Pub Date : 2017-07-01DOI: 10.1109/EUROCON.2017.8011142
Muhammed Akif Ulker, B. Uzunoğlu
Intermittent renewable energy sources in distributed generation will increase the chance of sudden unpredictable changes in the system states and parameters of dynamic power systems. To track the changes of the power systems, system state and parameter estimation methods that can track the near real-time dynamics of the power systems are needed. Power system operators still employ simulation studies using off-line models that are built based on prior knowledge gained through information via simulated typical scenarios which does not make use of posterior knowledge of neither parameter space nor state space of the dynamics of the power systems. Dynamic models of a power system has increasingly more important role in power system operations since they impact the operational conditions of dynamical power system. In this study, we propose a particle filter based state and parameter estimation method to improve modelling accuracy, which determines the best set of model parameters using real-time measurement data. This can be achieved via measurements by Phasor Measurement Units (PMU) or Remote Terminal Units (RTU) that can capture the system dynamic responses in real time. In addition, parameters of the system can also be estimated. Herein the load will be the parameter of the system that needs to be estimated jointly with the states. Joint state and parameter estimation for power systems via employing Bayesian particle filter is being introduced in this study.
{"title":"Particle filter joint state and parameter estimation of dynamic power systems","authors":"Muhammed Akif Ulker, B. Uzunoğlu","doi":"10.1109/EUROCON.2017.8011142","DOIUrl":"https://doi.org/10.1109/EUROCON.2017.8011142","url":null,"abstract":"Intermittent renewable energy sources in distributed generation will increase the chance of sudden unpredictable changes in the system states and parameters of dynamic power systems. To track the changes of the power systems, system state and parameter estimation methods that can track the near real-time dynamics of the power systems are needed. Power system operators still employ simulation studies using off-line models that are built based on prior knowledge gained through information via simulated typical scenarios which does not make use of posterior knowledge of neither parameter space nor state space of the dynamics of the power systems. Dynamic models of a power system has increasingly more important role in power system operations since they impact the operational conditions of dynamical power system. In this study, we propose a particle filter based state and parameter estimation method to improve modelling accuracy, which determines the best set of model parameters using real-time measurement data. This can be achieved via measurements by Phasor Measurement Units (PMU) or Remote Terminal Units (RTU) that can capture the system dynamic responses in real time. In addition, parameters of the system can also be estimated. Herein the load will be the parameter of the system that needs to be estimated jointly with the states. Joint state and parameter estimation for power systems via employing Bayesian particle filter is being introduced in this study.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"52 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2017-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129367400","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 : 2016-11-30DOI: 10.1109/RTUCON.2016.7763142
Amjad Hussain, M. Shafiq, M. Lehtonen
Reliable operation of the switchgear is essential for delivery of electric power to the end users. Poor connections and insulation degradation are the two major causes of arc-flash in the switchgear. This paper evaluates the non-intrusive measurement and performance of thermal ionization detector (TID) in the low voltage (LV) air insulated switchgear. The sensitivity analysis of the sensor is done in comparison with thermocouples. Experimental investigation is performed in a climate controlled chamber where bus bars having poor joints are installed. Useful deductions based on measured results, have been discussed in this paper. This particular type of study is nonexistent in the literature. So, it will be remarkably helpful for the researcher and engineers working in the online condition monitoring area.
{"title":"Thermal monitoring of low voltage switchgear using thermal ionization detector","authors":"Amjad Hussain, M. Shafiq, M. Lehtonen","doi":"10.1109/RTUCON.2016.7763142","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763142","url":null,"abstract":"Reliable operation of the switchgear is essential for delivery of electric power to the end users. Poor connections and insulation degradation are the two major causes of arc-flash in the switchgear. This paper evaluates the non-intrusive measurement and performance of thermal ionization detector (TID) in the low voltage (LV) air insulated switchgear. The sensitivity analysis of the sensor is done in comparison with thermocouples. Experimental investigation is performed in a climate controlled chamber where bus bars having poor joints are installed. Useful deductions based on measured results, have been discussed in this paper. This particular type of study is nonexistent in the literature. So, it will be remarkably helpful for the researcher and engineers working in the online condition monitoring area.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134165716","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 : 2016-11-30DOI: 10.1109/RTUCON.2016.7763127
A. Rassõlkin, S. Orlova, T. Vaimann, A. Belahcen, A. Kallaste
This paper presents an analysis of the environmental and life cycle costs of a synchronous reluctance machine (SynRM). Focusing exceptionally on consumption is no longer sufficient, energy savings initiatives must now account for all life cycle assessment (LCA), including construction, use and end-of-life. The analysis was carried out according to the Energy-Using Product Directive (EuP 2005/32/EC) and following the Methodology for the Eco-Design of Energy-Using Products (MEEUP methodology).
