Pub Date : 2014-07-24DOI: 10.1109/AICERA.2014.6908176
Babitha T. Abraham, A. Benny
Multilevel Inverter is an array of power semiconductors and capacitors that allow the generation of a high quality load voltage. But it requires greater number of power semiconductor switches with increase in number of levels. In this paper, three phase hybrid topology of multilevel inverter is used to reduce the number of switching devices in the entire converter system. The proposed topology is a hybrid of cascaded H-bridge multilevel inverter (CHBMLI) and neutral point clamped inverter multilevel inverter (NPCMLI) so as to obtain seven level output in each phase. Third harmonic injection is adopted to increase the line to line voltage. Asymmetric dc bus voltage ratio is used to increase the number of levels. The main objective of this hybridised structure is to increase the number of levels with reduced number of switches.
{"title":"Asymmetric multilevel hybrid inverter with reduced number of switches","authors":"Babitha T. Abraham, A. Benny","doi":"10.1109/AICERA.2014.6908176","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908176","url":null,"abstract":"Multilevel Inverter is an array of power semiconductors and capacitors that allow the generation of a high quality load voltage. But it requires greater number of power semiconductor switches with increase in number of levels. In this paper, three phase hybrid topology of multilevel inverter is used to reduce the number of switching devices in the entire converter system. The proposed topology is a hybrid of cascaded H-bridge multilevel inverter (CHBMLI) and neutral point clamped inverter multilevel inverter (NPCMLI) so as to obtain seven level output in each phase. Third harmonic injection is adopted to increase the line to line voltage. Asymmetric dc bus voltage ratio is used to increase the number of levels. The main objective of this hybridised structure is to increase the number of levels with reduced number of switches.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128195370","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908174
Riya Philip, C. Sreeja
Nowadays, low Power Factor (PF) is a serious problem that gained more importance in power electronics area. In this paper, single phase PFC using Buck-Boost circuit topology under linearization voltage control is realized. Here the nonlinear load considered is the diode bridge rectifier, and a Buck-Boost converter is connected to its back end for PFC. The switching of buck-boost converter is done by comparing the dc control signal with a saw tooth wave and its switching frequency is set to 100 kHz. The simulation analyses are carried out in Matlab/Simulink software. The effect of PFC Buck-Boost circuit on PF and the sinusoidal nature of line current are analyzed by the simulation results. Its effectiveness is experimentally validated by means of a self designed prototype. Experimental results show that, Buck-Boost circuit topology have an excellent ability for PFC. It makes the supply voltage and current in phase to each other and thus approximate the PF to unity.
{"title":"Single phase PFC using Buck-Boost converter","authors":"Riya Philip, C. Sreeja","doi":"10.1109/AICERA.2014.6908174","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908174","url":null,"abstract":"Nowadays, low Power Factor (PF) is a serious problem that gained more importance in power electronics area. In this paper, single phase PFC using Buck-Boost circuit topology under linearization voltage control is realized. Here the nonlinear load considered is the diode bridge rectifier, and a Buck-Boost converter is connected to its back end for PFC. The switching of buck-boost converter is done by comparing the dc control signal with a saw tooth wave and its switching frequency is set to 100 kHz. The simulation analyses are carried out in Matlab/Simulink software. The effect of PFC Buck-Boost circuit on PF and the sinusoidal nature of line current are analyzed by the simulation results. Its effectiveness is experimentally validated by means of a self designed prototype. Experimental results show that, Buck-Boost circuit topology have an excellent ability for PFC. It makes the supply voltage and current in phase to each other and thus approximate the PF to unity.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130712769","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908287
R. Mini, K. Anu, M. Dinesh
The stator flux and electromagnetic torque are directly controlled in a DTC system using space vector modulation technique. In DTC, torque and flux ripples increases at low speeds. A DTC-SVM induction motor drive at very low speeds is investigated here and High Frequency Signal Injection (HFSI) method is adopted to mitigate the low speed issues. In this method a sinusoidal wave of small amplitude and high frequency is injected along with the PI controller output of DTC-SVM. HFSI increases the switching frequency of SVM during low speed operation. This technique reduces torque ripple, acoustic noise, and gives excellent dynamic and steady state performance. The performance of DTC-SVM and DTC-SVM with HFSI at low speed is analyzed through simulation using matlab/simulink package. The results verify the merits of the DTC-SVM using HF injection technique with respect to DTC-SVM technique at very low speeds.
