Pub Date : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526103
D. Gross
Generally, power engineering equipment is not designed to nicely transmit high frequency signals as used for partial discharge measurement and monitoring. For distributed equipment, such as transformers or rotating machines, the related effects, such as dispersion, attenuation, reflection, etc. already hamper partial discharge measurements in the frequency range of the IEC60270. Onsite measurements and monitoring often require using higher frequencies, where these effects have an even higher impact. This paper describes the different effects and their impact on measurement techniques.
{"title":"Partial discharge signal transmission of distributed power engineering equipment","authors":"D. Gross","doi":"10.1109/DIAGNOSTIKA.2018.8526103","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526103","url":null,"abstract":"Generally, power engineering equipment is not designed to nicely transmit high frequency signals as used for partial discharge measurement and monitoring. For distributed equipment, such as transformers or rotating machines, the related effects, such as dispersion, attenuation, reflection, etc. already hamper partial discharge measurements in the frequency range of the IEC60270. Onsite measurements and monitoring often require using higher frequencies, where these effects have an even higher impact. This paper describes the different effects and their impact on measurement techniques.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129301168","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526118
A. Stoynova
A new approach and experimental results on infrared thermographic inspection of relays used in rail automation are presented. The purpose of the research is to conduct inspection and evaluation of the contact system in real working conditions without disconnecting the relays from the circuit and without removing their protective cover. For this purpose, an algorithm has been developed for digital thermograms analising and temperature information deriving at pixel level. The results obtained from the application of the method can be used to evaluate the relay residual life as well as to make early diagnostics of defects due to the contact wearing out.
{"title":"Infrared Thermography Inspection for Safer Rail Transport Automation","authors":"A. Stoynova","doi":"10.1109/DIAGNOSTIKA.2018.8526118","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526118","url":null,"abstract":"A new approach and experimental results on infrared thermographic inspection of relays used in rail automation are presented. The purpose of the research is to conduct inspection and evaluation of the contact system in real working conditions without disconnecting the relays from the circuit and without removing their protective cover. For this purpose, an algorithm has been developed for digital thermograms analising and temperature information deriving at pixel level. The results obtained from the application of the method can be used to evaluate the relay residual life as well as to make early diagnostics of defects due to the contact wearing out.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117226578","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526141
M. Hirman, F. Steiner, J. Hornak, J. Pihera, Pavel Rous
The article presents a research focused on printed circuit board protective coatings as an option for the assembled PCBs cover and electronic device reliability improvement. The experiment with different coatings is described in this article. For the experiment, rigid substrate (FR-4) is used. The protective coatings from acrylic, urethane, silicone and fluoropolymer materials were used. The differences in substrates and coatings have an effect on the insulation resistance which was measured by SIR test. The samples were exposed to accelerated aging test by increased voltage. The advantages, disadvantages, comparison and results from measurement are discussed in this paper. The results present the comparison of the tested conformal coatings. The importance of cleaning before application of coatings is the next part of results.
{"title":"Influence of Increased Voltage on the Characteristics of Printed Circuit Board Protective Coatings","authors":"M. Hirman, F. Steiner, J. Hornak, J. Pihera, Pavel Rous","doi":"10.1109/DIAGNOSTIKA.2018.8526141","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526141","url":null,"abstract":"The article presents a research focused on printed circuit board protective coatings as an option for the assembled PCBs cover and electronic device reliability improvement. The experiment with different coatings is described in this article. For the experiment, rigid substrate (FR-4) is used. The protective coatings from acrylic, urethane, silicone and fluoropolymer materials were used. The differences in substrates and coatings have an effect on the insulation resistance which was measured by SIR test. The samples were exposed to accelerated aging test by increased voltage. The advantages, disadvantages, comparison and results from measurement are discussed in this paper. The results present the comparison of the tested conformal coatings. The importance of cleaning before application of coatings is the next part of results.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114639957","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526133
Theresa Loss, Oliver Gerler, A. Bergmann
Wireless sensor networks are used to guarantee optimal and safe operation of difficult-to-reach industrial and civil structures. Due to their exposed mounting location, the sensors experience severe environmental influences. This leads to erosion and ageing of components which result in drifting standard values. Therefore, online tracking of standard values is paramount to guarantee optimal performance. An algorithm has been developed by fusing measurement data across several sensors during their steady-state. The system is able to track drifting standard values by using long-term memory. Simulations show that the algorithm successfully differentiates between measured data and drift of standard values. Simulations have been verified by applying the algorithm to real-world data of several months. Results show that the algorithm is able to track the drift of standard values, thereby maintaining full sensitivity.
