This paper presents an online simulation framework that can be used to support operational decisions within the context of Through-life Engineering Services. Acting as a closed-loop feedback control mechanism, the simulation model is physically coupled to the assets and will be triggered and automatically executed to assess a set of operational decisions related to maintenance scheduling, resource allocation, spare parts inventory etc. Experimental cases comparing the online simulation against the traditional approach will also be presented. The outcomes have demonstrated the prospects of the framework in enabling more effective/efficient operations of engineering services leading to high assets availability and reduced through-life costs.
{"title":"An online simulation to link asset condition monitoring and operations decisions in through-life engineering services","authors":"Benny Tjahjono, E. Teixeira, S. C. Alfaro","doi":"10.5555/2675983.2676002","DOIUrl":"https://doi.org/10.5555/2675983.2676002","url":null,"abstract":"This paper presents an online simulation framework that can be used to support operational decisions within the context of Through-life Engineering Services. Acting as a closed-loop feedback control mechanism, the simulation model is physically coupled to the assets and will be triggered and automatically executed to assess a set of operational decisions related to maintenance scheduling, resource allocation, spare parts inventory etc. Experimental cases comparing the online simulation against the traditional approach will also be presented. The outcomes have demonstrated the prospects of the framework in enabling more effective/efficient operations of engineering services leading to high assets availability and reduced through-life costs.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"46 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":"123158313","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.2013.6721667
Yuhao Zheng, Dong Jin, D. Nicol
Large-scale and high-fidelity testbeds play critical roles in analyzing large-scale networks such as data centers, cellular networks, and smart grid control networks. Our prior work combines parallel simulation and virtual-time-integrated emulation, such that it offers both functional and temporal fidelity to the critical software execution in large scale network settings. To achieve better scalability, we have developed a distributed emulation system. However, as the number of computing servers grows, so does too the synchronization overhead. Application lookahead, the ability to predict future behaviors of software, may help reducing overhead for performance gain. In this paper, we study the impacts of application lookahead on our distributed emulation testbed. We find that application lookahead can greatly reduce synchronization overhead and improve speed by up to 3 times in our system, but incorrect lookahead may affect application fidelity to different degrees, depending on application sensitivity to timing.
{"title":"Impacts of application lookahead on distributed network emulation","authors":"Yuhao Zheng, Dong Jin, D. Nicol","doi":"10.1109/WSC.2013.6721667","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721667","url":null,"abstract":"Large-scale and high-fidelity testbeds play critical roles in analyzing large-scale networks such as data centers, cellular networks, and smart grid control networks. Our prior work combines parallel simulation and virtual-time-integrated emulation, such that it offers both functional and temporal fidelity to the critical software execution in large scale network settings. To achieve better scalability, we have developed a distributed emulation system. However, as the number of computing servers grows, so does too the synchronization overhead. Application lookahead, the ability to predict future behaviors of software, may help reducing overhead for performance gain. In this paper, we study the impacts of application lookahead on our distributed emulation testbed. We find that application lookahead can greatly reduce synchronization overhead and improve speed by up to 3 times in our system, but incorrect lookahead may affect application fidelity to different degrees, depending on application sensitivity to timing.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"54 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":"123322440","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.2013.6721695
F. Berner, Vitali Kochkine, I. Habenicht, S. Spieckermann, C. Vath
Optimal planning of construction projects requires an efficient allocation of available resources. Labor, material, equipment are to be planned, coordinated and quickly adapted to varying conditions. Frequent (design) changes during the construction period, diversity of trades and the high complexity of interacting processes in building manufacturing require innovative ways to support process-influencing decisions - a tool which allows testing interventions and adjustments in the manufacturing process, including individual sub-processes with the best possible efficiency. In this context, the discrete-event simulation comes into place. A research group simulated the manufacturing process of a hotel project in all details in order to examine applicability of simulation in the construction industry and to scrutinize and adjust it according to the construction specifics. The approach taken, the challenges encountered and insights gained will be presented in this article.
