Beyond price, large energy consumers are increasingly demanding higher value for their energy investment. For many businesses, especially those that are part of the burgeoning digital economy, this includes an expectation of energy delivered at higher levels of quality and reliability. These factors are driving enterprises on both the supply and demand side of energy to seek better strategies to manage the cost and quality of the energy product and the energy assets that produce, deliver, control, and consume it. However, to achieve this, all enterprises face three very large and fundamental challenges, which are the needs to: support the economic and efficient delivery, purchasing, and use of energy, guarantee higher levels of power quality and reliability the grid cannot currently deliver Supply the increasing demand for energy while establishing a market-based pricing system. The key to addressing all of these challenges is an Internet-enabled enterprise energy management (EEM) system that delivers real-time information and control through an efficient, economical, and scalable architecture.
{"title":"Right power, right price [enterprise energy management systems]","authors":"Brad Forth, T. Tobin","doi":"10.1109/67.993756","DOIUrl":"https://doi.org/10.1109/67.993756","url":null,"abstract":"Beyond price, large energy consumers are increasingly demanding higher value for their energy investment. For many businesses, especially those that are part of the burgeoning digital economy, this includes an expectation of energy delivered at higher levels of quality and reliability. These factors are driving enterprises on both the supply and demand side of energy to seek better strategies to manage the cost and quality of the energy product and the energy assets that produce, deliver, control, and consume it. However, to achieve this, all enterprises face three very large and fundamental challenges, which are the needs to: support the economic and efficient delivery, purchasing, and use of energy, guarantee higher levels of power quality and reliability the grid cannot currently deliver Supply the increasing demand for energy while establishing a market-based pricing system. The key to addressing all of these challenges is an Internet-enabled enterprise energy management (EEM) system that delivers real-time information and control through an efficient, economical, and scalable architecture.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"30 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126534680","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}
Circuit breakers in a utility network are designed to quickly isolate short-circuited equipment from the rest of the system. The short-circuit current changes with switching operations and with the addition and removal of generating sources. Hence, electric utilities must check their breakers periodically using computer simulation to ensure that the breakers are capable of interrupting the short-circuit currents. The recent proliferation of independent power producers (IPP) has made breaker-rating studies a much more routine procedure for utility engineers. The aim of these studies is to see if the existing circuit breakers are adequate when the proposed generators are put in service. The need for efficient and accurate breaker-rating software is greater now than ever. The benefit of computerized breaker-rating studies has been recognized for many years. Most utilities have breaker-rating software of some kind. What is not well known about breaker rating is the inherent difficulty in rating breakers using the sequence-network model that is commonly used for short-circuit studies. The breaker-rating program was improved by making the description of the breaker more flexible, universal, and easy to apply. This is the breaker connection model.Once breaker data is entered into a database, a breaker-rating program greatly reduces the time and effort required to ensure that breakers will work property in the event of a fault.
{"title":"Auto-check circuit breaker interrupting capabilities","authors":"T. C. Nguyen, S. Chan, R. Bailey, T. Nguyen","doi":"10.1109/67.976988","DOIUrl":"https://doi.org/10.1109/67.976988","url":null,"abstract":"Circuit breakers in a utility network are designed to quickly isolate short-circuited equipment from the rest of the system. The short-circuit current changes with switching operations and with the addition and removal of generating sources. Hence, electric utilities must check their breakers periodically using computer simulation to ensure that the breakers are capable of interrupting the short-circuit currents. The recent proliferation of independent power producers (IPP) has made breaker-rating studies a much more routine procedure for utility engineers. The aim of these studies is to see if the existing circuit breakers are adequate when the proposed generators are put in service. The need for efficient and accurate breaker-rating software is greater now than ever. The benefit of computerized breaker-rating studies has been recognized for many years. Most utilities have breaker-rating software of some kind. What is not well known about breaker rating is the inherent difficulty in rating breakers using the sequence-network model that is commonly used for short-circuit studies. The breaker-rating program was improved by making the description of the breaker more flexible, universal, and easy to apply. This is the breaker connection model.Once breaker data is entered into a database, a breaker-rating program greatly reduces the time and effort required to ensure that breakers will work property in the event of a fault.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"51 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131763902","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}
The detection and clearing of transformer faults are intimately connected to the primary switching that is available. Breakers are used both as locations for the current transformers to detect a fault and define the zone of protection and as a way of clearing the fault. The use of so many circuit breakers (CB) is usually not justified economically. As an alternative, motor-operated air-breaker switches (MOAB) instead of CBs are commonly used. A MOAB cannot interrupt a fault and usually can be opened only if the adjacent transmission line segment is de-energized. The growth and increased complexity of power system configurations has led to arrangements of MOABs with transformers and power transmission lines. This causes a difficult situation when relay engineers coordinate operation of relay sequence and MOABs. This article presents a solution for such a difficulty. The solution utilizes a local area supervisory protection (LASP) system to collect voltage and current data and then share data among the associated relays.
