Pub Date : 2003-09-22DOI: 10.1109/ICSM.2003.1235424
D. Mall
This paper describes a case study in which the software architecture of a business application was modified to improve runtime performance. Such modifications should be performed whenever application users encounter known areas of sluggish response, long periods of maintenance, or a change in processing volume requirements. For this particular study, a framework for source code instrumentation was designed to provide convenience, data granularity, and improved control for profiling of elapsed time, operating system events, and CPU counters. The study confirms that proper selection of algorithms and data structures is essential for peak performance. Furthermore, known optimization methods, when summarized, can be used as a roadmap for tuning once hotspots are identified. Upon completion, this optimization project resulted in a speed-up factor of 18 for a typical data set.
{"title":"A case study in optimization","authors":"D. Mall","doi":"10.1109/ICSM.2003.1235424","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235424","url":null,"abstract":"This paper describes a case study in which the software architecture of a business application was modified to improve runtime performance. Such modifications should be performed whenever application users encounter known areas of sluggish response, long periods of maintenance, or a change in processing volume requirements. For this particular study, a framework for source code instrumentation was designed to provide convenience, data granularity, and improved control for profiling of elapsed time, operating system events, and CPU counters. The study confirms that proper selection of algorithms and data structures is essential for peak performance. Furthermore, known optimization methods, when summarized, can be used as a roadmap for tuning once hotspots are identified. Upon completion, this optimization project resulted in a speed-up factor of 18 for a typical data set.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123932380","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235435
J. Obbink, P. America
The system architecture of successful systems typically enjoys a long life (ten years or more). From an architecting point of view, there are two major challenges. The first challenge is to establish the "right" initial architecture that satisfies the strategic intentions, the needs and the requirements of its stakeholders and intended users. The second challenge is to nurture the architecture and keep it architecture up to date (fit and slim) with respect to the changing requirements and technologies that will occur during its lifetime. Keeping the architecture so called "evergreen" (i.e. ongoing satisfying its stakeholders needs and requirements is a very challenging architecting). The second problem is addressed in a separate paper (America et al., 2003) where we describe a method to assess and improve the ease of accommodating new requirements by system architecture once it has been established. The first problem of how to establish the initial architecture satisfying the strategic plans and intentions of its stakeholders is addressed in this presentation.
成功系统的系统架构通常具有很长的生命周期(十年或更长时间)。从架构的角度来看，有两个主要的挑战。第一个挑战是建立“正确的”初始架构，以满足其涉众和预期用户的战略意图、需求和需求。第二个挑战是培育体系结构，并使其体系结构与在其生命周期中发生的不断变化的需求和技术保持同步(适合和精简)。保持所谓的“常青”架构(即持续满足涉众的需求和需求是一个非常具有挑战性的架构)。第二个问题在另一篇论文(America et al.， 2003)中得到了解决，我们描述了一种方法，一旦系统架构建立起来，就可以评估和改进适应新需求的便利性。第一个问题是如何建立满足其利益相关者的战略计划和意图的初始架构。
{"title":"Towards evergreen architectures: on the usage of scenarios in system architecting","authors":"J. Obbink, P. America","doi":"10.1109/ICSM.2003.1235435","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235435","url":null,"abstract":"The system architecture of successful systems typically enjoys a long life (ten years or more). From an architecting point of view, there are two major challenges. The first challenge is to establish the \"right\" initial architecture that satisfies the strategic intentions, the needs and the requirements of its stakeholders and intended users. The second challenge is to nurture the architecture and keep it architecture up to date (fit and slim) with respect to the changing requirements and technologies that will occur during its lifetime. Keeping the architecture so called \"evergreen\" (i.e. ongoing satisfying its stakeholders needs and requirements is a very challenging architecting). The second problem is addressed in a separate paper (America et al., 2003) where we describe a method to assess and improve the ease of accommodating new requirements by system architecture once it has been established. The first problem of how to establish the initial architecture satisfying the strategic plans and intentions of its stakeholders is addressed in this presentation.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"121796703","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235437
Kiarash Mahdavi, M. Harman, R. Hierons
Automated software module clustering is important for maintenance of legacy systems written in a 'monolithic format' with inadequate module boundaries. Even where systems were originally designed with suitable module boundaries, structure tends to degrade as the system evolves, making re-modularization worthwhile. This paper focuses upon search-based approaches to the automated module clustering problem, where hitherto, the local search approach of hill climbing has been found to be most successful. In the paper we show that results from a set of multiple hill climbs can be combined to locate good 'building blocks' for subsequent searches. Building blocks are formed by identifying the common features in a selection of best hill climbs. This process reduces the search space, while simultaneously 'hard wiring' parts of the solution. The paper reports the results of an empirical study that show that the multiple hill climbing approach does indeed guide the search to higher peaks in subsequent executions. The paper also investigates the relationship between the improved results and the system size.
