Pub Date : 2006-10-01DOI: 10.1109/CEIDP.2006.311988
M. Abou-Dakka, A. Bulinski, S. Bamji
DC field long-term breakdown characteristics of commercially available cable-grade cross-linked polyethylene (XLPE) and tree retardant XLPE (TR-XLPE) were investigated. At room temperature, under a unipolar field of 50 kV/mm, more than 90% of XLPE specimens survived 52, 000 h (~6 yrs) of aging, whereas all TR-XLPE specimens broke down within less than 1, 200 h. Reversing the polarity increased the life-time of TR-XLPE by more than 20 times but reduced significantly the life-time of the XLPE specimens. At 75 degC and with polarity reversals both materials survived almost 21, 000 h without any breakdown. These results are discussed in terms of the space charge accumulation and retention properties of the two materials with emphasis on the role of additives in determining insulation properties under DC fields.
{"title":"Space Charge Evolution in XLPE with Long-term Aging under DC Voltage - the Effect of Temperature and Polarity Reversals","authors":"M. Abou-Dakka, A. Bulinski, S. Bamji","doi":"10.1109/CEIDP.2006.311988","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.311988","url":null,"abstract":"DC field long-term breakdown characteristics of commercially available cable-grade cross-linked polyethylene (XLPE) and tree retardant XLPE (TR-XLPE) were investigated. At room temperature, under a unipolar field of 50 kV/mm, more than 90% of XLPE specimens survived 52, 000 h (~6 yrs) of aging, whereas all TR-XLPE specimens broke down within less than 1, 200 h. Reversing the polarity increased the life-time of TR-XLPE by more than 20 times but reduced significantly the life-time of the XLPE specimens. At 75 degC and with polarity reversals both materials survived almost 21, 000 h without any breakdown. These results are discussed in terms of the space charge accumulation and retention properties of the two materials with emphasis on the role of additives in determining insulation properties under DC fields.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"80 4 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116257903","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.311968
W. Sima, Kun Wu, Qing Yang, Caixin Sun
This paper presents a 3D electric-field calculation model of the plusmn800 kV DC transmission line composite insulators based on finite element method. With this 3D model, this paper introduces the effect of the tower, transmission lines and the parameters of the corona rings on the potential and e-field distribution along the composite insulators, and optimizes the corona ring design in order to control the maximum e-field along the insulator surface and corona ring surface.
{"title":"Corona Ring Design of ±800kV DC Composite Insulator Based on Computer Analysis","authors":"W. Sima, Kun Wu, Qing Yang, Caixin Sun","doi":"10.1109/CEIDP.2006.311968","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.311968","url":null,"abstract":"This paper presents a 3D electric-field calculation model of the plusmn800 kV DC transmission line composite insulators based on finite element method. With this 3D model, this paper introduces the effect of the tower, transmission lines and the parameters of the corona rings on the potential and e-field distribution along the composite insulators, and optimizes the corona ring design in order to control the maximum e-field along the insulator surface and corona ring surface.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127882579","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.312083
D. Mary, D. Malec
The electroluminescence activity of different polymers (LDPE, PI, PET, PP and PEN) has been investigated from low to high AC 50 Hz electric fields. Experiments have been focused on the evolution of the electroluminescence intensity versus applied voltage. Three different electroluminescence regimes have been distinguished for both studied polymers.
{"title":"Change in Electroluminescence Activity in Polymers Prior to AC Dielectric Breakdown","authors":"D. Mary, D. Malec","doi":"10.1109/CEIDP.2006.312083","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.312083","url":null,"abstract":"The electroluminescence activity of different polymers (LDPE, PI, PET, PP and PEN) has been investigated from low to high AC 50 Hz electric fields. Experiments have been focused on the evolution of the electroluminescence intensity versus applied voltage. Three different electroluminescence regimes have been distinguished for both studied polymers.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"66 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128042660","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.311982
L. L. Barré, Alun Vaughan, Simon Sutton
This paper examines the solid state ageing characteristics of a technological water-blocking system, based upon the polysaccharide guar, a material used in lightweight power cable designs as a water tree inhibiting system. Through a combination of viscometry and Raman spectroscopy, we show that ageing primarily affects the polymer backbone, which is not associated with guar/water interactions. We conclude that guar binds strongly with water and that this is not affected significantly by ageing. Guar therefore constitutes an attractive means of protecting high voltage insulation systems from exposure to water, so reducing the likelihood of water treeing, even following many years of ageing.