{"title":"Environmental and life cycle cost analysis of a synchronous reluctance machine","authors":"A. Rassõlkin, S. Orlova, T. Vaimann, A. Belahcen, A. Kallaste","doi":"10.1109/RTUCON.2016.7763127","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763127","url":null,"abstract":"This paper presents an analysis of the environmental and life cycle costs of a synchronous reluctance machine (SynRM). Focusing exceptionally on consumption is no longer sufficient, energy savings initiatives must now account for all life cycle assessment (LCA), including construction, use and end-of-life. The analysis was carried out according to the Energy-Using Product Directive (EuP 2005/32/EC) and following the Methodology for the Eco-Design of Energy-Using Products (MEEUP methodology).","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"82 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-11-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115015202","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 : 2016-10-01DOI: 10.1109/RTUCON.2016.7763154
I. Bolgov, V. Bolgova
Due to the modern techniques and technologies development a thorough attention on simulation of autonomous variable frequency systems is paid. The advantage of the electric machine taken as a basis for this modeling leaves no doubt for use it in aggressive environments. The designed model of a two-phase brushless DC electric motor is specifically designed to be connected to a model of PWM inverter, describes the processes occurring in the motor, and also allows to simulate abnormal situations to predict possible failures. The study was carried out by building a simulation model in the programming environment Matlab Simulink.
{"title":"Detailed simulation model of the two-phase brushless DC motor designed for VFD integration","authors":"I. Bolgov, V. Bolgova","doi":"10.1109/RTUCON.2016.7763154","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763154","url":null,"abstract":"Due to the modern techniques and technologies development a thorough attention on simulation of autonomous variable frequency systems is paid. The advantage of the electric machine taken as a basis for this modeling leaves no doubt for use it in aggressive environments. The designed model of a two-phase brushless DC electric motor is specifically designed to be connected to a model of PWM inverter, describes the processes occurring in the motor, and also allows to simulate abnormal situations to predict possible failures. The study was carried out by building a simulation model in the programming environment Matlab Simulink.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114674095","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 : 2016-10-01DOI: 10.1109/RTUCON.2016.7763156
A. Pumpurs, L. Ribickis
This paper describes the use of smart materials and adaptronic control concepts in small size robots. Small size in this specific research means that robot hand have the span from several centimeters to some tens of centimeters. The possibility of building robot mechanics using different kind of smart materials are analyzed. There is no target to build the specific robot, but the possible solutions are analyzed. The control method for SMA (Shape Memory Alloy) actuator is proposed. The method for estimating temperature inside the SMA sample is described. The experimental setup is built up and the test measurements are made. The dynamics of control and the energy consumption of proposed control method are analyzed.
{"title":"The control of smart material based actuators for industrial robots","authors":"A. Pumpurs, L. Ribickis","doi":"10.1109/RTUCON.2016.7763156","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763156","url":null,"abstract":"This paper describes the use of smart materials and adaptronic control concepts in small size robots. Small size in this specific research means that robot hand have the span from several centimeters to some tens of centimeters. The possibility of building robot mechanics using different kind of smart materials are analyzed. There is no target to build the specific robot, but the possible solutions are analyzed. The control method for SMA (Shape Memory Alloy) actuator is proposed. The method for estimating temperature inside the SMA sample is described. The experimental setup is built up and the test measurements are made. The dynamics of control and the energy consumption of proposed control method are analyzed.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127098250","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 : 2016-10-01DOI: 10.1109/RTUCON.2016.7763086
L. Gevorkov, V. Vodovozov, Z. Raud
In this paper, the simulation environment is proposed that enables accurate full-scale investigation of the pressure adjustment for a centrifugal pump. The novel Matlab model is described, the pumping control procedure is explained, and the simulation results are assessed with the help of an experimental pumping test bench. Basing on thorough inspection of the developed software, the offered toolbox can be considered as a sensible tool for finding optimal pressure adjustment potential at high-quality pumping.
