Pub Date : 1998-01-19DOI: 10.1109/RAMS.1998.653706
R. Kumar, S. Rai, J. Trahan
Software quality modeling involves identifying fault-prone modules and predicting the number of errors in the early stages of the software development life cycle. This paper investigates the viability of several neural network techniques for software quality evaluation (SQE). We have implemented a principal component analysis technique (used in SQE) with two different neural network training rules, and have classified software modules as fault-prone or nonfault-prone using software complexity metric data. Our results reveal that neural network techniques provide a good management tool in a software engineering environment.
{"title":"Neural-network techniques for software-quality evaluation","authors":"R. Kumar, S. Rai, J. Trahan","doi":"10.1109/RAMS.1998.653706","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653706","url":null,"abstract":"Software quality modeling involves identifying fault-prone modules and predicting the number of errors in the early stages of the software development life cycle. This paper investigates the viability of several neural network techniques for software quality evaluation (SQE). We have implemented a principal component analysis technique (used in SQE) with two different neural network training rules, and have classified software modules as fault-prone or nonfault-prone using software complexity metric data. Our results reveal that neural network techniques provide a good management tool in a software engineering environment.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"62 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125840007","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653547
J. A. Miller, J. Moss, T. Kiang, V. Loll, H. C. Benski
IEC (International Electrotechnical Commission) is a worldwide federation of standards bodies composed of National Committees in some 50 countries with more than 200 TCs (Technical Committees). TC56 is one of the IEC/TCs dedicated to the generic technical discipline on dependability. TC56 is involved in standardization in the field of availability performance (reliability, maintainability and maintenance support) to provide suppliers, buyers and users with systematic and cost-effective dependability based approaches, methods, and tools for appropriate assessment and risk management of technological products and systems. TC56 standards are developed by consensus with contributions from participating National Committees represented at TC56 International Standards forum which meets annually. These standards are used in major international contracts. They also serve as dependability project management and technical guidance to companies seeking global markets. The objective of this TC56 Panel Session at the 1998 RAMS is to bring together a group of international experts on dependability standards, to share ideas and experiences, and to present an outlook into the future concerning International Standards work on dependability. The issues, benefits and implications in doing business internationally with existing and upcoming dependability standards are addressed.
{"title":"Dependability Standards: An International Cooperation","authors":"J. A. Miller, J. Moss, T. Kiang, V. Loll, H. C. Benski","doi":"10.1109/RAMS.1998.653547","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653547","url":null,"abstract":"IEC (International Electrotechnical Commission) is a worldwide federation of standards bodies composed of National Committees in some 50 countries with more than 200 TCs (Technical Committees). TC56 is one of the IEC/TCs dedicated to the generic technical discipline on dependability. TC56 is involved in standardization in the field of availability performance (reliability, maintainability and maintenance support) to provide suppliers, buyers and users with systematic and cost-effective dependability based approaches, methods, and tools for appropriate assessment and risk management of technological products and systems. TC56 standards are developed by consensus with contributions from participating National Committees represented at TC56 International Standards forum which meets annually. These standards are used in major international contracts. They also serve as dependability project management and technical guidance to companies seeking global markets. The objective of this TC56 Panel Session at the 1998 RAMS is to bring together a group of international experts on dependability standards, to share ideas and experiences, and to present an outlook into the future concerning International Standards work on dependability. The issues, benefits and implications in doing business internationally with existing and upcoming dependability standards are addressed.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"162 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128087878","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653801
M. Garnero, F. Beaudouin, J. Delbos
The topic of this paper is the optimization of inspection intervals for the motor-pump set of the AFW system (auxiliary feedwater system) in a nuclear plant. The report focuses on plain hydrodynamic bearings and thrusts. The bearings inspection task requires the disassembly of the pump which is expensive and has not proved to be necessary so far. This paper shows the advantages of the combined use of experts judgments (for the selection of external influent parameters), physical modelling (for the quantification of wear) and operating experience (for the evaluation of failure rates). Physical modelling is very important indeed when poor information is available and especially when experts opinions are missing due to a poor number of operating hours.
