Simone Grassi, Stephen Barrett, Francesco Sordillo
Our work addresses the issue of software adaptation in Service Oriented Architecture (SOA) environments. We aim to support a wide range of adaptations using a new formulation of Web Service (WS) model based on client driven service adaptation via ontological description of algorithms. We describe how this approach can be applied to a SOA scenario involving heterogeneous systems, and report on experimental work that demonstrates how services can be transformed in practice, using a framework approach.
{"title":"Ontology based algorithm modeling: obtaining adaptation for SOA environment","authors":"Simone Grassi, Stephen Barrett, Francesco Sordillo","doi":"10.1145/1388336.1388339","DOIUrl":"https://doi.org/10.1145/1388336.1388339","url":null,"abstract":"Our work addresses the issue of software adaptation in Service Oriented Architecture (SOA) environments. We aim to support a wide range of adaptations using a new formulation of Web Service (WS) model based on client driven service adaptation via ontological description of algorithms. We describe how this approach can be applied to a SOA scenario involving heterogeneous systems, and report on experimental work that demonstrates how services can be transformed in practice, using a framework approach.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"98 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133000418","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}
Mobile data services in combination with profluent Web services are seemingly the path breaking domain in current information systems research. In mobile Web services sphere, resource constrained mobile terminals are used as both Web services clients and providers. While service delivery and management from Mobile Host are technically feasible, the ability to provide proper quality of service (QoS) and discovery mechanisms for the huge number of services possible with Mobile Hosts is observed to be very critical. We have studied the security, scalability and discovery aspects of the mobile Web services and the analysis has identified the necessity of a mediation framework. This paper summarizes our QoS and discovery research and discusses the realization details and features of our enterprise service bus technology based integration framework for mobile Web service provisioning.
{"title":"Mobile web services mediation framework","authors":"S. Srirama, M. Jarke, W. Prinz","doi":"10.1145/1388336.1388337","DOIUrl":"https://doi.org/10.1145/1388336.1388337","url":null,"abstract":"Mobile data services in combination with profluent Web services are seemingly the path breaking domain in current information systems research. In mobile Web services sphere, resource constrained mobile terminals are used as both Web services clients and providers. While service delivery and management from Mobile Host are technically feasible, the ability to provide proper quality of service (QoS) and discovery mechanisms for the huge number of services possible with Mobile Hosts is observed to be very critical. We have studied the security, scalability and discovery aspects of the mobile Web services and the analysis has identified the necessity of a mediation framework. This paper summarizes our QoS and discovery research and discusses the realization details and features of our enterprise service bus technology based integration framework for mobile Web service provisioning.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"41 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130441827","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}
In a large variety of applications, it is increasingly important to provide application functionality in a modular way by means of (Web) services. At the same time, pre-defined applications are no longer suitable to cope with the high functional dynamics that can be found in novel e-business, e-health, and e-science applications. In contrast, dynamic application creation, i.e., applications that are assembled ad hoc by service composition and usually instantiated very few times, are more and more becoming prevalent. Form a systems point of view, large scale application environments like the Internet create scalability requirements towards distributed execution of composite (Web) services which go beyond the traditional non-distributed approach to manage composite services. The contribution of this paper is threefold. First, we present a novel approach that combines those aspects by using different technologies in a distributed environment to dynamically distribute composite service execution in situations where it is beneficial or required. Second, the approach considers semantic annotation of services to facilitate new possibilities for data and service co-ordination. Third, the approach also incorporates the interfaces needed to integrate service execution with semantic service composition planners to allow for dynamic forward failure recovery by contingency service re-planning. These concepts are currently developed on the basis of the peer-to-peer platform OSIRIS NEXT which supports dynamically distributed and decentralized execution of composite semantic services that are described based on OWL-S.
