Pub Date : 2007-10-01DOI: 10.1109/EPC.2007.4520391
M. Ivanco, B. Karney, K. J. Waher
A critical analysis on the impacts of a ban on incandescent light bulbs is presented for different regions in Canada. The paper begins with a short history and description of incandescent light bulbs (ILBs) and compact fluorescent light bulbs (CFLBs). The notion that different regions that ban ILBs could increase greenhouse gas (GHG) emissions is introduced. A framework for a comparison of GHG emissions for the ILB and CFLB alternatives is presented. Total GHG emissions for both alternatives are calculated and compared for three provinces in Canada: Quebec, Ontario and Alberta. Finally, there is a discussion on the impacts of the results for each of these locations.
{"title":"To Switch, or Not to Switch: A Critical Analysis of Canada's Ban on Incandescent Light Bulbs","authors":"M. Ivanco, B. Karney, K. J. Waher","doi":"10.1109/EPC.2007.4520391","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520391","url":null,"abstract":"A critical analysis on the impacts of a ban on incandescent light bulbs is presented for different regions in Canada. The paper begins with a short history and description of incandescent light bulbs (ILBs) and compact fluorescent light bulbs (CFLBs). The notion that different regions that ban ILBs could increase greenhouse gas (GHG) emissions is introduced. A framework for a comparison of GHG emissions for the ILB and CFLB alternatives is presented. Total GHG emissions for both alternatives are calculated and compared for three provinces in Canada: Quebec, Ontario and Alberta. Finally, there is a discussion on the impacts of the results for each of these locations.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"28 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129209620","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520388
B. Singh, G. Kasal, A. Chandra, Kamal-Al-Haddad
This paper deals with the regulation of voltage and frequency of an isolated wind energy conversion system (IWECS) based on a capacitor excited asynchronous generator and feeding 3-phase 4-wire loads. The proposed controller consists of an IGBT (Insulted Gate Bipolar Junction Transistor) based 4-leg voltage source converter (VSC) and a battery at its DC link. A bank of excitation capacitor with neutral and fourth leg of the proposed controller provides the neutral terminal for the loads. The complete electromechanical system is modeled and simulated in MATLAB using Simulink and PSB (Power System Blockset) toolboxes. The simulated results are presented to demonstrate the capability of the proposed controller as a voltage and frequency regulator, a harmonic eliminator, a load balancer, and a neutral current compensator for different electrical (consumer loads variation) and mechanical (wind speed variation) dynamic conditions in an isolated wind energy conversion system.
本文研究了一种基于电容励磁异步发电机和馈入三相四线制负载的隔离式风能转换系统的电压和频率调节问题。所提出的控制器由一个基于4腿电压源转换器(VSC)的IGBT(侮辱栅双极结晶体管)和直流链路上的电池组成。一组具有中性点和第四支腿的励磁电容器为负载提供中性点端子。利用Simulink和PSB (Power system Blockset)工具箱在MATLAB中对整个机电系统进行了建模和仿真。仿真结果证明了所提出的控制器作为电压和频率调节器、谐波消除器、负载平衡器和中性电流补偿器的能力，可用于隔离风能转换系统中不同的电气(用户负载变化)和机械(风速变化)动态条件。
{"title":"Improved Power Quality Based Controller for a 3-Phase 4-Wire Isolated Wind Energy System","authors":"B. Singh, G. Kasal, A. Chandra, Kamal-Al-Haddad","doi":"10.1109/EPC.2007.4520388","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520388","url":null,"abstract":"This paper deals with the regulation of voltage and frequency of an isolated wind energy conversion system (IWECS) based on a capacitor excited asynchronous generator and feeding 3-phase 4-wire loads. The proposed controller consists of an IGBT (Insulted Gate Bipolar Junction Transistor) based 4-leg voltage source converter (VSC) and a battery at its DC link. A bank of excitation capacitor with neutral and fourth leg of the proposed controller provides the neutral terminal for the loads. The complete electromechanical system is modeled and simulated in MATLAB using Simulink and PSB (Power System Blockset) toolboxes. The simulated results are presented to demonstrate the capability of the proposed controller as a voltage and frequency regulator, a harmonic eliminator, a load balancer, and a neutral current compensator for different electrical (consumer loads variation) and mechanical (wind speed variation) dynamic conditions in an isolated wind energy conversion system.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"44 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127612692","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520345
W. Santana, K. Al-haddad, S. Rahmani, F. Fnaiech, L. D. da Silva
This work presents a control algorithm for an active resonance damper. This kind of equipment must act as harmonic impedance in order to damp harmonic propagation throughout a distribution feeder. This harmonic resistance must be equal to the characteristic impedance of the distribution feeder in order to achieve optimized compensating currents. As the analytical calculation of this impedance is a non-trivial (and maybe, impossible) task, it is proposed an ARIMAX least-squares based parameters estimator to determine, on line, the optimal value for the harmonic resistance.