{"title":"Towards water-resistant high voltage insulation systems: An ageing study of a technological water-blocking polymer","authors":"L. L. Barré, Alun Vaughan, Simon Sutton","doi":"10.1109/CEIDP.2006.311982","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.311982","url":null,"abstract":"This paper examines the solid state ageing characteristics of a technological water-blocking system, based upon the polysaccharide guar, a material used in lightweight power cable designs as a water tree inhibiting system. Through a combination of viscometry and Raman spectroscopy, we show that ageing primarily affects the polymer backbone, which is not associated with guar/water interactions. We conclude that guar binds strongly with water and that this is not affected significantly by ageing. Guar therefore constitutes an attractive means of protecting high voltage insulation systems from exposure to water, so reducing the likelihood of water treeing, even following many years of ageing.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122000217","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.311976
S. Sudalaimuthu, M. Thomas, S. Senthil Kumar, V. Vinod Kumar
In the present work an attempt has been made to study the effects of ionizing radiation such as X-ray irradiation on the electrical properties of solid insulating materials such as FR4 laminates and relate these to concurrent changes in the physical and chemical properties of the above material. FR4 laminates find extensive use as an insulating material in PCB's where HV power supply components are mounted in X-ray generators. In the present work samples of FR4 laminates were irradiated in ambient air with X-rays to different absorbed doses of up to 6.3 times 104 rad. The post irradiation effects on the material shows deterioration in electrical properties such as dielectric strength, dissipation factor, volume resistivity and surface resistivity. Analysis by FTIR indicates that when samples are irradiated in air, it exhibits increase of hydroxyl groups and decrease of all the characteristic infrared bands of the initial chemical functions. SEM photographs show newer defects generated in the irradiated sample. There is also a change in color of the material when exposed to X-rays and this is due to the fact that X-ray initiated free charge gets trapped by the defects/impurities and changes the absorption characteristic of the material. In addition, the decrease in crystallinity and increase in surface roughness was monitored by Differential Scanning Calorimetry and contact type profilometer.
{"title":"Effects of X-Ray Radiation on Solid Insulating Materials","authors":"S. Sudalaimuthu, M. Thomas, S. Senthil Kumar, V. Vinod Kumar","doi":"10.1109/CEIDP.2006.311976","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.311976","url":null,"abstract":"In the present work an attempt has been made to study the effects of ionizing radiation such as X-ray irradiation on the electrical properties of solid insulating materials such as FR4 laminates and relate these to concurrent changes in the physical and chemical properties of the above material. FR4 laminates find extensive use as an insulating material in PCB's where HV power supply components are mounted in X-ray generators. In the present work samples of FR4 laminates were irradiated in ambient air with X-rays to different absorbed doses of up to 6.3 times 104 rad. The post irradiation effects on the material shows deterioration in electrical properties such as dielectric strength, dissipation factor, volume resistivity and surface resistivity. Analysis by FTIR indicates that when samples are irradiated in air, it exhibits increase of hydroxyl groups and decrease of all the characteristic infrared bands of the initial chemical functions. SEM photographs show newer defects generated in the irradiated sample. There is also a change in color of the material when exposed to X-rays and this is due to the fact that X-ray initiated free charge gets trapped by the defects/impurities and changes the absorption characteristic of the material. In addition, the decrease in crystallinity and increase in surface roughness was monitored by Differential Scanning Calorimetry and contact type profilometer.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"23 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131384094","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.312104
M. Marzinotto, C. Mazzetti, M. Pompili, P. Schiaffino
Standard lightning impulsive dielectric strength tests were performed on cable model samples manufactured with the same technology and the same materials used for high voltage cable application. In particular four different commercial XLPE compounds are considered. Tests were carried out with the aim to investigate the impulsive strength behaviour at room and 90 degC of the compounds when they are subjected to both positive and negative testing wave polarities. The results have been compared in terms of Weibull scale and shape parameters.
