Pub Date : 2014-10-01DOI: 10.1109/IECON.2014.7048632
T. Glasberger, T. Komrska, Z. Peroutka
This paper presents a new pulse width modulator dedicated basically for under determined systems. The solution of the under determined problem is performed by minimum 1-inflnity norm solution. One of known under determined system is a four-leg three-phase converter because four reference signals must be created from three control commands. The infinity norm enables to find proper solution to generate corresponding reference signals for the PWM modulator. The designed modulator is implemented with a control system of the four-leg three-phase converter working as an universal supply unit but the proposed modulator is able to operate in arbitrary application with the four-leg converter, generally for arbitrary under-deteremined systems. It is shown in the paper that the known carrier based PWM algorithm represents a subset of modulators utilizing the minimum 1-infinity norm. The theoretical assumptions and the design of the modulator were verified by simulations as well as by experiments on a laboratory prototype of 17 kVA.
{"title":"A minimum infinity norm based PWM modulator for four-leg three-phase converters","authors":"T. Glasberger, T. Komrska, Z. Peroutka","doi":"10.1109/IECON.2014.7048632","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048632","url":null,"abstract":"This paper presents a new pulse width modulator dedicated basically for under determined systems. The solution of the under determined problem is performed by minimum 1-inflnity norm solution. One of known under determined system is a four-leg three-phase converter because four reference signals must be created from three control commands. The infinity norm enables to find proper solution to generate corresponding reference signals for the PWM modulator. The designed modulator is implemented with a control system of the four-leg three-phase converter working as an universal supply unit but the proposed modulator is able to operate in arbitrary application with the four-leg converter, generally for arbitrary under-deteremined systems. It is shown in the paper that the known carrier based PWM algorithm represents a subset of modulators utilizing the minimum 1-infinity norm. The theoretical assumptions and the design of the modulator were verified by simulations as well as by experiments on a laboratory prototype of 17 kVA.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121787504","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048863
Guillaume Demesure, M. Defoort, A. Bekrar, D. Trentesaux, M. Djemai
This paper provides a brief overview of recent cooperation mechanisms in multi-agent systems in order to establish a starting point for a new framework based on multi-agent systems in manufacturing systems and robotics. The relationships and possibilities of cross-fertilization between robotics and manufacturing systems are presented, and several issues concerning cooperation mechanisms introduced. A literature review is provided and some future prospects proposed.
{"title":"Cooperation mechanisms in multi-agent robotic systems and their use in distributed manufacturing control: Issues and literature review","authors":"Guillaume Demesure, M. Defoort, A. Bekrar, D. Trentesaux, M. Djemai","doi":"10.1109/IECON.2014.7048863","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048863","url":null,"abstract":"This paper provides a brief overview of recent cooperation mechanisms in multi-agent systems in order to establish a starting point for a new framework based on multi-agent systems in manufacturing systems and robotics. The relationships and possibilities of cross-fertilization between robotics and manufacturing systems are presented, and several issues concerning cooperation mechanisms introduced. A literature review is provided and some future prospects proposed.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132071721","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048908
Akihito Ito, N. Tsujiuchi, Yusuke Okada, R. Kojima
Recently, autonomous robots have been widely used in the production field. There are several advantages to introducing industrial robots in factories. However, these robots cannot be used in unknown environments because most of them are controlled by sequence controls. Two cameras are used as vision sensors that can recognize the outside environment to solve this problem. In this study, we aim at improving the camera calibration accuracies by two cameras. We know that calibration accuracies are affected by the positions of two cameras. Thus, we focus on the positions of the two cameras. Reducing the floor area of an industrial robot is expected to improve productivity. Thus, in this research, we propose the positions of two cameras in a small area by taking into consideration calibration accuracies. First of all, we examine the influences of the positions of two cameras for calibration accuracies. Next, we determine the optimal camera position from a simulation based on the modeling image noise obtained by experimentation. Finally, we verify the effectiveness of the positions of two cameras by a sorting operation. As a result, we can model the image noises of two cameras mathematically and determine the positions of the two cameras. Also, we can decrease the ranges of the cameras by 79.8%. In addition, the new camera positions improved the identification performance and handling performance.
