt waste stream as a key factor in determining performance. Consequently, significant variation in the aluminate concentration to a maximum level of 0.65 M was investigated in this report. The SWPF baseline grout is a mix with a 0.60 water to cementitious ratio and a premix composition of 45 wt % slag, 45 wt % fly ash and 10 wt % portland cement. The key factors that drive performance of the SWPF mixes were determined to be (1) the time/temperature profile for curing, (2) water to cementitious materials ratio, (3) aluminate concentration in the waste stream, and (4) wt % slag in the premix. An increase in the curing temperature for mixes with 45 wt % slag resulted in a 2.5 times decrease in Young's modulus. The reduction of Young's modulus measured at 60 C versus 22 C was mitigated by an increase in the aluminate concentration but was still significant. For mixes containing 60 wt % slag, the reduction in Young's modulus between

  13. Distributed dynamic simulations of networked control and building performance applications

    NARCIS (Netherlands)

    Yahiaoui, Azzedine

    2018-01-01

    The use of computer-based automation and control systems for smart sustainable buildings, often so-called Automated Buildings (ABs), has become an effective way to automatically control, optimize, and supervise a wide range of building performance applications over a network while achieving the

  14. Cognitive Performance during a 24-Hour Cold Exposure Survival Simulation

    Directory of Open Access Journals (Sweden)

    Michael J. Taber

    2016-01-01

    Full Text Available Survivor of a ship ground in polar regions may have to wait more than five days before being rescued. Therefore, the purpose of this study was to explore cognitive performance during prolonged cold exposure. Core temperature (Tc and cognitive test battery (CTB performance data were collected from eight participants during 24 hours of cold exposure (7.5°C ambient air temperature. Participants (recruited from those who have regular occupational exposure to cold were instructed that they could freely engage in minimal exercise that was perceived to maintaining a tolerable level of thermal comfort. Despite the active engagement, test conditions were sufficient to significantly decrease Tc after exposure and to eliminate the typical 0.5–1.0°C circadian rise and drop in core temperature throughout a 24 h cycle. Results showed minimal changes in CTB performance regardless of exposure time. Based on the results, it is recommended that survivors who are waiting for rescue should be encouraged to engage in mild physical activity, which could have the benefit of maintaining metabolic heat production, improve motivation, and act as a distractor from cold discomfort. This recommendation should be taken into consideration during future research and when considering guidelines for mandatory survival equipment regarding cognitive performance.

  15. High performance simulation of lattice physics using enhanced transputer arrays

    International Nuclear Information System (INIS)

    Hey, A.J.G.; Jesshope, C.R.; Nicole, D.A.

    1986-01-01

    The authors describe an architecture under construction at Southampton using arrays of communicating transputers with enhanced floating-point capabilities. Performance in the Gigaflop range is expected. Algorithms for taking explicit advantage of this MIMD architecture are discussed using the Occam programming paradigm. (Auth.)

  16. The Effect of Autogenic Training on Self-Efficacy, Anxiety, and Performance on Nursing Student Simulation.

    Science.gov (United States)

    Holland, Brian; Gosselin, Kevin; Mulcahy, Angela

    The increased anxiety experienced by nursing students during simulations can serve as a significant barrier to learning. The use of anxiety-reducing techniques such as autogenic training (AT) can mitigate the negative effects of anxiety and improve the overall learning experience. The investigators in this study sought to understand the effect of AT on student performance and self-efficacy during simulation experiences. The use of AT was an effective technique to decrease anxiety and increase performance among nursing students during nursing simulations. Reducing anxiety during simulations can improve the student learning experience.

  17. Unique Microstructural Changes in the Brain Associated with Urological Chronic Pelvic Pain Syndrome (UCPPS Revealed by Diffusion Tensor MRI, Super-Resolution Track Density Imaging, and Statistical Parameter Mapping: A MAPP Network Neuroimaging Study.

    Directory of Open Access Journals (Sweden)

    Davis Woodworth

    Full Text Available Studies have suggested chronic pain syndromes are associated with neural reorganization in specific regions associated with perception, processing, and integration of pain. Urological chronic pelvic pain syndrome (UCPPS represents a collection of pain syndromes characterized by pelvic pain, namely Chronic Prostatitis/Chronic Pelvic Pain Syndrome (CP/CPPS and Interstitial Cystitis/Painful Bladder Syndrome (IC/PBS, that are both poorly understood in their pathophysiology, and treated ineffectively. We hypothesized patients with UCPPS may have microstructural differences in the brain compared with healthy control subjects (HCs, as well as patients with irritable bowel syndrome (IBS, a common gastrointestinal pain disorder. In the current study we performed population-based voxel-wise DTI and super-resolution track density imaging (TDI in a large, two-center sample of phenotyped patients from the multicenter cohort with UCPPS (N = 45, IBS (N = 39, and HCs (N = 56 as part of the MAPP Research Network. Compared with HCs, UCPPS patients had lower fractional anisotropy (FA, lower generalized anisotropy (GA, lower track density, and higher mean diffusivity (MD in brain regions commonly associated with perception and integration of pain information. Results also showed significant differences in specific anatomical regions in UCPPS patients when compared with IBS patients, consistent with microstructural alterations specific to UCPPS. While IBS patients showed clear sex related differences in FA, MD, GA, and track density consistent with previous reports, few such differences were observed in UCPPS patients. Heat maps illustrating the correlation between specific regions of interest and various pain and urinary symptom scores showed clustering of significant associations along the cortico-basal ganglia-thalamic-cortical loop associated with pain integration, modulation, and perception. Together, results suggest patients with UCPPS have extensive

  18. Performance of three-photon PET imaging: Monte Carlo simulations

    International Nuclear Information System (INIS)

    Kacperski, Krzysztof; Spyrou, Nicholas M

    2005-01-01

    We have recently introduced the idea of making use of three-photon positron annihilations in positron emission tomography. In this paper, the basic characteristics of the three-gamma imaging in PET are studied by means of Monte Carlo simulations and analytical computations. Two typical configurations of human and small animal scanners are considered. Three-photon imaging requires high-energy resolution detectors. Parameters currently attainable by CdZnTe semiconductor detectors, the technology of choice for the future development of radiation imaging, are assumed. Spatial resolution is calculated as a function of detector energy resolution and size, position in the field of view, scanner size and the energies of the three-gamma annihilation photons. Possible ways to improve the spatial resolution obtained for nominal parameters, 1.5 cm and 3.2 mm FWHM for human and small animal scanners, respectively, are indicated. Counting rates of true and random three-photon events for typical human and small animal scanning configurations are assessed. A simple formula for minimum size of lesions detectable in the three-gamma based images is derived. Depending on the contrast and total number of registered counts, lesions of a few mm size for human and sub mm for small animal scanners can be detected

  19. Performance and equipments upgrade of compact nuclear simulator

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jae Chang; Kwon, Kee Choon; Sim, Bong Shick; Kim, Jung Taek; Lee, Dong Young; Kim, Chang Hwoi; Park, Won Man; Song, Soon Ja; Yoo, Soon Duk; Yang, Kwang Nam

    1997-12-01

    The compact nuclear simulator (CNS) is installed in the Korea Atomic Energy Research Institute (KAERI) Nuclear Training Center in 1988. The CNS has been used for training of non-operator personnel such as NSSS design engineers, maintenance personnel, inspectors of regulatory body, etc. and for test facility of fuzzy control algorithm. The CNS was manufactured by KAERI and Studsvik (now Eurosim) joint project. The CNS mathematical modeling modeled a three loop Westinghouse Pressurizer Water Reactor (PWR), 993 MWe, mostly referred to as the Kori Unit 3 and 4 in Korea. But the main computer (Micro VAX II), a interface card between main computer and operator panel, and a graphic interface system are faced with frequent troubles by obsolescence and lack of spare parts. According to the above reasons, the CNS hardware should be replaced by state of the art equipment. It is planned to replace the main computer with HP workstation, a dedicated interface card with a PLC-based interface system, and a graphic interface system with an X-terminal based full graphics system. The software for a instructor console also will be modified text-based to Motif-based user interface. The Motif-based user interface provides more efficient and easy operation in a instructor console also will be modified text-based to Motif-based user interface. The Motif-based user interface provides more efficient and easy operation in a instructor console. (author). 124 refs., 2 tabs., 24 figs

  20. Structural performance of HEPA filters under simulated tornado conditions

    International Nuclear Information System (INIS)

    Horak, H.L.; Gregory, W.S.; Ricketts, C.I.; Smith, P.R.

    1982-02-01

    This report contains the results of structural tests to determine the response of High Efficiency Particulate Air filters to simulated tornado conditions. The data include the structural limits of the filters, their resistance at high flow rates, and the effects of filter design features and tornado parameters. Considering all the filters tested, the mean break pressure or structural limit was found to be 2.35 pse (16.2 kPa). The maximum value was 2.87 psi (19.8 kPa), and the low value found was 1.31 psi (9.0 kPa). The type of failure was usually a medium break of the downstream filter fold. The type of filters that were evaluated were nuclear grade with design flow rates of 1000 cfm (0.472 m 3 /s), standard separators, and folded medium design. The parameters evaluated that are characteristic of the filter included manufacturer, separator type, faceguards, pack tightness, and aerosol loading. Manufacturer and medium properties were found to have a large effect on the structural limits

  1. Improving operational anodising process performance using simulation approach

    International Nuclear Information System (INIS)

    Liong, Choong-Yeun; Ghazali, Syarah Syahidah

    2015-01-01

    The use of aluminium is very widespread, especially in transportation, electrical and electronics, architectural, automotive and engineering applications sectors. Therefore, the anodizing process is an important process for aluminium in order to make the aluminium durable, attractive and weather resistant. This research is focused on the anodizing process operations in manufacturing and supplying of aluminium extrusion. The data required for the development of the model is collected from the observations and interviews conducted in the study. To study the current system, the processes involved in the anodizing process are modeled by using Arena 14.5 simulation software. Those processes consist of five main processes, namely the degreasing process, the etching process, the desmut process, the anodizing process, the sealing process and 16 other processes. The results obtained were analyzed to identify the problems or bottlenecks that occurred and to propose improvement methods that can be implemented on the original model. Based on the comparisons that have been done between the improvement methods, the productivity could be increased by reallocating the workers and reducing loading time

  2. Performance analysis and simulation of vertical gallium nitride nanowire transistors

    Science.gov (United States)

    Witzigmann, Bernd; Yu, Feng; Frank, Kristian; Strempel, Klaas; Fatahilah, Muhammad Fahlesa; Schumacher, Hans Werner; Wasisto, Hutomo Suryo; Römer, Friedhard; Waag, Andreas

    2018-06-01

    Gallium nitride (GaN) nanowire transistors are analyzed using hydrodynamic simulation. Both p-body and n-body devices are compared in terms of threshold voltage, saturation behavior and transconductance. The calculations are calibrated using experimental data. The threshold voltage can be tuned from enhancement to depletion mode with wire doping. Surface states cause a shift of threshold voltage and saturation current. The saturation current depends on the gate design, with a composite gate acting as field plate in the p-body device. He joined Bell Laboratories, Murray Hill, NJ, as a Technical Staff Member. In October 2001, he joined the Optical Access and Transport Division, Agere Systems, Alhambra, CA. In 2004, he was appointed an Assistant Professor at ETH Zurich,. Since 2008, at the University of Kassel, Kassel, Germany, and he has been a Professor the Head of the Computational Electronics and Photonics Group, and co-director of CINSaT since 2010. His research interests include computational optoelectronics, process and device design of semiconductor photonic devices, microwave components, and electromagnetics modeling for nanophotonics. Dr. Witzigmann is a senior member of the SPIE and IEEE.

  3. Improving operational anodising process performance using simulation approach

    Energy Technology Data Exchange (ETDEWEB)

    Liong, Choong-Yeun, E-mail: lg@ukm.edu.my; Ghazali, Syarah Syahidah, E-mail: syarah@gapps.kptm.edu.my [School of Mathematical Sciences, Faculty of Science and Technology, Universiti Kebangsaan Malaysia, 43600 UKM Bangi, Selangor DE (Malaysia)

    2015-10-22

    The use of aluminium is very widespread, especially in transportation, electrical and electronics, architectural, automotive and engineering applications sectors. Therefore, the anodizing process is an important process for aluminium in order to make the aluminium durable, attractive and weather resistant. This research is focused on the anodizing process operations in manufacturing and supplying of aluminium extrusion. The data required for the development of the model is collected from the observations and interviews conducted in the study. To study the current system, the processes involved in the anodizing process are modeled by using Arena 14.5 simulation software. Those processes consist of five main processes, namely the degreasing process, the etching process, the desmut process, the anodizing process, the sealing process and 16 other processes. The results obtained were analyzed to identify the problems or bottlenecks that occurred and to propose improvement methods that can be implemented on the original model. Based on the comparisons that have been done between the improvement methods, the productivity could be increased by reallocating the workers and reducing loading time.

  4. Improving operational anodising process performance using simulation approach

    Science.gov (United States)

    Liong, Choong-Yeun; Ghazali, Syarah Syahidah

    2015-10-01

    The use of aluminium is very widespread, especially in transportation, electrical and electronics, architectural, automotive and engineering applications sectors. Therefore, the anodizing process is an important process for aluminium in order to make the aluminium durable, attractive and weather resistant. This research is focused on the anodizing process operations in manufacturing and supplying of aluminium extrusion. The data required for the development of the model is collected from the observations and interviews conducted in the study. To study the current system, the processes involved in the anodizing process are modeled by using Arena 14.5 simulation software. Those processes consist of five main processes, namely the degreasing process, the etching process, the desmut process, the anodizing process, the sealing process and 16 other processes. The results obtained were analyzed to identify the problems or bottlenecks that occurred and to propose improvement methods that can be implemented on the original model. Based on the comparisons that have been done between the improvement methods, the productivity could be increased by reallocating the workers and reducing loading time.

  5. RANS Simulations of Aerodynamic Performance of NACA 0015 Flapped Airfoil

    Directory of Open Access Journals (Sweden)

    Sohaib Obeid

    2017-01-01

    Full Text Available An analysis of 2D subsonic flow over an NACA 0015 airfoil with a 30% trailing edge flap at a constant Reynolds number of 106 for various incidence angles and a range of flap deflections is presented. The steady-state governing equations of continuity and momentum conservation are solved combined with the realizable k-ε turbulence model using the ANSYS-Fluent code (Version 13.7, ANSYS, Inc., Canonsburg, PA, USA. The primary objective of the study is to provide a comprehensive understanding of flow characteristics around the NACA 0015 airfoil as a function of the angle of attack and flap deflection at Re = 106 using the realizable k-ε turbulence model. The results are validated through comparison of the predictions with the free field experimental measurements. Consistent with the experimental observations, the numerical results show that increased flap deflections increase the maximum lift coefficient, move the zero-lift angle of attack (AoA to a more negative value, decrease the stall AoA, while the slope of the lift curve remains unchanged and the curve just shifts upwards. In addition, the numerical simulations provide limits for lift increment Δ C l and Cl, max values to be 1.1 and 2.2, respectively, obtained at a flap deflection of 50°. This investigation demonstrates that the realizable k-ε turbulence model is capable of predicting flow features over an airfoil with and without flap deflections with reasonable accuracy.

  6. Mild Traumatic Brain Injury and Dynamic Simulated Shooting Performance

    Science.gov (United States)

    2016-02-01

    differences between tasks. All pairwise comparisons were adjusted with a Sidak correction for multiple comparisons. TLX scores 0 5 10 15 20 25 30 35...research at multiple sites. Specific to the question of MTBI-related balance, we recommend that future studies seek, when feasible, to quantify body sway...higher ratings of perceived workload. In addition, the alternate analyses yielded some preliminary evidence of shooting performance decrements

  7. A high performance scientific cloud computing environment for materials simulations

    OpenAIRE

    Jorissen, Kevin; Vila, Fernando D.; Rehr, John J.

    2011-01-01

    We describe the development of a scientific cloud computing (SCC) platform that offers high performance computation capability. The platform consists of a scientific virtual machine prototype containing a UNIX operating system and several materials science codes, together with essential interface tools (an SCC toolset) that offers functionality comparable to local compute clusters. In particular, our SCC toolset provides automatic creation of virtual clusters for parallel computing, including...

  8. [Lack of correlation between performances in a simulator and in reality].

    Science.gov (United States)

    Konge, Lars; Bitsch, Mikael

    2010-12-13

    Simulation-based training provides obvious benefits for patients and doctors in education. Frequently, virtual reality simulators are expensive and evidence for their efficacy is poor, particularly as a result of studies with poor methodology and few test participants. In medical simulated training- and evaluation programmes it is always a question of transfer to the real clinical world. To illustrate this problem a study comparing the test performance of persons on a bowling simulator with their performance in a real bowling alley was conducted. Twenty-five test subjects played two rounds of bowling on a Nintendo Wii and 25 days later on a real bowling alley. Correlations of the scores in the first and second round (test-retest-reliability) and of the scores on the simulator and in reality (criterion validation) were studied and there was tested for any difference between female and male performance. The intraclass correlation coefficient equalled 0.76, i.e. the simulator fairly accurately measured participant performance. In contrast to this there was absolutely no correlation between participants' real bowling abilities and their scores on the simulator (Pearson's r = 0.06). There was no significant difference between female and male abilities. Simulation-based testing and training must be based on evidence. More studies are needed to include an adequate number of subjects. Bowling competence should not be based on Nintendo Wii measurements. Simulated training- and evaluation programmes should be validated before introduction, to ensure consistency with the real world.

  9. Reliability-based performance simulation for optimized pavement maintenance

    International Nuclear Information System (INIS)

    Chou, Jui-Sheng; Le, Thanh-Son

    2011-01-01

    Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: →A novel algorithm using multi-objective particle swarm optimization technique. → Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. → A probabilistic model for regression parameters is employed to assess reliability-based performance. → The proposed approach can help decision makers to optimize roadway maintenance plans.

  10. Reliability-based performance simulation for optimized pavement maintenance

    Energy Technology Data Exchange (ETDEWEB)

    Chou, Jui-Sheng, E-mail: jschou@mail.ntust.edu.tw [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China); Le, Thanh-Son [Department of Construction Engineering, National Taiwan University of Science and Technology (Taiwan Tech), 43 Sec. 4, Keelung Rd., Taipei 106, Taiwan (China)

    2011-10-15

    Roadway pavement maintenance is essential for driver safety and highway infrastructure efficiency. However, regular preventive maintenance and rehabilitation (M and R) activities are extremely costly. Unfortunately, the funds available for the M and R of highway pavement are often given lower priority compared to other national development policies, therefore, available funds must be allocated wisely. Maintenance strategies are typically implemented by optimizing only the cost whilst the reliability of facility performance is neglected. This study proposes a novel algorithm using multi-objective particle swarm optimization (MOPSO) technique to evaluate the cost-reliability tradeoff in a flexible maintenance strategy based on non-dominant solutions. Moreover, a probabilistic model for regression parameters is employed to assess reliability-based performance. A numerical example of a highway pavement project is illustrated to demonstrate the efficacy of the proposed MOPSO algorithms. The analytical results show that the proposed approach can help decision makers to optimize roadway maintenance plans. - Highlights: > A novel algorithm using multi-objective particle swarm optimization technique. > Evaluation of the cost-reliability tradeoff in a flexible maintenance strategy. > A probabilistic model for regression parameters is employed to assess reliability-based performance. > The proposed approach can help decision makers to optimize roadway maintenance plans.

  11. Numerical simulation of a twin screw expander for performance prediction

    Science.gov (United States)

    Papes, Iva; Degroote, Joris; Vierendeels, Jan

    2015-08-01

    With the increasing use of twin screw expanders in waste heat recovery applications, the performance prediction of these machines plays an important role. This paper presents a mathematical model for calculating the performance of a twin screw expander. From the mass and energy conservation laws, differential equations are derived which are then solved together with the appropriate Equation of State in the instantaneous control volumes. Different flow processes that occur inside the screw expander such as filling (accompanied by a substantial pressure loss) and leakage flows through the clearances are accounted for in the model. The mathematical model employs all geometrical parameters such as chamber volume, suction and leakage areas. With R245fa as working fluid, the Aungier Redlich-Kwong Equation of State has been used in order to include real gas effects. To calculate the mass flow rates through the leakage paths formed inside the screw expander, flow coefficients are considered as constant and they are derived from 3D Computational Fluid Dynamic calculations at given working conditions and applied to all other working conditions. The outcome of the mathematical model is the P-V indicator diagram which is compared to CFD results of the same twin screw expander. Since CFD calculations require significant computational time, developed mathematical model can be used for the faster performance prediction.

  12. Parallel Performance Optimizations on Unstructured Mesh-based Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Sarje, Abhinav; Song, Sukhyun; Jacobsen, Douglas; Huck, Kevin; Hollingsworth, Jeffrey; Malony, Allen; Williams, Samuel; Oliker, Leonid

    2015-01-01

    © The Authors. Published by Elsevier B.V. This paper addresses two key parallelization challenges the unstructured mesh-based ocean modeling code, MPAS-Ocean, which uses a mesh based on Voronoi tessellations: (1) load imbalance across processes, and (2) unstructured data access patterns, that inhibit intra- and inter-node performance. Our work analyzes the load imbalance due to naive partitioning of the mesh, and develops methods to generate mesh partitioning with better load balance and reduced communication. Furthermore, we present methods that minimize both inter- and intranode data movement and maximize data reuse. Our techniques include predictive ordering of data elements for higher cache efficiency, as well as communication reduction approaches. We present detailed performance data when running on thousands of cores using the Cray XC30 supercomputer and show that our optimization strategies can exceed the original performance by over 2×. Additionally, many of these solutions can be broadly applied to a wide variety of unstructured grid-based computations.

  13. Review of Methods Related to Assessing Human Performance in Nuclear Power Plant Control Room Simulations

    Energy Technology Data Exchange (ETDEWEB)

    Katya L Le Blanc; Ronald L Boring; David I Gertman

    2001-11-01

    With the increased use of digital systems in Nuclear Power Plant (NPP) control rooms comes a need to thoroughly understand the human performance issues associated with digital systems. A common way to evaluate human performance is to test operators and crews in NPP control room simulators. However, it is often challenging to characterize human performance in meaningful ways when measuring performance in NPP control room simulations. A review of the literature in NPP simulator studies reveals a variety of ways to measure human performance in NPP control room simulations including direct observation, automated computer logging, recordings from physiological equipment, self-report techniques, protocol analysis and structured debriefs, and application of model-based evaluation. These methods and the particular measures used are summarized and evaluated.

  14. Modeling and Simulation of Ceramic Arrays to Improve Ballistic Performance

    Science.gov (United States)

    2014-04-30

    Impact with no Adhesive DOP (mm) 10.3 □ □ An adhesive layer of Epoxy Resin was added in between the SiC tile and the Al backing The tile...Tile Gap 0.508 mm with No Adhesive DOP (mm) 17.2 □ An adhesive layer of Epoxy Resin was added in between the SiC tile and the Al backing The...Baseline performance seam assessment (2 ft x 2 ft panels) □ Sintered 4’sq. SiC (Superior Graphite) on Kevlar /Phenolic with 2-ply cover Cover (a

  15. Web proxy cache replacement strategies simulation, implementation, and performance evaluation

    CERN Document Server

    ElAarag, Hala; Cobb, Jake

    2013-01-01

    This work presents a study of cache replacement strategies designed for static web content. Proxy servers can improve performance by caching static web content such as cascading style sheets, java script source files, and large files such as images. This topic is particularly important in wireless ad hoc networks, in which mobile devices act as proxy servers for a group of other mobile devices. Opening chapters present an introduction to web requests and the characteristics of web objects, web proxy servers and Squid, and artificial neural networks. This is followed by a comprehensive review o

  16. The effect of self-directed virtual reality simulation on dissection training performance in mastoidectomy

    DEFF Research Database (Denmark)

    Andersen, Steven Arild Wuyts; Foghsgaard, Søren; Konge, Lars

    2016-01-01

    OBJECTIVES/HYPOTHESIS: To establish the effect of self-directed virtual reality (VR) simulation training on cadaveric dissection training performance in mastoidectomy and the transferability of skills acquired in VR simulation training to the cadaveric dissection training setting. STUDY DESIGN......: Prospective study. METHODS: Two cohorts of 20 novice otorhinolaryngology residents received either self-directed VR simulation training before cadaveric dissection training or vice versa. Cadaveric and VR simulation performances were assessed using final-product analysis with three blinded expert raters....... RESULTS: The group receiving VR simulation training before cadaveric dissection had a mean final-product score of 14.9 (95 % confidence interval [CI] [12.9-16.9]) compared with 9.8 (95% CI [8.4-11.1]) in the group not receiving VR simulation training before cadaveric dissection. This 52% increase...

  17. Comments on ''Use of conditional simulation in nuclear waste site performance assessment'' by Carol Gotway

    International Nuclear Information System (INIS)

    Downing, D.J.

    1993-01-01

    This paper discusses Carol Gotway's paper, ''The Use of Conditional Simulation in Nuclear Waste Site Performance Assessment.'' The paper centers on the use of conditional simulation and the use of geostatistical methods to simulate an entire field of values for subsequent use in a complex computer model. The issues of sampling designs for geostatistics, semivariogram estimation and anisotropy, turning bands method for random field generation, and estimation of the comulative distribution function are brought out

  18. Performance simulations for Co-gasification of coal and methane

    Energy Technology Data Exchange (ETDEWEB)

    Niksa, Stephen [Niksa Energy Associates LLC, Belmont, CA (United States); Lim, J.P.; Del Rio Diaz Jara, D.; Eckstrom, D.; Steele, D.; Malhotra, R.; Wilson, R.B. [SRI International, Menlo Park, CA (United States). Chemistry and Chemical Engineering Dept.

    2013-07-01

    In the process under development, coal suspended in mixtures of CH{sub 4}, H{sub 2}, and steam is rapidly heated to temperatures above 1,400 C under 5-7 MPa for at least 1 s. The coal first decomposes into volatiles and char while CH{sub 4} is converted into CO/H{sub 2} mixtures. Then the char is converted into CO/H{sub 2} mixtures via steam gasification on longer time scales, and into CH{sub 4} via hydrogasification. Throughout all stages, homogeneous chemistry reforms all intermediate fuel components into the syngas feedstock for methanol synthesis. Fully validated reaction mechanisms for each chemical process were used to quantitatively interpret a co-gasification test series in SRI's lab-scale gasification facility. Homogeneous reforming chemistry generates equilibrium gas compositions at 1,500 C in the available transit time of 1.4 s, but not at any of the lower temperatures. Methane conversion in the gas phase increases for progressively hotter temperatures, in accord with the data. But the strong predicted dependence on steam concentration was not evident in the measured CH{sub 4} conversions, even when steam concentration was the subject test variable. Char hydrogasification adds CH{sub 4} to the product gas stream, but this process probably converts no more than 15-20% of the char in the lab-scale tests and the bulk of the char is converted by steam gasification. The correlation coefficient between predicted and measured char conversions exceeded 0.8 and the std. dev. was 3.4%, which is comparable to the measurement uncertainties. The evaluation of the predicted CH{sub 4} conversions gave a std. dev. greater than 20%. Simulations of commercial conditions with realistic suspension loadings and no diluents in the feed gave slightly lower conversions of both CH{sub 4} and coal, because hydrogasification accounts for more of the char conversion, and occurs at rates slower than for steam gasification.

  19. Mastoidectomy performance assessment of virtual simulation training using final-product analysis

    DEFF Research Database (Denmark)

    Andersen, Steven A W; Cayé-Thomasen, Per; Sørensen, Mads S

    2015-01-01

    a modified Welling scale. The simulator gathered basic metrics on time, steps, and volumes in relation to the on-screen tutorial and collisions with vital structures. RESULTS: Substantial inter-rater reliability (kappa = 0.77) for virtual simulation and moderate inter-rater reliability (kappa = 0.......59) for dissection final-product assessment was found. The simulation and dissection performance scores had significant correlation (P = .014). None of the basic simulator metrics correlated significantly with the final-product score except for number of steps completed in the simulator. CONCLUSIONS: A modified...... version of a validated final-product performance assessment tool can be used to assess mastoidectomy on virtual temporal bones. Performance assessment of virtual mastoidectomy could potentially save the use of cadaveric temporal bones for more advanced training when a basic level of competency...

  20. Simulation of the ASDEX divertor performance after hardening

    International Nuclear Information System (INIS)

    Schneider, W.; Lackner, K.; Neuhauser, J.; Wunderlich, R.

    1985-05-01

    Two combined computer models - a fluid description of the plasma scrape-off layer (SOLID) and a Monte-Carlo code for the neutral gas dynamics (DEGAS) - are used to assess changes in the divertor performance expected from the modifications in geometry needed for hardening the ASDEX divertor chamber for long-pulse, high-power heating. Stand-alone DEGAS calculations with assumed fixed scrape-off plasma parameters predict a doubling of the neutral escape probability, which, however, still remains so low, that achievement of the high divertor recycling regime can be expected over roughly the same operational regime as before modifications. This conclusion is also supported by fully self-consistent calculations with the combined model. Due to the reduced divertor, a significant reduction is predicted in the divertor time constant, which is expected to affect transient phenomena. (orig.)

  1. Simulation-Based Performance Assessment: An Innovative Approach to Exploring Understanding of Physical Science Concepts

    Science.gov (United States)

    Gale, Jessica; Wind, Stefanie; Koval, Jayma; Dagosta, Joseph; Ryan, Mike; Usselman, Marion

    2016-01-01

    This paper illustrates the use of simulation-based performance assessment (PA) methodology in a recent study of eighth-grade students' understanding of physical science concepts. A set of four simulation-based PA tasks were iteratively developed to assess student understanding of an array of physical science concepts, including net force,…

  2. Proceedings of eSim 2006 : IBPSA-Canada's 4. biennial building performance simulation conference

    International Nuclear Information System (INIS)

    Kesik, T.

    2006-01-01

    This conference was attended by professionals, academics and students interested in promoting the science of building performance simulation in order to optimize design, construction, operation and maintenance of new and existing buildings around the world. This biennial conference and exhibition covered all topics related to computerized simulation of a building's energy performance and energy efficiency. Computerized simulation is widely used to predict the environmental performance of buildings during all stages of a building's life cycle, from the design, commissioning, construction, occupancy and management stages. Newly developed simulation methods for optimal comfort in new and existing buildings were evaluated. The themes of the conference were: recent developments for modelling the physical processes relevant to buildings; algorithms for modelling conventional and innovative HVAC systems; methods for modelling whole-building performance; building simulation software development; the use of building simulation tools in code compliance; moving simulation into practice; validation of building simulation software; architectural design; and optimization approaches in building design. The conference also covered the modeling of energy supply systems with reference to renewable energy sources such as ground source heat pumps or hybrid systems incorporating solar energy. The conference featured 32 presentations, of which 28 have been catalogued separately for inclusion in this database. refs., tabs., figs

  3. Performance simulation of the X-ray spectrometer in Chang'E-1 satellite payload

    International Nuclear Information System (INIS)

    Cao Xuelei; Wang Huanyu; Zhang Chengmo; Chen Yong; Yang Jiawei; Wang JInzhou; Liang Xiaohua; Gao Min; Zhang Jiayu; Ma Guofeng

    2007-01-01

    We discuss the performance simulation of the X-ray Spectrometer in Chang'E-1 satellite based on Geant4 system. It is divided in three parts, the efficiency simulation, the energy spectrum response and direction response. It provides the guidance on making the spectrometer. (authors)

  4. Simulated Environments with Animated Agents: Effects on Visual Attention, Emotion, Performance, and Perception

    Science.gov (United States)

    Romero-Hall, E.; Watson, G. S.; Adcock, A.; Bliss, J.; Adams Tufts, K.

    2016-01-01

    This research assessed how emotive animated agents in a simulation-based training affect the performance outcomes and perceptions of the individuals interacting in real time with the training application. A total of 56 participants consented to complete the study. The material for this investigation included a nursing simulation in which…

  5. High Performance Electrical Modeling and Simulation Verification Test Suite - Tier I; TOPICAL

    International Nuclear Information System (INIS)

    SCHELLS, REGINA L.; BOGDAN, CAROLYN W.; WIX, STEVEN D.

    2001-01-01

    This document describes the High Performance Electrical Modeling and Simulation (HPEMS) Global Verification Test Suite (VERTS). The VERTS is a regression test suite used for verification of the electrical circuit simulation codes currently being developed by the HPEMS code development team. This document contains descriptions of the Tier I test cases

  6. Selection criteria for building performance simulation tools : contrasting architects' and engineers' needs

    NARCIS (Netherlands)

    Attia, S.G.; Hensen, J.L.M.; Beltran, L.; De Herde, A.

    2012-01-01

    This article summarises a study undertaken to reveal potential challenges and opportunities for using building performance simulation (BPS) tools. The article reviews current trends in building simulation and outlines major criteria for BPS tool selection and evaluation based on analysing users'

  7. Effects of MDMA (ecstasy), and multiple drugs use on (simulated) driving performance and traffic safety

    NARCIS (Netherlands)

    Brookhuis, KA; de Waard, D; Samyn, N

    Rationale. The effects of MDMA on driving behaviour are not clear, since the direct effects of MDMA on cognitive performance are reported as not generally negative. Objectives. To assess in an advanced driving simulator acute effects on simulated driving behaviour and heart rate of MDMA, and effects

  8. Early decision support for net zero energy buildings design using building performance simulation

    NARCIS (Netherlands)

    Attia, S.G.; Gratia, E.; De Herde, A.; Hensen, J.L.M.

    2013-01-01

    This paper aims to investigate the use of building performance simulation tools as a method of informing the design decision of NZEBs. The aim of this study is to evaluate the effect of a simulation-based decision aid, ZEBO, on informed decision-making using sensitivity analysis. The objective is to

  9. The current role of simulators for performance evaluations and licensing (case of Mexico)

    International Nuclear Information System (INIS)

    Maldonado A, H.

    1997-01-01

    The main purpose of this paper is to share the experience acquired by the National Commission of Nuclear Safety and Safeguards (CNSNS) during the administration of both certification and licensing operational exams applied to Senior Reactor Operators (SRO) and Reactor OPerators (RO) by using a full-scope simulator. The licensing operational exams are administered to examinate candidates for a SRO or RO license while the certification operational exams are administered to all personnel that possess a SRO or RO license in order to renew their licenses within a six years period. A general description with the most important simulator antecedents from the initial authorization for its usage to provide the ''Initial Simulator Training Course'' until currently in which it has been started the installation and testing performance of a new computer equipment that will improve and increase the simulation capacity of the Laguna Verde Nuclear Power Plant (LVNPP) simulator. In other hand, it is showed the process that the CNSNS will apply during the next verification of the simulator certification which should be performed due to the old computer equipment is being replaced with a more modern computer equipment so that the simulation capability will be improved. The verification process was discussed with the utility personnel and as result of this an agreement has been established to carry into effect this hard task. Finally, the conclusions and recommendations from regulators point of view are presented regarding to the importance of perform a well both evaluation and verification of simulators performance. (author)

  10. Integrated Simulation for HVAC Performance Prediction: State-of-the-Art Illustration

    NARCIS (Netherlands)

    Hensen, J.L.M.; Clarke, J.A.

    2000-01-01

    This paper aims to outline the current state-of-the-art in integrated building simulation for performance prediction of heating, ventilating and air-conditioning (HVAC) systems. The ESP-r system is used as an example where integrated simulation is a core philosophy behind the development. The

  11. Bench performance of ventilators during simulated paediatric ventilation.

    Science.gov (United States)

    Park, M A J; Freebairn, R C; Gomersall, C D

    2013-05-01

    This study compares the accuracy and capabilities of various ventilators using a paediatric acute respiratory distress syndrome lung model. Various compliance settings and respiratory rate settings were used. The study was done in three parts: tidal volume and FiO2 accuracy; pressure control accuracy and positive end-expiratory pressure (PEEP) accuracy. The parameters set on the ventilator were compared with either or both of the measured parameters by the test lung and the ventilator. The results revealed that none of the ventilators could consistently deliver tidal volumes within 1 ml/kg of the set tidal volume, and the discrepancy between the delivered volume and the volume measured by the ventilator varied greatly. The target tidal volume was 8 ml/kg, but delivered tidal volumes ranged from 3.6-11.4 ml/kg and the volumes measured by the ventilator ranged from 4.1-20.6 ml/kg. All the ventilators maintained pressure within 20% of the set pressure, except one ventilator which delivered pressures of up to 27% higher than the set pressure. Two ventilators maintained PEEP within 10% of the prescribed PEEP. The majority of the readings were also within 10%. However, three ventilators delivered, at times, PEEPs over 20% higher. In conclusion, as lung compliance decreases, especially in paediatric patients, some ventilators perform better than others. This study highlights situations where ventilators may not be able to deliver, nor adequately measure, set tidal volumes, pressure, PEEP or FiO2.

  12. In Patients with Cirrhosis, Driving Simulator Performance is Associated With Real-life Driving

    DEFF Research Database (Denmark)

    Lauridsen, Mette Enok Munk; Thacker, Leroy R; White, Melanie B

    2016-01-01

    BACKGROUND & AIMS: Minimal hepatic encephalopathy (MHE) has been linked to higher real-life rates of automobile crashes and poor performance in driving simulation studies, but the link between driving simulator performance and real-life automobile crashes has not been clearly established. Further......, not all patients with MHE are unsafe drivers, but it is unclear how to distinguish them from unsafe drivers. We investigated the link between performance on driving simulators and real-life automobile accidents and traffic violations. We also aimed to identify features of unsafe drivers with cirrhosis...... and evaluated changes in simulated driving skills and MHE status after 1 year. METHODS: We performed a study of outpatients with cirrhosis (n=205; median 55 years old; median model for end-stage liver disease score, 9.5; none with overt hepatic encephalopathy or alcohol or illicit drug use within previous 6...

  13. submitter Simulation-Based Performance Analysis of the ALICE Mass Storage System

    CERN Document Server

    Vickovic, L; Celar, S

    2016-01-01

    CERN – the European Organization for Nuclear Research today, in the era of big data, is one of the biggest data generators in the world. Especially interesting is transient data storage system in the ALICE experiment. With the goal to optimize its performance this paper discusses a dynamic, discrete event simulation model of disk based Storage Area Network (SAN) and its usage for the performance analyses. Storage system model is based on modular, bottom up approach and the differences between measured and simulated values vary between 1.5 % and 4 % depending on the simulated component. Once finished, simulation model was used for detailed performance analyses. Among other findings it showed that system performances can be seriously affected if the array stripe size is larger than the size of cache on individual disks in the array, which so far has been completely ignored in the literature.

  14. Rate of initial recovery and subsequent radar monitoring performance following a simulated emergency involving startle.

    Science.gov (United States)

    1983-09-01

    The present study employed auditory startle to simulate the principal components (unexpectedness, fear, and physiological arousal) that are common to many types of sudden emergencies and compared performance recovery following startle with recovery f...

  15. Impact of Hypobarism During Simulated Transport on Critical Care Air Transport Team Performance

    Science.gov (United States)

    2017-04-26

    AFRL-SA-WP-SR-2017-0008 Impact of Hypobarism During Simulated Transport on Critical Care Air Transport Team Performance Dina...July 2014 – November 2016 4. TITLE AND SUBTITLE Impact of Hypobarism During Simulated Transport on Critical Care Air Transport Team Performance 5a...During Critical Care Air Transport Team Advanced Course validation, three-member teams consisting of a physician, nurse, and respiratory therapist

  16. Analysis for Parallel Execution without Performing Hardware/Software Co-simulation

    OpenAIRE

    Muhammad Rashid

    2014-01-01

    Hardware/software co-simulation improves the performance of embedded applications by executing the applications on a virtual platform before the actual hardware is available in silicon. However, the virtual platform of the target architecture is often not available during early stages of the embedded design flow. Consequently, analysis for parallel execution without performing hardware/software co-simulation is required. This article presents an analysis methodology for parallel execution of ...

  17. Modeling of HVAC operational faults in building performance simulation

    International Nuclear Information System (INIS)

    Zhang, Rongpeng; Hong, Tianzhen

    2017-01-01

    Highlights: •Discuss significance of capturing operational faults in existing buildings. •Develop a novel feature in EnergyPlus to model operational faults of HVAC systems. •Compare three approaches to faults modeling using EnergyPlus. •A case study demonstrates the use of the fault-modeling feature. •Future developments of new faults are discussed. -- Abstract: Operational faults are common in the heating, ventilating, and air conditioning (HVAC) systems of existing buildings, leading to a decrease in energy efficiency and occupant comfort. Various fault detection and diagnostic methods have been developed to identify and analyze HVAC operational faults at the component or subsystem level. However, current methods lack a holistic approach to predicting the overall impacts of faults at the building level—an approach that adequately addresses the coupling between various operational components, the synchronized effect between simultaneous faults, and the dynamic nature of fault severity. This study introduces the novel development of a fault-modeling feature in EnergyPlus which fills in the knowledge gap left by previous studies. This paper presents the design and implementation of the new feature in EnergyPlus and discusses in detail the fault-modeling challenges faced. The new fault-modeling feature enables EnergyPlus to quantify the impacts of faults on building energy use and occupant comfort, thus supporting the decision making of timely fault corrections. Including actual building operational faults in energy models also improves the accuracy of the baseline model, which is critical in the measurement and verification of retrofit or commissioning projects. As an example, EnergyPlus version 8.6 was used to investigate the impacts of a number of typical operational faults in an office building across several U.S. climate zones. The results demonstrate that the faults have significant impacts on building energy performance as well as on occupant

  18. A fast and compact Fuel Rod Performance Simulator code for predictive, interpretive and educational purpose

    International Nuclear Information System (INIS)

    Lorenzen, J.