{"title":"Simulation study of the pressure control system for a centrifugal pump","authors":"L. Gevorkov, V. Vodovozov, Z. Raud","doi":"10.1109/RTUCON.2016.7763086","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763086","url":null,"abstract":"In this paper, the simulation environment is proposed that enables accurate full-scale investigation of the pressure adjustment for a centrifugal pump. The novel Matlab model is described, the pumping control procedure is explained, and the simulation results are assessed with the help of an experimental pumping test bench. Basing on thorough inspection of the developed software, the offered toolbox can be considered as a sensible tool for finding optimal pressure adjustment potential at high-quality pumping.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126044974","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 : 2016-10-01DOI: 10.1109/RTUCON.2016.7763117
F. Casesnoves, M. Antonov, P. Kulu
Surface damage in power plants causes economic loss and waste of operational time in modifications or repair. The wear is caused mainly by solid particles and water droplets. Erosion and corrosion of protective coatings constitute a number of significant engineering difficulties. “Trial and error” type methodology to improve the materials design is rather expensive, inaccurate and time consuming. Mathematical modelling through optimization methods overcome these engineering complications/difficulties, and reduce the experimental/tribotesting period. In this paper we provide a brief review of the current classified erosion and/or corrosion models and, additionally, detailed modern optimization methods for precise modelling of given applications. A concise computational optimization example for an erosion model is presented with brief software details/approximations.
{"title":"Mathematical models for erosion and corrosion in power plants. A review of applicable modelling optimization techniques","authors":"F. Casesnoves, M. Antonov, P. Kulu","doi":"10.1109/RTUCON.2016.7763117","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763117","url":null,"abstract":"Surface damage in power plants causes economic loss and waste of operational time in modifications or repair. The wear is caused mainly by solid particles and water droplets. Erosion and corrosion of protective coatings constitute a number of significant engineering difficulties. “Trial and error” type methodology to improve the materials design is rather expensive, inaccurate and time consuming. Mathematical modelling through optimization methods overcome these engineering complications/difficulties, and reduce the experimental/tribotesting period. In this paper we provide a brief review of the current classified erosion and/or corrosion models and, additionally, detailed modern optimization methods for precise modelling of given applications. A concise computational optimization example for an erosion model is presented with brief software details/approximations.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115052077","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 : 2016-10-01DOI: 10.1109/RTUCON.2016.7763146
E. Votyakova, A. Gnatyuk, B. Staroverov
The article presents the idea of using expert evaluation methods for choosing power substations equipment. The article suggests using analytic hierarchy process as the most convenient for such type of complex task solving. Direct analytic hierarchy process is represented as an improvement over the traditional method developed by Thomas L. Saaty. It simplifies analytic hierarchy process by getting weights of the criteria and alternatives without pair-comparison matrix forming.
提出了采用专家评价方法进行变电站设备选择的思路。本文建议使用层次分析法作为最方便的方法来解决这类复杂任务。直接层次分析法是对Thomas L. Saaty开发的传统方法的改进。该方法在不形成对比较矩阵的情况下，通过得到准则和备选方案的权重，简化了层次分析过程。
{"title":"Direct analytic hierarchy process for choosing power substation equipment","authors":"E. Votyakova, A. Gnatyuk, B. Staroverov","doi":"10.1109/RTUCON.2016.7763146","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763146","url":null,"abstract":"The article presents the idea of using expert evaluation methods for choosing power substations equipment. The article suggests using analytic hierarchy process as the most convenient for such type of complex task solving. Direct analytic hierarchy process is represented as an improvement over the traditional method developed by Thomas L. Saaty. It simplifies analytic hierarchy process by getting weights of the criteria and alternatives without pair-comparison matrix forming.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"121 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122942715","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 : 2016-10-01DOI: 10.1109/RTUCON.2016.7763137
G. Altintas, M. O. Gulbahce, D. Kocabas
In this study, a practical boost converter which includes nonidealities is analysed. Nonidealities are considered such as voltage drop of capacitor equivalent resistor and inductor series resistor and diode forward voltage drop. Steady state analysis and small signal modelling is derived. Control restrictions caused by “right half plane zero in continuous conduction mode operated boost converter” is explained and a PI control technique is proposed to reduce undesired effects. Moreover, open loop and closed loop characteristics of implemented boost converter are obtained.
