Pub Date : 2021-08-25DOI: 10.16097/J.CNKI.1009-6744.2021.04.010
Li Shu-qing, Li Qi-feng, Wang Hao, Qin Yan-yan
{"title":"String Stability of Mixed Platoon Under Cooperative AdaptiveCruise Control","authors":"Li Shu-qing, Li Qi-feng, Wang Hao, Qin Yan-yan","doi":"10.16097/J.CNKI.1009-6744.2021.04.010","DOIUrl":"https://doi.org/10.16097/J.CNKI.1009-6744.2021.04.010","url":null,"abstract":"","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"79 1","pages":"82"},"PeriodicalIF":0.0,"publicationDate":"2021-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"80905229","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 : 2021-08-25DOI: 10.16097/J.CNKI.1009-6744.2021.04.016
Wang Fu-jian, LU Yi-xiao, Jin Sheng
{"title":"Travel Time Characteristics Analysis of Arterial Roads withMultiple Signalized Intersections","authors":"Wang Fu-jian, LU Yi-xiao, Jin Sheng","doi":"10.16097/J.CNKI.1009-6744.2021.04.016","DOIUrl":"https://doi.org/10.16097/J.CNKI.1009-6744.2021.04.016","url":null,"abstract":"","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"53 1","pages":"132"},"PeriodicalIF":0.0,"publicationDate":"2021-08-25","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"78186461","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 : 2021-07-01DOI: 10.17816/TRANSSYST202172130-141
V. Yushchenko, V. Khrapov
Background: The formation of mechanisms for sustainable development of the transport system of Russia should be aimed at improving its competitiveness. Aim: Development of technical and economic foundations for improving the efficiency of the transport system of Russia, on the example of railway transport. Methods: Theoretical methods of scientific research were used to achieve the goal: analysis, synthesis and modeling. Results: The original concept of "Coincidental freight transportation" with the necessity of technical modernization of freight cars is offered. The concepts of a coincidental route and a coincidental wagon are analyzed, and application of the mathematical apparatus for economic evaluation of the results is recommended.
{"title":"The concept of \"coincidental cargo transportation\" as a mechanism to improve the efficiency \u0000of railway transport","authors":"V. Yushchenko, V. Khrapov","doi":"10.17816/TRANSSYST202172130-141","DOIUrl":"https://doi.org/10.17816/TRANSSYST202172130-141","url":null,"abstract":"Background: The formation of mechanisms for sustainable development of the transport system of Russia should be aimed at improving its competitiveness. \u0000Aim: Development of technical and economic foundations for improving the efficiency of the transport system of Russia, on the example of railway transport. \u0000Methods: Theoretical methods of scientific research were used to achieve the goal: analysis, synthesis and modeling. \u0000Results: The original concept of \"Coincidental freight transportation\" with the necessity of technical modernization of freight cars is offered. The concepts of a coincidental route and a coincidental wagon are analyzed, and application of the mathematical apparatus for economic evaluation of the results is recommended.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"32 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"75831199","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 : 2021-07-01DOI: 10.17816/TRANSSYST20217255-75
Veronika A. Manova, A. Lebedeva, Olesya N. Noviniuk, Vladimir V. Syropyatov
The article analyzes the existing methods for assessing the readiness of territories for the formation of a logistics complex, examines the factors affecting the formation of the infrastructure of an innovative port logistics complex. An author's method for assessing the readiness of territories for the formation of the infrastructure of an innovative port logistics complex.
{"title":"Methodology for assessing the readiness of territories for the formation of the infrastructure of the innovative port logistics complex","authors":"Veronika A. Manova, A. Lebedeva, Olesya N. Noviniuk, Vladimir V. Syropyatov","doi":"10.17816/TRANSSYST20217255-75","DOIUrl":"https://doi.org/10.17816/TRANSSYST20217255-75","url":null,"abstract":"The article analyzes the existing methods for assessing the readiness of territories for the formation of a logistics complex, examines the factors affecting the formation of the infrastructure of an innovative port logistics complex. An author's method for assessing the readiness of territories for the formation of the infrastructure of an innovative port logistics complex.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"210 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77756010","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 : 2021-07-01DOI: 10.17816/TRANSSYST20217297-105
E. Miroshnichenko
Aim: Establishment of preconditions for the introduction of a switched reluctance motor into the system of traction drive of an electric rolling stock by improving the performance of the bearing unit. Methods: Calculations were carried out using the finite element method. Results: It was found that the calculated values of force of a one-way magnetic attraction applied to the bearing unit are tens of times higher than the permissible values. The result is accelerated wear and failure of the bearings. An algorithm is proposed which takes into account the influence of one-way magnetic attraction forces in an uneven air gap. Conclusion: The algorithm makes it possible to change the production cycle and improve the consumer quality of the switched reluctance traction motor.