{"title":"An Active Resonance Damper for Distribution Systems Using an ARIMAX Parameter Estimator","authors":"W. Santana, K. Al-haddad, S. Rahmani, F. Fnaiech, L. D. da Silva","doi":"10.1109/EPC.2007.4520345","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520345","url":null,"abstract":"This work presents a control algorithm for an active resonance damper. This kind of equipment must act as harmonic impedance in order to damp harmonic propagation throughout a distribution feeder. This harmonic resistance must be equal to the characteristic impedance of the distribution feeder in order to achieve optimized compensating currents. As the analytical calculation of this impedance is a non-trivial (and maybe, impossible) task, it is proposed an ARIMAX least-squares based parameters estimator to determine, on line, the optimal value for the harmonic resistance.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"94 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124445277","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520325
N. Ninad, L. Lopes
Large electrolytic capacitors are usually employed in single-phase grid-connected voltage source inverters (VSI) of distributed energy resources (DER). They are bulky and have a relatively short life time what motivates their replacement by smaller film type capacitors. Resulting issues such as the increased dc bus voltage ripple and smaller inertia to active power variations are discussed in this paper. The former tends to increase the low order harmonics of the injected current, what becomes an even more challenging matter when the bandwidth of the voltage loop is increased to compensate for the latter. A solution based on a voltage ripple estimator is presented and is verified by means of simulation results.
{"title":"Operation of Single-phase Grid-Connected Inverters with Large DC Bus Voltage Ripple","authors":"N. Ninad, L. Lopes","doi":"10.1109/EPC.2007.4520325","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520325","url":null,"abstract":"Large electrolytic capacitors are usually employed in single-phase grid-connected voltage source inverters (VSI) of distributed energy resources (DER). They are bulky and have a relatively short life time what motivates their replacement by smaller film type capacitors. Resulting issues such as the increased dc bus voltage ripple and smaller inertia to active power variations are discussed in this paper. The former tends to increase the low order harmonics of the injected current, what becomes an even more challenging matter when the bandwidth of the voltage loop is increased to compensate for the latter. A solution based on a voltage ripple estimator is presented and is verified by means of simulation results.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128237303","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520360
S. Ashok, P. Balamurugan
Hybrid energy system is an excellent solution for power generation in rural areas where the grid extension is difficult and uneconomical. It is a combination of two or several energy sources such as solar photovoltaic, wind, micro hydro or diesel generators. This offers the advantage that the strengths of each type of sources can be used to complement one another. Hybrid systems can provide electricity at a comparatively economic price. In order to obtain electricity from a hybrid system reliably and at an economically, its design must be optimal in terms of sizing and operation. Biomass gasifier based hybrid energy system has not been reported in literature. The aim of this work is to develop a biomass gasifier based hybrid energy system and to develop optimal operating strategy. An optimization model has also been developed for the optimal operation of the system. The system is modeled using meteorological and load data collected from a typical village. The optimal hybrid system design is realized by satisfying the load demand, non-linear seasonal variations and equipment constraints. The simulations were carried out using HOMER software.
{"title":"Biomass Gasifier Based Hybrid Energy System for Rural Areas","authors":"S. Ashok, P. Balamurugan","doi":"10.1109/EPC.2007.4520360","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520360","url":null,"abstract":"Hybrid energy system is an excellent solution for power generation in rural areas where the grid extension is difficult and uneconomical. It is a combination of two or several energy sources such as solar photovoltaic, wind, micro hydro or diesel generators. This offers the advantage that the strengths of each type of sources can be used to complement one another. Hybrid systems can provide electricity at a comparatively economic price. In order to obtain electricity from a hybrid system reliably and at an economically, its design must be optimal in terms of sizing and operation. Biomass gasifier based hybrid energy system has not been reported in literature. The aim of this work is to develop a biomass gasifier based hybrid energy system and to develop optimal operating strategy. An optimization model has also been developed for the optimal operation of the system. The system is modeled using meteorological and load data collected from a typical village. The optimal hybrid system design is realized by satisfying the load demand, non-linear seasonal variations and equipment constraints. The simulations were carried out using HOMER software.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122269811","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520349
Mu-kuen Chen
This paper investigates the problem of integrated operation in the small wind and photovoltaic(PV) energy power generating system. Theoretically, due to the source impedances of the wind generator and solar cell, it is difficult to charge a battery using both wind and solar energy at the same time. In order to optimize both energy sources, a microprocessor-based controller is used to control the charging system. In addition to acquire both energy sources to improve the reliability of the power system by using a microprocessor-based controller, fluctuations in the small wind power generating system may also be reduced. A 250W permanent magnet generator (PMG) and 75W solar cell panel are used to validate the feasibility of this integrated operating system.
