Pub Date : 2014-12-08DOI: 10.1109/IAS.2014.6978461
Liang Zhang, Xiaosheng Liu, Dianguo Xu
This paper presents a novel security monitoring system of mine based on power line communication; with networking and routing technology, an artificial cobweb routing of security monitoring communication system is established to ensure the reliability of data communication in the system, and improve the reliability and validity of the PLC-based security monitoring system. This paper describes in detail the overall hardware and software framework of the system, the design communication terminal nodes, the mine communication network model and network structure based on artificial cobweb. The experiment results about the delay and throughput show that this system can achieve real-time monitoring of underground mines, sound and light alarm and two-way data communication with the control center on the ground, providing new ideas and guiding methods for mine security monitoring system design and development.
{"title":"A novel security monitoring system of coal mine based on power line communication dynamic routing technology","authors":"Liang Zhang, Xiaosheng Liu, Dianguo Xu","doi":"10.1109/IAS.2014.6978461","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978461","url":null,"abstract":"This paper presents a novel security monitoring system of mine based on power line communication; with networking and routing technology, an artificial cobweb routing of security monitoring communication system is established to ensure the reliability of data communication in the system, and improve the reliability and validity of the PLC-based security monitoring system. This paper describes in detail the overall hardware and software framework of the system, the design communication terminal nodes, the mine communication network model and network structure based on artificial cobweb. The experiment results about the delay and throughput show that this system can achieve real-time monitoring of underground mines, sound and light alarm and two-way data communication with the control center on the ground, providing new ideas and guiding methods for mine security monitoring system design and development.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"13 5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133837393","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978372
Shunsuke Sakae, A. Takahashi, J. Imai, S. Funabiki
This paper proposes a novel energy management method for distributed generation systems using a fuel cell vehicle and photovoltaic cells and validates the usefulness of the proposed energy management method. The proposed method can be used not only in normal daily operation but also in emergency operation. In the normal daily operation, the utility grid can supply power to the domestic power load. The proposed method is evaluated on the basis of the reduction rate in power fluctuation and operating cost per day. On the other hand, the utility grid cannot supply power to the domestic power load during the emergency operation. Thus, the proposed method is evaluated by the number of operative days. As a result, the proposed method reduces 40% of the power fluctuation, and the operating cost in the normal daily operation become cheaper. In the emergency operation, the proposed system can operate until electricity is restored.
{"title":"Energy management method for residential distributed generation system using photovoltaic cells and fuel cell vehicle","authors":"Shunsuke Sakae, A. Takahashi, J. Imai, S. Funabiki","doi":"10.1109/IAS.2014.6978372","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978372","url":null,"abstract":"This paper proposes a novel energy management method for distributed generation systems using a fuel cell vehicle and photovoltaic cells and validates the usefulness of the proposed energy management method. The proposed method can be used not only in normal daily operation but also in emergency operation. In the normal daily operation, the utility grid can supply power to the domestic power load. The proposed method is evaluated on the basis of the reduction rate in power fluctuation and operating cost per day. On the other hand, the utility grid cannot supply power to the domestic power load during the emergency operation. Thus, the proposed method is evaluated by the number of operative days. As a result, the proposed method reduces 40% of the power fluctuation, and the operating cost in the normal daily operation become cheaper. In the emergency operation, the proposed system can operate until electricity is restored.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"54 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133852237","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978426
L. Kukačka, P. Dupuis, Rikardo Simanjuntak, G. Zissis
This paper addresses the problematic of usage of electronic ballasts in modern LED lighting equipment. A sample of eleven LED lamps available on the market is analyzed in temporal and frequency based analysis. The topology of the ballasts is determined and modeled using Spice software in a simplified manner. Results of the simulations are verified. Pairs of the lamp models are simulated and compared to original waveforms.
