Pub Date : 2006-12-04DOI: 10.1109/INTLEC.2006.251639
J. Qahouq, L. Huang
A gradient power architecture concept with non-uniform current/power sharing is presented in this paper. A voltage regulator with this concept is designed, analyzed, and experimented. This scheme results in improved efficiency especially at lighter loads and the ability to control steady-state and dynamic performance especially when some of the phases are turned OFF at lighter loads
{"title":"Power Converter with Gradient Power Architecture and Non-Uniform Current Sharing","authors":"J. Qahouq, L. Huang","doi":"10.1109/INTLEC.2006.251639","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251639","url":null,"abstract":"A gradient power architecture concept with non-uniform current/power sharing is presented in this paper. A voltage regulator with this concept is designed, analyzed, and experimented. This scheme results in improved efficiency especially at lighter loads and the ability to control steady-state and dynamic performance especially when some of the phases are turned OFF at lighter loads","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"49 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115924807","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251641
T. Guena, P. Leblanc
Batteries used as energy storage in telecommunications applications do not usually cycle over their full rated capacity. These batteries spend most of the time floating at full charge, and during discharges, only a fraction of the battery capacity is used depending on the time of the power outage. The cycle life of a battery is often reported at 100% depth of discharge (DOD) of the capacity and it usually corresponds to a worst-case scenario. In this paper, the impact of cycling at different DODs on LMP battery cycling performances was investigated. The depth of discharge was correlated to capacity fade and coulombic efficiency. Various cycling protocols covering a range of DODs have been applied to LMP cells at 43 degC and 60 degC. Analysis of the data was made considering both depth of discharge and cumulative discharge capacity throughout the test. We will report on the beneficial effect of decreasing DOD on the cycle life performances of LMP technology, resulting in a significant cycle life improvement
{"title":"How Depth of Discharge Affects the Cycle Life of Lithium-Metal-Polymer Batteries","authors":"T. Guena, P. Leblanc","doi":"10.1109/INTLEC.2006.251641","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251641","url":null,"abstract":"Batteries used as energy storage in telecommunications applications do not usually cycle over their full rated capacity. These batteries spend most of the time floating at full charge, and during discharges, only a fraction of the battery capacity is used depending on the time of the power outage. The cycle life of a battery is often reported at 100% depth of discharge (DOD) of the capacity and it usually corresponds to a worst-case scenario. In this paper, the impact of cycling at different DODs on LMP battery cycling performances was investigated. The depth of discharge was correlated to capacity fade and coulombic efficiency. Various cycling protocols covering a range of DODs have been applied to LMP cells at 43 degC and 60 degC. Analysis of the data was made considering both depth of discharge and cumulative discharge capacity throughout the test. We will report on the beneficial effect of decreasing DOD on the cycle life performances of LMP technology, resulting in a significant cycle life improvement","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129049869","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251660
N. Pongratananukul
Analyzing switched-mode power supply's control characteristics is challenging due to the high nonlinearity, and various new topologies are introduced. The mathematical complexity is a burden and is prone to error and oversimplification. Tradition approach includes finding the DC operating point and applying the small-signal linearization process. In this paper, a test bench method is developed to extract frequency response using "as is" circuit via time domain simulation. Advanced features in SPICE are used to automate over 80% of the process for finding frequency response in transient domain in the proposed simulation platform, similar to how the network analyzer is actually used. Besides constructing the circuit diagram, only some simulation setup is required. Although a long simulation time is needed, we can see several benefits including: 1) the method will work with any circuit topology, 2) it allows theoretical evaluation before any hardware become available, and 3) since the frequency response is found in transient mode, we can incorporate all circuit parameters and avoid simplified modeling assumptions. Fundamental frequency components are extracted out of the converter time-domain responses that are usually simulated in a variable time-step mode. The Fourier series are calculated inside SPICE via continuous-time behavioral models. Simulation platform is applied to study the "input voltage regulation (IVR)" of the maximum power point tracking control when the input voltage regulation is active with modeling of peak-current mode converter. Further an advanced programming language is used to extract data from output data file