{"title":"Multipurpose optimization of camera position for robot vision by considering calibration accuracy","authors":"Akihito Ito, N. Tsujiuchi, Yusuke Okada, R. Kojima","doi":"10.1109/IECON.2014.7048908","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048908","url":null,"abstract":"Recently, autonomous robots have been widely used in the production field. There are several advantages to introducing industrial robots in factories. However, these robots cannot be used in unknown environments because most of them are controlled by sequence controls. Two cameras are used as vision sensors that can recognize the outside environment to solve this problem. In this study, we aim at improving the camera calibration accuracies by two cameras. We know that calibration accuracies are affected by the positions of two cameras. Thus, we focus on the positions of the two cameras. Reducing the floor area of an industrial robot is expected to improve productivity. Thus, in this research, we propose the positions of two cameras in a small area by taking into consideration calibration accuracies. First of all, we examine the influences of the positions of two cameras for calibration accuracies. Next, we determine the optimal camera position from a simulation based on the modeling image noise obtained by experimentation. Finally, we verify the effectiveness of the positions of two cameras by a sorting operation. As a result, we can model the image noises of two cameras mathematically and determine the positions of the two cameras. Also, we can decrease the ranges of the cameras by 79.8%. In addition, the new camera positions improved the identification performance and handling performance.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132229360","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048889
Wenchao Gao, Wenyu Liang, K. Tan
Otitis Media with Effusion, a common ear disease, occurs in adults and children when the middle ear is infected, resulting in accumulation of fluid in the middle ear space. The conventional treatment is to surgically insert a ventilation tube into the tympanic membrane (TM) to suction out the fluid. An office-based robotic device allowing fast tube insertion has been designed in an earlier work of the authors. However, as the malleus bone attaches to the inner surface of the TM, and this part of the membrane is thus to be avoided during the insertion process. The previous device requires manual manipulation to avoid hitting the malleus bone before tube insertion. To accomplish the procedure automatically, a switching control scheme using intelligent vision-servo and tactile sensing is proposed in this paper. The new device is able to guide the insertion channel to move effectively and intelligently in the ear canal. Pre-clinical tests on the pig ears verify the feasibility and efficacy of the proposed approach.
{"title":"Automated tube insertion on tympanic membrane based on vision-servo and tactile sensing","authors":"Wenchao Gao, Wenyu Liang, K. Tan","doi":"10.1109/IECON.2014.7048889","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048889","url":null,"abstract":"Otitis Media with Effusion, a common ear disease, occurs in adults and children when the middle ear is infected, resulting in accumulation of fluid in the middle ear space. The conventional treatment is to surgically insert a ventilation tube into the tympanic membrane (TM) to suction out the fluid. An office-based robotic device allowing fast tube insertion has been designed in an earlier work of the authors. However, as the malleus bone attaches to the inner surface of the TM, and this part of the membrane is thus to be avoided during the insertion process. The previous device requires manual manipulation to avoid hitting the malleus bone before tube insertion. To accomplish the procedure automatically, a switching control scheme using intelligent vision-servo and tactile sensing is proposed in this paper. The new device is able to guide the insertion channel to move effectively and intelligently in the ear canal. Pre-clinical tests on the pig ears verify the feasibility and efficacy of the proposed approach.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130268041","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048688
R. Scapini, C. Rech, Tiago B. Marchesati, L. Schuch, R. F. Camargo, L. Michels
This paper presents a single-phase voltage distribution static synchronous compensator which integrates a single-phase to three-phase four-wired transformer-less conversion. Beyond that, this structure are capable to interface a distributed alternative energy generation to the mains. The major advantage of this circuit is the combined operation capability, which is realized with a few switching components while preserve an interconnected grounded neutral from mains to three-phase terminals. The power electronic circuit is parallel connected to the single-phase grid and add two additional terminals, which together, form the three-phase four-wired grid. The resulting active power from the converter energy balance are absorbed/delivered from/to the mains while the reactive power are managed to provide its single-phase voltage compensation. The power system scheme as well as the proposed closed-loop control structure are presented in details. Simulation results are illustrated to validate the converter assembly.