{"title":"Nonideal analysis, design and voltage mode control of a boost converter","authors":"G. Altintas, M. O. Gulbahce, D. Kocabas","doi":"10.1109/RTUCON.2016.7763137","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763137","url":null,"abstract":"In this study, a practical boost converter which includes nonidealities is analysed. Nonidealities are considered such as voltage drop of capacitor equivalent resistor and inductor series resistor and diode forward voltage drop. Steady state analysis and small signal modelling is derived. Control restrictions caused by “right half plane zero in continuous conduction mode operated boost converter” is explained and a PI control technique is proposed to reduce undesired effects. Moreover, open loop and closed loop characteristics of implemented boost converter are obtained.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116318925","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 : 2016-10-01DOI: 10.1109/RTUCON.2016.7763144
T. Koppel, Heldur Haldre, A. Shishkin, I. Hussainova, N. Toropovs, V. Mironovs, P. Tint
Controlling exposure to the electromagnetic fields (EMFs) may serve many causes: to protect sensitive electronic equipment from outside interference; to protect the environment from the high radiation generating equipment; to protect humans from excess radiation etc. Strong EMFs may be encountered in public domain but especially in occupational settings, where the process and technology of work requires the EMFs. Technical measures to manage risks may include using construction materials. In this study the intermediate and low radiofrequency transmission characteristics in case of building materials were investigated. The measurements are called for to determine the amplitude of the electric and magnetic field at the close proximity to the material. A set of common building materials was selected, widely used in modern constructions. The included materials can broadly be divided into three groups: load bearing materials, thermal insulation materials and cover materials. Altogether 17 building materials were tested, forming an overview of some most common materials in construction of houses. The testing was done at 2, 20 and 200 kHz frequencies. The measurement point was in close proximity (10mm) to the material under testing. The electromagnetic irradiator point was on the other side of the material, 150 mm from the measurement sensor. Somewhat frequency dependent variation in the amplification could be observed only in few cases: gypsum panel, aerated concrete, LECA, gypsum board and solid wood. The highest electric field amplification was measured for some materials, up to 5.6 dB increase: custom made gypsum panel, aerated concrete, LECA, gypsum board, high performance concrete plate, solid wood. The results show for the selected samples that semiconductive materials which cannot be grounded due to the high resistance, electric fields may be amplified several folds in close proximity to the material.
{"title":"Intermediate and low radiofrequency electromagnetic field transmission properties in case of common building materials","authors":"T. Koppel, Heldur Haldre, A. Shishkin, I. Hussainova, N. Toropovs, V. Mironovs, P. Tint","doi":"10.1109/RTUCON.2016.7763144","DOIUrl":"https://doi.org/10.1109/RTUCON.2016.7763144","url":null,"abstract":"Controlling exposure to the electromagnetic fields (EMFs) may serve many causes: to protect sensitive electronic equipment from outside interference; to protect the environment from the high radiation generating equipment; to protect humans from excess radiation etc. Strong EMFs may be encountered in public domain but especially in occupational settings, where the process and technology of work requires the EMFs. Technical measures to manage risks may include using construction materials. In this study the intermediate and low radiofrequency transmission characteristics in case of building materials were investigated. The measurements are called for to determine the amplitude of the electric and magnetic field at the close proximity to the material. A set of common building materials was selected, widely used in modern constructions. The included materials can broadly be divided into three groups: load bearing materials, thermal insulation materials and cover materials. Altogether 17 building materials were tested, forming an overview of some most common materials in construction of houses. The testing was done at 2, 20 and 200 kHz frequencies. The measurement point was in close proximity (10mm) to the material under testing. The electromagnetic irradiator point was on the other side of the material, 150 mm from the measurement sensor. Somewhat frequency dependent variation in the amplification could be observed only in few cases: gypsum panel, aerated concrete, LECA, gypsum board and solid wood. The highest electric field amplification was measured for some materials, up to 5.6 dB increase: custom made gypsum panel, aerated concrete, LECA, gypsum board, high performance concrete plate, solid wood. The results show for the selected samples that semiconductive materials which cannot be grounded due to the high resistance, electric fields may be amplified several folds in close proximity to the material.","PeriodicalId":102691,"journal":{"name":"2016 57th International Scientific Conference on Power and Electrical Engineering of Riga Technical University (RTUCON)","volume":"8 8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2016-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130479119","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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