{"title":"Tracking Long- Term Drift in Wireless Sensor Networks Using Long - Term Memory and Data Fusion","authors":"Theresa Loss, Oliver Gerler, A. Bergmann","doi":"10.1109/DIAGNOSTIKA.2018.8526133","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526133","url":null,"abstract":"Wireless sensor networks are used to guarantee optimal and safe operation of difficult-to-reach industrial and civil structures. Due to their exposed mounting location, the sensors experience severe environmental influences. This leads to erosion and ageing of components which result in drifting standard values. Therefore, online tracking of standard values is paramount to guarantee optimal performance. An algorithm has been developed by fusing measurement data across several sensors during their steady-state. The system is able to track drifting standard values by using long-term memory. Simulations show that the algorithm successfully differentiates between measured data and drift of standard values. Simulations have been verified by applying the algorithm to real-world data of several months. Results show that the algorithm is able to track the drift of standard values, thereby maintaining full sensitivity.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128908426","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526084
A. Pietrikova, Tomas Girasek, J. Ďurišin, K. Saksl
The paper describes results of investigations concerning the behaviour of low-temperature silver die attach paste that does not require pressure while curing. Paste is an environmentally friendly product created as a substitute to lead solder, applied in power and high power application. This material has been developed for replacing eutectic solders offering the same thermal performance as AuSn solder. Experimental samples were prepared on standard substrates. Except various curing conditions we analyse quality of joints if various surface quality were used. We compared Au, Ag or AgPt thick films applied on ceramic (Al2O3 or LTCC). First measurements show that joint properties (microstructural analyse, mechanical properties, resistivity of joint, changing the resistance after a constant current loading) are the best on Au thick film applied on LTCC ceramic. Some problems on interface Ag thick film and Ag sintered paste surprised us. Paper describes results of reliability tests as well as.
{"title":"Pressureless Silver Sintering in Power Application","authors":"A. Pietrikova, Tomas Girasek, J. Ďurišin, K. Saksl","doi":"10.1109/DIAGNOSTIKA.2018.8526084","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526084","url":null,"abstract":"The paper describes results of investigations concerning the behaviour of low-temperature silver die attach paste that does not require pressure while curing. Paste is an environmentally friendly product created as a substitute to lead solder, applied in power and high power application. This material has been developed for replacing eutectic solders offering the same thermal performance as AuSn solder. Experimental samples were prepared on standard substrates. Except various curing conditions we analyse quality of joints if various surface quality were used. We compared Au, Ag or AgPt thick films applied on ceramic (Al2O3 or LTCC). First measurements show that joint properties (microstructural analyse, mechanical properties, resistivity of joint, changing the resistance after a constant current loading) are the best on Au thick film applied on LTCC ceramic. Some problems on interface Ag thick film and Ag sintered paste surprised us. Paper describes results of reliability tests as well as.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129639020","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526123
P. Mach, Pavlína Žalská
Electrically conductive adhesives are indispensable materials for mounting some types of electronic components. The resistivity of adhesive joints depends on properties of adhesive, on material and surface quality of connected parts and on a curing schedule of the adhesive. The work is focused on examination the joint resistance in dependence on these parameters. Three types of adhesives with isotropic electrical conductivity have been used for experiments. Adhesives have been applied by stencil printing on the pads having copper and gold surface finish. The joints have been formed by adhesive assembly of jumpers of the type 1206. The strips formed by printing of adhesive between two neighboring pads have also been prepared and measured. Influence of additional curing of the joints on their resistance has been tested with negative results. The results have shown that the joints resistance is dominantly influenced by the curing schedule.