{"title":"Simulation in manufacturing planning of buildings","authors":"F. Berner, Vitali Kochkine, I. Habenicht, S. Spieckermann, C. Vath","doi":"10.1109/WSC.2013.6721695","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721695","url":null,"abstract":"Optimal planning of construction projects requires an efficient allocation of available resources. Labor, material, equipment are to be planned, coordinated and quickly adapted to varying conditions. Frequent (design) changes during the construction period, diversity of trades and the high complexity of interacting processes in building manufacturing require innovative ways to support process-influencing decisions - a tool which allows testing interventions and adjustments in the manufacturing process, including individual sub-processes with the best possible efficiency. In this context, the discrete-event simulation comes into place. A research group simulated the manufacturing process of a hotel project in all details in order to examine applicability of simulation in the construction industry and to scrutinize and adjust it according to the construction specifics. The approach taken, the challenges encountered and insights gained will be presented in this article.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"22 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":"126562576","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: 10.1002/9780470400531.EORMS0177
S. Robinson
Conceptual modeling is the abstraction of a simulation model from the real world system that is being modeled; in other words, choosing what to model, and what not to model. This is generally agreed to be the most difficult, least understood and most important task to be carried out in a simulation study. In this tutorial the problem of conceptual modeling is first illustrated through an example of modeling a hospital clinic. We then define a set of terminology that helps us frame the conceptual modeling task, we discuss the role of conceptual modeling in the simulation project life-cycle, we identify the requirements for a good conceptual model and we discuss levels of abstraction. A framework that guides the activity of conceptual modeling is described. This framework may also be helpful for teaching effective conceptual modeling.
{"title":"Conceptual modeling for simulation","authors":"S. Robinson","doi":"10.1002/9780470400531.EORMS0177","DOIUrl":"https://doi.org/10.1002/9780470400531.EORMS0177","url":null,"abstract":"Conceptual modeling is the abstraction of a simulation model from the real world system that is being modeled; in other words, choosing what to model, and what not to model. This is generally agreed to be the most difficult, least understood and most important task to be carried out in a simulation study. In this tutorial the problem of conceptual modeling is first illustrated through an example of modeling a hospital clinic. We then define a set of terminology that helps us frame the conceptual modeling task, we discuss the role of conceptual modeling in the simulation project life-cycle, we identify the requirements for a good conceptual model and we discuss levels of abstraction. A framework that guides the activity of conceptual modeling is described. This framework may also be helpful for teaching effective conceptual modeling.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"20 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":"116156584","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.2013.6721513
Ross Gore, S. Diallo
The process of developing, verifying and validating models and simulations should be straightforward. Unfortunately, following conventional development approaches can render a model design that appeared complete and robust into an incomplete, incoherent and invalid simulation during implementation. An alternative approach is for subject matter experts (SMEs) to employ formal methods to describe their models. However, formal methods are rarely used in practice due to their intimidating syntax and semantics rooted in mathematics. In this paper we argue for a new approach to verification and validation that leverages two techniques from computer science: (1) model checking and (2) automated debugging. The proposed vision offers an initial path to replace conventional simulation verification and validation methods with new automated analyses that eventually will be able to yield feedback to SMEs in a familiar language.
{"title":"The need for usable formal methods in verification and validation","authors":"Ross Gore, S. Diallo","doi":"10.1109/WSC.2013.6721513","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721513","url":null,"abstract":"The process of developing, verifying and validating models and simulations should be straightforward. Unfortunately, following conventional development approaches can render a model design that appeared complete and robust into an incomplete, incoherent and invalid simulation during implementation. An alternative approach is for subject matter experts (SMEs) to employ formal methods to describe their models. However, formal methods are rarely used in practice due to their intimidating syntax and semantics rooted in mathematics. In this paper we argue for a new approach to verification and validation that leverages two techniques from computer science: (1) model checking and (2) automated debugging. The proposed vision offers an initial path to replace conventional simulation verification and validation methods with new automated analyses that eventually will be able to yield feedback to SMEs in a familiar language.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"46 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":"116669763","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.2013.6721622
Maria Camila Hoyos, Ridley S. Morales Mahecha, Raha Akhavan-Tabatabaei
Discrete Event Simulation (DES) has been commonly used in modeling the medical attention of injured people. In earthquakes, a portion of the injured victims are trapped and need to be rescued before receiving medical attention. Hence, the rate of rescue operations and the percentage of victims that are rescued have an impact on the logistics planning of medical attention. In this paper we attempt to improve an existing DES model for medical attention to earthquake victims by proposing an improved way of modeling the inter-arrival rate of trapped people. We compare our results with the DES model applied to an earthquake in the city of Bogotá, Colombia and evaluate the difference of additional logistics requirements. The results show that when the percentage of dead people is below 80% there is a significant increase in the expected number of injured victims in the model, when the trapped people are properly included.
