Pub Date : 2014-12-04DOI: 10.1109/ICATE.2014.6972688
L. Dinca, J. Corcau
This paper presents an overview of several converter topologies used in practice and also their digital command. A special attention is given to digital control based on microcontroller. We choose this option because we can implement different strategies like fuzzy, neuro-fuzzy and sliding mode. Also, this kind of digital control can be integrated along with the converter into a computer controlled system where the hierarchic command is done by a process computer. The digital control studied in this paper will be integrated into a dc to dc Boost Converter.
{"title":"Digital control for DC to DC converter","authors":"L. Dinca, J. Corcau","doi":"10.1109/ICATE.2014.6972688","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972688","url":null,"abstract":"This paper presents an overview of several converter topologies used in practice and also their digital command. A special attention is given to digital control based on microcontroller. We choose this option because we can implement different strategies like fuzzy, neuro-fuzzy and sliding mode. Also, this kind of digital control can be integrated along with the converter into a computer controlled system where the hierarchic command is done by a process computer. The digital control studied in this paper will be integrated into a dc to dc Boost Converter.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"375 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126432277","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 : 2014-12-04DOI: 10.1109/ICATE.2014.6972631
R. Dinu, N. Popescu, Felicia-Elena Stan Ivan, E. Dinu
Given the continued escalation of fuel prices, especially the price of natural gas is particularly important to obtain in residential, social, cultural and administrative conditions for thermal comfort with minimum energy costs. In this paper, the authors present issues regarding the energy and economic efficiency of the centralized heat supply of the thermal consumers. This analysis is the starting point regarding the decision to modernize and increase the energy efficiency of transport systems and heat supply in urban areas of our country.
{"title":"Study of thermal energy supply to urban localities","authors":"R. Dinu, N. Popescu, Felicia-Elena Stan Ivan, E. Dinu","doi":"10.1109/ICATE.2014.6972631","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972631","url":null,"abstract":"Given the continued escalation of fuel prices, especially the price of natural gas is particularly important to obtain in residential, social, cultural and administrative conditions for thermal comfort with minimum energy costs. In this paper, the authors present issues regarding the energy and economic efficiency of the centralized heat supply of the thermal consumers. This analysis is the starting point regarding the decision to modernize and increase the energy efficiency of transport systems and heat supply in urban areas of our country.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125969057","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 : 2014-12-04DOI: 10.1109/ICATE.2014.6972607
L. Alboteanu, Florin Ravigan, A. Novac
It is known as photovoltaic (PV) panels have a low energy efficiency. A solution of increasing energy efficiency consists in use of sunlight concentrating elements equipped with automatic tracking systems. This paper presents aspects of designing an automaton for PV panels tracking system fitted with low sunlight concentrating elements.
{"title":"Design of a sun tracking automaton for photovoltaic panels with low concentration of solar radiation","authors":"L. Alboteanu, Florin Ravigan, A. Novac","doi":"10.1109/ICATE.2014.6972607","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972607","url":null,"abstract":"It is known as photovoltaic (PV) panels have a low energy efficiency. A solution of increasing energy efficiency consists in use of sunlight concentrating elements equipped with automatic tracking systems. This paper presents aspects of designing an automaton for PV panels tracking system fitted with low sunlight concentrating elements.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124667758","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 : 2014-12-04DOI: 10.1109/ICATE.2014.6972601
C. Rusu, M. Radulescu, Szöke Enikö, Radian K. Melinda, Zsolt L. Jakab
Rapid prototyping is the typical method used by engineers to develop and test control strategies. The paper presents an Embedded Motor Drive test bench for developing and study energy efficient of motor drives. The prototyping platform system uses Matlab/Simulink and Target Support Package for TI C2000 toolbox. A real-time target controller eZdsp F2812 provided with a power stage inverter represents the hardware components since these can run multiple complex control algorithms. A graphical programming interface with hardware-in-loop design process for testing the algorithms is used. The hardware platform integrates the most recent digital signal processing technology and state-of-the-art design methods. Application performances of electrical drive require energy efficiency, flexibility, outstanding reliability and robust control. Servo drives with Permanent Magnet Synchronous Motors (PMSM) have wide industrial applications where the speed and torque responses at the high-performance operations are required. Most of the controllers are implemented by field-orientation control mode (FOC) since the method laid the motors at maximum theoretical performances. The PMSM control algorithms are tested in a rapid prototyping approach using Matlab/Simulink and the Real Time Workshop (RTW) toolbox. This low cost prototyping control system can be used as teaching tools in the most graduate-level courses in classical and/or modern control theory.