{"title":"Spice-based Automated Software Network Analyzer","authors":"N. Pongratananukul","doi":"10.1109/INTLEC.2006.251660","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251660","url":null,"abstract":"Analyzing switched-mode power supply's control characteristics is challenging due to the high nonlinearity, and various new topologies are introduced. The mathematical complexity is a burden and is prone to error and oversimplification. Tradition approach includes finding the DC operating point and applying the small-signal linearization process. In this paper, a test bench method is developed to extract frequency response using \"as is\" circuit via time domain simulation. Advanced features in SPICE are used to automate over 80% of the process for finding frequency response in transient domain in the proposed simulation platform, similar to how the network analyzer is actually used. Besides constructing the circuit diagram, only some simulation setup is required. Although a long simulation time is needed, we can see several benefits including: 1) the method will work with any circuit topology, 2) it allows theoretical evaluation before any hardware become available, and 3) since the frequency response is found in transient mode, we can incorporate all circuit parameters and avoid simplified modeling assumptions. Fundamental frequency components are extracted out of the converter time-domain responses that are usually simulated in a variable time-step mode. The Fourier series are calculated inside SPICE via continuous-time behavioral models. Simulation platform is applied to study the \"input voltage regulation (IVR)\" of the maximum power point tracking control when the input voltage regulation is active with modeling of peak-current mode converter. Further an advanced programming language is used to extract data from output data file","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131960211","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251653
V. Boscaino, G. Di Blasi, P. Livreri, F. Marino, M. Minieri
This paper describes an innovative digital PWM control implementation for low voltage, high current DC-DC converters. The proposed technique, based on the use of a low resolution DAC, improves steady-state performances, minimizing limit cycle effects. The novel technique is tested on a FPGA-based single phase buck converter operating at 250 kHz. A detailed description of the proposed architecture is given and test results, simulation and experimental ones, are shown
{"title":"A novel digital control for DC/DC converters to improve steady-state performances","authors":"V. Boscaino, G. Di Blasi, P. Livreri, F. Marino, M. Minieri","doi":"10.1109/INTLEC.2006.251653","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251653","url":null,"abstract":"This paper describes an innovative digital PWM control implementation for low voltage, high current DC-DC converters. The proposed technique, based on the use of a low resolution DAC, improves steady-state performances, minimizing limit cycle effects. The novel technique is tested on a FPGA-based single phase buck converter operating at 250 kHz. A detailed description of the proposed architecture is given and test results, simulation and experimental ones, are shown","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126255031","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251667
M. Perry, E. Strayer
Fuel cells combine the best features of engine-driven generators and batteries, since they can operate for as long as fuel is available and they produce electricity directly from this fuel via electrochemistry, which is inherently more efficient than combustion and minimizes the adverse characteristics associated with combustion engines (e.g., excessive noise, emissions, and maintenance). Therefore, fuel cells offer a potentially attractive back-up power solution for telecom sites where extended run times are desired, but generators are considered unacceptable. As customer expectations for a variety of uninterrupted communication technologies increase and/or as the reliability of the electric grid decreases, these fuel-cell attributes will become increasing attractive. However, in order to be widely accepted for telecom-power applications, fuel cells must prove that they are more reliable and cost competitive than the incumbent solutions. This will require fuel-cell systems that are very simple, yet also very small, since added complexity and size results in inherently unreliable and expensive products. UTC Power has developed a back-up power product for telecom applications, which utilizes proprietary technology that requires minimal number of balance-of-plant components and has a polymer-electrolyte membrane fuel-cell (PEMFC) stack with unmatched power density. The fundamental PEMFC technology that enables this unique system will be explained, as well as a brief description of a complete 5-kW back-up power product
{"title":"Fuel-Cell Based Back-Up Power for Telecommunication Applications: Developing a Reliable and Cost-Effective Solution","authors":"M. Perry, E. Strayer","doi":"10.1109/INTLEC.2006.251667","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251667","url":null,"abstract":"Fuel cells combine the best features of engine-driven generators and batteries, since they can operate for as long as fuel is available and they produce electricity directly from this fuel via electrochemistry, which is inherently more efficient than combustion and minimizes the adverse characteristics associated with combustion engines (e.g., excessive noise, emissions, and maintenance). Therefore, fuel cells offer a potentially attractive back-up power solution for telecom sites where extended run times are desired, but generators are considered unacceptable. As customer expectations for a variety of uninterrupted communication technologies increase and/or as the reliability of the electric grid decreases, these fuel-cell attributes will become increasing attractive. However, in order to be widely accepted for telecom-power applications, fuel cells must prove that they are more reliable and cost competitive than the incumbent solutions. This will require fuel-cell systems that are very simple, yet also very small, since added complexity and size results in inherently unreliable and expensive products. UTC Power has developed a back-up power product for telecom applications, which utilizes proprietary technology that requires minimal number of balance-of-plant components and has a polymer-electrolyte membrane fuel-cell (PEMFC) stack with unmatched power density. The fundamental PEMFC technology that enables this unique system will be explained, as well as a brief description of a complete 5-kW back-up power product","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125721464","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251598