{"title":"Automating motor-operated air-breaker switches","authors":"M. Eissa","doi":"10.1109/67.993761","DOIUrl":"https://doi.org/10.1109/67.993761","url":null,"abstract":"The detection and clearing of transformer faults are intimately connected to the primary switching that is available. Breakers are used both as locations for the current transformers to detect a fault and define the zone of protection and as a way of clearing the fault. The use of so many circuit breakers (CB) is usually not justified economically. As an alternative, motor-operated air-breaker switches (MOAB) instead of CBs are commonly used. A MOAB cannot interrupt a fault and usually can be opened only if the adjacent transmission line segment is de-energized. The growth and increased complexity of power system configurations has led to arrangements of MOABs with transformers and power transmission lines. This causes a difficult situation when relay engineers coordinate operation of relay sequence and MOABs. This article presents a solution for such a difficulty. The solution utilizes a local area supervisory protection (LASP) system to collect voltage and current data and then share data among the associated relays.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129785132","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 : 2002-08-07DOI: 10.1109/MCAP.2002.976984
M. Gent
{"title":"Guest editor - an industry SRO is the future of electric reliability","authors":"M. Gent","doi":"10.1109/MCAP.2002.976984","DOIUrl":"https://doi.org/10.1109/MCAP.2002.976984","url":null,"abstract":"","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"32 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127769838","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 : 2002-08-07DOI: 10.1109/MCAP.2002.1018821
C. Gedemer
While traditional engineering applications have been used to address power quality, voltage, and various other issues within the distribution system, the presentation of these results normally has been within an engineering audience. However, today's engineer often needs to perform reliability studies and present the results to a much wider audience, including utility executives, managers, customer support, utility commissions, and even energy customers. As a result, reliability studies can become extremely important and often influence business decisions. This article addresses the challenges of results presentation to this larger audience, as well as preparation of the data required for a comprehensive study that will satisfy audience expectations.
{"title":"Reliability simulation shows results","authors":"C. Gedemer","doi":"10.1109/MCAP.2002.1018821","DOIUrl":"https://doi.org/10.1109/MCAP.2002.1018821","url":null,"abstract":"While traditional engineering applications have been used to address power quality, voltage, and various other issues within the distribution system, the presentation of these results normally has been within an engineering audience. However, today's engineer often needs to perform reliability studies and present the results to a much wider audience, including utility executives, managers, customer support, utility commissions, and even energy customers. As a result, reliability studies can become extremely important and often influence business decisions. This article addresses the challenges of results presentation to this larger audience, as well as preparation of the data required for a comprehensive study that will satisfy audience expectations.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126872630","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 : 2002-08-07DOI: 10.1109/MCAP.2002.1018818
S. Srivastava, K. Butler-Purry, N. Sarma
Network reconfiguration for restoration in a military shipboard power system is a very important task that is performed in order to restore loads as a result of battle damage or system faults. This article features an expert-system-based reconfiguration methodology for load restoration in shipboard power systems. The power system considered in the present study is based on the layout profile of a US surface combatant ship. The methodology developed will determine whether the loads that lost supply are restorable. When considering loads, it gives precedence to high priority loads. It also determines if there is any violation of current constraints of any cables and voltage constraints at load nodes. If the load is restorable, as suggested by an expert system, and there is no violation of any constraints, then the load is said to be restorable and the operation sequence required in restoring that load would be given as the output. A CAD drawing of the power system and a database of the system information has been developed using a geographic information system (GIS). A software tool incorporating failure assessment and expert system restoration methodology was developed using Visual C++, Multilogic Exsys Developer, Alternate Transients Program (ATP), and Microsoft Access. Microstation has been used for GIS. Various fault cases were designed, and the developed tool was used to run them and perform expert system restoration.