{"title":"A platform to support decentralized and dynamically distributed P2P composite OWL-S service execution","authors":"Thorsten Möller, H. Schuldt","doi":"10.1145/1388336.1388340","DOIUrl":"https://doi.org/10.1145/1388336.1388340","url":null,"abstract":"In a large variety of applications, it is increasingly important to provide application functionality in a modular way by means of (Web) services. At the same time, pre-defined applications are no longer suitable to cope with the high functional dynamics that can be found in novel e-business, e-health, and e-science applications. In contrast, dynamic application creation, i.e., applications that are assembled ad hoc by service composition and usually instantiated very few times, are more and more becoming prevalent. Form a systems point of view, large scale application environments like the Internet create scalability requirements towards distributed execution of composite (Web) services which go beyond the traditional non-distributed approach to manage composite services.\u0000 The contribution of this paper is threefold. First, we present a novel approach that combines those aspects by using different technologies in a distributed environment to dynamically distribute composite service execution in situations where it is beneficial or required. Second, the approach considers semantic annotation of services to facilitate new possibilities for data and service co-ordination. Third, the approach also incorporates the interfaces needed to integrate service execution with semantic service composition planners to allow for dynamic forward failure recovery by contingency service re-planning. These concepts are currently developed on the basis of the peer-to-peer platform OSIRIS NEXT which supports dynamically distributed and decentralized execution of composite semantic services that are described based on OWL-S.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"27 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124093212","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}
With the growing number of service advertisements in service marketplaces, there is a need for matchmakers which select and rank functionally similar services based on non-functional properties, such as QoS and reputation parameters. Current matchmakers only support predefined service description languages and predefined third-party repositories of service description documents, which both are hard-coded inside their internal structure, forcing providers to publish their services using a specific service publishing component. Therefore, current matchmakers are not able to look for existing services which are published using different service publishers. In this paper, we propose a flexible matchmaker for service discovery, selection, and ranking, taking both functional and non-functional properties of the services into account. The matchmaker provides an expressive language for the clients to define service requests, specifying involved repositories, non-functional properties and a utility function for ranking Web services. The proposed matchmaker enables clients to search inside existing UDDI and third-party repositories and match already published services, while supporting different service description languages as well as emerging languages. Independency from the service description language and the type of the third-party repository is preserved as long as very basic constraints are satisfied.
{"title":"Flexible matching and ranking of web service advertisements","authors":"N. Ahmadi, Walter Binder","doi":"10.1145/1388336.1388341","DOIUrl":"https://doi.org/10.1145/1388336.1388341","url":null,"abstract":"With the growing number of service advertisements in service marketplaces, there is a need for matchmakers which select and rank functionally similar services based on non-functional properties, such as QoS and reputation parameters. Current matchmakers only support predefined service description languages and predefined third-party repositories of service description documents, which both are hard-coded inside their internal structure, forcing providers to publish their services using a specific service publishing component. Therefore, current matchmakers are not able to look for existing services which are published using different service publishers.\u0000 In this paper, we propose a flexible matchmaker for service discovery, selection, and ranking, taking both functional and non-functional properties of the services into account. The matchmaker provides an expressive language for the clients to define service requests, specifying involved repositories, non-functional properties and a utility function for ranking Web services. The proposed matchmaker enables clients to search inside existing UDDI and third-party repositories and match already published services, while supporting different service description languages as well as emerging languages. Independency from the service description language and the type of the third-party repository is preserved as long as very basic constraints are satisfied.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"10 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-11-26","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129691137","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}
D. Fournier, Sonia Ben Mokhtar, N. Georgantas, V. Issarny
Context-awareness is a key challenge for pervasive computing, as it is a prime requirement towards delivering applications to users in a way that best matches user requirements, digital resources availability and physical conditions. However, enabling anytime, anywhere context-awareness, as targeted by pervasive computing, is further challenged by the openness of the environment, which requires making available context information in various computing environments. This then calls for the ad hoc networking of context sources and of context-aware applications, so that applications may always benefit from a context knowledge base, although it may be more or less rich, depending on the specific environment. Building upon the context management literature, and the Service-Oriented Architecture (SOA) paradigm that is a major enabler of open ad hoc networking, this paper sketches key context-aware system concepts that need be incorporated in the SOA style towards enabling context-aware services for pervasive computing.
{"title":"Towards ad hoc contextual services for pervasive computing","authors":"D. Fournier, Sonia Ben Mokhtar, N. Georgantas, V. Issarny","doi":"10.1145/1169091.1169097","DOIUrl":"https://doi.org/10.1145/1169091.1169097","url":null,"abstract":"Context-awareness is a key challenge for pervasive computing, as it is a prime requirement towards delivering applications to users in a way that best matches user requirements, digital resources availability and physical conditions. However, enabling anytime, anywhere context-awareness, as targeted by pervasive computing, is further challenged by the openness of the environment, which requires making available context information in various computing environments. This then calls for the ad hoc networking of context sources and of context-aware applications, so that applications may always benefit from a context knowledge base, although it may be more or less rich, depending on the specific environment. Building upon the context management literature, and the Service-Oriented Architecture (SOA) paradigm that is a major enabler of open ad hoc networking, this paper sketches key context-aware system concepts that need be incorporated in the SOA style towards enabling context-aware services for pervasive computing.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116865872","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}
Web services can be aggregated to create composite workflows that provide streamlined functionality for human users or other systems. Although industry standards and recent research have sought to define best practices and to improve end-to-end workflow composition, one area that has not fully been explored is the scheduling of a workflow's web service requests to actual service provisioning in a multi-tiered, multi-organisation environment. This issue is relevant to modern business scenarios where business processes within a workflow must complete within QoS-defined limits. Because these business processes are web service consumers, service requests must be mapped and scheduled across multiple web service providers, each with its own negotiated service level agreement. In this paper we provide heuristics for scheduling service requests from multiple business process workflows to web service providers such that a business value metric across all workflows is maximised. We show that a genetic search algorithm is appropriate to perform this scheduling, and through experimentation we show that our algorithm scales well up to a thousand workflows and produces better mappings than traditional approaches.