    1990-01-01

    A new Fuel rod Performance Simulator code FRPS has been developed, tested and benchmarked and is now available in different versions. The user may choose between the batch version INTERPIN producing results in form of listings or beforehand defined plots, or the interactive simulator code SIMSIM which is stepping through a power history under the control of user. Both versions are presently running on minicomputers and PC:s using EGA-Graphics. A third version is the implementation in a Studsvik Compact Simulator with FRPS being one of its various modules receiving the dynamic inputs from the simulator

  19. Stochastic Processes and Queueing Theory used in Cloud Computer Performance Simulations

    Directory of Open Access Journals (Sweden)

    Florin-Catalin ENACHE

    2015-10-01

    Full Text Available The growing character of the cloud business has manifested exponentially in the last 5 years. The capacity managers need to concentrate on a practical way to simulate the random demands a cloud infrastructure could face, even if there are not too many mathematical tools to simulate such demands.This paper presents an introduction into the most important stochastic processes and queueing theory concepts used for modeling computer performance. Moreover, it shows the cases where such concepts are applicable and when not, using clear programming examples on how to simulate a queue, and how to use and validate a simulation, when there are no mathematical concepts to back it up.

  20. Performance evaluation by simulation and analysis with applications to computer networks

    CERN Document Server

    Chen, Ken

    2015-01-01

    This book is devoted to the most used methodologies for performance evaluation: simulation using specialized software and mathematical modeling. An important part is dedicated to the simulation, particularly in its theoretical framework and the precautions to be taken in the implementation of the experimental procedure.  These principles are illustrated by concrete examples achieved through operational simulation languages ​​(OMNeT ++, OPNET). Presented under the complementary approach, the mathematical method is essential for the simulation. Both methodologies based largely on the theory of

  1. Pharmacy practice simulations: performance of senior pharmacy students at a University in southern Brazil

    Directory of Open Access Journals (Sweden)

    Galato D

    2011-09-01

    Full Text Available Objective: A simulation process known as objective structured clinical examination (OSCE was applied to assess pharmacy practice performed by senior pharmacy students.Methods: A cross-sectional study was conducted based on documentary analysis of performance evaluation records of pharmacy practice simulations that occurred between 2005 and 2009. These simulations were related to the process of self-medication and dispensing, and were performed with the use of patients simulated. The simulations were filmed to facilitate the evaluation process. It presents the OSCE educational experience performed by pharmacy trainees of the University of Southern Santa Catarina and experienced by two evaluators. The student general performance was analyzed, and the criteria for pharmacy practice assessment often identified trainees in difficulty.Results: The results of 291 simulations showed that students have an average yield performance of 70.0%. Several difficulties were encountered, such as the lack of information about the selected/prescribed treatment regimen (65.1%; inadequate communication style (21.9%; lack of identification of patients’ needs (7.7% and inappropriate drug selection for self-medication (5.3%.Conclusions: These data show that there is a need for reorientation of clinical pharmacy students because they need to improve their communication skills, and have a deeper knowledge of medicines and health problems in order to properly orient their patients.

  2. Evaluating the Effect of Virtual Reality Temporal Bone Simulation on Mastoidectomy Performance: A Meta-analysis.

    Science.gov (United States)

    Lui, Justin T; Hoy, Monica Y

    2017-06-01

    Background The increasing prevalence of virtual reality simulation in temporal bone surgery warrants an investigation to assess training effectiveness. Objectives To determine if temporal bone simulator use improves mastoidectomy performance. Data Sources Ovid Medline, Embase, and PubMed databases were systematically searched per the PRISMA guidelines. Review Methods Inclusion criteria were peer-reviewed publications that utilized quantitative data of mastoidectomy performance following the use of a temporal bone simulator. The search was restricted to human studies published in English. Studies were excluded if they were in non-peer-reviewed format, were descriptive in nature, or failed to provide surgical performance outcomes. Meta-analysis calculations were then performed. Results A meta-analysis based on the random-effects model revealed an improvement in overall mastoidectomy performance following training on the temporal bone simulator. A standardized mean difference of 0.87 (95% CI, 0.38-1.35) was generated in the setting of a heterogeneous study population ( I 2 = 64.3%, P virtual reality simulation temporal bone surgery studies, meta-analysis calculations demonstrate an improvement in trainee mastoidectomy performance with virtual simulation training.

  3. Automating the simulator testing and data collection process

    Energy Technology Data Exchange (ETDEWEB)

    Magi, T.; Dimitri-Hakim, R. [L-3 Communications MAPPS Inc., Montreal, Quebec (Canada)

    2012-07-01

    Scenario-based training is a key process in the use of Full Scope Simulators (FSS) for operator training. Scenario-based training can be defined as any set of simulated plant operations performed with a specific training objective in mind. In order to meet this training objective, the ANSI/ANS-3.5-2009 standard requires that certain simulator training scenarios be tested to ensure that they reproduce the expected plant responses, that all plant procedures can be followed, and that scenario-based training objectives can be met. While malfunction testing provided a narrow view of the simulator performance revolving around the malfunction itself, scenario testing provides a broader, overall view. The concept of instructor validation of simulator scenarios to be used for training and evaluation, and oversight of simulator performance during the validation process, work hand-in-hand. This is where Scenario-Based Testing comes into play. With the description of Scenario-Based Testing (SBT) within Nuclear Energy Institute NEI 09-09 white paper and within the ANSI/ANS-3.5-2009 standard, the industry now has a way forward that reduces the regulatory uncertainty. Together, scenario-based testing and scenario-based training combine to produce better simulators which in turn can be used to more effectively and efficiently train new and existing power plant operators. However, they also impose a significant data gathering and analysis burden on FSS users. L-3 MAPPS Orchid Instructor Station (Orchid IS) facilitates this data gathering and analysis by providing features that automate this process with a simple, centralized, easy to use interface. (author)

  4. Simulation and rubrics: technology and grading student performance in nurse anesthesia education.

    Science.gov (United States)

    Overstreet, Maria; McCarver, Lewis; Shields, John; Patterson, Jordan

    2015-06-01

    The use of simulation technology has introduced a challenge for simulation nurse educators: evaluation of student performance. The subjectivity of student performance evaluation has been in need of improvement. It is imperative to provide clear and consistent information to the learner of expectations for their performance. Educators use objectives to define for the learner what the primary focus will be in the learning activities. Creation of rubrics to replace checklists to evaluate learner performance is a team task. Improved rubrics assist instructors in providing valuable, immediate, and postactivity feedback and consistency among instructors, and improved inter-rater reliability. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Analysis of human performance observed under simulated emergencies of nuclear power plants

    International Nuclear Information System (INIS)

    Park, Jin Kyun; Jung, Won Dea; Kim, Jae Whan; Ha, Jae Joo

    2005-01-01

    Previous studies have continuously and commonly revealed that human performance is decisive factor affecting the safety of complicated process systems. Subsequently, extensive effort has been spent to suggest serviceable countermeasures for human performance related problems under emergencies. However, several obstacles including very limited number of available data have hindered researchers from elucidating effective ways to cope with human performance related problems. In this study, human performance data under simulated emergencies have been extracted using a full scope simulator located in the reference NPP. The main purpose of this study is to provide plant-specific and domain-specific human performance data that can be used to premeditate human performance related problems under emergencies. To accomplish this goal, over 100 records that were collected from retraining sessions for licensed MCR operators have been analyzed by the time-line and protocol analysis technique. As a result, many kinds of useful information that can play a remarkable role in scrutinizing human performance related problems have been secured. Although it is still careful to make some predictions about human performance under a real situation on the basis of that under a simulated situation. However, it is also true that the simulator is a basic tool in observing human behaviors under emergencies. Thus, it is strongly believed that human performance data obtained from this study will be a concrete foundation in scrutinizing the change of human performance under emergencies

  6. A virtual reality dental simulator predicts performance in an operative dentistry manikin course.

    Science.gov (United States)

    Imber, S; Shapira, G; Gordon, M; Judes, H; Metzger, Z

    2003-11-01

    This study was designed to test the ability of a virtual reality dental simulator to predict the performance of students in a traditional operative dentistry manikin course. Twenty-six dental students were pre-tested on the simulator, prior to the course. They were briefly instructed and asked to prepare 12 class I cavities which were automatically graded by the simulator. The instructors in the manikin course that followed were unaware of the students' performances in the simulator pre-test. The scores achieved by each student in the last six simulator cavities were compared to their final comprehensive grades in the manikin course. Class standing of the students in the simulator pre-test positively correlated with their achievements in the manikin course with a correlation coefficient of 0.49 (P = 0.012). Eighty-nine percent of the students in the lower third of the class in the pre-test remained in the low performing half of the class in the manikin course. These results indicate that testing students in a dental simulator, prior to a manikin course, may be an efficient way to allow early identification of those who are likely to perform poorly. This in turn could enable early allocation of personal tutors to these students in order to improve their chances of success.

  7. Multi-Bunch Simulations of the ILC for Luminosity Performance Studies

    CERN Document Server

    White, Glen; Walker, Nicholas J

    2005-01-01

    To study the luminosity performance of the International Linear Collider (ILC) with different design parameters, a simulation was constructed that tracks a multi-bunch representation of the beam from the Damping Ring extraction through to the Interaction Point. The simulation code PLACET is used to simulate the LINAC, MatMerlin is used to track through the Beam Delivery System and GUINEA-PIG for the beam-beam interaction. Included in the simulation are ground motion and wakefield effects, intra-train fast feedback and luminosity-based feedback systems. To efficiently study multiple parameters/multiple seeds, the simulation is deployed on the Queen Mary High-Throughput computing cluster at Queen Mary, University of London, where 100 simultaneous simulation seeds can be run.

  8. High correlation between performance on a virtual-reality simulator and real-life cataract surgery

    DEFF Research Database (Denmark)

    Thomsen, Ann Sofia Skou; Smith, Phillip; Subhi, Yousif

    2017-01-01

    -tracking software of cataract surgical videos with a Pearson correlation coefficient of -0.70 (p = 0.017). CONCLUSION: Performance on the EyeSi simulator is significantly and highly correlated to real-life surgical performance. However, it is recommended that performance assessments are made using multiple data......PURPOSE: To investigate the correlation in performance of cataract surgery between a virtual-reality simulator and real-life surgery using two objective assessment tools with evidence of validity. METHODS: Cataract surgeons with varying levels of experience were included in the study. All...... antitremor training, forceps training, bimanual training, capsulorhexis and phaco divide and conquer. RESULTS: Eleven surgeons were enrolled. After a designated warm-up period, the proficiency-based test on the EyeSi simulator was strongly correlated to real-life performance measured by motion...

  9. A SOFTWARE TOOL TO COMPARE MEASURED AND SIMULATED BUILDING ENERGY PERFORMANCE DATA

    Energy Technology Data Exchange (ETDEWEB)

    Maile, Tobias; Bazjanac, Vladimir; O' Donnell, James; Garr, Matthew

    2011-11-01

    Building energy performance is often inadequate when compared to design goals. To link design goals to actual operation one can compare measured with simulated energy performance data. Our previously developed comparison approach is the Energy Performance Comparison Methodology (EPCM), which enables the identification of performance problems based on a comparison of measured and simulated performance data. In context of this method, we developed a software tool that provides graphing and data processing capabilities of the two performance data sets. The software tool called SEE IT (Stanford Energy Efficiency Information Tool) eliminates the need for manual generation of data plots and data reformatting. SEE IT makes the generation of time series, scatter and carpet plots independent of the source of data (measured or simulated) and provides a valuable tool for comparing measurements with simulation results. SEE IT also allows assigning data points on a predefined building object hierarchy and supports different versions of simulated performance data. This paper briefly introduces the EPCM, describes the SEE IT tool and illustrates its use in the context of a building case study.

  10. Performances on simulator and da Vinci robot on subjects with and without surgical background.

    Science.gov (United States)

    Moglia, Andrea; Ferrari, Vincenzo; Melfi, Franca; Ferrari, Mauro; Mosca, Franco; Cuschieri, Alfred; Morelli, Luca

    2017-08-17

    To assess whether previous training in surgery influences performance on da Vinci Skills Simulator and da Vinci robot. In this prospective study, thirty-seven participants (11 medical students, 17 residents, and 9 attending surgeons) without previous experience in laparoscopy and robotic surgery performed 26 exercises at da Vinci Skills Simulator. Thirty-five then executed a suture using a da Vinci robot. The overall scores on the exercises at the da Vinci Skills Simulator show a similar performance among the groups with no statistically significant pair-wise differences (p poor for the untrained groups (5 (3.5, 9)), without statistically significant difference (p < .05). This study showed, for subjects new to laparoscopy and robotic surgery, insignificant differences in the scores at the da Vinci Skills Simulator and at the da Vinci robot on inanimate models.

  11. Dual Arm Work Package performance estimates and telerobot task network simulation

    International Nuclear Information System (INIS)

    Draper, J.V.

    1997-01-01

    This paper describes the methodology and results of a network simulation study of the Dual Arm Work Package (DAWP), to be employed for dismantling the Argonne National Laboratory CP-5 reactor. The development of the simulation model was based upon the results of a task analysis for the same system. This study was performed by the Oak Ridge National Laboratory (ORNL), in the Robotics and Process Systems Division. Funding was provided the US Department of Energy's Office of Technology Development, Robotics Technology Development Program (RTDP). The RTDP is developing methods of computer simulation to estimate telerobotic system performance. Data were collected to provide point estimates to be used in a task network simulation model. Three skilled operators performed six repetitions of a pipe cutting task representative of typical teleoperation cutting operations

  12. Optical ensemble analysis of intraocular lens performance through a simulated clinical trial with ZEMAX.

    Science.gov (United States)

    Zhao, Huawei

    2009-01-01

    A ZEMAX model was constructed to simulate a clinical trial of intraocular lenses (IOLs) based on a clinically oriented Monte Carlo ensemble analysis using postoperative ocular parameters. The purpose of this model is to test the feasibility of streamlining and optimizing both the design process and the clinical testing of IOLs. This optical ensemble analysis (OEA) is also validated. Simulated pseudophakic eyes were generated by using the tolerancing and programming features of ZEMAX optical design software. OEA methodology was verified by demonstrating that the results of clinical performance simulations were consistent with previously published clinical performance data using the same types of IOLs. From these results we conclude that the OEA method can objectively simulate the potential clinical trial performance of IOLs.

  13. Simulating the Sky as Seen by the Square Kilometer Array using the MIT Array Performance Simulator (MAPS)

    Science.gov (United States)

    Matthews, Lynn D.; Cappallo, R. J.; Doeleman, S. S.; Fish, V. L.; Lonsdale, C. J.; Oberoi, D.; Wayth, R. B.

    2009-05-01

    The Square Kilometer Array (SKA) is a proposed next-generation radio telescope that will operate at frequencies of 0.1-30 GHz and be 50-100 times more sensitive than existing radio arrays. Meeting the performance goals of this instrument will require innovative new hardware and software developments, a variety of which are now under consideration. Key to evaluating the performance characteristics of proposed SKA designs and testing the feasibility of new data calibration and processing algorithms is the ability to carry out realistic simulations of radio wavelength arrays under a variety of observing conditions. The MIT Array Performance Simulator (MAPS) (http://www.haystack.mit.edu/ast/arrays/maps/index.html) is an observations simulation package designed to achieve this goal. MAPS accepts an input source list or sky model and generates a model visibility set for a user-defined "virtual observatory'', incorporating such factors as array geometry, primary beam shape, field-of-view, and time and frequency resolution. Optionally, effects such as thermal noise, out-of-beam sources, variable station beams, and time/location-dependent ionospheric effects can be included. We will showcase current capabilities of MAPS for SKA applications by presenting results from an analysis of the effects of realistic sky backgrounds on the achievable image fidelity and dynamic range of SKA-like arrays comprising large numbers of small-diameter antennas.

  14. A database for human performance under simulated emergencies of nuclear power plants

    International Nuclear Information System (INIS)

    Park, Jin Kyun; Jung, Won Dea

    2005-01-01

    Reliable human performance is a prerequisite in securing the safety of complicated process systems such as nuclear power plants. However, the amount of available knowledge that can explain why operators deviate from an expected performance level is so small because of the infrequency of real accidents. Therefore, in this study, a database that contains a set of useful information extracted from simulated emergencies was developed in order to provide important clues for understanding the change of operators' performance under stressful conditions (i.e., real accidents). The database was developed under Microsoft Windows TM environment using Microsoft Access 97 TM and Microsoft Visual Basic 6.0 TM . In the database, operators' performance data obtained from the analysis of over 100 audio-visual records for simulated emergencies were stored using twenty kinds of distinctive data fields. A total of ten kinds of operators' performance data are available from the developed database. Although it is still difficult to predict operators' performance under stressful conditions based on the results of simulated emergencies, simulation studies remain the most feasible way to scrutinize performance. Accordingly, it is expected that the performance data of this study will provide a concrete foundation for understanding the change of operators' performance in emergency situations

  15. Intraindividual Variability in Basic Reaction Time Predicts Middle-Aged and Older Pilots’ Flight Simulator Performance

    Science.gov (United States)

    2013-01-01

    Objectives. Intraindividual variability (IIV) is negatively associated with cognitive test performance and is positively associated with age and some neurological disorders. We aimed to extend these findings to a real-world task, flight simulator performance. We hypothesized that IIV predicts poorer initial flight performance and increased rate of decline in performance among middle-aged and older pilots. Method. Two-hundred and thirty-six pilots (40–69 years) completed annual assessments comprising a cognitive battery and two 75-min simulated flights in a flight simulator. Basic and complex IIV composite variables were created from measures of basic reaction time and shifting and divided attention tasks. Flight simulator performance was characterized by an overall summary score and scores on communication, emergencies, approach, and traffic avoidance components. Results. Although basic IIV did not predict rate of decline in flight performance, it had a negative association with initial performance for most flight measures. After taking into account processing speed, basic IIV explained an additional 8%–12% of the negative age effect on initial flight performance. Discussion. IIV plays an important role in real-world tasks and is another aspect of cognition that underlies age-related differences in cognitive performance. PMID:23052365

  16. Intraindividual variability in basic reaction time predicts middle-aged and older pilots' flight simulator performance.

    Science.gov (United States)

    Kennedy, Quinn; Taylor, Joy; Heraldez, Daniel; Noda, Art; Lazzeroni, Laura C; Yesavage, Jerome

    2013-07-01

    Intraindividual variability (IIV) is negatively associated with cognitive test performance and is positively associated with age and some neurological disorders. We aimed to extend these findings to a real-world task, flight simulator performance. We hypothesized that IIV predicts poorer initial flight performance and increased rate of decline in performance among middle-aged and older pilots. Two-hundred and thirty-six pilots (40-69 years) completed annual assessments comprising a cognitive battery and two 75-min simulated flights in a flight simulator. Basic and complex IIV composite variables were created from measures of basic reaction time and shifting and divided attention tasks. Flight simulator performance was characterized by an overall summary score and scores on communication, emergencies, approach, and traffic avoidance components. Although basic IIV did not predict rate of decline in flight performance, it had a negative association with initial performance for most flight measures. After taking into account processing speed, basic IIV explained an additional 8%-12% of the negative age effect on initial flight performance. IIV plays an important role in real-world tasks and is another aspect of cognition that underlies age-related differences in cognitive performance.

  17. Urinary Metabolomics Identifies a Molecular Correlate of Interstitial Cystitis/Bladder Pain Syndrome in a Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP Research Network Cohort

    Directory of Open Access Journals (Sweden)

    Kaveri S. Parker

    2016-05-01

    Full Text Available Interstitial cystitis/bladder pain syndrome (IC/BPS is a poorly understood syndrome affecting up to 6.5% of adult women in the U.S. The lack of broadly accepted objective laboratory markers for this condition hampers efforts to diagnose and treat this condition. To identify biochemical markers for IC/BPS, we applied mass spectrometry-based global metabolite profiling to urine specimens from a cohort of female IC/BPS subjects from the Multidisciplinary Approach to the Study of Chronic Pelvic Pain (MAPP Research Network. These analyses identified multiple metabolites capable of discriminating IC/BPS and control subjects. Of these candidate markers, etiocholan-3α-ol-17-one sulfate (Etio-S, a sulfoconjugated 5-β reduced isomer of testosterone, distinguished female IC/BPS and control subjects with a sensitivity and specificity >90%. Among IC/BPS subjects, urinary Etio-S levels are correlated with elevated symptom scores (symptoms, pelvic pain, and number of painful body sites and could resolve high- from low-symptom IC/BPS subgroups. Etio-S-associated biochemical changes persisted through 3–6 months of longitudinal follow up. These results raise the possibility that an underlying biochemical abnormality contributes to symptoms in patients with severe IC/BPS.

  18. In Patients With Cirrhosis, Driving Simulator Performance Is Associated With Real-life Driving.

    Science.gov (United States)

    Lauridsen, Mette M; Thacker, Leroy R; White, Melanie B; Unser, Ariel; Sterling, Richard K; Stravitz, Richard T; Matherly, Scott; Puri, Puneet; Sanyal, Arun J; Gavis, Edith A; Luketic, Velimir; Siddiqui, Muhammad S; Heuman, Douglas M; Fuchs, Michael; Bajaj, Jasmohan S

    2016-05-01

    Minimal hepatic encephalopathy (MHE) has been linked to higher real-life rates of automobile crashes and poor performance in driving simulation studies, but the link between driving simulator performance and real-life automobile crashes has not been clearly established. Furthermore, not all patients with MHE are unsafe drivers, but it is unclear how to distinguish them from unsafe drivers. We investigated the link between performance on driving simulators and real-life automobile accidents and traffic violations. We also aimed to identify features of unsafe drivers with cirrhosis and evaluated changes in simulated driving skills and MHE status after 1 year. We performed a study of outpatients with cirrhosis (n = 205; median 55 years old; median model for end-stage liver disease score, 9.5; none with overt hepatic encephalopathy or alcohol or illicit drug use within previous 6 months) seen at the Virginia Commonwealth University and McGuire Veterans Administration Medical Center, from November 2008 through April 2014. All participants were given paper-pencil tests to diagnose MHE (98 had MHE; 48%), and 163 patients completed a standardized driving simulation. Data were collected on traffic violations and automobile accidents from the Virginia Department of Motor Vehicles and from participants' self-assessments when they entered the study, and from 73 participants 1 year later. Participants also completed a questionnaire about alcohol use and cessation patterns. The driving simulator measured crashes, run-time, road center and edge excursions, and illegal turns during navigation; before and after each driving simulation session, patients were asked to rate their overall driving skills. Drivers were classified as safe or unsafe based on crashes and violations reported on official driving records; simulation results were compared with real-life driving records. Multivariable regression analyses of real-life crashes and violations was performed using data on

  19. Computer-based laparoscopic and robotic surgical simulators: performance characteristics and perceptions of new users.

    Science.gov (United States)

    Lin, David W; Romanelli, John R; Kuhn, Jay N; Thompson, Renee E; Bush, Ron W; Seymour, Neal E

    2009-01-01

    This study aimed to define perceptions of the need and the value of new simulation devices for laparoscopic and robot-assisted surgery. The initial experience of surgeons using both robotic and nonrobotic laparoscopic simulators to perform an advanced laparoscopic skill was evaluated. At the 2006 Society of American Gastroesophageal Surgeons (SAGES) meeting, 63 Learning Center attendees used a new virtual reality robotic surgery simulator (SEP Robot) and either a computer-enhanced laparoscopic simulator (ProMIS) or a virtual reality simulator (SurgicalSIM). Demographic and training data were collected by an intake survey. Subjects then were assessed during one iteration of laparoscopic suturing and knot-tying on the SEP Robot and either the ProMIS or the SurgicalSIM. A posttask survey determined users' impressions of task realism, interface quality, and educational value. Performance data were collected and comparisons made between user-defined groups, different simulation platforms, and posttask survey responses. The task completion rate was significantly greater for experts than for nonexperts on the virtual reality platforms (SurgicalSIM: 100% vs 36%; SEP Robot: 93% vs 63%; p platforms, whereas simulator metrics best discriminated expertise for the videoscopic platform. Similar comparisons for the virtual reality platforms were not feasible because of the low task completion rate for nonexperts. The added degrees of freedom associated with the robotic surgical simulator instruments facilitated completion of the task by nonexperts. All platforms were perceived as effective training tools.

  20. Improved performance of maternal-fetal medicine staff after maternal cardiac arrest simulation-based training.

    Science.gov (United States)

    Fisher, Nelli; Eisen, Lewis A; Bayya, Jyothshna V; Dulu, Alina; Bernstein, Peter S; Merkatz, Irwin R; Goffman, Dena

    2011-09-01

    To determine the impact of simulation-based maternal cardiac arrest training on performance, knowledge, and confidence among Maternal-Fetal Medicine staff. Maternal-Fetal Medicine staff (n = 19) participated in a maternal arrest simulation program. Based on evaluation of performance during initial simulations, an intervention was designed including: basic life support course, advanced cardiac life support pregnancy modification lecture, and simulation practice. Postintervention evaluative simulations were performed. All simulations included a knowledge test, confidence survey, and debriefing. A checklist with 9 pregnancy modification (maternal) and 16 critical care (25 total) tasks was used for scoring. Postintervention scores reflected statistically significant improvement. Maternal-Fetal Medicine staff demonstrated statistically significant improvement in timely initiation of cardiopulmonary resuscitation (120 vs 32 seconds, P = .042) and cesarean delivery (240 vs 159 seconds, P = .017). Prompt cardiopulmonary resuscitation initiation and pregnancy modifications application are critical in maternal and fetal survival during cardiac arrest. Simulation is a useful tool for Maternal-Fetal Medicine staff to improve skills, knowledge, and confidence in the management of this catastrophic event. Published by Mosby, Inc.

  1. Rapid prototyping in order to improve building performance simulation for detailed design support

    NARCIS (Netherlands)

    Hopfe, C.J.; Hensen, J.L.M.; Stankov, P.

    2006-01-01

    Building performance simulation (BPS) is a powerful tool to support building and system designers in emulating how orientation, building type, HVAC system etc. interacts the overall building performance. Currently BPS is used only for code compliance in the detailed design, neither to make informed

  2. Sustained effect of simulation-based ultrasound training on clinical performance

    DEFF Research Database (Denmark)

    Tolsgaard, M G; Ringsted, C; Dreisler, E

    2015-01-01

    on a virtual-reality transvaginal ultrasound simulator until an expert performance level was attained followed by training on a pelvic mannequin. After two months of clinical training, one transvaginal ultrasound scan was recorded for assessment of participants' clinical performance. Two blinded ultrasound...

  3. Integrating Soft Set Theory and Fuzzy Linguistic Model to Evaluate the Performance of Training Simulation Systems.

    Science.gov (United States)

    Chang, Kuei-Hu; Chang, Yung-Chia; Chain, Kai; Chung, Hsiang-Yu

    2016-01-01

    The advancement of high technologies and the arrival of the information age have caused changes to the modern warfare. The military forces of many countries have replaced partially real training drills with training simulation systems to achieve combat readiness. However, considerable types of training simulation systems are used in military settings. In addition, differences in system set up time, functions, the environment, and the competency of system operators, as well as incomplete information have made it difficult to evaluate the performance of training simulation systems. To address the aforementioned problems, this study integrated analytic hierarchy process, soft set theory, and the fuzzy linguistic representation model to evaluate the performance of various training simulation systems. Furthermore, importance-performance analysis was adopted to examine the influence of saving costs and training safety of training simulation systems. The findings of this study are expected to facilitate applying military training simulation systems, avoiding wasting of resources (e.g., low utility and idle time), and providing data for subsequent applications and analysis. To verify the method proposed in this study, the numerical examples of the performance evaluation of training simulation systems were adopted and compared with the numerical results of an AHP and a novel AHP-based ranking technique. The results verified that not only could expert-provided questionnaire information be fully considered to lower the repetition rate of performance ranking, but a two-dimensional graph could also be used to help administrators allocate limited resources, thereby enhancing the investment benefits and training effectiveness of a training simulation system.

  4. Using simulation to evaluate the performance of resilience strategies and process failures

    Energy Technology Data Exchange (ETDEWEB)

    Levy, Scott N.; Topp, Bryan Embry; Arnold, Dorian C; Ferreira, Kurt Brian; Widener, Patrick; Hoefler, Torsten

    2014-01-01

    Fault-tolerance has been identified as a major challenge for future extreme-scale systems. Current predictions suggest that, as systems grow in size, failures will occur more frequently. Because increases in failure frequency reduce the performance and scalability of these systems, significant effort has been devoted to developing and refining resilience mechanisms to mitigate the impact of failures. However, effective evaluation of these mechanisms has been challenging. Current systems are smaller and have significantly different architectural features (e.g., interconnect, persistent storage) than we expect to see in next-generation systems. To overcome these challenges, we propose the use of simulation. Simulation has been shown to be an effective tool for investigating performance characteristics of applications on future systems. In this work, we: identify the set of system characteristics that are necessary for accurate performance prediction of resilience mechanisms for HPC systems and applications; demonstrate how these system characteristics can be incorporated into an existing large-scale simulator; and evaluate the predictive performance of our modified simulator. We also describe how we were able to optimize the simulator for large temporal and spatial scales-allowing the simulator to run 4x faster and use over 100x less memory.

  5. Transient performance simulation of aircraft engine integrated with fuel and control systems

    International Nuclear Information System (INIS)

    Wang, C.; Li, Y.G.; Yang, B.Y.

    2017-01-01

    Highlights: • A new performance simulation method for engine hydraulic fuel systems is introduced. • Time delay of engine performance due to fuel system model is noticeable but small. • The method provides details of fuel system behavior in engine transient processes. • The method could be used to support engine and fuel system designs. - Abstract: A new method for the simulation of gas turbine fuel systems based on an inter-component volume method has been developed. It is able to simulate the performance of each of the hydraulic components of a fuel system using physics-based models, which potentially offers more accurate results compared with those using transfer functions. A transient performance simulation system has been set up for gas turbine engines based on an inter-component volume (ICV) method. A proportional-integral (PI) control strategy is used for the simulation of engine controller. An integrated engine and its control and hydraulic fuel systems has been set up to investigate their coupling effect during engine transient processes. The developed simulation system has been applied to a model aero engine. The results show that the delay of the engine transient response due to the inclusion of the fuel system model is noticeable although relatively small. The developed method is generic and can be applied to any other gas turbines and their control and fuel systems.

  6. The Drive-Wise Project: Driving Simulator Training increases real driving performance in healthy older drivers

    Directory of Open Access Journals (Sweden)

    Gianclaudio eCasutt

    2014-05-01

    Full Text Available Background: Age-related cognitive decline is often associated with unsafe driving behavior. We hypothesized that 10 active training sessions in a driving simulator increase cognitive and on-road driving performance. In addition, driving simulator training should outperform cognitive training.Methods: Ninety-one healthy active drivers (62 – 87 years were randomly assigned to either (1 a driving simulator training group, (2 an attention training group (vigilance and selective attention, or (3 a control group. The main outcome variables were on-road driving and cognitive performance. Seventy-seven participants (85% completed the training and were included in the analyses. Training gains were analyzed using a multiple regression analysis with planned comparisons.Results: The driving simulator training group showed an improvement in on-road driving performance compared to the attention training group. In addition, both training groups increased cognitive performance compared to the control group. Conclusion: Driving simulator training offers the potential to enhance driving skills in older drivers. Compared to the attention training, the simulator training seems to be a more powerful program for increasing older drivers’ safety on the road.

  7. Performance of the general circulation models in simulating temperature and precipitation over Iran

    Science.gov (United States)

    Abbasian, Mohammadsadegh; Moghim, Sanaz; Abrishamchi, Ahmad

    2018-03-01

    General Circulation Models (GCMs) are advanced tools for impact assessment and climate change studies. Previous studies show that the performance of the GCMs in simulating climate variables varies significantly over different regions. This study intends to evaluate the performance of the Coupled Model Intercomparison Project phase 5 (CMIP5) GCMs in simulating temperature and precipitation over Iran. Simulations from 37 GCMs and observations from the Climatic Research Unit (CRU) were obtained for the period of 1901-2005. Six measures of performance including mean bias, root mean square error (RMSE), Nash-Sutcliffe efficiency (NSE), linear correlation coefficient (r), Kolmogorov-Smirnov statistic (KS), Sen's slope estimator, and the Taylor diagram are used for the evaluation. GCMs are ranked based on each statistic at seasonal and annual time scales. Results show that most GCMs perform reasonably well in simulating the annual and seasonal temperature over Iran. The majority of the GCMs have a poor skill to simulate precipitation, particularly at seasonal scale. Based on the results, the best GCMs to represent temperature and precipitation simulations over Iran are the CMCC-CMS (Euro-Mediterranean Center on Climate Change) and the MRI-CGCM3 (Meteorological Research Institute), respectively. The results are valuable for climate and hydrometeorological studies and can help water resources planners and managers to choose the proper GCM based on their criteria.

  8. Comparative Performance of Four Single Extreme Outlier Discordancy Tests from Monte Carlo Simulations

    Directory of Open Access Journals (Sweden)

    Surendra P. Verma

    2014-01-01

    Full Text Available Using highly precise and accurate Monte Carlo simulations of 20,000,000 replications and 102 independent simulation experiments with extremely low simulation errors and total uncertainties, we evaluated the performance of four single outlier discordancy tests (Grubbs test N2, Dixon test N8, skewness test N14, and kurtosis test N15 for normal samples of sizes 5 to 20. Statistical contaminations of a single observation resulting from parameters called δ from ±0.1 up to ±20 for modeling the slippage of central tendency or ε from ±1.1 up to ±200 for slippage of dispersion, as well as no contamination (δ=0 and ε=±1, were simulated. Because of the use of precise and accurate random and normally distributed simulated data, very large replications, and a large number of independent experiments, this paper presents a novel approach for precise and accurate estimations of power functions of four popular discordancy tests and, therefore, should not be considered as a simple simulation exercise unrelated to probability and statistics. From both criteria of the Power of Test proposed by Hayes and Kinsella and the Test Performance Criterion of Barnett and Lewis, Dixon test N8 performs less well than the other three tests. The overall performance of these four tests could be summarized as N2≅N15>N14>N8.

  9. Test plan for Fauske and Associates to perform tube propagation experiments with simulated Hanford tank wastes

    International Nuclear Information System (INIS)

    Carlson, C.D.; Babad, H.

    1996-05-01

    This test plan, prepared at Pacific Northwest National Laboratory for Westinghouse Hanford Company, provides guidance for performing tube propagation experiments on simulated Hanford tank wastes and on actual tank waste samples. Simulant compositions are defined and an experimental logic tree is provided for Fauske and Associates (FAI) to perform the experiments. From this guidance, methods and equipment for small-scale tube propagation experiments to be performed at the Hanford Site on actual tank samples will be developed. Propagation behavior of wastes will directly support the safety analysis (SARR) for the organic tanks. Tube propagation may be the definitive tool for determining the relative reactivity of the wastes contained in the Hanford tanks. FAI have performed tube propagation studies previously on simple two- and three-component surrogate mixtures. The simulant defined in this test plan more closely represents actual tank composition. Data will be used to support preparation of criteria for determining the relative safety of the organic bearing wastes

  10. Computer simulation of steady-state performance of air-to-air heat pumps

    Energy Technology Data Exchange (ETDEWEB)

    Ellison, R D; Creswick, F A

    1978-03-01

    A computer model by which the performance of air-to-air heat pumps can be simulated is described. The intended use of the model is to evaluate analytically the improvements in performance that can be effected by various component improvements. The model is based on a trio of independent simulation programs originated at the Massachusetts Institute of Technology Heat Transfer Laboratory. The three programs have been combined so that user intervention and decision making between major steps of the simulation are unnecessary. The program was further modified by substituting a new compressor model and adding a capillary tube model, both of which are described. Performance predicted by the computer model is shown to be in reasonable agreement with performance data observed in our laboratory. Planned modifications by which the utility of the computer model can be enhanced in the future are described. User instructions and a FORTRAN listing of the program are included.

  11. Use of high performance networks and supercomputers for real-time flight simulation

    Science.gov (United States)

    Cleveland, Jeff I., II

    1993-01-01

    In order to meet the stringent time-critical requirements for real-time man-in-the-loop flight simulation, computer processing operations must be consistent in processing time and be completed in as short a time as possible. These operations include simulation mathematical model computation and data input/output to the simulators. In 1986, in response to increased demands for flight simulation performance, NASA's Langley Research Center (LaRC), working with the contractor, developed extensions to the Computer Automated Measurement and Control (CAMAC) technology which resulted in a factor of ten increase in the effective bandwidth and reduced latency of modules necessary for simulator communication. This technology extension is being used by more than 80 leading technological developers in the United States, Canada, and Europe. Included among the commercial applications are nuclear process control, power grid analysis, process monitoring, real-time simulation, and radar data acquisition. Personnel at LaRC are completing the development of the use of supercomputers for mathematical model computation to support real-time flight simulation. This includes the development of a real-time operating system and development of specialized software and hardware for the simulator network. This paper describes the data acquisition technology and the development of supercomputing for flight simulation.

  12. Simulation training improves medical students' learning experiences when performing real vaginal deliveries.

    Science.gov (United States)

    Dayal, Ashlesha K; Fisher, Nelli; Magrane, Diane; Goffman, Dena; Bernstein, Peter S; Katz, Nadine T

    2009-01-01

    To determine the relationship between simulation training for vaginal delivery maneuvers and subsequent participation in live deliveries during the clinical rotation and to assess medical students' performance and confidence in vaginal delivery maneuvers with and without simulation training. Medical students were randomized to receive or not to receive simulation training for vaginal delivery maneuvers on a mannequin simulator at the start of a 6-week clerkship. Both groups received traditional didactic and clinical teaching. One researcher, blinded to randomization, scored student competence of delivery maneuvers and overall delivery performance on simulator. Delivery performance was scored (1-5, with 5 being the highest) at weeks 1 and 5 of the clerkship. Students were surveyed to assess self-confidence in the ability to perform delivery maneuvers at weeks 1 and 5, and participation in live deliveries was evaluated using student obstetric patient logs. Thirty-three students were randomized, 18 to simulation training [simulation group (SIM)] and 15 to no simulation training [control group (CON)]. Clerkship logs demonstrated that SIM students participated in more deliveries than CON students (9.8 +/- 3.7 versus 6.2 +/- 2.8, P < 0.005). SIM reported increased confidence in ability to perform a vaginal delivery, when compared with CON at the end of the clerkship (3.81 +/- 0.83 versus 3.00 +/- 1.0, respectively, P < 0.05). The overall delivery performance score was significantly higher in SIM, when compared with CON at week 1 (3.94 +/- 0.94 versus 2.07 +/- 1.22, respectively, P < 0.001) and week 5 (4.88 +/- 0.33 versus 4.31 +/- 0.63, P < 0.001) in the simulated environment. Students who receive simulation training participate more actively in the clinical environment during the course of the clerkship. Student simulation training is beneficial to learn obstetric skills in a minimal risk environment, demonstrate competency with maneuvers, and translate this competence

  13. Surrogate model approach for improving the performance of reactive transport simulations

    Science.gov (United States)

    Jatnieks, Janis; De Lucia, Marco; Sips, Mike; Dransch, Doris

    2016-04-01

    Reactive transport models can serve a large number of important geoscientific applications involving underground resources in industry and scientific research. It is common for simulation of reactive transport to consist of at least two coupled simulation models. First is a hydrodynamics simulator that is responsible for simulating the flow of groundwaters and transport of solutes. Hydrodynamics simulators are well established technology and can be very efficient. When hydrodynamics simulations are performed without coupled geochemistry, their spatial geometries can span millions of elements even when running on desktop workstations. Second is a geochemical simulation model that is coupled to the hydrodynamics simulator. Geochemical simulation models are much more computationally costly. This is a problem that makes reactive transport simulations spanning millions of spatial elements very difficult to achieve. To address this problem we propose to replace the coupled geochemical simulation model with a surrogate model. A surrogate is a statistical model created to include only the necessary subset of simulator complexity for a particular scenario. To demonstrate the viability of such an approach we tested it on a popular reactive transport benchmark problem that involves 1D Calcite transport. This is a published benchmark problem (Kolditz, 2012) for simulation models and for this reason we use it to test the surrogate model approach. To do this we tried a number of statistical models available through the caret and DiceEval packages for R, to be used as surrogate models. These were trained on randomly sampled subset of the input-output data from the geochemical simulation model used in the original reactive transport simulation. For validation we use the surrogate model to predict the simulator output using the part of sampled input data that was not used for training the statistical model. For this scenario we find that the multivariate adaptive regression splines

  14. Correspondence between Simulator and On-Road Drive Performance: Implications for Assessment of Driving Safety.

    Science.gov (United States)

    Aksan, Nazan; Hacker, Sarah D; Sager, Lauren; Dawson, Jeffrey; Anderson, Steven; Rizzo, Matthew

    2016-03-01

    Forty-two younger (Mean age = 35) and 37 older drivers (Mean age = 77) completed four similar simulated drives. In addition, 32 younger and 30 older drivers completed a standard on-road drive in an instrumented vehicle. Performance in the simulated drives was evaluated using both electronic drive data and video-review of errors. Safety errors during the on-road drive were evaluated by a certified driving instructor blind to simulator performance, using state Department of Transportation criteria. We examined the degree of convergence in performance across the two platforms on various driving tasks including lane change, lane keeping, speed control, stopping, turns, and overall performance. Differences based on age group indicated a pattern of strong relative validity for simulator measures. However, relative rank-order in specific metrics of performance suggested a pattern of moderate relative validity. The findings have implications for the use of simulators in assessments of driving safety as well as its use in training and/or rehabilitation settings.