军用舰船电力系统的网络重构恢复是一项非常重要的任务，它是为了恢复由于作战损伤或系统故障而造成的负荷。本文提出了一种基于专家系统的船舶电力系统负荷恢复重构方法。在本研究中考虑的动力系统是基于美国水面作战舰艇的布局剖面。所开发的方法将确定失去供应的负载是否可以恢复。在考虑负载时，它优先考虑高优先级的负载。它还确定负载节点上是否存在违反任何电缆的电流约束和电压约束的情况。如果负载是可恢复的，如专家系统所建议的那样，并且没有违反任何约束，则称负载是可恢复的，并将恢复该负载所需的操作顺序作为输出。利用地理信息系统(GIS)建立了电力系统的CAD图和系统信息数据库。采用Visual c++、Multilogic Exsys Developer、Alternate Transients Program (ATP)和Microsoft Access开发了一个集成故障评估和专家系统恢复方法的软件工具。微站已被用于地理信息系统。设计了各种故障案例，并利用开发的工具对其进行了运行和专家系统恢复。
{"title":"Shipboard power restored for active duty","authors":"S. Srivastava, K. Butler-Purry, N. Sarma","doi":"10.1109/MCAP.2002.1018818","DOIUrl":"https://doi.org/10.1109/MCAP.2002.1018818","url":null,"abstract":"Network reconfiguration for restoration in a military shipboard power system is a very important task that is performed in order to restore loads as a result of battle damage or system faults. This article features an expert-system-based reconfiguration methodology for load restoration in shipboard power systems. The power system considered in the present study is based on the layout profile of a US surface combatant ship. The methodology developed will determine whether the loads that lost supply are restorable. When considering loads, it gives precedence to high priority loads. It also determines if there is any violation of current constraints of any cables and voltage constraints at load nodes. If the load is restorable, as suggested by an expert system, and there is no violation of any constraints, then the load is said to be restorable and the operation sequence required in restoring that load would be given as the output. A CAD drawing of the power system and a database of the system information has been developed using a geographic information system (GIS). A software tool incorporating failure assessment and expert system restoration methodology was developed using Visual C++, Multilogic Exsys Developer, Alternate Transients Program (ATP), and Microsoft Access. Microstation has been used for GIS. Various fault cases were designed, and the developed tool was used to run them and perform expert system restoration.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"119 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129506171","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 : 2002-08-07DOI: 10.1109/MCAP.2002.1018824
M. Shahidehpour
Mathematical programming techniques constitute powerful optimization tools for power systems control, operation, and planning. For many years, traditional power system problems (such as economic dispatch, unit commitment, hydrothermal coordination, state estimation, transmission and distribution expansion planning, and optimal power flow) were formulated and solved by applying mathematical programming techniques. More recently, in restructured power systems, electricity market problems (such as market clearing price, price-based generation scheduling, portfolio optimization, risk management, asset valuation, arbitrage, and strategic bidding) have been formulated and solved by mathematical programming techniques. Building and Solving Mathematical Programming Models in Engineering and Science is a welcome addition to the series of publications on mathematical programming applications to engineering problems. The authors have years of experience in the modeling and the solution of practical cases. Numerous discussions on the system optimization and the examples pertinent to power systems make the book suitable for students, faculty, engineers, and consultants with special interest in solving electric power systems problems. The book emphasizes the engineering applications of mathematical programming. Many of the topics covered by this book focus on the formulation and modeling of engineering problems as opposed to the theoretical aspects of solution algorithms. The book applies an algebraic environment that makes it possible to formulate an engineering problem and to modify easily its formulation so that many solution alternatives can be explored and analyzed. This feature of the book is essential to many applications in engineering, as it avoids tedious coding requirements of
{"title":"Building and solving mathematical programming models in engineering and science [Book Review]","authors":"M. Shahidehpour","doi":"10.1109/MCAP.2002.1018824","DOIUrl":"https://doi.org/10.1109/MCAP.2002.1018824","url":null,"abstract":"Mathematical programming techniques constitute powerful optimization tools for power systems control, operation, and planning. For many years, traditional power system problems (such as economic dispatch, unit commitment, hydrothermal coordination, state estimation, transmission and distribution expansion planning, and optimal power flow) were formulated and solved by applying mathematical programming techniques. More recently, in restructured power systems, electricity market problems (such as market clearing price, price-based generation scheduling, portfolio optimization, risk management, asset valuation, arbitrage, and strategic bidding) have been formulated and solved by mathematical programming techniques. Building and Solving Mathematical Programming Models in Engineering and Science is a welcome addition to the series of publications on mathematical programming applications to engineering problems. The authors have years of experience in the modeling and the solution of practical cases. Numerous discussions on the system optimization and the examples pertinent to power systems make the book suitable for students, faculty, engineers, and consultants with special interest in solving electric power systems problems. The book emphasizes the engineering applications of mathematical programming. Many of the topics covered by this book focus on the formulation and modeling of engineering problems as opposed to the theoretical aspects of solution algorithms. The book applies an algebraic environment that makes it possible to formulate an engineering problem and to modify easily its formulation so that many solution alternatives can be explored and analyzed. This feature of the book is essential to many applications in engineering, as it avoids tedious coding requirements of","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"45 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116895434","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 : 2002-08-07DOI: 10.1109/MCAP.2002.1018823
L. Kojovic
Innovative Rogowski coils enable the design of advanced protection systems when used with new multifunction relays and fiberoptic communication. The protection systems have faster response times to faults and can easily adjust to load and/or power system configuration changes. Since the new Rogowski coils are very accurate and do not saturate, protection levels can be set to lower fault current thresholds, reducing the stress on the protected equipment. The whole system is immune to external magnetic fields and has self-testing logic. No wiring is necessary.