快速原型设计是工程师开发和测试控制策略的典型方法。本文提出了一种嵌入式电机驱动试验台，用于开发和研究电机驱动的节能性能。原型平台系统采用Matlab/Simulink和Target Support Package for TI C2000工具箱。配备功率级逆变器的实时目标控制器eZdsp F2812代表硬件组件，因为这些组件可以运行多种复杂的控制算法。使用图形化编程界面和硬件在环设计过程来测试算法。硬件平台集成了最新的数字信号处理技术和最先进的设计方法。电力驱动的应用性能要求节能、灵活、出色的可靠性和鲁棒性控制。永磁同步电机(PMSM)伺服驱动器具有广泛的工业应用，其中需要在高性能操作下的速度和扭矩响应。由于该方法能使电机达到最大的理论性能，因此大多数控制器都采用场定向控制模式(FOC)实现。使用Matlab/Simulink和Real Time Workshop (RTW)工具箱在快速原型方法中测试了PMSM控制算法。这种低成本的原型控制系统可以用作经典和/或现代控制理论的大多数研究生课程的教学工具。
{"title":"Embedded motor drive prototype platform for testing control algorithms","authors":"C. Rusu, M. Radulescu, Szöke Enikö, Radian K. Melinda, Zsolt L. Jakab","doi":"10.1109/ICATE.2014.6972601","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972601","url":null,"abstract":"Rapid prototyping is the typical method used by engineers to develop and test control strategies. The paper presents an Embedded Motor Drive test bench for developing and study energy efficient of motor drives. The prototyping platform system uses Matlab/Simulink and Target Support Package for TI C2000 toolbox. A real-time target controller eZdsp F2812 provided with a power stage inverter represents the hardware components since these can run multiple complex control algorithms. A graphical programming interface with hardware-in-loop design process for testing the algorithms is used. The hardware platform integrates the most recent digital signal processing technology and state-of-the-art design methods. Application performances of electrical drive require energy efficiency, flexibility, outstanding reliability and robust control. Servo drives with Permanent Magnet Synchronous Motors (PMSM) have wide industrial applications where the speed and torque responses at the high-performance operations are required. Most of the controllers are implemented by field-orientation control mode (FOC) since the method laid the motors at maximum theoretical performances. The PMSM control algorithms are tested in a rapid prototyping approach using Matlab/Simulink and the Real Time Workshop (RTW) toolbox. This low cost prototyping control system can be used as teaching tools in the most graduate-level courses in classical and/or modern control theory.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127873836","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 : 2014-12-04DOI: 10.1109/ICATE.2014.6972652
Mihaela-Codruta Ancuti, M. Svoboda, S. Musuroi, A. Hedeş, N. Olarescu
The main drawback related to the PFC converters is the increasing of the electromagnetic interference (EMI). Thus, the high frequency noise must be filter out in order to ensure compliance with EMI European standards (EN 1000-3-2 or EN 1000-3-4). The paper investigates two topologies: the conventional boost PFC converter and the bridgeless boost PFC converter. A proper filter is designed and its details are presented. Their evaluation is done in regards to electromagnetic compatibility (EMC) requirements, which is very important in the residential ambient (for the power range up to 4 kW). The FFT analysis, done in Matlab/Simulink is presented for comparison and it verifies the compliance of the selected topologies with the norms.
