Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721585
Mohammad F. Obeid, John B. Shull
After its first introduction in 1999, West Nile Virus (WNV) has spread very widely along the east coasts of the United States before appearing in Texas where 1792 cases were reported of which 82 were fatal in 2012. The interesting patterns and behavior of the virus and its amplified impact on the county of Dallas drove this work. This paper encompasses a thorough development of a systems dynamics simulation model that imitates the virus's infectious behavior and dynamics in Dallas County, TX utilizing historical data collected and the aid of suitable software packages.
{"title":"West Nile Virus system dynamics investigation in Dallas County, TX","authors":"Mohammad F. Obeid, John B. Shull","doi":"10.1109/WSC.2013.6721585","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721585","url":null,"abstract":"After its first introduction in 1999, West Nile Virus (WNV) has spread very widely along the east coasts of the United States before appearing in Texas where 1792 cases were reported of which 82 were fatal in 2012. The interesting patterns and behavior of the virus and its amplified impact on the county of Dallas drove this work. This paper encompasses a thorough development of a systems dynamics simulation model that imitates the virus's infectious behavior and dynamics in Dallas County, TX utilizing historical data collected and the aid of suitable software packages.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127125576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721455
C. Alexopoulos, D. Goldsman, Peng Tang, James R. Wilson
We propose SPSTS, an automated sequential procedure for computing point and confidence-interval (CI) estimators for the steady-state mean of a simulation output process. This procedure is based on variance estimators computed from standardized time series, and it is characterized by its simplicity relative to methods based on batch means and its ability to deliver CIs for the variance parameter of the output process. The effectiveness of SPSTS is evaluated via comparisons with methods based on batch means. In preliminary experimentation with the steady-state waiting-time process for the M/M/1 queue with a server utilization of 90%, we found that SPSTS performed comparatively well in terms of its average required sample size as well as the coverage and average half-length of its delivered CIs.
{"title":"A sequential procedure for estimating the steady-state mean using standardized time series","authors":"C. Alexopoulos, D. Goldsman, Peng Tang, James R. Wilson","doi":"10.1109/WSC.2013.6721455","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721455","url":null,"abstract":"We propose SPSTS, an automated sequential procedure for computing point and confidence-interval (CI) estimators for the steady-state mean of a simulation output process. This procedure is based on variance estimators computed from standardized time series, and it is characterized by its simplicity relative to methods based on batch means and its ability to deliver CIs for the variance parameter of the output process. The effectiveness of SPSTS is evaluated via comparisons with methods based on batch means. In preliminary experimentation with the steady-state waiting-time process for the M/M/1 queue with a server utilization of 90%, we found that SPSTS performed comparatively well in terms of its average required sample size as well as the coverage and average half-length of its delivered CIs.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124870924","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721685
Trang Dang, H. Bargstädt
In order to improve the flexibility and adaptability of an automated model to various different projects under different circumstances, various solutions should be generated as proposed results, instead of only one solution as in recent research. This paper therefore presents a method for generating a series of reasonably detailed schedules for mapping the workplaces of activities over time. This model incorporates Pareto-based optimization and simulation. The optimization engine takes on the role for generating and choosing good schedules. The simulators, on the other hand, are responsible for manipulating activities to resolve spatial conflicts, to respect the limits of crews and investigate the efficiency of solutions. A prototype implementation is afterwards developed and implemented in software based on Building Information Modeling, which enables the model to automatically retrieve the required geometric data. The output solutions are finally analyzed through an example to prove their feasibility and adaptability to various potential situations.