  15. Burnout among pilots: psychosocial factors related to happiness and performance at simulator training.

    Science.gov (United States)

    Demerouti, Evangelia; Veldhuis, Wouter; Coombes, Claire; Hunter, Rob

    2018-06-18

    In this study among airline pilots, we aim to uncover the work characteristics (job demands and resources) and the outcomes (job crafting, happiness and simulator training performance) that are related to burnout for this occupational group. Using a large sample of airline pilots, we showed that 40% of the participating pilots experience high burnout. In line with Job Demands-Resources theory, job demands were detrimental for simulator training performance because they made pilots more exhausted and less able to craft their job, whereas job resources had a favourable effect because they reduced feelings of disengagement and increased job crafting. Moreover, burnout was negatively related to pilots' happiness with life. These findings highlight the importance of psychosocial factors and health for valuable outcomes for both pilots and airlines. Practitioner Summary: Using an online survey among the members of a European pilots' professional association, we examined the relationship between psychosocial factors (work characteristics, burnout) and outcomes (simulator training performance, happiness). Forty per cent of the participating pilots experience high burnout. Job demands were detrimental, whereas job resources were favourable for simulator training performance/happiness. Twitter text: 40% of airline pilots experience burnout and psychosocial work factors and burnout relate to performance at pilots' simulator training.

  16. Assessing bimanual performance in brain tumor resection with NeuroTouch, a virtual reality simulator.

    Science.gov (United States)

    Alotaibi, Fahad E; AlZhrani, Gmaan A; Mullah, Muhammad A S; Sabbagh, Abdulrahman J; Azarnoush, Hamed; Winkler-Schwartz, Alexander; Del Maestro, Rolando F

    2015-03-01

    Validated procedures to objectively measure neurosurgical bimanual psychomotor skills are unavailable. The NeuroTouch simulator provides metrics to determine bimanual performance, but validation is essential before implementation of this platform into neurosurgical training, assessment, and curriculum development. To develop, evaluate, and validate neurosurgical bimanual performance metrics for resection of simulated brain tumors with NeuroTouch. Bimanual resection of 8 simulated brain tumors with differing color, stiffness, and border complexity was evaluated. Metrics assessed included blood loss, tumor percentage resected, total simulated normal brain volume removed, total tip path lengths, maximum and sum of forces used by instruments, efficiency index, ultrasonic aspirator path length index, coordination index, and ultrasonic aspirator bimanual forces ratio. Six neurosurgeons and 12 residents (6 senior and 6 junior) were evaluated. Increasing tumor complexity impaired resident bimanual performance significantly more than neurosurgeons. Operating on black vs glioma-colored tumors resulted in significantly higher blood loss and lower tumor percentage, whereas altering tactile cues from hard to soft decreased resident tumor resection. Regardless of tumor complexity, significant differences were found between neurosurgeons, senior residents, and junior residents in efficiency index and ultrasonic aspirator path length index. Ultrasonic aspirator bimanual force ratio outlined significant differences between senior and junior residents, whereas coordination index demonstrated significant differences between junior residents and neurosurgeons. The NeuroTouch platform incorporating the simulated scenarios and metrics used differentiates novice from expert neurosurgical performance, demonstrating NeuroTouch face, content, and construct validity and the possibility of developing brain tumor resection proficiency performance benchmarks.

  17. The Relationship between Tests of Neurocognition and Performance on a Laparoscopic Simulator

    Directory of Open Access Journals (Sweden)

    Oumar Kuzbari

    2010-01-01

    Full Text Available Objective. To estimate if there is a relationship between the results of tests of neurocognition and performance on a laparoscopic surgery simulator. Methods and Materials. Twenty participants with no prior laparoscopic experience had baseline cognitive tests administered (Trail Making Test, Part A and B (TMT-A and TMT-B, Grooved Peg Board Test, Symbol Digit Modalities Test, Symbol Digit Recall Test, and Stroop Interference Test, completed a demographic questionnaire, and then performed laparoscopy using a simulator. We correlated the results of cognitive tests with laparoscopic surgical performance. Results. One cognitive test sensitive to frontal lobe function, TMT-A, significantly correlated with laparoscopic surgical performance on the simulator (correlation coefficient of 0.534 with P<.05. However, the correlation between performance and other cognitive tests (TMT-B, Grooved Peg Board Test, Symbol Digit Modalities Test, Symbol Digit Recall Test, and Stroop Interference Test was not statistically significant. Conclusion. Laparoscopic performance may be related to measures of frontal lobe function. Neurocognitive tests may predict motor skills abilities and performance on laparoscopic simulator.

  18. Aging analysis of high performance FinFET flip-flop under Dynamic NBTI simulation configuration

    Science.gov (United States)

    Zainudin, M. F.; Hussin, H.; Halim, A. K.; Karim, J.

    2018-03-01

    A mechanism known as Negative-bias Temperature Instability (NBTI) degrades a main electrical parameters of a circuit especially in terms of performance. So far, the circuit design available at present are only focussed on high performance circuit without considering the circuit reliability and robustness. In this paper, the main circuit performances of high performance FinFET flip-flop such as delay time, and power were studied with the presence of the NBTI degradation. The aging analysis was verified using a 16nm High Performance Predictive Technology Model (PTM) based on different commands available at Synopsys HSPICE. The results shown that the circuit under the longer dynamic NBTI simulation produces the highest impact in the increasing of gate delay and decrease in the average power reduction from a fresh simulation until the aged stress time under a nominal condition. In addition, the circuit performance under a varied stress condition such as temperature and negative stress gate bias were also studied.

  19. Assessing the performance and satisfaction of medical residents utilizing standardized patient versus mannequin-simulated training

    Directory of Open Access Journals (Sweden)

    Alsaad AA

    2017-07-01

    Full Text Available Ali A Alsaad,1 Swetha Davuluri,2 Vandana Y Bhide,3 Amy M Lannen,4 Michael J Maniaci3 1Department of Internal Medicine, Mayo Clinic, 2University of Miami, Coral Gables, 3Division of Hospital Internal Medicine, 4J. Wayne and Delores Barr Weaver Simulation Center, Mayo Clinic, Jacksonville, FL, USA Background: Conducting simulations of rapidly decompensating patients are a key part of internal medicine (IM residency training. Traditionally, mannequins have been the simulation tool used in these scenarios. Objective: To compare IM residents’ performance and assess realism in specific-simulated decompensating patient scenarios using standardized patients (SPs as compared to mannequin. Methods: Nineteen IM residents were randomized to undergo simulations using either a mannequin or an SP. Each resident in the two groups underwent four different simulation scenarios (calcium channel blocker overdose, severe sepsis, severe asthma exacerbation, and acute bacterial meningitis. Residents completed pretest and post-test evaluations as well as a questionnaire to assess the reality perception (realism score. Results: Nine residents completed mannequin-based scenarios, whereas 10 completed SP-based scenarios. Improvement in the post-test scores was seen in both groups. However, there were significantly higher post-test scores achieved with SP simulations in three out of the four scenarios (P=0.01. When compared with the mannequin group, the SP simulation group showed a significantly higher average realism score (P=0.002. Conclusions: Applying SP-based specific-simulation scenarios in IM residency training may result in better performance and a higher sense of a realistic experience by medical residents. Keywords: simulation, standardized patient, satisfaction, mannequin, assessment, resident education

  20. Simulation of the job processing performance at an ALICE Tier-2 site with MONARC

    International Nuclear Information System (INIS)

    Zach, C; Adamová, D; Betev, L

    2011-01-01

    The MONARC (MOdels of Networked Analysis at Regional Centers) framework has been developed and designed with the aim to provide a tool for realistic simulations of large scale distributed computing systems, with a special focus on the Grid systems of the experiments at the CERN LHC. In this paper, we describe a usage of the MONARC framework and tools for a simulation of the job processing performance at an ALICE Tier-2 site.

  1. Etude par simulation hil des performances d'un statcom pour la ...

    African Journals Online (AJOL)

    Ce travail présente l'étude par simulation Hardware In the Loop (HIL) des performances d'un STATCOM pour la stabilisation de la tension délivrée par une génératrice asynchrone triphasée auto excitée dans un réseau autonome. Nous avons combiné l'utilisation du logiciel de simulation LABVIEW et la carte ARDUINO ...

  2. Dynamic simulation platform to verify the performance of the reactor regulating system for a research reactor

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2015-07-01

    Digital instrumentation and controls system technique is being introduced in new constructed research reactor or life extension of older research reactor. Digital systems are easy to change and optimize but the validated process for them is required. Also, to reduce project risk or cost, we have to make it sure that configuration and control functions is right before the commissioning phase on research reactor. For this purpose, simulators have been widely used in developing control systems in automotive and aerospace industries. In these literatures, however, very few of these can be found regarding test on the control system of research reactor with simulator. Therefore, this paper proposes a simulation platform to verify the performance of RRS (Reactor Regulating System) for research reactor. This simulation platform consists of the reactor simulation model and the interface module. This simulation platform is applied to I and C upgrade project of TRIGA reactor, and many problems of RRS configuration were found and solved. And it proved that the dynamic performance testing based on simulator enables significant time saving and improves economics and quality for RRS in the system test phase. (authors)

  3. High-Fidelity Simulation in Occupational Therapy Curriculum: Impact on Level II Fieldwork Performance

    Directory of Open Access Journals (Sweden)

    Rebecca Ozelie

    2016-10-01

    Full Text Available Simulation experiences provide experiential learning opportunities during artificially produced real-life medical situations in a safe environment. Evidence supports using simulation in health care education yet limited quantitative evidence exists in occupational therapy. This study aimed to evaluate the differences in scores on the AOTA Fieldwork Performance Evaluation for the Occupational Therapy Student of Level II occupational therapy students who received high-fidelity simulation training and students who did not. A retrospective analysis of 180 students from a private university was used. Independent samples nonparametric t tests examined mean differences between Fieldwork Performance Evaluation scores of those who did and did not receive simulation experiences in the curriculum. Mean ranks were also analyzed for subsection scores and practice settings. Results of this study found no significant difference in overall Fieldwork Performance Evaluation scores between the two groups. The students who completed simulation and had fieldwork in inpatient rehabilitation had the greatest increase in mean rank scores and increases in several subsections. The outcome measure used in this study was found to have limited discriminatory capability and may have affected the results; however, this study finds that using simulation may be a beneficial supplement to didactic coursework in occupational therapy curriculums.

  4. 3D numerical simulation on heat transfer performance of a cylindrical liquid immersion solar receiver

    International Nuclear Information System (INIS)

    Xiang Haijun; Wang Yiping; Zhu Li; Han Xinyue; Sun Yong; Zhao Zhengjian

    2012-01-01

    Highlights: ► Establishment of a three-dimensional numerical simulation model of a cylindrical liquid immersion solar receiver. ► Determination of model parameters and validation of the model by using the real-collected data. ► Optimization of liquid flow rate and fin’s structure for better heat transfer performance. - Abstract: Liquid immersion cooling for a cylindrical solar receiver in a dish concentrator photovoltaic system has been experimentally verified to be a promising method of removing surplus heat from densely packed solar cells. In the present study, a three-dimensional (3D) numerical simulation model of the prototype was established for better understanding the mechanism of the direct-contact heat transfer process. With the selection of standard k–ε turbulent model, the detailed simulation results of velocity field and temperature characteristics were obtained. The heat transfer performance of two structural modules (bare module and finned module) under actual weather conditions was simulated. It was found that the predicted temperature distribution of the two structural modules at the axial and lateral direction was in good agreement with the experimental data. Based on the validated simulation model, the influence of liquid flow rate and module geometric parameters on the cell temperature was then investigated. The simulated results indicated that the cell module with fin height of 4 mm and fin number of 11 has the best heat transfer performance and will be used in further works.

  5. An applied artificial intelligence approach towards assessing building performance simulation tools

    Energy Technology Data Exchange (ETDEWEB)

    Yezioro, Abraham [Faculty of Architecture and Town Planning, Technion IIT (Israel); Dong, Bing [Center for Building Performance and Diagnostics, School of Architecture, Carnegie Mellon University (United States); Leite, Fernanda [Department of Civil and Environmental Engineering, Carnegie Mellon University (United States)

    2008-07-01

    With the development of modern computer technology, a large amount of building energy simulation tools is available in the market. When choosing which simulation tool to use in a project, the user must consider the tool's accuracy and reliability, considering the building information they have at hand, which will serve as input for the tool. This paper presents an approach towards assessing building performance simulation results to actual measurements, using artificial neural networks (ANN) for predicting building energy performance. Training and testing of the ANN were carried out with energy consumption data acquired for 1 week in the case building called the Solar House. The predicted results show a good fitness with the mathematical model with a mean absolute error of 0.9%. Moreover, four building simulation tools were selected in this study in order to compare their results with the ANN predicted energy consumption: Energy{sub 1}0, Green Building Studio web tool, eQuest and EnergyPlus. The results showed that the more detailed simulation tools have the best simulation performance in terms of heating and cooling electricity consumption within 3% of mean absolute error. (author)

  6. A virtual reality endoscopic simulator augments general surgery resident cancer education as measured by performance improvement.

    Science.gov (United States)

    White, Ian; Buchberg, Brian; Tsikitis, V Liana; Herzig, Daniel O; Vetto, John T; Lu, Kim C

    2014-06-01

    Colorectal cancer is the second most common cause of death in the USA. The need for screening colonoscopies, and thus adequately trained endoscopists, particularly in rural areas, is on the rise. Recent increases in required endoscopic cases for surgical resident graduation by the Surgery Residency Review Committee (RRC) further emphasize the need for more effective endoscopic training during residency to determine if a virtual reality colonoscopy simulator enhances surgical resident endoscopic education by detecting improvement in colonoscopy skills before and after 6 weeks of formal clinical endoscopic training. We conducted a retrospective review of prospectively collected surgery resident data on an endoscopy simulator. Residents performed four different clinical scenarios on the endoscopic simulator before and after a 6-week endoscopic training course. Data were collected over a 5-year period from 94 different residents performing a total of 795 colonoscopic simulation scenarios. Main outcome measures included time to cecal intubation, "red out" time, and severity of simulated patient discomfort (mild, moderate, severe, extreme) during colonoscopy scenarios. Average time to intubation of the cecum was 6.8 min for those residents who had not undergone endoscopic training versus 4.4 min for those who had undergone endoscopic training (p Virtual reality endoscopic simulation is an effective tool for both augmenting surgical resident endoscopy cancer education and measuring improvement in resident performance after formal clinical endoscopic training.

  7. Performance of technology-driven simulators for medical students--a systematic review.

    Science.gov (United States)

    Michael, Michael; Abboudi, Hamid; Ker, Jean; Shamim Khan, Mohammed; Dasgupta, Prokar; Ahmed, Kamran

    2014-12-01

    Simulation-based education has evolved as a key training tool in high-risk industries such as aviation and the military. In parallel with these industries, the benefits of incorporating specialty-oriented simulation training within medical schools are vast. Adoption of simulators into medical school education programs has shown great promise and has the potential to revolutionize modern undergraduate education. An English literature search was carried out using MEDLINE, EMBASE, and psychINFO databases to identify all randomized controlled studies pertaining to "technology-driven" simulators used in undergraduate medical education. A validity framework incorporating the "framework for technology enhanced learning" report by the Department of Health, United Kingdom, was used to evaluate the capabilities of each technology-driven simulator. Information was collected regarding the simulator type, characteristics, and brand name. Where possible, we extracted information from the studies on the simulators' performance with respect to validity status, reliability, feasibility, education impact, acceptability, and cost effectiveness. We identified 19 studies, analyzing simulators for medical students across a variety of procedure-based specialities including; cardiovascular (n = 2), endoscopy (n = 3), laparoscopic surgery (n = 8), vascular access (n = 2), ophthalmology (n = 1), obstetrics and gynecology (n = 1), anesthesia (n = 1), and pediatrics (n = 1). Incorporation of simulators has so far been on an institutional level; no national or international trends have yet emerged. Simulators are capable of providing a highly educational and realistic experience for the medical students within a variety of speciality-oriented teaching sessions. Further research is needed to establish how best to incorporate simulators into a more primary stage of medical education; preclinical and clinical undergraduate medicine. Copyright © 2014 Elsevier Inc. All rights

  8. An accurate behavioral model for single-photon avalanche diode statistical performance simulation

    Science.gov (United States)

    Xu, Yue; Zhao, Tingchen; Li, Ding

    2018-01-01

    An accurate behavioral model is presented to simulate important statistical performance of single-photon avalanche diodes (SPADs), such as dark count and after-pulsing noise. The derived simulation model takes into account all important generation mechanisms of the two kinds of noise. For the first time, thermal agitation, trap-assisted tunneling and band-to-band tunneling mechanisms are simultaneously incorporated in the simulation model to evaluate dark count behavior of SPADs fabricated in deep sub-micron CMOS technology. Meanwhile, a complete carrier trapping and de-trapping process is considered in afterpulsing model and a simple analytical expression is derived to estimate after-pulsing probability. In particular, the key model parameters of avalanche triggering probability and electric field dependence of excess bias voltage are extracted from Geiger-mode TCAD simulation and this behavioral simulation model doesn't include any empirical parameters. The developed SPAD model is implemented in Verilog-A behavioral hardware description language and successfully operated on commercial Cadence Spectre simulator, showing good universality and compatibility. The model simulation results are in a good accordance with the test data, validating high simulation accuracy.

  9. Clinical simulation training improves the clinical performance of Chinese medical students

    Directory of Open Access Journals (Sweden)

    Ming-ya Zhang

    2015-10-01

    Full Text Available Background: Modern medical education promotes medical students’ clinical operating capacity rather than the mastery of theoretical knowledge. To accomplish this objective, clinical skill training using various simulations was introduced into medical education to cultivate creativity and develop the practical ability of students. However, quantitative analysis of the efficiency of clinical skill training with simulations is lacking. Methods: In the present study, we compared the mean scores of medical students (Jinan University who graduated in 2013 and 2014 on 16 stations between traditional training (control and simulative training groups. In addition, in a clinical skill competition, the objective structured clinical examination (OSCE scores of participating medical students trained using traditional and simulative training were compared. The data were statistically analyzed and qualitatively described. Results: The results revealed that simulative training could significantly enhance the graduate score of medical students compared with the control. The OSCE scores of participating medical students in the clinical skill competition, trained using simulations, were dramatically higher than those of students trained through traditional methods, and we also observed that the OSCE marks were significantly increased for the same participant after simulative training for the clinical skill competition. Conclusions: Taken together, these data indicate that clinical skill training with a variety of simulations could substantially promote the clinical performance of medical students and optimize the resources used for medical education, although a precise analysis of each specialization is needed in the future.

  10. Performance simulation of an absorption heat transformer operating with partially miscible mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Alonso, D.; Cachot, T.; Hornut, J.M. [LSGC-CNRS-ENSIC, Nancy (France); Univ. Henri Poincare, Nancy (France). IUT

    2002-07-08

    This paper proposes to study the thermodynamics performances of a new absorption heat-transformer cycle, where the separation step is obtained by the cooling and settling of a partially miscible mixture at low temperature. This new cycle has been called an absorption-demixing heat transformer (ADHT) cycle. A numerical simulation code has been written, and has allowed us to evaluate the temperature lift and thermal yield of 2 working pairs. Both high qualitative and quantitative performances have been obtained, so demonstrating the feasibility and industrial interest for such a cycle. Moreover a comparison of the simulation results with performances really obtained on an experimental ADHT has confirmed the pertinence of the simulation code.(author)

  11. Lessons from Monte Carlo simulations of the performance of a dual-readout fiber calorimeter

    CERN Document Server

    Akchurin, N; Cardini, A; Cascella, M; De Pedis, D; Ferrari, R; Fracchia, S; Franchino, S; Fraternali, M; Gaudio, G; Genova, P; Hauptman, J; La Rotonda, L; Lee, S; Livan, M; Meoni, E; Pinci, D; Policicchio, A; Saraiva, J G; Scuri, F; Sill, A; Venturelli, T; Wigmans, R

    2014-01-01

    The RD52 calorimeter uses the dual-readout principle to detect both electromagnetic and hadronic showers, as well as muons. Scintillation and Cherenkov light provide the two signals which, in combination, allow for superior hadronic performance. In this paper, we report on detailed, GEANT4 based Monte Carlo simulations of the performance of this instrument. The results of these simulations are compared in great detail to measurements that have been carried out and published by the DREAM Collaboration. This comparison makes it possible to understand subtle details of the shower development in this unusual particle detector. It also allows for predictions of the improvement in the performance that may be expected for larger detectors of this type. These studies also revealed some inadequacies in the GEANT4 simulation packages, especially for hadronic showers, but also for the Cherenkov signals from electromagnetic showers.

  12. Doctors' stress responses and poor communication performance in simulated bad-news consultations.

    Science.gov (United States)

    Brown, Rhonda; Dunn, Stewart; Byrnes, Karen; Morris, Richard; Heinrich, Paul; Shaw, Joanne

    2009-11-01

    No studies have previously evaluated factors associated with high stress levels and poor communication performance in breaking bad news (BBN) consultations. This study determined factors that were most strongly related to doctors' stress responses and poor communication performance during a simulated BBN task. In 2007, the authors recruited 24 doctors comprising 12 novices (i.e., interns/residents with 1-3 years' experience) and 12 experts (i.e., registrars, medical/radiation oncologists, or cancer surgeons, with more than 4 years' experience). Doctors participated in simulated BBN consultations and a number of control tasks. Five-minute-epoch heart rate (HR), HR variability, and communication performance were assessed in all participants. Subjects also completed a short questionnaire asking about their prior experience BBN, perceived stress, psychological distress (i.e., anxiety, depression), fatigue, and burnout. High stress responses were related to inexperience with BBN, fatigue, and giving bad versus good news. Poor communication performance in the consultation was related to high burnout and fatigue scores. These results suggest that BBN was a stressful experience for doctors even in a simulated encounter, especially for those who were inexperienced and/or fatigued. Poor communication performance was related to burnout and fatigue, but not inexperience with BBN. These results likely indicate that burnout and fatigue contributed to stress and poor work performance in some doctors during the simulated BBN task.

  13. Bimanual Psychomotor Performance in Neurosurgical Resident Applicants Assessed Using NeuroTouch, a Virtual Reality Simulator.

    Science.gov (United States)

    Winkler-Schwartz, Alexander; Bajunaid, Khalid; Mullah, Muhammad A S; Marwa, Ibrahim; Alotaibi, Fahad E; Fares, Jawad; Baggiani, Marta; Azarnoush, Hamed; Zharni, Gmaan Al; Christie, Sommer; Sabbagh, Abdulrahman J; Werthner, Penny; Del Maestro, Rolando F

    Current selection methods for neurosurgical residents fail to include objective measurements of bimanual psychomotor performance. Advancements in computer-based simulation provide opportunities to assess cognitive and psychomotor skills in surgically naive populations during complex simulated neurosurgical tasks in risk-free environments. This pilot study was designed to answer 3 questions: (1) What are the differences in bimanual psychomotor performance among neurosurgical residency applicants using NeuroTouch? (2) Are there exceptionally skilled medical students in the applicant cohort? and (3) Is there an influence of previous surgical exposure on surgical performance? Participants were instructed to remove 3 simulated brain tumors with identical visual appearance, stiffness, and random bleeding points. Validated tier 1, tier 2, and advanced tier 2 metrics were used to assess bimanual psychomotor performance. Demographic data included weeks of neurosurgical elective and prior operative exposure. This pilot study was carried out at the McGill Neurosurgical Simulation Research and Training Center immediately following neurosurgical residency interviews at McGill University, Montreal, Canada. All 17 medical students interviewed were asked to participate, of which 16 agreed. Performances were clustered in definable top, middle, and bottom groups with significant differences for all metrics. Increased time spent playing music, increased applicant self-evaluated technical skills, high self-ratings of confidence, and increased skin closures statistically influenced performance on univariate analysis. A trend for both self-rated increased operating room confidence and increased weeks of neurosurgical exposure to increased blood loss was seen in multivariate analysis. Simulation technology identifies neurosurgical residency applicants with differing levels of technical ability. These results provide information for studies being developed for longitudinal studies on the

  14. Simulator training and non-technical factors improve laparoscopic performance among OBGYN trainees.

    Science.gov (United States)

    Ahlborg, Liv; Hedman, Leif; Nisell, Henry; Felländer-Tsai, Li; Enochsson, Lars

    2013-10-01

    To investigate how simulator training and non-technical factors affect laparoscopic performance among residents in obstetrics and gynecology. In this prospective study, trainees were randomized into three groups. The first group was allocated to proficiency-based training in the LapSimGyn(®) virtual reality simulator. The second group received additional structured mentorship during subsequent laparoscopies. The third group served as control group. At baseline an operation was performed and visuospatial ability, flow and self-efficacy were assessed. All groups subsequently performed three tubal occlusions. Self-efficacy and flow were assessed before and/or after each operation. Simulator training was conducted at the Center for Advanced Medical Simulation and Training, Karolinska University Hospital. Sterilizations were performed at each trainee's home clinic. Twenty-eight trainees/residents from 21 hospitals in Sweden were included. Visuospatial ability was tested by the Mental Rotation Test-A. Flow and self-efficacy were assessed by validated scales and questionnaires. Laparoscopic performance was measured as the duration of surgery. Visuospatial ability, self-efficacy and flow were correlated to the laparoscopic performance using Spearman's correlations. Differences between groups were analyzed by the Mann-Whitney U-test. No differences across groups were detected at baseline. Self-efficacy scores before and flow scores after the third operation were significantly higher in the trained groups. Duration of surgery was significantly shorter in the trained groups. Flow and self-efficacy correlate positively with laparoscopic performance. Simulator training and non-technical factors appear to improve the laparoscopic performance among trainees/residents in obstetrics and gynecology. © 2013 Nordic Federation of Societies of Obstetrics and Gynecology.

  15. High-Performance Modeling of Carbon Dioxide Sequestration by Coupling Reservoir Simulation and Molecular Dynamics

    KAUST Repository

    Bao, Kai

    2015-10-26

    The present work describes a parallel computational framework for carbon dioxide (CO2) sequestration simulation by coupling reservoir simulation and molecular dynamics (MD) on massively parallel high-performance-computing (HPC) systems. In this framework, a parallel reservoir simulator, reservoir-simulation toolbox (RST), solves the flow and transport equations that describe the subsurface flow behavior, whereas the MD simulations are performed to provide the required physical parameters. Technologies from several different fields are used to make this novel coupled system work efficiently. One of the major applications of the framework is the modeling of large-scale CO2 sequestration for long-term storage in subsurface geological formations, such as depleted oil and gas reservoirs and deep saline aquifers, which has been proposed as one of the few attractive and practical solutions to reduce CO2 emissions and address the global-warming threat. Fine grids and accurate prediction of the properties of fluid mixtures under geological conditions are essential for accurate simulations. In this work, CO2 sequestration is presented as a first example for coupling reservoir simulation and MD, although the framework can be extended naturally to the full multiphase multicomponent compositional flow simulation to handle more complicated physical processes in the future. Accuracy and scalability analysis are performed on an IBM BlueGene/P and on an IBM BlueGene/Q, the latest IBM supercomputer. Results show good accuracy of our MD simulations compared with published data, and good scalability is observed with the massively parallel HPC systems. The performance and capacity of the proposed framework are well-demonstrated with several experiments with hundreds of millions to one billion cells. To the best of our knowledge, the present work represents the first attempt to couple reservoir simulation and molecular simulation for large-scale modeling. Because of the complexity of

  16. Virtual Reality Simulation as a Tool to Monitor Surgical Performance Indicators: VIRESI Observational Study.

    Science.gov (United States)

    Muralha, Nuno; Oliveira, Manuel; Ferreira, Maria Amélia; Costa-Maia, José

    2017-05-31

    Virtual reality simulation is a topic of discussion as a complementary tool to traditional laparoscopic surgical training in the operating room. However, it is unclear whether virtual reality training can have an impact on the surgical performance of advanced laparoscopic procedures. Our objective was to assess the ability of the virtual reality simulator LAP Mentor to identify and quantify changes in surgical performance indicators, after LAP Mentor training for digestive anastomosis. Twelve surgeons from Centro Hospitalar de São João in Porto (Portugal) performed two sessions of advanced task 5: anastomosis in LAP Mentor, before and after completing the tutorial, and were evaluated on 34 surgical performance indicators. The results show that six surgical performance indicators significantly changed after LAP Mentor training. The surgeons performed the task significantly faster as the median 'total time' significantly reduced (p virtual reality training simulation as a benchmark tool to assess the surgical performance of Portuguese surgeons. LAP Mentor is able to identify variations in surgical performance indicators of digestive anastomosis.

  17. A game theory simulator for assessing the performances of competitive electricity markets

    International Nuclear Information System (INIS)

    Bompard, Ettore; Carpaneto, Enrico; Ciwei, Gao; Napoli, Roberto; Benini, Michele; Gallanti, Massimo; Migliavacca, Gianluigi

    2008-01-01

    In the last years, electricity markets were created all over the world following different basis concepts. Market structure, market rules, demand levels, market concentration and energy sources to produce electricity have a strong influence on market performances. Modifications on these aspects may significantly affect market outcomes. Sensitivity analyses need proper simulation tools. In this paper a medium run electricity market simulator (MREMS) based on game theory is presented. This simulator incorporates two different games, one for the unit commitment of thermal units and one for strategic bidding and hourly market clearing. Either a Forchheimer (one leader) or Bertrand (all player are leaders) or even intermediate model with a whatever number of leaders can be selected, in dependence on the strategic behavior of the producers, allowing for the simulation of markets with different levels of concentration. The simulator was applied to analyse producers' behavior during the first operative year of the Italian power exchange. A comparison between simulation and true market results was carried out in order to test the simulator and validate its simplifying hypotheses. MREMS, yet capable to be used stand-alone, was conceived as the heart of a long-term market simulator (LREMS) allowing to simulate the long-run evolution of the generation park (investments in new plants, refurbishment and dismission of older ones). LREMS is a hierarchic simulator: a long-term ''outer'' game takes yearly investment decisions based on mid-term price projections provided by MREMS. Although this paper is mainly devoted to describe MREMS, one specific section will provide an overview of the ''outer'' game implemented by LREMS. (author)

  18. Effects of incentives on psychosocial performances in simulated space-dwelling groups

    Science.gov (United States)

    Hienz, Robert D.; Brady, Joseph V.; Hursh, Steven R.; Gasior, Eric D.; Spence, Kevin R.; Emurian, Henry H.

    Prior research with individually isolated 3-person crews in a distributed, interactive, planetary exploration simulation examined the effects of communication constraints and crew configuration changes on crew performance and psychosocial self-report measures. The present report extends these findings to a model of performance maintenance that operationalizes conditions under which disruptive affective responses by crew participants might be anticipated to emerge. Experiments evaluated the effects of changes in incentive conditions on crew performance and self-report measures in simulated space-dwelling groups. Crews participated in a simulated planetary exploration mission that required identification, collection, and analysis of geologic samples. Results showed that crew performance effectiveness was unaffected by either positive or negative incentive conditions, while self-report measures were differentially affected—negative incentive conditions produced pronounced increases in negative self-report ratings and decreases in positive self-report ratings, while positive incentive conditions produced increased positive self-report ratings only. Thus, incentive conditions associated with simulated spaceflight missions can significantly affect psychosocial adaptation without compromising task performance effectiveness in trained and experienced crews.

  19. Effects of valerian on subjective sedation, field sobriety testing and driving simulator performance.

    Science.gov (United States)

    Thomas, Kelan; Canedo, Joanne; Perry, Paul J; Doroudgar, Shadi; Lopes, Ingrid; Chuang, Hannah Mae; Bohnert, Kimberly

    2016-07-01

    The availability of herbal medicines over-the-counter (OTC) has increased the use of natural products for self-treatment. Valerian has been used to effectively treat generalized anxiety disorder and insomnia. Studies suggest that valerenic acid may increase gamma-aminobutyric acid (GABA) modulation in the brain. Benzodiazepines have a similar mechanism of action and have been linked to an increased risk of hospitalizations due to traffic accidents. Despite the risk of somnolence, the safety of driving while under the influence of valerian remains unknown. The purpose of the study was to determine the effects of a one-time valerian 1600mg dose on subjective sedation effects, standardized field sobriety testing (SFST) and driving simulator performance parameters. The study design was a randomized, placebo-controlled, double-blind, cross-over trial. For each session, participants received either a dose of valerian or placebo. The outcome measures included a simple visual reaction test (SVRT), subjective sleepiness scales, SFST performance scores, and driving simulator performance parameters. There were no significant differences in the SVRT or sleepiness scales between placebo and valerian exposures, but the study may have been underpowered. SFST total and individual test failure rates were not significantly different between the two exposures. The driving simulator performance parameters were equivalent between the two exposure conditions. A one-time valerian 1600mg dose, often used to treat insomnia, does not appear to impair driving simulator performance after acute ingestion. Copyright © 2016 Elsevier Ltd. All rights reserved.

  20. Shoulder Arthroscopy Simulator Training Improves Shoulder Arthroscopy Performance in a Cadaver Model

    Science.gov (United States)

    Henn, R. Frank; Shah, Neel; Warner, Jon J.P.; Gomoll, Andreas H.

    2013-01-01

    Purpose The purpose of this study was to quantify the benefits of shoulder arthroscopy simulator training with a cadaver model of shoulder arthroscopy. Methods Seventeen first year medical students with no prior experience in shoulder arthroscopy were enrolled and completed this study. Each subject completed a baseline proctored arthroscopy on a cadaveric shoulder, which included controlling the camera and completing a standard series of tasks using the probe. The subjects were randomized, and nine of the subjects received training on a virtual reality simulator for shoulder arthroscopy. All subjects then repeated the same cadaveric arthroscopy. The arthroscopic videos were analyzed in a blinded fashion for time to task completion and subjective assessment of technical performance. The two groups were compared with students t-tests, and change over time within groups was analyzed with paired t-tests. Results There were no observed differences between the two groups on the baseline evaluation. The simulator group improved significantly from baseline with respect to time to completion and subjective performance (parthroscopy simulator training resulted in significant benefits in clinical shoulder arthroscopy time to task completion in this cadaver model. This study provides important additional evidence of the benefit of simulators in orthopaedic surgical training. Clinical Relevance There may be a role for simulator training in shoulder arthroscopy education. PMID:23591380

  1. Shoulder arthroscopy simulator training improves shoulder arthroscopy performance in a cadaveric model.

    Science.gov (United States)

    Henn, R Frank; Shah, Neel; Warner, Jon J P; Gomoll, Andreas H

    2013-06-01

    The purpose of this study was to quantify the benefits of shoulder arthroscopy simulator training with a cadaveric model of shoulder arthroscopy. Seventeen first-year medical students with no prior experience in shoulder arthroscopy were enrolled and completed this study. Each subject completed a baseline proctored arthroscopy on a cadaveric shoulder, which included controlling the camera and completing a standard series of tasks using the probe. The subjects were randomized, and 9 of the subjects received training on a virtual reality simulator for shoulder arthroscopy. All subjects then repeated the same cadaveric arthroscopy. The arthroscopic videos were analyzed in a blinded fashion for time to task completion and subjective assessment of technical performance. The 2 groups were compared by use of Student t tests, and change over time within groups was analyzed with paired t tests. There were no observed differences between the 2 groups on the baseline evaluation. The simulator group improved significantly from baseline with respect to time to completion and subjective performance (P arthroscopy simulator training resulted in significant benefits in clinical shoulder arthroscopy time to task completion in this cadaveric model. This study provides important additional evidence of the benefit of simulators in orthopaedic surgical training. There may be a role for simulator training in shoulder arthroscopy education. Copyright © 2013 Arthroscopy Association of North America. Published by Elsevier Inc. All rights reserved.

  2. High performance cellular level agent-based simulation with FLAME for the GPU.

    Science.gov (United States)

    Richmond, Paul; Walker, Dawn; Coakley, Simon; Romano, Daniela

    2010-05-01

    Driven by the availability of experimental data and ability to simulate a biological scale which is of immediate interest, the cellular scale is fast emerging as an ideal candidate for middle-out modelling. As with 'bottom-up' simulation approaches, cellular level simulations demand a high degree of computational power, which in large-scale simulations can only be achieved through parallel computing. The flexible large-scale agent modelling environment (FLAME) is a template driven framework for agent-based modelling (ABM) on parallel architectures ideally suited to the simulation of cellular systems. It is available for both high performance computing clusters (www.flame.ac.uk) and GPU hardware (www.flamegpu.com) and uses a formal specification technique that acts as a universal modelling format. This not only creates an abstraction from the underlying hardware architectures, but avoids the steep learning curve associated with programming them. In benchmarking tests and simulations of advanced cellular systems, FLAME GPU has reported massive improvement in performance over more traditional ABM frameworks. This allows the time spent in the development and testing stages of modelling to be drastically reduced and creates the possibility of real-time visualisation for simple visual face-validation.

  3. Comparison between the performance of some KEK-klystrons and simulation results

    Energy Technology Data Exchange (ETDEWEB)

    Fukuda, Shigeki [National Lab. for High Energy Physics, Tsukuba, Ibaraki (Japan)

    1997-04-01

    Recent developments of various klystron simulation codes have enabled us to realistically design klystrons. This paper presents various simulation results using the FCI code and the performances of tubes manufactured based on this code. Upgrading a 30-MW S-band klystron and developing a 50-MW S-band klystron for the KEKB projects are successful examples based on FCI-code predictions. Mass-productions of these tubes have already started. On the other hand, a discrepancy has been found between the FCI simulation results and the performance of real tubes. In some cases, the simulation results lead to high-efficiency results, while manufactured tubes show the usual value, or a lower value, of the efficiency. One possible cause may come from a data mismatch between the electron-gun simulation and the input data set of the FCI code for the gun region. This kind of discrepancy has been observed in 30-MW S-band pulsed tubes, sub-booster pulsed tubes and L-band high-duty pulsed klystrons. Sometimes, JPNDSK (one-dimensional disk-model code) gives similar results. Some examples using the FCI code are given in this article. An Arsenal-MSU code could be applied to the 50-MW klystron under collaboration with Moscow State University; a good agreement has been found between the prediction of the code and performance. (author)

  4. Simulation Performance and National Council Licensure Examination for Registered Nurses Outcomes: Field Research Perspectives.

    Science.gov (United States)

    Brackney, Dana E; Lane, Susan Hayes; Dawson, Tyia; Koontz, Angie

    2017-11-01

    This descriptive field study examines processes used to evaluate simulation for senior-level Bachelor of Science in Nursing (BSN) students in a capstone course, discusses challenges related to simulation evaluation, and reports the relationship between faculty evaluation of student performance and National Council Licensure Examination for Registered Nurses (NCLEX-RN) first-time passing rates. Researchers applied seven terms used to rank BSN student performance (n = 41, female, ages 22-24 years) in a senior-level capstone simulation. Faculty evaluation was correlated with students' NCLEX-RN outcomes. Students evaluated as "lacking confidence" and "flawed" were less likely to pass the NCLEX-RN on the first attempt. Faculty evaluation of capstone simulation performance provided additional evidence of student preparedness for practice in the RN role, as evidenced by the relationship between the faculty assessment and NCLEX-RN success. Simulation has been broadly accepted as a powerful educational tool that may also contribute to verification of student achievement of program outcomes and readiness for the RN role.