{"title":"Impulsive strength of power cables with different XLPE compounds","authors":"M. Marzinotto, C. Mazzetti, M. Pompili, P. Schiaffino","doi":"10.1109/CEIDP.2006.312104","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.312104","url":null,"abstract":"Standard lightning impulsive dielectric strength tests were performed on cable model samples manufactured with the same technology and the same materials used for high voltage cable application. In particular four different commercial XLPE compounds are considered. Tests were carried out with the aim to investigate the impulsive strength behaviour at room and 90 degC of the compounds when they are subjected to both positive and negative testing wave polarities. The results have been compared in terms of Weibull scale and shape parameters.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"76 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134187837","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.312090
T. Shirotsuka, R. Ohyama
A new type ozone generator with local dielectric barrier discharges operated in very thin gas jets has been experimentally investigated for evaluating an efficient generation process of the ozonic atmosphere. The use of gas jets is to improve an enhancement of the barrier discharges and a cooling effect on the efficiency. The experiments have been conducted to characterize the ozone generation process under following variable parameters: inputted discharge power from a high-voltage source, flow rate of the injected gas jets, and discharge electrode arrangements for optimizing the efficiency. In this paper, a fundamental design of the ozone generator and some quantitative results are presented. The experimentally obtained evaluation indicates an effective performance for the efficiency in a lower range of discharge power.
{"title":"An Experimental Evaluation on Ozone Generation by Local Discharge Type Gas Jets","authors":"T. Shirotsuka, R. Ohyama","doi":"10.1109/CEIDP.2006.312090","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.312090","url":null,"abstract":"A new type ozone generator with local dielectric barrier discharges operated in very thin gas jets has been experimentally investigated for evaluating an efficient generation process of the ozonic atmosphere. The use of gas jets is to improve an enhancement of the barrier discharges and a cooling effect on the efficiency. The experiments have been conducted to characterize the ozone generation process under following variable parameters: inputted discharge power from a high-voltage source, flow rate of the injected gas jets, and discharge electrode arrangements for optimizing the efficiency. In this paper, a fundamental design of the ozone generator and some quantitative results are presented. The experimentally obtained evaluation indicates an effective performance for the efficiency in a lower range of discharge power.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126585184","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.312010
V. Chatpattananan
This document is addressing a problem in classifying partial discharge types using linear discriminant analysis. Four PD types generated in the lab are corona at high voltage side in air, corona at low voltage side in air, surface in air, and internal discharge. The independent variables used in this linear discriminant analysis model mainly are from skewness, kurtosis, asymmetry, and cross correlation following the Phi - q - n PD patterns obtained from the fingerprint analysis which is a digital signal processing technique for PD measurement. This document also applied step wise model selection technique to reduce from 10 independent variables to 8 independent variables that not only reduces the complexity of the model estimated but also retains the accuracy of this predictive model to 98.7 percent.
本文讨论了用线性判别分析对局部放电类型进行分类的问题。实验室产生的四种放电类型分别是空气高压侧电晕、空气低压侧电晕、空气表面电晕和内部放电。该线性判别分析模型中使用的自变量主要来自指纹分析得到的Phi - q - n PD模式的偏度、峰度、不对称性和相互关系，这是一种用于PD测量的数字信号处理技术。本文还应用了分步模型选择技术，将10个自变量减少到8个自变量，不仅降低了模型估计的复杂性，而且使预测模型的准确率保持在98.7%。
{"title":"Linear Discriminant Analysis for Partial Discharge Classification on High Voltage Equipment","authors":"V. Chatpattananan","doi":"10.1109/CEIDP.2006.312010","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.312010","url":null,"abstract":"This document is addressing a problem in classifying partial discharge types using linear discriminant analysis. Four PD types generated in the lab are corona at high voltage side in air, corona at low voltage side in air, surface in air, and internal discharge. The independent variables used in this linear discriminant analysis model mainly are from skewness, kurtosis, asymmetry, and cross correlation following the Phi - q - n PD patterns obtained from the fingerprint analysis which is a digital signal processing technique for PD measurement. This document also applied step wise model selection technique to reduce from 10 independent variables to 8 independent variables that not only reduces the complexity of the model estimated but also retains the accuracy of this predictive model to 98.7 percent.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125208778","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.312015
B. Florkowska, P. Zydroń
Progress in construction of electrical insulation systems needs new investigations of partial discharges (PD) mechanisms. Working conditions and exploitation stresses, i.e. overvoltages, harmonics and other disturbances have crucial influence on arising of PD in insulation systems. Their influence on partial discharge development is different from normal conditions at nominal sinusoidal voltage. In such a cases interpretation of measurement results (by classical or phase-resolved PD images method) could be more difficult. Paper presents influence of sinusoidal and non-sinusoidal testing voltages (triangular and trapezoidal) on partial discharge distributions, their parameters and changes with increasing of applied voltage. The test object was real insulation system (stator bar thermo-setting insulation system) with many internal PD sources. Presented results of measurements made for sinusoidal, triangular and trapezoidal voltages show the PD mechanism in these conditions. Slew-rate of applied voltage with fixed peak voltage value determines specific conditions for PD generation and has important consequences for phase location of discharges.