{"title":"The Integrated Operation of a Renewable Power System","authors":"Mu-kuen Chen","doi":"10.1109/EPC.2007.4520349","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520349","url":null,"abstract":"This paper investigates the problem of integrated operation in the small wind and photovoltaic(PV) energy power generating system. Theoretically, due to the source impedances of the wind generator and solar cell, it is difficult to charge a battery using both wind and solar energy at the same time. In order to optimize both energy sources, a microprocessor-based controller is used to control the charging system. In addition to acquire both energy sources to improve the reliability of the power system by using a microprocessor-based controller, fluctuations in the small wind power generating system may also be reduced. A 250W permanent magnet generator (PMG) and 75W solar cell panel are used to validate the feasibility of this integrated operating system.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128403130","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520374
Yu-Jen Lin, Cheng-Yi Hung, T. Hung
This paper investigates the voltage rise due to the regenerative braking of the dc machines associated with the gantry crane. Manipulation of a crane for precisely positioning the container has to operate so fast in order to keep cargo ship punctuality. The major components in a crane of a harbour container centre are the hoist and trolley which are energised by dc motors in this paper. When the dc machines are operating in the regenerative braking mode, it will act as generators and feed a little active power back to the electric system. Such an operating mode sometimes causes unwanted terminal voltage rising up. Extensive computer simulations are executed to illustrate and analysis the phenomena. Some results are obtained at the end of this paper to get rid of the unwanted voltage rise.
{"title":"Voltage Rise due to Regenerative Braking of DC machines associated with Gantry Cranes at Kaohsiung Harbour","authors":"Yu-Jen Lin, Cheng-Yi Hung, T. Hung","doi":"10.1109/EPC.2007.4520374","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520374","url":null,"abstract":"This paper investigates the voltage rise due to the regenerative braking of the dc machines associated with the gantry crane. Manipulation of a crane for precisely positioning the container has to operate so fast in order to keep cargo ship punctuality. The major components in a crane of a harbour container centre are the hoist and trolley which are energised by dc motors in this paper. When the dc machines are operating in the regenerative braking mode, it will act as generators and feed a little active power back to the electric system. Such an operating mode sometimes causes unwanted terminal voltage rising up. Extensive computer simulations are executed to illustrate and analysis the phenomena. Some results are obtained at the end of this paper to get rid of the unwanted voltage rise.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"8 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129915288","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520301
Y. M. Attwa, E. El-Saadany
DGs are gaining more importance and they are expected to drastically change the whole distribution system practices. Distribution network will be no longer a passive termination of transmission network and the concept of active network has been recently introduced to indicate a new kind of distribution with DGs actively involved in system management and operation. One of the most important benefits of DGs is reliability improvement. Therefore, in this paper a new methodology, based on system segmentation concept is proposed in order to select the optimum size and location of DGs required to maximize the system reliability. Moreover, a software was developed with the capability of scanning the distribution system in order to divide it into several operational segments based on the utilized protection devices. The reliability of each individual segment as well as the system reliability was evaluated based on selective reliability indices. Nevertheless, more indices can be taken into consideration for the evaluation process. This concept is applied to a practical distribution system, and the results showed that there is a great relation between size and location of DG and reliability improvement.