  5. Driving simulator performance of veterans from the Iraq and Afghanistan wars.

    Science.gov (United States)

    Amick, Melissa M; Kraft, Melissa; McGlinchey, Regina

    2013-01-01

    Driving simulator performance was examined in Operation Iraqi Freedom/Operation Enduring Freedom (OIF/OEF) Veterans to objectively evaluate driving abilities among this cohort who self-report poorer driving safety postdeployment. OIF/OEF Veterans (n = 25) and age- and education-matched civilian controls (n = 25) participated in a 30 min driving simulator assessment that measured the frequency of minor, moderate, and severe driving errors. Frequency of errors in specific content domains (speed regulation, positioning, and signaling) was also calculated. All participants answered questions about number of lifetime traffic "warnings," moving violation tickets, and accidents. Veterans completed the Posttraumatic Stress Disorder (PTSD) Checklist-Military Version. On the driving simulator assessment, Veterans committed more minor, moderate, severe, and speeding errors and reported poorer lifetime driving records than the civilian control group. Exploratory analyses revealed an association between increasing errors on the driving simulator with increasing symptoms of PTSD, although statistically this correlation did not reach significance. These findings suggest that Veterans perform more poorly on an objective evaluation of driving safety and that the presence of PTSD could be associated with worse performance on this standardized driving simulator assessment.

  6. Confidence Intervals Verification for Simulated Error Rate Performance of Wireless Communication System

    KAUST Repository

    Smadi, Mahmoud A.

    2012-12-06

    In this paper, we derived an efficient simulation method to evaluate the error rate of wireless communication system. Coherent binary phase-shift keying system is considered with imperfect channel phase recovery. The results presented demonstrate the system performance under very realistic Nakagami-m fading and additive white Gaussian noise channel. On the other hand, the accuracy of the obtained results is verified through running the simulation under a good confidence interval reliability of 95 %. We see that as the number of simulation runs N increases, the simulated error rate becomes closer to the actual one and the confidence interval difference reduces. Hence our results are expected to be of significant practical use for such scenarios. © 2012 Springer Science+Business Media New York.

  7. The Analysis and the Performance Simulation of the Capacity of Bit-interleaved Coded Modulation System

    Directory of Open Access Journals (Sweden)

    Hongwei ZHAO

    2014-09-01

    Full Text Available In this paper, the capacity of the BICM system over AWGN channels is first analyzed; the curves of BICM capacity versus SNR are also got by the Monte-Carlo simulations===?=== and compared with the curves of the CM capacity. Based on the analysis results, we simulate the error performances of BICM system with LDPC codes. Simulation results show that the capacity of BICM system with LDPC codes is enormously influenced by the mapping methods. Given a certain modulation method, the BICM system can obtain about 2-3 dB gain with Gray mapping compared with Non-Gray mapping. Meanwhile, the simulation results also demonstrate the correctness of the theory analysis.

  8. MixSim : An R Package for Simulating Data to Study Performance of Clustering Algorithms

    Directory of Open Access Journals (Sweden)

    Volodymyr Melnykov

    2012-11-01

    Full Text Available The R package MixSim is a new tool that allows simulating mixtures of Gaussian distributions with different levels of overlap between mixture components. Pairwise overlap, defined as a sum of two misclassification probabilities, measures the degree of interaction between components and can be readily employed to control the clustering complexity of datasets simulated from mixtures. These datasets can then be used for systematic performance investigation of clustering and finite mixture modeling algorithms. Among other capabilities of MixSim, there are computing the exact overlap for Gaussian mixtures, simulating Gaussian and non-Gaussian data, simulating outliers and noise variables, calculating various measures of agreement between two partitionings, and constructing parallel distribution plots for the graphical display of finite mixture models. All features of the package are illustrated in great detail. The utility of the package is highlighted through a small comparison study of several popular clustering algorithms.

  9. High performance MRI simulations of motion on multi-GPU systems.

    Science.gov (United States)

    Xanthis, Christos G; Venetis, Ioannis E; Aletras, Anthony H

    2014-07-04

    MRI physics simulators have been developed in the past for optimizing imaging protocols and for training purposes. However, these simulators have only addressed motion within a limited scope. The purpose of this study was the incorporation of realistic motion, such as cardiac motion, respiratory motion and flow, within MRI simulations in a high performance multi-GPU environment. Three different motion models were introduced in the Magnetic Resonance Imaging SIMULator (MRISIMUL) of this study: cardiac motion, respiratory motion and flow. Simulation of a simple Gradient Echo pulse sequence and a CINE pulse sequence on the corresponding anatomical model was performed. Myocardial tagging was also investigated. In pulse sequence design, software crushers were introduced to accommodate the long execution times in order to avoid spurious echoes formation. The displacement of the anatomical model isochromats was calculated within the Graphics Processing Unit (GPU) kernel for every timestep of the pulse sequence. Experiments that would allow simulation of custom anatomical and motion models were also performed. Last, simulations of motion with MRISIMUL on single-node and multi-node multi-GPU systems were examined. Gradient Echo and CINE images of the three motion models were produced and motion-related artifacts were demonstrated. The temporal evolution of the contractility of the heart was presented through the application of myocardial tagging. Better simulation performance and image quality were presented through the introduction of software crushers without the need to further increase the computational load and GPU resources. Last, MRISIMUL demonstrated an almost linear scalable performance with the increasing number of available GPU cards, in both single-node and multi-node multi-GPU computer systems. MRISIMUL is the first MR physics simulator to have implemented motion with a 3D large computational load on a single computer multi-GPU configuration. The incorporation

  10. Can we continue to ignore gender differences in performance on simulation trainers?

    Science.gov (United States)

    Thorson, Chad M; Kelly, Jason P; Forse, R Armour; Turaga, Kiran K

    2011-05-01

    There are differences between the genders in their innate performances on simulation trainers, which may impair accurate assessment of psychomotor skills. The performance of fourth-year students with no exposure to the Minimally Invasive Surgical Trainer compared based on gender, and other psychomotor skills. Our study included 16 male and 16 female students. After adjusting for choice of medical specialty (Pvideo game use (P=.6), and experience in the operating room (P=.4), female sex was an independent factor for worse performance (P=.04) in multivariate models. Women took more time than men (P<.01) and made more errors (29 versus 25 on 3 reps, P<.01). Among medical students with no previous exposure to laparoscopic trainers, female students perform worse than male students after adjusting for confounding factors. This difference must be recognized by training programs while using simulators for training and evaluation.

  11. Human System Simulation in Support of Human Performance Technical Basis at NPPs

    Energy Technology Data Exchange (ETDEWEB)

    David Gertman; Katya Le Blanc; alan mecham; william phoenix; Magdy Tawfik; Jeffrey Joe

    2010-06-01

    This paper focuses on strategies and progress toward establishing the Idaho National Laboratory’s (INL’s) Human Systems Simulator Laboratory at the Center for Advanced Energy Studies (CAES), a consortium of Idaho State Universities. The INL is one of the National Laboratories of the US Department of Energy. One of the first planned applications for the Human Systems Simulator Laboratory is implementation of a dynamic nuclear power plant simulation (NPP) where studies of operator workload, situation awareness, performance and preference will be carried out in simulated control rooms including nuclear power plant control rooms. Simulation offers a means by which to review operational concepts, improve design practices and provide a technical basis for licensing decisions. In preparation for the next generation power plant and current government and industry efforts in support of light water reactor sustainability, human operators will be attached to a suite of physiological measurement instruments and, in combination with traditional Human Factors Measurement techniques, carry out control room tasks in simulated advanced digital and hybrid analog/digital control rooms. The current focus of the Human Systems Simulator Laboratory is building core competence in quantitative and qualitative measurements of situation awareness and workload. Of particular interest is whether introduction of digital systems including automated procedures has the potential to reduce workload and enhance safety while improving situation awareness or whether workload is merely shifted and situation awareness is modified in yet to be determined ways. Data analysis is carried out by engineers and scientists and includes measures of the physical and neurological correlates of human performance. The current approach supports a user-centered design philosophy (see ISO 13407 “Human Centered Design Process for Interactive Systems, 1999) wherein the context for task performance along with the

  12. Damaris: Addressing performance variability in data management for post-petascale simulations

    International Nuclear Information System (INIS)

    Dorier, Matthieu; Antoniu, Gabriel; Cappello, Franck; Snir, Marc; Sisneros, Robert

    2016-01-01

    With exascale computing on the horizon, reducing performance variability in data management tasks (storage, visualization, analysis, etc.) is becoming a key challenge in sustaining high performance. Here, this variability significantly impacts the overall application performance at scale and its predictability over time. In this article, we present Damaris, a system that leverages dedicated cores in multicore nodes to offload data management tasks, including I/O, data compression, scheduling of data movements, in situ analysis, and visualization. We evaluate Damaris with the CM1 atmospheric simulation and the Nek5000 computational fluid dynamic simulation on four platforms, including NICS’s Kraken and NCSA’s Blue Waters. Our results show that (1) Damaris fully hides the I/O variability as well as all I/O-related costs, thus making simulation performance predictable; (2) it increases the sustained write throughput by a factor of up to 15 compared with standard I/O approaches; (3) it allows almost perfect scalability of the simulation up to over 9,000 cores, as opposed to state-of-the-art approaches that fail to scale; and (4) it enables a seamless connection to the VisIt visualization software to perform in situ analysis and visualization in a way that impacts neither the performance of the simulation nor its variability. In addition, we extended our implementation of Damaris to also support the use of dedicated nodes and conducted a thorough comparison of the two approaches—dedicated cores and dedicated nodes—for I/O tasks with the aforementioned applications.

  13. Progressive learning in endoscopy simulation training improves clinical performance: a blinded randomized trial.

    Science.gov (United States)

    Grover, Samir C; Scaffidi, Michael A; Khan, Rishad; Garg, Ankit; Al-Mazroui, Ahmed; Alomani, Tareq; Yu, Jeffrey J; Plener, Ian S; Al-Awamy, Mohamed; Yong, Elaine L; Cino, Maria; Ravindran, Nikila C; Zasowski, Mark; Grantcharov, Teodor P; Walsh, Catharine M

    2017-11-01

    A structured comprehensive curriculum (SCC) that uses simulation-based training (SBT) can improve clinical colonoscopy performance. This curriculum may be enhanced through the application of progressive learning, a training strategy centered on incrementally challenging learners. We aimed to determine whether a progressive learning-based curriculum (PLC) would lead to superior clinical performance compared with an SCC. This was a single-blinded randomized controlled trial conducted at a single academic center. Thirty-seven novice endoscopists were recruited and randomized to either a PLC (n = 18) or to an SCC (n = 19). The PLC comprised 6 hours of SBT, which progressed in complexity and difficulty. The SCC included 6 hours of SBT, with cases of random order of difficulty. Both groups received expert feedback and 4 hours of didactic teaching. Participants were assessed at baseline, immediately after training, and 4 to 6 weeks after training. The primary outcome was participants' performance during their first 2 clinical colonoscopies, as assessed by using the Joint Advisory Group Direct Observation of Procedural Skills assessment tool (JAG DOPS). Secondary outcomes were differences in endoscopic knowledge, technical and communication skills, and global performance in the simulated setting. The PLC group outperformed the SCC group during first and second clinical colonoscopies, measured by JAG DOPS (P PLC group had superior technical and communication skills and global performance in the simulated setting (P  .05). Our findings demonstrate the superiority of a PLC for endoscopic simulation, compared with an SCC. Challenging trainees progressively is a simple, theory-based approach to simulation whereby the performance of clinical colonoscopies can be improved. (Clinical trial registration number: NCT02000180.). Copyright © 2017 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  14. A novel simulation method to evaluate the collection performance of a monolithic active pixel sensor

    International Nuclear Information System (INIS)

    Fu Min; Tang Zhen'an

    2011-01-01

    A novel simulation method is presented in this paper to evaluate the collection performance of monolithic active pixel sensor (MAPS) devices for minimum ionizing particle tracking. A simplified 3D matrix pixel structure is built using the computer aided design software Sentaurus. The virtual device is then divided into hundreds of parts and an independent customized X photon model is involved in each part to simulate the conditions under 55 Fe radiation. After data processing and analysis, charge collection efficiency, collection time and diffusion conditions can be estimated in detail. In order to verify the reliability of the method, comparisons are made between the simulations and experiments. Although there are some defects, it can be concluded that the proposed idea is a feasible method for the evaluation of the MAPS collection performance. (authors)

  15. Performance Evaluation of Multithreaded Geant4 Simulations Using an Intel Xeon Phi Cluster

    Directory of Open Access Journals (Sweden)

    P. Schweitzer

    2015-01-01

    Full Text Available The objective of this study is to evaluate the performances of Intel Xeon Phi hardware accelerators for Geant4 simulations, especially for multithreaded applications. We present the complete methodology to guide users for the compilation of their Geant4 applications on Phi processors. Then, we propose series of benchmarks to compare the performance of Xeon CPUs and Phi processors for a Geant4 example dedicated to the simulation of electron dose point kernels, the TestEm12 example. First, we compare a distributed execution of a sequential version of the Geant4 example on both architectures before evaluating the multithreaded version of the Geant4 example. If Phi processors demonstrated their ability to accelerate computing time (till a factor 3.83 when distributing sequential Geant4 simulations, we do not reach the same level of speedup when considering the multithreaded version of the Geant4 example.

  16. Simulating the service life performance of an inspected group of jacket-type structures

    DEFF Research Database (Denmark)

    Schneider, Ronald; Thöns, Sebastian; Rogge, Andreas

    2017-01-01

    and risk. We intend to adopt this approach to optimize inspection, monitoring and repair activities for offshore wind park support structures. As a first step, we simulate – in analogy to an offshore wind park – the service life performance of an inspected group of jacket-type frames. The performance......A novel method for risk-based optimization of inspection and repair strategies for deteriorating structural systems has recently been proposed. The method defines heuristics at the system level to reduce the number of possible strategies. For each defined strategy, it computes the updated system...... failure probability conditional on simulated inspection and repair histories, and evaluates the associated costs and risk. The expected total service life costs and risk for a strategy are finally determined using Monte Carlo simulation. The optimal strategy minimizes the expected total service life costs...

  17. OpenMM 4: A Reusable, Extensible, Hardware Independent Library for High Performance Molecular Simulation.

    Science.gov (United States)

    Eastman, Peter; Friedrichs, Mark S; Chodera, John D; Radmer, Randall J; Bruns, Christopher M; Ku, Joy P; Beauchamp, Kyle A; Lane, Thomas J; Wang, Lee-Ping; Shukla, Diwakar; Tye, Tony; Houston, Mike; Stich, Timo; Klein, Christoph; Shirts, Michael R; Pande, Vijay S

    2013-01-08

    OpenMM is a software toolkit for performing molecular simulations on a range of high performance computing architectures. It is based on a layered architecture: the lower layers function as a reusable library that can be invoked by any application, while the upper layers form a complete environment for running molecular simulations. The library API hides all hardware-specific dependencies and optimizations from the users and developers of simulation programs: they can be run without modification on any hardware on which the API has been implemented. The current implementations of OpenMM include support for graphics processing units using the OpenCL and CUDA frameworks. In addition, OpenMM was designed to be extensible, so new hardware architectures can be accommodated and new functionality (e.g., energy terms and integrators) can be easily added.

  18. Performance evaluation of the Champagne source reconstruction algorithm on simulated and real M/EEG data.

    Science.gov (United States)

    Owen, Julia P; Wipf, David P; Attias, Hagai T; Sekihara, Kensuke; Nagarajan, Srikantan S

    2012-03-01

    In this paper, we present an extensive performance evaluation of a novel source localization algorithm, Champagne. It is derived in an empirical Bayesian framework that yields sparse solutions to the inverse problem. It is robust to correlated sources and learns the statistics of non-stimulus-evoked activity to suppress the effect of noise and interfering brain activity. We tested Champagne on both simulated and real M/EEG data. The source locations used for the simulated data were chosen to test the performance on challenging source configurations. In simulations, we found that Champagne outperforms the benchmark algorithms in terms of both the accuracy of the source localizations and the correct estimation of source time courses. We also demonstrate that Champagne is more robust to correlated brain activity present in real MEG data and is able to resolve many distinct and functionally relevant brain areas with real MEG and EEG data. Copyright © 2011 Elsevier Inc. All rights reserved.

  19. Physiological responses and performance in a simulated trampoline gymnastics competition in elite male gymnasts

    DEFF Research Database (Denmark)

    Jensen, Peter; Scott, Suzanne; Krustrup, Peter

    2013-01-01

    Abstract Physiological responses and performance were examined during and after a simulated trampoline competition (STC). Fifteen elite trampoline gymnasts participated, of which whereas eight completed two routines (EX1 and EX2) and a competition final (EX3). Trampoline-specific activities were...... gymnastic competition includes a high number of repeated explosive and energy demanding jumps, which impairs jump performance during and 24 h post-competition....

  20. Model and tool requirements for co-simulation of building performance

    NARCIS (Netherlands)

    Trcka, M.; Hensen, J.L.M.

    2006-01-01

    The use of building performance simulation (BPS) can substantially help in improving building design towards higher occupant comfort and lower fuel consumption, while reducing emission of greenhouse gasses. Unfortunately, current BPS tools do not allow inter-tool communication and thus limit a

  1. Building performance simulation as a design tool for refurbishment of buildings

    NARCIS (Netherlands)

    Hensen, J.L.M.; Bartak, M.; Drkal, F.; Dunovska, T.; Lain, M.; Matuska, T.; Schwarzer, J.; Sourek, B.; Bednar, T.

    2004-01-01

    This paper attempts to outline the current state-of-the-art regarding the use of building performance simulation as a design tool for refurbishment of buildings. This is illus-trated by means of three recent studies for conversion of historical buildings (an early 20th century factory, and a water

  2. Identifying Key Features of Student Performance in Educational Video Games and Simulations through Cluster Analysis

    Science.gov (United States)

    Kerr, Deirdre; Chung, Gregory K. W. K.

    2012-01-01

    The assessment cycle of "evidence-centered design" (ECD) provides a framework for treating an educational video game or simulation as an assessment. One of the main steps in the assessment cycle of ECD is the identification of the key features of student performance. While this process is relatively simple for multiple choice tests, when…

  3. Integration of control and building performance simulation software by run-time coupling

    NARCIS (Netherlands)

    Yahiaoui, A.; Hensen, J.L.M.; Soethout, L.L.

    2003-01-01

    This paper presents the background, approach and initial results of a project, which aims to achieve better integrated building and systems control modeling in building performance simulation by runtime coupling of distributed computer programs. This paper focuses on one of the essential steps

  4. Performance tests of the Kramers equation and boson algorithms for simulations of QCD

    International Nuclear Information System (INIS)

    Jansen, K.; Liu Chuan; Jegerlehner, B.

    1995-12-01

    We present a performance comparison of the Kramers equation and the boson algorithms for simulations of QCD with two flavors of dynamical Wilson fermions and gauge group SU(2). Results are obtained on 6 3 12, 8 3 12 and 16 4 lattices. In both algorithms a number of optimizations are installed. (orig.)

  5. Silicon drift detectors in alice experiment at lhc, performance tests and simulations

    International Nuclear Information System (INIS)

    ALICE collaboration

    2001-01-01

    A brief introduction to the silicon drift detector (SDD) in ALICE experiment at LHC CERN. Excellent agreement are found between the results from the simulation code (Ali Root) and the results of the test beam data for SDD s. A study of SDD performance and double track separation capability are shown

  6. High-performance modeling of CO2 sequestration by coupling reservoir simulation and molecular dynamics

    KAUST Repository

    Bao, Kai; Yan, Mi; Lu, Ligang; Allen, Rebecca; Salam, Amgad; Jordan, Kirk E.; Sun, Shuyu

    2013-01-01

    multicomponent compositional flow simulation to handle more complicated physical process in the future. Accuracy and scalability analysis are performed on an IBM BlueGene/P and on an IBM BlueGene/Q, the latest IBM supercomputer. Results show good accuracy of our

  7. The impact of assessing simulated bad news consultations on medical students' stress response and communication performance.

    NARCIS (Netherlands)

    Dulmen, S. van; Tromp, F.; Grosfeld, F.; Cate, O. ten; Bensing, J.M.

    2007-01-01

    Seventy second-year medical students volunteered to participate in a study with the aim of evaluating the impact of the assessment of simulated bad news consultations on their physiological and psychological stress and communication performance. Measurements were taken of salivary cortisol, systolic

  8. Numerical prediction of a bulb turbine performance hill chart through RANS simulations

    International Nuclear Information System (INIS)

    Guénette, V; Houde, S; Ciocan, G D; Deschênes, C; Dumas, G; Huang, J

    2012-01-01

    Within the framework of an international research consortium on low-head hydraulic turbine flow dynamics, the predictive behavior of Reynolds Averaged Navier-Stokes (RANS) simulations of the efficiency (η) hill chart of a bulb turbine is investigated. The paper presents the impacts of the blade tip gap and the hub gaps on performance predictions.

  9. Application of computational fluid dynamics in building performance simulation for the outdoor environment: an overview

    NARCIS (Netherlands)

    Blocken, B.J.E.; Stathopoulos, T.; Carmeliet, J.; Hensen, J.L.M.

    2011-01-01

    This paper provides an overview of the application of CFD in building performance simulation for the outdoor environment, focused on four topics: (1) pedestrian wind environment around buildings, (2) wind-driven rain on building facades, (3) convective heat transfer coefficients at exterior building

  10. 14 CFR Appendix C to Part 60 - Qualification Performance Standards for Helicopter Full Flight Simulators

    Science.gov (United States)

    2010-01-01

    ... required for aircraft certification and simulation programming and validation (b) For each maneuver or... programming and for validating the performance of the FFS, and discuss the flight test plan anticipated for..., or checking activities. r. Problems with objective test results are handled as follows: (1) If a...

  11. Simulation and analysis on thermodynamic performance of surface water source heat pump system

    Institute of Scientific and Technical Information of China (English)

    Nan Lv; Qing Zhang; Zhenqian Chen; Dongsheng Wu

    2017-01-01

    This work established a thermodynamic performance model of a heat pump system containing a heat pump unit model, an air conditioning cooling and heating load calculation model, a heat exchanger model and a water pump performance model based on mass and energy balances. The thermodynamic performance of a surface water source heat pump air conditioning system was simulated and verified by comparing the simulation results to an actual engineering project. In addition, the effects of the surface water temperature, heat exchanger structure and surface water pipeline transportation system on the thermodynamic performance of the heat pump air conditioning system were analyzed. Under the simulated conditions in this paper with a cooling load of 3400 kW, the results showed that a 1 ℃ decrease in the surface water temperature leads to a 2.3 percent increase in the coefficient of performance; furthermore, an additional 100 m of length for the closed-loop surface water heat exchanger tube leads to a 0.08 percent increase in the coefficient of performance. To decrease the system energy consumption, the optimal working point should be specified according to the surface water transportation length.

  12. Performance Evaluation of UML2-Modeled Embedded Streaming Applications with System-Level Simulation

    Directory of Open Access Journals (Sweden)

    Arpinen Tero

    2009-01-01

    Full Text Available This article presents an efficient method to capture abstract performance model of streaming data real-time embedded systems (RTESs. Unified Modeling Language version 2 (UML2 is used for the performance modeling and as a front-end for a tool framework that enables simulation-based performance evaluation and design-space exploration. The adopted application meta-model in UML resembles the Kahn Process Network (KPN model and it is targeted at simulation-based performance evaluation. The application workload modeling is done using UML2 activity diagrams, and platform is described with structural UML2 diagrams and model elements. These concepts are defined using a subset of the profile for Modeling and Analysis of Realtime and Embedded (MARTE systems from OMG and custom stereotype extensions. The goal of the performance modeling and simulation is to achieve early estimates on task response times, processing element, memory, and on-chip network utilizations, among other information that is used for design-space exploration. As a case study, a video codec application on multiple processors is modeled, evaluated, and explored. In comparison to related work, this is the first proposal that defines transformation between UML activity diagrams and streaming data application workload meta models and successfully adopts it for RTES performance evaluation.

  13. Sleep restriction during simulated wildfire suppression: effect on physical task performance.

    Science.gov (United States)

    Vincent, Grace; Ferguson, Sally A; Tran, Jacqueline; Larsen, Brianna; Wolkow, Alexander; Aisbett, Brad

    2015-01-01

    To examine the effects of sleep restriction on firefighters' physical task performance during simulated wildfire suppression. Thirty-five firefighters were matched and randomly allocated to either a control condition (8-hour sleep opportunity, n = 18) or a sleep restricted condition (4-hour sleep opportunity, n = 17). Performance on physical work tasks was evaluated across three days. In addition, heart rate, core temperature, and worker activity were measured continuously. Rate of perceived and exertion and effort sensation were evaluated during the physical work periods. There were no differences between the sleep-restricted and control groups in firefighters' task performance, heart rate, core temperature, or perceptual responses during self-paced simulated firefighting work tasks. However, the sleep-restricted group were less active during periods of non-physical work compared to the control group. Under self-paced work conditions, 4 h of sleep restriction did not adversely affect firefighters' performance on physical work tasks. However, the sleep-restricted group were less physically active throughout the simulation. This may indicate that sleep-restricted participants adapted their behaviour to conserve effort during rest periods, to subsequently ensure they were able to maintain performance during the firefighter work tasks. This work contributes new knowledge to inform fire agencies of firefighters' operational capabilities when their sleep is restricted during multi-day wildfire events. The work also highlights the need for further research to explore how sleep restriction affects physical performance during tasks of varying duration, intensity, and complexity.

  14. High-performance modeling of CO2 sequestration by coupling reservoir simulation and molecular dynamics

    KAUST Repository

    Bao, Kai

    2013-01-01

    The present work describes a parallel computational framework for CO2 sequestration simulation by coupling reservoir simulation and molecular dynamics (MD) on massively parallel HPC systems. In this framework, a parallel reservoir simulator, Reservoir Simulation Toolbox (RST), solves the flow and transport equations that describe the subsurface flow behavior, while the molecular dynamics simulations are performed to provide the required physical parameters. Numerous technologies from different fields are employed to make this novel coupled system work efficiently. One of the major applications of the framework is the modeling of large scale CO2 sequestration for long-term storage in the subsurface geological formations, such as depleted reservoirs and deep saline aquifers, which has been proposed as one of the most attractive and practical solutions to reduce the CO2 emission problem to address the global-warming threat. To effectively solve such problems, fine grids and accurate prediction of the properties of fluid mixtures are essential for accuracy. In this work, the CO2 sequestration is presented as our first example to couple the reservoir simulation and molecular dynamics, while the framework can be extended naturally to the full multiphase multicomponent compositional flow simulation to handle more complicated physical process in the future. Accuracy and scalability analysis are performed on an IBM BlueGene/P and on an IBM BlueGene/Q, the latest IBM supercomputer. Results show good accuracy of our MD simulations compared with published data, and good scalability are observed with the massively parallel HPC systems. The performance and capacity of the proposed framework are well demonstrated with several experiments with hundreds of millions to a billion cells. To our best knowledge, the work represents the first attempt to couple the reservoir simulation and molecular simulation for large scale modeling. Due to the complexity of the subsurface systems

  15. Simulation and experimental validation of the performance of a absorption refrigerator; Simulation und experimentelle Validierung des Betriebsverhaltens einer Absorptionskaeltemaschine

    Energy Technology Data Exchange (ETDEWEB)

    Olbricht, Michael; Luke, Andrea [Kassel Univ. (Germany). Fachgebiet Technische Thermodynamik

    2015-07-01

    The two biggest obstacles to a stronger market penetration of absorption refrigerators are their high cost and the size of the apparatus, which are due to the inaccurate methods for plant design. In order to contribute to an improved design a thermodynamic model is presented to describe the performance of a absorption refrigerator with the working fluid water/lithium. In this model, the processes are displayed in the single apparatus and coupled to each other in the systemic context. Thereby the interactions between the apparatus can specifically investigated and thus the process limiting component can be identified under the respective conditions. A validation of the simulation model and the boundary conditions used is done based on experimental data operating a self-developed absorption refrigerator. In the simulation, the heat transfer surfaces in accordance with the real system can be specified. The heat transport is taken into account based on typical values for the heat transfer in the individual apparatuses. Simulation results show good agreement with the experimental data. The physical relationships and influences externally defined operating parameters are correctly reproduced. Due to the chosen low heat transfer coefficient, the calculated cooling capacities by the model are below the experimentally measured. Finally, the possibilities and limitations are discussed by using the model and further improvement possibilities are suggested. [German] Die beiden groessten Hemmnisse fuer eine staerkere Marktdurchdringung von Absorptionskaeltemaschinen (AKM) sind deren hohe Anschaffungskosten sowie die Baugroesse der Apparate, die durch die ungenauen Methoden zur Anlagenauslegung begruendet sind. Als Beitrag fuer eine verbesserte Auslegung wird ein thermodynamisches Modell zur Beschreibung des Betriebsverhaltens einer AKM mit dem Arbeitsstoffpaar Wasser/Lithiumbromid vorgestellt. In diesem werden die Prozesse in den Einzelapparaten abgebildet und im systemischen

  16. Performance Assessment of Spatial Interpolation of Precipitation for Hydrological Process Simulation in the Three Gorges Basin

    Directory of Open Access Journals (Sweden)

    Meiling Cheng

    2017-11-01

    Full Text Available Accurate assessment of spatial and temporal precipitation is crucial for simulating hydrological processes in basins, but is challenging due to insufficient rain gauges. Our study aims to analyze different precipitation interpolation schemes and their performances in runoff simulation during light and heavy rain periods. In particular, combinations of different interpolation estimates are explored and their performances in runoff simulation are discussed. The study was carried out in the Pengxi River basin of the Three Gorges Basin. Precipitation data from 16 rain gauges were interpolated using the Thiessen Polygon (TP, Inverse Distance Weighted (IDW, and Co-Kriging (CK methods. Results showed that streamflow predictions employing CK inputs demonstrated the best performance in the whole process, in terms of the Nash–Sutcliffe Coefficient (NSE, the coefficient of determination (R2, and the Root Mean Square Error (RMSE indices. The TP, IDW, and CK methods showed good performance in the heavy rain period but poor performance in the light rain period compared with the default method (least sophisticated nearest neighbor technique in Soil and Water Assessment Tool (SWAT. Furthermore, the correlation between the dynamic weight of one method and its performance during runoff simulation followed a parabolic function. The combination of CK and TP achieved a better performance in decreasing the largest and lowest absolute errors compared to any single method, but the IDW method outperformed all methods in terms of the median absolute error. However, it is clear from our findings that interpolation methods should be chosen depending on the amount of precipitation, adaptability of the method, and accuracy of the estimate in different rain periods.

  17. Performance simulation of a grid connected photovoltaic power system using TRNSYS 17

    Science.gov (United States)

    Raja Sekhar, Y.; Ganesh, D.; Kumar, A. Suresh; Abraham, Raju; Padmanathan, P.

    2017-11-01

    Energy plays an important role in a country’s economic growth in the current energy scenario, the major problem is depletion of energy sources (non-renewable) are more than being formed. One of the prominent solutions is minimizing the use of fossil fuels by utilization of renewable energy resources. A photovoltaic system is an efficient option in terms of utilizing the solar energy resource. The electricity output produced by the photovoltaic systems depends upon the incident solar radiation. This paper examines the performance simulation of 200KW photovoltaic power system at VIT University, Vellore. The main objective of this paper is to correlate the results between the predicted simulation data and the experimental data. The simulation tool used here is TRNSYS. Using TRNSYS modelling prediction of electricity produced throughout the year can be calculated with the help of TRNSYS weather station. The deviation of the simulated results with the experimented results varies due to the choice of weather station. Results from the field test and simulation results are to be correlated to attain the maximum performance of the system.

  18. The effect of degree of immersion upon learning performance in virtual reality simulations for medical education.

    Science.gov (United States)

    Gutiérrez, Fátima; Pierce, Jennifer; Vergara, Víctor M; Coulter, Robert; Saland, Linda; Caudell, Thomas P; Goldsmith, Timothy E; Alverson, Dale C

    2007-01-01

    Simulations are being used in education and training to enhance understanding, improve performance, and assess competence. However, it is important to measure the performance of these simulations as learning and training tools. This study examined and compared knowledge acquisition using a knowledge structure design. The subjects were first-year medical students at The University of New Mexico School of Medicine. One group used a fully immersed virtual reality (VR) environment using a head mounted display (HMD) and another group used a partially immersed (computer screen) VR environment. The study aims were to determine whether there were significant differences between the two groups as measured by changes in knowledge structure before and after the VR simulation experience. The results showed that both groups benefited from the VR simulation training as measured by the significant increased similarity to the expert knowledge network after the training experience. However, the immersed group showed a significantly higher gain than the partially immersed group. This study demonstrated a positive effect of VR simulation on learning as reflected by improvements in knowledge structure but an enhanced effect of full-immersion using a HMD vs. a screen-based VR system.

  19. Crew Situation Awareness, Diagnoses, and Performance in Simulated Nuclear Power Plant Process Disturbances

    International Nuclear Information System (INIS)

    Sebok, Angelia; Kaarstad, Magnhild

    1998-01-01

    Research was conducted at the OECD Halden Reactor Project to identify issues in crew performance in complex simulated nuclear power plant scenarios. Eight crews of operators participated in five scenarios, administered over a two or three-day period. Scenarios required either rule-based or knowledge-based problem solving. Several performance parameters were collected, including Situation Awareness (SA), objective performance, rated crew performance, and crew diagnoses. The purpose of this study was to investigate differences in performance measures in knowledge-based and rule-based scenarios. Preliminary data analysis revealed a significant difference in crew SA between the two scenario types: crews in the rule-based scenarios had significantly higher SA then crews in the knowledge-based scenarios. Further investigations were initiated to determine if crews performed differently, in terms of objective performance, rated crew performance, and diagnoses, between the scenario types. Correlations between the various crew performance measurements were calculated to reveal insights into the nature of SA, performance, and diagnoses. The insights into crew performance can be used to design more effective interfaces and operator performance aids, thus contributing to enhanced crew performance and improved plant safety. (authors)

  20. Single and Multiple UAV Cyber-Attack Simulation and Performance Evaluation

    Directory of Open Access Journals (Sweden)

    Ahmad Y. Javaid

    2015-02-01

    Full Text Available Usage of ground, air and underwater unmanned vehicles (UGV, UAV and UUV has increased exponentially in the recent past with industries producing thousands of these unmanned vehicles every year.With the ongoing discussion of integration of UAVs in the US National Airspace, the need of a cost-effective way to verify the security and resilience of a group of communicating UAVs under attack has become very important. The answer to this need is a simulation testbed which can be used to simulate the UAV Network (UAVNet. One of these attempts is - UAVSim (Unmanned Aerial Vehicle Simulation testbed developed at the University of Toledo. It has the capability of simulating large UAV networks as well as small UAV networks with large number of attack nodes. In this paper, we analyse the performance of the simulation testbed for two attacks, targeting single and multiple UAVs. Traditional and generic computing resource available in a regular computer laboratory was used. Various evaluation results have been presented and analysed which suggest the suitability of UAVSim for UAVNet attack and swarm simulation applications.

  1. Correlations between the simulated military tasks performance and physical fitness tests at high altitude

    Directory of Open Access Journals (Sweden)

    Eduardo Borba Neves

    2017-11-01

    Full Text Available The aim of this study was to investigate the Correlations between the Simulated Military Tasks Performance and Physical Fitness Tests at high altitude. This research is part of a project to modernize the physical fitness test of the Colombian Army. Data collection was performed at the 13th Battalion of Instruction and Training, located 30km south of Bogota D.C., with a temperature range from 1ºC to 23ºC during the study period, and at 3100m above sea level. The sample was composed by 60 volunteers from three different platoons. The volunteers start the data collection protocol after 2 weeks of acclimation at this altitude. The main results were the identification of a high positive correlation between the 3 Assault wall in succession and the Simulated Military Tasks performance (r = 0.764, p<0.001, and a moderate negative correlation between pull-ups and the Simulated Military Tasks performance (r = -0.535, p<0.001. It can be recommended the use of the 20-consecutive overtaking of the 3 Assault wall in succession as a good way to estimate the performance in operational tasks which involve: assault walls, network of wires, military Climbing Nets, Tarzan jump among others, at high altitude.

  2. CFD simulation of rotor aerodynamic performance when using additional surface structure array

    Science.gov (United States)

    Wang, Bing; Kong, Deyi

    2017-10-01

    The present work analyses the aerodynamic performance of the rotor with additional surface structure array in an attempt to maximize its performance in hover flight. The unstructured grids and the Reynolds Average Navier-Stokes equations were used to calculate the performance of the prototype rotor and the rotor with additional surface structure array in the air. The computational fluid dynamics software FLUENT was used to simulate the thrust of the rotors. The results of the calculations are in reasonable agreement with experimental data, which shows that the calculation model used in this work is useful in simulating the performance of the rotor with additional surface structure array. With this theoretical calculation model, the thrusts of the rotors with arrays of surface structure in three different shapes were calculated. According to the simulation results and the experimental data, the rotor with triangle surface structure array has better aerodynamic performance than the other rotors. In contrast with the prototype rotor, the thrust of the rotor with triangle surface structure array increases by 5.2% at the operating rotating speed of 3000r/min, and the additional triangle surface structure array has almost no influence on the efficiency of the rotor.

  3. Simulating Study on Drive System Performance for Hybrid Electric Bus Based on ADVISOR

    Directory of Open Access Journals (Sweden)

    Wang Xingxing

    2017-01-01

    Full Text Available Hybrid electric bus has a number of advantages when compared with ordinary passenger cars, but in the dynamic matching and the vehicle performance are difficult to detect, thus limits its development process. In this paper, combined with the actual models, the hybrid electric bus module parameters were modified in the software of ADVISOR (Advanced Vehicle Simulator, main including: module of the vehicle, the wheel module, motor module, a battery module and engine module, three kinds of bus models for A, B and C were established, and the related performance that need to be analyzed was set up, such as acceleration, gradability, emissions and energy utilization and so on, in order to ensure the vehicle running in the same environment and convenient for comparison, a fixed vehicle driving cycles was chose, then the simulation results was analyzed, and the various performance was compared with the dynamic indicators and economic indicators which determined by referencing of traditional city bus standard and each other, and finally, the performance optimal model of B was chose out which can meet the demand, its related performance parameters of the simulation results are as follows: the best gradability is 26%, maximum speed is 72.7km/h, maximum acceleration is 1.7m/s2, 0~50km/h acceleration time is 9.5s and fuel consumption is 25L/km.

  4. An empirical investigation of operator performance in cognitively demanding simulated emergencies

    International Nuclear Information System (INIS)

    Roth, E.M.; Mumaw, R.J.; Lewis, P.M.

    1994-07-01

    This report documents the results of an empirical study of nuclear power plant operator performance in cognitively demanding simulated emergencies. During emergencies operators follow highly prescriptive written procedures. The objectives of the study were to understand and document what role higher-level cognitive activities such as diagnosis, or more generally 'situation assessment', play in guiding operator performance, given that operators utilize procedures in responding to the events. The study examined crew performance in variants of two emergencies: (1) an Interfacing System Loss of Coolant Accident and (2) a Loss of Heat Sink scenario. Data on operator performance were collected using training simulators at two plant sites. Up to 11 crews from each plant participated in each of two simulated emergencies for a total of 38 cases. Crew performance was videotaped and partial transcripts were produced and analyzed. The results revealed a number of instances where higher-level cognitive activities such as situation assessment and response planning enabled crews to handle aspects of the situation that were not fully addressed by the procedures. This report documents these cases and discusses their implications for the development and evaluation of training and control room aids, as well as for human reliability analyses

  5. Design of thermoelectric modules for both mechanical reliability and performance using FE simulation

    DEFF Research Database (Denmark)

    Sarhadi, Ali; Bjørk, Rasmus; Pryds, Nini

    for these two objectives. The current study deals with FE simulation of the TE modules to optimize their geometrical dimension in terms of mechanical reliability and performance. First, FE simulation of a TE module consisting of bismuth telluride alloys is carried out and the induced thermal stresses, output......, the geometrical dimensions of the TE elements for both mechanical reliability and performance are optimized to obtain a compromise design. The present work provides a basis for optimizing the TE modules in terms of their life time and performance.......Thermo-mechanical modeling of the TE modules provides an efficient tool for assessing the mechanical strength of the modules against the induced thermal stresses and subsequently optimizing them in terms of the mechanical reliability. However, the design of TE modules in terms of mechanical...

  6. Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC).

    Energy Technology Data Exchange (ETDEWEB)

    Schultz, Peter Andrew

    2011-12-01

    The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M&S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. Achieving the objective of modeling the performance of a disposal scenario requires describing processes involved in waste form degradation and radionuclide release at the subcontinuum scale, beginning with mechanistic descriptions of chemical reactions and chemical kinetics at the atomic scale, and upscaling into effective, validated constitutive models for input to high-fidelity continuum scale codes for coupled multiphysics simulations of release and transport. Verification and validation (V&V) is required throughout the system to establish evidence-based metrics for the level of confidence in M&S codes and capabilities, including at the subcontiunuum scale and the constitutive models they inform or generate. This Report outlines the nature of the V&V challenge at the subcontinuum scale, an approach to incorporate V&V concepts into subcontinuum scale modeling and simulation (M&S), and a plan to incrementally incorporate effective V&V into subcontinuum scale M&S destined for use in the NEAMS Waste IPSC work flow to meet requirements of quantitative confidence in the constitutive models informed by subcontinuum scale phenomena.

