Software evolution is an essential activity that adapts existing software to changes in requirements. Localizing the impact of changes is one of the most efficient strategies for successful evolution. We exploit requirements descriptions in order to extract loosely coupled components and localize changes for evolution. We define a process of elaboration for the goal model that extracts a set of control loops from the requirements descriptions as components that constitute extensible systems. We regard control loops to be independent components that prevent the impact of a change from spreading outside them. To support the elaboration, we introduce two patterns: one to extract control loops from the goal model and another to detect possible conflicts between control loops. We experimentally evaluated our approach in two types of software development and the results demonstrate that our elaboration technique helps us to analyze the impact of changes in the source code and prevent the complexity of the code from increasing.
{"title":"A goal model elaboration for localizing changes in software evolution","authors":"Hiroyuki Nakagawa, Akihiko Ohsuga, S. Honiden","doi":"10.1109/RE.2013.6636715","DOIUrl":"https://doi.org/10.1109/RE.2013.6636715","url":null,"abstract":"Software evolution is an essential activity that adapts existing software to changes in requirements. Localizing the impact of changes is one of the most efficient strategies for successful evolution. We exploit requirements descriptions in order to extract loosely coupled components and localize changes for evolution. We define a process of elaboration for the goal model that extracts a set of control loops from the requirements descriptions as components that constitute extensible systems. We regard control loops to be independent components that prevent the impact of a change from spreading outside them. To support the elaboration, we introduce two patterns: one to extract control loops from the goal model and another to detect possible conflicts between control loops. We experimentally evaluated our approach in two types of software development and the results demonstrate that our elaboration technique helps us to analyze the impact of changes in the source code and prevent the complexity of the code from increasing.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83117698","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}
Managing the costs and risks of evolution is a challenging problem in the RE community. The challenge lies in the difficulty of analyzing and assessing the proneness to requirement changes across multiple versions, especially when the scale of requirements is large. In this paper, we define a series of metrics to characterize historic evolution information, and propose a novel method for predicting requirements that are likely to evolve in the future based on the metrics. We apply the prediction method to analyze the product updates history through a case study. The empirical results show that this method can provide a tradeoff solution that narrows down the scope of change analysis to a small set of requirements, but it still can retrieve nearly half of the future changes. The results indicate that the defined metrics are sensitive to the history of requirements evolution, and the prediction method can reach a valuable outcome for requirement engineers to balance their workload and risks.
{"title":"Learning from evolution history to predict future requirement changes","authors":"Lin Shi, Qing Wang, Mingshu Li","doi":"10.1109/RE.2013.6636713","DOIUrl":"https://doi.org/10.1109/RE.2013.6636713","url":null,"abstract":"Managing the costs and risks of evolution is a challenging problem in the RE community. The challenge lies in the difficulty of analyzing and assessing the proneness to requirement changes across multiple versions, especially when the scale of requirements is large. In this paper, we define a series of metrics to characterize historic evolution information, and propose a novel method for predicting requirements that are likely to evolve in the future based on the metrics. We apply the prediction method to analyze the product updates history through a case study. The empirical results show that this method can provide a tradeoff solution that narrows down the scope of change analysis to a small set of requirements, but it still can retrieve nearly half of the future changes. The results indicate that the defined metrics are sensitive to the history of requirements evolution, and the prediction method can reach a valuable outcome for requirement engineers to balance their workload and risks.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"77188518","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}
Effective requirements traceability supports practitioners in reaching higher project maturity and better product quality. Researchers argue that effective traceability barely happens by chance or through ad-hoc efforts and that traceability should be explicitly defined upfront. However, in a previous study we found that practitioners rarely follow explicit traceability strategies. We were interested in the reason for this discrepancy. Are practitioners able to reach effective traceability without an explicit definition? More specifically, how suitable is requirements traceability that is not strategically planned in supporting a project's development process. Our interview study involved practitioners from 17 companies. These practitioners were familiar with the development process, the existing traceability and the goals of the project they reported about. For each project, we first modeled a traceability strategy based on the gathered information. Second, we examined and modeled the applied software engineering processes of each project. Thereby, we focused on executed tasks, involved actors, and pursued goals. Finally, we analyzed the quality and suitability of a project's traceability strategy. We report common problems across the analyzed traceability strategies and their possible causes. The overall quality and mismatch of analyzed traceability suggests that an upfront-defined traceability strategy is indeed required. Furthermore, we show that the decision for or against traceability relations between artifacts requires a detailed understanding of the project's engineering process and goals; emphasizing the need for a goal-oriented procedure to assess existing and define new traceability strategies.
