Pub Date : 2007-11-01DOI: 10.1109/ISAP.2007.4441692
Young-Soo Park, Jin-ho Kim, Juneho Park, Junying Hong
This paper addresses a hybrid particle swarm optimization-based approach for solving a generating unit maintenance scheduling problem (GMS). We focus on the power system reliability such as reserve ratio better than cost function as the objective function of GMS problem. It is shown that particle swarm optimization-based method is more effective in obtaining feasible schedules such as GMS problem related to power system planning and operation. In our paper, we find the optimal solution of the GMS problem within a specific time horizon using hybrid PSO algorithm, simple modification to the standard particle swarm optimization adding mutation operator of GA to solve the stagnation problem. Actual data obtained from the IEEE reliability test system (1996) including 32-generators are applicable to the GMS problem. From the result, we can conclude that the hybrid PSO is enough to look for the optimal solution effectively in the generating unit maintenance scheduling problem. It is also envisaged that hybrid PSO (HPSO) algorithm can be easily implemented for similar optimizations and scheduling problems in power system problems to obtain improved solutions.
{"title":"Generating Unit Maintenance Scheduling using Hybrid PSO Algorithm","authors":"Young-Soo Park, Jin-ho Kim, Juneho Park, Junying Hong","doi":"10.1109/ISAP.2007.4441692","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441692","url":null,"abstract":"This paper addresses a hybrid particle swarm optimization-based approach for solving a generating unit maintenance scheduling problem (GMS). We focus on the power system reliability such as reserve ratio better than cost function as the objective function of GMS problem. It is shown that particle swarm optimization-based method is more effective in obtaining feasible schedules such as GMS problem related to power system planning and operation. In our paper, we find the optimal solution of the GMS problem within a specific time horizon using hybrid PSO algorithm, simple modification to the standard particle swarm optimization adding mutation operator of GA to solve the stagnation problem. Actual data obtained from the IEEE reliability test system (1996) including 32-generators are applicable to the GMS problem. From the result, we can conclude that the hybrid PSO is enough to look for the optimal solution effectively in the generating unit maintenance scheduling problem. It is also envisaged that hybrid PSO (HPSO) algorithm can be easily implemented for similar optimizations and scheduling problems in power system problems to obtain improved solutions.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127404340","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441607
M. Joung, Jinho Kim, K.Y. Lee
This paper investigates the ways in which an electricity capacity market design may encourage generators to exaggerate their available capacity. For concrete analysis, a simple two-player game model is introduced, focusing on two pure strategy Nash equilibria: an equilibrium at which generators offer their true capacities, and an equilibrium at which generators offer exaggerated capacities. The latter case is caused by asymmetries of information between players and called 'moral hazard' in the economics literature. Our consideration of the practical electricity markets reveals that the moral hazard case is highly probable. Moreover, consideration of the current capacity market design in the real world led us to conclude that the better the electricity energy market performs, the higher the risk of moral hazard becomes. For illustration, a numerical example is presented.
{"title":"Moral Hazard in the Electricity Capacity Markets","authors":"M. Joung, Jinho Kim, K.Y. Lee","doi":"10.1109/ISAP.2007.4441607","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441607","url":null,"abstract":"This paper investigates the ways in which an electricity capacity market design may encourage generators to exaggerate their available capacity. For concrete analysis, a simple two-player game model is introduced, focusing on two pure strategy Nash equilibria: an equilibrium at which generators offer their true capacities, and an equilibrium at which generators offer exaggerated capacities. The latter case is caused by asymmetries of information between players and called 'moral hazard' in the economics literature. Our consideration of the practical electricity markets reveals that the moral hazard case is highly probable. Moreover, consideration of the current capacity market design in the real world led us to conclude that the better the electricity energy market performs, the higher the risk of moral hazard becomes. For illustration, a numerical example is presented.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"30 1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132553607","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441622
Li Wang, T. Lin
This paper presents small-signal stability, steady-state characteristics, and dynamic performance of an autonomous hybrid wind-PV-battery system feeding an isolated single-phase load. To improve the inherent variable frequency, variable voltage, and loading effects of the studied wind synchronous generator (SG) under random wind speeds, an AC-to-DC converter and a battery system are employed to combine distinct generated energies from the wind SG and a PV module. The stored energy in the battery is converted into a single-phase source with constant voltage and constant frequency to supply isolated single-phase loads by means of a DC-to-DC boost converter and a DC-to-AC inverter. The d-q axis equivalent-circuit models for the SG, AC-to-DC converter, DC-to-AC inverter, DC-to-DC boost converter, PV module, and battery system are respectively derived to establish the complete dynamic system equations of the studied hybrid system. Experimental results obtained from a laboratory 300 W SG, a 24 V, 1.5 kW PV module, and a 24 V, 250 Ah battery system are compared with the simulated results to validate the proposed system model. Small-signal stability of the studied system under various operating points and different disturbance conditions is also carried out by using eigenvalue analysis and dynamic simulations, respectively.