{"title":"Analysis of conditions of partial discharges inception and development at non-sinusoidal testing voltages","authors":"B. Florkowska, P. Zydroń","doi":"10.1109/CEIDP.2006.312015","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.312015","url":null,"abstract":"Progress in construction of electrical insulation systems needs new investigations of partial discharges (PD) mechanisms. Working conditions and exploitation stresses, i.e. overvoltages, harmonics and other disturbances have crucial influence on arising of PD in insulation systems. Their influence on partial discharge development is different from normal conditions at nominal sinusoidal voltage. In such a cases interpretation of measurement results (by classical or phase-resolved PD images method) could be more difficult. Paper presents influence of sinusoidal and non-sinusoidal testing voltages (triangular and trapezoidal) on partial discharge distributions, their parameters and changes with increasing of applied voltage. The test object was real insulation system (stator bar thermo-setting insulation system) with many internal PD sources. Presented results of measurements made for sinusoidal, triangular and trapezoidal voltages show the PD mechanism in these conditions. Slew-rate of applied voltage with fixed peak voltage value determines specific conditions for PD generation and has important consequences for phase location of discharges.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131021276","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 : 2006-10-01DOI: 10.1109/CEIDP.2006.312087
M. Ashjaee, S. R. Mahmoudi
In the microgravity condition, circulation of liquids with low level of power consumption is extremely attractive. Electrohydrodynamic pumps generate significant pressure heads with low level of power consumption, simple design, low vibration, and acoustic noise. Moreover, the appropriate electrohydrodynamic pressure heads can be achieved easily with variation of applied voltage. Among the electrohydrodynamic pumping methods, the EHD-conduction pumping has a special feature. Owing to the absence of the ion injection effects, the physical and electrical properties of the working fluid remain constant. Pumping through conduction phenomenon is experimentally investigated. An EHD-pump in a horizontal axisymmetric configuration is tested. The working fluids are selected based on their viscosity difference. These two working fluid, Shell Diala AX and 10-GBN Nynas, have the same conductivity approximately. The generated head in the absence of the gravity is obtained. Velocities up to the 0.4 m/s with 0.9 w can be achieved. In the microgravity condition, the viscous forces are balanced just with Electric forces generated by EHD-Pumps. The EHD-conduction pumps promise good chance to use as a circulation pump in cooling or lubricating systems in microgravity condition with low power consumption and without degradation of working fluid.
{"title":"Experimental Study of Electrohydrodynamic Pumping Feasibility In Microgravity Condition through Conduction Phenomenon","authors":"M. Ashjaee, S. R. Mahmoudi","doi":"10.1109/CEIDP.2006.312087","DOIUrl":"https://doi.org/10.1109/CEIDP.2006.312087","url":null,"abstract":"In the microgravity condition, circulation of liquids with low level of power consumption is extremely attractive. Electrohydrodynamic pumps generate significant pressure heads with low level of power consumption, simple design, low vibration, and acoustic noise. Moreover, the appropriate electrohydrodynamic pressure heads can be achieved easily with variation of applied voltage. Among the electrohydrodynamic pumping methods, the EHD-conduction pumping has a special feature. Owing to the absence of the ion injection effects, the physical and electrical properties of the working fluid remain constant. Pumping through conduction phenomenon is experimentally investigated. An EHD-pump in a horizontal axisymmetric configuration is tested. The working fluids are selected based on their viscosity difference. These two working fluid, Shell Diala AX and 10-GBN Nynas, have the same conductivity approximately. The generated head in the absence of the gravity is obtained. Velocities up to the 0.4 m/s with 0.9 w can be achieved. In the microgravity condition, the viscous forces are balanced just with Electric forces generated by EHD-Pumps. The EHD-conduction pumps promise good chance to use as a circulation pump in cooling or lubricating systems in microgravity condition with low power consumption and without degradation of working fluid.","PeriodicalId":219099,"journal":{"name":"2006 IEEE Conference on Electrical Insulation and Dielectric Phenomena","volume":"60 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-10-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114668909","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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