{"title":"A multiple hill climbing approach to software module clustering","authors":"Kiarash Mahdavi, M. Harman, R. Hierons","doi":"10.1109/ICSM.2003.1235437","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235437","url":null,"abstract":"Automated software module clustering is important for maintenance of legacy systems written in a 'monolithic format' with inadequate module boundaries. Even where systems were originally designed with suitable module boundaries, structure tends to degrade as the system evolves, making re-modularization worthwhile. This paper focuses upon search-based approaches to the automated module clustering problem, where hitherto, the local search approach of hill climbing has been found to be most successful. In the paper we show that results from a set of multiple hill climbs can be combined to locate good 'building blocks' for subsequent searches. Building blocks are formed by identifying the common features in a selection of best hill climbs. This process reduces the search space, while simultaneously 'hard wiring' parts of the solution. The paper reports the results of an empirical study that show that the multiple hill climbing approach does indeed guide the search to higher peaks in subsequent executions. The paper also investigates the relationship between the improved results and the system size.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"64 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128264463","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235456
A. Terekhov
Summary form only given, as follows. Software engineers sometimes have to take part in the legacy transformation projects, which are characterized by the complete absence of automated migration tools. In such cases, specialists usually aim at reproducing the original system using the new technologies, without adding any new features. It is common knowledge that it makes sense to keep the functionality as close to the original as possible, because in this case on could use the legacy system as an executable set of requirements. We argue that another, less obvious advantage of "replicating" the old system is re-use of architectural decisions that built in the original legacy system and usually represent an invaluable treasure, because they reflect an implemented understanding of the application domain.
{"title":"Re-using software architecture in legacy transformation projects","authors":"A. Terekhov","doi":"10.1109/ICSM.2003.1235456","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235456","url":null,"abstract":"Summary form only given, as follows. Software engineers sometimes have to take part in the legacy transformation projects, which are characterized by the complete absence of automated migration tools. In such cases, specialists usually aim at reproducing the original system using the new technologies, without adding any new features. It is common knowledge that it makes sense to keep the functionality as close to the original as possible, because in this case on could use the legacy system as an executable set of requirements. We argue that another, less obvious advantage of \"replicating\" the old system is re-use of architectural decisions that built in the original legacy system and usually represent an invaluable treasure, because they reflect an implemented understanding of the application domain.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128284093","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235438
Y. Limpiyakorn, I. Burnstein
Program understanding tools that are able to process large legacy systems are needed to support software engineers with maintenance tasks. One type of tool, a plan-based program understander, recognizes concepts in the code by comparing the target code against a library of programming plans. For a large plan library, an exhaustive search for a matching plan during concept recognition is not effective. This drawback limits the practical scalability of these types of tools. We propose a signature-based approach to prune the plan library. A signature in this work is a set of high level attributes derived from code features suggested by studies on human program comprehension. A SIGMA prototype is implemented to embody the proposed approach. Program plan retrieval with SIGMA (signature matching agent) shows promising results in removing irrelevant plans from consideration prior to attempting the later computational concept recognition process. It appears that the signature approach to plan retrieval may be able to facilitate the scaling up of plan-based understanders so that they can better support maintenance tasks on large legacy systems.