{"title":"Integration of simulation and Pareto-based optimization for space planning in the finishing phase","authors":"Trang Dang, H. Bargstädt","doi":"10.1109/WSC.2013.6721685","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721685","url":null,"abstract":"In order to improve the flexibility and adaptability of an automated model to various different projects under different circumstances, various solutions should be generated as proposed results, instead of only one solution as in recent research. This paper therefore presents a method for generating a series of reasonably detailed schedules for mapping the workplaces of activities over time. This model incorporates Pareto-based optimization and simulation. The optimization engine takes on the role for generating and choosing good schedules. The simulators, on the other hand, are responsible for manipulating activities to resolve spatial conflicts, to respect the limits of crews and investigate the efficiency of solutions. A prototype implementation is afterwards developed and implemented in software based on Building Information Modeling, which enables the model to automatically retrieve the required geometric data. The output solutions are finally analyzed through an example to prove their feasibility and adaptability to various potential situations.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"80 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124946386","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
The phenomenon of operating system (OS) Jitter has been investigated and considered a critical factor in high-performance computing. In this paper we model and simulate the effects of different sources of OS Jitter in the Linux operating system. We adopt the design of experiments approach to conduct experiments statistically planned. Our simulation models corroborate the results obtained experimentally. We conclude that the OS Jitter has a higher impact when the number of the computational phases is high, for any number of computing nodes from 1 to 500. We also observed that in Linux, the highest OS Jitter impacts are caused by managing the shared processor cache and network interrupts, where the second shows the highest sensitivity with respect to the cluster size.
{"title":"Modeling and simulating the effects of OS Jitter","authors":"Elder Vicente, Rivalino Matias","doi":"10.5555/2675983.2676250","DOIUrl":"https://doi.org/10.5555/2675983.2676250","url":null,"abstract":"The phenomenon of operating system (OS) Jitter has been investigated and considered a critical factor in high-performance computing. In this paper we model and simulate the effects of different sources of OS Jitter in the Linux operating system. We adopt the design of experiments approach to conduct experiments statistically planned. Our simulation models corroborate the results obtained experimentally. We conclude that the OS Jitter has a higher impact when the number of the computational phases is high, for any number of computing nodes from 1 to 500. We also observed that in Linux, the highest OS Jitter impacts are caused by managing the shared processor cache and network interrupts, where the second shows the highest sensitivity with respect to the cluster size.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125094271","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721573
Haidong Xue, Xiaolin Hu
Sequential Monte Carlo (SMC) methods have shown their effectiveness in data assimilation for wildfire simulation; however, when errors of wildfire simulation models are extremely large or rare events happen, the current SMC methods have limited impacts on improving the simulation results. The major problem lies in the proposal distribution that is commonly chosen as the system transition prior in order to avoid difficulties in importance weight updating. In this article, we propose a more effective proposal distribution by taking advantage of information contained in sensor data, and also present a method to solve the problem in weight updating. Experimental results demonstrate that a SMC method with this proposal distribution significantly improves wildfire simulation results when the one with a system transition prior proposal fails.
{"title":"An effective proposal distribution for sequential Monte Carlo methods-based wildfire data assimilation","authors":"Haidong Xue, Xiaolin Hu","doi":"10.1109/WSC.2013.6721573","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721573","url":null,"abstract":"Sequential Monte Carlo (SMC) methods have shown their effectiveness in data assimilation for wildfire simulation; however, when errors of wildfire simulation models are extremely large or rare events happen, the current SMC methods have limited impacts on improving the simulation results. The major problem lies in the proposal distribution that is commonly chosen as the system transition prior in order to avoid difficulties in importance weight updating. In this article, we propose a more effective proposal distribution by taking advantage of information contained in sensor data, and also present a method to solve the problem in weight updating. Experimental results demonstrate that a SMC method with this proposal distribution significantly improves wildfire simulation results when the one with a system transition prior proposal fails.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"97 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126746979","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721531
R. McCune, Rachael Purta, Mikolaj Dobski, Artur Jaworski, Greg Madey, Alexander G. Madey, Y. Wei, M. Brian Blake
The application of Dynamic Data Driven Application Systems (DDDAS) to the command and control of swarms of Unmanned Aerial Vehicles (UAVs) is being investigated. Swarm intelligent systems are not only efficient at solving group-level problems, but also decentralized, controllable by few simple parameters, making possible the command and control of UAV swarms by a single operator. Four separate but related projects are surveyed that explore the command and control of UAV swarms. Each project employs the DDDAS paradigm, entailing the ability of an executing application to incorporate dynamic data into the decision process, and conversely, to steer the measurement process via a central application system. By providing an overview of DDDAS approaches to UAV swarm mission scheduling, UAV swarm communication, UAV swarm formation planning, and flocking applications, general principles of UAV swarms and DDDAS architecture may be observed.