{"title":"Switched reluctance traction motor with improved indicators of the reliability of bearing units for an electric rolling stoсk","authors":"E. Miroshnichenko","doi":"10.17816/TRANSSYST20217297-105","DOIUrl":"https://doi.org/10.17816/TRANSSYST20217297-105","url":null,"abstract":"Aim: Establishment of preconditions for the introduction of a switched reluctance motor into the system of traction drive of an electric rolling stock by improving the performance of the bearing unit. \u0000Methods: Calculations were carried out using the finite element method. \u0000Results: It was found that the calculated values of force of a one-way magnetic attraction applied to the bearing unit are tens of times higher than the permissible values. The result is accelerated wear and failure of the bearings. An algorithm is proposed which takes into account the influence of one-way magnetic attraction forces in an uneven air gap. \u0000Conclusion: The algorithm makes it possible to change the production cycle and improve the consumer quality of the switched reluctance traction motor.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"57 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82626077","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 : 2021-07-01DOI: 10.17816/TRANSSYST20217242-54
A. A. Trifonova, S. Alekseev, Alexey M. Yegoshin
At present, there are high requirements for materials and construction elements in civil engineering in common. These intentions are fully applicable to such bridge construction elements as expansion joints. The new developed models are needed, in which all the defects and limitations of the previous models are solved and the maximum of operational life is reached. The main types of bridge expansion joints: closed joints, filled-type joints, covered joints. In this article the construction features, advantages and disadvantages of the listed expansion joints are considered. On the basis of the gotten results it is seen that new and developed models of different types expansion joints have better rates in all of considered criteria. It means that these joints have bigger structural reliability and provide longer operational life of the construction. The most effective models of bridge expansion joints are: closed-type joints with metal support plate, filled-type joints with convex V-shaped compensator and covering slab, covered joints with finger slabs and flap hinged rods and springs.
{"title":"Resent constructions of road bridges’ expansion joints","authors":"A. A. Trifonova, S. Alekseev, Alexey M. Yegoshin","doi":"10.17816/TRANSSYST20217242-54","DOIUrl":"https://doi.org/10.17816/TRANSSYST20217242-54","url":null,"abstract":"At present, there are high requirements for materials and construction elements in civil engineering in common. These intentions are fully applicable to such bridge construction elements as expansion joints. The new developed models are needed, in which all the defects and limitations of the previous models are solved and the maximum of operational life is reached. \u0000The main types of bridge expansion joints: closed joints, filled-type joints, covered joints. In this article the construction features, advantages and disadvantages of the listed expansion joints are considered. \u0000On the basis of the gotten results it is seen that new and developed models of different types expansion joints have better rates in all of considered criteria. It means that these joints have bigger structural reliability and provide longer operational life of the construction. The most effective models of bridge expansion joints are: closed-type joints with metal support plate, filled-type joints with convex V-shaped compensator and covering slab, covered joints with finger slabs and flap hinged rods and springs.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"46 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83675681","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 : 2021-07-01DOI: 10.17816/TRANSSYST20217287-96
V. A. Solomin, A. Solomin, A. A. Chekhova
Background: Development and research of linear traction drives for Maglev transport is an urgent task. Linear induction motors can be used as traction machines for advanced rolling stock. Aim: Study of the starting characteristics of an adjustable traction linear induction motor with variable resistance by a short-circuited winding of the secondary element. Methods: Theoretically, relations were obtained for calculating the traction starting forces of an adjustable linear induction motor with various designs of a short-circuited winding of the secondary element. Results: Based on the obtained ratios, the calculations of the starting traction forces of linear induction motors intended for use in promising modes of transport were performed. Conclusion: The results of calculating the starting traction forces of adjustable linear induction motors make it possible to reasonably select the modes of starting the motor depending on the design of the secondary winding.