{"title":"Stability and Performance of an Autonomous Hybrid Wind-PV-Battery System","authors":"Li Wang, T. Lin","doi":"10.1109/ISAP.2007.4441622","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441622","url":null,"abstract":"This paper presents small-signal stability, steady-state characteristics, and dynamic performance of an autonomous hybrid wind-PV-battery system feeding an isolated single-phase load. To improve the inherent variable frequency, variable voltage, and loading effects of the studied wind synchronous generator (SG) under random wind speeds, an AC-to-DC converter and a battery system are employed to combine distinct generated energies from the wind SG and a PV module. The stored energy in the battery is converted into a single-phase source with constant voltage and constant frequency to supply isolated single-phase loads by means of a DC-to-DC boost converter and a DC-to-AC inverter. The d-q axis equivalent-circuit models for the SG, AC-to-DC converter, DC-to-AC inverter, DC-to-DC boost converter, PV module, and battery system are respectively derived to establish the complete dynamic system equations of the studied hybrid system. Experimental results obtained from a laboratory 300 W SG, a 24 V, 1.5 kW PV module, and a 24 V, 250 Ah battery system are compared with the simulated results to validate the proposed system model. Small-signal stability of the studied system under various operating points and different disturbance conditions is also carried out by using eigenvalue analysis and dynamic simulations, respectively.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131573131","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441625
B. Suthar, R. Balasubramanian
This paper presents an ANN based method for online voltage stability assessment of power systems. The most vulnerable load buses of the system from voltage stability point of view have been identified by Modal analysis. A separate feed forward type of ANN is trained for each vulnerable load bus. For each of these ANN's, some novel inputs, comprising of the moments obtained by multiplying the real power and reactive power contributions with the electrical distance between each generator-vulnerable load bus pair and the reactive power margins available at the generators, are used in addition to the usually used inputs viz. the real and reactive power loads and the voltage magnitude at the vulnerable load bus. The target output for each input pattern is obtained by computing the distance to voltage collapse from the current system operating point using a continuation power flow type algorithm (Contour Program) incorporating the Q limits of the generators. The proposed method has been applied to the IEEE 30 bus test system. The distances to voltage collapse obtained by the ANN and by the analytical method are found to be closely matching with each other.
{"title":"A Novel ANN Based Method for Online Voltage Stability Assessment","authors":"B. Suthar, R. Balasubramanian","doi":"10.1109/ISAP.2007.4441625","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441625","url":null,"abstract":"This paper presents an ANN based method for online voltage stability assessment of power systems. The most vulnerable load buses of the system from voltage stability point of view have been identified by Modal analysis. A separate feed forward type of ANN is trained for each vulnerable load bus. For each of these ANN's, some novel inputs, comprising of the moments obtained by multiplying the real power and reactive power contributions with the electrical distance between each generator-vulnerable load bus pair and the reactive power margins available at the generators, are used in addition to the usually used inputs viz. the real and reactive power loads and the voltage magnitude at the vulnerable load bus. The target output for each input pattern is obtained by computing the distance to voltage collapse from the current system operating point using a continuation power flow type algorithm (Contour Program) incorporating the Q limits of the generators. The proposed method has been applied to the IEEE 30 bus test system. The distances to voltage collapse obtained by the ANN and by the analytical method are found to be closely matching with each other.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"8 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125679483","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441673
J. Matics, G. Krost
Micro combined heat and power (CHP) systems for single or small ensembles of (residential) buildings are seen advantageous to combine both decentralized power supply and rather high overall efficiency. The latter presupposes flexible and adaptive plant management which has to mediate between energy cost minimization and user comfort aspects. The successful use of computational intelligence (CI) techniques for this purpose is focused and shown with several examples.
