Pub Date : 2014-10-01DOI: 10.1109/ICATE.2014.6972647
H. Balan, M. Buzdugan, A. Pop, R. Munteanu
Several fixed frequency applications of multilevel converters require a very low level of distortion factor of the output voltage. Bringing the output voltage to a form as close as possible to a sine wave is usually done through linearization methods of the Newton-Raphson algebraic equations. The method proposed in section III uses for the waveforms optimization a genetic algorithm, having a positive impact on the total harmonic distortion reduction. Experimental validation of the method is performed using a programmable source which drives an induction motor.
{"title":"Performances optimization and characteristics of the voltage generated by multilevel inverters","authors":"H. Balan, M. Buzdugan, A. Pop, R. Munteanu","doi":"10.1109/ICATE.2014.6972647","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972647","url":null,"abstract":"Several fixed frequency applications of multilevel converters require a very low level of distortion factor of the output voltage. Bringing the output voltage to a form as close as possible to a sine wave is usually done through linearization methods of the Newton-Raphson algebraic equations. The method proposed in section III uses for the waveforms optimization a genetic algorithm, having a positive impact on the total harmonic distortion reduction. Experimental validation of the method is performed using a programmable source which drives an induction motor.","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":"130227583","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.2014.6972632
Ion-Daniel Ilina
The paper presents a study of heating for induction machine, using the theory of the two thermal bodies. This theory gives good results for low power machines. The differential equations of heat are discussed and a simple thermal equivalent circuit is proposed for the machine. From the experimental tests, the equation of heating in the theory of the two thermal bodies is determined for the induction machine and the results are analyzed.
{"title":"Heating study of induction machine using the theory of the two thermal bodies","authors":"Ion-Daniel Ilina","doi":"10.1109/ICATE.2014.6972632","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972632","url":null,"abstract":"The paper presents a study of heating for induction machine, using the theory of the two thermal bodies. This theory gives good results for low power machines. The differential equations of heat are discussed and a simple thermal equivalent circuit is proposed for the machine. From the experimental tests, the equation of heating in the theory of the two thermal bodies is determined for the induction machine and the results are analyzed.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"25 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":"133203538","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.2014.6972672
Livia-Andreea Dina, E. Stoenescu, Ionuţ-Daniel Smărăndescu
The paper deals with the designing of a flue gases filtering equipment (electrofilter) for a 330 MW power group from a thermal power plant that uses coal as fuel. The advanced designing was performed using the software MathCAD. In the paper are presented the economic issues on the cost of the equipment but also the operation of the electrofilter's electrical equipment.
{"title":"On reducing the atmospheric pollution by using an electrofilter afferent to a 330 MW power group","authors":"Livia-Andreea Dina, E. Stoenescu, Ionuţ-Daniel Smărăndescu","doi":"10.1109/ICATE.2014.6972672","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972672","url":null,"abstract":"The paper deals with the designing of a flue gases filtering equipment (electrofilter) for a 330 MW power group from a thermal power plant that uses coal as fuel. The advanced designing was performed using the software MathCAD. In the paper are presented the economic issues on the cost of the equipment but also the operation of the electrofilter's electrical equipment.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"3 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":"122303239","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.2014.6972666
M. Duta, S. Vlase, N. Anoaica, V. Voicu, D. Iovan, A. Benea, C. Salceanu, C. Dobrea
This article presents the result of the research carried out for the modernization of the constructive solutions for classic current limiting fuses defined in IEC 60282-1 /2009 used for the protection of electric circuits pertaining to the distribution of electric energy. The modernization of the current limiting fuses, without silver and copper consumption, for the protection of high voltage electric circuits pertaining to the distribution of electric energy is based on the patent application: A/00131 of 07-02-2013 “Replacement elements for current limiting fuses”. The modernization consists in increasing the efficiency of the construction of high voltage current limiting fuses by completely eliminating scarce silver and copper materials consumption and replacing them with electrochemically protected electrotechnical aluminum, without diminishing the technical performance of the products. At the same time, by using the composite-silicone insulation, the power consuming components, namely the support insulators of replacement elements caps will be eliminated. By using the composite-silicone insulation for the support insulators with a leakage path that is higher in comparison to the existing insulators of the current replacement elements caps, a safe operation in severe environment conditions is provided, in accordance with IEC 60282-1 /5.16/.