{"title":"Starting forces of the traction linear induction motor with adjustable resistance of the short-circuited winding of the secondary element","authors":"V. A. Solomin, A. Solomin, A. A. Chekhova","doi":"10.17816/TRANSSYST20217287-96","DOIUrl":"https://doi.org/10.17816/TRANSSYST20217287-96","url":null,"abstract":"Background: Development and research of linear traction drives for Maglev transport is an urgent task. Linear induction motors can be used as traction machines for advanced rolling stock. \u0000Aim: Study of the starting characteristics of an adjustable traction linear induction motor with variable resistance by a short-circuited winding of the secondary element. \u0000Methods: Theoretically, relations were obtained for calculating the traction starting forces of an adjustable linear induction motor with various designs of a short-circuited winding of the secondary element. \u0000Results: Based on the obtained ratios, the calculations of the starting traction forces of linear induction motors intended for use in promising modes of transport were performed. \u0000Conclusion: The results of calculating the starting traction forces of adjustable linear induction motors make it possible to reasonably select the modes of starting the motor depending on the design of the secondary winding.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"51 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76264727","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 : 2021-07-01DOI: 10.17816/TRANSSYST202172119-129
Yuri F. Antonov
Background: The methods of calculation and elements of the technology for creating heteropolar magnetic systems of levitation, lateral stabilization and a rotor-runner of a traction linear synchronous motor for the development of the transport technology "Russian Maglev" in order to achieve an increased levitation gap of 0.2 m, reduce the threshold speed of the exit vehicle in levitation mode up to 10 km/h. Aim: to develop methods for calculating and designing heteropolar poles from elementary permanent magnets, coils of the same type based on composite low-temperature superconductors and high-temperature tape superconductors of the second generation and a step-by-step technology for their production. Tasks: Creation of an on-board magnetic system of levitation and lateral stabilization, allowing to provide a levitation gap of 0.2 m, a threshold value of vehicle speed of 10 km/h when transition to levitation mode, to reduce stray magnetic fields to the level of the natural field of terrestrial magnetism of 50 T; Creation of a rotor-runner of a linear synchronous motor with an ironless stator with a power of 10 MW. Methods: outlines the main calculation methodologies: "analysis" and "synthesis". The "analysis" methodology is adopted in solving the "direct" calculation problem, when the configuration of the magnetic system is set and the magnetic field in the working area is calculated, and, if necessary, the stray magnetic fields. This methodology can be effectively applied if there is experience in creating magnetic systems. Otherwise, the "synthesis" methodology is applied, which is used in solving the "inverse" calculation problem, in which the picture of the distribution of the magnetic field in the working zone is set and the configuration of the magnetic system is found (synthesized). Results of the study performed: The parameters and characteristics of high-energy permanent magnets made of rare-earth metals, low-temperature and high-temperature superconducting winding materials have been analyzed, the choice of permanent magnets and superconducting winding material has been made; Calculations of the magnetic system of permanent magnets in the "Halbach assembly" and in the traditional assembly in a toothed ferromagnetic core have been carried out; Calculations of a track coil with a rectangular cross-section of the winding are performed; Methods for calculating and optimizing superconducting magnetic systems from a set of similar track modules have been developed; Conclusions: The results of the performed fundamental research will allow starting the calculation, design and construction of conveyor-main passenger and freight lines of maglev transport, as well as urban public transport.
{"title":"Calculation, design and manufacture of heteropolar magnetic levitation and linear drive systems of maglev transport","authors":"Yuri F. Antonov","doi":"10.17816/TRANSSYST202172119-129","DOIUrl":"https://doi.org/10.17816/TRANSSYST202172119-129","url":null,"abstract":"Background: The methods of calculation and elements of the technology for creating heteropolar magnetic systems of levitation, lateral stabilization and a rotor-runner of a traction linear synchronous motor for the development of the transport technology \"Russian Maglev\" in order to achieve an increased levitation gap of 0.2 m, reduce the threshold speed of the exit vehicle in levitation mode up to 10 km/h. \u0000Aim: to develop methods for calculating and designing heteropolar poles from elementary permanent magnets, coils of the same type based on composite low-temperature superconductors and high-temperature tape superconductors of the second generation and a step-by-step technology for their production. \u0000Tasks: \u0000 \u0000Creation of an on-board magnetic system of levitation and lateral stabilization, allowing to provide a levitation gap of 0.2 m, a threshold value of vehicle speed of 10 km/h when transition to levitation mode, to reduce stray magnetic fields to the level of the natural field of terrestrial magnetism of 50 T; \u0000Creation of a rotor-runner of a linear synchronous motor with an ironless stator with a power of 10 MW. \u0000 \u0000Methods: outlines the main calculation methodologies: \"analysis\" and \"synthesis\". The \"analysis\" methodology is adopted in solving the \"direct\" calculation problem, when the configuration of the magnetic system is set and the magnetic field in the working area is calculated, and, if necessary, the stray magnetic fields. This methodology can be effectively applied if there is experience in creating magnetic systems. Otherwise, the \"synthesis\" methodology is applied, which is used in solving the \"inverse\" calculation problem, in which the picture of the distribution of the magnetic field in the working zone is set and the configuration of the magnetic system is found (synthesized). \u0000Results of the study performed: \u0000 \u0000The parameters and characteristics of high-energy permanent magnets made of rare-earth metals, low-temperature and high-temperature superconducting winding materials have been analyzed, the choice of permanent magnets and superconducting winding material has been made; \u0000Calculations of the magnetic system of permanent magnets in the \"Halbach assembly\" and in the traditional assembly in a toothed ferromagnetic core have been carried out; \u0000Calculations of a track coil with a rectangular cross-section of the winding are performed; \u0000Methods for calculating and optimizing superconducting magnetic systems from a set of similar track modules have been developed; \u0000 \u0000Conclusions: The results of the performed fundamental research will allow starting the calculation, design and construction of conveyor-main passenger and freight lines of maglev transport, as well as urban public transport.