{"title":"HFSI — A promising solution to very low speed issues in DTC-SVM induction motor drive","authors":"R. Mini, K. Anu, M. Dinesh","doi":"10.1109/AICERA.2014.6908287","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908287","url":null,"abstract":"The stator flux and electromagnetic torque are directly controlled in a DTC system using space vector modulation technique. In DTC, torque and flux ripples increases at low speeds. A DTC-SVM induction motor drive at very low speeds is investigated here and High Frequency Signal Injection (HFSI) method is adopted to mitigate the low speed issues. In this method a sinusoidal wave of small amplitude and high frequency is injected along with the PI controller output of DTC-SVM. HFSI increases the switching frequency of SVM during low speed operation. This technique reduces torque ripple, acoustic noise, and gives excellent dynamic and steady state performance. The performance of DTC-SVM and DTC-SVM with HFSI at low speed is analyzed through simulation using matlab/simulink package. The results verify the merits of the DTC-SVM using HF injection technique with respect to DTC-SVM technique at very low speeds.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133961047","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908275
Saikat Sahoo, Senggam Wakhet, B. Champaty, Jobin Jose, Sai S. Sagiri, K. Pal
Electrical impedance measurement of the biological samples has evolved as a new field in biomedical engineering. This is due to the fact that the electrical properties of the biological samples change considerably during diseased and healthy conditions. Unfortunately, the devices available in the market are bulky and are quite costly. In this study, we report the development of a portable, standalone, multi-frequency (50 Hz-10 KHz) impedance measurement device with acceptable accuracy and resolution for in vitro impedance measurement of the cells.
{"title":"Development of portable standalone impedance measuring device for in vitro applications","authors":"Saikat Sahoo, Senggam Wakhet, B. Champaty, Jobin Jose, Sai S. Sagiri, K. Pal","doi":"10.1109/AICERA.2014.6908275","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908275","url":null,"abstract":"Electrical impedance measurement of the biological samples has evolved as a new field in biomedical engineering. This is due to the fact that the electrical properties of the biological samples change considerably during diseased and healthy conditions. Unfortunately, the devices available in the market are bulky and are quite costly. In this study, we report the development of a portable, standalone, multi-frequency (50 Hz-10 KHz) impedance measurement device with acceptable accuracy and resolution for in vitro impedance measurement of the cells.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"225 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132641087","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908193
A. Vipin, S. George
Permanent Magnet Synchronous Motors (PMSM) are good option for electric vehicles, hybrid electric vehicles and used for many industrial, aerospace and domestic applications. This paper presents hardware implementation of PMSM drive system without using any position sensor. An open loop control is implemented to operate PMSM at various speeds. Discussed basic theory of space vector PWM for generating sinusoidal voltage to motor and realised with 16 bit microcontroller. A three phase inverter is designed and implemented to control 1 KW outer rotor PMSM. The motor is started and operated at various speeds by changing the inverter output frequency. Starting and running characteristics of PMSM in open loop is observed and discussed.
{"title":"Hardware implementation of space vector PWM control of Permanent Magnet Synchronous Motor","authors":"A. Vipin, S. George","doi":"10.1109/AICERA.2014.6908193","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908193","url":null,"abstract":"Permanent Magnet Synchronous Motors (PMSM) are good option for electric vehicles, hybrid electric vehicles and used for many industrial, aerospace and domestic applications. This paper presents hardware implementation of PMSM drive system without using any position sensor. An open loop control is implemented to operate PMSM at various speeds. Discussed basic theory of space vector PWM for generating sinusoidal voltage to motor and realised with 16 bit microcontroller. A three phase inverter is designed and implemented to control 1 KW outer rotor PMSM. The motor is started and operated at various speeds by changing the inverter output frequency. Starting and running characteristics of PMSM in open loop is observed and discussed.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132289586","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908242
R. Dhar, S. Bindu, S. George, P. C. Saroj, Archana Sharma
Marx generator is an impulse source used for testing of various equipments. High voltage DC source is input to Marx generator. Traditionally, DC sources used for Marx generator were of large size but now due to advancement in solid state devices it is possible to reduce size and weight of DC source. This paper explains the designing and simulation of 30 kV solid state DC source to Marx generator. It makes use of zero current switching - series resonant (ZCS-SR) full - bridge topology with high frequency transformer and six stage voltage multiplier circuit. For switching purpose MOSFET is used. Effect of resistive and capacitive load on output voltage is analyzed.