{"title":"Applying the signature concept to plan-based program understanding","authors":"Y. Limpiyakorn, I. Burnstein","doi":"10.1109/ICSM.2003.1235438","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235438","url":null,"abstract":"Program understanding tools that are able to process large legacy systems are needed to support software engineers with maintenance tasks. One type of tool, a plan-based program understander, recognizes concepts in the code by comparing the target code against a library of programming plans. For a large plan library, an exhaustive search for a matching plan during concept recognition is not effective. This drawback limits the practical scalability of these types of tools. We propose a signature-based approach to prune the plan library. A signature in this work is a set of high level attributes derived from code features suggested by studies on human program comprehension. A SIGMA prototype is implemented to embody the proposed approach. Program plan retrieval with SIGMA (signature matching agent) shows promising results in removing irrelevant plans from consideration prior to attempting the later computational concept recognition process. It appears that the signature approach to plan retrieval may be able to facilitate the scaling up of plan-based understanders so that they can better support maintenance tasks on large legacy systems.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"71 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130382482","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235434
K. Sartipi
This paper is a summary of the author's thesis that presents a model and an environment for recovering the high level design of legacy software systems based on user defined architectural patterns and graph matching techniques. In the proposed model, a high-level view of a software system in terms of the system components and their interactions is represented as a query, using a description language. A query is mapped onto a pattern-graph, where a component and its interactions with other components are represented as a group of graph-nodes and a group of graph-edges, respectively. Interaction constraints can be modeled by the description language as a part of the query. Such a pattern-graph is applied against an entity-relation graph that represents the information extracted from the source code of the software system. An approximate graph matching process performs a series of graph transformation operations (i.e., node/edge insertion/deletion) on the pattern-graph and uses a ranking mechanism based on data mining association to obtain a sub-optimal solution. The obtained solution corresponds to an extracted architecture that complies with the given query.
{"title":"Software architecture recovery based on pattern matching","authors":"K. Sartipi","doi":"10.1109/ICSM.2003.1235434","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235434","url":null,"abstract":"This paper is a summary of the author's thesis that presents a model and an environment for recovering the high level design of legacy software systems based on user defined architectural patterns and graph matching techniques. In the proposed model, a high-level view of a software system in terms of the system components and their interactions is represented as a query, using a description language. A query is mapped onto a pattern-graph, where a component and its interactions with other components are represented as a group of graph-nodes and a group of graph-edges, respectively. Interaction constraints can be modeled by the description language as a part of the query. Such a pattern-graph is applied against an entity-relation graph that represents the information extracted from the source code of the software system. An approximate graph matching process performs a series of graph transformation operations (i.e., node/edge insertion/deletion) on the pattern-graph and uses a ranking mechanism based on data mining association to obtain a sub-optimal solution. The obtained solution corresponds to an extracted architecture that complies with the given query.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132755936","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235449
D. Port, LiGuo Huang
Most projects commit to a set of required features and (at best) a most-likely budget and schedule for developing them. This means that, even before the changes start coming, there is roughly a 50% chance that the most-likely budget and schedule are insufficient, and the project is headed for an overrun. Planning for change in a development project is essential. But how much should be invested in architectural flexibility to accommodate this? Too little will incur a high risk of costly late changes and architecture breakage; too much may not leave enough time to implement a sufficient set of critical capabilities. We have been using and refining a model based approach to assist in determining an appropriate degree of architectural flexibility by introducing a modularity factor for the software architecture based on the core capabilities and a set of anticipated changes. This experience has helped us identify the critical success factors for strategically applying architectural flexibility within tight constraints such as cost, quality, or a fixed schedule. We elaborate the critical success factors, present a case study of their application, and their relation to recent research results in such areas as strategic design.
{"title":"Strategic architectural flexibility","authors":"D. Port, LiGuo Huang","doi":"10.1109/ICSM.2003.1235449","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235449","url":null,"abstract":"Most projects commit to a set of required features and (at best) a most-likely budget and schedule for developing them. This means that, even before the changes start coming, there is roughly a 50% chance that the most-likely budget and schedule are insufficient, and the project is headed for an overrun. Planning for change in a development project is essential. But how much should be invested in architectural flexibility to accommodate this? Too little will incur a high risk of costly late changes and architecture breakage; too much may not leave enough time to implement a sufficient set of critical capabilities. We have been using and refining a model based approach to assist in determining an appropriate degree of architectural flexibility by introducing a modularity factor for the software architecture based on the core capabilities and a set of anticipated changes. This experience has helped us identify the critical success factors for strategically applying architectural flexibility within tight constraints such as cost, quality, or a fixed schedule. We elaborate the critical success factors, present a case study of their application, and their relation to recent research results in such areas as strategic design.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"12 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115322370","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235425
K. Sartipi, K. Kontogiannis
This paper presents a graph matching model for the software architecture recovery problem. Because of their expressiveness, the graphs have been widely used for representing both the software system and its high-level view, known as the conceptual architecture. Modeling the recovery process as graph matching is an attempt to identify a sub-optimal transformation from a pattern graph, representing the high-level view of the system, onto a subgraph of the software system graph. A successful match yields a restructured system that conforms to the given pattern graph. A failed match indicates the points where the system violates specific constraints. The pattern graph generation and the incrementality of the recovery process are the important issues to be addressed. The approach is evaluated through case studies using a prototype toolkit that implements the proposed interactive recovery environment.