  7. Results from Tight and Loose Coupled Multiphysics in Nuclear Fuels Performance Simulations using BISON

    Energy Technology Data Exchange (ETDEWEB)

    S. R. Novascone; B. W. Spencer; D. Andrs; R. L. Williamson; J. D. Hales; D. M. Perez

    2013-05-01

    The behavior of nuclear fuel in the reactor environment is affected by multiple physics, most notably heat conduction and solid mechanics, which can have a strong influence on each other. To provide credible solutions, a fuel performance simulation code must have the ability to obtain solutions for each of the physics, including coupling between them. Solution strategies for solving systems of coupled equations can be categorized as loosely-coupled, where the individual physics are solved separately, keeping the solutions for the other physics fixed at each iteration, or tightly coupled, where the nonlinear solver simultaneously drives down the residual for each physics, taking into account the coupling between the physics in each nonlinear iteration. In this paper, we compare the performance of loosely and tightly coupled solution algorithms for thermomechanical problems involving coupled thermal and mechanical contact, which is a primary source of interdependence between thermal and mechanical solutions in fuel performance models. The results indicate that loosely-coupled simulations require significantly more nonlinear iterations, and may lead to convergence trouble when the thermal conductivity of the gap is too small. We also apply the tightly coupled solution strategy to a nuclear fuel simulation of an experiment in a test reactor. Studying the results from these simulations indicates that perhaps convergence for either approach may be problem dependent, i.e., there may be problems for which a loose coupled approach converges, where tightly coupled won’t converge and vice versa.

  8. Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC)

    International Nuclear Information System (INIS)

    Schultz, Peter Andrew

    2011-01-01

    The objective of the U.S. Department of Energy Office of Nuclear Energy Advanced Modeling and Simulation Waste Integrated Performance and Safety Codes (NEAMS Waste IPSC) is to provide an integrated suite of computational modeling and simulation (M and S) capabilities to quantitatively assess the long-term performance of waste forms in the engineered and geologic environments of a radioactive-waste storage facility or disposal repository. Achieving the objective of modeling the performance of a disposal scenario requires describing processes involved in waste form degradation and radionuclide release at the subcontinuum scale, beginning with mechanistic descriptions of chemical reactions and chemical kinetics at the atomic scale, and upscaling into effective, validated constitutive models for input to high-fidelity continuum scale codes for coupled multiphysics simulations of release and transport. Verification and validation (V and V) is required throughout the system to establish evidence-based metrics for the level of confidence in M and S codes and capabilities, including at the subcontiunuum scale and the constitutive models they inform or generate. This Report outlines the nature of the V and V challenge at the subcontinuum scale, an approach to incorporate V and V concepts into subcontinuum scale modeling and simulation (M and S), and a plan to incrementally incorporate effective V and V into subcontinuum scale M and S destined for use in the NEAMS Waste IPSC work flow to meet requirements of quantitative confidence in the constitutive models informed by subcontinuum scale phenomena.

  9. Results from tight and loose coupled multiphysics in nuclear fuels performance simulations using BISON

    International Nuclear Information System (INIS)

    Novascone, S. R.; Spencer, B. W.; Andrs, D.; Williamson, R. L.; Hales, J. D.; Perez, D. M.

    2013-01-01

    The behavior of nuclear fuel in the reactor environment is affected by multiple physics, most notably heat conduction and solid mechanics, which can have a strong influence on each other. To provide credible solutions, a fuel performance simulation code must have the ability to obtain solutions for each of the physics, including coupling between them. Solution strategies for solving systems of coupled equations can be categorized as loosely-coupled, where the individual physics are solved separately, keeping the solutions for the other physics fixed at each iteration, or tightly coupled, where the nonlinear solver simultaneously drives down the residual for each physics, taking into account the coupling between the physics in each nonlinear iteration. In this paper, we compare the performance of loosely and tightly coupled solution algorithms for thermomechanical problems involving coupled thermal and mechanical contact, which is a primary source of interdependence between thermal and mechanical solutions in fuel performance models. The results indicate that loosely-coupled simulations require significantly more nonlinear iterations, and may lead to convergence trouble when the thermal conductivity of the gap is too small. We also apply the tightly coupled solution strategy to a nuclear fuel simulation of an experiment in a test reactor. Studying the results from these simulations indicates that perhaps convergence for either approach may be problem dependent, i.e., there may be problems for which a loose coupled approach converges, where tightly coupled won't converge and vice versa. (authors)

  10. Novel types of surface acoustic wave microreflectors - Performance analysis and simulations

    Science.gov (United States)

    Golan, G.; Griffel, G.; Seidman, A.; Croitoru, N.

    1990-06-01

    Surface acoustic waves for micrograting reflectors have been characterized. Based on the perturbation theory, eight different types of structures on an acoustic waveguide were analyzed. Results of simulations of all eight types of corrugation structures were evaluated in order to find the least leaky waveguide, the most efficient reflector (with minimum necessary perturbations), and the optimal mode shape for improved performances. General design curves are presented in order to illustrate the behavior of the incident and reflected waves under a variety of structural conditions. Analytic expressions for the calculations of the mode amplitude and mode shape, and for general acoustic corrugations are derived and then the simulations results are presented.

  11. Design of GNSS Performance Analysis and Simulation Tools as a Web Portal

    Directory of Open Access Journals (Sweden)

    S. Tadic

    2014-11-01

    Full Text Available This paper considers design of a web-portal for the validation of behavior of GNSS applications in different environments. The tool provides the positioning performance analysis and a comparison to benchmark devices. Web-portal incorporates a 3D synthetic data generator to compute the propagation and the reception of radio-navigation signals in a 3D virtual environment. This radio propagation simulator uses ray-tracing to calculate interactions between the GNSS signal and the local environment. For faster execution on a GPU platform, the simulator uses BVH optimization. The work is verified in field trials and by using reference software.

  12. Sustained effect of simulation-based ultrasound training on clinical performance: a randomized trial

    Science.gov (United States)

    Tolsgaard, M G; Ringsted, C; Dreisler, E; Nørgaard, L N; Petersen, J H; Madsen, M E; Freiesleben, N L C; Sørensen, J L; Tabor, A

    2015-01-01

    Objective To study the effect of initial simulation-based transvaginal sonography (TVS) training compared with clinical training only, on the clinical performance of residents in obstetrics and gynecology (Ob-Gyn), assessed 2 months into their residency. Methods In a randomized study, new Ob-Gyn residents (n = 33) with no prior ultrasound experience were recruited from three teaching hospitals. Participants were allocated to either simulation-based training followed by clinical training (intervention group; n = 18) or clinical training only (control group; n = 15). The simulation-based training was performed using a virtual-reality TVS simulator until an expert performance level was attained, and was followed by training on a pelvic mannequin. After 2 months of clinical training, one TVS examination was recorded for assessment of each resident's clinical performance (n = 26). Two ultrasound experts blinded to group allocation rated the scans using the Objective Structured Assessment of Ultrasound Skills (OSAUS) scale. Results During the 2 months of clinical training, participants in the intervention and control groups completed an average ± SD of 58 ± 41 and 63 ± 47 scans, respectively (P = 0.67). In the subsequent clinical performance test, the intervention group achieved higher OSAUS scores than did the control group (mean score, 59.1% vs 37.6%, respectively; P training leads to substantial improvement in clinical performance that is sustained after 2 months of clinical training. © 2015 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of the International Society of Ultrasound in Obstetrics and Gynecology. PMID:25580809

  13. Thermodynamic simulation model for predicting the performance of spark ignition engines using biogas as fuel

    International Nuclear Information System (INIS)

    Nunes de Faria, Mário M.; Vargas Machuca Bueno, Juan P.; Ayad, Sami M.M. Elmassalami; Belchior, Carlos R. Pereira

    2017-01-01

    Highlights: • A 0-D model for performance prediction of SI ICE fueled with biogas is proposed. • Relative difference between simulated and experimental values was under 5%. • Can be adapted for different biogas compositions and operating ranges. • Could be a valuable tool for predicting trends and guiding experimentation. • Is suitable for use with biogas supplies in developing regions. - Abstract: Biogas found its way from developing countries and is now an alternative to fossil fuels in internal combustion engines and with the advantage of lower greenhouse gas emissions. However, its use in gas engines requires engine modifications or adaptations that may be costly. This paper reports the results of experimental performance and emissions tests of an engine-generator unit fueled with biogas produced in a sewage plant in Brazil, operating under different loads, and with suitable engine modifications. These emissions and performance results were in agreement with the literature and it was confirmed that the penalties to engine performance were more significant than emission reduction in the operating range tested. Furthermore, a zero dimensional simulation model was employed to predict performance characteristics. Moreover, a differential thermodynamic equation system was solved, obtaining the pressure inside the cylinder as a function of the crank angle for different engine conditions. Mean effective pressure and indicated power were also obtained. The results of simulation and experimental tests of the engine in similar conditions were compared and the model validated. Although several simplifying assumptions were adopted and empirical correlations were used for Wiebe function, the model was adequate in predicting engine performance as the relative difference between simulated and experimental values was lower than 5%. The model can be adapted for use with different raw or enriched biogas compositions and could prove to be a valuable tool to guide

  14. Identification of New Tools to Predict Surgical Performance of Novices using a Plastic Surgery Simulator.

    Science.gov (United States)

    Kazan, Roy; Viezel-Mathieu, Alex; Cyr, Shantale; Hemmerling, Thomas M; Lin, Samuel J; Gilardino, Mirko S

    2018-04-09

    To identify new tools capable of predicting surgical performance of novices on an augmentation mammoplasty simulator. The pace of technical skills acquisition varies between residents and may necessitate more time than that allotted by residency training before reaching competence. Identifying applicants with superior innate technical abilities might shorten learning curves and the time to reach competence. The objective of this study is to identify new tools that could predict surgical performance of novices on a mammoplasty simulator. We recruited 14 medical students and recorded their performance in 2 skill-games: Mikado and Perplexus Epic, and in 2 video games: Star War Racer (Sony Playstation 3) and Super Monkey Ball 2 (Nintendo Wii). Then, each participant performed an augmentation mammoplasty procedure on a Mammoplasty Part-task Trainer, which allows the simulation of the essential steps of the procedure. The average age of participants was 25.4 years. Correlation studies showed significant association between Perplexus Epic, Star Wars Racer, Super Monkey Ball scores and the modified OSATS score with r s = 0.8491 (p 41 (p = 0.005), and r s = 0.7309 (p < 0.003), but not with the Mikado score r s = -0.0255 (p = 0.9). Linear regressions were strongest for Perplexus Epic and Super Monkey Ball scores with coefficients of determination of 0.59 and 0.55, respectively. A combined score (Perplexus/Super-Monkey-Ball) was computed and showed a significant correlation with the modified OSATS score having an r s = 0.8107 (p < 0.001) and R 2 = 0.75, respectively. This study identified a combination of skill games that correlated to better performance of novices on a surgical simulator. With refinement, such tools could serve to help screen plastic surgery applicants and identify those with higher surgical performance predictors. Copyright © 2018 Association of Program Directors in Surgery. Published by Elsevier Inc. All rights reserved.

  15. Psychophysiological Assessment in Pilots Performing Challenging Simulated and Real Flight Maneuvers.

    Science.gov (United States)

    Johannes, Bernd; Rothe, Stefanie; Gens, André; Westphal, Soeren; Birkenfeld, Katja; Mulder, Edwin; Rittweger, Jörn; Ledderhos, Carla

    2017-09-01

    The objective assessment of psychophysiological arousal during challenging flight maneuvers is of great interest to aerospace medicine, but remains a challenging task. In the study presented here, a vector-methodological approach was used which integrates different psychophysiological variables, yielding an integral arousal index called the Psychophysiological Arousal Value (PAV). The arousal levels of 15 male pilots were assessed during predetermined, well-defined flight maneuvers performed under simulated and real flight conditions. The physiological data, as expected, revealed inter- and intra-individual differences for the various measurement conditions. As indicated by the PAV, air-to-air refueling (AAR) turned out to be the most challenging task. In general, arousal levels were comparable between simulator and real flight conditions. However, a distinct difference was observed when the pilots were divided by instructors into two groups based on their proficiency in AAR with AWACS (AAR-Novices vs. AAR-Professionals). AAR-Novices had on average more than 2000 flight hours on other aircrafts. They showed higher arousal reactions to AAR in real flight (contact: PAV score 8.4 ± 0.37) than under simulator conditions (7.1 ± 0.30), whereas AAR-Professionals did not (8.5 ± 0.46 vs. 8.8 ± 0.80). The psychophysiological arousal value assessment was tested in field measurements, yielding quantifiable arousal differences between proficiency groups of pilots during simulated and real flight conditions. The method used in this study allows an evaluation of the psychophysiological cost during a certain flying performance and thus is possibly a valuable tool for objectively evaluating the actual skill status of pilots.Johannes B, Rothe S, Gens A, Westphal S, Birkenfeld K, Mulder E, Rittweger J, Ledderhos C. Psychophysiological assessment in pilots performing challenging simulated and real flight maneuvers. Aerosp Med Hum Perform. 2017; 88(9):834-840.

  16. Evaluation of upper body muscle activity during cardiopulmonary resuscitation performance in simulated microgravity

    Science.gov (United States)

    Waye, A. B.; Krygiel, R. G.; Susin, T. B.; Baptista, R.; Rehnberg, L.; Heidner, G. S.; de Campos, F.; Falcão, F. P.; Russomano, T.

    2013-09-01

    Performance of efficient single-person cardiopulmonary resuscitation (CPR) is vital to maintain cardiac and cerebral perfusion during the 2-4 min it takes for deployment of advanced life support during a space mission. The aim of the present study was to investigate potential differences in upper body muscle activity during CPR performance at terrestrial gravity (+1Gz) and in simulated microgravity (μG). Muscle activity of the triceps brachii, erector spinae, rectus abdominis and pectoralis major was measured via superficial electromyography in 20 healthy male volunteers. Four sets of 30 external chest compressions (ECCs) were performed on a mannequin. Microgravity was simulated using a body suspension device and harness; the Evetts-Russomano (ER) method was adopted for CPR performance in simulated microgravity. Heart rate and perceived exertion via Borg scores were also measured. While a significantly lower depth of ECCs was observed in simulated microgravity, compared with +1Gz, it was still within the target range of 40-50 mm. There was a 7.7% decrease of the mean (±SEM) ECC depth from 48 ± 0.3 mm at +1Gz, to 44.3 ± 0.5 mm during microgravity simulation (p < 0.001). No significant difference in number or rate of compressions was found between the two conditions. Heart rate displayed a significantly larger increase during CPR in simulated microgravity than at +1Gz, the former presenting a mean (±SEM) of 23.6 ± 2.91 bpm and the latter, 76.6 ± 3.8 bpm (p < 0.001). Borg scores were 70% higher post-microgravity compressions (17 ± 1) than post +1Gz compressions (10 ± 1) (p < 0.001). Intermuscular comparisons showed the triceps brachii to have significantly lower muscle activity than each of the other three tested muscles, in both +1Gz and microgravity. As shown by greater Borg scores and heart rate increases, CPR performance in simulated microgravity is more fatiguing than at +1Gz. Nevertheless, no significant difference in muscle activity between conditions

  17. Validation of the updated ArthroS simulator: face and construct validity of a passive haptic virtual reality simulator with novel performance metrics.

    Science.gov (United States)

    Garfjeld Roberts, Patrick; Guyver, Paul; Baldwin, Mathew; Akhtar, Kash; Alvand, Abtin; Price, Andrew J; Rees, Jonathan L

    2017-02-01

    To assess the construct and face validity of ArthroS, a passive haptic VR simulator. A secondary aim was to evaluate the novel performance metrics produced by this simulator. Two groups of 30 participants, each divided into novice, intermediate or expert based on arthroscopic experience, completed three separate tasks on either the knee or shoulder module of the simulator. Performance was recorded using 12 automatically generated performance metrics and video footage of the arthroscopic procedures. The videos were blindly assessed using a validated global rating scale (GRS). Participants completed a survey about the simulator's realism and training utility. This new simulator demonstrated construct validity of its tasks when evaluated against a GRS (p ≤ 0.003 in all cases). Regarding it's automatically generated performance metrics, established outputs such as time taken (p ≤ 0.001) and instrument path length (p ≤ 0.007) also demonstrated good construct validity. However, two-thirds of the proposed 'novel metrics' the simulator reports could not distinguish participants based on arthroscopic experience. Face validity assessment rated the simulator as a realistic and useful tool for trainees, but the passive haptic feedback (a key feature of this simulator) is rated as less realistic. The ArthroS simulator has good task construct validity based on established objective outputs, but some of the novel performance metrics could not distinguish between surgical experience. The passive haptic feedback of the simulator also needs improvement. If simulators could offer automated and validated performance feedback, this would facilitate improvements in the delivery of training by allowing trainees to practise and self-assess.

  18. High Performance Wideband CMOS CCI and its Application in Inductance Simulator Design

    Directory of Open Access Journals (Sweden)

    ARSLAN, E.

    2012-08-01

    Full Text Available In this paper, a new, differential pair based, low-voltage, high performance and wideband CMOS first generation current conveyor (CCI is proposed. The proposed CCI has high voltage swings on ports X and Y and very low equivalent impedance on port X due to super source follower configuration. It also has high voltage swings (close to supply voltages on input and output ports and wideband current and voltage transfer ratios. Furthermore, two novel grounded inductance simulator circuits are proposed as application examples. Using HSpice, it is shown that the simulation results of the proposed CCI and also of the presented inductance simulators are in very good agreement with the expected ones.

  19. Simulation on the Performance of Dye Solar Cell Incorporated with TiO2 Passivation Layer

    Directory of Open Access Journals (Sweden)

    Unan Yusmaniar Oktiawati

    2016-01-01

    Full Text Available Dye Solar Cell (DSC has started to gain interest in the recent years for practical application because of its ecofriendly, low cost, and easy fabrication. However, its efficiency is still not as competitive as the conventional silicon based solar cell. One of the research efforts to improve the efficiency of DSC is to use the passivation layer in between the photoelectrode material and the conductive oxide substrate. Thus, the objective of this simulation study is to investigate the effect of passivation layer on the performance of DSC. Properties from literatures which are based on physical work were captured as the input for the simulation using process, ATHENA, and device, ATLAS, simulator. Results have shown that the addition of two-20 nm TiO2 passivation layers on DSC can enhance the efficiency by 11% as the result of less recombination, higher electron mobility, and longer electron lifetime.

  20. Performance optimization and validation of ADM1 simulations under anaerobic thermophilic conditions

    KAUST Repository

    Atallah, Nabil M.

    2014-12-01

    In this study, two experimental sets of data each involving two thermophilic anaerobic digesters treating food waste, were simulated using the Anaerobic Digestion Model No. 1 (ADM1). A sensitivity analysis was conducted, using both data sets of one digester, for parameter optimization based on five measured performance indicators: methane generation, pH, acetate, total COD, ammonia, and an equally weighted combination of the five indicators. The simulation results revealed that while optimization with respect to methane alone, a commonly adopted approach, succeeded in simulating methane experimental results, it predicted other intermediary outputs less accurately. On the other hand, the multi-objective optimization has the advantage of providing better results than methane optimization despite not capturing the intermediary output. The results from the parameter optimization were validated upon their independent application on the data sets of the second digester.

  1. Investigating the Mobility of Light Autonomous Tracked Vehicles using a High Performance Computing Simulation Capability

    Science.gov (United States)

    Negrut, Dan; Mazhar, Hammad; Melanz, Daniel; Lamb, David; Jayakumar, Paramsothy; Letherwood, Michael; Jain, Abhinandan; Quadrelli, Marco

    2012-01-01

    This paper is concerned with the physics-based simulation of light tracked vehicles operating on rough deformable terrain. The focus is on small autonomous vehicles, which weigh less than 100 lb and move on deformable and rough terrain that is feature rich and no longer representable using a continuum approach. A scenario of interest is, for instance, the simulation of a reconnaissance mission for a high mobility lightweight robot where objects such as a boulder or a ditch that could otherwise be considered small for a truck or tank, become major obstacles that can impede the mobility of the light autonomous vehicle and negatively impact the success of its mission. Analyzing and gauging the mobility and performance of these light vehicles is accomplished through a modeling and simulation capability called Chrono::Engine. Chrono::Engine relies on parallel execution on Graphics Processing Unit (GPU) cards.

  2. Cognitive test performance following exposure to noise in an open-office simulation study

    DEFF Research Database (Denmark)

    Lund, Søren Peter; Kristiansen, Jesper; Persson, Roger

    each simulated workday, the participants performed different tests, including Choice Reaction Time (CRT) test, Sustained Attention to Response Task (SART) test, and a Two-Back Task (TBT) test. Results: Working in noise did not affect the number of correct trials in the cognitive test after work. Yet......Objective: Noise in open-plan offices may increase mental fatigue of the employees at the end of the day. Measurements: 225 employees completed a screening questionnaire. Of these, 50 persons (33 females) who normally worked in open-plan offices agreed to participate in the experiment. All who...... participated completed two counter balanced experimental sessions, one with exposure to simulation of office noise (Leq=55 dB(A)) and one without noise (Leq=50 dB(A)). To simulate a workday, each session lasted about 7 hours, where the participants engaged in different computerised work tasks. Before and after...

  3. Performance optimization and validation of ADM1 simulations under anaerobic thermophilic conditions.

    Science.gov (United States)

    Atallah, Nabil M; El-Fadel, Mutasem; Ghanimeh, Sophia; Saikaly, Pascal; Abou-Najm, Majdi

    2014-12-01

    In this study, two experimental sets of data each involving two thermophilic anaerobic digesters treating food waste, were simulated using the Anaerobic Digestion Model No. 1 (ADM1). A sensitivity analysis was conducted, using both data sets of one digester, for parameter optimization based on five measured performance indicators: methane generation, pH, acetate, total COD, ammonia, and an equally weighted combination of the five indicators. The simulation results revealed that while optimization with respect to methane alone, a commonly adopted approach, succeeded in simulating methane experimental results, it predicted other intermediary outputs less accurately. On the other hand, the multi-objective optimization has the advantage of providing better results than methane optimization despite not capturing the intermediary output. The results from the parameter optimization were validated upon their independent application on the data sets of the second digester. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Performance optimization and validation of ADM1 simulations under anaerobic thermophilic conditions

    KAUST Repository

    Atallah, Nabil M.; El-Fadel, Mutasem E.; Ghanimeh, Sophia A.; Saikaly, Pascal; Abou Najm, Majdi R.

    2014-01-01

    In this study, two experimental sets of data each involving two thermophilic anaerobic digesters treating food waste, were simulated using the Anaerobic Digestion Model No. 1 (ADM1). A sensitivity analysis was conducted, using both data sets of one digester, for parameter optimization based on five measured performance indicators: methane generation, pH, acetate, total COD, ammonia, and an equally weighted combination of the five indicators. The simulation results revealed that while optimization with respect to methane alone, a commonly adopted approach, succeeded in simulating methane experimental results, it predicted other intermediary outputs less accurately. On the other hand, the multi-objective optimization has the advantage of providing better results than methane optimization despite not capturing the intermediary output. The results from the parameter optimization were validated upon their independent application on the data sets of the second digester.

  5. Comparison of Numerically Simulated and Experimentally Measured Performance of a Rotating Detonation Engine

    Science.gov (United States)

    Paxson, Daniel E.; Fotia, Matthew L.; Hoke, John; Schauer, Fred

    2015-01-01

    A quasi-two-dimensional, computational fluid dynamic (CFD) simulation of a rotating detonation engine (RDE) is described. The simulation operates in the detonation frame of reference and utilizes a relatively coarse grid such that only the essential primary flow field structure is captured. This construction and other simplifications yield rapidly converging, steady solutions. Viscous effects, and heat transfer effects are modeled using source terms. The effects of potential inlet flow reversals are modeled using boundary conditions. Results from the simulation are compared to measured data from an experimental RDE rig with a converging-diverging nozzle added. The comparison is favorable for the two operating points examined. The utility of the code as a performance optimization tool and a diagnostic tool are discussed.

  6. Visuospatial and psychomotor aptitude predicts endovascular performance of inexperienced individuals on a virtual reality simulator.

    Science.gov (United States)

    Van Herzeele, Isabelle; O'Donoghue, Kevin G L; Aggarwal, Rajesh; Vermassen, Frank; Darzi, Ara; Cheshire, Nicholas J W

    2010-04-01

    This study evaluated virtual reality (VR) simulation for endovascular training of medical students to determine whether innate perceptual, visuospatial, and psychomotor aptitude (VSA) can predict initial and plateau phase of technical endovascular skills acquisition. Twenty medical students received didactic and endovascular training on a commercially available VR simulator. Each student treated a series of 10 identical noncomplex renal artery stenoses endovascularly. The simulator recorded performance data instantly and objectively. An experienced interventionalist rated the performance at the initial and final sessions using generic (out of 40) and procedure-specific (out of 30) rating scales. VSA were tested with fine motor dexterity (FMD, Perdue Pegboard), psychomotor ability (minimally invasive virtual reality surgical trainer [MIST-VR]), image recall (Rey-Osterrieth), and organizational aptitude (map-planning). VSA performance scores were correlated with the assessment parameters of endovascular skills at commencement and completion of training. Medical students exhibited statistically significant learning curves from the initial to the plateau performance for contrast usage (medians, 28 vs 17 mL, P dexterity as well as with image recall at end of the training period. In addition to current recruitment strategies, VSA may be a useful tool for predictive validity studies.

  7. The impact of meal timing on performance, sleepiness, gastric upset, and hunger during simulated night shift.

    Science.gov (United States)

    Grant, Crystal Leigh; Dorrian, Jillian; Coates, Alison Maree; Pajcin, Maja; Kennaway, David John; Wittert, Gary Allen; Heilbronn, Leonie Kaye; Vedova, Chris Della; Gupta, Charlotte Cecilia; Banks, Siobhan

    2017-10-07

    This study examined the impact of eating during simulated night shift on performance and subjective complaints. Subjects were randomized to eating at night (n=5; 23.2 ± 5.5 y) or not eating at night (n=5; 26.2 ± 6.4 y). All participants were given one sleep opportunity of 8 h (22:00 h-06:00 h) before transitioning to the night shift protocol. During the four days of simulated night shift participants were awake from 16:00 h-10:00 h with a daytime sleep of 6 h (10:00 h-16:00 h). In the simulated night shift protocol, meals were provided at ≈0700 h, 1900 h and 0130 h (eating at night); or ≈0700 h, 0930 h, 1410 h and 1900 h (not eating at night). Subjects completed sleepiness, hunger and gastric complaint scales, a Digit Symbol Substitution Task and a 10-min Psychomotor Vigilance Task. Increased sleepiness and performance impairment was evident in both conditions at 0400 h (phunger and a small but significant elevation in stomach upset across the night (p<0.026). Eating at night was associated with elevated bloating on night one, which decreased across the protocol. Restricting food intake may limit performance impairments at night. Dietary recommendations to improve night-shift performance must also consider worker comfort.

  8. High-resolution 3D simulations of NIF ignition targets performed on Sequoia with HYDRA

    Science.gov (United States)

    Marinak, M. M.; Clark, D. S.; Jones, O. S.; Kerbel, G. D.; Sepke, S.; Patel, M. V.; Koning, J. M.; Schroeder, C. R.

    2015-11-01

    Developments in the multiphysics ICF code HYDRA enable it to perform large-scale simulations on the Sequoia machine at LLNL. With an aggregate computing power of 20 Petaflops, Sequoia offers an unprecedented capability to resolve the physical processes in NIF ignition targets for a more complete, consistent treatment of the sources of asymmetry. We describe modifications to HYDRA that enable it to scale to over one million processes on Sequoia. These include new options for replicating parts of the mesh over a subset of the processes, to avoid strong scaling limits. We consider results from a 3D full ignition capsule-only simulation performed using over one billion zones run on 262,000 processors which resolves surface perturbations through modes l = 200. We also report progress towards a high-resolution 3D integrated hohlraum simulation performed using 262,000 processors which resolves surface perturbations on the ignition capsule through modes l = 70. These aim for the most complete calculations yet of the interactions and overall impact of the various sources of asymmetry for NIF ignition targets. This work was performed under the auspices of the Lawrence Livermore National Security, LLC, (LLNS) under Contract No. DE-AC52-07NA27344.

  9. Analysis of performance and stress caused by a simulation of a mass casualty incident.

    Science.gov (United States)

    Nieto Fernández-Pacheco, Antonio; Castro Delgado, Rafael; Arcos González, Pedro; Navarro Fernández, José Luis; Cerón Madrigal, José Joaquín; Juguera Rodriguez, Laura; Perez Alonso, Nuria; Armero-Barranco, David; Lidon López Iborra, María; Damian, Escribano Tortosa; Pardo Rios, Manuel

    2018-03-01

    To determine the stress that is potentially produced in professional health workers due to a mass casualty incident (MCI) simulated exercise, and its relation to prior academic training and the role played in the simulation. Observational study of stress in a MCI. For this work, two MCI drills comprised of 40 victims each were conducted. Two randomized groups of 36 students each were created: Master's Students Group (MSG) and Undergraduate Student Group (USG). The role performed by each student (triage or sectorization) was assessed. The stress level was determined by prior and subsequent measurements of alpha-amylase (αA), HR, SBP and DBP. The percentage of victims that were correctly triaged was 88.6%, 91.84% for MSG and 83.76% for the USG (p=0.004). The basal αA was 97,107.50±72,182.67IU/L and the subsequent αA was 136,195.55±90,176.46±IU/L (pperformed the triage and those who performed sectorization but there were no differences between undergraduate and Masters' students. Conducting a simulated exercise caused stress in personnel involved in the MCI, with a greater impact on participants who performed triage, although it was not influenced by their prior academic level. The stress level in our case did not affect or determine the performance of acquired skills. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Simulation of the hydraulic performance of highway filter drains through laboratory models and stormwater management tools.

    Science.gov (United States)

    Sañudo-Fontaneda, Luis A; Jato-Espino, Daniel; Lashford, Craig; Coupe, Stephen J

    2017-05-23

    Road drainage is one of the most relevant assets in transport infrastructure due to its inherent influence on traffic management and road safety. Highway filter drains (HFDs), also known as "French Drains", are the main drainage system currently in use in the UK, throughout 7000 km of its strategic road network. Despite being a widespread technique across the whole country, little research has been completed on their design considerations and their subsequent impact on their hydraulic performance, representing a gap in the field. Laboratory experiments have been proven to be a reliable indicator for the simulation of the hydraulic performance of stormwater best management practices (BMPs). In addition to this, stormwater management tools (SMT) have been preferentially chosen as a design tool for BMPs by practitioners from all over the world. In this context, this research aims to investigate the hydraulic performance of HFDs by comparing the results from laboratory simulation and two widely used SMT such as the US EPA's stormwater management model (SWMM) and MicroDrainage®. Statistical analyses were applied to a series of rainfall scenarios simulated, showing a high level of accuracy between the results obtained in laboratory and using SMT as indicated by the high and low values of the Nash-Sutcliffe and R 2 coefficients and root-mean-square error (RMSE) reached, which validated the usefulness of SMT to determine the hydraulic performance of HFDs.

  11. Chinese carless young drivers' self-reported driving behavior and simulated driving performance.

    Science.gov (United States)

    Zhang, Qian; Jiang, Zuhua; Zheng, Dongpeng; Man, Dong; Xu, Xunnan

    2013-01-01

    Carless young drivers refers to those drivers aged between 18 and 25 years who have a driver's license but seldom have opportunities to practice their driving skills because they do not have their own cars. Due to China's lower private car ownership, many young drivers become carless young drivers after licensure, and the safety issue associated with them has raised great concern in China. This study aims to provide initial insight into the self-reported driving behaviors and simulated driving performance of Chinese carless young drivers. Thirty-three carless young drivers and 32 young drivers with their own cars (as a comparison group) participated in this study. A modified Driver Behavior Questionnaire (DBQ) with a 4-factor structure (errors, violations, attention lapses, and memory lapses) was used to study carless young drivers' self-reported driving behaviors. A simulated driving experiment using a low-cost, fixed-base driving simulator was conducted to measure their simulated driving performance (errors, violations, attention lapses, driving maintenance, reaction time, and accidents). Self-reported DBQ outcomes showed that carless young drivers reported similar errors, more attention lapses, fewer memory lapses, and significantly fewer violation behaviors relative to young drivers with their own cars, whereas simulated driving results revealed that they committed significantly more errors, attention lapses, and violation behaviors than the comparison group. Carless young drivers had a lower ability to maintain the stability of speed and lane position, drove more cautiously approaching and passing through red traffic lights, and committed more accidents during simulated driving. A tendency to speed was not found among carless young drivers; their average speed and speeding frequency were all much lower than that of the comparison group. Lifetime mileage was the only significant predictor of carless young drivers' self-reported violations, simulated violations

  12. The effect of metacognitive monitoring feedback on performance in a computer-based training simulation.

    Science.gov (United States)

    Kim, Jung Hyup

    2018-02-01

    This laboratory experiment was designed to study the effect of metacognitive monitoring feedback on performance in a computer-based training simulation. According to prior research on metacognition, the accurate checking of learning is a critical part of improving the quality of human performance. However, only rarely have researchers studied the learning effects of the accurate checking of retrospective confidence judgments (RCJs) during a computer-based military training simulation. In this study, we provided participants feedback screens after they had completed a warning task and identification task in a radar monitoring simulation. There were two groups in this experiment. One group (group A) viewed the feedback screens with the flight path of all target aircraft and the triangular graphs of both RCJ scores and human performance together. The other group (group B) only watched the feedback screens with the flight path of all target aircraft. There was no significant difference in performance improvement between groups A and B for the warning task (Day 1: group A - 0.347, group B - 0.305; Day 2: group A - 0.488, group B - 0.413). However, the identification task yielded a significant difference in performance improvement between these groups (Day 1: group A - 0.174, group B - 0.1555; Day 2: group A - 0.324, group B - 0.199). The results show that debiasing self-judgment of the identification task produces a positive training effect on learners. The findings of this study will be beneficial for designing an advanced instructional strategy in a simulation-based training environment. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Physiological responses and performance in a simulated trampoline gymnastics competition in elite male gymnasts.

    Science.gov (United States)

    Jensen, Peter; Scott, Suzanne; Krustrup, Peter; Mohr, Magni

    2013-01-01

    Physiological responses and performance were examined during and after a simulated trampoline competition (STC). Fifteen elite trampoline gymnasts participated, of which eight completed two routines (EX1 and EX2) and a competition final (EX3). Trampoline-specific activities were quantified by video-analysis. Countermovement jump (CMJ) and 20 maximal trampoline jump (20-MTJ) performances were assessed. Heart rate (HR) and quadriceps muscle temperature (Tm) were recorded and venous blood was drawn. A total of 252 ± 16 jumps were performed during the STC. CMJ performance declined (P trampoline gymnastic competition includes a high number of repeated explosive and energy demanding jumps, which impairs jump performance during and 24 h post-competition.

  14. Microsurgical Performance After Sleep Interruption: A NeuroTouch Simulator Study.

    Science.gov (United States)

    Micko, Alexander; Knopp, Karoline; Knosp, Engelbert; Wolfsberger, Stefan

    2017-10-01

    In times of the ubiquitous debate about doctors' working hour restrictions, it is still questionable if the physician's performance is impaired by high work load and long shifts. In this study, we evaluated the impact of sleep interruption on neurosurgical performance. Ten medical students and 10 neurosurgical residents were tested on the virtual-reality simulator NeuroTouch by performing an identical microsurgical task, well rested (baseline test), and after sleep interruption at night (stress test). Deviation of total score, timing, and excessive force on tissue were evaluated. In addition, vital parameters and self-assessment were analyzed. After sleep interruption, total performance score increased significantly (45.1 vs. 48.7, baseline vs. stress test, P = 0.048) while timing remained stable (10.1 vs. 10.4 minutes for baseline vs. stress test, P > 0.05) for both students and residents. Excessive force decreased in both groups during the stress test for the nondominant hand (P = 0.05). For the dominant hand, an increase of excessive force was encountered in the group of residents (P = 0.05). In contrast to their results, participants of both groups assessed their performance worse during the stress test. In our study, we found an increase of neurosurgical simulator performance in neurosurgical residents and medical students under simulated night shift conditions. Further, microsurgical dexterity remained unchanged. Based on our results and the data in the available literature, we cannot confirm that working hour restrictions will have a positive effect on neurosurgical performance. Copyright © 2017 Elsevier Inc. All rights reserved.

  15. Simulation of storage performance on hydropneumatic driveline in dual hybrid hydraulic passenger car

    Directory of Open Access Journals (Sweden)

    Wasbari Faizil

    2017-01-01

    Full Text Available The charging process is one of the critical processes in the hydro-pneumatic driveline storage system. It converts the kinetic energy of the vehicle braking and coasting to the compression energy. This energy is stored in the storage device called the accumulator. The system is planned to be used on the dual hydro-pneumatic hybrid driveline and applied to a hydraulic hybrid passenger car. The aim of this paper is to find the effect of charging parameters on the storage performance through simulation. Through the storage behaviour, the desirable and optimal sizing of the accumulator can be selected. The paper emphasized on the effect of pressure elevation, pre-charge pressure, effective volume, thermal reaction and required time of the accumulator’s charging process. The circuit of charging process has been designed and simulated by using the hydraulic tool in the Automation Studio software. The simulation results were corroborated through the component specification for data rationality. Through the simulation, it was found that pre-charge pressure had a significant effect on the charging process. It determined the efficiency of the effective volume. The higher the pressure elevation, the higher the effective volume. Nevertheless, the more energy required to compress the nitrogen gas in the bladder. Besides, in term of volume displacement, higher volume displacement reduced charging time and lower the fluid temperature. The simulation had been positively highlighted the critical point in charging process which later on, benefited the sizing process in the component selection specification.

  16. Two methods to simulate intrapulpal pressure: effects upon bonding performance of self-etch adhesives.

    Science.gov (United States)

    Feitosa, V P; Gotti, V B; Grohmann, C V; Abuná, G; Correr-Sobrinho, L; Sinhoreti, M A C; Correr, A B

    2014-09-01

    To evaluate the effects of two methods to simulate physiological pulpal pressure on the dentine bonding performance of two all-in-one adhesives and a two-step self-etch silorane-based adhesive by means of microtensile bond strength (μTBS) and nanoleakage surveys. The self-etch adhesives [G-Bond Plus (GB), Adper Easy Bond (EB) and silorane adhesive (SIL)] were applied to flat deep dentine surfaces from extracted human molars. The restorations were constructed using resin composites Filtek Silorane or Filtek Z350 (3M ESPE). After 24 h using the two methods of simulated pulpal pressure or no pulpal pressure (control groups), the bonded teeth were cut into specimens and submitted to μTBS and silver uptake examination. Results were analysed with two-way anova and Tukey's test (P adhesives. No difference between control and pulpal pressure groups was found for SIL and GB. EB led significant drop (P = 0.002) in bond strength under pulpal pressure. Silver impregnation was increased after both methods of simulated pulpal pressure for all adhesives, and it was similar between the simulated pulpal pressure methods. The innovative method to simulate pulpal pressure behaved similarly to the classic one and could be used as an alternative. The HEMA-free one-step and the two-step self-etch adhesives had acceptable resistance against pulpal pressure, unlike the HEMA-rich adhesive. © 2013 International Endodontic Journal. Published by John Wiley & Sons Ltd.

  17. Performance of uncertainty quantification methodologies and linear solvers in cardiovascular simulations

    Science.gov (United States)

    Seo, Jongmin; Schiavazzi, Daniele; Marsden, Alison

    2017-11-01

    Cardiovascular simulations are increasingly used in clinical decision making, surgical planning, and disease diagnostics. Patient-specific modeling and simulation typically proceeds through a pipeline from anatomic model construction using medical image data to blood flow simulation and analysis. To provide confidence intervals on simulation predictions, we use an uncertainty quantification (UQ) framework to analyze the effects of numerous uncertainties that stem from clinical data acquisition, modeling, material properties, and boundary condition selection. However, UQ poses a computational challenge requiring multiple evaluations of the Navier-Stokes equations in complex 3-D models. To achieve efficiency in UQ problems with many function evaluations, we implement and compare a range of iterative linear solver and preconditioning techniques in our flow solver. We then discuss applications to patient-specific cardiovascular simulation and how the problem/boundary condition formulation in the solver affects the selection of the most efficient linear solver. Finally, we discuss performance improvements in the context of uncertainty propagation. Support from National Institute of Health (R01 EB018302) is greatly appreciated.