{"title":"Heuristics-based scheduling of composite web service workloads","authors":"T. Phan, Wen-Syan Li","doi":"10.1145/1169091.1169096","DOIUrl":"https://doi.org/10.1145/1169091.1169096","url":null,"abstract":"Web services can be aggregated to create composite workflows that provide streamlined functionality for human users or other systems. Although industry standards and recent research have sought to define best practices and to improve end-to-end workflow composition, one area that has not fully been explored is the scheduling of a workflow's web service requests to actual service provisioning in a multi-tiered, multi-organisation environment. This issue is relevant to modern business scenarios where business processes within a workflow must complete within QoS-defined limits. Because these business processes are web service consumers, service requests must be mapped and scheduled across multiple web service providers, each with its own negotiated service level agreement. In this paper we provide heuristics for scheduling service requests from multiple business process workflows to web service providers such that a business value metric across all workflows is maximised. We show that a genetic search algorithm is appropriate to perform this scheduling, and through experimentation we show that our algorithm scales well up to a thousand workflows and produces better mappings than traditional approaches.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"132 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134197806","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}
Service oriented architectures (SOAs) are becoming widespread solutions for realizing distributed applications. They promote a service view of the world in which functionalities exposed as services by different companies are assembled and reused in a standardized manner. Services are the core building blocks of SOAs and therefore modeling various aspects of services becomes a fundamental challenge. Among these aspects, quality-of-service (QoS) need to be addressed given the high dynamism of any SOA-based system. This paper introduces the basic steps of modeling QoS characteristics of services with the Web Service Modeling Ontology (WSMO) in order to provide a QoS-aware SOA. It discusses the current limitations of modeling QoS characteristics with WSMO and proposes a set of approaches towards a richer QoS modeling support. Each approach is analyzed in terms of complexity and the advantages and disadvantages of each approach are discussed.
面向服务的体系结构(soa)正在成为实现分布式应用程序的广泛解决方案。它们促进了对世界的服务视图，在该视图中，不同公司作为服务公开的功能以标准化的方式组装和重用。服务是soa的核心构建块，因此对服务的各个方面进行建模成为一项基本挑战。在这些方面中，考虑到任何基于soa的系统的高动态性，需要解决服务质量(QoS)问题。本文介绍了利用Web服务建模本体(Web Service modeling Ontology, WSMO)对服务的QoS特征进行建模的基本步骤，以提供一个能够感知QoS的SOA。讨论了目前使用WSMO建模QoS特性的局限性，并提出了一套实现更丰富的QoS建模支持的方法。对每种方法的复杂性进行了分析，并讨论了每种方法的优缺点。
{"title":"Modeling QoS characteristics in WSMO","authors":"I. Toma, Doug Foxvog, M. Jäger","doi":"10.1145/1169091.1169098","DOIUrl":"https://doi.org/10.1145/1169091.1169098","url":null,"abstract":"Service oriented architectures (SOAs) are becoming widespread solutions for realizing distributed applications. They promote a service view of the world in which functionalities exposed as services by different companies are assembled and reused in a standardized manner. Services are the core building blocks of SOAs and therefore modeling various aspects of services becomes a fundamental challenge. Among these aspects, quality-of-service (QoS) need to be addressed given the high dynamism of any SOA-based system. This paper introduces the basic steps of modeling QoS characteristics of services with the Web Service Modeling Ontology (WSMO) in order to provide a QoS-aware SOA. It discusses the current limitations of modeling QoS characteristics with WSMO and proposes a set of approaches towards a richer QoS modeling support. Each approach is analyzed in terms of complexity and the advantages and disadvantages of each approach are discussed.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"24 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"117192872","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}
Self-Healing is an emerging exigence for Information Systems where processes are more and more complicated and where many autonomous actors are involved. Self-healing mechanisms can be viewed as a set of automatic recovery actions fired at run-time according to the detected fault. These actions can be at infrastructure level (i.e., transparentl to the process), or they can be defined in the workflow model and executed by the workflow engine. Standard recovery mechanisms provided by Ws-BPEL are not enough to implement with reasonable effort lots of suitable recovery actions. The aim of this paper is to present a Self-Healing plug-in for a Ws-BPEL engine that enhances the ability of a standard engine to provide process-based recovery actions.