{"title":"New solutions for carrying out high voltage fuses for the protection of grids containing power transformers","authors":"M. Duta, S. Vlase, N. Anoaica, V. Voicu, D. Iovan, A. Benea, C. Salceanu, C. Dobrea","doi":"10.1109/ICATE.2014.6972666","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972666","url":null,"abstract":"This article presents the result of the research carried out for the modernization of the constructive solutions for classic current limiting fuses defined in IEC 60282-1 /2009 used for the protection of electric circuits pertaining to the distribution of electric energy. The modernization of the current limiting fuses, without silver and copper consumption, for the protection of high voltage electric circuits pertaining to the distribution of electric energy is based on the patent application: A/00131 of 07-02-2013 “Replacement elements for current limiting fuses”. The modernization consists in increasing the efficiency of the construction of high voltage current limiting fuses by completely eliminating scarce silver and copper materials consumption and replacing them with electrochemically protected electrotechnical aluminum, without diminishing the technical performance of the products. At the same time, by using the composite-silicone insulation, the power consuming components, namely the support insulators of replacement elements caps will be eliminated. By using the composite-silicone insulation for the support insulators with a leakage path that is higher in comparison to the existing insulators of the current replacement elements caps, a safe operation in severe environment conditions is provided, in accordance with IEC 60282-1 /5.16/.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"78 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":"133576807","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.2014.6972637
I. Piroi, E. Spunei, Florina Piroi
This work presents a method to determine rotor oscillations during a three-phased sudden short-circuit test of a synchronous generator. To our best current knowledge, no such similar method is yet published in the technical literature. During the periodic and non-periodic component separation of the three phase currents, it was found that the time difference between the currents' extreme values, for any of the three phase currents, does not have a 10 ms constant value, as in the stationary phase. Investigating why this happens we found that these variations are caused by the rotor oscillations. Certain parameters of a synchronous generator's rotor and of the rotor's oscillations are measured during the sudden three-phased short-circuit test. Based on these readings, with the method presented in this paper, we can compute the rotor's mechanical oscillation amplitudes and the transient process durations. Using the measured values, the equation describing the rotor's mechanical oscillations, independent of its power, can be re-written. Knowledge of the oscillation amplitudes and their durations is necessary for a correct loop control design and in establishing the generator's performance.
{"title":"Experimental measurements of the rotor oscillations in an synchronous generator during the three-phased sudden short-circuit test","authors":"I. Piroi, E. Spunei, Florina Piroi","doi":"10.1109/ICATE.2014.6972637","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972637","url":null,"abstract":"This work presents a method to determine rotor oscillations during a three-phased sudden short-circuit test of a synchronous generator. To our best current knowledge, no such similar method is yet published in the technical literature. During the periodic and non-periodic component separation of the three phase currents, it was found that the time difference between the currents' extreme values, for any of the three phase currents, does not have a 10 ms constant value, as in the stationary phase. Investigating why this happens we found that these variations are caused by the rotor oscillations. Certain parameters of a synchronous generator's rotor and of the rotor's oscillations are measured during the sudden three-phased short-circuit test. Based on these readings, with the method presented in this paper, we can compute the rotor's mechanical oscillation amplitudes and the transient process durations. Using the measured values, the equation describing the rotor's mechanical oscillations, independent of its power, can be re-written. Knowledge of the oscillation amplitudes and their durations is necessary for a correct loop control design and in establishing the generator's performance.","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":"129098906","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.2014.6972593
M. I. Neacă, A. Neaca
This paper proposes a dynamic system based on microcontroller, that generates a three-phase SPWM command, with variable frequency which is needed to an inverter designed to operate at U/f = const. It is presented a original simulation system, whose implementation and testing has allowed the establishment of directions of action necessary for the design of the software for programming the microcontroller. In the research carried out has always been analyzed how external commands can be sent to the microcontroller. There are considered as essential three external prescriptions: the frequency of the three-phase sinusoidal voltage, the maximum voltage to the inverter output and the multiplication factor for frequency of the triangular wave used to generate SPWM modulation.