{"title":"Distribution STATCOM integrated to a single-phase to three-phase converter","authors":"R. Scapini, C. Rech, Tiago B. Marchesati, L. Schuch, R. F. Camargo, L. Michels","doi":"10.1109/IECON.2014.7048688","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048688","url":null,"abstract":"This paper presents a single-phase voltage distribution static synchronous compensator which integrates a single-phase to three-phase four-wired transformer-less conversion. Beyond that, this structure are capable to interface a distributed alternative energy generation to the mains. The major advantage of this circuit is the combined operation capability, which is realized with a few switching components while preserve an interconnected grounded neutral from mains to three-phase terminals. The power electronic circuit is parallel connected to the single-phase grid and add two additional terminals, which together, form the three-phase four-wired grid. The resulting active power from the converter energy balance are absorbed/delivered from/to the mains while the reactive power are managed to provide its single-phase voltage compensation. The power system scheme as well as the proposed closed-loop control structure are presented in details. Simulation results are illustrated to validate the converter assembly.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"112 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134193436","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048984
P. Szcześniak, J. Kaniewski
This paper deals with a voltage regulator based on a hybrid transformer with matrix converter realizing an electrical coupling in the hybrid transformer unit. The parameters of electrical energy such as voltage amplitude are very important, particularly from the viewpoint of the final consumer and sensitive loads connected to the grid. Furthermore, a hybrid transformer using matrix converter can be used for power flow control and for transient stability improvement in AC transmission systems. Active power flow and voltage magnitude in transmission lines can be varied using a conventional or thyristor controlled regulators. However, the control parameters can be executed only in steps depending on the taps available in the transformer. An approach for obtaining continuous control of the voltage magnitude and phase shift using a conventional transformer with two windings and a pulse width modulated matrix converter is presented in this paper. The operating principles and steady state properties are discussed. Detailed computer simulation results are presented in the paper. Furthermore, experimental test results obtained from a three-phase 3 kVA laboratory model with passive load are also presented.
{"title":"A voltage regulator/conditioner based on a hybrid transformer with matrix converter","authors":"P. Szcześniak, J. Kaniewski","doi":"10.1109/IECON.2014.7048984","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048984","url":null,"abstract":"This paper deals with a voltage regulator based on a hybrid transformer with matrix converter realizing an electrical coupling in the hybrid transformer unit. The parameters of electrical energy such as voltage amplitude are very important, particularly from the viewpoint of the final consumer and sensitive loads connected to the grid. Furthermore, a hybrid transformer using matrix converter can be used for power flow control and for transient stability improvement in AC transmission systems. Active power flow and voltage magnitude in transmission lines can be varied using a conventional or thyristor controlled regulators. However, the control parameters can be executed only in steps depending on the taps available in the transformer. An approach for obtaining continuous control of the voltage magnitude and phase shift using a conventional transformer with two windings and a pulse width modulated matrix converter is presented in this paper. The operating principles and steady state properties are discussed. Detailed computer simulation results are presented in the paper. Furthermore, experimental test results obtained from a three-phase 3 kVA laboratory model with passive load are also presented.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"29 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134258314","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048869
M. Wollschlaeger, R. Schrieber, Manfred Ullemeyer
The time in use of automation and control systems is typically much longer than technology development cycles. This is especially true with respect to the ongoing integration of IT technologies. In order to ensure the usage of automation systems during their planned time in use, the evolution of such systems need to be considered. This demands for generic models for handling life-cycle related information, and for suitable strategies to manage the life cycles of automation systems and their components. The paper discusses requirements from different industries, presents models for life cycle information and for managing compatibility throughout long periods. Finally, different strategies for life-cycle-management are described and a short outlook to standardization of the models is given.
{"title":"Life-cycle-management in automation-models and strategies","authors":"M. Wollschlaeger, R. Schrieber, Manfred Ullemeyer","doi":"10.1109/IECON.2014.7048869","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048869","url":null,"abstract":"The time in use of automation and control systems is typically much longer than technology development cycles. This is especially true with respect to the ongoing integration of IT technologies. In order to ensure the usage of automation systems during their planned time in use, the evolution of such systems need to be considered. This demands for generic models for handling life-cycle related information, and for suitable strategies to manage the life cycles of automation systems and their components. The paper discusses requirements from different industries, presents models for life cycle information and for managing compatibility throughout long periods. Finally, different strategies for life-cycle-management are described and a short outlook to standardization of the models is given.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134534722","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048813
A. Pigazo, Holger Jedtberg, Marco Liserre
Transformerless (TL) topologies are employed in 1φ PV inverter topologies due to their small size and low weight. Avoiding the grid side transformer requires the modulation technique and the basis topology to be accordingly changed in order to mitigate dc current components in the grid side and the leakage current to ground. This paper carries out a sensitivity analysis of selected TL topologies. This analysis investigates the impact of parameter variations of the employed semiconductor devices and detects the device which affects the most the overall efficiency. As a result, relevant info for engineers selecting the most suitable power devices for the implementation of a certain TL topology is provided.
