Pub Date : 2002-12-05DOI: 10.1109/SEW.2002.1199445
K. Gross, V. Bhardwaj, R. Bickford
Software aging is a phenomenon, usually caused by resource contention, that can cause mission critical and business critical computer systems to hang, panic, or suffer performance degradation. If the incipience or onset of software aging mechanisms can be reliably detected in advance of performance degradation, corrective actions can be taken to prevent system hangs, or dynamic failover events can be triggered in fault tolerant systems. In the 1990 's the U.S. Dept. of Energy and NASA funded development of an advanced statistical pattern recognition method called the multivariate state estimation technique (MSET) for proactive online detection of dynamic sensor and signal anomalies in nuclear power plants and Space Shuttle Main Engine telemetry data. The present investigation was undertaken to investigate the feasibility and practicability of applying MSET for realtime proactive detection of software aging mechanisms in complex, multiCPU servers. The procedure uses MSET for model based parameter estimation in conjunction with statistical fault detection and Bayesian fault decision processing. A realtime software telemetry harness was designed to continuously sample over 50 performance metrics related to computer system load, throughput, queue lengths, and transaction latencies. A series of fault injection experiments was conducted using a "memory leak" injector tool with controllable parasitic resource consumption rates. MSET was able to reliably detect the onset of resource contention problems with high sensitivity and excellent false-alarm avoidance. Spin-off applications of this NASA-funded innovation for business critical eCommerce servers are described.
{"title":"Proactive detection of software aging mechanisms in performance critical computers","authors":"K. Gross, V. Bhardwaj, R. Bickford","doi":"10.1109/SEW.2002.1199445","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199445","url":null,"abstract":"Software aging is a phenomenon, usually caused by resource contention, that can cause mission critical and business critical computer systems to hang, panic, or suffer performance degradation. If the incipience or onset of software aging mechanisms can be reliably detected in advance of performance degradation, corrective actions can be taken to prevent system hangs, or dynamic failover events can be triggered in fault tolerant systems. In the 1990 's the U.S. Dept. of Energy and NASA funded development of an advanced statistical pattern recognition method called the multivariate state estimation technique (MSET) for proactive online detection of dynamic sensor and signal anomalies in nuclear power plants and Space Shuttle Main Engine telemetry data. The present investigation was undertaken to investigate the feasibility and practicability of applying MSET for realtime proactive detection of software aging mechanisms in complex, multiCPU servers. The procedure uses MSET for model based parameter estimation in conjunction with statistical fault detection and Bayesian fault decision processing. A realtime software telemetry harness was designed to continuously sample over 50 performance metrics related to computer system load, throughput, queue lengths, and transaction latencies. A series of fault injection experiments was conducted using a \"memory leak\" injector tool with controllable parasitic resource consumption rates. MSET was able to reliably detect the onset of resource contention problems with high sensitivity and excellent false-alarm avoidance. Spin-off applications of this NASA-funded innovation for business critical eCommerce servers are described.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130122981","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199455
P. Deussen, G. Din, I. Schieferdecker
One of the most provocative research areas in software engineering field is the testing of modern component based distributed applications in order to assure required quality parameters. Dynamic interactions and structural embedding, run-time loadable configurations, and services that can be deployed in arbitrary executions environments results in an increased complexity. Moreover, that the variety of possible states and behaviors becomes unpredictable. Thus, since testing during the development phase is always applied in simulated environments, it is almost impossible to detect faults, which appear under real condition, during production phase of a system. We therefore aim at concepts and methodologies that achieve on-line testing of distributed component based systems in their production phase. In comparison with off-line testing (i.e. testing that takes place during system development), on-line testing addresses particular aspects of the behavior of distributed systems, such as: functionality under limited time and resources available, complex transactions that are performed between components provided by different vendors, deployment, and composition of different services.