{"title":"Boost PFC converter versus bridgeless boost PFC converter EMI analysis","authors":"Mihaela-Codruta Ancuti, M. Svoboda, S. Musuroi, A. Hedeş, N. Olarescu","doi":"10.1109/ICATE.2014.6972652","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972652","url":null,"abstract":"The main drawback related to the PFC converters is the increasing of the electromagnetic interference (EMI). Thus, the high frequency noise must be filter out in order to ensure compliance with EMI European standards (EN 1000-3-2 or EN 1000-3-4). The paper investigates two topologies: the conventional boost PFC converter and the bridgeless boost PFC converter. A proper filter is designed and its details are presented. Their evaluation is done in regards to electromagnetic compatibility (EMC) requirements, which is very important in the residential ambient (for the power range up to 4 kW). The FFT analysis, done in Matlab/Simulink is presented for comparison and it verifies the compliance of the selected topologies with the norms.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126147620","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.1109/ICATE.2014.6972661
A. Marinescu, I. Dumbravă
The measurement and monitoring of some important parameters characteristic for the equipment health evolution, from the moment of leaving the manufacturing company and throughout the active life, is contained in the standards in the field and followed carefully by the organizations that use the equipment. The paper deals with issues related to the accurate measurement of Partial Discharges (PD) level in the electrical insulation and, in particular, to the sensors used for this purpose. Lately, inductive current sensors are more and more used instead of the classical measuring impedances of RLC type provided in the standards in force, but the adequacy of their characteristics to the phenomena under study is not experimentally verified. The design of some dedicated wide band pulse current transformers (PCTs) with high sensitivity which, unlike those usually used, have a high permeability nano-crystalline magnetic core is analyzed. Their behavior is studied in the time and frequency domains for determining the sensitivity and the frequency band adapted to be used for Phase Resolving Partial Discharge Analysis (PRPDA). The response of PCTs achieved by authors is compared with the response of other commercial PCTs and with the response of some classical measuring impedances, by using current pulses produced by professional PD calibrators. It is described their application for PD measurement at power transformers.
{"title":"Nano-crystalline magnetic core pulse CT development and assessment for partial discharge measurements","authors":"A. Marinescu, I. Dumbravă","doi":"10.1109/ICATE.2014.6972661","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972661","url":null,"abstract":"The measurement and monitoring of some important parameters characteristic for the equipment health evolution, from the moment of leaving the manufacturing company and throughout the active life, is contained in the standards in the field and followed carefully by the organizations that use the equipment. The paper deals with issues related to the accurate measurement of Partial Discharges (PD) level in the electrical insulation and, in particular, to the sensors used for this purpose. Lately, inductive current sensors are more and more used instead of the classical measuring impedances of RLC type provided in the standards in force, but the adequacy of their characteristics to the phenomena under study is not experimentally verified. The design of some dedicated wide band pulse current transformers (PCTs) with high sensitivity which, unlike those usually used, have a high permeability nano-crystalline magnetic core is analyzed. Their behavior is studied in the time and frequency domains for determining the sensitivity and the frequency band adapted to be used for Phase Resolving Partial Discharge Analysis (PRPDA). The response of PCTs achieved by authors is compared with the response of other commercial PCTs and with the response of some classical measuring impedances, by using current pulses produced by professional PD calibrators. It is described their application for PD measurement at power transformers.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126636683","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.1109/ICATE.2014.6972636
I. Vlad, A. Câmpeanu, S. Enache, M. Enache
The objectives followed in the frame of this paper are to approach comparatively, from the view point of the operation performances and exploitation costs obtained for two types of motors (asynchronous motor and permanent-magnet synchronous motor), by means of some specialized computation soft-wares. Because of the drawbacks of asynchronous motors (high shock of starting current, relatively low power factor, rigid mechanical characteristic), these motors have been replaced, in case of low power, by permanent-magnet synchronous motors, which have good efficiency and good power factor. By this change, the exploitation cost is reduced, the active power losses decrease with 10.6% and the reactive power consumption is reduced with. All these benefits appear in the detriment of some low increases in the fabrication cost, machine weight and gauge dimensions.
{"title":"Analysis of exploitation cost at low power alternating current motors and optimization possibilities","authors":"I. Vlad, A. Câmpeanu, S. Enache, M. Enache","doi":"10.1109/ICATE.2014.6972636","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972636","url":null,"abstract":"The objectives followed in the frame of this paper are to approach comparatively, from the view point of the operation performances and exploitation costs obtained for two types of motors (asynchronous motor and permanent-magnet synchronous motor), by means of some specialized computation soft-wares. Because of the drawbacks of asynchronous motors (high shock of starting current, relatively low power factor, rigid mechanical characteristic), these motors have been replaced, in case of low power, by permanent-magnet synchronous motors, which have good efficiency and good power factor. By this change, the exploitation cost is reduced, the active power losses decrease with 10.6% and the reactive power consumption is reduced with. All these benefits appear in the detriment of some low increases in the fabrication cost, machine weight and gauge dimensions.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115104537","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.1109/ICATE.2014.6972671
P. Mircea, Cosmin Buzatu, I. Mircea
Compressed air occupies an important place among energy consumers in specialized industry. In this paper, the authors present the results of the monitoring and analysis for the parameters of a compressed air system to an industrial unit, obtained using equipment specialized in monitoring and measurements for compressed air.