Y. Kawanami, M. Ueno, Y. Ishizuka, H. Matsuo, K. Ito
A current-compensation circuit system for POLs is introduced. The proposed circuit employs MOSFETs, resistors and capacitors without any discrete magnetic devices. The system is activated only during transient responses and its total power loss is very small. Simulation results revealed that the output POL voltage is maintained within 5 % of 1.5 V during a load change between 1 A and 10 A
{"title":"A Fast Response Current-Compensation Circuit for POL","authors":"Y. Kawanami, M. Ueno, Y. Ishizuka, H. Matsuo, K. Ito","doi":"10.1109/INTLEC.2006.251598","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251598","url":null,"abstract":"A current-compensation circuit system for POLs is introduced. The proposed circuit employs MOSFETs, resistors and capacitors without any discrete magnetic devices. The system is activated only during transient responses and its total power loss is very small. Simulation results revealed that the output POL voltage is maintained within 5 % of 1.5 V during a load change between 1 A and 10 A","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124983291","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251628
M. Orabi, M. el-Zanaty
Buck converters have counted a lot of problems last days as the industry trend moves towards high operating frequency. Moreover, future VRM requires high output current/low voltages that results in tight duty cycles, especially in case of higher input voltages that can not be achieved in the practical circuit. A lot of solutions have been proposed, one of them can be using flyback converter. Therefore, in this paper, a comparison between two converters, buck converter and flyback converters operating as voltage-regulated-module (VRM) is provided. The advantage and disadvantage of every converter is listed and a detailed comparison is introduced
{"title":"Comparison of Different Schemes for VRM Application","authors":"M. Orabi, M. el-Zanaty","doi":"10.1109/INTLEC.2006.251628","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251628","url":null,"abstract":"Buck converters have counted a lot of problems last days as the industry trend moves towards high operating frequency. Moreover, future VRM requires high output current/low voltages that results in tight duty cycles, especially in case of higher input voltages that can not be achieved in the practical circuit. A lot of solutions have been proposed, one of them can be using flyback converter. Therefore, in this paper, a comparison between two converters, buck converter and flyback converters operating as voltage-regulated-module (VRM) is provided. The advantage and disadvantage of every converter is listed and a detailed comparison is introduced","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"36 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127856503","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251645
D. McMenamin
The intent of this paper is to show the need for adequate bracing and framing of cable trays in the central office environment, particularly cable racks bearing power cables. Power busbars and cabling are the densest conductors in the telecommunications environment and everything in the central office is dependant on power. The paper will cover seismic influences on the cabling structures and the ways in which seismic displacement could result in systemic failure of the telecommunications systems if the mechanical support for the cabling or buswork is inadequate. The paper also will cover bracing and framing for busbars and busduct systems with text and illustrations. The paper will cover bracing and framing for cable trays including primary and secondary power cables, communication cables and optical fiber cable trays. Most telecommunications huts and CEVs are equipped with adequate cableways and so this paper is intended to speak mainly to central office cabling whether for wireline or wireless use and for data centers with DC powered systems. Finally, the paper will socialize an idea in the telecom community. Unfortunately, the way the National Fire Protection Association (NFPA) has written the codes, only plenum rated cables may be run beneath the floor if that floor also is used as a cooling air plenum. The requirement is because toxic gasses from burning cabling insulation being pushed into the working space occupied by employees were a fire to ignite beneath the floor. However, Telco's now have a twenty year history of successfully using Very Early Smoke Detection Alarm (VESDA) systems. Many of these systems are designed to sample room air through PVC pipes placed under partial vacuum and then route that sampled air past a particle counter