{"title":"Simulation of a three-phase SPWM command system with microcontroller","authors":"M. I. Neacă, A. Neaca","doi":"10.1109/ICATE.2014.6972593","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972593","url":null,"abstract":"This paper proposes a dynamic system based on microcontroller, that generates a three-phase SPWM command, with variable frequency which is needed to an inverter designed to operate at U/f = const. It is presented a original simulation system, whose implementation and testing has allowed the establishment of directions of action necessary for the design of the software for programming the microcontroller. In the research carried out has always been analyzed how external commands can be sent to the microcontroller. There are considered as essential three external prescriptions: the frequency of the three-phase sinusoidal voltage, the maximum voltage to the inverter output and the multiplication factor for frequency of the triangular wave used to generate SPWM modulation.","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":"134329167","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.2014.6972689
A. Tudosie
This paper deals with a jet-engine speed control system (SCS), which operates during the aircraft take-off, when the cooling fluid injection system (CFIS) is also active. In order to evaluate the SCS, from its stability and quality point of view, one has established its new mathematical model and transfer function and one has also performed some computer simulations, using experimental data for an existing jet engine, VK-1A. The studies were performed for two different situations, concerning the cooling fluid injection pump: independent (electrically driven pump), or driven by the engine's shaft. Simulations results (system step response) were presented for both situations. Further studies should be extended for multi-spool engines.
{"title":"Speed control system for a jet-engine with fluid injection into its compressor","authors":"A. Tudosie","doi":"10.1109/ICATE.2014.6972689","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972689","url":null,"abstract":"This paper deals with a jet-engine speed control system (SCS), which operates during the aircraft take-off, when the cooling fluid injection system (CFIS) is also active. In order to evaluate the SCS, from its stability and quality point of view, one has established its new mathematical model and transfer function and one has also performed some computer simulations, using experimental data for an existing jet engine, VK-1A. The studies were performed for two different situations, concerning the cooling fluid injection pump: independent (electrically driven pump), or driven by the engine's shaft. Simulations results (system step response) were presented for both situations. Further studies should be extended for multi-spool engines.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"89 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":"125521438","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.2014.6972677
M. Nicolae, Alexandru Tudorascu, P. Nicolae, R. Saray, Briant Kall, G. Rambolamanana
The paper deals with a comparison between the energy received by solar panels in two different facilities. The study is based on the design of two positioning systems and the amount of energy received by them. The manufacturing of the mobile support is treated first, then the design of the stationary support is presented. At the next stage, one realized the design of the control circuit, managing the system in an automatic way. The heart of the system is a microcontroller from the ATMEGA8 family. ISP (In-System Programming) is used for programming the controller and the code is written in C language. The interfaces for the light sensors, the position sensors and the power circuit are used in order to drive the motor. The positioning of the mobile support is provided by a dedicated program, in order to avoid the overlapping between different parts of the mechanical system's moving elements. Finally, some power measurements, tests, monitoring and diagnosis for these two facilities were performed.
本文对两种不同设施的太阳能电池板接收的能量进行了比较。本研究是基于两种定位系统的设计和它们所接收的能量。首先讨论了移动支架的制造，然后介绍了固定支架的设计。在第二阶段，实现了控制电路的设计，实现了系统的自动管理。该系统的核心是ATMEGA8系列的微控制器。采用ISP (in - system Programming)对控制器进行编程，代码采用C语言编写。使用光传感器、位置传感器和电源电路的接口来驱动电机。移动支架的定位由专门的程序提供，以避免机械系统运动元件的不同部分之间的重叠。最后，对这两种设备进行了功率测量、测试、监测和诊断。
{"title":"Optimization design of photovoltaic systems and improving their energy efficiency through a novel technology installation of the support","authors":"M. Nicolae, Alexandru Tudorascu, P. Nicolae, R. Saray, Briant Kall, G. Rambolamanana","doi":"10.1109/ICATE.2014.6972677","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972677","url":null,"abstract":"The paper deals with a comparison between the energy received by solar panels in two different facilities. The study is based on the design of two positioning systems and the amount of energy received by them. The manufacturing of the mobile support is treated first, then the design of the stationary support is presented. At the next stage, one realized the design of the control circuit, managing the system in an automatic way. The heart of the system is a microcontroller from the ATMEGA8 family. ISP (In-System Programming) is used for programming the controller and the code is written in C language. The interfaces for the light sensors, the position sensors and the power circuit are used in order to drive the motor. The positioning of the mobile support is provided by a dedicated program, in order to avoid the overlapping between different parts of the mechanical system's moving elements. Finally, some power measurements, tests, monitoring and diagnosis for these two facilities were performed.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"2 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":"129448502","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.2014.6972680
E. Spunei, I. Piroi, C. Muscai, Florina Piroi
We present in this paper a software module for the diagnosis of Automatic Bloc Signaling installation failures in situations where the train open line figures as blocked, although it is, in reality, free. The software module created by us, LCOBla, is designed for the use of maintenance staff specialized in Signals, Centralizations, Blocking (SCB) at the Romanian Railroad Company (CFR). LCOBla allows a quick and correct design of the failure causes associated with these kinds of signaling and contributes to the maintenance staff performance. Fast failure remedy improves train traffic flow and reduces train delay times. The LCOBla software module uses the diagnosis chart created for these kinds of failures, which, in turn, is based on the actual block schemes and on technical recommendations for these types of installations. The module is one of a series of modules designed to diagnose each failure type, for the various railway traffic safety installation types.
