Adaptivity and systems-of-systems (SoS) have always had a close relationship, as it is one of their defining features. Moreover, there is a clear similarity between the requirements of a SoS and those of many adaptive systems, such as autonomic and self-adaptive systems. In recent years, this kind of adaptive systems has been carefully studied; however, they often operate at a very different scale, being smaller than a typical SoS. The common nexus between both perspectives seem to be situated at the architectural level: the same adaptive techniques are recursively applied in different strata in a hierarchical composite. Therefore, the principles embodied in adaptive architectures seem to provide a good basis for the definition and description of SoS. This paper relates those principles to the corresponding structures in software evolution, and suggests to coordinate both through a pace layering strategy.
{"title":"On self-adaptation in systems-of-systems","authors":"María del Pilar Romay, C. E. Cuesta, L. F. Sanz","doi":"10.1145/2489850.2489856","DOIUrl":"https://doi.org/10.1145/2489850.2489856","url":null,"abstract":"Adaptivity and systems-of-systems (SoS) have always had a close relationship, as it is one of their defining features. Moreover, there is a clear similarity between the requirements of a SoS and those of many adaptive systems, such as autonomic and self-adaptive systems. In recent years, this kind of adaptive systems has been carefully studied; however, they often operate at a very different scale, being smaller than a typical SoS. The common nexus between both perspectives seem to be situated at the architectural level: the same adaptive techniques are recursively applied in different strata in a hierarchical composite. Therefore, the principles embodied in adaptive architectures seem to provide a good basis for the definition and description of SoS. This paper relates those principles to the corresponding structures in software evolution, and suggests to coordinate both through a pace layering strategy.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115176555","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}
E. Nakagawa, M. Gonçalves, Milena Guessi, Lucas B. R. Oliveira, F. Oquendo
Currently, software systems have become increasingly large and complex, often resulted by the integration of several operationally independent systems, resulting in a new class of systems: the Systems of Systems (SoS). In another perspective, software architectures play a major role in determining system quality, since they form the backbone of any successful software-intensive system. Attention given to the software architectures of SoS is also certainly fundamental to the success of such systems. However, it is observed that there is a lack of works that present a wide and, at the same time, a detailed panorama about how SoS architectures have been treated. In this scenario, the main contribution of this paper is to present the state of the art on software architectures of SoS, mainly regarding their development, representation, evaluation, and evolution. This work also contributes with future research topics on SoS architectures that should be still investigated. Besides that, we intend this paper opens new perspectives of research in the software architecture area, intending to contribute to the success of SoS.
{"title":"The state of the art and future perspectives in systems of systems software architectures","authors":"E. Nakagawa, M. Gonçalves, Milena Guessi, Lucas B. R. Oliveira, F. Oquendo","doi":"10.1145/2489850.2489853","DOIUrl":"https://doi.org/10.1145/2489850.2489853","url":null,"abstract":"Currently, software systems have become increasingly large and complex, often resulted by the integration of several operationally independent systems, resulting in a new class of systems: the Systems of Systems (SoS). In another perspective, software architectures play a major role in determining system quality, since they form the backbone of any successful software-intensive system. Attention given to the software architectures of SoS is also certainly fundamental to the success of such systems. However, it is observed that there is a lack of works that present a wide and, at the same time, a detailed panorama about how SoS architectures have been treated. In this scenario, the main contribution of this paper is to present the state of the art on software architectures of SoS, mainly regarding their development, representation, evaluation, and evolution. This work also contributes with future research topics on SoS architectures that should be still investigated. Besides that, we intend this paper opens new perspectives of research in the software architecture area, intending to contribute to the success of SoS.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"109 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115562979","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 system of systems (SoS) integrates independently useful systems into a larger system. Examples are integrated surveillance systems and networked smart homes. A SoS offers functions to users that cannot be provided by its individual parts, but emerge as a combination of these. However, providing these functions with a required level of quality is difficult due to inherent uncertainties, such as systems that attach and detach at will and faults that are difficult to predict. Self-adaptation is a well-studied approach that enables a system to reason about itself and adapt to achieve particular quality objectives in the face of uncertainties and change. However, the inherently decentralized nature of SoS raises fundamental challenges to self-adaptation. This paper presents three architectural styles to realize self-adaptation in SoS, discusses key challenges for each style, and outlines starting points that could help to tackle these challenges.