{"title":"An empirical study on project-specific traceability strategies","authors":"P. Rempel, Patrick Mäder, Tobias Kuschke","doi":"10.1109/RE.2013.6636719","DOIUrl":"https://doi.org/10.1109/RE.2013.6636719","url":null,"abstract":"Effective requirements traceability supports practitioners in reaching higher project maturity and better product quality. Researchers argue that effective traceability barely happens by chance or through ad-hoc efforts and that traceability should be explicitly defined upfront. However, in a previous study we found that practitioners rarely follow explicit traceability strategies. We were interested in the reason for this discrepancy. Are practitioners able to reach effective traceability without an explicit definition? More specifically, how suitable is requirements traceability that is not strategically planned in supporting a project's development process. Our interview study involved practitioners from 17 companies. These practitioners were familiar with the development process, the existing traceability and the goals of the project they reported about. For each project, we first modeled a traceability strategy based on the gathered information. Second, we examined and modeled the applied software engineering processes of each project. Thereby, we focused on executed tasks, involved actors, and pursued goals. Finally, we analyzed the quality and suitability of a project's traceability strategy. We report common problems across the analyzed traceability strategies and their possible causes. The overall quality and mismatch of analyzed traceability suggests that an upfront-defined traceability strategy is indeed required. Furthermore, we show that the decision for or against traceability relations between artifacts requires a detailed understanding of the project's engineering process and goals; emphasizing the need for a goal-oriented procedure to assess existing and define new traceability strategies.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86589804","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}
As Requirements Engineering research continues to grow into a mature and rigorous discipline, an increasing focus is placed on the need for sound evaluation techniques that compare the benefits of a new solution against existing ones. In this tool demonstration we introduce TraceLab, an instrumented environment for modeling, executing, and comparatively evaluating experimental results. While initially developed for the Software Traceability domain, TraceLab provides a framework which can be populated with experiments, datasets, and reusable components for almost any empirical software engineering domain. In this demo we present examples from the Requirements Engineering domain.
{"title":"Using tracelab to design, execute, and baseline empirical requirements engineering experiments","authors":"J. Cleland-Huang, Adam Czauderna, J. Hayes","doi":"10.1109/RE.2013.6636744","DOIUrl":"https://doi.org/10.1109/RE.2013.6636744","url":null,"abstract":"As Requirements Engineering research continues to grow into a mature and rigorous discipline, an increasing focus is placed on the need for sound evaluation techniques that compare the benefits of a new solution against existing ones. In this tool demonstration we introduce TraceLab, an instrumented environment for modeling, executing, and comparatively evaluating experimental results. While initially developed for the Software Traceability domain, TraceLab provides a framework which can be populated with experiments, datasets, and reusable components for almost any empirical software engineering domain. In this demo we present examples from the Requirements Engineering domain.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"86883637","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}
A. Muyanja, P. I. Musasizi, C. Nassimbwa, S. S. Tickodri-Togboa, Edward Kale Kayihura, Amos Ngabirano
This paper presents the requirements engineering process for the Uganda Police Force Crime Records Management System. The system was envisioned to substantially improve the performance of the crime records management function of the Uganda Police Force through strengthening the pertinent processes. The requirements engineering process involved definition of the system context and goals, requirements elicitation, analysis and specification. The process was championed by the ARMS Project, Makerere University. Following the successful requirements engineering process, the ARMS Project together with the Uganda Police Force embarked on a two year project to design, construct and deploy the envisioned Crime Records Management System at selected police sites in Uganda. The key challenges faced during the requirements engineering process, such as changes in the composition of the Uganda Police Force project team, requirements traceability, and low representation of business process owners, are also presented.