{"title":"Influence of surface finish and additional curing on resistance of adhesive conductive joints","authors":"P. Mach, Pavlína Žalská","doi":"10.1109/DIAGNOSTIKA.2018.8526123","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526123","url":null,"abstract":"Electrically conductive adhesives are indispensable materials for mounting some types of electronic components. The resistivity of adhesive joints depends on properties of adhesive, on material and surface quality of connected parts and on a curing schedule of the adhesive. The work is focused on examination the joint resistance in dependence on these parameters. Three types of adhesives with isotropic electrical conductivity have been used for experiments. Adhesives have been applied by stencil printing on the pads having copper and gold surface finish. The joints have been formed by adhesive assembly of jumpers of the type 1206. The strips formed by printing of adhesive between two neighboring pads have also been prepared and measured. Influence of additional curing of the joints on their resistance has been tested with negative results. The results have shown that the joints resistance is dominantly influenced by the curing schedule.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"113 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134432362","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526124
Kúdelčik Jozef, Emil Jahoda, M. Gutten, J. Hornak, P. Trnka
The influence of 1 wt. % nanoparticles (ZnO, TiO2, SiO2) as fillers in an epoxy resin, known as nanocomposites, on the complex permittivity have been measured. The real and imaginary parts of the complex permittivity and dissipation factor within the frequency ranges from 1 mHz to 1 MHz were measured by a capacitance method. Two mechanisms of polarization processes to an explanation for changes of the complex permittivity were used. α- and β-polarizations processes at the measurement of the temperature dependence of the imaginary permittivity and dissipation factor were observed.
{"title":"Dielectric spectroscopy of nanocomposites","authors":"Kúdelčik Jozef, Emil Jahoda, M. Gutten, J. Hornak, P. Trnka","doi":"10.1109/DIAGNOSTIKA.2018.8526124","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526124","url":null,"abstract":"The influence of 1 wt. % nanoparticles (ZnO, TiO2, SiO2) as fillers in an epoxy resin, known as nanocomposites, on the complex permittivity have been measured. The real and imaginary parts of the complex permittivity and dissipation factor within the frequency ranges from 1 mHz to 1 MHz were measured by a capacitance method. Two mechanisms of polarization processes to an explanation for changes of the complex permittivity were used. α- and β-polarizations processes at the measurement of the temperature dependence of the imaginary permittivity and dissipation factor were observed.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125225819","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526138
M. A. Mehmood, Jian Li, Feipeng Wang, Zhengyong Huang, Jawad Ahmad, M. S. Bhutta
Power transformers are the most essential components of electrical power transmission and distribution networks. During the course of their operation, transformers are subjected to huge electrical and thermal stresses due to which insulation oil inside the transformer is highly degraded. The degradation of insulation oil leads to catastrophic transformer failure which further leads to power system network failure. Hence proper inspection and regular examination of transformer insulation oil is required for smooth and reliable operation of power system. In this research work, insulation oil samples from in-service transformers were taken and analyzed and the results were compared with same grade fresh mineral oil. Absorption spectroscopy techniques e.g. Fourier Transform Infrared Spectroscopy (FTIR) and UV-Visible Spectroscopy were adopted to analyze the insulation oil degradation. The outcome of absorption of aged transformer oil is so significant that absorption increased by observable margin over a wide range of wavelengths. Chemical characterization results highlight that huge amounts of impurities are added to the insulation oil that tend to highly degrade the oil and decrease useful service life of transformer. Hence a proper inspection of the most important part of transformer i.e. insulation oil is required on regular basis.