{"title":"Computational Intelligence Techniques Applied to Flexible and Auto-adaptive Operation of CHP Based Home Power Supply","authors":"J. Matics, G. Krost","doi":"10.1109/ISAP.2007.4441673","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441673","url":null,"abstract":"Micro combined heat and power (CHP) systems for single or small ensembles of (residential) buildings are seen advantageous to combine both decentralized power supply and rather high overall efficiency. The latter presupposes flexible and adaptive plant management which has to mediate between energy cost minimization and user comfort aspects. The successful use of computational intelligence (CI) techniques for this purpose is focused and shown with several examples.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"73 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126461635","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441595
V. S. Pappala, S.N. Singh, M. Wilch, I. Erlich
According to the new grid codes, wind parks must operate similar to other conventional power plants. Offshore wind parks are connected to the main grid with long cables and reactive power management is a big concern to the operators in the changing wind power conditions. This paper addresses the optimal reactive power dispatch (ORPD), which is a mixed-integer nonlinear optimization problem. The integer variables in ORPD are tap positions of the transformers, switching of cables and switched reactors, if present. A new adaptive particle swarm optimization (APSO), which is free from tuning of population size and is based on different sized groups of particles called "Tribes", is used to solve the ORPD problem. The proposed APSO is embedded in the Newton-Raphson load flow program. The effectiveness of the proposed algorithm is demonstrated on a real offshore wind farm, which is currently in planning stage, in Germany.
{"title":"Reactive Power Management in Offshore Wind Farms by Adaptive PSO","authors":"V. S. Pappala, S.N. Singh, M. Wilch, I. Erlich","doi":"10.1109/ISAP.2007.4441595","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441595","url":null,"abstract":"According to the new grid codes, wind parks must operate similar to other conventional power plants. Offshore wind parks are connected to the main grid with long cables and reactive power management is a big concern to the operators in the changing wind power conditions. This paper addresses the optimal reactive power dispatch (ORPD), which is a mixed-integer nonlinear optimization problem. The integer variables in ORPD are tap positions of the transformers, switching of cables and switched reactors, if present. A new adaptive particle swarm optimization (APSO), which is free from tuning of population size and is based on different sized groups of particles called \"Tribes\", is used to solve the ORPD problem. The proposed APSO is embedded in the Newton-Raphson load flow program. The effectiveness of the proposed algorithm is demonstrated on a real offshore wind farm, which is currently in planning stage, in Germany.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114239046","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441599
J. Coser, D.T. do Vale, J. Rolim
Artificial Neural Networks constitute a suitable approach for pointing out a fault location in radial distribution feeders, even when the fault current has a small value, near the normal load of the system. Some publications have described successful application of artificial neural networks to the fault location problem, but there are still some difficulties that may limit their applicability to a real system, mainly the complexity of the problem when lateral derivations are included as possible fault locations. There are some inherent aspects in distribution networks that prevent the straightforward application of transmission network methodologies to distribution systems. This paper describes a new approach to the use of Artificial Neural Networks for the solution of the fault location problem in energy distribution systems. The objective is to obtain accurate results and to optimize the training stage, all using only the fundamental frequency component of the currents monitored at the substation.
{"title":"Design and Training of Artificial Neural Networks for Locating Low Current Faults in Distribution Systems","authors":"J. Coser, D.T. do Vale, J. Rolim","doi":"10.1109/ISAP.2007.4441599","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441599","url":null,"abstract":"Artificial Neural Networks constitute a suitable approach for pointing out a fault location in radial distribution feeders, even when the fault current has a small value, near the normal load of the system. Some publications have described successful application of artificial neural networks to the fault location problem, but there are still some difficulties that may limit their applicability to a real system, mainly the complexity of the problem when lateral derivations are included as possible fault locations. There are some inherent aspects in distribution networks that prevent the straightforward application of transmission network methodologies to distribution systems. This paper describes a new approach to the use of Artificial Neural Networks for the solution of the fault location problem in energy distribution systems. The objective is to obtain accurate results and to optimize the training stage, all using only the fundamental frequency component of the currents monitored at the substation.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"240 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122065340","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441651
Cong-Hui Huang, Whei-Min Lin
This paper presents an enhanced immune annealing algorithm (EIAA) for the solution of the optimal power flow based on Equivalent Current-Injection (ECIOPF) with both continuous and discrete control variables that was called mixed-integer optimal power flow (MIOPF). The continuous control variables modeled are unit active power outputs and generator-bus voltage magnitudes, while the discrete ones are transformer-tap settings and shunt capacitor devices. The feasibility of the proposed method is exhibited for standard IEEE 30 bus system, and it is compared with other stochastic methods in terms of solution quality, convergence property, and computation efficiency.