{"title":"Design and simulation of 30 kv solid state DC source","authors":"R. Dhar, S. Bindu, S. George, P. C. Saroj, Archana Sharma","doi":"10.1109/AICERA.2014.6908242","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908242","url":null,"abstract":"Marx generator is an impulse source used for testing of various equipments. High voltage DC source is input to Marx generator. Traditionally, DC sources used for Marx generator were of large size but now due to advancement in solid state devices it is possible to reduce size and weight of DC source. This paper explains the designing and simulation of 30 kV solid state DC source to Marx generator. It makes use of zero current switching - series resonant (ZCS-SR) full - bridge topology with high frequency transformer and six stage voltage multiplier circuit. For switching purpose MOSFET is used. Effect of resistive and capacitive load on output voltage is analyzed.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129256229","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908248
K. J. Mohan, Riboy Cheriyan
In this paper a new high speed address generator for the dynamic modulation scheme supportive WiMAX deinterleaver design is proposed. The WiMAX can be both fixed and mobile, in this work the mobile WiMAX is given more importance. The mobile WiMAX uses interleaving and deinterleaving techniques in its transreceiver for eliminating the transmission errors. The WiMAX supports QPSK, 16-QAM and 64-QAM modulation schemes for establishing a connection between subscriber and base stations. Deinterleaver has to produce the addresses for these different modulation schemes by performing the inverse operation of interleaving. The address generator in the deinterleaver hinders the performance of the receiver section of the WiMAX system so it has to be optimized to improve the overall performance. In this paper a new ASIC based design has been proposed for the address generator and the design is been modelled in VHDL.
{"title":"High speed address generating design for the dynamic modulation scheme supportive WiMAX deinterleaver","authors":"K. J. Mohan, Riboy Cheriyan","doi":"10.1109/AICERA.2014.6908248","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908248","url":null,"abstract":"In this paper a new high speed address generator for the dynamic modulation scheme supportive WiMAX deinterleaver design is proposed. The WiMAX can be both fixed and mobile, in this work the mobile WiMAX is given more importance. The mobile WiMAX uses interleaving and deinterleaving techniques in its transreceiver for eliminating the transmission errors. The WiMAX supports QPSK, 16-QAM and 64-QAM modulation schemes for establishing a connection between subscriber and base stations. Deinterleaver has to produce the addresses for these different modulation schemes by performing the inverse operation of interleaving. The address generator in the deinterleaver hinders the performance of the receiver section of the WiMAX system so it has to be optimized to improve the overall performance. In this paper a new ASIC based design has been proposed for the address generator and the design is been modelled in VHDL.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"46 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124090176","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908184
V. Hema, R. Dhanalakshmi
The proposed paper presents a Hybrid AC-DC microgrid to chop the process of multiple conversions in an individual AC microgrid or DC microgrid. The proposed hybrid microgrid compose of both AC microgrid and DC microgrid connected together by multilevel inverter. This paper concentrates on developing a control system for the hybrid AC-DC microgrid to manage power flows, which is more difficult than previously developed systems only for AC microgrid or DC microgrid. The objective is then to makeup a co-ordinated control system for power sharing within the sources in the hybrid AC-DC microgrid in proportion to the power ratings. The droop control technique is presented in this paper to control the hybrid microgrid. The droop control concept uses a suitable normalization technique for combining both the subgrids. The co-ordinated operation of DC and AC sources and multilevel inverter are investigated. Analysis of power sharing on hybrid AC-DC microgrid is done using MATLAB/SIMULINK.