{"title":"Optimization of bearing-inspection intervals","authors":"M. Garnero, F. Beaudouin, J. Delbos","doi":"10.1109/RAMS.1998.653801","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653801","url":null,"abstract":"The topic of this paper is the optimization of inspection intervals for the motor-pump set of the AFW system (auxiliary feedwater system) in a nuclear plant. The report focuses on plain hydrodynamic bearings and thrusts. The bearings inspection task requires the disassembly of the pump which is expensive and has not proved to be necessary so far. This paper shows the advantages of the combined use of experts judgments (for the selection of external influent parameters), physical modelling (for the quantification of wear) and operating experience (for the evaluation of failure rates). Physical modelling is very important indeed when poor information is available and especially when experts opinions are missing due to a poor number of operating hours.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"271 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124392124","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653750
M. Deck
In the context of software engineering, the IEEE defines reliability as "the ability of a system or component to perform its required functions under stated conditions for a specified period of time". The author believes that improving the development process is really the longer end of the lever. The Cleanroom approach, initially conceived at IBM's Federal Systems Division, is a proven set of principles, practices, and techniques for reducing the cost to develop highly reliable software. While this paper does not explain all of what Cleanroom offers, the author gives an overview of the approach and cite some examples of its use with which he is familiar.
{"title":"Software reliability and the \"Cleanroom\" approach: a position paper","authors":"M. Deck","doi":"10.1109/RAMS.1998.653750","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653750","url":null,"abstract":"In the context of software engineering, the IEEE defines reliability as \"the ability of a system or component to perform its required functions under stated conditions for a specified period of time\". The author believes that improving the development process is really the longer end of the lever. The Cleanroom approach, initially conceived at IBM's Federal Systems Division, is a proven set of principles, practices, and techniques for reducing the cost to develop highly reliable software. While this paper does not explain all of what Cleanroom offers, the author gives an overview of the approach and cite some examples of its use with which he is familiar.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"192 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132834338","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653549
M. Silverman
Accelerated reliability testing is one of the fastest growing segments of the testing industry because it enables the user to determine the reliability of a product quicker, therefore being able to affect the design quicker. HALT and HASS (highly accelerated stress screen) are special types of accelerated reliability techniques that are very effective and are being used by companies around the world from many different industries. HALT is used at the design stage of a project to quickly expose the weakpoints of a design so that the product can be re-designed to remove these weakpoints, thereby expanding the margins of the design. All of this can be achieved at a minimal cost increase, if any at all. HASS is used at the manufacturing stage of a project to quickly expose any manufacturing flaws that a particular sample may have. The two principle stresses used during HALT and HASS are rapid temperature transitions and OmniAxial (6 degree-of-freedom) random vibration. This paper analyzes HALT and HASS data from 33 different companies from a variety of industries and illustrates the following concepts: HALT can be applied to a wide variety of electrical and electro-mechanical products. Products today are much more robust than in the past and, therefore, these methods are necessary to improve product reliability. Random vibration is much more effective than temperature cycling for accelerating defects, and the combined environment of random vibration and temperature cycling is even more effective still. The types of failures that HALT and HASS discover are the same types of failures that are found in the field.
{"title":"Summary of HALT and HASS results at an accelerated reliability test center","authors":"M. Silverman","doi":"10.1109/RAMS.1998.653549","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653549","url":null,"abstract":"Accelerated reliability testing is one of the fastest growing segments of the testing industry because it enables the user to determine the reliability of a product quicker, therefore being able to affect the design quicker. HALT and HASS (highly accelerated stress screen) are special types of accelerated reliability techniques that are very effective and are being used by companies around the world from many different industries. HALT is used at the design stage of a project to quickly expose the weakpoints of a design so that the product can be re-designed to remove these weakpoints, thereby expanding the margins of the design. All of this can be achieved at a minimal cost increase, if any at all. HASS is used at the manufacturing stage of a project to quickly expose any manufacturing flaws that a particular sample may have. The two principle stresses used during HALT and HASS are rapid temperature transitions and OmniAxial (6 degree-of-freedom) random vibration. This paper analyzes HALT and HASS data from 33 different companies from a variety of industries and illustrates the following concepts: HALT can be applied to a wide variety of electrical and electro-mechanical products. Products today are much more robust than in the past and, therefore, these methods are necessary to improve product reliability. Random vibration is much more effective than temperature cycling for accelerating defects, and the combined environment of random vibration and temperature cycling is even more effective still. The types of failures that HALT and HASS discover are the same types of failures that are found in the field.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130441825","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653808
A. Benso, Maurizio Rebaudengo, L. Impagliazzo, P. Marmo
Fault injection is become a popular approach to evaluate and possibly to improve the dependability of computer-based systems. One of the main issues to be solved when setting up a fault injection experiment is the generation of a list of faults to be injected, really representative of the whole set of possible faults. This paper proposes a set of collapsing rules based on the analysis of the assembly code and of the behavior of a fault free run of the system, useful to reduce the fault list length and the fault injection time without decreasing the accuracy of the results. The approach is suitable to be adapted for microprocessor-based systems and is independent on the method used to generate the fault list to be collapsed.