{"title":"Sensitivity analysis of transformerless PV inverter topologies to physical variations of power devices","authors":"A. Pigazo, Holger Jedtberg, Marco Liserre","doi":"10.1109/IECON.2014.7048813","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048813","url":null,"abstract":"Transformerless (TL) topologies are employed in 1φ PV inverter topologies due to their small size and low weight. Avoiding the grid side transformer requires the modulation technique and the basis topology to be accordingly changed in order to mitigate dc current components in the grid side and the leakage current to ground. This paper carries out a sensitivity analysis of selected TL topologies. This analysis investigates the impact of parameter variations of the employed semiconductor devices and detects the device which affects the most the overall efficiency. As a result, relevant info for engineers selecting the most suitable power devices for the implementation of a certain TL topology is provided.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"55 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131515557","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 : 2014-10-01DOI: 10.1109/IECON.2014.7049165
Zhe Zhu, Xiaolin Li, H. Rao, Weihua Wang, Wei Li
This paper presents the dynamic performance test of a complete control and protection system for a Multi-terminal MMC HVDC system using hardware-in-the-loop (HIL) simulation. A novel HIL bench with a cost-effective input and output interface between the control system under test and the real-time simulator is introduced. Two critical test cases, namely the start-up of the MMC connected to islanded networks and the AC fault in the bus close to the MMC substation are studied. The validity of the proposed methodology for the dynamic performance test is confirmed by comparing the results from the HIL test and the actual waveform recorded from the field, after the MMC is commissioned.
{"title":"Testing a complete control and protection system for multi-terminal MMC HVDC links using hardware-in-the-loop simulation","authors":"Zhe Zhu, Xiaolin Li, H. Rao, Weihua Wang, Wei Li","doi":"10.1109/IECON.2014.7049165","DOIUrl":"https://doi.org/10.1109/IECON.2014.7049165","url":null,"abstract":"This paper presents the dynamic performance test of a complete control and protection system for a Multi-terminal MMC HVDC system using hardware-in-the-loop (HIL) simulation. A novel HIL bench with a cost-effective input and output interface between the control system under test and the real-time simulator is introduced. Two critical test cases, namely the start-up of the MMC connected to islanded networks and the AC fault in the bus close to the MMC substation are studied. The validity of the proposed methodology for the dynamic performance test is confirmed by comparing the results from the HIL test and the actual waveform recorded from the field, after the MMC is commissioned.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132638490","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 : 2014-10-01DOI: 10.1109/IECON.2014.7048568
M. Schael, C. Sourkounis
Technical processes, such as the shredder process, require a high power quality of the supplying electric grid for proper function. Especially variations of the supply voltage at the point of connection can lead to consequences from a diminished process and output quality to an interruption of the entire technical process. These effects are evaluated for an induction machine driven shredder system. Sources and general implications of voltage variations are presented and the shredder system model is introduced in detail. The results show direct influences of voltage variations on the shredding process.
{"title":"Impact of voltage variations on a grid-connected shredder system","authors":"M. Schael, C. Sourkounis","doi":"10.1109/IECON.2014.7048568","DOIUrl":"https://doi.org/10.1109/IECON.2014.7048568","url":null,"abstract":"Technical processes, such as the shredder process, require a high power quality of the supplying electric grid for proper function. Especially variations of the supply voltage at the point of connection can lead to consequences from a diminished process and output quality to an interruption of the entire technical process. These effects are evaluated for an induction machine driven shredder system. Sources and general implications of voltage variations are presented and the shredder system model is introduced in detail. The results show direct influences of voltage variations on the shredding process.","PeriodicalId":228897,"journal":{"name":"IECON 2014 - 40th Annual Conference of the IEEE Industrial Electronics Society","volume":"157 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132641120","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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