{"title":"On modeling software architecture recovery as graph matching","authors":"K. Sartipi, K. Kontogiannis","doi":"10.1109/ICSM.2003.1235425","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235425","url":null,"abstract":"This paper presents a graph matching model for the software architecture recovery problem. Because of their expressiveness, the graphs have been widely used for representing both the software system and its high-level view, known as the conceptual architecture. Modeling the recovery process as graph matching is an attempt to identify a sub-optimal transformation from a pattern graph, representing the high-level view of the system, onto a subgraph of the software system graph. A successful match yields a restructured system that conforms to the given pattern graph. A failed match indicates the points where the system violates specific constraints. The pattern graph generation and the incrementality of the recovery process are the important issues to be addressed. The approach is evaluated through case studies using a prototype toolkit that implements the proposed interactive recovery environment.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128370145","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235443
Akash Garg, Matt Critchlow, Ping Chen, C. V. D. Westhuizen, A. Hoek
The use of product lines is recognized as beneficial in promoting and structuring both component and architecture reuse throughout an organization. While the business practices of using product lines are well-understood and representations for specifying and capturing the underlying architecture of a product line are coming of age, support environments for managing the evolution of product line architecture are still lacking. In this paper, we present Menage, an environment specifically designed to alleviate this problem. Key features of Menage are its support for: (1) specifying variation points in product line architecture as optional and/or variant elements; (2) tracking the evolution of product line architecture and its constituent elements through explicit versioning techniques; and (3) selecting one or more product architectures out of overall product line architecture by applying user-specified criteria. In this paper, we introduce the approach underlying Menage, discuss its detailed functionality, and demonstrate its use with product line architecture for entertainment systems.
{"title":"An environment for managing evolving product line architectures","authors":"Akash Garg, Matt Critchlow, Ping Chen, C. V. D. Westhuizen, A. Hoek","doi":"10.1109/ICSM.2003.1235443","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235443","url":null,"abstract":"The use of product lines is recognized as beneficial in promoting and structuring both component and architecture reuse throughout an organization. While the business practices of using product lines are well-understood and representations for specifying and capturing the underlying architecture of a product line are coming of age, support environments for managing the evolution of product line architecture are still lacking. In this paper, we present Menage, an environment specifically designed to alleviate this problem. Key features of Menage are its support for: (1) specifying variation points in product line architecture as optional and/or variant elements; (2) tracking the evolution of product line architecture and its constituent elements through explicit versioning techniques; and (3) selecting one or more product architectures out of overall product line architecture by applying user-specified criteria. In this paper, we introduce the approach underlying Menage, discuss its detailed functionality, and demonstrate its use with product line architecture for entertainment systems.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116671695","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 : 2003-09-22DOI: 10.1109/ICSM.2003.1235419
K. Mens, Bernard Poll, Sebastián González
The conceptual structure of existing software systems is often implicit or non-existing in the source code. We propose the lightweight abstraction of intentional source-code views as a means of making these conceptual structures more explicit. Based on the experience gained with two case studies, we illustrate how intentional source-code views can simplify and improve software understanding, maintenance and evolution in various ways. We present the results as a catalog of usage scenarios in a pattern-like format.
{"title":"Using intentional source-code views to aid software maintenance","authors":"K. Mens, Bernard Poll, Sebastián González","doi":"10.1109/ICSM.2003.1235419","DOIUrl":"https://doi.org/10.1109/ICSM.2003.1235419","url":null,"abstract":"The conceptual structure of existing software systems is often implicit or non-existing in the source code. We propose the lightweight abstraction of intentional source-code views as a means of making these conceptual structures more explicit. Based on the experience gained with two case studies, we illustrate how intentional source-code views can simplify and improve software understanding, maintenance and evolution in various ways. We present the results as a catalog of usage scenarios in a pattern-like format.","PeriodicalId":141256,"journal":{"name":"International Conference on Software Maintenance, 2003. ICSM 2003. Proceedings.","volume":"33 1-2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2003-09-22","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116731107","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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