{"title":"Automatic block signaling installation failure diagnosis with LCOBla","authors":"E. Spunei, I. Piroi, C. Muscai, Florina Piroi","doi":"10.1109/ICATE.2014.6972680","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972680","url":null,"abstract":"We present in this paper a software module for the diagnosis of Automatic Bloc Signaling installation failures in situations where the train open line figures as blocked, although it is, in reality, free. The software module created by us, LCOBla, is designed for the use of maintenance staff specialized in Signals, Centralizations, Blocking (SCB) at the Romanian Railroad Company (CFR). LCOBla allows a quick and correct design of the failure causes associated with these kinds of signaling and contributes to the maintenance staff performance. Fast failure remedy improves train traffic flow and reduces train delay times. The LCOBla software module uses the diagnosis chart created for these kinds of failures, which, in turn, is based on the actual block schemes and on technical recommendations for these types of installations. The module is one of a series of modules designed to diagnose each failure type, for the various railway traffic safety installation types.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"24 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":"133583226","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.2014.6972670
L. Rakotomalala, Z. Randriamanantany, G. Chiriac, D. Lucache
Due to their lumen per watt efficiency, the HID lamps are wide used especially in the outdoor applications, but also in indoor industrial or commercial ones. The ballasts necessary for their normal operation could be magnetic or electronic and in the last decade we assist to a long debate on which is a better option. The dimming capabilities are one of the most claimed advantages of the electronic ballasts. But, in the last years, several lower cost solutions for getting dimmability with magnetic ballasts have been reconsidered. In this paper, the possibility to dim lamps trough the voltage amplitude modulation by means an autotransformer is explored. This solution can be cheaper, robust and most suited for the low budget Africa's lighting systems. Several experimental tests have been performed on two type of 250W HID lamps, a High Pressure Sodium (HPS) and a Metal Halide (MH), operated by a Very-Low-Loss (VLL) magnetic ballast. The range of the voltage modulation has been from 160V to 250V and the power consumption, the light output and the harmonics content have been recorded. The results confirm once again the validity of this proposed solution. The energy-saving per lamp by dimming to 160V is about 55 % for HPS lamp and 52.72% for MH lamp.
{"title":"HID lamps dimming in the public lighting installations dominated by magnetic ballasts","authors":"L. Rakotomalala, Z. Randriamanantany, G. Chiriac, D. Lucache","doi":"10.1109/ICATE.2014.6972670","DOIUrl":"https://doi.org/10.1109/ICATE.2014.6972670","url":null,"abstract":"Due to their lumen per watt efficiency, the HID lamps are wide used especially in the outdoor applications, but also in indoor industrial or commercial ones. The ballasts necessary for their normal operation could be magnetic or electronic and in the last decade we assist to a long debate on which is a better option. The dimming capabilities are one of the most claimed advantages of the electronic ballasts. But, in the last years, several lower cost solutions for getting dimmability with magnetic ballasts have been reconsidered. In this paper, the possibility to dim lamps trough the voltage amplitude modulation by means an autotransformer is explored. This solution can be cheaper, robust and most suited for the low budget Africa's lighting systems. Several experimental tests have been performed on two type of 250W HID lamps, a High Pressure Sodium (HPS) and a Metal Halide (MH), operated by a Very-Low-Loss (VLL) magnetic ballast. The range of the voltage modulation has been from 160V to 250V and the power consumption, the light output and the harmonics content have been recorded. The results confirm once again the validity of this proposed solution. The energy-saving per lamp by dimming to 160V is about 55 % for HPS lamp and 52.72% for MH lamp.","PeriodicalId":327050,"journal":{"name":"2014 International Conference on Applied and Theoretical Electricity (ICATE)","volume":"38 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":"133842228","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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