{"title":"Simplified models of LED ballasts for spice","authors":"L. Kukačka, P. Dupuis, Rikardo Simanjuntak, G. Zissis","doi":"10.1109/IAS.2014.6978426","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978426","url":null,"abstract":"This paper addresses the problematic of usage of electronic ballasts in modern LED lighting equipment. A sample of eleven LED lamps available on the market is analyzed in temporal and frequency based analysis. The topology of the ballasts is determined and modeled using Spice software in a simplified manner. Results of the simulations are verified. Pairs of the lamp models are simulated and compared to original waveforms.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114830345","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978488
Jesus Jativa-Ibarra, Gabriela Navarro-Mendez, F. Quilumba, Weijen Lee
Due to problems caused by non-linear loads in a power system, a harmonic technical analysis on the hydroelectric generating units Illuchi 1 and 2 of the Electric Utility Company of Cotopaxi Province ELEPCO S.A., Ecuador, is performed in this project by means of industrial analyzers as well as software simulation. The analysis starts from harmonic distortion measurements on the generating plants and El Calvario substation. Then, simulations are performed including non-linear loads characterized as current sources in the east zone of the studied system by using a harmonic power flow to determine the industrial load causing the current fluctuations. The maximum values of THD are in the order of 5.4% and 3% in Illuchi 1 and 2, respectively, that are above the recommended values of IEEE Std. 519-1992. Based on these results and determined the cause, filters for 5th and 7th harmonic according to the IEEE Std. 1531-2003 are designed.
{"title":"Field measurements, modeling, and analysis of power system harmonics caused by industrial customers","authors":"Jesus Jativa-Ibarra, Gabriela Navarro-Mendez, F. Quilumba, Weijen Lee","doi":"10.1109/IAS.2014.6978488","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978488","url":null,"abstract":"Due to problems caused by non-linear loads in a power system, a harmonic technical analysis on the hydroelectric generating units Illuchi 1 and 2 of the Electric Utility Company of Cotopaxi Province ELEPCO S.A., Ecuador, is performed in this project by means of industrial analyzers as well as software simulation. The analysis starts from harmonic distortion measurements on the generating plants and El Calvario substation. Then, simulations are performed including non-linear loads characterized as current sources in the east zone of the studied system by using a harmonic power flow to determine the industrial load causing the current fluctuations. The maximum values of THD are in the order of 5.4% and 3% in Illuchi 1 and 2, respectively, that are above the recommended values of IEEE Std. 519-1992. Based on these results and determined the cause, filters for 5th and 7th harmonic according to the IEEE Std. 1531-2003 are designed.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116799463","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978393
Y. Kubo, T. Moroi, K. Matsuse, H. Kubota, K. Rajashekara
This paper presents the experimental results of the independent rated speed control of two induction motors (IMs) fed by a four-leg inverter (4LI) with field-weakening control method. The inverter consists of four legs and two capacitors connected in a series. The 4LI have several disadvantages. First, it is not possible to modulate W phase voltage of the IMs. Second, the neutral point potential of two capacitors fluctuates. Third, motors speed does not come up to the rated speed. This paper shows an expanded two-arm modulation, compensation method and field-weakening control method to solve them. Next, the independent rated speed control of two IMs fed by the 4LI with the field-weakening control system is demonstrated by the experimental results. Moreover, it shows the effectiveness of those methods.
{"title":"Independent rated speed control of two induction motors fed by a four-leg inverter","authors":"Y. Kubo, T. Moroi, K. Matsuse, H. Kubota, K. Rajashekara","doi":"10.1109/IAS.2014.6978393","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978393","url":null,"abstract":"This paper presents the experimental results of the independent rated speed control of two induction motors (IMs) fed by a four-leg inverter (4LI) with field-weakening control method. The inverter consists of four legs and two capacitors connected in a series. The 4LI have several disadvantages. First, it is not possible to modulate W phase voltage of the IMs. Second, the neutral point potential of two capacitors fluctuates. Third, motors speed does not come up to the rated speed. This paper shows an expanded two-arm modulation, compensation method and field-weakening control method to solve them. Next, the independent rated speed control of two IMs fed by the 4LI with the field-weakening control system is demonstrated by the experimental results. Moreover, it shows the effectiveness of those methods.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130173164","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978353
M. Miloudi, L. Dascalescu, Jia Li, K. Medles, A. Tilmatine
The two-conveyor-electrodes tribo-aero-electrostatic separator patented in 2010 was designed to sort granular mixtures of insulating materials in a fluidized bed subjected to an electric field perpendicular to the direction of the fluidizing air. The prototype ≤has proven its efficiency for the separation of insulating granules ≤ 2 mm, attaining excellent recovery rates. Its performances were less satisfactory for larger particles (2 to 4.5 mm). The objective of this work is to evaluate three modifications of the construction of this device, in order to increase the hourly throughput and improve the purity of the products, by controlling the charge acquired by the granules and the electric field intensity. Numerical simulations enabled the optimization of the electric field distribution in the active zone of the separator and an experimental study was carried out in order to identify the best conditions for granule charging by triboelectric effect. The tests were carried out for four configurations of the electrode system, by using a mixture of acrylonitrile butadiene styrene (ABS) and high impact polystyrene (HIPS) originated from grinding out-of-use computer cases. The typical granule size was 2 to 4.5 mm. The experimental approach validated a change in the position of the fluidized bed with respect to the conveyor electrodes, to increase the residence time of the granular materials and hence the amount of electric charge acquired by each particle. In order to intensify the electrical field, two solutions were tested and validated: (1) add a grounding electrode in the proximity of the high-voltage electrodes; (2) dispose vertically the high voltage electrodes. For the tested materials, the vertical arrangement of the electrodes gave the best hourly throughput rates and purity of the separated products.