{"title":"Analyzing the health condition and chemical degradation in field aged transformer insulation oil using spectroscopic techniques","authors":"M. A. Mehmood, Jian Li, Feipeng Wang, Zhengyong Huang, Jawad Ahmad, M. S. Bhutta","doi":"10.1109/DIAGNOSTIKA.2018.8526138","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526138","url":null,"abstract":"Power transformers are the most essential components of electrical power transmission and distribution networks. During the course of their operation, transformers are subjected to huge electrical and thermal stresses due to which insulation oil inside the transformer is highly degraded. The degradation of insulation oil leads to catastrophic transformer failure which further leads to power system network failure. Hence proper inspection and regular examination of transformer insulation oil is required for smooth and reliable operation of power system. In this research work, insulation oil samples from in-service transformers were taken and analyzed and the results were compared with same grade fresh mineral oil. Absorption spectroscopy techniques e.g. Fourier Transform Infrared Spectroscopy (FTIR) and UV-Visible Spectroscopy were adopted to analyze the insulation oil degradation. The outcome of absorption of aged transformer oil is so significant that absorption increased by observable margin over a wide range of wavelengths. Chemical characterization results highlight that huge amounts of impurities are added to the insulation oil that tend to highly degrade the oil and decrease useful service life of transformer. Hence a proper inspection of the most important part of transformer i.e. insulation oil is required on regular basis.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114291412","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526143
B. N. Rao
The progressive deterioration of high voltage machine insulation is assessed through nondestructive techniques like measurement of Insulation Resistance, Polarization index, tan δ & Capacitance and Partial discharge activity mainly for trend analysis. Though a single test cannot indicate the condition of the stator winding insulation, a reasonable assessment can be made by analyzing all the test results together. This paper presents the usefulness of these techniques in condition assessment of winding insulation of generators and motors in service. Several motors and generators were tested at some of the industries, hydro, thermal and nuclear power stations. The results are presented and discussed as case studies.
{"title":"Case Studies of Rotating Machine Insulation Condition Assessment","authors":"B. N. Rao","doi":"10.1109/DIAGNOSTIKA.2018.8526143","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526143","url":null,"abstract":"The progressive deterioration of high voltage machine insulation is assessed through nondestructive techniques like measurement of Insulation Resistance, Polarization index, tan δ & Capacitance and Partial discharge activity mainly for trend analysis. Though a single test cannot indicate the condition of the stator winding insulation, a reasonable assessment can be made by analyzing all the test results together. This paper presents the usefulness of these techniques in condition assessment of winding insulation of generators and motors in service. Several motors and generators were tested at some of the industries, hydro, thermal and nuclear power stations. The results are presented and discussed as case studies.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123912159","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 : 2018-09-01DOI: 10.1109/DIAGNOSTIKA.2018.8526090
T. Okoń, K. Wilkosz
The paper deals with reactive power flow in a power network. One of more essential problems in a power network is a problem of excessive reactive power flows. That problem can be solved by installation of additional sources of reactive power in a power network. With such the solution of the mentioned problem there is associated the following question: Which buses should be considered for installation of additional sources of reactive power? That question can be replaced by the following one: At which buses are there bus reactive powers having the largest impact on reactive power flow in the power network? The paper presents original answer to that question. Using investigation of correlational relationships between bus reactive powers and reactive power flows on branches, the proposed method enables to find the seeked bus reactive powers. In the paper, after theoretical background is outlined, the principle of the new method is given. Next, the case study for reactive power flow in the IEEE 14-bus test system is described. The most important features of the presented method are gathered at the end of the paper.
{"title":"Diagnostics of Reactive Power Flow in a Power Network","authors":"T. Okoń, K. Wilkosz","doi":"10.1109/DIAGNOSTIKA.2018.8526090","DOIUrl":"https://doi.org/10.1109/DIAGNOSTIKA.2018.8526090","url":null,"abstract":"The paper deals with reactive power flow in a power network. One of more essential problems in a power network is a problem of excessive reactive power flows. That problem can be solved by installation of additional sources of reactive power in a power network. With such the solution of the mentioned problem there is associated the following question: Which buses should be considered for installation of additional sources of reactive power? That question can be replaced by the following one: At which buses are there bus reactive powers having the largest impact on reactive power flow in the power network? The paper presents original answer to that question. Using investigation of correlational relationships between bus reactive powers and reactive power flows on branches, the proposed method enables to find the seeked bus reactive powers. In the paper, after theoretical background is outlined, the principle of the new method is given. Next, the case study for reactive power flow in the IEEE 14-bus test system is described. The most important features of the presented method are gathered at the end of the paper.","PeriodicalId":211666,"journal":{"name":"2018 International Conference on Diagnostics in Electrical Engineering (Diagnostika)","volume":"363 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2018-09-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115325387","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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