  18. Effects of simulated domestic and international air travel on sleep, performance, and recovery for team sports.

    Science.gov (United States)

    Fowler, P; Duffield, R; Vaile, J

    2015-06-01

    The present study examined effects of simulated air travel on physical performance. In a randomized crossover design, 10 physically active males completed a simulated 5-h domestic flight (DOM), 24-h simulated international travel (INT), and a control trial (CON). The mild hypoxia, seating arrangements, and activity levels typically encountered during air travel were simulated in a normobaric, hypoxic altitude room. Physical performance was assessed in the afternoon of the day before (D - 1 PM) and in the morning (D + 1 AM) and afternoon (D + 1 PM) of the day following each trial. Mood states and physiological and perceptual responses to exercise were also examined at these time points, while sleep quantity and quality were monitored throughout each condition. Sleep quantity and quality were significantly reduced during INT compared with CON and DOM (P  0.05). Compared with baseline, physiological and perceptual responses to exercise, and mood states were exacerbated following the INT trial (P sleep disruption during travel and the subsequent exacerbated physiological and perceptual markers of fatigue. © 2014 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  19. Dynamic Performance Comparison for MPPT-PV Systems using Hybrid Pspice/Matlab Simulation

    Science.gov (United States)

    Aouchiche, N.; Becherif, M.; HadjArab, A.; Aitcheikh, M. S.; Ramadan, H. S.; Cheknane, A.

    2016-10-01

    The power generated by solar photovoltaic (PV) module depends on the surrounding irradiance and temperature. This paper presents a hybrid Matlab™/Pspice™ simulation model of PV system, combined with Cadence software SLPS. The hybridization is performed in order to gain the advantages of both simulation tools such as accuracy and efficiency in both Pspice electronic circuit and Matlab™ mathematical modelling respectively. For this purpose, the PV panel and the boost converter are developed using Pspice™ and hybridized with the mathematical Matlab™ model of maximum power point method controller (MPPT) through SLPS. The main objective is verify the significance of using the proposed hybrid simulation techniques in comparing the different MPPT algorithms such as the perturbation and observation (P&O), incremental of conductance (Inc-Cond) and counter reaction voltage using pilot cell (Pilot-Cell). Various simulations are performed under different atmospheric conditions in order to evaluate the dynamic behaviour for the system under study in terms of stability, efficiency and rapidity.

  20. Performance simulation and analysis of a CMOS/nano hybrid nanoprocessor system

    International Nuclear Information System (INIS)

    Cabe, Adam C; Das, Shamik

    2009-01-01

    This paper provides detailed simulation results and analysis of the prospective performance of hybrid CMOS/nanoelectronic processor systems based upon the field-programmable nanowire interconnect (FPNI) architecture. To evaluate this architecture, a complete design was developed for an FPNI implementation using 90 nm CMOS with 15 nm wide nanowire interconnects. Detailed simulations of this design illustrate that critical design choices and tradeoffs exist beyond those specified by the architecture. This includes the selection of the types of junction nanodevices, as well as the implementation of low-level circuits. In particular, the simulation results presented here show that only nanodevices with an 'on/off' current ratio of 200 or more are suitable to produce correct system-level behaviour. Furthermore, the design of the CMOS logic gates in the FPNI system must be customized to accommodate the resistances of both 'on'-state and 'off'-state nanodevices. Using these customized designs together with models of suitable nanodevices, additional simulations demonstrate that, relative to conventional 90 nm CMOS FPGA systems, performance gains can be obtained of up to 70% greater speed or up to a ninefold reduction in energy consumption.

  1. Simulation on following Performance of High-Speed Railway In Situ Testing System

    Directory of Open Access Journals (Sweden)

    Fei-Long Zheng

    2013-01-01

    Full Text Available Subgrade bears both the weight of superstructures and the impacts of running trains. Its stability affects the line smoothness directly, but in situ testing method on it is inadequate. This paper presents a railway roadbed in situ testing device, the key component of which is an excitation hydraulic servo cylinder that can output the static pressure and dynamic pressure simultaneously to simulate the force of the trains to the subgrade. The principle of the excitation system is briefly introduced, and the transfer function of the closed-loop force control system is derived and simulated; that, it shows without control algorithm, the dynamic response is very low and the following performance is quite poor. So, the improvedadaptive model following control (AMFC algorithm based on direct state method is adopted. Then, control block diagram is built and simulated with the input of different waveforms and frequencies. The simulation results show that the system has been greatly improved; the output waveform can follow the input signal much better except for a little distortion when the signal varies severely. And the following performance becomes even better as the load stiffness increases.

  2. Comprehensive Performance Evaluation for Hydrological and Nutrients Simulation Using the Hydrological Simulation Program–Fortran in a Mesoscale Monsoon Watershed, China

    OpenAIRE

    Zhaofu Li; Chuan Luo; Kaixia Jiang; Rongrong Wan; Hengpeng Li

    2017-01-01

    The Hydrological Simulation Program–Fortran (HSPF) is a hydrological and water quality computer model that was developed by the United States Environmental Protection Agency. Comprehensive performance evaluations were carried out for hydrological and nutrient simulation using the HSPF model in the Xitiaoxi watershed in China. Streamflow simulation was calibrated from 1 January 2002 to 31 December 2007 and then validated from 1 January 2008 to 31 December 2010 using daily observed data, and nu...

  3. Ramifications of single-port laparoscopic surgery: measuring differences in task performance using simulation.

    Science.gov (United States)

    Conway, Nathan E; Romanelli, John R; Bush, Ron W; Seymour, Neal E

    2014-02-01

    Single-port laparoscopic surgery imposes unique psychomotor challenges. We used surgical simulation to define performance differences between surgeons with and without single-port clinical experience and examined whether a short course of training resulted in improved performance. Study participants were assigned to 3 groups: resident group (RES), experienced laparoscopic surgeons with (SP) and without (LAP) prior single-port laparoscopic experience. Participants performed the Fundamentals of Laparoscopic Surgery precision cutting task on a ProMIS trainer through conventional ports or with articulating instruments via a SILS Port (Covidien, Inc). Two iterations of each method were performed. Then, 6 residents performed 10 successive single-port iterations to assess the effect of practice on task performance. The SP group had faster task times for both laparoscopic (P = .0486) and single-port (P = .0238) methods. The LAP group had longer path lengths for the single-port task than for the laparoscopic task (P = .03). The RES group was slower (P = .0019), with longer path length (P = .0010) but with greater smoothness (P = .0186) on the single-port task than the conventional laparoscopic task. Resident performance task time (P = .005) and smoothness (P = .045) improved with successive iterations. Our data show that surgeons with clinical single-port surgery experience perform a simulated single-port surgical task better than inexperienced single-port surgeons. Furthermore, this performance is comparable to that achieved with conventional laparoscopic techniques. Performance of residents declined dramatically when confronted with the challenges of the single-port task but improved with practice. These results suggest a role for lab-based single-port training.

  4. Self-rotations in simulated microgravity: performance effects of strategy training.

    Science.gov (United States)

    Stirling, Leia; Newman, Dava; Willcox, Karen

    2009-01-01

    This research studies reorientation methodologies in a simulated microgravity environment using an experimental framework to reduce astronaut adaptation time and provide for a safety countermeasure during extravehicular activity. There were 20 subjects (10 men, 10 women, mean age of 23.6 +/- 3.5) who were divided into 2 groups, fully trained and minimally trained, which determined the amount of motion strategy training received. Subjects performed a total of 48 rotations about their pitch, roll, and yaw axes in a suspension system that simulated microgravity. In each trial subjects either rotated 90 degrees in pitch, 90 degrees in roll, or 180 degrees in yaw. Experimental measures include subject coordination, performance time, cognitive workload assessments, and qualitative motion control strategies. Subjects in the fully trained group had better initial performance with respect to performance time and workload scores for the pitch and yaw rotations. Further, trained subjects reached a steady-state performance time in fewer trials than those with minimal training. The subjects with minimal training tended to use motions that were common in an Earth environment since no technique was provided. For roll rotations they developed motions that would have led to significant off-axis (pitch and yaw) rotations in a true microgravity environment. We have shown that certain body axes are easier to rotate about than others and that fully trained subjects had an easier time performing the body rotations than the minimally trained subjects. This study has provided the groundwork for the development of an astronaut motion-control training program.

  5. Event-related potentials and secondary task performance during simulated driving.

    Science.gov (United States)

    Wester, A E; Böcker, K B E; Volkerts, E R; Verster, J C; Kenemans, J L

    2008-01-01

    Inattention and distraction account for a substantial number of traffic accidents. Therefore, we examined the impact of secondary task performance (an auditory oddball task) on a primary driving task (lane keeping). Twenty healthy participants performed two 20-min tests in the Divided Attention Steering Simulator (DASS). The visual secondary task of the DASS was replaced by an auditory oddball task to allow recording of brain activity. The driving task and the secondary (distracting) oddball task were presented in isolation and simultaneously, to assess their mutual interference. In addition to performance measures (lane keeping in the primary driving task and reaction speed in the secondary oddball task), brain activity, i.e. event-related potentials (ERPs), was recorded. Performance parameters on the driving test and the secondary oddball task did not differ between performance in isolation and simultaneous performance. However, when both tasks were performed simultaneously, reaction time variability increased in the secondary oddball task. Analysis of brain activity indicated that ERP amplitude (P3a amplitude) related to the secondary task, was significantly reduced when the task was performed simultaneously with the driving test. This study shows that when performing a simple secondary task during driving, performance of the driving task and this secondary task are both unaffected. However, analysis of brain activity shows reduced cortical processing of irrelevant, potentially distracting stimuli from the secondary task during driving.

  6. Effect of Engaging Trainees by Assessing Peer Performance: A Randomised Controlled Trial Using Simulated Patient Scenarios

    Directory of Open Access Journals (Sweden)

    Charlotte Loumann Krogh

    2014-01-01

    Full Text Available Introduction. The aim of this study was to explore the learning effect of engaging trainees by assessing peer performance during simulation-based training. Methods. Eighty-four final year medical students participated in the study. The intervention involved trainees assessing peer performance during training. Outcome measures were in-training performance and performance, both of which were measured two weeks after the course. Trainees’ performances were videotaped and assessed by two expert raters using a checklist that included a global rating. Trainees’ satisfaction with the training was also evaluated. Results. The intervention group obtained a significantly higher overall in-training performance score than the control group: mean checklist score 20.87 (SD 2.51 versus 19.14 (SD 2.65 P=0.003 and mean global rating 3.25 SD (0.99 versus 2.95 (SD 1.09 P=0.014. Postcourse performance did not show any significant difference between the two groups. Trainees who assessed peer performance were more satisfied with the training than those who did not: mean 6.36 (SD 1.00 versus 5.74 (SD 1.33 P=0.025. Conclusion. Engaging trainees in the assessment of peer performance had an immediate effect on in-training performance, but not on the learning outcome measured two weeks later. Trainees had a positive attitude towards the training format.

  7. LISA Pathfinder E2E performance simulation: optical and self-gravity stability analysis

    Science.gov (United States)

    Brandt, N.; Fichter, W.; Kersten, M.; Lucarelli, S.; Montemurro, F.

    2005-05-01

    End-to-end (E2E) modelling and simulation, i.e. verifying the science performance of LISA Pathfinder (spacecraft and payload), is mandatory in order to minimize mission risks. In this paper, focus is on two particular applications of the E2E performance simulator currently being developed at EADS Astrium GmbH: the opto-dynamical stability and the self-gravity disturbance stability analysis. The E2E models applied here comprise the opto-dynamical modelling of the optical metrology systems (OMS) laser interferometry, the thermo-elastic distortion modelling of the OMS optical elements and the self-gravity disturbance model accounting for structural distortions. Preliminary analysis results are presented in detail, identifying shortcomings of the current LISA technology package (LTP) mounting baseline. As a consequence, the design is now being revised.

  8. LISA Pathfinder E2E performance simulation: optical and self-gravity stability analysis

    International Nuclear Information System (INIS)

    Brandt, N; Fichter, W; Kersten, M; Lucarelli, S; Montemurro, F

    2005-01-01

    End-to-end (E2E) modelling and simulation, i.e. verifying the science performance of LISA Pathfinder (spacecraft and payload), is mandatory in order to minimize mission risks. In this paper, focus is on two particular applications of the E2E performance simulator currently being developed at EADS Astrium GmbH: the opto-dynamical stability and the self-gravity disturbance stability analysis. The E2E models applied here comprise the opto-dynamical modelling of the optical metrology systems (OMS) laser interferometry, the thermo-elastic distortion modelling of the OMS optical elements and the self-gravity disturbance model accounting for structural distortions. Preliminary analysis results are presented in detail, identifying shortcomings of the current LISA technology package (LTP) mounting baseline. As a consequence, the design is now being revised

  9. Simulation and experiment on the thermal performance of U-vertical ground coupled heat exchanger

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xinguo; Chen, Zhihao; Zhao, Jun [Department of Thermal Engineering, School of Mechanical Engineering, Tianjin University, Tianjin 300072 (China)

    2006-10-15

    This paper presented both the numerical simulations and experiments on the thermal performance of U-vertical ground coupled heat exchanger (UGCHE). The variation of the ground temperature and heat balance of the system were analyzed and compared in different operation modes in the numerical simulation. Experiments on the operation performance of the ground-coupled heat pump (GCHP) with the UGCHE were carried out. It shows that the ground source can be used as the heat source/sink for GCHP systems to have higher efficiency in saving energy. To preserve the ground resource for the sustainable utilization as heat source/sink, the heat emitted to ground and heat extracted from ground should be balanced. (author)

  10. Performance of high-rate TRD prototypes for the CBM experiment in test beam and simulation

    Energy Technology Data Exchange (ETDEWEB)

    Klein-Boesing, Melanie [Institut fuer Kernphysik, Muenster (Germany)

    2008-07-01

    The goal of the future Compressed Baryonic Matter (CBM) experiment is to explore the QCD phase diagram in the region of high baryon densities not covered by other experiments. Among other detectors, it will employ a Transition Radiation Detector (TRD) for tracking of charged particles and electron identification. To meet the demands for tracking and for electron identification at large particle densities and very high interaction rates, high efficiency TRD prototypes have been developed. These prototypes with double-sided pad plane electrodes based on Multiwire Proportional Chambers (MWPC) have been tested at GSI and implemented in the simulation framework of CBM. Results of the performance in a test beam and in simulations are shown. In addition, we present a study of the performance of CBM for electron identification and dilepton reconstruction with this new detector layout.

  11. A more realistic simulation of the performance of the infra-sound monitoring network

    International Nuclear Information System (INIS)

    Le Pichon, A.; Vergoz, J.; Blanc, E.

    2008-01-01

    The first global maps showing the performance of the infra-sound network of the international monitoring system were set in the nineties. Recent measurement of the background noise by the 36 operating stations combined with advanced models of wind give now a more realistic mapping. It has become possible to validate simulations by measuring real events. For instance the explosion that happened in March 2008 in an ammunition storehouse in Albania was detected till Zalesovo (Russia) 4920 km away. These new simulations confirm the detection capability of the network to detect and localize atmospheric explosions whose energy is over 1 kt. It is also shown that the detection performance are very sensitive to both time and places. (A.C.)

  12. Measured and simulated performance of Compton-suppressed TIGRESS HPGe clover detectors

    Science.gov (United States)

    Schumaker, M. A.; Hackman, G.; Pearson, C. J.; Svensson, C. E.; Andreoiu, C.; Andreyev, A.; Austin, R. A. E.; Ball, G. C.; Bandyopadhyay, D.; Boston, A. J.; Chakrawarthy, R. S.; Churchman, R.; Drake, T. E.; Finlay, P.; Garrett, P. E.; Grinyer, G. F.; Hyland, B.; Jones, B.; Maharaj, R.; Morton, A. C.; Phillips, A. A.; Sarazin, F.; Scraggs, H. C.; Smith, M. B.; Valiente-Dobón, J. J.; Waddington, J. C.; Watters, L. M.

    2007-01-01

    Tests of the performance of a 32-fold segmented HPGe clover detector coupled to a 20-fold segmented Compton-suppression shield, which form a prototype element of the TRIUMF-ISAC Gamma-Ray Escape-Suppressed Spectrometer (TIGRESS), have been made. Peak-to-total ratios and relative efficiencies have been measured for a variety of γ-ray energies. These measurements were used to validate a GEANT4 simulation of the TIGRESS detectors, which was then used to create a simulation of the full 12-detector array. Predictions of the expected performance of TIGRESS are presented. These predictions indicate that TIGRESS will be capable, for single 1 MeV γ rays, of absolute detection efficiencies of 17% and 9.4%, and peak-to-total ratios of 54% and 61% for the "high-efficiency" and "optimized peak-to-total" configurations of the array, respectively.

  13. Mental abilities and performance efficacy under a simulated 480 meters helium-oxygen saturation diving

    Directory of Open Access Journals (Sweden)

    gonglin ehou

    2015-07-01

    Full Text Available Stress in extreme environment severely disrupts human physiology and mental abilities. The present study investigated the cognition and performance efficacy of four divers during a simulated 480 meters helium-oxygen saturation diving. We analyzed the spatial memory, 2D/3D mental rotation functioning, grip strength, and hand-eye coordination ability in four divers during the 0 – 480 meters compression and decompression processes of the simulated diving. The results showed that except for its mild decrease on grip strength, the high atmosphere pressure condition significantly impaired the hand-eye coordination (especially at 300 meters, the reaction time and correct rate of mental rotation, as well as the spatial memory (especially as 410 meters, showing high individual variability. We conclude that the human cognition and performance efficacy are significantly affected during deep water saturation diving.

  14. A Dynamic Simulation Model of Organizational Culture and Business Strategy Effects on Performance

    Science.gov (United States)

    Trivellas, Panagiotis; Reklitis, Panagiotis; Konstantopoulos, Nikolaos

    2007-12-01

    In the past two decades, organizational culture literature has gained tremendous interest for both academic and practitioners. This is based not only on the suggestion that culture is related to performance, but also on the view that it is subject of direct managerial control and manipulation to the desired direction. In the present paper, we adopt Competing Values Framework (CVF) to operationalise organizational culture and Porter's typology to conceptualize business strategy (cost leadership, innovative and marketing differentiation, and focus). Although simulation of social events is a quite difficult task, since there are so many considerations (not all well understood) involved, in the present study we developed a dynamic model to simulate the organizational culture and strategy effects on financial performance. Data obtained from a six-year survey in the banking sector of a European developing economy was used for the proposed dynamic model development.

  15. Assessment of Spatial Navigation and Docking Performance During Simulated Rover Tasks

    Science.gov (United States)

    Wood, S. J.; Dean, S. L.; De Dios, Y. E.; Moore, S. T.

    2010-01-01

    INTRODUCTION: Following long-duration exploration transits, pressurized rovers will enhance surface mobility to explore multiple sites across Mars and other planetary bodies. Multiple rovers with docking capabilities are envisioned to expand the range of exploration. However, adaptive changes in sensorimotor and cognitive function may impair the crew s ability to safely navigate and perform docking tasks shortly after transition to the new gravitoinertial environment. The primary goal of this investigation is to quantify post-flight decrements in spatial navigation and docking performance during a rover simulation. METHODS: Eight crewmembers returning from the International Space Station will be tested on a motion simulator during four pre-flight and three post-flight sessions over the first 8 days following landing. The rover simulation consists of a serial presentation of discrete tasks to be completed within a scheduled 10 min block. The tasks are based on navigating around a Martian outpost spread over a 970 sq m terrain. Each task is subdivided into three components to be performed as quickly and accurately as possible: (1) Perspective taking: Subjects use a joystick to indicate direction of target after presentation of a map detailing current orientation and location of the rover with the task to be performed. (2) Navigation: Subjects drive the rover to the desired location while avoiding obstacles. (3) Docking: Fine positioning of the rover is required to dock with another object or align a camera view. Overall operator proficiency will be based on how many tasks the crewmember can complete during the 10 min time block. EXPECTED RESULTS: Functionally relevant testing early post-flight will develop evidence regarding the limitations to early surface operations and what countermeasures are needed. This approach can be easily adapted to a wide variety of simulated vehicle designs to provide sensorimotor assessments for other operational and civilian populations.

  16. A comparison of the effect of mobile phone use and alcohol consumption on driving simulation performance.

    Science.gov (United States)

    Leung, Sumie; Croft, Rodney J; Jackson, Melinda L; Howard, Mark E; McKenzie, Raymond J

    2012-01-01

    The present study compared the effects of a variety of mobile phone usage conditions to different levels of alcohol intoxication on simulated driving performance and psychomotor vigilance. Twelve healthy volunteers participated in a crossover design in which each participant completed a simulated driving task on 2 days, separated by a 1-week washout period. On the mobile phone day, participants performed the simulated driving task under each of 4 conditions: no phone usage, a hands-free naturalistic conversation, a hands-free cognitively demanding conversation, and texting. On the alcohol day, participants performed the simulated driving task at four different blood alcohol concentration (BAC) levels: 0.00, 0.04, 0.07, and 0.10. Driving performance was assessed by variables including time within target speed range, time spent speeding, braking reaction time, speed deviation, and lateral lane position deviation. In the BAC 0.07 and 0.10 alcohol conditions, participants spent less time in the target speed range and more time speeding and took longer to brake in the BAC 0.04, 0.07, and 0.10 than in the BAC 0.00 condition. In the mobile phone condition, participants took longer to brake in the natural hands-free conversation, cognitively demanding hands-free conversation and texting conditions and spent less time in the target speed range and more time speeding in the cognitively demanding, hands-free conversation, and texting conditions. When comparing the 2 conditions, the naturalistic conversation was comparable to the legally permissible BAC level (0.04), and the cognitively demanding and texting conversations were similar to the BAC 0.07 to 0.10 results. The findings of the current laboratory study suggest that very simple conversations on a mobile phone may not represent a significant driving risk (compared to legally permissible BAC levels), whereas cognitively demanding, hands-free conversation, and particularly texting represent significant risks to driving.

  17. Improved nondominant hand performance on a laparoscopic virtual reality simulator after playing the Nintendo Wii.

    Science.gov (United States)

    Middleton, Kellie K; Hamilton, Travis; Tsai, Pei-Chien; Middleton, Dana B; Falcone, John L; Hamad, Giselle

    2013-11-01

    Video games have been shown to improve eye-hand coordination, spatial visualization, manual dexterity, and rapid mental processing, which are important in the acquisition of laparoscopic skills. This study investigated the relationship between playing Nintendo(®) Wii™ and virtual reality (VR) laparoscopic surgery simulator performance. We hypothesized that playing the Wii would improve surgical skills performance on a VR laparoscopic simulator and hoped to elucidate which tasks, in particular, would be most beneficial for nondominant hand training. This was a single-blinded, randomized, prospective study conducted with 23 student volunteers. VR laparoscopic skills were assessed at baseline on a Simbionix LapMentor™ Surgical Simulator (Simbionix Ltd., Israel) and after the gaming period of 2 weeks. Simulator performance metrics were compared between groups using nonparametric statistics and an alpha of 0.05. Compared with the control group, the Wii-playing group demonstrated greater improvement of six measures, including accuracy on the eye-hand coordination task (p = 0.04), faster completion time (p = 0.04), decreased number of left-handed movements (p = 0.03), decreased left handed total path length (p = 0.03), decreased total number of grasping attempts (p = 0.04), and improved left-handed economy of movement (p = 0.05) for the bimanual clipping and grasping task. When comparing the number of measures improved upon by the Wii-playing group and the control group for all three tasks, the Wii-playing group consistently outperformed the control group in 18 measures compared with the control group's improvement in 6. This study further characterizes the association between video game playing and surgical performance. Improvements following the intervention were made in the most basic of surgical skills, most notably with the nondominant hand, suggesting that short-term playing of the Wii could improve bimanual dexterity and expedite the acquisition of basic

  18. Optimal Spatial Subdivision method for improving geometry navigation performance in Monte Carlo particle transport simulation

    International Nuclear Information System (INIS)

    Chen, Zhenping; Song, Jing; Zheng, Huaqing; Wu, Bin; Hu, Liqin

    2015-01-01

    Highlights: • The subdivision combines both advantages of uniform and non-uniform schemes. • The grid models were proved to be more efficient than traditional CSG models. • Monte Carlo simulation performance was enhanced by Optimal Spatial Subdivision. • Efficiency gains were obtained for realistic whole reactor core models. - Abstract: Geometry navigation is one of the key aspects of dominating Monte Carlo particle transport simulation performance for large-scale whole reactor models. In such cases, spatial subdivision is an easily-established and high-potential method to improve the run-time performance. In this study, a dedicated method, named Optimal Spatial Subdivision, is proposed for generating numerically optimal spatial grid models, which are demonstrated to be more efficient for geometry navigation than traditional Constructive Solid Geometry (CSG) models. The method uses a recursive subdivision algorithm to subdivide a CSG model into non-overlapping grids, which are labeled as totally or partially occupied, or not occupied at all, by CSG objects. The most important point is that, at each stage of subdivision, a conception of quality factor based on a cost estimation function is derived to evaluate the qualities of the subdivision schemes. Only the scheme with optimal quality factor will be chosen as the final subdivision strategy for generating the grid model. Eventually, the model built with the optimal quality factor will be efficient for Monte Carlo particle transport simulation. The method has been implemented and integrated into the Super Monte Carlo program SuperMC developed by FDS Team. Testing cases were used to highlight the performance gains that could be achieved. Results showed that Monte Carlo simulation runtime could be reduced significantly when using the new method, even as cases reached whole reactor core model sizes

  19. Effects of chewing gum on driving performance as evaluated by the STISIM driving simulator

    OpenAIRE

    Yoo, Ingyu; Kim, Eun-Joo; Lee, Joo-Hyun

    2015-01-01

    [Purpose] The purpose of this study was to determine the effects of chewing gum on driving performance in a driving simulator. [Subjects] In total, 26 young licensed drivers participated. [Methods] The driving scenario was typical of an urban environment: a single-carriageway, two-way road consisting of a mix of curved and straight sections, with considerable levels of traffic, pedestrians, and parked cars. Mean distance driven above the speed limit, lane position, mean distance driven across...

  20. COMSOL-PHREEQC: a tool for high performance numerical simulation of reactive transport phenomena

    International Nuclear Information System (INIS)

    Nardi, Albert; Vries, Luis Manuel de; Trinchero, Paolo; Idiart, Andres; Molinero, Jorge

    2012-01-01

    this tool. An example of 3D reactive transport simulations in clay material is shown to illustrate the capabilities and potential of the numerical tool. The example is based on the thermo-hydrochemical (THC) evolution of a deposition hole in the SKB KBS-3V concept of HLRW repository. Figure 1 shows the entire model domain of the performed THC simulation. Figure 2 shows the numerical FE refined mesh used in the clayey materials of the backfilled gallery and deposition hole, where variable saturated flow and reactive transport simulations were performed to study the expected geochemical behaviour of the clay barriers. (authors)

  1. Teamwork skills, shared mental models, and performance in simulated trauma teams: an independent group design

    Directory of Open Access Journals (Sweden)

    Westli Heidi

    2010-08-01

    Full Text Available Abstract Background Non-technical skills are seen as an important contributor to reducing adverse events and improving medical management in healthcare teams. Previous research on the effectiveness of teams has suggested that shared mental models facilitate coordination and team performance. The purpose of the study was to investigate whether demonstrated teamwork skills and behaviour indicating shared mental models would be associated with observed improved medical management in trauma team simulations. Methods Revised versions of the 'Anesthetists' Non-Technical Skills Behavioural marker system' and 'Anti-Air Teamwork Observation Measure' were field tested in moment-to-moment observation of 27 trauma team simulations in Norwegian hospitals. Independent subject matter experts rated medical management in the teams. An independent group design was used to explore differences in teamwork skills between higher-performing and lower-performing teams. Results Specific teamwork skills and behavioural markers were associated with indicators of good team performance. Higher and lower-performing teams differed in information exchange, supporting behaviour and communication, with higher performing teams showing more effective information exchange and communication, and less supporting behaviours. Behavioural markers of shared mental models predicted effective medical management better than teamwork skills. Conclusions The present study replicates and extends previous research by providing new empirical evidence of the significance of specific teamwork skills and a shared mental model for the effective medical management of trauma teams. In addition, the study underlines the generic nature of teamwork skills by demonstrating their transferability from different clinical simulations like the anaesthesia environment to trauma care, as well as the potential usefulness of behavioural frequency analysis in future research on non-technical skills.

  2. Sleep restriction during simulated wildfire suppression: effect on physical task performance.

    Directory of Open Access Journals (Sweden)

    Grace Vincent

    Full Text Available OBJECTIVES: To examine the effects of sleep restriction on firefighters' physical task performance during simulated wildfire suppression. METHODS: Thirty-five firefighters were matched and randomly allocated to either a control condition (8-hour sleep opportunity, n = 18 or a sleep restricted condition (4-hour sleep opportunity, n = 17. Performance on physical work tasks was evaluated across three days. In addition, heart rate, core temperature, and worker activity were measured continuously. Rate of perceived and exertion and effort sensation were evaluated during the physical work periods. RESULTS: There were no differences between the sleep-restricted and control groups in firefighters' task performance, heart rate, core temperature, or perceptual responses during self-paced simulated firefighting work tasks. However, the sleep-restricted group were less active during periods of non-physical work compared to the control group. CONCLUSIONS: Under self-paced work conditions, 4 h of sleep restriction did not adversely affect firefighters' performance on physical work tasks. However, the sleep-restricted group were less physically active throughout the simulation. This may indicate that sleep-restricted participants adapted their behaviour to conserve effort during rest periods, to subsequently ensure they were able to maintain performance during the firefighter work tasks. This work contributes new knowledge to inform fire agencies of firefighters' operational capabilities when their sleep is restricted during multi-day wildfire events. The work also highlights the need for further research to explore how sleep restriction affects physical performance during tasks of varying duration, intensity, and complexity.

  3. Durango: Scalable Synthetic Workload Generation for Extreme-Scale Application Performance Modeling and Simulation

    Energy Technology Data Exchange (ETDEWEB)

    Carothers, Christopher D. [Rensselaer Polytechnic Institute (RPI); Meredith, Jeremy S. [ORNL; Blanco, Marc [Rensselaer Polytechnic Institute (RPI); Vetter, Jeffrey S. [ORNL; Mubarak, Misbah [Argonne National Laboratory; LaPre, Justin [Rensselaer Polytechnic Institute (RPI); Moore, Shirley V. [ORNL

    2017-05-01

    Performance modeling of extreme-scale applications on accurate representations of potential architectures is critical for designing next generation supercomputing systems because it is impractical to construct prototype systems at scale with new network hardware in order to explore designs and policies. However, these simulations often rely on static application traces that can be difficult to work with because of their size and lack of flexibility to extend or scale up without rerunning the original application. To address this problem, we have created a new technique for generating scalable, flexible workloads from real applications, we have implemented a prototype, called Durango, that combines a proven analytical performance modeling language, Aspen, with the massively parallel HPC network modeling capabilities of the CODES framework.Our models are compact, parameterized and representative of real applications with computation events. They are not resource intensive to create and are portable across simulator environments. We demonstrate the utility of Durango by simulating the LULESH application in the CODES simulation environment on several topologies and show that Durango is practical to use for simulation without loss of fidelity, as quantified by simulation metrics. During our validation of Durango's generated communication model of LULESH, we found that the original LULESH miniapp code had a latent bug where the MPI_Waitall operation was used incorrectly. This finding underscores the potential need for a tool such as Durango, beyond its benefits for flexible workload generation and modeling.Additionally, we demonstrate the efficacy of Durango's direct integration approach, which links Aspen into CODES as part of the running network simulation model. Here, Aspen generates the application-level computation timing events, which in turn drive the start of a network communication phase. Results show that Durango's performance scales well when

  4. Virtual reality, ultrasound-guided liver biopsy simulator: development and performance discrimination

    Science.gov (United States)

    Johnson, S J; Hunt, C M; Woolnough, H M; Crawshaw, M; Kilkenny, C; Gould, D A; England, A; Sinha, A; Villard, P F

    2012-01-01

    Objectives The aim of this article was to identify and prospectively investigate simulated ultrasound-guided targeted liver biopsy performance metrics as differentiators between levels of expertise in interventional radiology. Methods Task analysis produced detailed procedural step documentation allowing identification of critical procedure steps and performance metrics for use in a virtual reality ultrasound-guided targeted liver biopsy procedure. Consultant (n=14; male=11, female=3) and trainee (n=26; male=19, female=7) scores on the performance metrics were compared. Ethical approval was granted by the Liverpool Research Ethics Committee (UK). Independent t-tests and analysis of variance (ANOVA) investigated differences between groups. Results Independent t-tests revealed significant differences between trainees and consultants on three performance metrics: targeting, p=0.018, t=−2.487 (−2.040 to −0.207); probe usage time, p = 0.040, t=2.132 (11.064 to 427.983); mean needle length in beam, p=0.029, t=−2.272 (−0.028 to −0.002). ANOVA reported significant differences across years of experience (0–1, 1–2, 3+ years) on seven performance metrics: no-go area touched, p=0.012; targeting, p=0.025; length of session, p=0.024; probe usage time, p=0.025; total needle distance moved, p=0.038; number of skin contacts, p<0.001; total time in no-go area, p=0.008. More experienced participants consistently received better performance scores on all 19 performance metrics. Conclusion It is possible to measure and monitor performance using simulation, with performance metrics providing feedback on skill level and differentiating levels of expertise. However, a transfer of training study is required. PMID:21304005

  5. Prior video game utilization is associated with improved performance on a robotic skills simulator.

    Science.gov (United States)

    Harbin, Andrew C; Nadhan, Kumar S; Mooney, James H; Yu, Daohai; Kaplan, Joshua; McGinley-Hence, Nora; Kim, Andrew; Gu, Yiming; Eun, Daniel D

    2017-09-01

    Laparoscopic surgery and robotic surgery, two forms of minimally invasive surgery (MIS), have recently experienced a large increase in utilization. Prior studies have shown that video game experience (VGE) may be associated with improved laparoscopic surgery skills; however, similar data supporting a link between VGE and proficiency on a robotic skills simulator (RSS) are lacking. The objective of our study is to determine whether volume or timing of VGE had any impact on RSS performance. Pre-clinical medical students completed a comprehensive questionnaire detailing previous VGE across several time periods. Seventy-five subjects were ultimately evaluated in 11 training exercises on the daVinci Si Skills Simulator. RSS skill was measured by overall score, time to completion, economy of motion, average instrument collision, and improvement in Ring Walk 3 score. Using the nonparametric tests and linear regression, these metrics were analyzed for systematic differences between non-users, light, and heavy video game users based on their volume of use in each of the following four time periods: past 3 months, past year, past 3 years, and high school. Univariate analyses revealed significant differences between heavy and non-users in all five performance metrics. These trends disappeared as the period of VGE went further back. Our study showed a positive association between video game experience and robotic skills simulator performance that is stronger for more recent periods of video game use. The findings may have important implications for the evolution of robotic surgery training.

  6. Theory and validation of a liquid radiation filter greenhouse simulation for performance prediction

    International Nuclear Information System (INIS)

    Feuermann, D.; Kopel, R.; Zeroni, M.; Levi, S.; Gale, J.

    1997-01-01

    A greenhouse is described which has a selectively absorbing liquid radiation filter (LRF) circulating in double layered cladding. The filter removes much of the near infrared wave band of solar radiation (700 nm) while transmitting most of the photosynthetic radiation (400-700 nm). This greatly reduces the heat input to the greenhouse and, by transferring heat from day to night, facilitates better temperature control. This is particularly important for CO2 fertilization, which requires that the greenhouse should remain closed during daylight hours. A computer simulation model was developed to study the relationship between design parameters of such a LRF greenhouse and its thermal performance under different climatic conditions. The model was based on a small number of governing equations describing the major physical phenomena responsible for the greenhouse climate. Validation of the simulation was performed with data from a 330 m2 LRF greenhouse, operating in the Negev (Israel) desert highlands. The predicted greenhouse temperatures were found to agree with measured values to within one to two degrees Celsius. Performances of a LRF and a conventional greenhouse were compared using the simulation and hourly meteorological data for central Israel. For the summer season of May to October, the number of daylight hours during which the LRF greenhouse could remain closed was larger by about two-thirds than that of the conventional greenhouse

  7. High performance simulation for the Silva project using the tera computer

    Energy Technology Data Exchange (ETDEWEB)

    Bergeaud, V.; La Hargue, J.P.; Mougery, F. [CS Communication and Systemes, 92 - Clamart (France); Boulet, M.; Scheurer, B. [CEA Bruyeres-le-Chatel, 91 - Bruyeres-le-Chatel (France); Le Fur, J.F.; Comte, M.; Benisti, D.; Lamare, J. de; Petit, A. [CEA Saclay, 91 - Gif sur Yvette (France)

    2003-07-01

    In the context of the SILVA Project (Atomic Vapor Laser Isotope Separation), numerical simulation of the plant scale propagation of laser beams through uranium vapour was a great challenge. The PRODIGE code has been developed to achieve this goal. Here we focus on the task of achieving high performance simulation on the TERA computer. We describe the main issues for optimizing the parallelization of the PRODIGE code on TERA. Thus, we discuss advantages and drawbacks of the implemented diagonal parallelization scheme. As a consequence, it has been found fruitful to fit out the code in three aspects: memory allocation, MPI communications and interconnection network bandwidth usage. We stress out the interest of MPI/IO in this context and the benefit obtained for production computations on TERA. Finally, we shall illustrate our developments. We indicate some performance measurements reflecting the good parallelization properties of PRODIGE on the TERA computer. The code is currently used for demonstrating the feasibility of the laser propagation at a plant enrichment level and for preparing the 2003 Menphis experiment. We conclude by emphasizing the contribution of high performance TERA simulation to the project. (authors)

  8. Cell-element simulations to optimize the performance of osmotic processes in porous membranes

    KAUST Repository

    Calo, Victor M.

    2018-05-11

    We present a new module of the software tool PoreChem for 3D simulations of osmotic processes at the cell-element scale. We consider the most general fully coupled model (see e.g., Sagiv and Semiat (2011)) in 3D to evaluate the impact on the membrane performance of both internal and external concentration polarization, which occurs in a cell-element for different operational conditions. The model consists of the Navier–Stokes–Brinkman system to describe the free fluid flow and the flow within the membrane with selective and support layers, a convection–diffusion equation to describe the solute transport, and nonlinear interface conditions to fully couple these equations. First, we briefly describe the mathematical model and discuss the discretization of the continuous model, the iterative solution, and the software implementation. Then, we present the analytical and numerical validation of the simulation tool. Next, we perform and discuss numerical simulations for a case study. The case study concerns the design of a cell element for the forward osmosis experiments. Using the developed software tool we qualitatively and quantitatively investigate the performance of a cell element that we designed for laboratory experiments of forward osmosis, and discuss the differences between the numerical solutions obtained with the full 3D and reduced 2D models. Finally, we demonstrate how the software enables investigating membrane heterogeneities.

  9. High performance simulation for the Silva project using the tera computer

    International Nuclear Information System (INIS)

    Bergeaud, V.; La Hargue, J.P.; Mougery, F.; Boulet, M.; Scheurer, B.; Le Fur, J.F.; Comte, M.; Benisti, D.; Lamare, J. de; Petit, A.

    2003-01-01

    In the context of the SILVA Project (Atomic Vapor Laser Isotope Separation), numerical simulation of the plant scale propagation of laser beams through uranium vapour was a great challenge. The PRODIGE code has been developed to achieve this goal. Here we focus on the task of achieving high performance simulation on the TERA computer. We describe the main issues for optimizing the parallelization of the PRODIGE code on TERA. Thus, we discuss advantages and drawbacks of the implemented diagonal parallelization scheme. As a consequence, it has been found fruitful to fit out the code in three aspects: memory allocation, MPI communications and interconnection network bandwidth usage. We stress out the interest of MPI/IO in this context and the benefit obtained for production computations on TERA. Finally, we shall illustrate our developments. We indicate some performance measurements reflecting the good parallelization properties of PRODIGE on the TERA computer. The code is currently used for demonstrating the feasibility of the laser propagation at a plant enrichment level and for preparing the 2003 Menphis experiment. We conclude by emphasizing the contribution of high performance TERA simulation to the project. (authors)

  10. Performance of informative priors skeptical of large treatment effects in clinical trials: A simulation study.

    Science.gov (United States)

    Pedroza, Claudia; Han, Weilu; Thanh Truong, Van Thi; Green, Charles; Tyson, Jon E

    2018-01-01

    One of the main advantages of Bayesian analyses of clinical trials is their ability to formally incorporate skepticism about large treatment effects through the use of informative priors. We conducted a simulation study to assess the performance of informative normal, Student- t, and beta distributions in estimating relative risk (RR) or odds ratio (OR) for binary outcomes. Simulation scenarios varied the prior standard deviation (SD; level of skepticism of large treatment effects), outcome rate in the control group, true treatment effect, and sample size. We compared the priors with regards to bias, mean squared error (MSE), and coverage of 95% credible intervals. Simulation results show that the prior SD influenced the posterior to a greater degree than the particular distributional form of the prior. For RR, priors with a 95% interval of 0.50-2.0 performed well in terms of bias, MSE, and coverage under most scenarios. For OR, priors with a wider 95% interval of 0.23-4.35 had good performance. We recommend the use of informative priors that exclude implausibly large treatment effects in analyses of clinical trials, particularly for major outcomes such as mortality.