{"title":"Modeling the inclusion of trapped victims in logistics planning for earthquake response: A case study in the city of Bogotá","authors":"Maria Camila Hoyos, Ridley S. Morales Mahecha, Raha Akhavan-Tabatabaei","doi":"10.1109/WSC.2013.6721622","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721622","url":null,"abstract":"Discrete Event Simulation (DES) has been commonly used in modeling the medical attention of injured people. In earthquakes, a portion of the injured victims are trapped and need to be rescued before receiving medical attention. Hence, the rate of rescue operations and the percentage of victims that are rescued have an impact on the logistics planning of medical attention. In this paper we attempt to improve an existing DES model for medical attention to earthquake victims by proposing an improved way of modeling the inter-arrival rate of trapped people. We compare our results with the DES model applied to an earthquake in the city of Bogotá, Colombia and evaluate the difference of additional logistics requirements. The results show that when the percentage of dead people is below 80% there is a significant increase in the expected number of injured victims in the model, when the trapped people are properly included.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"6 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":"121494709","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.2013.6721674
Xiaodong Wu, Ming Lu, S. Mao, Xuesong Shen
To fulfill the needs of construction quality, progress control and sustainable development of the underground space, it is desirable to collect and visualize as-built tunnel information in real time. In the current practice, the as-built model of a tunnel is produced either by using advanced technologies like 3D laser scanning after construction ends, or by employing specialist tunnel surveyors to directly measure the invert positions. However, limitations of commonly applied as-built tunnel survey methods are identified in terms of accuracy, cost, or modeling speed. In this paper, we propose a new approach to enabling as-built modeling and visualization of tunnels based on real-time TBM tracking and positioning data. With a tunnel alignment automation control system being implemented, the TBM is turned into a “sensor” to map out as-build information in real time, without incurring extra labor cost or survey equipment. The proposed approach was field-tested and preliminary findings are discussed.
{"title":"As-built modeling and visual simulation of tunnels using real-time TBM positioning data","authors":"Xiaodong Wu, Ming Lu, S. Mao, Xuesong Shen","doi":"10.1109/WSC.2013.6721674","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721674","url":null,"abstract":"To fulfill the needs of construction quality, progress control and sustainable development of the underground space, it is desirable to collect and visualize as-built tunnel information in real time. In the current practice, the as-built model of a tunnel is produced either by using advanced technologies like 3D laser scanning after construction ends, or by employing specialist tunnel surveyors to directly measure the invert positions. However, limitations of commonly applied as-built tunnel survey methods are identified in terms of accuracy, cost, or modeling speed. In this paper, we propose a new approach to enabling as-built modeling and visualization of tunnels based on real-time TBM tracking and positioning data. With a tunnel alignment automation control system being implemented, the TBM is turned into a “sensor” to map out as-build information in real time, without incurring extra labor cost or survey equipment. The proposed approach was field-tested and preliminary findings are discussed.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"30 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":"116601750","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.2013.6721729
G. Rodríguez-Verján, S. Dauzére-Pérés, Sylvain Housseman, J. Pinaton
In this paper, we propose new ways for efficiently managing defect inspection queues in semiconductor manufacturing when a dynamic sampling strategy is used. The objective is to identify lots that can skip the inspection operation, i.e. lots that have limited impact on the risk level of process tools. The risk considered in this paper, called Wafer at Risk (W@R), is the number of wafers processed on a process tool between two defect inspection operations. An indicator (GSI, Global Sampling Indicator) is used to evaluate the overall W@R and another associated indicator (LSI, Lot Scheduling Indicator) is used to identify the impact on the overall risk if a lot is not measured. Based on these indicators, five new algorithms are proposed and tested with industrial instances. Results show the relevance of our approach and that evaluating sets of lots for skipping performs better than evaluating lots individually.