{"title":"Fault-list collapsing for fault-injection experiments","authors":"A. Benso, Maurizio Rebaudengo, L. Impagliazzo, P. Marmo","doi":"10.1109/RAMS.1998.653808","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653808","url":null,"abstract":"Fault injection is become a popular approach to evaluate and possibly to improve the dependability of computer-based systems. One of the main issues to be solved when setting up a fault injection experiment is the generation of a list of faults to be injected, really representative of the whole set of possible faults. This paper proposes a set of collapsing rules based on the analysis of the assembly code and of the behavior of a fault free run of the system, useful to reduce the fault list length and the fault injection time without decreasing the accuracy of the results. The approach is suitable to be adapted for microprocessor-based systems and is independent on the method used to generate the fault list to be collapsed.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"77 7 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130676855","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653799
P. Hammett, K. Majeske, J. Baron
This paper presents a new paradigm for the validation phase of product and process development. Manufacturers that continue to embrace new methodologies and business practices will not only remain competitive in the global market but also set the benchmark for competition. By using an integrated validation approach like functional build, manufacturers may accelerate the product development life cycle while saving costs in manufacturing process development.
{"title":"Functional build: integrating automotive body-design and process-development","authors":"P. Hammett, K. Majeske, J. Baron","doi":"10.1109/RAMS.1998.653799","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653799","url":null,"abstract":"This paper presents a new paradigm for the validation phase of product and process development. Manufacturers that continue to embrace new methodologies and business practices will not only remain competitive in the global market but also set the benchmark for competition. By using an integrated validation approach like functional build, manufacturers may accelerate the product development life cycle while saving costs in manufacturing process development.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"44 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122748676","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653793
M. Lively
Electricity provides a unique opportunity to determine how much consumers will actually pay for product reliability. The electric network is robust and can generally survive the failure of several components. As these components fail, sensing devices on the portion of the network still operating can continually produce reliability indices. The central reliability index, system frequency, can be used with other reliability indices to set the price for electricity on a concurrent, real-time basis. Electric systems now operate in a command and control environment. A system operator makes decisions to match the level of total generation and the level of total load, generally controlling the production of electricity, but sometimes also controlling the use of electricity. With the increase in competition, electric systems need to add economic incentives to the tools the system operator has available to achieve the real-time matching of generation and load. A dynamic reliability-based price for electricity would allow customers to make the explicit choice between reliability of service and the price of electricity. Similarly, independent equipment owners could make economic decisions to increase system reliability at the cost of installing and operating equipment. Such a dynamic pricing mechanism would provide an economic negative feedback loop that determines both economically and physically the optimal operating level.
