Pub Date : 2004-11-29DOI: 10.1109/PECON.2004.1461645
H. Rahman, S. Majid, Lee Wan Zhen, Che Noraimy Che Aziz
This paper presents the methodology and opportunity in implementing energy conservation and efficiency in a medium scale industry. A user-friendly package was developed to assist the energy auditor in analyzing the data collected to determine the potential of energy efficiency and conservation. The software covers the analysis on motor, transformer, lighting, cable sizing, air-conditioning and power factor improvement. The analysis gives a straightforward cost comparison between the capital cost, running cost and the payback period. The software was developed using Microsoft Visual Basic 6.0.
{"title":"Energy efficiency and conservation study for a medium scale industry in Malaysia","authors":"H. Rahman, S. Majid, Lee Wan Zhen, Che Noraimy Che Aziz","doi":"10.1109/PECON.2004.1461645","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461645","url":null,"abstract":"This paper presents the methodology and opportunity in implementing energy conservation and efficiency in a medium scale industry. A user-friendly package was developed to assist the energy auditor in analyzing the data collected to determine the potential of energy efficiency and conservation. The software covers the analysis on motor, transformer, lighting, cable sizing, air-conditioning and power factor improvement. The analysis gives a straightforward cost comparison between the capital cost, running cost and the payback period. The software was developed using Microsoft Visual Basic 6.0.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121872477","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461629
P. C. Tan, Z. Salam
This paper presents a new single-phase two-wire hybrid active power filter configuration that interconnects a passive high-pass filter in parallel with an active power filter and a photovoltaic system. The proposed configuration can improves the filtering performance of the conventional active power filter, as well as simultaneously supply the power from the photovoltaic arrays to the load and utility. Furthermore, the derivation of arrays to the load and utility. Furthermore, the derivation of extension p-q theorem. This paper describes the proposed hybrid active power filter with photovoltaic system. It primarily focuses on the power circuit control system and the compensation current reference derivation. The proposed system effectively filters harmonics under 1 kHz but also higher frequency to achieve wideband harmonics compensation. The THD of source current is reduced from 76.83 % to 3.21 %. The simulation results that verify the theoretical predictions of the proposed configuration is presented.
{"title":"A new single-phase two-wire hybrid active power filter using extension p-q theorem for photovoltaic application","authors":"P. C. Tan, Z. Salam","doi":"10.1109/PECON.2004.1461629","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461629","url":null,"abstract":"This paper presents a new single-phase two-wire hybrid active power filter configuration that interconnects a passive high-pass filter in parallel with an active power filter and a photovoltaic system. The proposed configuration can improves the filtering performance of the conventional active power filter, as well as simultaneously supply the power from the photovoltaic arrays to the load and utility. Furthermore, the derivation of arrays to the load and utility. Furthermore, the derivation of extension p-q theorem. This paper describes the proposed hybrid active power filter with photovoltaic system. It primarily focuses on the power circuit control system and the compensation current reference derivation. The proposed system effectively filters harmonics under 1 kHz but also higher frequency to achieve wideband harmonics compensation. The THD of source current is reduced from 76.83 % to 3.21 %. The simulation results that verify the theoretical predictions of the proposed configuration is presented.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115323949","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461612
N. A. Abu Bakar, A. Mohamed, M. Ismail
Voltage sags are recognized as the most important power quality problem, which may cause sensitive equipments to trip, thus causing a major economic impact. Voltage sag analysis is usually , required to determine the voltage sag characteristics, the likelihood of a voltage sag occurrence and areas of vulnerability in power distribution systems. This paper presents a software development of a voltage sag analysis tool using the PSS engine application program interface library by Power Technologies Incorporation, Microsoft C++ and Visual BASIC. The objective is to develop a dedicated software for voltage sag analysis which automates the process of creating sliding nodes and fault analysis which is not available in the existing commercial power system analysis packages. An important feature included in the program is the short circuit analysis which incorporates multiple sliding faults analysis. Results are presented in tabular form and stored in exchangeable file format. The program has been tested on a real power distribution network and the results are satisfactory.