{"title":"Requirements engineering for the uganda police force crime records management system","authors":"A. Muyanja, P. I. Musasizi, C. Nassimbwa, S. S. Tickodri-Togboa, Edward Kale Kayihura, Amos Ngabirano","doi":"10.1109/RE.2013.6636734","DOIUrl":"https://doi.org/10.1109/RE.2013.6636734","url":null,"abstract":"This paper presents the requirements engineering process for the Uganda Police Force Crime Records Management System. The system was envisioned to substantially improve the performance of the crime records management function of the Uganda Police Force through strengthening the pertinent processes. The requirements engineering process involved definition of the system context and goals, requirements elicitation, analysis and specification. The process was championed by the ARMS Project, Makerere University. Following the successful requirements engineering process, the ARMS Project together with the Uganda Police Force embarked on a two year project to design, construct and deploy the envisioned Crime Records Management System at selected police sites in Uganda. The key challenges faced during the requirements engineering process, such as changes in the composition of the Uganda Police Force project team, requirements traceability, and low representation of business process owners, are also presented.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83874422","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}
Patrice Caire, Nicolas Genon, P. Heymans, D. Moody
The success of requirements engineering depends critically on effective communication between business analysts and end users, yet empirical studies show that business stakeholders understand RE notations very poorly. This paper proposes a novel approach to designing RE visual notations that actively involves naïve users in the process. We use i*, one of the most influential RE notations, to demonstrate the approach, but the same approach could be applied to any RE notation. We present the results of 5 related empirical studies that show that novices outperform experts in designing symbols that are comprehensible to novices: the differences are both statistically significant and practically meaningful. Symbols designed by novices increased semantic transparency (their ability to be spontaneously interpreted by other novices) by almost 300% compared to the existing i* notation. The results challenge the conventional wisdom about visual notation design: that it should be conducted by a small group of experts; our research suggests that it should instead be conducted by large numbers of novices. The approach is consistent with Web 2.0, in that it harnesses the collective intelligence of end users and actively involves them in the notation design process as “prosumers” rather than passive consumers. We believe this approach has the potential to radically change the way visual notations are designed in the future.
{"title":"Visual notation design 2.0: Towards user comprehensible requirements engineering notations","authors":"Patrice Caire, Nicolas Genon, P. Heymans, D. Moody","doi":"10.1109/RE.2013.6636711","DOIUrl":"https://doi.org/10.1109/RE.2013.6636711","url":null,"abstract":"The success of requirements engineering depends critically on effective communication between business analysts and end users, yet empirical studies show that business stakeholders understand RE notations very poorly. This paper proposes a novel approach to designing RE visual notations that actively involves naïve users in the process. We use i*, one of the most influential RE notations, to demonstrate the approach, but the same approach could be applied to any RE notation. We present the results of 5 related empirical studies that show that novices outperform experts in designing symbols that are comprehensible to novices: the differences are both statistically significant and practically meaningful. Symbols designed by novices increased semantic transparency (their ability to be spontaneously interpreted by other novices) by almost 300% compared to the existing i* notation. The results challenge the conventional wisdom about visual notation design: that it should be conducted by a small group of experts; our research suggests that it should instead be conducted by large numbers of novices. The approach is consistent with Web 2.0, in that it harnesses the collective intelligence of end users and actively involves them in the notation design process as “prosumers” rather than passive consumers. We believe this approach has the potential to radically change the way visual notations are designed in the future.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82464378","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}
It is widely accepted that early reviews on requirements specifications (RS) are an effective and efficient quality assurance technique. So why are they still not applied all over the software industry? In this paper we pinpoint that this is due to five major challenges: 1) Software requirements are based on flawed `upstream' requirements and reviews on RS are thus in vain. 2) The impact of sociological issues related to reviews is underestimated. 3) Important quality aspects of RS escape reviews. 4) The goal of applying reviews is not made clear and different review approaches are mixed. 5) Incremental software development poses specific challenges to applying reviews on RS. In this paper we argue that in order to solve these five challenges research on reviews must take a more holistic approach, stretching to pre-project phases and incorporating various other disciplines in order to add more value for the software industry. The paper also offers preliminary solutions to the discussed challenges and sketches open research questions of high relevance for the software industry.
{"title":"Requirements reviews revisited: Residual challenges and open research questions","authors":"Frank Salger","doi":"10.1109/RE.2013.6636725","DOIUrl":"https://doi.org/10.1109/RE.2013.6636725","url":null,"abstract":"It is widely accepted that early reviews on requirements specifications (RS) are an effective and efficient quality assurance technique. So why are they still not applied all over the software industry? In this paper we pinpoint that this is due to five major challenges: 1) Software requirements are based on flawed `upstream' requirements and reviews on RS are thus in vain. 2) The impact of sociological issues related to reviews is underestimated. 3) Important quality aspects of RS escape reviews. 4) The goal of applying reviews is not made clear and different review approaches are mixed. 5) Incremental software development poses specific challenges to applying reviews on RS. In this paper we argue that in order to solve these five challenges research on reviews must take a more holistic approach, stretching to pre-project phases and incorporating various other disciplines in order to add more value for the software industry. The paper also offers preliminary solutions to the discussed challenges and sketches open research questions of high relevance for the software industry.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73313241","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}
Model-based requirements engineering supports eliciting, specifying and analyzing the work products elaborated during the requirements engineering process by providing adequate models. However, especially the inclusion of formal models needs to be investigated further. These models represent requirements and have to be integrated with reference models that define and structure the work results and their relations. We have developed the research tool MIRA to provide an infrastructure for the tool-based evaluation of the usage of models in the field of requirements engineering. In this paper we present the research questions addressed by MIRA concerning the reference model and the formal models. We explain how MIRA supports answering these research questions.