{"title":"An on-line test platform for component-based systems","authors":"P. Deussen, G. Din, I. Schieferdecker","doi":"10.1109/SEW.2002.1199455","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199455","url":null,"abstract":"One of the most provocative research areas in software engineering field is the testing of modern component based distributed applications in order to assure required quality parameters. Dynamic interactions and structural embedding, run-time loadable configurations, and services that can be deployed in arbitrary executions environments results in an increased complexity. Moreover, that the variety of possible states and behaviors becomes unpredictable. Thus, since testing during the development phase is always applied in simulated environments, it is almost impossible to detect faults, which appear under real condition, during production phase of a system. We therefore aim at concepts and methodologies that achieve on-line testing of distributed component based systems in their production phase. In comparison with off-line testing (i.e. testing that takes place during system development), on-line testing addresses particular aspects of the behavior of distributed systems, such as: functionality under limited time and resources available, complex transactions that are performed between components provided by different vendors, deployment, and composition of different services.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"9 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124859156","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199452
S. Liu
A new approach to rigorously reviewing formal specifications to ensure their internal consistency and validity is forwarded. This approach includes four steps: (1) deriving properties as review targets based on the syntax and semantics of the specification, (2) building a review task tree to present all the necessary review tasks for each property, (3) carrying out reviews based on the review task tree, and (4) analyzing the review results to determine whether faults are detected or not. We apply this technique to the SOFL specification language, which is an integrated formalism of VDM, Petri nets, and data flow diagrams to discuss how each step is performed.
{"title":"A rigorous approach to reviewing formal specifications","authors":"S. Liu","doi":"10.1109/SEW.2002.1199452","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199452","url":null,"abstract":"A new approach to rigorously reviewing formal specifications to ensure their internal consistency and validity is forwarded. This approach includes four steps: (1) deriving properties as review targets based on the syntax and semantics of the specification, (2) building a review task tree to present all the necessary review tasks for each property, (3) carrying out reviews based on the review task tree, and (4) analyzing the review results to determine whether faults are detected or not. We apply this technique to the SOFL specification language, which is an integrated formalism of VDM, Petri nets, and data flow diagrams to discuss how each step is performed.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"47 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121567909","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199475
R. Tvedt, M. Lindvall, P. Costa
Software systems often undergo changes. Changes are necessary not only to fix defects but also to accommodate new features demanded by users. Most of the time, changes are made under schedule and budget constraints and developers lack time to study the software architecture and select the best way to implement the changes. As a result, the code degenerates, making it differ from the planned design. The time spent on the planned design to create architecture to satisfy certain properties is lost, and the systems may not satisfy those properties any more. We describe an approach to systematically detect and correct deviations from the planned design as soon as possible based on architectural guidelines. We also describe a case study, in which the process was applied.
{"title":"A process for software architecture evaluation using metrics","authors":"R. Tvedt, M. Lindvall, P. Costa","doi":"10.1109/SEW.2002.1199475","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199475","url":null,"abstract":"Software systems often undergo changes. Changes are necessary not only to fix defects but also to accommodate new features demanded by users. Most of the time, changes are made under schedule and budget constraints and developers lack time to study the software architecture and select the best way to implement the changes. As a result, the code degenerates, making it differ from the planned design. The time spent on the planned design to create architecture to satisfy certain properties is lost, and the systems may not satisfy those properties any more. We describe an approach to systematically detect and correct deviations from the planned design as soon as possible based on architectural guidelines. We also describe a case study, in which the process was applied.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"50 3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123692272","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199447
M. M. Hugue, James M. Purtilo
Hardware and software components are often treated as distinct entities with different development and run-time profiles. Yet, these key design elements and components of embedded and stand-alone computing systems have an inherent vulnerability to human error. Since manufacturers of hardware make extensive use of software in producing masses of integrated devices exhibiting independent failure rates, the rapidly growing software engineering community has begun to embrace the rule-and-tool based approach of the professional engineer. Adoption of iterative design rules, tools, component reuse, and simulation/testing methodologies into every process and component required by a complex systems for highly dependable applications has the potential to minimize the propagation of human-made latent errors into fielded systems. By identifying and employing design patterns for dependability, we believe that we can mitigate the effects of human agents as single points of failure and achieve the desired dependability of the final product.