{"title":"Software development of a voltage sag analysis tool for power quality study","authors":"N. A. Abu Bakar, A. Mohamed, M. Ismail","doi":"10.1109/PECON.2004.1461612","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461612","url":null,"abstract":"Voltage sags are recognized as the most important power quality problem, which may cause sensitive equipments to trip, thus causing a major economic impact. Voltage sag analysis is usually , required to determine the voltage sag characteristics, the likelihood of a voltage sag occurrence and areas of vulnerability in power distribution systems. This paper presents a software development of a voltage sag analysis tool using the PSS engine application program interface library by Power Technologies Incorporation, Microsoft C++ and Visual BASIC. The objective is to develop a dedicated software for voltage sag analysis which automates the process of creating sliding nodes and fault analysis which is not available in the existing commercial power system analysis packages. An important feature included in the program is the short circuit analysis which incorporates multiple sliding faults analysis. Results are presented in tabular form and stored in exchangeable file format. The program has been tested on a real power distribution network and the results are satisfactory.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117065602","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461622
Y. Yusof, S. Sayuti, M. A. ABDUL LATIF, M. Wanik
This paper presents an approach to model and simulate a maximum power point tracker (MPPT) of photovoltaic (PV) system for battery charging application. Firstly, a simulation of Shell SM50-H PV module current-voltage (I-V) and power-voltage (P-V) characteristics at various insolation and temperature levels have been carried out using Matlab software. Next, the incremental conductance algorithm is applied for maximum power point (MPP) tracking purpose, which is developed using C programming. This algorithm is selected due to its ability to withstand against any parameter variation and having a very high efficiency. As a result, by variation of the temperature and the insolation, the algorithm still managed to track the MPP successfully. Finally, a model of a boost converter is constructed using Matlab/Simulink, particularly with great utilization of the power system blockset, (PSB), in order to verify the performance of proposed MPPT system. MPPT controlling process is developed using a simple voltage based MPPT that is controlled by a microcontroller-based unit to drive the MOSFET power switch. As for the consequences, this technique performance tends to give significant efficiency, in addition, it is cost saving and reliable.
{"title":"Modeling and simulation of maximum power point tracker for photovoltaic system","authors":"Y. Yusof, S. Sayuti, M. A. ABDUL LATIF, M. Wanik","doi":"10.1109/PECON.2004.1461622","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461622","url":null,"abstract":"This paper presents an approach to model and simulate a maximum power point tracker (MPPT) of photovoltaic (PV) system for battery charging application. Firstly, a simulation of Shell SM50-H PV module current-voltage (I-V) and power-voltage (P-V) characteristics at various insolation and temperature levels have been carried out using Matlab software. Next, the incremental conductance algorithm is applied for maximum power point (MPP) tracking purpose, which is developed using C programming. This algorithm is selected due to its ability to withstand against any parameter variation and having a very high efficiency. As a result, by variation of the temperature and the insolation, the algorithm still managed to track the MPP successfully. Finally, a model of a boost converter is constructed using Matlab/Simulink, particularly with great utilization of the power system blockset, (PSB), in order to verify the performance of proposed MPPT system. MPPT controlling process is developed using a simple voltage based MPPT that is controlled by a microcontroller-based unit to drive the MOSFET power switch. As for the consequences, this technique performance tends to give significant efficiency, in addition, it is cost saving and reliable.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122927959","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461618
L. S. Toh, Z. Salam, M. Z. Ramli
This paper presents a closed loop controller for bidirectional high-frequency link inverter. Deadbeat control is adopted to achieve fast dynamic response. The controller consists of inner current loop and outer voltage loop. To improve overall performance of the system, additional decoupling networks are employed. Output voltage decoupling network is included to improve the response of current loop; while load current decoupling network is used to increase the robustness of the inverter towards load variation. Simulation results are presented for the closed loop system under linear and nonlinear loads. It is shown that the control method provides good dynamic response with low total harmonic distortion, even under full-bridge rectifier loads.