{"title":"Performance improvement of a separator tribo-electrostatic aero for granular materials plastics recycling of waste electrical and electronic equipment","authors":"M. Miloudi, L. Dascalescu, Jia Li, K. Medles, A. Tilmatine","doi":"10.1109/IAS.2014.6978353","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978353","url":null,"abstract":"The two-conveyor-electrodes tribo-aero-electrostatic separator patented in 2010 was designed to sort granular mixtures of insulating materials in a fluidized bed subjected to an electric field perpendicular to the direction of the fluidizing air. The prototype ≤has proven its efficiency for the separation of insulating granules ≤ 2 mm, attaining excellent recovery rates. Its performances were less satisfactory for larger particles (2 to 4.5 mm). The objective of this work is to evaluate three modifications of the construction of this device, in order to increase the hourly throughput and improve the purity of the products, by controlling the charge acquired by the granules and the electric field intensity. Numerical simulations enabled the optimization of the electric field distribution in the active zone of the separator and an experimental study was carried out in order to identify the best conditions for granule charging by triboelectric effect. The tests were carried out for four configurations of the electrode system, by using a mixture of acrylonitrile butadiene styrene (ABS) and high impact polystyrene (HIPS) originated from grinding out-of-use computer cases. The typical granule size was 2 to 4.5 mm. The experimental approach validated a change in the position of the fluidized bed with respect to the conveyor electrodes, to increase the residence time of the granular materials and hence the amount of electric charge acquired by each particle. In order to intensify the electrical field, two solutions were tested and validated: (1) add a grounding electrode in the proximity of the high-voltage electrodes; (2) dispose vertically the high voltage electrodes. For the tested materials, the vertical arrangement of the electrodes gave the best hourly throughput rates and purity of the separated products.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"40 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126574957","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978366
Sheng-Yen Lu, Li Wang, Te-Ming Lo
In order to study uncertainty and intermittent characteristics of wind power and wave power, this paper proposes an integrated wind- and wave-power generation system fed to a power grid or connected with an isolated load using a DC micro grid. The studied integrated system consists of a wind-power generator, a wave-power generator, a bidirectional DC/DC converter, and a grid-tied inverter. An energy-storage device is connected to the DC side of the proposed DC micro grid through a bi-directional DC/DC converter. Both wind-and wave-power generation systems are modeled and simulated using the written program based on MATLAB/Simulink. Steady-state and dynamic responses of the studied system under various operating conditions are carried out. To examine the fundamental operating characteristics of the proposed integrated system, a laboratory-scale platform is also established. The experimental results reveal that the studied integrated system can maintain stable operation to supply power under different operating conditions using the proposed DC micro grid.