{"title":"On the challenges of self-adaptation in systems of systems","authors":"Danny Weyns, J. Andersson","doi":"10.1145/2489850.2489860","DOIUrl":"https://doi.org/10.1145/2489850.2489860","url":null,"abstract":"A system of systems (SoS) integrates independently useful systems into a larger system. Examples are integrated surveillance systems and networked smart homes. A SoS offers functions to users that cannot be provided by its individual parts, but emerge as a combination of these. However, providing these functions with a required level of quality is difficult due to inherent uncertainties, such as systems that attach and detach at will and faults that are difficult to predict. Self-adaptation is a well-studied approach that enables a system to reason about itself and adapt to achieve particular quality objectives in the face of uncertainties and change. However, the inherently decentralized nature of SoS raises fundamental challenges to self-adaptation. This paper presents three architectural styles to realize self-adaptation in SoS, discusses key challenges for each style, and outlines starting points that could help to tackle these challenges.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"35 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129225530","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 System-of-Systems (SoS) is a composition of components (constituent system) that are large scale and independent systems with its own purpose and operating together to achieve a common goal. This paper discusses some of the challenges for architecting SoS, considering the architecture description perspective in the light of the fundamental principles of SoS: operational and managerial independence of the components, geographic distribution, evolutionary nature and emergent behavior. The challenging topics discussed include: (i) the representation of the SoS elements; (ii) the interactions between the constituent elements; (iii) the dynamic support to enable the evolutionary nature of SoS; (iv) the need of handling quality attributes.
{"title":"Challenges for SoS architecture description","authors":"T. Batista","doi":"10.1145/2489850.2489857","DOIUrl":"https://doi.org/10.1145/2489850.2489857","url":null,"abstract":"A System-of-Systems (SoS) is a composition of components (constituent system) that are large scale and independent systems with its own purpose and operating together to achieve a common goal. This paper discusses some of the challenges for architecting SoS, considering the architecture description perspective in the light of the fundamental principles of SoS: operational and managerial independence of the components, geographic distribution, evolutionary nature and emergent behavior. The challenging topics discussed include: (i) the representation of the SoS elements; (ii) the interactions between the constituent elements; (iii) the dynamic support to enable the evolutionary nature of SoS; (iv) the need of handling quality attributes.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"2 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129880611","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}
This paper discusses how Systems of Systems (SoS) can be constructed by linking together embedded computers in constituent systems to create complex but more flexible and adaptable systems. The approach of software system development is called Federated Embedded Systems (FES) and their revolved ecosystem of players is presented, aiming to ensure quality in engineering SoS. Ecosystems for Federated Embedded Systems (EcoFES) comprise a new area of research that scales component-based software development for embedded software into new dimensions. The proposed ecosystem dimension introduces an open, flexible and adaptable SoS architecture for improving the process of FES development. In the paper, we identify some architectural challenges and discuss the implications of scaling from a closed ecosystem to an open one, providing open collaboration and innovation in the context of FES.
{"title":"Issues and challenges in ecosystems for federated embedded systems","authors":"Efi Papatheocharous, J. Axelsson, J. Andersson","doi":"10.1145/2489850.2489854","DOIUrl":"https://doi.org/10.1145/2489850.2489854","url":null,"abstract":"This paper discusses how Systems of Systems (SoS) can be constructed by linking together embedded computers in constituent systems to create complex but more flexible and adaptable systems. The approach of software system development is called Federated Embedded Systems (FES) and their revolved ecosystem of players is presented, aiming to ensure quality in engineering SoS. Ecosystems for Federated Embedded Systems (EcoFES) comprise a new area of research that scales component-based software development for embedded software into new dimensions. The proposed ecosystem dimension introduces an open, flexible and adaptable SoS architecture for improving the process of FES development. In the paper, we identify some architectural challenges and discuss the implications of scaling from a closed ecosystem to an open one, providing open collaboration and innovation in the context of FES.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"84 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131424694","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}
Jennifer Pérez, Jessica Díaz, J. Garbajosa, Agustín Yagüe, E. González, Mercedes Lopez-Perea
Smart Grids are advanced power networks that introduce intelligent management, control, and operation systems to address the new challenges generated by the growing energy demand and the appearance of renewal energies. In the literature, Smart Grids are presented as an exemplar SoS: systems composed of large heterogeneous and independent systems that leverage emergent behavior from their interaction. Smart Grids are currently scaling up the electricity service to millions of customers. These Smart Grids are known as Large-Scale Smart Grids. From the experience in several projects about Large-Scale Smart Grids, this paper defines Large-Scale Smart Grids as a SoS that integrate a set of SoS and conceptualizes the properties of this SoS. In addition, the paper defines the architectural framework for deploying the software architectures of Large-Scale Smart Grid SoS.