{"title":"Guerrilla tactics: motivating design patterns for high-dependability applications","authors":"M. M. Hugue, James M. Purtilo","doi":"10.1109/SEW.2002.1199447","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199447","url":null,"abstract":"Hardware and software components are often treated as distinct entities with different development and run-time profiles. Yet, these key design elements and components of embedded and stand-alone computing systems have an inherent vulnerability to human error. Since manufacturers of hardware make extensive use of software in producing masses of integrated devices exhibiting independent failure rates, the rapidly growing software engineering community has begun to embrace the rule-and-tool based approach of the professional engineer. Adoption of iterative design rules, tools, component reuse, and simulation/testing methodologies into every process and component required by a complex systems for highly dependable applications has the potential to minimize the propagation of human-made latent errors into fielded systems. By identifying and employing design patterns for dependability, we believe that we can mitigate the effects of human agents as single points of failure and achieve the desired dependability of the final product.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133047650","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199453
Carol S. Smidts, B. Cukic, Erdogan Gunel, M. Li, Harshinder Singh
We suggest that subjective reliability estimation from the development lifecycle, based on observed behavior or the reflection of one's belief in the system quality, be included in certification. In statistical terms, we hypothesize that a system failure occurs with the estimated probability. Presumed reliability needs to be corroborated by statistical testing during the reliability certification phase. As evidence relevant to the hypothesis increases, we change the degree of belief in the hypothesis. Depending on the corroboration evidence, the system is either certified or rejected. The advantage of the proposed theory is an economically acceptable number of required system certification tests, even for high assurance systems so far considered impossible to certify.
{"title":"Software reliability corroboration","authors":"Carol S. Smidts, B. Cukic, Erdogan Gunel, M. Li, Harshinder Singh","doi":"10.1109/SEW.2002.1199453","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199453","url":null,"abstract":"We suggest that subjective reliability estimation from the development lifecycle, based on observed behavior or the reflection of one's belief in the system quality, be included in certification. In statistical terms, we hypothesize that a system failure occurs with the estimated probability. Presumed reliability needs to be corroborated by statistical testing during the reliability certification phase. As evidence relevant to the hypothesis increases, we change the degree of belief in the hypothesis. Depending on the corroboration evidence, the system is either certified or rejected. The advantage of the proposed theory is an economically acceptable number of required system certification tests, even for high assurance systems so far considered impossible to certify.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127788665","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199446
Massood Towhidnejad, D. Wallace, A. Gallo
We present a study on software fault tree analysis (SFTA) conducted at the Software Assurance Technology Center at NASA Goddard Space Flight Center. While researchers have made various attempts at SFTA, software assurance practitioners have been slow to adopt it. One reason is the intense manual effort needed to identify and draw the fault trees for the code of large software projects. Another is the lack of commercial tools to assist in the technique for software. Most SFTA research efforts have been directed at requirements or code. Performing SFTA on the design may enable application of SFTA to critical code only, thus reducing the amount of effort. We attempt to develop a relationship between UML/spl trade/ design diagrams and fault tree symbology to enable adaptation of a commercial FTA tool to at least one software design language. Such a result would reduce the amount of fault tree effort both for size (design instead of code) and for manual effort.
{"title":"Fault tree analysis for software design","authors":"Massood Towhidnejad, D. Wallace, A. Gallo","doi":"10.1109/SEW.2002.1199446","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199446","url":null,"abstract":"We present a study on software fault tree analysis (SFTA) conducted at the Software Assurance Technology Center at NASA Goddard Space Flight Center. While researchers have made various attempts at SFTA, software assurance practitioners have been slow to adopt it. One reason is the intense manual effort needed to identify and draw the fault trees for the code of large software projects. Another is the lack of commercial tools to assist in the technique for software. Most SFTA research efforts have been directed at requirements or code. Performing SFTA on the design may enable application of SFTA to critical code only, thus reducing the amount of effort. We attempt to develop a relationship between UML/spl trade/ design diagrams and fault tree symbology to enable adaptation of a commercial FTA tool to at least one software design language. Such a result would reduce the amount of fault tree effort both for size (design instead of code) and for manual effort.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"89 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131895857","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199449
T. Menzies, Justin S Di, Stefano, Mike Chapman, Ken McGill
Within NASA, there is an increasing awareness that software is of growing importance to the success of missions. Much data has been collected, and many theories have been advanced on how to reduce or eliminate errors in code. However, learning requires experience. We document a new NASA initiative to build a centralized repository of software defect data; in particular, we document one specific case study on software metrics. Software metrics are used as a basis for prediction of errors in code modules, but there are many different metrics available. McCabe is one of the more popular tools used to produce metrics, but, other metrics can be more significant.