{"title":"MIRA: A tooling-framework to experiment with model-based requirements engineering","authors":"Sabine Teufl, Dongyue Mou, D. Ratiu","doi":"10.1109/RE.2013.6636740","DOIUrl":"https://doi.org/10.1109/RE.2013.6636740","url":null,"abstract":"Model-based requirements engineering supports eliciting, specifying and analyzing the work products elaborated during the requirements engineering process by providing adequate models. However, especially the inclusion of formal models needs to be investigated further. These models represent requirements and have to be integrated with reference models that define and structure the work results and their relations. We have developed the research tool MIRA to provide an infrastructure for the tool-based evaluation of the usage of models in the field of requirements engineering. In this paper we present the research questions addressed by MIRA concerning the reference model and the formal models. We explain how MIRA supports answering these research questions.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"76620367","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}
Since 2003, an award has been presented annually at the IEEE International Requirements Engineering Conference for the Most Influential Paper presented at the conference 10 years previously. In 2013, we celebrate 21 years of the Requirements Engineering Conference, and we use this as an opportunity to reflect on the Most Influential Papers to date. Two sessions of the 2013 conference highlight the work of previous award winners and provide the authors with the opportunity to describe the trajectory of their work over the ten years that led to the award, and to discuss its impact since.
{"title":"RE@21 spotlight: Most influential papers from the requirements engineering conference","authors":"M. Glinz, R. Wieringa","doi":"10.1109/RE.2013.6636755","DOIUrl":"https://doi.org/10.1109/RE.2013.6636755","url":null,"abstract":"Since 2003, an award has been presented annually at the IEEE International Requirements Engineering Conference for the Most Influential Paper presented at the conference 10 years previously. In 2013, we celebrate 21 years of the Requirements Engineering Conference, and we use this as an opportunity to reflect on the Most Influential Papers to date. Two sessions of the 2013 conference highlight the work of previous award winners and provide the authors with the opportunity to describe the trajectory of their work over the ten years that led to the award, and to discuss its impact since.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"81583790","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}
Companies require data from multiple sources to develop new information systems, such as social networking, e-commerce and location-based services. Systems rely on complex, multi-stakeholder data supply-chains to deliver value. These data supply-chains have complex privacy requirements: privacy policies affecting multiple stakeholders (e.g. user, developer, company, government) regulate the collection, use and sharing of data over multiple jurisdictions (e.g. California, United States, Europe). Increasingly, regulators expect companies to ensure consistency between company privacy policies and company data practices. To address this problem, we propose a methodology to map policy requirements in natural language to a formal representation in Description Logic. Using the formal representation, we reason about conflicting requirements within a single policy and among multiple policies in a data supply chain. Further, we enable tracing data flows within the supply-chain. We derive our methodology from an exploratory case study of Facebook platform policy. We demonstrate the feasibility of our approach in an evaluation involving Facebook, Zynga and AOL-Advertising policies. Our results identify three conflicts that exist between Facebook and Zynga policies, and one conflict within the AOL Advertising policy.
{"title":"Formal analysis of privacy requirements specifications for multi-tier applications","authors":"T. Breaux, Ashwini Rao","doi":"10.1109/RE.2013.6636701","DOIUrl":"https://doi.org/10.1109/RE.2013.6636701","url":null,"abstract":"Companies require data from multiple sources to develop new information systems, such as social networking, e-commerce and location-based services. Systems rely on complex, multi-stakeholder data supply-chains to deliver value. These data supply-chains have complex privacy requirements: privacy policies affecting multiple stakeholders (e.g. user, developer, company, government) regulate the collection, use and sharing of data over multiple jurisdictions (e.g. California, United States, Europe). Increasingly, regulators expect companies to ensure consistency between company privacy policies and company data practices. To address this problem, we propose a methodology to map policy requirements in natural language to a formal representation in Description Logic. Using the formal representation, we reason about conflicting requirements within a single policy and among multiple policies in a data supply chain. Further, we enable tracing data flows within the supply-chain. We derive our methodology from an exploratory case study of Facebook platform policy. We demonstrate the feasibility of our approach in an evaluation involving Facebook, Zynga and AOL-Advertising policies. Our results identify three conflicts that exist between Facebook and Zynga policies, and one conflict within the AOL Advertising policy.","PeriodicalId":6342,"journal":{"name":"2013 21st IEEE International Requirements Engineering Conference (RE)","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2013-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85537810","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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