{"title":"Large-scale smart grids as system of systems","authors":"Jennifer Pérez, Jessica Díaz, J. Garbajosa, Agustín Yagüe, E. González, Mercedes Lopez-Perea","doi":"10.1145/2489850.2489858","DOIUrl":"https://doi.org/10.1145/2489850.2489858","url":null,"abstract":"Smart Grids are advanced power networks that introduce intelligent management, control, and operation systems to address the new challenges generated by the growing energy demand and the appearance of renewal energies. In the literature, Smart Grids are presented as an exemplar SoS: systems composed of large heterogeneous and independent systems that leverage emergent behavior from their interaction. Smart Grids are currently scaling up the electricity service to millions of customers. These Smart Grids are known as Large-Scale Smart Grids. From the experience in several projects about Large-Scale Smart Grids, this paper defines Large-Scale Smart Grids as a SoS that integrate a set of SoS and conceptualizes the properties of this SoS. In addition, the paper defines the architectural framework for deploying the software architectures of Large-Scale Smart Grid SoS.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"92 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129642406","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}
Michael Vierhauser, Rick Rabiser, P. Grünbacher, Christian Danner, Stefan Wallner
An increasing number of software systems today are systems of systems (SoS) comprising decentralized and heterogeneous systems with operational and managerial independence. The evolution of SoS is the rule and not the exception in practice due to frequently changing requirements, technologies, and markets. However, providing adequate support for the evolution of SoS is rather challenging as their behavior often emerges at runtime and is difficult to predict. Hence, SoS must be monitored during simulation and operation to ensure compliance with its requirements. In this position paper, we present challenges for SoS evolution from the domain of industrial automation. We discuss existing approaches supporting SoS evolution and derive research issues. We outline requirements for SoS evolution support and present key capabilities of a flexible monitoring and evolution infrastructure. We conclude with a discussion of research perspectives.
{"title":"Evolving systems of systems: industrial challenges and research perspectives","authors":"Michael Vierhauser, Rick Rabiser, P. Grünbacher, Christian Danner, Stefan Wallner","doi":"10.1145/2489850.2489851","DOIUrl":"https://doi.org/10.1145/2489850.2489851","url":null,"abstract":"An increasing number of software systems today are systems of systems (SoS) comprising decentralized and heterogeneous systems with operational and managerial independence. The evolution of SoS is the rule and not the exception in practice due to frequently changing requirements, technologies, and markets. However, providing adequate support for the evolution of SoS is rather challenging as their behavior often emerges at runtime and is difficult to predict. Hence, SoS must be monitored during simulation and operation to ensure compliance with its requirements. In this position paper, we present challenges for SoS evolution from the domain of industrial automation. We discuss existing approaches supporting SoS evolution and derive research issues. We outline requirements for SoS evolution support and present key capabilities of a flexible monitoring and evolution infrastructure. We conclude with a discussion of research perspectives.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"31 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116018564","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}
Flávia Coimbra Delicato, Paulo F. Pires, T. Batista, Everton Cavalcante, Bruno Costa, T. Barros
In the near future, it will be possible that every object on Earth can be identifiable and addressable. Such objects will be able to be monitored and monitor their physical environments, and of executing actions on such environments in benefit of human users. Moreover, these so-called smart objects will be endowed with wireless communication capabilities. By being uniquely addressed, wireless endowed and through the use of existing protocols and standardized formats, smart things can be integrated in the Internet and accessed as any other Web resource. In this context, the Internet of Things (IoT) emerges as a paradigm in which smart things actively collaborate among them and with other physical and virtual objects available in the Web, providing value-added information and functionalities for users. The IoT paradigm has recently showed its potential of considerably impacting the daily lives of human beings mainly due to the use and interaction of physical devices in several domains, including complex systems composed of other systems. In this paper we discuss the IoT paradigm from the perspective of Systems-of-Systems and present EcoDiF, a IoT platform that integrates heterogeneous devices to provide real-time data control, visualization, processing, and storage. In EcoDiF, devices, information, users and applications are integrated to create an IoT ecosystem in which new ideas and products can be developed in an organic way.