{"title":"Analysis and design of a closed loop controller for bidirectional high-frequency link inverter","authors":"L. S. Toh, Z. Salam, M. Z. Ramli","doi":"10.1109/PECON.2004.1461618","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461618","url":null,"abstract":"This paper presents a closed loop controller for bidirectional high-frequency link inverter. Deadbeat control is adopted to achieve fast dynamic response. The controller consists of inner current loop and outer voltage loop. To improve overall performance of the system, additional decoupling networks are employed. Output voltage decoupling network is included to improve the response of current loop; while load current decoupling network is used to increase the robustness of the inverter towards load variation. Simulation results are presented for the closed loop system under linear and nonlinear loads. It is shown that the control method provides good dynamic response with low total harmonic distortion, even under full-bridge rectifier loads.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121317368","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461660
T. Rahman, S. Rahim, I. Musirin
Recent years, the number of embedded generators installed in distribution system has been increasing in many parts of the world. Depending on their operating characteristics and locations, embedded generators could significantly affect the voltage profile, network losses and fault level in a distribution system. This paper presents a new technique for determining optimal allocation and sizing of embedded generator in a distribution system. Sensitivity indices based on voltage stability improvement with respect to change in injected active and reactive power at a load bus were derived and used to identify the suitable location for the embedded generators. In order to determine the optimal output of the embedded generators, an evolutionary programming optimization technique was developed with an objective to minimize the distribution losses while satisfying the voltage constraint in the system. The proposed technique was tested on the 69 bus distribution system and the results shown a significant reduction in distribution losses and voltage profile improvement in the system with the implementation of the embedded generation at the suitable location and optimal sizing.
{"title":"Optimal allocation and sizing of embedded generators","authors":"T. Rahman, S. Rahim, I. Musirin","doi":"10.1109/PECON.2004.1461660","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461660","url":null,"abstract":"Recent years, the number of embedded generators installed in distribution system has been increasing in many parts of the world. Depending on their operating characteristics and locations, embedded generators could significantly affect the voltage profile, network losses and fault level in a distribution system. This paper presents a new technique for determining optimal allocation and sizing of embedded generator in a distribution system. Sensitivity indices based on voltage stability improvement with respect to change in injected active and reactive power at a load bus were derived and used to identify the suitable location for the embedded generators. In order to determine the optimal output of the embedded generators, an evolutionary programming optimization technique was developed with an objective to minimize the distribution losses while satisfying the voltage constraint in the system. The proposed technique was tested on the 69 bus distribution system and the results shown a significant reduction in distribution losses and voltage profile improvement in the system with the implementation of the embedded generation at the suitable location and optimal sizing.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126363629","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461632
M. Sahid, N. Azli, N. Muhammad
Power factor correction (PFC) circuit using boost converter for low power applications are developed and analyzed in this work. Average current mode control is utilized in this work to control the circuit in the closed loop system. Simulation is done for the boost PFC circuit to validate the designed parameters. Furthermore, an experimental circuit is developed to verify and compare the results with the simulation. The frequency spectrum of the input current is then compared with the EN/IEC61000-2-3 standard on harmonic distortion. The dynamic response of the input current and output voltage are discusses as well. A 500 W output load is first chosen to illustrate the performances of the circuit. Several values of output load and input voltage would conclude the overall performance of the circuit.
{"title":"A comparative study on the performances of the boost PFC circuit","authors":"M. Sahid, N. Azli, N. Muhammad","doi":"10.1109/PECON.2004.1461632","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461632","url":null,"abstract":"Power factor correction (PFC) circuit using boost converter for low power applications are developed and analyzed in this work. Average current mode control is utilized in this work to control the circuit in the closed loop system. Simulation is done for the boost PFC circuit to validate the designed parameters. Furthermore, an experimental circuit is developed to verify and compare the results with the simulation. The frequency spectrum of the input current is then compared with the EN/IEC61000-2-3 standard on harmonic distortion. The dynamic response of the input current and output voltage are discusses as well. A 500 W output load is first chosen to illustrate the performances of the circuit. Several values of output load and input voltage would conclude the overall performance of the circuit.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127738613","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461661
M. Afendi, M. Piah, A. Darus
Environmental pollution can cause the insulator material to become progressively coated with dirt and chemicals in the long run. In the presence of wet atmospheric conditions, the leakage current flows due to the development of conducting path across the insulator surface. The level of leakage current depends on the surface wetting and the degree of electrolyte contamination as well as the environmental factors. An analytical approach based on dimensional analysis technique is applied to develop a mathematical model of leakage current in correlation with the environmental stresses. In order to verify the developed model, an inclined-plane tracking test is conducted on the polymeric insulating materials. The experimental work is carried out by measuring the magnitude of surface leakage current at different levels of contamination. Simulation results of the model have shown good agreement to the experimental results and provide useful information on describing the test condition of the tracking test procedures.