{"title":"Investigations of DDDAS for command and control of UAV swarms with agent-based modeling","authors":"R. McCune, Rachael Purta, Mikolaj Dobski, Artur Jaworski, Greg Madey, Alexander G. Madey, Y. Wei, M. Brian Blake","doi":"10.1109/WSC.2013.6721531","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721531","url":null,"abstract":"The application of Dynamic Data Driven Application Systems (DDDAS) to the command and control of swarms of Unmanned Aerial Vehicles (UAVs) is being investigated. Swarm intelligent systems are not only efficient at solving group-level problems, but also decentralized, controllable by few simple parameters, making possible the command and control of UAV swarms by a single operator. Four separate but related projects are surveyed that explore the command and control of UAV swarms. Each project employs the DDDAS paradigm, entailing the ability of an executing application to incorporate dynamic data into the decision process, and conversely, to steer the measurement process via a central application system. By providing an overview of DDDAS approaches to UAV swarm mission scheduling, UAV swarm communication, UAV swarm formation planning, and flocking applications, general principles of UAV swarms and DDDAS architecture may be observed.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115051457","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721703
Jeff Young
July 1, 2013 will usher in new revisions to the current Federal Motor Carrier Safety Administration's Hours of Service (HOS) regulations governing hours of service for drivers of Commercial Motor Vehicles. This paper will chronicle the modeling approach and preliminary results of the performance impact of the two most significant 2013 HOS regulation changes on a large random over-the-road (OTR) trucking fleet operating in North America. The ultimate goal of this modeling analysis was to provide data to quantify the pending impact of the regulation changes to guide company strategies to mitigate risk and provide a foundation for proactive customer communications. The simulation model was successfully validated by comparing simulated fleet performance against actual fleet performance. Results have been used to communicate impact to internal company stake holders, industry analysts, and customers, along with prompting detailed fleet studies to identify strategies to minimize impact to high risk customers.
2013年7月1日，联邦汽车运输安全管理局(Federal Motor Carrier Safety Administration，简称HOS)关于商用机动车驾驶员服务时间的规定将迎来新的修订。本文将对2013年两项最重要的HOS法规变化对北美大型随机越野(OTR)卡车车队性能影响的建模方法和初步结果进行编年史分析。此建模分析的最终目标是提供数据来量化法规变化的潜在影响，以指导公司降低风险的策略，并为主动与客户沟通提供基础。通过对仿真车队性能与实际车队性能的对比，成功验证了仿真模型的有效性。结果被用于与公司内部股东、行业分析师和客户沟通影响，同时促进详细的车队研究，以确定最小化对高风险客户影响的策略。
{"title":"Simulation-based truck fleet analysis to study the impact of federal motor carrier safety administration's 2013 hours of service regulation changes","authors":"Jeff Young","doi":"10.1109/WSC.2013.6721703","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721703","url":null,"abstract":"July 1, 2013 will usher in new revisions to the current Federal Motor Carrier Safety Administration's Hours of Service (HOS) regulations governing hours of service for drivers of Commercial Motor Vehicles. This paper will chronicle the modeling approach and preliminary results of the performance impact of the two most significant 2013 HOS regulation changes on a large random over-the-road (OTR) trucking fleet operating in North America. The ultimate goal of this modeling analysis was to provide data to quantify the pending impact of the regulation changes to guide company strategies to mitigate risk and provide a foundation for proactive customer communications. The simulation model was successfully validated by comparing simulated fleet performance against actual fleet performance. Results have been used to communicate impact to internal company stake holders, industry analysts, and customers, along with prompting detailed fleet studies to identify strategies to minimize impact to high risk customers.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114151971","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721458
S. Moka, S. Juneja
Conceptually, under restrictions, multiclass open queueing networks are positive Harris recurrent Markov processes, making them amenable to regenerative simulation for estimating the steady-state performance measures. However, regenerations in such networks are difficult to identify when the interarrival times are generally distributed. We assume that the interarrival times have exponential or heavier tails and show that such distributions can be decomposed into mixture of sums of independent random variables such that at least one of the components is exponentially distributed. This allows an implementable regenerative simulation for these networks. We show that the regenerative mean and standard deviation estimators are consistent and satisfy a joint central limit theorem. We also show that amongst all such interarrival decompositions, the one with largest mean exponential component minimizes the asymptotic variance of the standard deviation estimator. We also propose a regenerative simulation method that is applicable even when the interarrival times have superexponential tails.