  11. FDTD simulations to assess the performance of CFMA-434 applicators for superficial hyperthermia.

    Science.gov (United States)

    Kok, H Petra; De Greef, Martijn; Correia, Davi; Vörding, Paul J Zum Vörde Sive; Van Stam, Gerard; Gelvich, Edward A; Bel, Arjan; Crezee, Johannes

    2009-01-01

    Contact flexible microstrip applicators (CFMA), operating at 434 MHz, are applied at the Academic Medical Center (AMC) for superficial hyperthermia (e.g. chest wall recurrences and melanoma). This paper investigates the performance of CFMA, evaluating the stability of the specific absorption rate (SAR) distribution, effective heating depth (EHD) and effective field size (EFS) under different conditions. Simulations were performed using finite differences and were compared to existing measurement data, performed using a rectangular phantom with a superficial fat-equivalent layer of 1 cm and filled with saline solution. The electrode plates of the applicators measure approximately 7 x 20, 29 x 21 and 20 x 29 cm(2). Bolus thickness varied between 1 and 2 cm. The impact of the presence of possible air layers between the rubber frame and the electrodes on the SAR distribution was investigated. The EHD was approximately 1.4 cm and the EFS ranged between approximately 60 and approximately 300 cm(2), depending on the applicator type. Both measurements and simulations showed a split-up of the SAR focus with a 2 cm water bolus. The extent and location of air layers has a strong influence on the shape and size of the iso-SAR contours with a value higher than 50%, but the impact on EFS and EHD is limited. Simulations, confirmed by measurements, showed that the presence of air between the rubber and the electrodes changes the iso-SAR contours, but the impact on the EFS and EHD is limited.

  12. STRENGTH PERFORMANCE ASSESSMENT IN A SIMULATED MEN'S GYMNASTICS STILL RINGS CROSS

    Directory of Open Access Journals (Sweden)

    Jennifer K. Dunlavy

    2007-03-01

    Full Text Available Athletes in sports such as the gymnastics who perform the still rings cross position are disadvantaged due to a lack of objective and convenient measurement methods. The gymnastics "cross" is a held isometric strength position considered fundamental to all still rings athletes. The purpose of this investigation was to determine if two small force platforms (FPs placed on supports to simulate a cross position could demonstrate the fidelity necessary to differentiate between athletes who could perform a cross from those who could not. Ten gymnasts (5 USA Gymnastics, Senior National Team, and 5 Age Group Level Gymnasts agreed to participate. The five Senior National Team athletes were grouped as cross Performers; the Age Group Gymnasts could not successfully perform the cross position and were grouped as cross Non- Performers. The two small FPs were first tested for reliability and validity and were then used to obtain a force-time record of a simulated cross position. The simulated cross test consisted of standing between two small force platforms placed on top of large solid gymnastics spotting blocks. The gymnasts attempted to perform a cross position by placing their hands at the center of the FPs and pressing downward with sufficient force that they could remove the support of their feet from the floor. Force-time curves (100 Hz were obtained and analyzed for the sum of peak and mean arm ground reaction forces. The summed arm forces, mean and peak, were compared to body weight to determine how close the gymnasts came to achieving forces equal to body weight and thus the ability to perform the cross. The mean and peak summed arm forces were able to statistically differentiate between athletes who could perform the cross from those who could not (p < 0.05. The force-time curves and small FPs showed sufficient fidelity to differentiate between Performer and Non- Performer groups. This experiment showed that small and inexpensive force platforms

  13. Power converter topologies for wind energy conversion systems: Integrated modeling, control strategy and performance simulation

    Energy Technology Data Exchange (ETDEWEB)

    Melicio, R.; Catalao, J.P.S. [Department of Electromechanical Engineering, University of Beira Interior, R. Fonte do Lameiro, 6201-001 Covilha (Portugal); Mendes, V.M.F. [Department of Electrical Engineering and Automation, Instituto Superior de Engenharia de Lisboa, R. Conselheiro Emidio Navarro, 1950-062 Lisbon (Portugal)

    2010-10-15

    This paper presents new integrated model for variable-speed wind energy conversion systems, considering a more accurate dynamic of the wind turbine, rotor, generator, power converter and filter. Pulse width modulation by space vector modulation associated with sliding mode is used for controlling the power converters. Also, power factor control is introduced at the output of the power converters. Comprehensive performance simulation studies are carried out with matrix, two-level and multilevel power converter topologies in order to adequately assert the system performance. Conclusions are duly drawn. (author)

  14. The effect of klapskate hinge position on push-off performance: a simulation study

    OpenAIRE

    Houdijk, J.H.P.; Bobbert, M.F.; de Koning, J.J.; de Groot, G.

    2003-01-01

    Purpose: The introduction of the klapskate in speed skating confronts skaters with the question of how to adjust the position of the hinge in order to maximize performance. The purpose of this study was to reveal the constraint that klapskate hinge position imposes on push-off performance in speed skating. Method: For this purpose, a model of the musculoskeletal system was designed to simulate a simplified, two-dimensional skating push off. To capture the essence of a skating push off, this m...

  15. Measuring Human Performance in Simulated Nuclear Power Plant Control Rooms Using Eye Tracking

    Energy Technology Data Exchange (ETDEWEB)

    Kovesdi, Casey Robert [Idaho National Lab. (INL), Idaho Falls, ID (United States); Rice, Brandon Charles [Idaho National Lab. (INL), Idaho Falls, ID (United States); Bower, Gordon Ross [Idaho National Lab. (INL), Idaho Falls, ID (United States); Spielman, Zachary Alexander [Idaho National Lab. (INL), Idaho Falls, ID (United States); Hill, Rachael Ann [Idaho National Lab. (INL), Idaho Falls, ID (United States); LeBlanc, Katya Lee [Idaho National Lab. (INL), Idaho Falls, ID (United States)

    2015-11-01

    Control room modernization will be an important part of life extension for the existing light water reactor fleet. As part of modernization efforts, personnel will need to gain a full understanding of how control room technologies affect performance of human operators. Recent advances in technology enables the use of eye tracking technology to continuously measure an operator’s eye movement, which correlates with a variety of human performance constructs such as situation awareness and workload. This report describes eye tracking metrics in the context of how they will be used in nuclear power plant control room simulator studies.

  16. Measuring Human Performance in Simulated Nuclear Power Plant Control Rooms Using Eye Tracking

    International Nuclear Information System (INIS)

    Kovesdi, Casey Robert; Rice, Brandon Charles; Bower, Gordon Ross; Spielman, Zachary Alexander; Hill, Rachael Ann; LeBlanc, Katya Lee

    2015-01-01

    Control room modernization will be an important part of life extension for the existing light water reactor fleet. As part of modernization efforts, personnel will need to gain a full understanding of how control room technologies affect performance of human operators. Recent advances in technology enables the use of eye tracking technology to continuously measure an operator's eye movement, which correlates with a variety of human performance constructs such as situation awareness and workload. This report describes eye tracking metrics in the context of how they will be used in nuclear power plant control room simulator studies.

  17. Accurate simulation of MPPT methods performance when applied to commercial photovoltaic panels.

    Science.gov (United States)

    Cubas, Javier; Pindado, Santiago; Sanz-Andrés, Ángel

    2015-01-01

    A new, simple, and quick-calculation methodology to obtain a solar panel model, based on the manufacturers' datasheet, to perform MPPT simulations, is described. The method takes into account variations on the ambient conditions (sun irradiation and solar cells temperature) and allows fast MPPT methods comparison or their performance prediction when applied to a particular solar panel. The feasibility of the described methodology is checked with four different MPPT methods applied to a commercial solar panel, within a day, and under realistic ambient conditions.

  18. Accurate Simulation of MPPT Methods Performance When Applied to Commercial Photovoltaic Panels

    Directory of Open Access Journals (Sweden)

    Javier Cubas

    2015-01-01

    Full Text Available A new, simple, and quick-calculation methodology to obtain a solar panel model, based on the manufacturers’ datasheet, to perform MPPT simulations, is described. The method takes into account variations on the ambient conditions (sun irradiation and solar cells temperature and allows fast MPPT methods comparison or their performance prediction when applied to a particular solar panel. The feasibility of the described methodology is checked with four different MPPT methods applied to a commercial solar panel, within a day, and under realistic ambient conditions.

  19. High-Performance Modeling and Simulation of Anchoring in Granular Media for NEO Applications

    Science.gov (United States)

    Quadrelli, Marco B.; Jain, Abhinandan; Negrut, Dan; Mazhar, Hammad

    2012-01-01

    NASA is interested in designing a spacecraft capable of visiting a near-Earth object (NEO), performing experiments, and then returning safely. Certain periods of this mission would require the spacecraft to remain stationary relative to the NEO, in an environment characterized by very low gravity levels; such situations require an anchoring mechanism that is compact, easy to deploy, and upon mission completion, easy to remove. The design philosophy used in this task relies on the simulation capability of a high-performance multibody dynamics physics engine. On Earth, it is difficult to create low-gravity conditions, and testing in low-gravity environments, whether artificial or in space, can be costly and very difficult to achieve. Through simulation, the effect of gravity can be controlled with great accuracy, making it ideally suited to analyze the problem at hand. Using Chrono::Engine, a simulation pack age capable of utilizing massively parallel Graphic Processing Unit (GPU) hardware, several validation experiments were performed. Modeling of the regolith interaction has been carried out, after which the anchor penetration tests were performed and analyzed. The regolith was modeled by a granular medium composed of very large numbers of convex three-dimensional rigid bodies, subject to microgravity levels and interacting with each other with contact, friction, and cohesional forces. The multibody dynamics simulation approach used for simulating anchors penetrating a soil uses a differential variational inequality (DVI) methodology to solve the contact problem posed as a linear complementarity method (LCP). Implemented within a GPU processing environment, collision detection is greatly accelerated compared to traditional CPU (central processing unit)- based collision detection. Hence, systems of millions of particles interacting with complex dynamic systems can be efficiently analyzed, and design recommendations can be made in a much shorter time. The figure

  20. SU-F-T-50: Evaluation of Monte Carlo Simulations Performance for Pediatric Brachytherapy Dosimetry

    Energy Technology Data Exchange (ETDEWEB)

    Chatzipapas, C; Kagadis, G [University Patras, Rion, Ahaia (Greece); Papadimitroulas, P [BET Solutions, Athens, Attiki (Greece); Loudos, G [Technological Educational Institute of Athens, Egaleo, Attiki (Greece); Papanikolaou, N [University of Texas HSC SA, San Antonio, TX (United States)

    2016-06-15

    Purpose: Pediatric tumors are generally treated with multi-modal procedures. Brachytherapy can be used with pediatric tumors, especially given that in this patient population low toxicity on normal tissues is critical as is the suppression of the probability for late malignancies. Our goal is to validate the GATE toolkit on realistic brachytherapy applications, and evaluate brachytherapy plans on pediatrics for accurate dosimetry on sensitive and critical organs of interest. Methods: The GATE Monte Carlo (MC) toolkit was used. Two High Dose Rate (HDR) 192Ir brachytherapy sources were simulated (Nucletron mHDR-v1 and Varian VS2000), and fully validated using the AAPM and ESTRO protocols. A realistic brachytherapy plan was also simulated using the XCAT anthropomorphic computational model .The simulated data were compared to the clinical dose points. Finally, a 14 years old girl with vaginal rhabdomyosarcoma was modelled based on clinical procedures for the calculation of the absorbed dose per organ. Results: The MC simulations resulted in accurate dosimetry in terms of dose rate constant (Λ), radial dose gL(r) and anisotropy function F(r,θ) for both sources.The simulations were executed using ∼1010 number of primaries resulting in statistical uncertainties lower than 2%.The differences between the theoretical values and the simulated ones ranged from 0.01% up to 3.3%, with the largest discrepancy (6%) being observed in the dose rate constant calculation.The simulated DVH using an adult female XCAT model was also compared to a clinical one resulting in differences smaller than 5%. Finally, a realistic pediatric brachytherapy simulation was performed to evaluate the absorbed dose per organ and to calculate DVH with respect to heterogeneities of the human anatomy. Conclusion: GATE is a reliable tool for brachytherapy simulations both for source modeling and for dosimetry in anthropomorphic voxelized models. Our project aims to evaluate a variety of pediatric

  1. Effect of Advanced Trauma Life Support program on medical interns' performance in simulated trauma patient management.

    Science.gov (United States)

    Ahmadi, Koorosh; Sedaghat, Mohammad; Safdarian, Mahdi; Hashemian, Amir-Masoud; Nezamdoust, Zahra; Vaseie, Mohammad; Rahimi-Movaghar, Vafa

    2013-01-01

    Since appropriate and time-table methods in trauma care have an important impact on patients'outcome, we evaluated the effect of Advanced Trauma Life Support (ATLS) program on medical interns' performance in simulated trauma patient management. A descriptive and analytical study before and after the training was conducted on 24 randomly selected undergraduate medical interns from Imam Reza Hospital in Mashhad, Iran. On the first day, we assessed interns' clinical knowledge and their practical skill performance in confronting simulated trauma patients. After 2 days of ATLS training, we performed the same study and evaluated their score again on the fourth day. The two findings, pre- and post- ATLS periods, were compared through SPSS version 15.0 software. P values less than 0.05 were considered statistically significant. Our findings showed that interns'ability in all the three tasks improved after the training course. On the fourth day after training, there was a statistically significant increase in interns' clinical knowledge of ATLS procedures, the sequence of procedures and skill performance in trauma situations (P less than 0.001, P equal to 0.016 and P equal to 0.01 respectively). ATLS course has an important role in increasing clinical knowledge and practical skill performance of trauma care in medical interns.

  2. Computational performance of a smoothed particle hydrodynamics simulation for shared-memory parallel computing

    Science.gov (United States)

    Nishiura, Daisuke; Furuichi, Mikito; Sakaguchi, Hide

    2015-09-01

    The computational performance of a smoothed particle hydrodynamics (SPH) simulation is investigated for three types of current shared-memory parallel computer devices: many integrated core (MIC) processors, graphics processing units (GPUs), and multi-core CPUs. We are especially interested in efficient shared-memory allocation methods for each chipset, because the efficient data access patterns differ between compute unified device architecture (CUDA) programming for GPUs and OpenMP programming for MIC processors and multi-core CPUs. We first introduce several parallel implementation techniques for the SPH code, and then examine these on our target computer architectures to determine the most effective algorithms for each processor unit. In addition, we evaluate the effective computing performance and power efficiency of the SPH simulation on each architecture, as these are critical metrics for overall performance in a multi-device environment. In our benchmark test, the GPU is found to produce the best arithmetic performance as a standalone device unit, and gives the most efficient power consumption. The multi-core CPU obtains the most effective computing performance. The computational speed of the MIC processor on Xeon Phi approached that of two Xeon CPUs. This indicates that using MICs is an attractive choice for existing SPH codes on multi-core CPUs parallelized by OpenMP, as it gains computational acceleration without the need for significant changes to the source code.

  3. Milking performance evaluation and factors affecting milking claw vacuum levels with flow simulator.

    Science.gov (United States)

    Enokidani, Masafumi; Kawai, Kazuhiro; Shinozuka, Yasunori; Watanabe, Aiko

    2017-08-01

    Milking performance of milking machines that matches the production capability of dairy cows is important in reducing the risk of mastitis, particularly in high-producing cows. This study used a simulated milking device to examine the milking performance of the milking system of 73 dairy farms and to analyze the factors affecting claw vacuum. Mean claw vacuum and range of fluctuation of claw vacuum (claw vacuum range) were measured at three different flow rates: 5.7, 7.6 and 8.7 kg/min. At the highest flow rate, only 16 farms (21.9%) met both standards of mean claw vacuum ≥35 kPa and claw vacuum range ≤ 7 kPa, showing that milking systems currently have poor milking performance. The factors affecting mean claw vacuum were claw type, milk-meter and vacuum shut-off device; the factor affecting claw vacuum range was claw type. Examination of the milking performance of the milking system using a simulated milking device allows an examination of the performance that can cope with high producing cows, indicating the possibility of reducing the risk of mastitis caused by inappropriate claw vacuum. © 2016 Japanese Society of Animal Science.

  4. Weather model performance on extreme rainfall events simulation's over Western Iberian Peninsula

    Science.gov (United States)

    Pereira, S. C.; Carvalho, A. C.; Ferreira, J.; Nunes, J. P.; Kaiser, J. J.; Rocha, A.

    2012-08-01

    This study evaluates the performance of the WRF-ARW numerical weather model in simulating the spatial and temporal patterns of an extreme rainfall period over a complex orographic region in north-central Portugal. The analysis was performed for the December month of 2009, during the Portugal Mainland rainy season. The heavy rainfall to extreme heavy rainfall periods were due to several low surface pressure's systems associated with frontal surfaces. The total amount of precipitation for December exceeded, in average, the climatological mean for the 1971-2000 time period in +89 mm, varying from 190 mm (south part of the country) to 1175 mm (north part of the country). Three model runs were conducted to assess possible improvements in model performance: (1) the WRF-ARW is forced with the initial fields from a global domain model (RunRef); (2) data assimilation for a specific location (RunObsN) is included; (3) nudging is used to adjust the analysis field (RunGridN). Model performance was evaluated against an observed hourly precipitation dataset of 15 rainfall stations using several statistical parameters. The WRF-ARW model reproduced well the temporal rainfall patterns but tended to overestimate precipitation amounts. The RunGridN simulation provided the best results but model performance of the other two runs was good too, so that the selected extreme rainfall episode was successfully reproduced.

  5. The effect of carbohydrate ingestion on performance during a simulated soccer match.

    Science.gov (United States)

    Goedecke, Julia H; White, Nicholas J; Chicktay, Waheed; Mahomed, Hafsa; Durandt, Justin; Lambert, Michael I

    2013-12-16

    This study investigated how performance was affected after soccer players, in a postprandial state, ingested a 7% carbohydrate (CHO) solution compared to a placebo (0% CHO) during a simulated soccer match. Using a double-blind placebo-controlled design, 22 trained male league soccer players (age: 24 ± 7 years, wt: 73.4 ± 12.0 kg, VO2max: 51.8 ± 4.3 mL O2/kg/min) completed two trials, separated by 7 days, during which they ingested, in random order, 700 mL of either a 7% CHO or placebo drink during a simulated soccer match. Ratings of perceived exertion (RPE), agility, timed and run to fatigue were measured during the trials. Change in agility times was not altered by CHO vs. placebo ingestion (0.57 ± 1.48 vs. 0.66 ± 1.00, p = 0.81). Timed runs to fatigue were 381 ± 267 s vs. 294 ± 159 s for the CHO and placebo drinks, respectively (p = 0.11). Body mass modified the relationship between time to fatigue and drink ingestion (p = 0.02 for drink × body mass), such that lower body mass was associated with increased time to fatigue when the players ingested CHO, but not placebo. RPE values for the final stage of the simulated soccer match were 8.5 ± 1.7 and 8.6 ± 1.5 for the CHO and placebo drinks respectively (p = 0.87). The group data showed that the 7% CHO solution (49 g CHO) did not significantly improve performance during a simulated soccer match in league soccer players who had normal pre-match nutrition. However, when adjusting for body mass, increasing CHO intake was associated with improved time to fatigue during the simulated soccer match.

  6. The Effect of Carbohydrate Ingestion on Performance during a Simulated Soccer Match

    Directory of Open Access Journals (Sweden)

    Julia H. Goedecke

    2013-12-01

    Full Text Available Aim: This study investigated how performance was affected after soccer players, in a postprandial state, ingested a 7% carbohydrate (CHO solution compared to a placebo (0% CHO during a simulated soccer match. Methods: Using a double-blind placebo-controlled design, 22 trained male league soccer players (age: 24 ± 7 years, wt: 73.4 ± 12.0 kg, VO2max: 51.8 ± 4.3 mL O2/kg/min completed two trials, separated by 7 days, during which they ingested, in random order, 700 mL of either a 7% CHO or placebo drink during a simulated soccer match. Ratings of perceived exertion (RPE, agility, timed and run to fatigue were measured during the trials. Results: Change in agility times was not altered by CHO vs. placebo ingestion (0.57 ± 1.48 vs. 0.66 ± 1.00, p = 0.81. Timed runs to fatigue were 381 ± 267 s vs. 294 ± 159 s for the CHO and placebo drinks, respectively (p = 0.11. Body mass modified the relationship between time to fatigue and drink ingestion (p = 0.02 for drink × body mass, such that lower body mass was associated with increased time to fatigue when the players ingested CHO, but not placebo. RPE values for the final stage of the simulated soccer match were 8.5 ± 1.7 and 8.6 ± 1.5 for the CHO and placebo drinks respectively (p = 0.87. Conclusions: The group data showed that the 7% CHO solution (49 g CHO did not significantly improve performance during a simulated soccer match in league soccer players who had normal pre-match nutrition. However, when adjusting for body mass, increasing CHO intake was associated with improved time to fatigue during the simulated soccer match.

  7. Direct numerical simulation of reactor two-phase flows enabled by high-performance computing

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Jun; Cambareri, Joseph J.; Brown, Cameron S.; Feng, Jinyong; Gouws, Andre; Li, Mengnan; Bolotnov, Igor A.

    2018-04-01

    Nuclear reactor two-phase flows remain a great engineering challenge, where the high-resolution two-phase flow database which can inform practical model development is still sparse due to the extreme reactor operation conditions and measurement difficulties. Owing to the rapid growth of computing power, the direct numerical simulation (DNS) is enjoying a renewed interest in investigating the related flow problems. A combination between DNS and an interface tracking method can provide a unique opportunity to study two-phase flows based on first principles calculations. More importantly, state-of-the-art high-performance computing (HPC) facilities are helping unlock this great potential. This paper reviews the recent research progress of two-phase flow DNS related to reactor applications. The progress in large-scale bubbly flow DNS has been focused not only on the sheer size of those simulations in terms of resolved Reynolds number, but also on the associated advanced modeling and analysis techniques. Specifically, the current areas of active research include modeling of sub-cooled boiling, bubble coalescence, as well as the advanced post-processing toolkit for bubbly flow simulations in reactor geometries. A novel bubble tracking method has been developed to track the evolution of bubbles in two-phase bubbly flow. Also, spectral analysis of DNS database in different geometries has been performed to investigate the modulation of the energy spectrum slope due to bubble-induced turbulence. In addition, the single-and two-phase analysis results are presented for turbulent flows within the pressurized water reactor (PWR) core geometries. The related simulations are possible to carry out only with the world leading HPC platforms. These simulations are allowing more complex turbulence model development and validation for use in 3D multiphase computational fluid dynamics (M-CFD) codes.

  8. Sodium bicarbonate ingestion increases glycolytic contribution and improves performance during simulated taekwondo combat.

    Science.gov (United States)

    Lopes-Silva, João Paulo; Da Silva Santos, Jonatas Ferreira; Artioli, Guilherme Giannini; Loturco, Irineu; Abbiss, Chris; Franchini, Emerson

    2018-04-01

    To investigate the effect of sodium bicarbonate (NaHCO 3 ) on performance and estimated energy system contribution during simulated taekwondo combat. Nine taekwondo athletes completed two experimental sessions separated by at least 48 h. Athletes consumed 300 mg/kg body mass of NaHCO 3 or placebo (CaCO 3 ) 90 min before the combat simulation (three rounds of 2 min separated by 1 min passive recovery), in a double-blind, randomized, repeated-measures crossover design. All simulated combat was filmed to quantify the time spent fighting in each round. Lactate concentration [La - ] and rating of perceived exertion (RPE) were measured before and after each round, whereas heart rate (HR) and the estimated contribution of the oxidative (W OXI ), ATP (adenosine triphosphate)-phosphocreatine (PCr) (W PCR ), and glycolytic (W [ La - ] ) systems were calculated during the combat simulation. [La - ] increased significantly after NaHCO 3 ingestion, when compared with the placebo condition (+14%, P = 0.04, d = 3.70). NaHCO 3 ingestion resulted in greater estimated glycolytic energy contribution in the first round when compared with the placebo condition (+31%, P = 0.01, d = 3.48). Total attack time was significantly greater after NaHCO 3 when compared with placebo (+13%, P = 0.05, d = 1.15). W OXI , W PCR , VO 2 , HR and RPE were not different between conditions (P > 0.05). NaHCO 3 ingestion was able to increase the contribution of glycolytic metabolism and, therefore, improve performance during simulated taekwondo combat.

  9. Simulated Performance Evaluation of a Selective Tracker Through Random Scenario Generation

    DEFF Research Database (Denmark)

    Hussain, Dil Muhammad Akbar

    2006-01-01

    performance assessment. Therefore, a random target motion scenario is adopted. Its implementation in particular for testing the proposed selective track splitting algorithm using Kalman filters is investigated through a number of performance parameters which gives the activity profile of the tracking scenario......  The paper presents a simulation study on the performance of a target tracker using selective track splitting filter algorithm through a random scenario implemented on a digital signal processor.  In a typical track splitting filter all the observation which fall inside a likelihood ellipse...... are used for update, however, in our proposed selective track splitting filter less number of observations are used for track update.  Much of the previous performance work [1] has been done on specific (deterministic) scenarios. One of the reasons for considering the specific scenarios, which were...

  10. Sodium bicarbonate supplementation prevents skilled tennis performance decline after a simulated match

    Directory of Open Access Journals (Sweden)

    Huang Ming-Hsiang

    2010-10-01

    Full Text Available Abstract The supplementation of sodium bicarbonate (NaHCO3 could increase performance or delay fatigue in intermittent high-intensity exercise. Prolonged tennis matches result in fatigue, which impairs skilled performance. The aim of this study was to investigate the effect of NaHCO3 supplementation on skilled tennis performance after a simulated match. Nine male college tennis players were recruited for this randomized cross-over, placebo-controlled, double-blind study. The participants consumed NaHCO3 (0.3 g. kg-1 or NaCl (0.209 g. kg-1 before the trial. An additional supplementation of 0.1 g. kg-1 NaHCO3 or 0.07 g. kg-1 NaCl was ingested after the third game in the simulated match. The Loughborough Tennis Skill Test was performed before and after the simulated match. Post-match [HCO3-] and base excess were significantly higher in the bicarbonate trial than those in the placebo trial. Blood [lactate] was significantly increased in the placebo (pre: 1.22 ± 0.54; post: 2.17 ± 1.46 mM and bicarbonate (pre: 1.23 ± 0.41; post: 3.21 ± 1.89 mM trials. The match-induced change in blood [lactate] was significantly higher in the bicarbonate trial. Blood pH remained unchanged in the placebo trial (pre: 7.37 ± 0.32; post: 7.37 ± 0.14 but was significantly increased in the bicarbonate trial (pre: 7.37 ± 0.26; post: 7.45 ± 0.63, indicating a more alkaline environment. The service and forehand ground stroke consistency scores were declined significantly after the simulated match in the placebo trial, while they were maintained in the bicarbonate trial. The match-induced declines in the consistency scores were significantly larger in the placebo trial than those in the bicarbonate trial. This study suggested that NaHCO3 supplementation could prevent the decline in skilled tennis performance after a simulated match.

  11. Internal Flow Simulation of Enhanced Performance Solid Rocket Booster for the Space Transportation System

    Science.gov (United States)

    Ahmad, Rashid A.; McCool, Alex (Technical Monitor)

    2001-01-01

    An enhanced performance solid rocket booster concept for the space shuttle system has been proposed. The concept booster will have strong commonality with the existing, proven, reliable four-segment Space Shuttle Reusable Solid Rocket Motors (RSRM) with individual component design (nozzle, insulator, etc.) optimized for a five-segment configuration. Increased performance is desirable to further enhance safety/reliability and/or increase payload capability. Performance increase will be achieved by adding a fifth propellant segment to the current four-segment booster and opening the throat to accommodate the increased mass flow while maintaining current pressure levels. One development concept under consideration is the static test of a "standard" RSRM with a fifth propellant segment inserted and appropriate minimum motor modifications. Feasibility studies are being conducted to assess the potential for any significant departure in component performance/loading from the well-characterized RSRM. An area of concern is the aft motor (submerged nozzle inlet, aft dome, etc.) where the altered internal flow resulting from the performance enhancing features (25% increase in mass flow rate, higher Mach numbers, modified subsonic nozzle contour) may result in increased component erosion and char. To assess this issue and to define the minimum design changes required to successfully static test a fifth segment RSRM engineering test motor, internal flow studies have been initiated. Internal aero-thermal environments were quantified in terms of conventional convective heating and discrete phase alumina particle impact/concentration and accretion calculations via Computational Fluid Dynamics (CFD) simulation. Two sets of comparative CFD simulations of the RSRM and the five-segment (IBM) concept motor were conducted with CFD commercial code FLUENT. The first simulation involved a two-dimensional axi-symmetric model of the full motor, initial grain RSRM. The second set of analyses

  12. Assessment of driving-related performance in chronic whiplash using an advanced driving simulator.

    Science.gov (United States)

    Takasaki, Hiroshi; Treleaven, Julia; Johnston, Venerina; Rakotonirainy, Andry; Haines, Andrew; Jull, Gwendolen

    2013-11-01

    Driving is often nominated as problematic by individuals with chronic whiplash associated disorders (WAD), yet driving-related performance has not been evaluated objectively. The purpose of this study was to test driving-related performance in persons with chronic WAD against healthy controls of similar age, gender and driving experience to determine if driving-related performance in the WAD group was sufficiently impaired to recommend fitness to drive assessment. Driving-related performance was assessed using an advanced driving simulator during three driving scenarios; freeway, residential and a central business district (CBD). Total driving duration was approximately 15min. Five driving tasks which could cause a collision (critical events) were included in the scenarios. In addition, the effect of divided attention (identify red dots projected onto side or rear view mirrors) was assessed three times in each scenario. Driving performance was measured using the simulator performance index (SPI) which is calculated from 12 measures. z-Scores for all SPI measures were calculated for each WAD subject based on mean values of the control subjects. The z-scores were then averaged for the WAD group. A z-score of ≤-2 indicated a driving failing grade in the simulator. The number of collisions over the five critical events was compared between the WAD and control groups as was reaction time and missed response ratio in identifying the red dots. Seventeen WAD and 26 control subjects commenced the driving assessment. Demographic data were comparable between the groups. All subjects completed the freeway scenario but four withdrew during the residential and eight during the CBD scenario because of motion sickness. All scenarios were completed by 14 WAD and 17 control subjects. Mean z-scores for the SPI over the three scenarios was statistically lower in the WAD group (-0.3±0.3; Pdriving. There were no differences in the reaction time and missed response ratio in divided

  13. Simulation Analysis as a Way to Assess the Performance of Important Unit Root and Change in Persistence Tests

    DEFF Research Database (Denmark)

    Fernández, Raúl O.; Vera-Valdés, J. Eduardo

    2013-01-01

    This chapter shows a way to, using simulation analysis, assess the performance of some of the most popular unit root and change in persistence tests. The authors do this by means of Monte Carlo simulations. The findings suggest that these tests show a lower than expected performance when dealing ...

  14. Particle–Mixing Simulations Using DEM and Comparison of the Performance of Mixing Indices

    International Nuclear Information System (INIS)

    Cho, Migyung

    2017-01-01

    Mixing of molecular grains having different characteristics is very important in many industries such as the food and pharmaceutical industries. With the development of computer simulations, it is common practice to find the optimal mixing conditions through a simulation before the actual mixing task to estimate the proper level of mixing. Accordingly, there has been an increasing need for a mixing index to measure the mix of particles in the simulation process. Mixing indices, which have been widely used so far, can largely be classified into two types: first is the statistical-based mixing index, which is prepared using the sampling method, and the second is the mixing index that is prepared using all the particles. In this paper, we calculated mixing indices in different ways for the data in the course of mixing the particles using the DEM simulation. Additionally, we compared the performance, advantages, and disadvantages of each mixing index. Therefore, I propose a standard that can be used to select an appropriate mixing index.

  15. Particle–Mixing Simulations Using DEM and Comparison of the Performance of Mixing Indices

    Energy Technology Data Exchange (ETDEWEB)

    Cho, Migyung [Tongmyong Univ., Busan (Korea, Republic of)

    2017-02-15

    Mixing of molecular grains having different characteristics is very important in many industries such as the food and pharmaceutical industries. With the development of computer simulations, it is common practice to find the optimal mixing conditions through a simulation before the actual mixing task to estimate the proper level of mixing. Accordingly, there has been an increasing need for a mixing index to measure the mix of particles in the simulation process. Mixing indices, which have been widely used so far, can largely be classified into two types: first is the statistical-based mixing index, which is prepared using the sampling method, and the second is the mixing index that is prepared using all the particles. In this paper, we calculated mixing indices in different ways for the data in the course of mixing the particles using the DEM simulation. Additionally, we compared the performance, advantages, and disadvantages of each mixing index. Therefore, I propose a standard that can be used to select an appropriate mixing index.

  16. H5Part A Portable High Performance Parallel Data Interface for Particle Simulations

    CERN Document Server

    Adelmann, Andreas; Shalf, John M; Siegerist, Cristina

    2005-01-01

    Largest parallel particle simulations, in six dimensional phase space generate wast amont of data. It is also desirable to share data and data analysis tools such as ParViT (Particle Visualization Toolkit) among other groups who are working on particle-based accelerator simulations. We define a very simple file schema built on top of HDF5 (Hierarchical Data Format version 5) as well as an API that simplifies the reading/writing of the data to the HDF5 file format. HDF5 offers a self-describing machine-independent binary file format that supports scalable parallel I/O performance for MPI codes on a variety of supercomputing systems and works equally well on laptop computers. The API is available for C, C++, and Fortran codes. The file format will enable disparate research groups with very different simulation implementations to share data transparently and share data analysis tools. For instance, the common file format will enable groups that depend on completely different simulation implementations to share c...

  17. Performance curves of room air conditioners for building energy simulation tools

    International Nuclear Information System (INIS)

    Meissner, José W.; Abadie, Marc O.; Moura, Luís M.; Mendonça, Kátia C.; Mendes, Nathan

    2014-01-01

    Highlights: • Experimental characteristic curves for two room air conditioners are presented. • These results can be implemented in building simulation codes. • The energy consumption under different conditions can numerically determine. • The labeled higher energy efficiency product not always provides the best result. - Abstract: In order to improve the modeling of air conditioners in building simulation tools, the characteristic curves for total cooling capacity, sensible cooling capacity and energy efficiency ratio of two room units were determined. They were obtained by means of standard capacity tests on climatic chambers in a set of environmental conditions described by external dry- and internal wet bulb temperatures. Afterward, the performance of these two units and that of four other units, with and without taking into to account the thermodynamic variations of the surrounding environments on it, were compared using a whole building simulation program for simulating a conditioned space. The comparative analysis showed that the air conditioner with the higher energy efficiency rating not always provides the lowest power consumption in real conditions of use

  18. Proving test on the performance of a Multiple-Excitation Simulator

    International Nuclear Information System (INIS)

    Fujita, Katsuhisa; Ito, Tomohiro; Kojima, Nobuyuki; Sasaki, Yoichi; Abe, Hiroshi; Kuroda, Katsuhiko

    1995-01-01

    Seismic excitation test on large scale piping systems is scheduled to be carried out by the Nuclear power Engineering Corporation (NUPEC) using the large-scale, high-performance vibration table at the Tadotsu Engineering Laboratory, under the sponsorship of the Ministry of International Trade and Industry (MITI). In the test, the piping systems simulate the main steam piping system and the main feed water piping system in the nuclear power plants. In this study, a fundamental test was carried out to prove the performance of the Multiple Excitation Simulator which consists of the hydraulic actuator and the control system. An L-shaped piping system and a hydraulic actuator were installed on the shaking table. Acceleration and displacement generated by the actuator were measured. The performance of the actuator and the control system was discussed comparing the measured values and the target values on the time histories and the response spectrum of the acceleration. As a result, it was proved that the actuator and the control system have good performance and will be applicable to the verification test

  19. Simulator Evaluation of Drivers’ Performance on Rural Highways in relation to Drivers’ Visual Attention Demands

    Directory of Open Access Journals (Sweden)

    Yaqin Qin

    2015-01-01

    Full Text Available Aim of the study is to investigate, by means of a driving simulator experiment, drivers’ performance in terms of lateral position, speed, deceleration, steering angle, and breaking times on a divided two-lane rural highway in relation to drivers’ visual attention (VD. In the experiment, the virtual scene of twenty different geometric alignment sections without traffic and the VD testing were designed. Twenty-three experienced drivers with the calibration of attention capacity participated in a 30 km drive in an interactive fixed-base simulator. Each participant was required to drive with the controlled speed of 60 km/h along the central lane as repeating random number and was evaluated on VD and driving performances. Three different data analysis techniques were used: (a statistical tests and hypothesis test of curvature change rate (CCR of the geometric alignments, visual attention demands, and driving performance data, (b correlation analysis of VD, CCRs, and driving behaviors, and (c regression analysis of the VD and CCRs. Results have showed that the driving performance can be effectively influenced by the highway alignment and a prediction model built in this study can evaluate the drivers’ visual attention demands before the highway constructed. The interactions among VD, driving behavior, and CCRs were also found.

  20. Three-dimensional simulations in optimal performance trial between two types of Hall sensors fabrication technologies

    Energy Technology Data Exchange (ETDEWEB)

    Paun, Maria-Alexandra, E-mail: map65@cam.ac.uk

    2015-10-01

    The main objective of the present work is to make a comparison between Hall devices integrated in regular bulk and Silicon-on-Insulator (SOI) CMOS technology. A three-dimensional model based on numerical estimation is provided for a particular XL Hall structure in two different technologies (the first one is XFAB XH 0.35 µm regular bulk CMOS and the second one is XFAB SOI XI10 1 µm non-fully depleted). In assessing the performance of the Hall Effect sensors included in the comparison, both three-dimensional physical simulations and measurements results will be used. In order to discriminate which category of sensors has the highest performance, their main characteristic parameters, including input resistance, Hall voltage, absolute sensitivity and their temperature drift, will be extracted and compared. Electrostatic potential and current density distribution are important aspects that are also investigated. The particular technology offering the highest sensor performance is identified. - Highlights: • A comparison between Hall devices integrated in regular bulk and SOI CMOS technologies is made. • A three-dimensional model for the XL Hall structure, in the two technologies, is provided. • The main characteristic parameters and the temperature drift are investigated. • The sensors performance is evaluated using 3D physical simulations and measurements data.

  1. Human performance across decision making, selective attention, and working memory tasks: Experimental data and computer simulations

    Directory of Open Access Journals (Sweden)

    Andrea Stocco

    2018-04-01

    Full Text Available This article describes the data analyzed in the paper “Individual differences in the Simon effect are underpinned by differences in the competitive dynamics in the basal ganglia: An experimental verification and a computational model” (Stocco et al., 2017 [1]. The data includes behavioral results from participants performing three cognitive tasks (Probabilistic Stimulus Selection (Frank et al., 2004 [2], Simon task (Craft and Simon, 1970 [3], and Automated Operation Span (Unsworth et al., 2005 [4], as well as simulationed traces generated by a computational neurocognitive model that accounts for individual variations in human performance across the tasks. The experimental data encompasses individual data files (in both preprocessed and native output format as well as group-level summary files. The simulation data includes the entire model code, the results of a full-grid search of the model's parameter space, and the code used to partition the model space and parallelize the simulations. Finally, the repository includes the R scripts used to carry out the statistical analyses reported in the original paper.

  2. Human performance across decision making, selective attention, and working memory tasks: Experimental data and computer simulations.

    Science.gov (United States)

    Stocco, Andrea; Yamasaki, Brianna L; Prat, Chantel S

    2018-04-01

    This article describes the data analyzed in the paper "Individual differences in the Simon effect are underpinned by differences in the competitive dynamics in the basal ganglia: An experimental verification and a computational model" (Stocco et al., 2017) [1]. The data includes behavioral results from participants performing three cognitive tasks (Probabilistic Stimulus Selection (Frank et al., 2004) [2], Simon task (Craft and Simon, 1970) [3], and Automated Operation Span (Unsworth et al., 2005) [4]), as well as simulationed traces generated by a computational neurocognitive model that accounts for individual variations in human performance across the tasks. The experimental data encompasses individual data files (in both preprocessed and native output format) as well as group-level summary files. The simulation data includes the entire model code, the results of a full-grid search of the model's parameter space, and the code used to partition the model space and parallelize the simulations. Finally, the repository includes the R scripts used to carry out the statistical analyses reported in the original paper.