{"title":"Analysis and monitoring of the compressed air facilities","authors":"P. Mircea, Cosmin Buzatu, I. Mircea","doi":"10.1109/ICATE.2014.6972671","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972671","url":null,"abstract":"Compressed air occupies an important place among energy consumers in specialized industry. In this paper, the authors present the results of the monitoring and analysis for the parameters of a compressed air system to an industrial unit, obtained using equipment specialized in monitoring and measurements for compressed air.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129912775","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.1109/ICATE.2014.6972619
S. Abagiu, I. Lepadat, E. Helerea
Associated phenomena usually to interruption of neutral conductor and to change of the dispersion earth resistance touch a sensitive aspect of low-voltage power networks. Therefore, a tool is needed to evaluate the risks associated with this behaviour. This paper proposes a mathematical model to describe realistic influence of dispersion earth resistance of earth electrode and unbalanced power supply system of the consumer, the phase currents and voltages on the consumer. These phenomena are directly related to the power quality and efficiency of protective system, especially in case of three-phase unbalanced consumers. In this paper it is shown that the neutral displacement voltage, neutral current and phase currents and voltages depend on the severity of the unbalance of three-phase consumer and of the value of three-phase dispersion earth resistance. Simulations are made for consumer operation in case of unbalanced regime with the dispersion earth resistance of earth electrode from downstream of fault location equal to 4 Ω, 2 Ω and 1 Ω. The results are useful for the design and operation of the protective system.
{"title":"Influence of dispersion earth resistance variation on the consumers operation","authors":"S. Abagiu, I. Lepadat, E. Helerea","doi":"10.1109/ICATE.2014.6972619","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972619","url":null,"abstract":"Associated phenomena usually to interruption of neutral conductor and to change of the dispersion earth resistance touch a sensitive aspect of low-voltage power networks. Therefore, a tool is needed to evaluate the risks associated with this behaviour. This paper proposes a mathematical model to describe realistic influence of dispersion earth resistance of earth electrode and unbalanced power supply system of the consumer, the phase currents and voltages on the consumer. These phenomena are directly related to the power quality and efficiency of protective system, especially in case of three-phase unbalanced consumers. In this paper it is shown that the neutral displacement voltage, neutral current and phase currents and voltages depend on the severity of the unbalance of three-phase consumer and of the value of three-phase dispersion earth resistance. Simulations are made for consumer operation in case of unbalanced regime with the dispersion earth resistance of earth electrode from downstream of fault location equal to 4 Ω, 2 Ω and 1 Ω. The results are useful for the design and operation of the protective system.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126891046","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Pub Date : 2014-10-01DOI: 10.1109/ICATE.2014.6972669
R. Munteanu, H. Balan, A. Pop, M. Buzdugan
Monitoring of electrical equipment is a direction of current development in the maintenance domain. The method aims to establish the operation state of the monitored equipment. Fault diagnosis existing on power circuit breakers is very important aspect in emergency situations, when it must be interrupted by high current circuit breakers. This paper presents a model of vibration monitoring using Wavelet-Morlet transform. Here are reviewed theoretical problems of using Wavelet-Morlet transform, signal processing techniques and experimental results that highlight the difference between faulty equipment and one in a proper working condition.
{"title":"Wavelet analysis in monitoring and diagnosis of power circuit breakers","authors":"R. Munteanu, H. Balan, A. Pop, M. Buzdugan","doi":"10.1109/ICATE.2014.6972669","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972669","url":null,"abstract":"Monitoring of electrical equipment is a direction of current development in the maintenance domain. The method aims to establish the operation state of the monitored equipment. Fault diagnosis existing on power circuit breakers is very important aspect in emergency situations, when it must be interrupted by high current circuit breakers. This paper presents a model of vibration monitoring using Wavelet-Morlet transform. Here are reviewed theoretical problems of using Wavelet-Morlet transform, signal processing techniques and experimental results that highlight the difference between faulty equipment and one in a proper working condition.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129865849","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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