{"title":"Reliability Based Analysis for Optimum Allocation of DG","authors":"Y. M. Attwa, E. El-Saadany","doi":"10.1109/EPC.2007.4520301","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520301","url":null,"abstract":"DGs are gaining more importance and they are expected to drastically change the whole distribution system practices. Distribution network will be no longer a passive termination of transmission network and the concept of active network has been recently introduced to indicate a new kind of distribution with DGs actively involved in system management and operation. One of the most important benefits of DGs is reliability improvement. Therefore, in this paper a new methodology, based on system segmentation concept is proposed in order to select the optimum size and location of DGs required to maximize the system reliability. Moreover, a software was developed with the capability of scanning the distribution system in order to divide it into several operational segments based on the utilized protection devices. The reliability of each individual segment as well as the system reliability was evaluated based on selective reliability indices. Nevertheless, more indices can be taken into consideration for the evaluation process. This concept is applied to a practical distribution system, and the results showed that there is a great relation between size and location of DG and reliability improvement.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128878085","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520361
A. Aguiar, J. Pinto, C. Andrea, L. Nogueira
The aim of this work is to present a daily simulation model for technical and economical analysis of natural gas microturbine application for residential complex. From the energy generation side, the model is based on the microturbine electrical and thermal efficiency, and on the boiler, heat exchanger and chiller equations. On the other hand, from the load side, the model is based on consumer electrical and thermal load curves. In this way, simulation for different scenarios can be made, and their results may be used as decision support systems by investors. The main advantage of this model is the timeframe that is used, which is flexible, varying from hours, days, weeks, up to years. Therefore, the work granularity allows take into consideration details that conventional methodology does not. In this paper is given details of the model, and simulation results are provided to show it feasibility.
{"title":"Modeling and Simulation of Natural Gas Microturbine Application for Residential Complex Aiming Technical and Economical Viability Analysis","authors":"A. Aguiar, J. Pinto, C. Andrea, L. Nogueira","doi":"10.1109/EPC.2007.4520361","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520361","url":null,"abstract":"The aim of this work is to present a daily simulation model for technical and economical analysis of natural gas microturbine application for residential complex. From the energy generation side, the model is based on the microturbine electrical and thermal efficiency, and on the boiler, heat exchanger and chiller equations. On the other hand, from the load side, the model is based on consumer electrical and thermal load curves. In this way, simulation for different scenarios can be made, and their results may be used as decision support systems by investors. The main advantage of this model is the timeframe that is used, which is flexible, varying from hours, days, weeks, up to years. Therefore, the work granularity allows take into consideration details that conventional methodology does not. In this paper is given details of the model, and simulation results are provided to show it feasibility.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133958826","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 : 2007-10-01DOI: 10.1109/EPC.2007.4520355
M. Zamani, G. H. Riahy, A. Ardakani
The Power curve of wind turbine ignores the dynamic behavior of the wind and represents the wind turbine power as a function of the average wind speed. Power curve is not an adequate tool for estimating the power of variable speed wind turbines. Because, in addition to average wind speed, the output power of these turbines is highly dependent on the dynamic of the wind. In this paper, by introducing a new curve named controllers power curve, a method is presented to modify power curve of variable speed wind turbines according to the wind dynamics. The controllers' power curve is a 3-D curve that represent the amount of electrical power that generated because of controllers' performance taking to account the wind characteristics and reactions of controllers to instantaneous wind speed variations. In proposed method, the EPF of the wind represents the wind dynamics. Also the controllers' performance is simulated using a new factor named controllability factor. Simulation studies showed the effectiveness of the proposed method based on controllers' power curve.
{"title":"Modifying power curve of Variable Speed Wind Turbines by Performance Evaluation of Pitch-Angle and Rotor Speed Controllers","authors":"M. Zamani, G. H. Riahy, A. Ardakani","doi":"10.1109/EPC.2007.4520355","DOIUrl":"https://doi.org/10.1109/EPC.2007.4520355","url":null,"abstract":"The Power curve of wind turbine ignores the dynamic behavior of the wind and represents the wind turbine power as a function of the average wind speed. Power curve is not an adequate tool for estimating the power of variable speed wind turbines. Because, in addition to average wind speed, the output power of these turbines is highly dependent on the dynamic of the wind. In this paper, by introducing a new curve named controllers power curve, a method is presented to modify power curve of variable speed wind turbines according to the wind dynamics. The controllers' power curve is a 3-D curve that represent the amount of electrical power that generated because of controllers' performance taking to account the wind characteristics and reactions of controllers to instantaneous wind speed variations. In proposed method, the EPF of the wind represents the wind dynamics. Also the controllers' performance is simulated using a new factor named controllability factor. Simulation studies showed the effectiveness of the proposed method based on controllers' power curve.","PeriodicalId":196861,"journal":{"name":"2007 IEEE Canada Electrical Power Conference","volume":"68 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134628671","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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