  3. Science-Based Simulation Model of Human Performance for Human Reliability Analysis

    International Nuclear Information System (INIS)

    Kelly, Dana L.; Boring, Ronald L.; Mosleh, Ali; Smidts, Carol

    2011-01-01

    Human reliability analysis (HRA), a component of an integrated probabilistic risk assessment (PRA), is the means by which the human contribution to risk is assessed, both qualitatively and quantitatively. However, among the literally dozens of HRA methods that have been developed, most cannot fully model and quantify the types of errors that occurred at Three Mile Island. Furthermore, all of the methods lack a solid empirical basis, relying heavily on expert judgment or empirical results derived in non-reactor domains. Finally, all of the methods are essentially static, and are thus unable to capture the dynamics of an accident in progress. The objective of this work is to begin exploring a dynamic simulation approach to HRA, one whose models have a basis in psychological theories of human performance, and whose quantitative estimates have an empirical basis. This paper highlights a plan to formalize collaboration among the Idaho National Laboratory (INL), the University of Maryland, and The Ohio State University (OSU) to continue development of a simulation model initially formulated at the University of Maryland. Initial work will focus on enhancing the underlying human performance models with the most recent psychological research, and on planning follow-on studies to establish an empirical basis for the model, based on simulator experiments to be carried out at the INL and at the OSU.

  4. Impact of simulation training on Jordanian nurses' performance of basic life support skills: A pilot study.

    Science.gov (United States)

    Toubasi, Samar; Alosta, Mohammed R; Darawad, Muhammad W; Demeh, Waddah

    2015-09-01

    Providing efficient basic life support (BLS) training is crucial for practicing nurses who provide direct patient care. Nevertheless, data addressing the impact of BLS courses on the skills and performance of Jordanian nurses are scarce. This study aimed to assess the effectiveness of a BLS simulation training on Jordanian nurses' skill improvement in cardiopulmonary resuscitation. A prospective quasi-experimental, single group pretest-posttest design was used to study the effect of BLS simulation; using a 9-item checklist; on the spot training; American Heart Association, on a group of Jordanian nurses. A pre-test was conducted following a CPR scenario to test the skills using 9-item checklist extrapolated from the American Heart Association guidelines. After debriefing, an interactive on spot training was provided. Later, participants undertook an unscheduled post-test after four weeks that included the same nine items. Thirty registered nurses with a mean clinical experience of 6.1years participated in the study. Comparing pre-test (M=4.6, SD=2.9, range=0 to 9) with post-test results (M=7.5, SD=1.7, range=4 to 9) showed an overall improvement in skills and BLS scores after the simulation training program (t=7.4, df=29, pskills and performance among Jordanian nurses. A refreshment BLS training session for nurses is highly recommended to guarantee nurses' preparedness in actual CPR scenarios. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. A system dynamics-based environmental performance simulation of construction waste reduction management in China.

    Science.gov (United States)

    Ding, Zhikun; Yi, Guizhen; Tam, Vivian W Y; Huang, Tengyue

    2016-05-01

    A huge amount of construction waste has been generated from increasingly higher number of construction activities than in the past, which has significant negative impacts on the environment if they are not properly managed. Therefore, effective construction waste management is of primary importance for future sustainable development. Based on the theory of planned behaviors, this paper develops a system dynamic model of construction waste reduction management at the construction phase to simulate the environmental benefits of construction waste reduction management. The application of the proposed model is shown using a case study in Shenzhen, China. Vensim is applied to simulate and analyze the model. The simulation results indicate that source reduction is an effective waste reduction measure which can reduce 27.05% of the total waste generation. Sorting behaviors are a premise for improving the construction waste recycling and reuse rates which account for 15.49% of the total waste generated. The environmental benefits of source reduction outweigh those of sorting behaviors. Therefore, to achieve better environmental performance of the construction waste reduction management, attention should be paid to source reduction such as low waste technologies and on-site management performance. In the meantime, sorting behaviors encouragement such as improving stakeholders' waste awareness, refining regulations, strengthening government supervision and controlling illegal dumping should be emphasized. Copyright © 2016 Elsevier Ltd. All rights reserved.

  6. Synthetic and Enhanced Vision Systems for NextGen (SEVS) Simulation and Flight Test Performance Evaluation

    Science.gov (United States)

    Shelton, Kevin J.; Kramer, Lynda J.; Ellis,Kyle K.; Rehfeld, Sherri A.

    2012-01-01

    The Synthetic and Enhanced Vision Systems for NextGen (SEVS) simulation and flight tests are jointly sponsored by NASA's Aviation Safety Program, Vehicle Systems Safety Technology project and the Federal Aviation Administration (FAA). The flight tests were conducted by a team of Honeywell, Gulfstream Aerospace Corporation and NASA personnel with the goal of obtaining pilot-in-the-loop test data for flight validation, verification, and demonstration of selected SEVS operational and system-level performance capabilities. Nine test flights (38 flight hours) were conducted over the summer and fall of 2011. The evaluations were flown in Gulfstream.s G450 flight test aircraft outfitted with the SEVS technology under very low visibility instrument meteorological conditions. Evaluation pilots flew 108 approaches in low visibility weather conditions (600 ft to 2400 ft visibility) into various airports from Louisiana to Maine. In-situ flight performance and subjective workload and acceptability data were collected in collaboration with ground simulation studies at LaRC.s Research Flight Deck simulator.

  7. Comparative performance of different stochastic methods to simulate drug exposure and variability in a population.

    Science.gov (United States)

    Tam, Vincent H; Kabbara, Samer

    2006-10-01

    Monte Carlo simulations (MCSs) are increasingly being used to predict the pharmacokinetic variability of antimicrobials in a population. However, various MCS approaches may differ in the accuracy of the predictions. We compared the performance of 3 different MCS approaches using a data set with known parameter values and dispersion. Ten concentration-time profiles were randomly generated and used to determine the best-fit parameter estimates. Three MCS methods were subsequently used to simulate the AUC(0-infinity) of the population, using the central tendency and dispersion of the following in the subject sample: 1) K and V; 2) clearance and V; 3) AUC(0-infinity). In each scenario, 10000 subject simulations were performed. Compared to true AUC(0-infinity) of the population, mean biases by various methods were 1) 58.4, 2) 380.7, and 3) 12.5 mg h L(-1), respectively. Our results suggest that the most realistic MCS approach appeared to be based on the variability of AUC(0-infinity) in the subject sample.

  8. Annual Performance Assessment of Complex Fenestration Systems in Sunny Climates Using Advanced Computer Simulations

    Directory of Open Access Journals (Sweden)

    Chantal Basurto

    2015-12-01

    Full Text Available Complex Fenestration Systems (CFS are advanced daylighting systems that are placed on the upper part of a window to improve the indoor daylight distribution within rooms. Due to their double function of daylight redirection and solar protection, they are considered as a solution to mitigate the unfavorable effects due to the admission of direct sunlight in buildings located in prevailing sunny climates (risk of glare and overheating. Accordingly, an adequate assessment of their performance should include an annual evaluation of the main aspects relevant to the use of daylight in such regions: the indoor illuminance distribution, thermal comfort, and visual comfort of the occupant’s. Such evaluation is possible with the use of computer simulations combined with the bi-directional scattering distribution function (BSDF data of these systems. This study explores the use of available methods to assess the visible and thermal annual performance of five different CFS using advanced computer simulations. To achieve results, an on-site daylight monitoring was carried out in a building located in a predominantly sunny climate location, and the collected data was used to create and calibrate a virtual model used to carry-out the simulations. The results can be employed to select the CFS, which improves visual and thermal interior environment for the occupants.

  9. Performance of an alpha-vane and pitot tube in simulated heavy rain environment

    Science.gov (United States)

    Luers, J. K.; Fiscus, I. B.

    1985-01-01

    Experimental tests were conducted in the UDRI Environmental Wind/Rain Tunnel to establish the performance of an alpha-vane, that measures angle of attack, in a simulated heavy rain environment. The tests consisted of emersing the alpha-vane in an airstream with a concurrent water spray penetrating vertically through the airstream. The direction of the spray was varied to make an angle of 5.8 to 18 deg with the airstream direction in order to simulate the conditions that occur when an aircraft lands in a heavy rain environment. Rainrates simulated varied from 1000 to 1200 mm/hr which are the most severe ever expected to be encountered by an aircraft over even a 30 second period. Tunnel airspeeds ranged from 85 to 125 miles per hour. The results showed that even the most severe rainrates produced a misalignment in the alpha-vane of only 1 deg away from the airstream direction. Thus for normal rain conditions experienced by landing aircraft no significant deterioration in alpha-vane performance is expected.

  10. Effect of carbohydrate or sodium bicarbonate ingestion on performance during a validated basketball simulation test.

    Science.gov (United States)

    Afman, Gregg; Garside, Richard M; Dinan, Neal; Gant, Nicholas; Betts, James A; Williams, Clyde

    2014-12-01

    Current recommendations for nutritional interventions in basketball are largely extrapolated from laboratory-based studies that are not sport-specific. We therefore adapted and validated a basketball simulation test relative to competitive basketball games using well-trained basketball players (n = 10), then employed this test to evaluate the effects of two common preexercise nutritional interventions on basketball-specific physical and skilled performance. Specifically, in a randomized and counterbalanced order, participants ingested solutions providing either 75 g carbohydrate (sucrose) 45 min before exercise (Study A; n = 10) or 2 × 0.2 g · kg(-1) sodium bicarbonate (NaHCO3) 90 and 20 min before exercise (Study B; n = 7), each relative to appropriate placebos (H2O and 2 × 0.14 g · kg(-1) NaCl, respectively). Heart rate, sweat rate, pedometer count, and perceived exertion did not systematically differ between the 60-min basketball simulation test and competitive basketball, with a strong positive correlation in heart rate response (r = .9, p basketball simulation test provides a valid reflection of physiological demands in competitive basketball and is sufficiently sensitive to detect meaningful changes in physical and skilled performance. While there are benefits of preexercise carbohydrate or sodium bicarbonate ingestion, these should be balanced against potential negative side effects.

  11. The performance of Dräger Oxylog ventilators at simulated altitude.

    Science.gov (United States)

    Flynn, J G; Singh, B

    2008-07-01

    Ventilated patients frequently require transport by air in a hypobaric environment. Previous studies have demonstrated significant changes in the performance of ventilators with changes in cabin pressure (altitude) but no studies have been published on the function of modem ventilators at altitude. This experiment set out to evaluate ventilatory parameters (tidal volume and respiratory rate) of three commonly used transport ventilators (the Dräger Oxylog 1000, 2000 and 3000) in a simulated hypobaric environment. Ventilators were assessed using either air-mix (60% oxygen) or 100% oxygen and tested against models simulating a normal lung, a low compliance (Acute Respiratory Distress Syndrome) lung and a high-resistance (asthma) lung. Ventilators were tested at a range of simulated altitudes between sea level and 3048 m. Over this range, tidal volume delivered by the Oxylog 1000 increased by 68% and respiratory rate decreased by 28%. Tidal volume delivered by the Oxylog 2000 ventilator increased by 29% over the same range of altitudes but there was no significant change in respiratory rate. Tidal volume and respiratory rate remained constant with the Oxylog 3000 over the same range of altitudes. Changes were consistent with each ventilator regardless of oxygen content or lung model. It is important that clinicians involved in critical care transport in a hypobaric environment are aware that individual ventilators perform differently at altitude and that they are aware of the characteristics of the particular ventilator that they are using.

  12. Using queuing theory and simulation model to optimize hospital pharmacy performance.

    Science.gov (United States)

    Bahadori, Mohammadkarim; Mohammadnejhad, Seyed Mohsen; Ravangard, Ramin; Teymourzadeh, Ehsan

    2014-03-01

    Hospital pharmacy is responsible for controlling and monitoring the medication use process and ensures the timely access to safe, effective and economical use of drugs and medicines for patients and hospital staff. This study aimed to optimize the management of studied outpatient pharmacy by developing suitable queuing theory and simulation technique. A descriptive-analytical study conducted in a military hospital in Iran, Tehran in 2013. A sample of 220 patients referred to the outpatient pharmacy of the hospital in two shifts, morning and evening, was selected to collect the necessary data to determine the arrival rate, service rate, and other data needed to calculate the patients flow and queuing network performance variables. After the initial analysis of collected data using the software SPSS 18, the pharmacy queuing network performance indicators were calculated for both shifts. Then, based on collected data and to provide appropriate solutions, the queuing system of current situation for both shifts was modeled and simulated using the software ARENA 12 and 4 scenarios were explored. Results showed that the queue characteristics of the studied pharmacy during the situation analysis were very undesirable in both morning and evening shifts. The average numbers of patients in the pharmacy were 19.21 and 14.66 in the morning and evening, respectively. The average times spent in the system by clients were 39 minutes in the morning and 35 minutes in the evening. The system utilization in the morning and evening were, respectively, 25% and 21%. The simulation results showed that reducing the staff in the morning from 2 to 1 in the receiving prescriptions stage didn't change the queue performance indicators. Increasing one staff in filling prescription drugs could cause a decrease of 10 persons in the average queue length and 18 minutes and 14 seconds in the average waiting time. On the other hand, simulation results showed that in the evening, decreasing the staff

  13. Using Queuing Theory and Simulation Model to Optimize Hospital Pharmacy Performance

    Science.gov (United States)

    Bahadori, Mohammadkarim; Mohammadnejhad, Seyed Mohsen; Ravangard, Ramin; Teymourzadeh, Ehsan

    2014-01-01

    Background: Hospital pharmacy is responsible for controlling and monitoring the medication use process and ensures the timely access to safe, effective and economical use of drugs and medicines for patients and hospital staff. Objectives: This study aimed to optimize the management of studied outpatient pharmacy by developing suitable queuing theory and simulation technique. Patients and Methods: A descriptive-analytical study conducted in a military hospital in Iran, Tehran in 2013. A sample of 220 patients referred to the outpatient pharmacy of the hospital in two shifts, morning and evening, was selected to collect the necessary data to determine the arrival rate, service rate, and other data needed to calculate the patients flow and queuing network performance variables. After the initial analysis of collected data using the software SPSS 18, the pharmacy queuing network performance indicators were calculated for both shifts. Then, based on collected data and to provide appropriate solutions, the queuing system of current situation for both shifts was modeled and simulated using the software ARENA 12 and 4 scenarios were explored. Results: Results showed that the queue characteristics of the studied pharmacy during the situation analysis were very undesirable in both morning and evening shifts. The average numbers of patients in the pharmacy were 19.21 and 14.66 in the morning and evening, respectively. The average times spent in the system by clients were 39 minutes in the morning and 35 minutes in the evening. The system utilization in the morning and evening were, respectively, 25% and 21%. The simulation results showed that reducing the staff in the morning from 2 to 1 in the receiving prescriptions stage didn't change the queue performance indicators. Increasing one staff in filling prescription drugs could cause a decrease of 10 persons in the average queue length and 18 minutes and 14 seconds in the average waiting time. On the other hand, simulation

  14. Development of VIPER: a simulator for assessing vision performance of warfighters

    Science.gov (United States)

    Familoni, Jide; Thompson, Roger; Moyer, Steve; Mueller, Gregory; Williams, Tim; Nguyen, Hung-Quang; Espinola, Richard L.; Sia, Rose K.; Ryan, Denise S.; Rivers, Bruce A.

    2016-05-01

    Background: When evaluating vision, it is important to assess not just the ability to read letters on a vision chart, but also how well one sees in real life scenarios. As part of the Warfighter Refractive Eye Surgery Program (WRESP), visual outcomes are assessed before and after refractive surgery. A Warfighter's ability to read signs and detect and identify objects is crucial, not only when deployed in a military setting, but also in their civilian lives. Objective: VIPER, a VIsion PERformance simulator was envisioned as actual video-based simulated driving to test warfighters' functional vision under realistic conditions. Designed to use interactive video image controlled environments at daytime, dusk, night, and with thermal imaging vision, it simulates the experience of viewing and identifying road signs and other objects while driving. We hypothesize that VIPER will facilitate efficient and quantifiable assessment of changes in vision and measurement of functional military performance. Study Design: Video images were recorded on an isolated 1.1 mile stretch of road with separate target sets of six simulated road signs and six objects of military interest, separately. The video footage were integrated with customdesigned C++ based software that presented the simulated drive to an observer on a computer monitor at 10, 20 or 30 miles/hour. VIPER permits the observer to indicate when a target is seen and when it is identified. Distances at which the observer recognizes and identifies targets are automatically logged. Errors in recognition and identification are also recorded. This first report describes VIPER's development and a preliminary study to establish a baseline for its performance. In the study, nine soldiers viewed simulations at 10 miles/hour and 30 miles/hour, run in randomized order for each participant seated at 36 inches from the monitor. Relevance: Ultimately, patients are interested in how their vision will affect their ability to perform daily

  15. OPERA-a human performance database under simulated emergencies of nuclear power plants

    International Nuclear Information System (INIS)

    Park, Jinkyun; Jung, Wondea

    2007-01-01

    In complex systems such as the nuclear and chemical industry, the importance of human performance related problems is well recognized. Thus a lot of effort has been spent on this area, and one of the main streams for unraveling human performance related problems is the execution of HRA. Unfortunately a lack of prerequisite information has been pointed out as the most critical problem in conducting HRA. From this necessity, OPERA database that can provide operators' performance data obtained under simulated emergencies has been developed. In this study, typical operators' performance data that are available from OPERA database are briefly explained. After that, in order to ensure the appropriateness of OPERA database, operators' performance data from OPERA database are compared with those of other studies and real events. As a result, it is believed that operators' performance data of OPERA database are fairly comparable to those of other studies and real events. Therefore it is meaningful to expect that OPERA database can be used as a serviceable data source for scrutinizing human performance related problems including HRA

  16. Results and Lessons Learned from Performance Testing of Humans in Spacesuits in Simulated Reduced Gravity

    Science.gov (United States)

    Chappell, Steven P.; Norcross, Jason R.; Gernhardt, Michael L.

    2009-01-01

    NASA's Constellation Program has plans to return to the Moon within the next 10 years. Although reaching the Moon during the Apollo Program was a remarkable human engineering achievement, fewer than 20 extravehicular activities (EVAs) were performed. Current projections indicate that the next lunar exploration program will require thousands of EVAs, which will require spacesuits that are better optimized for human performance. Limited mobility and dexterity, and the position of the center of gravity (CG) are a few of many features of the Apollo suit that required significant crew compensation to accomplish the objectives. Development of a new EVA suit system will ideally result in performance close to or better than that in shirtsleeves at 1 G, i.e., in "a suit that is a pleasure to work in, one that you would want to go out and explore in on your day off." Unlike the Shuttle program, in which only a fraction of the crew perform EVA, the Constellation program will require that all crewmembers be able to perform EVA. As a result, suits must be built to accommodate and optimize performance for a larger range of crew anthropometry, strength, and endurance. To address these concerns, NASA has begun a series of tests to better understand the factors affecting human performance and how to utilize various lunar gravity simulation environments available for testing.

  17. Study on performance simulation of polymer electrolyte fuel cell for preventing degradation

    International Nuclear Information System (INIS)

    Kobayashi, T; Doi, M; Fukuda, T; Hashimoto, R; Kanematsu, H; Utsumi, Y

    2013-01-01

    In the present study, the distribution of water content in the membrane of PEFC was analyzed by using a numerical simulation as well as understanding the behavior of internal moisture of PEFC. Eight parameters were selected for the simulation then 18 combinations of the parameters were allocated by design of experiments, thus the data obtained were analyzed by multiple regression analysis to understand the influence factor of operating conditions quantitatively. As a result, the influence of the operating parameters on the dryness of the membrane for the anode side and the cathode side of PEFC was quantitatively shown by using the method of the multiple regression analysis. Further it was found that the area where cerium carbonate ought to be coated for preventing the degradation without decreasing performance.

  18. Towards a benchmark simulation model for plant-wide control strategy performance evaluation of WWTPs

    DEFF Research Database (Denmark)

    Jeppsson, Ulf; Rosen, Christian; Alex, Jens

    2006-01-01

    The COST/IWA benchmark simulation model has been available for seven years. Its primary purpose has been to create a platform for control strategy benchmarking of activated sludge processes. The fact that the benchmark has resulted in more than 100 publications, not only in Europe but also...... worldwide, demonstrates the interest in such a tool within the research community In this paper, an extension of the benchmark simulation model no 1 (BSM1) is proposed. This extension aims at facilitating control strategy development and performance evaluation at a plant-wide level and, consequently...... the changes, the evaluation period has been extended to one year. A prolonged evaluation period allows for long-term control strategies to be assessed and enables the use of control handles that cannot be evaluated in a realistic fashion in the one-week BSM1 evaluation period. In the paper, the extended plant...

  19. Time-domain simulation and nonlinear analysis on ride performance of four-wheel vehicles

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Y S; He, H; Geng, A L [School of Automobile and Traffic Engineering, Liaoning University of Technology, Jinzhou 121001 (China)], E-mail: jzwbt@163.com

    2008-02-15

    A nonlinear dynamic model with eight DOFs of a four-wheel vehicle is established in this paper. After detaching the nonlinear characteristics of the leaf springs and shock absorbers, the multi-step linearizing method is used to simulate the vehicle vibration in time domain, under a correlated four-wheel road roughness model. Experimental verifications suggest that the newly built vehicle model and simulation procedure are reasonable and feasible to be used in vehicle vibration analysis. Furthermore, some nonlinear factors of the leaf springs and shock absorbers, which affect the vehicle ride performance (or comfort), are investigated under different vehicle running speeds. Some substaintial rules of the nonlinear vehicle vibrations are revealed in this paper.

  20. Time-domain simulation and nonlinear analysis on ride performance of four-wheel vehicles

    International Nuclear Information System (INIS)

    Wang, Y S; He, H; Geng, A L

    2008-01-01

    A nonlinear dynamic model with eight DOFs of a four-wheel vehicle is established in this paper. After detaching the nonlinear characteristics of the leaf springs and shock absorbers, the multi-step linearizing method is used to simulate the vehicle vibration in time domain, under a correlated four-wheel road roughness model. Experimental verifications suggest that the newly built vehicle model and simulation procedure are reasonable and feasible to be used in vehicle vibration analysis. Furthermore, some nonlinear factors of the leaf springs and shock absorbers, which affect the vehicle ride performance (or comfort), are investigated under different vehicle running speeds. Some substaintial rules of the nonlinear vehicle vibrations are revealed in this paper

  1. Numerical simulation for rib and channel position effect on PEMFC performances

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Zhixiang; Wang, Cheng; Mao, Zongqiang [Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084 (China); Zhang, Haiyong [Lab of Sail, Cable and Paints, Navy Equipment Technology Institute, Beijing, 102442 (China)

    2010-04-15

    Simulation is an important method for engineers to probe the detailed transportation and reaction information inside fuel cells and guide their designs without large amount of experiments. Although many papers discussing fuel cell flow fields design could be found in documents, relative positions of the ribs and channels in the anode and cathode flow field plates haven't been paid attention to surprisingly. In this paper, simulation results were given to explain the influences of relative positions of the ribs and channels in the anode and cathode flow field plates on the proton exchange membrane fuel cell (PEMFC) performances. It is interesting that the influence differs with several factors and the information will be helpful for fuel cell design. (author)

  2. Simulated performance of the in-beam conversion-electron spectrometer, SPICE

    Energy Technology Data Exchange (ETDEWEB)

    Ketelhut, S., E-mail: ketelhut@triumf.ca [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2A3 (Canada); Evitts, L.J.; Garnsworthy, A.B.; Bolton, C.; Ball, G.C.; Churchman, R. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2A3 (Canada); Dunlop, R. [Department of Physics, University of Guelph, Guelph, Ontario, Canada N1G 2W1 (Canada); Hackman, G.; Henderson, R.; Moukaddam, M. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2A3 (Canada); Rand, E.T.; Svensson, C.E. [Department of Physics, University of Guelph, Guelph, Ontario, Canada N1G 2W1 (Canada); Witmer, J. [TRIUMF, 4004 Wesbrook Mall, Vancouver, British Columbia, Canada V6T 2A3 (Canada)

    2014-07-01

    The SPICE spectrometer is a new in-beam electron spectrometer designed to operate in conjunction with the TIGRESS HPGe Clover array at TRIUMF-ISAC. The spectrometer consists of a large area, annular, segmented lithium-drifted silicon electron detector shielded from the target by a photon shield. A permanent magnetic lens directs electrons around the photon shield to the detector. Experiments will be performed utilising Coulomb excitation, inelastic-scattering, transfer and fusion–evaporation reactions using stable and radioactive ion beams with suitable heavy-ion detection. Good detection efficiency can be achieved in a large energy range up to 3500 keV electron energy using several magnetic lens designs which are quickly interchangeable. COMSOL and Geant4 simulations have been used to maximise the detection efficiency. In addition, the simulations have guided the design of components to minimise the contributions from various sources of backgrounds.

  3. Analysis OpenMP performance of AMD and Intel architecture for breaking waves simulation using MPS

    Science.gov (United States)

    Alamsyah, M. N. A.; Utomo, A.; Gunawan, P. H.

    2018-03-01

    Simulation of breaking waves by using Navier-Stokes equation via moving particle semi-implicit method (MPS) over close domain is given. The results show the parallel computing on multicore architecture using OpenMP platform can reduce the computational time almost half of the serial time. Here, the comparison using two computer architectures (AMD and Intel) are performed. The results using Intel architecture is shown better than AMD architecture in CPU time. However, in efficiency, the computer with AMD architecture gives slightly higher than the Intel. For the simulation by 1512 number of particles, the CPU time using Intel and AMD are 12662.47 and 28282.30 respectively. Moreover, the efficiency using similar number of particles, AMD obtains 50.09 % and Intel up to 49.42 %.

  4. Comparison of Two Models for Damage Accumulation in Simulations of System Performance

    Energy Technology Data Exchange (ETDEWEB)

    Youngblood, R. [Idaho National Laboratory, Idaho Falls, ID (United States); Mandelli, D. [Idaho National Laboratory, Idaho Falls, ID (United States)

    2015-11-01

    A comprehensive simulation study of system performance needs to address variations in component behavior, variations in phenomenology, and the coupling between phenomenology and component failure. This paper discusses two models of this: 1. damage accumulation is modeled as a random walk process in each time history, with component failure occurring when damage accumulation reaches a specified threshold; or 2. damage accumulation is modeled mechanistically within each time history, but failure occurs when damage reaches a time-history-specific threshold, sampled at time zero from each component’s distribution of damage tolerance. A limiting case of the latter is classical discrete-event simulation, with component failure times sampled a priori from failure time distributions; but in such models, the failure times are not typically adjusted for operating conditions varying within a time history. Nowadays, as discussed below, it is practical to account for this. The paper compares the interpretations and computational aspects of the two models mentioned above.

  5. Performance modeling & simulation of complex systems (A systems engineering design & analysis approach)

    Science.gov (United States)

    Hall, Laverne

    1995-01-01

    Modeling of the Multi-mission Image Processing System (MIPS) will be described as an example of the use of a modeling tool to design a distributed system that supports multiple application scenarios. This paper examines: (a) modeling tool selection, capabilities, and operation (namely NETWORK 2.5 by CACl), (b) pointers for building or constructing a model and how the MIPS model was developed, (c) the importance of benchmarking or testing the performance of equipment/subsystems being considered for incorporation the design/architecture, (d) the essential step of model validation and/or calibration using the benchmark results, (e) sample simulation results from the MIPS model, and (f) how modeling and simulation analysis affected the MIPS design process by having a supportive and informative impact.

  6. Performance simulation and structure design of Binode CdZnTe gamma-ray detector

    International Nuclear Information System (INIS)

    Niu Libo; Li Yulan; Fu Jianqiang; Jiang Hao; Zhang Lan; He Bin; Li Yuanjing

    2014-01-01

    A new electrode structure CdZnTe (Cadmium Zinc Telluride) detector named Binode CdZnTe has been pro- posed in this paper. Together with the softwares of MAXWELL, GEANT4, and ROOT, the charge collection process and its gamma spectrum of the detector have been simulated and the detector structure has been optimized. In order to improve its performance further, Compton scattering effect correction has been used. The simulation results demonstrate that with refined design and Compton scattering effect correction, Binode CdZnTe detectors is capable of achieving 3.92% FWHM at 122 keV, and 1.27% FWHM at 662 keV. Com- pared with other single-polarity (electron-only) detector configurations, Binode CdZnTe detector offers a cost effective and simple structure alternative with comparable energy resolution. (authors)

  7. Influence of videogames and musical instruments on performances at a simulator for robotic surgery.

    Science.gov (United States)

    Moglia, Andrea; Perrone, Vittorio; Ferrari, Vincenzo; Morelli, Luca; Boggi, Ugo; Ferrari, Mauro; Mosca, Franco; Cuschieri, Alfred

    2017-06-01

    To assess if exposure to videogames, musical instrument playing, or both influence the psychomotor skills level, assessed by a virtual reality simulator for robot-assisted surgery (RAS). A cohort of 57 medical students were recruited: playing musical instruments (group 1), videogames (group 2), both (group 3), and no activity (group 4); all students executed four exercises on a virtual simulator for RAS. Subjects from group 3 achieved the best performances on overall score: 527.09 ± 130.54 vs. 493.73 ± 108.88 (group 2), 472.72 ± 85.31 (group 1), and 403.13 ± 99.83 (group 4). Statistically significant differences (p videogames is higher than that in those practicing either one alone. The effect of videogames appears negligible in individuals playing the piano.

  8. Simulating Effects of High Angle of Attack on Turbofan Engine Performance

    Science.gov (United States)

    Liu, Yuan; Claus, Russell W.; Litt, Jonathan S.; Guo, Ten-Huei

    2013-01-01

    A method of investigating the effects of high angle of attack (AOA) flight on turbofan engine performance is presented. The methodology involves combining a suite of diverse simulation tools. Three-dimensional, steady-state computational fluid dynamics (CFD) software is used to model the change in performance of a commercial aircraft-type inlet and fan geometry due to various levels of AOA. Parallel compressor theory is then applied to assimilate the CFD data with a zero-dimensional, nonlinear, dynamic turbofan engine model. The combined model shows that high AOA operation degrades fan performance and, thus, negatively impacts compressor stability margins and engine thrust. In addition, the engine response to high AOA conditions is shown to be highly dependent upon the type of control system employed.

  9. Simulated Performances of a Very High Energy Tomograph for Non-Destructive Characterization of large objects

    Directory of Open Access Journals (Sweden)

    Kistler Marc

    2018-01-01

    The upgrade of the detection part needs a thorough study of the performance of two detectors: a series of CdTe semiconductor sensors and two arrays of segmented CdWO4 scintillators with different pixel sizes. This study consists in a Quantum Accounting Diagram (QAD analysis coupled with Monte-Carlo simulations. The scintillator arrays are able to detect millimeter details through 140 cm of concrete, but are limited to 120 cm for smaller ones. CdTe sensors have lower but more stable performance, with a 0.5 mm resolution for 90 cm of concrete. The choice of the detector then depends on the preferred characteristic: the spatial resolution or the use on large volumes. The combination of the features of the source and the studies on the detectors gives the expected performance of the whole equipment, in terms of signal-over-noise ratio (SNR, spatial resolution and acquisition time.

  10. Numerical simulation of unsteady free surface flow and dynamic performance for a Pelton turbine

    International Nuclear Information System (INIS)

    Xiao, Y X; Wang, Z W; Yan, Z G; Cui, T

    2012-01-01

    Different from the reaction turbines, the hydraulic performance of the Pelton turbine is dynamic due to the unsteady free surface flow in the rotating buckets in time and space. This paper aims to present the results of investigations conducted on the free surface flow in a Pelton turbine rotating buckets. The unsteady numerical simulations were performed with the CFX code by using the Realizable k-ε turbulence model coupling the two-phase flow volume of fluid method. The unsteady free surface flow patterns and torque varying with the bucket rotating were analysed. The predicted relative performance at five operating conditions was compared with the field test results. The study was also conducted the interactions between the bucket rear and the water jet.

  11. Numerical simulation of unsteady free surface flow and dynamic performance for a Pelton turbine

    Science.gov (United States)

    Xiao, Y. X.; Cui, T.; Wang, Z. W.; Yan, Z. G.

    2012-11-01

    Different from the reaction turbines, the hydraulic performance of the Pelton turbine is dynamic due to the unsteady free surface flow in the rotating buckets in time and space. This paper aims to present the results of investigations conducted on the free surface flow in a Pelton turbine rotating buckets. The unsteady numerical simulations were performed with the CFX code by using the Realizable k-ε turbulence model coupling the two-phase flow volume of fluid method. The unsteady free surface flow patterns and torque varying with the bucket rotating were analysed. The predicted relative performance at five operating conditions was compared with the field test results. The study was also conducted the interactions between the bucket rear and the water jet.

  12. An evaluation of performance by older persons on a simulated telecommuting task.

    Science.gov (United States)

    Sharit, Joseph; Czaja, Sara J; Hernandez, Mario; Yang, Yulong; Perdomo, Dolores; Lewis, John E; Lee, Chin Chin; Nair, Sankaran

    2004-11-01

    Telecommuting work represents a strategy for managing the growing number of older people in the workforce. This study involved a simulated customer service telecommuting task that used e-mail to answer customer queries about media-related products and company policies. Participants included 27 "younger" older adults (50-65 years) and 25 "older" older adults (66-80 years). The participants performed the task for two 2-hr sessions a day over 4 consecutive days. Although both age groups showed significant improvement across sessions on many of the performance criteria, in general the improvements were more marked for the older age-group participants. However, the participants from both age groups had difficulty meeting some of the task performance requirements. These results are discussed in terms of training strategies for older workers.

  13. Cognitive load, emotion, and performance in high-fidelity simulation among beginning nursing students: a pilot study.

    Science.gov (United States)

    Schlairet, Maura C; Schlairet, Timothy James; Sauls, Denise H; Bellflowers, Lois

    2015-03-01

    Establishing the impact of the high-fidelity simulation environment on student performance, as well as identifying factors that could predict learning, would refine simulation outcome expectations among educators. The purpose of this quasi-experimental pilot study was to explore the impact of simulation on emotion and cognitive load among beginning nursing students. Forty baccalaureate nursing students participated in teaching simulations, rated their emotional state and cognitive load, and completed evaluation simulations. Two principal components of emotion were identified representing the pleasant activation and pleasant deactivation components of affect. Mean rating of cognitive load following simulation was high. Linear regression identiffed slight but statistically nonsignificant positive associations between principal components of emotion and cognitive load. Logistic regression identified a negative but statistically nonsignificant effect of cognitive load on assessment performance. Among lower ability students, a more pronounced effect of cognitive load on assessment performance was observed; this also was statistically non-significant. Copyright 2015, SLACK Incorporated.

  14. Performance of Regional Climate Model in Simulating Monsoon Onset Over Indian Subcontinent

    Science.gov (United States)

    Bhatla, R.; Mandal, B.; Verma, Shruti; Ghosh, Soumik; Mall, R. K.

    2018-06-01

    The performance of various Convective Parameterization Schemes (CPSs) of Regional Climate Model version 4.3 (RegCM-4.3) for simulation of onset phase of Indian summer monsoon (ISM) over Kerala was studied for the period of 2001-2010. The onset date and its associated spatial variation were simulated using RegCM-4.3 four core CPS, namely Kuo, Tiedtke, Emanuel and Grell; and with two mixed convection schemes Mix98 (Emanuel over land and Grell over ocean) and Mix99 (Grell over land and Emanuel over ocean) on the basis of criteria given by the India Meteorological Department (IMD) (Pai and Rajeevan in Indian summer monsoon onset: variability and prediction. National Climate Centre, India Meteorological Department, 2007). It has been found that out of six CPS, two schemes, namely Tiedtke and Mix99 simulated the onset date properly. The onset phase is characterized with several transition phases of atmosphere. Therefore, to study the thermal response or the effect of different sea surface temperature (SST), namely ERA interim (ERSST) and weekly optimal interpolation (OI_WK SST) on Indian summer monsoon, the role of two different types of SST has been used to investigate the simulated onset date. In addition, spatial atmospheric circulation pattern during onset phase were analyzed using reanalyze dataset of ERA Interim (EIN15) and National Oceanic and Atmospheric Administration (NOAA), respectively, for wind and outgoing long-wave radiation (OLR) pattern. Among the six convective schemes of RegCM-4.3 model, Tiedtke is in good agreement with actual onset dates and OI_WK SST forcing is better for simulating onset of ISM over Kerala.

  15. Experiment and Simulation Study of Single Cylinder Diesel Engine Performance, Using Soybean Oil Biodiesel

    Directory of Open Access Journals (Sweden)

    Muhammad Rizqi Ariefianto

    2017-01-01

    Full Text Available Abstract— The most common fuel uses in the world is made from fossil. Fossil fuel is categorized as a non-renewable energy source. For that reason, there should be an alternative fuel to replace fossil fuel by using biodiesel and one of the stock comes from soybean bean. Before using the biodiesel made from soybean bean oil, there should be a research to find out the properties and the effect of biodiesel from soybean bean oil regarding the performance of the engine. The research can be conducted in experiment and simulation. The properties result of soybean oil biodiesel should be tested to confirm whether this biodiesel have meet the standard requirement of biodieselor not. This biodiesel sproperties are Flash Point value is 182 o C , Pour Point value is -7 o C, Density at 15 o C is 890 Kg/m3, Kinematic Viscosity at 40 o C is 5.58 (cSt, and Lower Heating Value is 42.27686 MJ/kg. The result from this research is the highest power from simulation is 9% higher than the experiment. The highest torque from the experiment is 37% lower than the simulation’s torque. Lowest SFOC from experiment is  28% lower than the simulation’s SFOC. Highest BMEP from simulation is 20% higher than the highest BMEP from experiment. The  highest thermal efficiency from experiment is 6% higher than the highest thermal efficiency from simulation. The engine performance result using soybean oil biodiesel is not better than the Pertamina Dex. For that reason, the use of this biodiesel is not suggested to substitute Pertamina Dex.

  16. Simulation of performance of centrifugal circulators with vaneless diffuser for GCR applications

    International Nuclear Information System (INIS)

    Tauveron, N.; Dor, I.

    2010-01-01

    In the frame of the international forum GenIV, CEA has selected various innovative concepts of gas-cooled nuclear reactor. Thermal hydraulic performances are a key issue for the design. For transient conditions and decay heat removal situations, the thermal hydraulic performance must remain as high as possible. In this context, all the transient situations, the incidental and accidental scenarii must be evaluated by a validated system code able to correctly describe, in particular, the thermal hydraulics of the whole plant. As concepts use a helium compressor to maintain the flow in the core, a special emphasis must be laid on compressor modelling. Centrifugal circulators with a vaneless diffuser have significant properties in term of simplicity, cost, ability to operate over a wide range of conditions. The objective of this paper is to present a dedicated description of centrifugal compressor, based on a one-dimensional approach. This type of model requires various correlations as input data. The present contribution consists in establishing and validating the numerical simulations (including different sets of correlations) by comparison with representative experimental data. The results obtained show a qualitatively correct behaviour of the model compared to open literature cases of the gas turbine aircraft community and helium circulators of high temperature gas reactors. The model is finally used in a depressurised transient simulation of a small power gas fast reactor (ALLEGRO concept). Advantages of this model versus first preliminary simulations are shown. Further work on modelling and validation are nevertheless needed to have a better confidence in the simulation predictions.

  17. Simulation of performance of centrifugal circulators with vaneless diffuser for GCR applications

    Energy Technology Data Exchange (ETDEWEB)

    Tauveron, N., E-mail: nicolas.tauveron@cea.f [CEA, DEN, DER/SSTH, 17 rue des Martyrs, F-38054 Grenoble (France); Dor, I., E-mail: isabelle.dor@cea.f [CEA, DEN, DER/SSTH, 17 rue des Martyrs, F-38054 Grenoble (France)

    2010-10-15

    In the frame of the international forum GenIV, CEA has selected various innovative concepts of gas-cooled nuclear reactor. Thermal hydraulic performances are a key issue for the design. For transient conditions and decay heat removal situations, the thermal hydraulic performance must remain as high as possible. In this context, all the transient situations, the incidental and accidental scenarii must be evaluated by a validated system code able to correctly describe, in particular, the thermal hydraulics of the whole plant. As concepts use a helium compressor to maintain the flow in the core, a special emphasis must be laid on compressor modelling. Centrifugal circulators with a vaneless diffuser have significant properties in term of simplicity, cost, ability to operate over a wide range of conditions. The objective of this paper is to present a dedicated description of centrifugal compressor, based on a one-dimensional approach. This type of model requires various correlations as input data. The present contribution consists in establishing and validating the numerical simulations (including different sets of correlations) by comparison with representative experimental data. The results obtained show a qualitatively correct behaviour of the model compared to open literature cases of the gas turbine aircraft community and helium circulators of high temperature gas reactors. The model is finally used in a depressurised transient simulation of a small power gas fast reactor (ALLEGRO concept). Advantages of this model versus first preliminary simulations are shown. Further work on modelling and validation are nevertheless needed to have a better confidence in the simulation predictions.

  18. The influence of anaesthetists' experience on workload, performance and visual attention during simulated critical incidents.

    Science.gov (United States)

    Schulz, Christian M; Schneider, Erich; Kohlbecher, Stefan; Hap