{"title":"Firming up the Framing Why and How to Stiffen the Telecommunications Cabling Infrastructure","authors":"D. McMenamin","doi":"10.1109/INTLEC.2006.251645","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251645","url":null,"abstract":"The intent of this paper is to show the need for adequate bracing and framing of cable trays in the central office environment, particularly cable racks bearing power cables. Power busbars and cabling are the densest conductors in the telecommunications environment and everything in the central office is dependant on power. The paper will cover seismic influences on the cabling structures and the ways in which seismic displacement could result in systemic failure of the telecommunications systems if the mechanical support for the cabling or buswork is inadequate. The paper also will cover bracing and framing for busbars and busduct systems with text and illustrations. The paper will cover bracing and framing for cable trays including primary and secondary power cables, communication cables and optical fiber cable trays. Most telecommunications huts and CEVs are equipped with adequate cableways and so this paper is intended to speak mainly to central office cabling whether for wireline or wireless use and for data centers with DC powered systems. Finally, the paper will socialize an idea in the telecom community. Unfortunately, the way the National Fire Protection Association (NFPA) has written the codes, only plenum rated cables may be run beneath the floor if that floor also is used as a cooling air plenum. The requirement is because toxic gasses from burning cabling insulation being pushed into the working space occupied by employees were a fire to ignite beneath the floor. However, Telco's now have a twenty year history of successfully using Very Early Smoke Detection Alarm (VESDA) systems. Many of these systems are designed to sample room air through PVC pipes placed under partial vacuum and then route that sampled air past a particle counter","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129287829","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251590
L. Gaillac, D. Skaggs, N. Pinsky
This study focuses on the backup power requirements of telecommunications operations that are representative of many stationary power storage applications across the utility spectrum. The study evaluated the performance of a Zebra NaNiCl2 battery at Southern California Edison's (SCE) Electric Vehicle Technical Center (EVTC). EVTC's experience with backup power systems, battery expertise, and ISO 9001:2000-registration uniquely qualifies the organization for the project. The Zebra NaNiCl2 battery under the telecommunication test protocols produces encouraging results over ambient temperatures ranging from -20degC, to 75degC
{"title":"Sodium Nickel Chloride Battery Performance in a Stationary Application","authors":"L. Gaillac, D. Skaggs, N. Pinsky","doi":"10.1109/INTLEC.2006.251590","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251590","url":null,"abstract":"This study focuses on the backup power requirements of telecommunications operations that are representative of many stationary power storage applications across the utility spectrum. The study evaluated the performance of a Zebra NaNiCl2 battery at Southern California Edison's (SCE) Electric Vehicle Technical Center (EVTC). EVTC's experience with backup power systems, battery expertise, and ISO 9001:2000-registration uniquely qualifies the organization for the project. The Zebra NaNiCl2 battery under the telecommunication test protocols produces encouraging results over ambient temperatures ranging from -20degC, to 75degC","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"38 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121870720","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 : 2006-12-04DOI: 10.1109/INTLEC.2006.251646
Xingyu Cao, G. Moschopoulos, S. Bassan
A new auxiliary circuit for single switch, zero-voltage-transition pulse width modulated (ZVT-PWM) converters is proposed in this paper. This circuit can assist the zero-voltage-switching (ZVS) operation of the main converter switch with lower auxiliary switch switching losses than many previously proposed ZVT-PWM converters, but with less circulating current than that found in ZVT-PWM converters with resonant type auxiliary circuits. The paper will review the operation of auxiliary circuits in ZVT-PWM converters and then discuss the properties and characteristics of the new circuit. Experimental results obtained from a prototype of a ZVT-PWM boost converter with the new auxiliary circuit are presented
{"title":"A New ZVT-PWM Converter with Reduced Circulating Current Losses","authors":"Xingyu Cao, G. Moschopoulos, S. Bassan","doi":"10.1109/INTLEC.2006.251646","DOIUrl":"https://doi.org/10.1109/INTLEC.2006.251646","url":null,"abstract":"A new auxiliary circuit for single switch, zero-voltage-transition pulse width modulated (ZVT-PWM) converters is proposed in this paper. This circuit can assist the zero-voltage-switching (ZVS) operation of the main converter switch with lower auxiliary switch switching losses than many previously proposed ZVT-PWM converters, but with less circulating current than that found in ZVT-PWM converters with resonant type auxiliary circuits. The paper will review the operation of auxiliary circuits in ZVT-PWM converters and then discuss the properties and characteristics of the new circuit. Experimental results obtained from a prototype of a ZVT-PWM boost converter with the new auxiliary circuit are presented","PeriodicalId":356699,"journal":{"name":"INTELEC 06 - Twenty-Eighth International Telecommunications Energy Conference","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-12-04","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129921044","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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