{"title":"Integration of wind-power and wave-power generation systems using a DC micro grid","authors":"Sheng-Yen Lu, Li Wang, Te-Ming Lo","doi":"10.1109/IAS.2014.6978366","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978366","url":null,"abstract":"In order to study uncertainty and intermittent characteristics of wind power and wave power, this paper proposes an integrated wind- and wave-power generation system fed to a power grid or connected with an isolated load using a DC micro grid. The studied integrated system consists of a wind-power generator, a wave-power generator, a bidirectional DC/DC converter, and a grid-tied inverter. An energy-storage device is connected to the DC side of the proposed DC micro grid through a bi-directional DC/DC converter. Both wind-and wave-power generation systems are modeled and simulated using the written program based on MATLAB/Simulink. Steady-state and dynamic responses of the studied system under various operating conditions are carried out. To examine the fundamental operating characteristics of the proposed integrated system, a laboratory-scale platform is also established. The experimental results reveal that the studied integrated system can maintain stable operation to supply power under different operating conditions using the proposed DC micro grid.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"301 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122315379","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978425
W. Witt, A. Stankovic
This paper describes the various input variables of an LED system (electronic driver and LED), such as component behavior, tolerance, thermal effects, and manufacturing variability - which all contribute to important end-use system parameters such as watts and total lumen output. A mathematical model with probability functions is constructed in Microsoft Excel to compute electrical parameters. Sensitivity analysis and parameter forecasting is then performed via the Monte Carlo method, using the Crystal Ball add-on software package by Oracle. Forecasted results for power are then compared and verified against test results of mass production parts.
{"title":"Forecasting electrical parameters of mass-produced LED luminaire using the Monte Carlo method","authors":"W. Witt, A. Stankovic","doi":"10.1109/IAS.2014.6978425","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978425","url":null,"abstract":"This paper describes the various input variables of an LED system (electronic driver and LED), such as component behavior, tolerance, thermal effects, and manufacturing variability - which all contribute to important end-use system parameters such as watts and total lumen output. A mathematical model with probability functions is constructed in Microsoft Excel to compute electrical parameters. Sensitivity analysis and parameter forecasting is then performed via the Monte Carlo method, using the Crystal Ball add-on software package by Oracle. Forecasted results for power are then compared and verified against test results of mass production parts.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116053248","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978505
S. Saleh, A. Aljankawey, B. Alsayid, M. A. Khaizaran
Photovoltaic (PV) systems have become a popular type of distributed generation units (DGUs) for small and medium levels of renewable energy generation. These DGUs are designed and operated to deliver electric power through one or more stages of power electronic converters (PECs). The non-linear and switched natures, along with control actions, of PECs used in PV systems can be of major influences on current-voltage behaviors during faults. Such faults may take place on the PV system side or host grid side. This paper investigates the current-voltage behaviors in grid-connected PV systems during fault conditions.
{"title":"Influences of power electronic converters on current-voltage behaviors during faults in DGUs-Part II: Photovoltaic systems","authors":"S. Saleh, A. Aljankawey, B. Alsayid, M. A. Khaizaran","doi":"10.1109/IAS.2014.6978505","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978505","url":null,"abstract":"Photovoltaic (PV) systems have become a popular type of distributed generation units (DGUs) for small and medium levels of renewable energy generation. These DGUs are designed and operated to deliver electric power through one or more stages of power electronic converters (PECs). The non-linear and switched natures, along with control actions, of PECs used in PV systems can be of major influences on current-voltage behaviors during faults. Such faults may take place on the PV system side or host grid side. This paper investigates the current-voltage behaviors in grid-connected PV systems during fault conditions.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121456291","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 : 2014-12-08DOI: 10.1109/IAS.2014.6978385
Jingbo Liu, Takayoshi Matsuo, T. Nondahl, P. Schmidt, T. Rowan, Robert J. De Lange
In recent years there has been increasing acceptance of position sensorless control in industrial products. This paper discusses the implementation and performance of a position sensorless permanent magnet synchronous motor (PMSM) control over the full speed range in a PMSM drive. Experimental results with a commercial drive which utilizes a sensorless scheme are presented in the paper.
{"title":"Implementation and performance of position sensorless PMSM control in industrial drives","authors":"Jingbo Liu, Takayoshi Matsuo, T. Nondahl, P. Schmidt, T. Rowan, Robert J. De Lange","doi":"10.1109/IAS.2014.6978385","DOIUrl":"https://doi.org/10.1109/IAS.2014.6978385","url":null,"abstract":"In recent years there has been increasing acceptance of position sensorless control in industrial products. This paper discusses the implementation and performance of a position sensorless permanent magnet synchronous motor (PMSM) control over the full speed range in a PMSM drive. Experimental results with a commercial drive which utilizes a sensorless scheme are presented in the paper.","PeriodicalId":446068,"journal":{"name":"2014 IEEE Industry Application Society Annual Meeting","volume":"265 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-08","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122906086","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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