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"56 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77871063","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 : 2021-07-01DOI: 10.17816/TRANSSYST202172106-118
I. Kazymov, B. Kompaneets, O. N. Drobyazko
Background: The creation and distribution of technical means and complexes aimed at building effective control systems for electrical networks using information that can be collected by modern metering devices, as well as organizing work in an automated mode, is an urgent task at the present stage of development of the electric power industry in Russia and in the world. Aim: The research presented in this article is aimed at creating an effective system for monitoring the parameters of electrical energy in distribution networks of low and medium voltage levels. Methods: The study was carried out using the theoretical foundations and basic laws of electrical engineering, as well as methods of computer modeling and CAD. Results: A description of the developed system is given, the applicability of its use is graphically shown and substantiated in writing, the possibilities and prospects of application are indicated, and recommendations for practical application are given. Conclusion: The results obtained can be used by power grid companies to analyze the state and efficiency of power grids, and may also be of interest to researchers working on the creation of digital twins of power grids.
{"title":"Development of a system for control of electric energy parameters in the distribution network","authors":"I. Kazymov, B. Kompaneets, O. N. Drobyazko","doi":"10.17816/TRANSSYST202172106-118","DOIUrl":"https://doi.org/10.17816/TRANSSYST202172106-118","url":null,"abstract":"Background: The creation and distribution of technical means and complexes aimed at building effective control systems for electrical networks using information that can be collected by modern metering devices, as well as organizing work in an automated mode, is an urgent task at the present stage of development of the electric power industry in Russia and in the world. \u0000Aim: The research presented in this article is aimed at creating an effective system for monitoring the parameters of electrical energy in distribution networks of low and medium voltage levels. \u0000Methods: The study was carried out using the theoretical foundations and basic laws of electrical engineering, as well as methods of computer modeling and CAD. \u0000Results: A description of the developed system is given, the applicability of its use is graphically shown and substantiated in writing, the possibilities and prospects of application are indicated, and recommendations for practical application are given. \u0000Conclusion: The results obtained can be used by power grid companies to analyze the state and efficiency of power grids, and may also be of interest to researchers working on the creation of digital twins of power grids.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"40 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81262381","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 : 2021-07-01DOI: 10.17816/TRANSSYST2021725-15
A. Agunov, I. Terekhin, I. Baranov
At present, on the territory of the Russian Federation, there is no massive use of electrically conductive reinforced concrete structures in the electric power industry due to insufficient operating experience and a low rate of research on electrically conductive concretes. The article compares the main characteristics of existing electrically conductive concrete. The paper shows the disadvantages of traditional concrete and existing electrically conductive concrete. The electrically conductive concrete was selected, the most suitable for further research, testing and direct modernization of the composition based on the results obtained. The main disadvantages of existing electrically conductive concretes are the high cost and specificity of electrically conductive components and other additives, as a consequence of the amount of capital investment in mass and large-scale production, as well as the lack of operating experience as overhead supports.
{"title":"Analysis of the application of electric conducting concrete in the power industry","authors":"A. Agunov, I. Terekhin, I. Baranov","doi":"10.17816/TRANSSYST2021725-15","DOIUrl":"https://doi.org/10.17816/TRANSSYST2021725-15","url":null,"abstract":"At present, on the territory of the Russian Federation, there is no massive use of electrically conductive reinforced concrete structures in the electric power industry due to insufficient operating experience and a low rate of research on electrically conductive concretes. \u0000The article compares the main characteristics of existing electrically conductive concrete. The paper shows the disadvantages of traditional concrete and existing electrically conductive concrete. The electrically conductive concrete was selected, the most suitable for further research, testing and direct modernization of the composition based on the results obtained. \u0000The main disadvantages of existing electrically conductive concretes are the high cost and specificity of electrically conductive components and other additives, as a consequence of the amount of capital investment in mass and large-scale production, as well as the lack of operating experience as overhead supports.","PeriodicalId":100849,"journal":{"name":"Journal of Transportation Systems Engineering and Information Technology","volume":"17 1","pages":""},"PeriodicalIF":0.0,"publicationDate":"2021-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81089331","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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