{"title":"An Enhanced Immune-Annealing Algorithm for Mixed-Integer Optimal Power Flow","authors":"Cong-Hui Huang, Whei-Min Lin","doi":"10.1109/ISAP.2007.4441651","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441651","url":null,"abstract":"This paper presents an enhanced immune annealing algorithm (EIAA) for the solution of the optimal power flow based on Equivalent Current-Injection (ECIOPF) with both continuous and discrete control variables that was called mixed-integer optimal power flow (MIOPF). The continuous control variables modeled are unit active power outputs and generator-bus voltage magnitudes, while the discrete ones are transformer-tap settings and shunt capacitor devices. The feasibility of the proposed method is exhibited for standard IEEE 30 bus system, and it is compared with other stochastic methods in terms of solution quality, convergence property, and computation efficiency.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"16 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114970145","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441670
Y. Pradeep, S. Khaparde, R. Kumar
Indian power sector is growing at an enormous pace. Building and operating such a power system is a challenging problem. The power network which carries the MWs across large distances is analogous to a "muscle system" of human body. Likewise, the entire range of associated monitoring and control network is analogous to a "nervous system". While strengthening the muscles is important in order to fully realize the potential, they also have to be complemented by an intelligent nervous system. This paper focuses on the intelligent grid aspects and the initiatives taken by the National Grid of India towards that direction. The participation of IBM - Indian Institute of Technology, Bombay (IITB) in the intelligent utility network (IUN) research is also mentioned.
{"title":"Intelligent Grid Initiatives in India","authors":"Y. Pradeep, S. Khaparde, R. Kumar","doi":"10.1109/ISAP.2007.4441670","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441670","url":null,"abstract":"Indian power sector is growing at an enormous pace. Building and operating such a power system is a challenging problem. The power network which carries the MWs across large distances is analogous to a \"muscle system\" of human body. Likewise, the entire range of associated monitoring and control network is analogous to a \"nervous system\". While strengthening the muscles is important in order to fully realize the potential, they also have to be complemented by an intelligent nervous system. This paper focuses on the intelligent grid aspects and the initiatives taken by the National Grid of India towards that direction. The participation of IBM - Indian Institute of Technology, Bombay (IITB) in the intelligent utility network (IUN) research is also mentioned.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123043124","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 : 2007-11-01DOI: 10.1109/ISAP.2007.4441648
D. Lucarella, S. Massucco, F. Silvestro, G. Vimercati
In operational practice power system security analyses are usually conducted with respect to "credible" contingencies, such as almost all N-l contingencies and some N-2 contingencies suggested by operational experience. Moreover it is normally conducted in an off-line approach. The paper presents an extensive analysis performed on a realistic network representative of the Italian HV grid by means of a Dynamic Security Assessment (DSA) application tool. The paper is aimed at proposing some improvements for the DSA tool through an integration between the original simulator environment and MATLAB functions, used to automatically generate different scenarios to be processed. The goal of this study is to analyze different scenarios and investigate the possibility to correlate some network parameters (such as reactive margins, voltages, etc.) to the Voltage Stability margin provided by a DSA tool.
{"title":"On - line generation of synthetic information on voltage stability margins","authors":"D. Lucarella, S. Massucco, F. Silvestro, G. Vimercati","doi":"10.1109/ISAP.2007.4441648","DOIUrl":"https://doi.org/10.1109/ISAP.2007.4441648","url":null,"abstract":"In operational practice power system security analyses are usually conducted with respect to \"credible\" contingencies, such as almost all N-l contingencies and some N-2 contingencies suggested by operational experience. Moreover it is normally conducted in an off-line approach. The paper presents an extensive analysis performed on a realistic network representative of the Italian HV grid by means of a Dynamic Security Assessment (DSA) application tool. The paper is aimed at proposing some improvements for the DSA tool through an integration between the original simulator environment and MATLAB functions, used to automatically generate different scenarios to be processed. The goal of this study is to analyze different scenarios and investigate the possibility to correlate some network parameters (such as reactive margins, voltages, etc.) to the Voltage Stability margin provided by a DSA tool.","PeriodicalId":320068,"journal":{"name":"2007 International Conference on Intelligent Systems Applications to Power Systems","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115332514","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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