{"title":"Real-time reliability-based electricity pricing","authors":"M. Lively","doi":"10.1109/RAMS.1998.653793","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653793","url":null,"abstract":"Electricity provides a unique opportunity to determine how much consumers will actually pay for product reliability. The electric network is robust and can generally survive the failure of several components. As these components fail, sensing devices on the portion of the network still operating can continually produce reliability indices. The central reliability index, system frequency, can be used with other reliability indices to set the price for electricity on a concurrent, real-time basis. Electric systems now operate in a command and control environment. A system operator makes decisions to match the level of total generation and the level of total load, generally controlling the production of electricity, but sometimes also controlling the use of electricity. With the increase in competition, electric systems need to add economic incentives to the tools the system operator has available to achieve the real-time matching of generation and load. A dynamic reliability-based price for electricity would allow customers to make the explicit choice between reliability of service and the price of electricity. Similarly, independent equipment owners could make economic decisions to increase system reliability at the cost of installing and operating equipment. Such a dynamic pricing mechanism would provide an economic negative feedback loop that determines both economically and physically the optimal operating level.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"70 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123037573","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653738
D. Kececioglu, Jiliang Zhang
The deterministic Goodman diagram, which reflects the relationship among the mean stress, the alternating stress and the appropriate strength properties of a material, is commonly used to bring the influence of the nonzero stress ratio of the alternating to the mean stress into consideration. This is important because many mechanical components are subjected to combined stresses. In this paper, three methods are presented to deal with both the scatter of the loading and of the material strength. In the first method, the distributional Goodman and other combined stress failure relationships are obtained and used, based on the normal approximation and the binary synthesis of distributions. In the second method, the distributional Goodman and other combined stress failure relationships are obtained and used to find the state limit function. Then, the first order second moment algorithm is employed to determine the reliability. In the third method, the distributional Goodman diagram is used directly with the stress ratio mean, obtained by Taylor's expansion about the mean vector. A combined bending-torsion load problem is solved as an application of the methods presented here.
{"title":"Combined-stress fatigue reliability analysis","authors":"D. Kececioglu, Jiliang Zhang","doi":"10.1109/RAMS.1998.653738","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653738","url":null,"abstract":"The deterministic Goodman diagram, which reflects the relationship among the mean stress, the alternating stress and the appropriate strength properties of a material, is commonly used to bring the influence of the nonzero stress ratio of the alternating to the mean stress into consideration. This is important because many mechanical components are subjected to combined stresses. In this paper, three methods are presented to deal with both the scatter of the loading and of the material strength. In the first method, the distributional Goodman and other combined stress failure relationships are obtained and used, based on the normal approximation and the binary synthesis of distributions. In the second method, the distributional Goodman and other combined stress failure relationships are obtained and used to find the state limit function. Then, the first order second moment algorithm is employed to determine the reliability. In the third method, the distributional Goodman diagram is used directly with the stress ratio mean, obtained by Taylor's expansion about the mean vector. A combined bending-torsion load problem is solved as an application of the methods presented here.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122024419","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 : 1998-01-19DOI: 10.1109/RAMS.1998.653729
D. Tang, M. Hecht, J. Handal, L. Czekalski
MEADEP (measure dependability) is a user-friendly dependability evaluation tool for measurement-based analysis of computing systems including both hardware and software. Features of MEADEP are: a data processor for converting data in various formats (records with a number of fields stored in a commercial database format) to the MEADEP format, a statistical analysis module for graphical data presentation and parameter estimation, a graphical modeling interface for constructing reliability block and Markov diagrams, and a model solution module for availability/reliability calculation with graphical parametric analysis. Use of the tool on failure data from measurements can provide quantitative assessments of dependability for critical systems, while greatly reducing requirements for specialized skills in data processing, analysis, and modeling from the user. MEADEP has been applied to evaluate dependability for several air traffic control systems (ATC) and results produced by MEADEP have provided valuable feedback to the program management of these critical systems.
{"title":"MEADEP and its applications in evaluating dependability for air traffic control systems","authors":"D. Tang, M. Hecht, J. Handal, L. Czekalski","doi":"10.1109/RAMS.1998.653729","DOIUrl":"https://doi.org/10.1109/RAMS.1998.653729","url":null,"abstract":"MEADEP (measure dependability) is a user-friendly dependability evaluation tool for measurement-based analysis of computing systems including both hardware and software. Features of MEADEP are: a data processor for converting data in various formats (records with a number of fields stored in a commercial database format) to the MEADEP format, a statistical analysis module for graphical data presentation and parameter estimation, a graphical modeling interface for constructing reliability block and Markov diagrams, and a model solution module for availability/reliability calculation with graphical parametric analysis. Use of the tool on failure data from measurements can provide quantitative assessments of dependability for critical systems, while greatly reducing requirements for specialized skills in data processing, analysis, and modeling from the user. MEADEP has been applied to evaluate dependability for several air traffic control systems (ATC) and results produced by MEADEP have provided valuable feedback to the program management of these critical systems.","PeriodicalId":275301,"journal":{"name":"Annual Reliability and Maintainability Symposium. 1998 Proceedings. International Symposium on Product Quality and Integrity","volume":"20 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"1998-01-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131969242","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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