{"title":"Analysis of power sharing on hybrid AC-DC microgrid","authors":"V. Hema, R. Dhanalakshmi","doi":"10.1109/AICERA.2014.6908184","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908184","url":null,"abstract":"The proposed paper presents a Hybrid AC-DC microgrid to chop the process of multiple conversions in an individual AC microgrid or DC microgrid. The proposed hybrid microgrid compose of both AC microgrid and DC microgrid connected together by multilevel inverter. This paper concentrates on developing a control system for the hybrid AC-DC microgrid to manage power flows, which is more difficult than previously developed systems only for AC microgrid or DC microgrid. The objective is then to makeup a co-ordinated control system for power sharing within the sources in the hybrid AC-DC microgrid in proportion to the power ratings. The droop control technique is presented in this paper to control the hybrid microgrid. The droop control concept uses a suitable normalization technique for combining both the subgrids. The co-ordinated operation of DC and AC sources and multilevel inverter are investigated. Analysis of power sharing on hybrid AC-DC microgrid is done using MATLAB/SIMULINK.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123758269","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908160
Shelma George, R. V. Chacko, A. Mathew
Modelling of Electric Vehicle power train is analysed to evaluate the energy flow between electrical and mechanical sub systems. The indigenous platform SEQUEL gives more user configurability and new user element support for offline simulation. State-of-the-art real-time simulation facilitates the controller development and evaluation before making the plant prototype of system like EV. Because of the high frequency switching in power converter/inverter and due to complex motor dynamics detailed simulation of EV power train need high computation with simulation delta time of the order of 1-2 micro sec. This is practical in offline simulation where as presently available real-time simulators can do simulation in 50-100 micro seconds only. So the concept of average modelling is introduced in EV sub-systems to derive appropriate models to implement real time simulation.
{"title":"Off-line and real-time simulation Modelling of Electric Vehicle power train","authors":"Shelma George, R. V. Chacko, A. Mathew","doi":"10.1109/AICERA.2014.6908160","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908160","url":null,"abstract":"Modelling of Electric Vehicle power train is analysed to evaluate the energy flow between electrical and mechanical sub systems. The indigenous platform SEQUEL gives more user configurability and new user element support for offline simulation. State-of-the-art real-time simulation facilitates the controller development and evaluation before making the plant prototype of system like EV. Because of the high frequency switching in power converter/inverter and due to complex motor dynamics detailed simulation of EV power train need high computation with simulation delta time of the order of 1-2 micro sec. This is practical in offline simulation where as presently available real-time simulators can do simulation in 50-100 micro seconds only. So the concept of average modelling is introduced in EV sub-systems to derive appropriate models to implement real time simulation.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"64 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122977708","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 : 2014-07-24DOI: 10.1109/AICERA.2014.6908215
R. Femi, Shibu Clement, Anita Agrawal, A. Prince
This paper presents, a cross tied array of electrostatically actuated Micro-electromechanical system (MEMS) switches for AC circuit breaking applications. Conventional electromagnetic circuit breakers and power electronics circuit breakers are studied and simulated to understand their performance characteristics. Energy density of Electrostatic MEMS switch and electromagnetic MEMS switch are analyzed to achieve miniaturization in size. Cross tied m×n MEMS switch array has been proposed. 230V AC system is considered for simulation and comparison study. The simulated result of proposed MEMS switch array configuration has been compared with conventional switches. The comparative study shows that the proposed switch array gives better performance in terms of voltage drop, leakage current and power loss.
{"title":"Cross tied array of electro-statically actuated micro-electromechanical switches for AC circuit breaking applications","authors":"R. Femi, Shibu Clement, Anita Agrawal, A. Prince","doi":"10.1109/AICERA.2014.6908215","DOIUrl":"https://doi.org/10.1109/AICERA.2014.6908215","url":null,"abstract":"This paper presents, a cross tied array of electrostatically actuated Micro-electromechanical system (MEMS) switches for AC circuit breaking applications. Conventional electromagnetic circuit breakers and power electronics circuit breakers are studied and simulated to understand their performance characteristics. Energy density of Electrostatic MEMS switch and electromagnetic MEMS switch are analyzed to achieve miniaturization in size. Cross tied m×n MEMS switch array has been proposed. 230V AC system is considered for simulation and comparison study. The simulated result of proposed MEMS switch array configuration has been compared with conventional switches. The comparative study shows that the proposed switch array gives better performance in terms of voltage drop, leakage current and power loss.","PeriodicalId":425226,"journal":{"name":"2014 Annual International Conference on Emerging Research Areas: Magnetics, Machines and Drives (AICERA/iCMMD)","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2014-07-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117062432","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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