{"title":"Skipping algorithms for defect inspection using a dynamic control strategy in semiconductor manufacturing","authors":"G. Rodríguez-Verján, S. Dauzére-Pérés, Sylvain Housseman, J. Pinaton","doi":"10.1109/WSC.2013.6721729","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721729","url":null,"abstract":"In this paper, we propose new ways for efficiently managing defect inspection queues in semiconductor manufacturing when a dynamic sampling strategy is used. The objective is to identify lots that can skip the inspection operation, i.e. lots that have limited impact on the risk level of process tools. The risk considered in this paper, called Wafer at Risk (W@R), is the number of wafers processed on a process tool between two defect inspection operations. An indicator (GSI, Global Sampling Indicator) is used to evaluate the overall W@R and another associated indicator (LSI, Lot Scheduling Indicator) is used to identify the impact on the overall risk if a lot is not measured. Based on these indicators, five new algorithms are proposed and tested with industrial instances. Results show the relevance of our approach and that evaluating sets of lots for skipping performs better than evaluating lots individually.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"256 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":"122464425","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.2013.6721530
A. Khaleghi, Dong Xu, Alfonso Lobos, S. Minaeian, Y. Son, Jian Liu
An agent-based hardware-in-the-loop simulation framework is proposed to model the UAV/UGV surveillance and crowd control system. To this end, a planning and control system architecture is discussed first, which includes various modules such as sensory data collection, crowd detection, tracking, motion planning, control command generation, and control strategy evaluation. The modules that are highly related with agent-based modeling (focus of this paper) are then discussed, which includes the UAV/UGV motion planning considering multi-objectives, crowd motion modeling via social force model, and enhancement of simulation environment via GIS 3D coordinates conversion. In the experiment, Repast Simphony is used as the agent-based modeling tool, which transmits sensory data and control commands with QGroundControl as hardware interface that further conducts radio communications with ArduCopter as a real UAV. Preliminary results show that finer grid scale and larger vehicle detection range generate a better crowd coverage percentage. Finally, conclusions and future works are discussed.
{"title":"Agent-based hardware-in-the-loop simulation for UAV/UGV surveillance and crowd control system","authors":"A. Khaleghi, Dong Xu, Alfonso Lobos, S. Minaeian, Y. Son, Jian Liu","doi":"10.1109/WSC.2013.6721530","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721530","url":null,"abstract":"An agent-based hardware-in-the-loop simulation framework is proposed to model the UAV/UGV surveillance and crowd control system. To this end, a planning and control system architecture is discussed first, which includes various modules such as sensory data collection, crowd detection, tracking, motion planning, control command generation, and control strategy evaluation. The modules that are highly related with agent-based modeling (focus of this paper) are then discussed, which includes the UAV/UGV motion planning considering multi-objectives, crowd motion modeling via social force model, and enhancement of simulation environment via GIS 3D coordinates conversion. In the experiment, Repast Simphony is used as the agent-based modeling tool, which transmits sensory data and control commands with QGroundControl as hardware interface that further conducts radio communications with ArduCopter as a real UAV. Preliminary results show that finer grid scale and larger vehicle detection range generate a better crowd coverage percentage. Finally, conclusions and future works are discussed.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"5 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":"128073983","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.2013.6721684
Chang Liu, Ming Lu, Sam Johnson
Haulage cost typically accounts for around 30% of the total cost of mass earthmoving projects. The temporary road network is a major factor influencing haulage cost and production efficiency. The simulation of earthmoving operations considering temporary road networks, not only facilitates the site formation design but also leads to realistic, cost-effective construction plans. Utilizing the Floyd-Warshall algorithm and linear programming, this study formulates the temporary road network problem and sheds light on the potential benefits of selecting routes and directions for handling earthmoving jobs. An optimization approach for temporary road networks is further proposed. It reduces the total cost of the project and shortens its duration. Simulation models were used to prove the effectiveness and feasibility of optimization.
{"title":"Simulation and optimization of temporary road network in mass earthmoving projects","authors":"Chang Liu, Ming Lu, Sam Johnson","doi":"10.1109/WSC.2013.6721684","DOIUrl":"https://doi.org/10.1109/WSC.2013.6721684","url":null,"abstract":"Haulage cost typically accounts for around 30% of the total cost of mass earthmoving projects. The temporary road network is a major factor influencing haulage cost and production efficiency. The simulation of earthmoving operations considering temporary road networks, not only facilitates the site formation design but also leads to realistic, cost-effective construction plans. Utilizing the Floyd-Warshall algorithm and linear programming, this study formulates the temporary road network problem and sheds light on the potential benefits of selecting routes and directions for handling earthmoving jobs. An optimization approach for temporary road networks is further proposed. It reduces the total cost of the project and shortens its duration. Simulation models were used to prove the effectiveness and feasibility of optimization.","PeriodicalId":223717,"journal":{"name":"2013 Winter Simulations Conference (WSC)","volume":"33 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":"133539393","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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