{"title":"Regenerative simulation for multiclass open queueing networks","authors":"S. Moka, S. Juneja","doi":"10.1109/WSC.2013.6721458","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721458","url":null,"abstract":"Conceptually, under restrictions, multiclass open queueing networks are positive Harris recurrent Markov processes, making them amenable to regenerative simulation for estimating the steady-state performance measures. However, regenerations in such networks are difficult to identify when the interarrival times are generally distributed. We assume that the interarrival times have exponential or heavier tails and show that such distributions can be decomposed into mixture of sums of independent random variables such that at least one of the components is exponentially distributed. This allows an implementable regenerative simulation for these networks. We show that the regenerative mean and standard deviation estimators are consistent and satisfy a joint central limit theorem. We also show that amongst all such interarrival decompositions, the one with largest mean exponential component minimizes the asymptotic variance of the standard deviation estimator. We also propose a regenerative simulation method that is applicable even when the interarrival times have superexponential tails.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128330647","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721607
Ashley Davis, Sanjay Mehrotra, J. Friedewald, D. Ladner
The United Network for Organ Sharing is planning to resolve the ever-growing geographic disparities in kidney transplantation. Currently available simulation techniques are limited in their ability to analyze the impact of policy changes at the system level. This paper discusses the development of a discrete event simulation of the kidney transplantation system, KSIM. KSIM design is discussed and can easily be adapted to test alternative geographic organ allocation policies. Input analysis employing actual transplantation system data was conducted to best represent patient and organ arrival processes. After discussing our model, we briefly describe how KSIM was verified and validated against twenty years of actual transplantation system information. We also describe the potential usability of KSIM in organ allocation policy development.
{"title":"Characteristics of a simulation model of the national kidney transplantation system","authors":"Ashley Davis, Sanjay Mehrotra, J. Friedewald, D. Ladner","doi":"10.1109/WSC.2013.6721607","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721607","url":null,"abstract":"The United Network for Organ Sharing is planning to resolve the ever-growing geographic disparities in kidney transplantation. Currently available simulation techniques are limited in their ability to analyze the impact of policy changes at the system level. This paper discusses the development of a discrete event simulation of the kidney transplantation system, KSIM. KSIM design is discussed and can easily be adapted to test alternative geographic organ allocation policies. Input analysis employing actual transplantation system data was conducted to best represent patient and organ arrival processes. After discussing our model, we briefly describe how KSIM was verified and validated against twenty years of actual transplantation system information. We also describe the potential usability of KSIM in organ allocation policy development.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"39 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128543014","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2013-12-08DOI: 10.1109/WSC.2013.6721415
James Byrne, P. J. Byrne, D. Ferreira, A. Ivers
Discrete event simulation (DES) is a technique used extensively and effectively by large companies, however it is not widely used by small to medium sized enterprises (SMEs) due to complexity and related costs being prohibitively high. In SMEs, DES-related data can be stored in a variety of formats and it is not always evident what data is required (if even available) to support a DES model in relation to specific problem scenarios. Therefore the DES data gathering and preparation phase is where complexity and effort required are highest in order to avoid the potential for erroneous results due to incorrect assumed or real input data. The proposed solution is a Cloud-based adapter that can identify and connect to existing data sources and/or fills gaps in data in relation to defined problem scenarios, thus lowering the barriers for SMEs to gain benefit from DES studies due to reduced complexity and effort.
{"title":"Towards a cloud based SME data adapter for simulation modelling","authors":"James Byrne, P. J. Byrne, D. Ferreira, A. Ivers","doi":"10.1109/WSC.2013.6721415","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721415","url":null,"abstract":"Discrete event simulation (DES) is a technique used extensively and effectively by large companies, however it is not widely used by small to medium sized enterprises (SMEs) due to complexity and related costs being prohibitively high. In SMEs, DES-related data can be stored in a variety of formats and it is not always evident what data is required (if even available) to support a DES model in relation to specific problem scenarios. Therefore the DES data gathering and preparation phase is where complexity and effort required are highest in order to avoid the potential for erroneous results due to incorrect assumed or real input data. The proposed solution is a Cloud-based adapter that can identify and connect to existing data sources and/or fills gaps in data in relation to defined problem scenarios, thus lowering the barriers for SMEs to gain benefit from DES studies due to reduced complexity and effort.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128989032","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
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