{"title":"Metrics that matter","authors":"T. Menzies, Justin S Di, Stefano, Mike Chapman, Ken McGill","doi":"10.1109/SEW.2002.1199449","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199449","url":null,"abstract":"Within NASA, there is an increasing awareness that software is of growing importance to the success of missions. Much data has been collected, and many theories have been advanced on how to reduce or eliminate errors in code. However, learning requires experience. We document a new NASA initiative to build a centralized repository of software defect data; in particular, we document one specific case study on software metrics. Software metrics are used as a basis for prediction of errors in code modules, but there are many different metrics available. McCabe is one of the more popular tools used to produce metrics, but, other metrics can be more significant.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125199597","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199462
J. D. Hicks, R. A. Flanagan, P. Petrov, A. Stoyen
The battlefield is a place of violence, chaos and ruled by uncertainty. Timely knowledge of what's happening around a soldier can mean the difference between life and death. The goals of an enhanced mobile infantry as expressed in Heinlein's timeless Starship Troopers is becoming a reality today through innovative progress being made by the U.S. Army's 21st Century Land Warrior (LW) program. However, the current system does not provide a "head up" display like the capability that today's avionics provides to fighter pilots. What is wanted is that when the soldier employs the weapon he sees objects easily distinguishable as friendly or not, as well as enemy locations. This work is aimed at developing smart icons that are superimposed on the video from a LW weapon sight. Eyekon is an intelligent agent-based decision support system hosted on the LW's wearable computer. Eyekon will use LW networked position reports to provide a perspective view in the weapon sight. This will naturally draw the warrior to the most desirable target. There are many performance and human factors issues to address before the concept can be used in lethal situations.
{"title":"Eyekon: augmented reality for battlefield soldiers","authors":"J. D. Hicks, R. A. Flanagan, P. Petrov, A. Stoyen","doi":"10.1109/SEW.2002.1199462","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199462","url":null,"abstract":"The battlefield is a place of violence, chaos and ruled by uncertainty. Timely knowledge of what's happening around a soldier can mean the difference between life and death. The goals of an enhanced mobile infantry as expressed in Heinlein's timeless Starship Troopers is becoming a reality today through innovative progress being made by the U.S. Army's 21st Century Land Warrior (LW) program. However, the current system does not provide a \"head up\" display like the capability that today's avionics provides to fighter pilots. What is wanted is that when the soldier employs the weapon he sees objects easily distinguishable as friendly or not, as well as enemy locations. This work is aimed at developing smart icons that are superimposed on the video from a LW weapon sight. Eyekon is an intelligent agent-based decision support system hosted on the LW's wearable computer. Eyekon will use LW networked position reports to provide a perspective view in the weapon sight. This will naturally draw the warrior to the most desirable target. There are many performance and human factors issues to address before the concept can be used in lethal situations.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"88 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117279995","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 : 2002-12-05DOI: 10.1109/SEW.2002.1199461
Marcus Brohede, S. F. Andler
We present a communication architecture that uses a distributed active real-time database system as its communication medium. The proposed architecture incorporates a database as the shared "whiteboard" through which every participating node may communicate by writing and reading data. This approach is useful in complex sharing applications such as distributed real-time simulations. The architecture deals with performance problems inherited from databases and distribution by using eventual consistency to increase predictability and availability of local data access. As a filtering mechanism, active functionality is used to control complexity. This whiteboard communication architecture is suitable for distributed real-time simulations, and a single-node prototype implementation of such a database in conjunction with the distributed simulation standard high level architecture (HLA) has shown encouraging results. The prototype is being extended to multinode simulation to gain additional experience before the communication architecture is deployed to actual systems.
{"title":"Distributed simulation communication through an active real-time database","authors":"Marcus Brohede, S. F. Andler","doi":"10.1109/SEW.2002.1199461","DOIUrl":"https://doi.org/10.1109/SEW.2002.1199461","url":null,"abstract":"We present a communication architecture that uses a distributed active real-time database system as its communication medium. The proposed architecture incorporates a database as the shared \"whiteboard\" through which every participating node may communicate by writing and reading data. This approach is useful in complex sharing applications such as distributed real-time simulations. The architecture deals with performance problems inherited from databases and distribution by using eventual consistency to increase predictability and availability of local data access. As a filtering mechanism, active functionality is used to control complexity. This whiteboard communication architecture is suitable for distributed real-time simulations, and a single-node prototype implementation of such a database in conjunction with the distributed simulation standard high level architecture (HLA) has shown encouraging results. The prototype is being extended to multinode simulation to gain additional experience before the communication architecture is deployed to actual systems.","PeriodicalId":146269,"journal":{"name":"27th Annual NASA Goddard/IEEE Software Engineering Workshop, 2002. Proceedings.","volume":"14 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2002-12-05","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116244462","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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