{"title":"PCB Rogowski coils benefit relay protection","authors":"L. Kojovic","doi":"10.1109/MCAP.2002.1018823","DOIUrl":"https://doi.org/10.1109/MCAP.2002.1018823","url":null,"abstract":"Innovative Rogowski coils enable the design of advanced protection systems when used with new multifunction relays and fiberoptic communication. The protection systems have faster response times to faults and can easily adjust to load and/or power system configuration changes. Since the new Rogowski coils are very accurate and do not saturate, protection levels can be set to lower fault current thresholds, reducing the stress on the protected equipment. The whole system is immune to external magnetic fields and has self-testing logic. No wiring is necessary.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"16 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124613836","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}
US domestic power utilities are faced with over 600000 kilometers of solid-dielectric underground cables, virtually all of which do not meet the reliability standards required of a twenty-first century economy. Diagnostic testing methods are being developed and commercialized that are intended to prioritize the 600000-kilometer cable replacement effort. Over 90% of the pre1980 vintage cables are single-phase underground residential distribution (URD) cable. An economic model is presented that allows an objective comparison of any testing technique and the alternatives, which include replacing the suspect circuits or using commercially available life-extension technologies. Available diagnostic technology is not an economically viable option for URD cables. An alternative computer-based tool is now available that aids in the prioritization efforts at a small fraction of the cost of performing diagnostic testing. The tool provides a strategic reliability analysis (SRA), which allows the mining of the utility's own data to definitively answer the critical strategic questions.
{"title":"Prioritizing reliability for underground distribution","authors":"G. Bertini","doi":"10.1109/67.976989","DOIUrl":"https://doi.org/10.1109/67.976989","url":null,"abstract":"US domestic power utilities are faced with over 600000 kilometers of solid-dielectric underground cables, virtually all of which do not meet the reliability standards required of a twenty-first century economy. Diagnostic testing methods are being developed and commercialized that are intended to prioritize the 600000-kilometer cable replacement effort. Over 90% of the pre1980 vintage cables are single-phase underground residential distribution (URD) cable. An economic model is presented that allows an objective comparison of any testing technique and the alternatives, which include replacing the suspect circuits or using commercially available life-extension technologies. Available diagnostic technology is not an economically viable option for URD cables. An alternative computer-based tool is now available that aids in the prioritization efforts at a small fraction of the cost of performing diagnostic testing. The tool provides a strategic reliability analysis (SRA), which allows the mining of the utility's own data to definitively answer the critical strategic questions.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131200389","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}
At energy markets driven by deregulation and liberalization processes under way in central and eastern European countries, information and its processing is gaining key importance. Energy trading will require risk management of multiple aspects of power engineering, and decision-making and implementation-support tools will be increasingly helpful. The need for computer support is of particular concern to network companies. Just like control and supervision systems, computer support is subject to far-reaching technical and functional integration. The dynamic development and dissemination of microcomputing technology as well as the transition to a market-oriented approach of power engineering makes this possible, and the introduction of automatic control and supervision systems at all voltage levels is required. This includes distribution lines and substations. The cost of such solutions is decreasing at the present time and may be treated as justified costs in networking power utilities due to increased requirements for energy supply and customer services. This article deals with some main issues of automatic control and supervision systems development and their integration into the general functions of networking power companies. It also discusses common technical frameworks, including their potential application at the national power engineering level.
{"title":"Automated network control and supervision","authors":"A. Augusiak, W. Kamrat","doi":"10.1109/67.976987","DOIUrl":"https://doi.org/10.1109/67.976987","url":null,"abstract":"At energy markets driven by deregulation and liberalization processes under way in central and eastern European countries, information and its processing is gaining key importance. Energy trading will require risk management of multiple aspects of power engineering, and decision-making and implementation-support tools will be increasingly helpful. The need for computer support is of particular concern to network companies. Just like control and supervision systems, computer support is subject to far-reaching technical and functional integration. The dynamic development and dissemination of microcomputing technology as well as the transition to a market-oriented approach of power engineering makes this possible, and the introduction of automatic control and supervision systems at all voltage levels is required. This includes distribution lines and substations. The cost of such solutions is decreasing at the present time and may be treated as justified costs in networking power utilities due to increased requirements for energy supply and customer services. This article deals with some main issues of automatic control and supervision systems development and their integration into the general functions of networking power companies. It also discusses common technical frameworks, including their potential application at the national power engineering level.","PeriodicalId":435675,"journal":{"name":"IEEE Computer Applications in Power","volume":"14 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-08-07","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122065502","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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