{"title":"Towards an IoT ecosystem","authors":"Flávia Coimbra Delicato, Paulo F. Pires, T. Batista, Everton Cavalcante, Bruno Costa, T. Barros","doi":"10.1145/2489850.2489855","DOIUrl":"https://doi.org/10.1145/2489850.2489855","url":null,"abstract":"In the near future, it will be possible that every object on Earth can be identifiable and addressable. Such objects will be able to be monitored and monitor their physical environments, and of executing actions on such environments in benefit of human users. Moreover, these so-called smart objects will be endowed with wireless communication capabilities. By being uniquely addressed, wireless endowed and through the use of existing protocols and standardized formats, smart things can be integrated in the Internet and accessed as any other Web resource. In this context, the Internet of Things (IoT) emerges as a paradigm in which smart things actively collaborate among them and with other physical and virtual objects available in the Web, providing value-added information and functionalities for users. The IoT paradigm has recently showed its potential of considerably impacting the daily lives of human beings mainly due to the use and interaction of physical devices in several domains, including complex systems composed of other systems. In this paper we discuss the IoT paradigm from the perspective of Systems-of-Systems and present EcoDiF, a IoT platform that integrates heterogeneous devices to provide real-time data control, visualization, processing, and storage. In EcoDiF, devices, information, users and applications are integrated to create an IoT ecosystem in which new ideas and products can be developed in an organic way.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125861673","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}
For the design and integration of complex systems-of-systems, various architectural decisions for recurring design problems need to be made. This requires that the software architects consider various design issues and alternatives, make trade-offs for competing requirements, and adapt the decisions to specific technologies and systems. Documentations of reusable architectural design decisions (ADDs), e.g., pattern-based decisions, provide rather informal guidelines for making recurring ADDs. These and other factors introduce many sources of uncertainty in the architectural decision making process. Existing approaches do not consider this inherent uncertainty of architectural decision making, which has been until now largely ad hoc and informal, without explicit, automated support. Apart from that, the design rationale for repeated ADDs often remains undocumented, leading to loss of architectural knowledge. To address these problems we propose to provide semi-automated support for decision making and documentation of reusable ADDs under uncertainty using a fuzzy logic expert system. We motivate our approach using a systems-of-systems example from the industry automation area in which our approach has been applied.
{"title":"Supporting architectural decision making for systems-of-systems design under uncertainty","authors":"Ioanna Lytra, Uwe Zdun","doi":"10.1145/2489850.2489859","DOIUrl":"https://doi.org/10.1145/2489850.2489859","url":null,"abstract":"For the design and integration of complex systems-of-systems, various architectural decisions for recurring design problems need to be made. This requires that the software architects consider various design issues and alternatives, make trade-offs for competing requirements, and adapt the decisions to specific technologies and systems. Documentations of reusable architectural design decisions (ADDs), e.g., pattern-based decisions, provide rather informal guidelines for making recurring ADDs. These and other factors introduce many sources of uncertainty in the architectural decision making process. Existing approaches do not consider this inherent uncertainty of architectural decision making, which has been until now largely ad hoc and informal, without explicit, automated support. Apart from that, the design rationale for repeated ADDs often remains undocumented, leading to loss of architectural knowledge. To address these problems we propose to provide semi-automated support for decision making and documentation of reusable ADDs under uncertainty using a fuzzy logic expert system. We motivate our approach using a systems-of-systems example from the industry automation area in which our approach has been applied.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"21 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124398339","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}
Wireless Sensor Networks (WSN) have large industrial applications, however the modelling is still a very complex task in view of the nature of these networks, namely because they are distributed, embedded and have strong interactions between the hardware and software parts. In addition, industrials use semi-formal methods to design their systems and validate behaviours by simulation. In this context, in order to improve the checking of the WSN properties, we propose a Model Driven Engineering (MDE) approach for modeling and checking properties like energy consumption. This approach combines the advantages of SysML and Modelica languages. It is described mainly by two steps. At first, we offer a model transformation by taking into account static, dynamic and requirement diagrams of SysML in order to specify their corresponding Modelica model. In the second step, we carried out the virtual verification of WSN energy consumption. This approach is implemented inside Topcased platform and illustrated through a cross-roads monitoring system.
{"title":"An approach combining SysML and modelica for modelling and validate wireless sensor networks","authors":"A. Hammad, H. Mountassir, Samir Chouali","doi":"10.1145/2489850.2489852","DOIUrl":"https://doi.org/10.1145/2489850.2489852","url":null,"abstract":"Wireless Sensor Networks (WSN) have large industrial applications, however the modelling is still a very complex task in view of the nature of these networks, namely because they are distributed, embedded and have strong interactions between the hardware and software parts. In addition, industrials use semi-formal methods to design their systems and validate behaviours by simulation. In this context, in order to improve the checking of the WSN properties, we propose a Model Driven Engineering (MDE) approach for modeling and checking properties like energy consumption. This approach combines the advantages of SysML and Modelica languages. It is described mainly by two steps. At first, we offer a model transformation by taking into account static, dynamic and requirement diagrams of SysML in order to specify their corresponding Modelica model. In the second step, we carried out the virtual verification of WSN energy consumption. This approach is implemented inside Topcased platform and illustrated through a cross-roads monitoring system.","PeriodicalId":281790,"journal":{"name":"International Workshop on Software Engineering for Systems-of-Systems","volume":"363 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2013-07-02","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123221342","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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