{"title":"Mathematical analysis of leakage current level in correlation with environmental stresses for solid insulating material under tracking test","authors":"M. Afendi, M. Piah, A. Darus","doi":"10.1109/PECON.2004.1461661","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461661","url":null,"abstract":"Environmental pollution can cause the insulator material to become progressively coated with dirt and chemicals in the long run. In the presence of wet atmospheric conditions, the leakage current flows due to the development of conducting path across the insulator surface. The level of leakage current depends on the surface wetting and the degree of electrolyte contamination as well as the environmental factors. An analytical approach based on dimensional analysis technique is applied to develop a mathematical model of leakage current in correlation with the environmental stresses. In order to verify the developed model, an inclined-plane tracking test is conducted on the polymeric insulating materials. The experimental work is carried out by measuring the magnitude of surface leakage current at different levels of contamination. Simulation results of the model have shown good agreement to the experimental results and provide useful information on describing the test condition of the tracking test procedures.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133372928","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461636
A. Ariffin, D. Md Nor, M. Y. Rakob
This paper discusses the advanced combined cycle governor model developed for the KL-MSC island system. The underlying thermodynamic characteristics of the gas turbine are discussed and the simplified mathematical equation governing its behaviour is then described. The various controls are also modelled to account for the actual operation during transient conditions such as islanding. Simulations are then conducted to verify that the model confirms with previous developed model that was verified using field tests.
{"title":"Advanced tandem compound combined cycle governor model for KL-MSC island system","authors":"A. Ariffin, D. Md Nor, M. Y. Rakob","doi":"10.1109/PECON.2004.1461636","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461636","url":null,"abstract":"This paper discusses the advanced combined cycle governor model developed for the KL-MSC island system. The underlying thermodynamic characteristics of the gas turbine are discussed and the simplified mathematical equation governing its behaviour is then described. The various controls are also modelled to account for the actual operation during transient conditions such as islanding. Simulations are then conducted to verify that the model confirms with previous developed model that was verified using field tests.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124031102","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 : 2004-11-29DOI: 10.1109/PECON.2004.1461654
M. M. Kamal, T. Rahman, I. Musirin
This paper presents the application of improved genetic algorithms (IGA) for optimal reactive power planning in loss minimisation scheme. In this study, IGA engine was developed to implement the optimisation of reactive power planning. The selection and steady state elitism combined with the conventional anchor spin techniques are incorporated into the traditional genetic algorithms (GA) for the development of the IGA. In each probing, identical initial population is supplied to the mechanism of IGA and traditional GA in order to have consistency during the initial population. The proposed IGA technique was tested on the IEEE reliability test system (IEEE-RTS), and revealed that the total loss has been significantly reduced. Comparative studies on the results obtained from the IGA with respect to the traditional GA, indicating that IGA outperformed the traditional GA in terms of accuracy and number of iteration. Consecutive efforts can be made to further explore the flexibility and capability of the developed IGA to be implemented in solving other optimisation problems in power system.
{"title":"Application of improved genetic algorithms for loss minimisation in power system","authors":"M. M. Kamal, T. Rahman, I. Musirin","doi":"10.1109/PECON.2004.1461654","DOIUrl":"https://doi.org/10.1109/PECON.2004.1461654","url":null,"abstract":"This paper presents the application of improved genetic algorithms (IGA) for optimal reactive power planning in loss minimisation scheme. In this study, IGA engine was developed to implement the optimisation of reactive power planning. The selection and steady state elitism combined with the conventional anchor spin techniques are incorporated into the traditional genetic algorithms (GA) for the development of the IGA. In each probing, identical initial population is supplied to the mechanism of IGA and traditional GA in order to have consistency during the initial population. The proposed IGA technique was tested on the IEEE reliability test system (IEEE-RTS), and revealed that the total loss has been significantly reduced. Comparative studies on the results obtained from the IGA with respect to the traditional GA, indicating that IGA outperformed the traditional GA in terms of accuracy and number of iteration. Consecutive efforts can be made to further explore the flexibility and capability of the developed IGA to be implemented in solving other optimisation problems in power system.","PeriodicalId":375856,"journal":{"name":"PECon 2004. Proceedings. National Power and Energy Conference, 2004.","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2004-11-29","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114234809","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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