{"title":"SH-BPEL: a self-healing plug-in for Ws-BPEL engines","authors":"S. Modafferi, E. Mussi, B. Pernici","doi":"10.1145/1169091.1169099","DOIUrl":"https://doi.org/10.1145/1169091.1169099","url":null,"abstract":"Self-Healing is an emerging exigence for Information Systems where processes are more and more complicated and where many autonomous actors are involved. Self-healing mechanisms can be viewed as a set of automatic recovery actions fired at run-time according to the detected fault. These actions can be at infrastructure level (i.e., transparentl to the process), or they can be defined in the workflow model and executed by the workflow engine. Standard recovery mechanisms provided by Ws-BPEL are not enough to implement with reasonable effort lots of suitable recovery actions. The aim of this paper is to present a Self-Healing plug-in for a Ws-BPEL engine that enhances the ability of a standard engine to provide process-based recovery actions.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"42 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126121983","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}
Replication is a well-known technique to enhance dependability and performance in distributed systems. A plethora of replication middleware for distributed object systems has been proposed in the past decade. However, replication in service-oriented systems is still in its infancy. In this paper, we analyze some of the proposed service replication middleware solutions and compare them on an architectural level with object replication middleware. In particular, we focus on replication middleware that allows for (but is not limited to) strict consistency of replicas since this is required by many real-life applications. We identify six major infrastructure components and present a generalized architecture for both distributed object and service-oriented replication middleware. The result of our comparison is unambiguous: Replication middleware for service-oriented systems and distributed object systems (such as FT-CORBA) share many commonalities and only subtle differences caused by the different granularity of the replicated entity, or different transaction models.
{"title":"What service replication middleware can learn from object replication middleware","authors":"Johannes Osrael, Lorenz Froihofer, K. M. Göschka","doi":"10.1145/1169091.1169094","DOIUrl":"https://doi.org/10.1145/1169091.1169094","url":null,"abstract":"Replication is a well-known technique to enhance dependability and performance in distributed systems. A plethora of replication middleware for distributed object systems has been proposed in the past decade. However, replication in service-oriented systems is still in its infancy. In this paper, we analyze some of the proposed service replication middleware solutions and compare them on an architectural level with object replication middleware. In particular, we focus on replication middleware that allows for (but is not limited to) strict consistency of replicas since this is required by many real-life applications. We identify six major infrastructure components and present a generalized architecture for both distributed object and service-oriented replication middleware. The result of our comparison is unambiguous: Replication middleware for service-oriented systems and distributed object systems (such as FT-CORBA) share many commonalities and only subtle differences caused by the different granularity of the replicated entity, or different transaction models.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"34 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116665962","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}
The open/dynamic environment of Service-Oriented Computing requires middleware that can cope with services that are heterogeneous, and possibly unknown, unreliable or untrusted. Service-oriented middleware also needs to support both, ad-hoc and long-lived relationships between such services, and provide mechanisms for service coordination and cooperation. This needs to be achieved in a rapidly changing technical context with standards that are continually changing and evolving. This paper introduces adaptive application-specific middleware composites which are built using the ROAD framework. These composites are adaptive runtime role structures that allow services to be composed and autonomously reconfigured. In these composites, dynamic contracts control interactions between services, set non-functional requirements for those interactions, and measure the QoS of services against those requirements. These middleware composites can themselves be encapsulated as services that can be recursively composed and distributed. These composites can cope with changing requirements and performance of the services they compose. Composite roles and contracts also map naturally to business entities.
{"title":"Adaptive application-specific middleware","authors":"A. Colman, L. Pham, Jun Han, Jean-Guy Schneider","doi":"10.1145/1169091.1169092","DOIUrl":"https://doi.org/10.1145/1169091.1169092","url":null,"abstract":"The open/dynamic environment of Service-Oriented Computing requires middleware that can cope with services that are heterogeneous, and possibly unknown, unreliable or untrusted. Service-oriented middleware also needs to support both, ad-hoc and long-lived relationships between such services, and provide mechanisms for service coordination and cooperation. This needs to be achieved in a rapidly changing technical context with standards that are continually changing and evolving. This paper introduces adaptive application-specific middleware composites which are built using the ROAD framework. These composites are adaptive runtime role structures that allow services to be composed and autonomously reconfigured. In these composites, dynamic contracts control interactions between services, set non-functional requirements for those interactions, and measure the QoS of services against those requirements. These middleware composites can themselves be encapsulated as services that can be recursively composed and distributed. These composites can cope with changing requirements and performance of the services they compose. Composite roles and contracts also map naturally to business entities.","PeriodicalId":376035,"journal":{"name":"Middleware for Service Oriented Computing","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2006-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122023765","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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