Contemporary distributed collaborative systems tend to utilize either a client-server or a pure peer-to-peer paradigm. A client-server solution may potentially spawn direct connections between the clients to offload the server thereby creating a hybrid architecture. A pure peer-to-peer paradigm may on the other hand fully eliminate the need for a server. However, some situations call for the strengths of both approaches without relying on either of them. A system might both be used in environments where an infrastructure is present and in environments where it is not. In this paper we present an architecture and early implementation of a system capable of adapting to its operating environment, choosing the best fit combination of the client-server and peer-to-peer architectures. The architecture creates a seamless integration between a centralized hybrid architecture and a decentralized architecture, relying on what we have termed Peer-to-peer Distributed Shared Objects (PDSO). The proposed solution has been implemented and early evaluation has begun. Furthermore, the approach has been utilized to create a real distributed collaborative system for collaboration in hospitals.
{"title":"The ABC adaptive fusion architecture","authors":"Jonathan Bunde-Pedersen, M. Mogensen, J. Bardram","doi":"10.1145/1169075.1169076","DOIUrl":"https://doi.org/10.1145/1169075.1169076","url":null,"abstract":"Contemporary distributed collaborative systems tend to utilize either a client-server or a pure peer-to-peer paradigm. A client-server solution may potentially spawn direct connections between the clients to offload the server thereby creating a hybrid architecture. A pure peer-to-peer paradigm may on the other hand fully eliminate the need for a server. However, some situations call for the strengths of both approaches without relying on either of them. A system might both be used in environments where an infrastructure is present and in environments where it is not. In this paper we present an architecture and early implementation of a system capable of adapting to its operating environment, choosing the best fit combination of the client-server and peer-to-peer architectures. The architecture creates a seamless integration between a centralized hybrid architecture and a decentralized architecture, relying on what we have termed Peer-to-peer Distributed Shared Objects (PDSO). The proposed solution has been implemented and early evaluation has begun. Furthermore, the approach has been utilized to create a real distributed collaborative system for collaboration in hospitals.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2006-11-27","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134529923","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}
S. Boumerdassi, Papa Kane Diop, É. Renault, A. Wei
Radio Frequency Identification (RFID) technology is a method to remotely store and retrieve data using a small microchip called the RFID tag. This makes identification, authentication of objects and people possible without any physical contact between a tag and its reader. First developed in 1940 by the British army, RFID have developed considerably thanks to the fast development of radio techniques during the past few years. As of today, RFID have been applied to a wide range of problems: supply chain management to replace barcode, access control in restricted areas such as laboratories and airports, asset tracking and locating medical staff or certain patients to ensure an efficient response in medical emergencies. As a result, billions of tags will be deployed within the next years. However, RFID development is threatened by privacy and security risks. The limited capabilities of RFID tags make privacy and security enforcement a special challenge. This article presents a new method to ensure a mutual authentication between tags and readers using only two messages and without the use of complex cryptography.
{"title":"A new two-message authentication protocol for RFID sensor networks","authors":"S. Boumerdassi, Papa Kane Diop, É. Renault, A. Wei","doi":"10.1145/1101480.1101493","DOIUrl":"https://doi.org/10.1145/1101480.1101493","url":null,"abstract":"Radio Frequency Identification (RFID) technology is a method to remotely store and retrieve data using a small microchip called the RFID tag. This makes identification, authentication of objects and people possible without any physical contact between a tag and its reader. First developed in 1940 by the British army, RFID have developed considerably thanks to the fast development of radio techniques during the past few years. As of today, RFID have been applied to a wide range of problems: supply chain management to replace barcode, access control in restricted areas such as laboratories and airports, asset tracking and locating medical staff or certain patients to ensure an efficient response in medical emergencies. As a result, billions of tags will be deployed within the next years. However, RFID development is threatened by privacy and security risks. The limited capabilities of RFID tags make privacy and security enforcement a special challenge. This article presents a new method to ensure a mutual authentication between tags and readers using only two messages and without the use of complex cryptography.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123048430","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}
Routing in publish/subscribe (pub/sub) features a communication model where messages are not given explicit destination addresses, but destinations are determined by matching the subscription declared by subscribers. For a dynamic computing environment with applications that have quality demands, this is not sufficient. Routing decision should, in such environments, not only depend on the subscription predicate, but should also take the quality-constraints of applications and characteristics of network paths into account. We identified three abstraction levels of these quality constraints: functional, middleware and network. The main contribution of the paper is the concept of the integration of these constraints into the pub/sub routing. This is done by extending the syntax of pub/sub system and applying four generic, proposed by us, guidelines. The added values of quality-constrained routing concept are: message delivery satisfying quality demands of applications, improvement of system scalability and more optimise use of the network resources. We discuss the use case that shows the practical value of our concept.
{"title":"Quality-constrained routing in publish/subscribe systems","authors":"B. Zieba, M. V. Sinderen, M. Wegdam","doi":"10.1145/1101480.1101481","DOIUrl":"https://doi.org/10.1145/1101480.1101481","url":null,"abstract":"Routing in publish/subscribe (pub/sub) features a communication model where messages are not given explicit destination addresses, but destinations are determined by matching the subscription declared by subscribers. For a dynamic computing environment with applications that have quality demands, this is not sufficient. Routing decision should, in such environments, not only depend on the subscription predicate, but should also take the quality-constraints of applications and characteristics of network paths into account. We identified three abstraction levels of these quality constraints: functional, middleware and network. The main contribution of the paper is the concept of the integration of these constraints into the pub/sub routing. This is done by extending the syntax of pub/sub system and applying four generic, proposed by us, guidelines. The added values of quality-constrained routing concept are: message delivery satisfying quality demands of applications, improvement of system scalability and more optimise use of the network resources. We discuss the use case that shows the practical value of our concept.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"120922526","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}
Pervasive and ad hoc computing applications are frequently deployed in dynamic networks. Due to mobility of the computing nodes, their unreliability, or a limited communication range, at any time a node may enter or leave an interaction between a group of application components. Middleware approaches have been proposed to deal with these dynamics, by supporting the dissemination (or gathering) of information in dynamic networks. In our experience however, applications frequently need to execute a complete protocol to coordinate. Existing middleware can then be used as a discovery mechanism, but offers no support for handling the protocol itself. This paper presents a middleware model that enables an easier implementation of distributed protocols that need to take into account the continuously changing context in the dynamic network. It uses roles as a first order abstraction, handles the distributed instantiation of roles in an interaction session, and maintains the session as nodes in the mobile network move. We describe our experience with applying the middleware in a case study on a system of automatic guided vehicles.
{"title":"Middleware for protocol-based coordination in dynamic networks","authors":"Kurt Schelfthout, Danny Weyns, T. Holvoet","doi":"10.1145/1101480.1101488","DOIUrl":"https://doi.org/10.1145/1101480.1101488","url":null,"abstract":"Pervasive and ad hoc computing applications are frequently deployed in dynamic networks. Due to mobility of the computing nodes, their unreliability, or a limited communication range, at any time a node may enter or leave an interaction between a group of application components. Middleware approaches have been proposed to deal with these dynamics, by supporting the dissemination (or gathering) of information in dynamic networks. In our experience however, applications frequently need to execute a complete protocol to coordinate. Existing middleware can then be used as a discovery mechanism, but offers no support for handling the protocol itself. This paper presents a middleware model that enables an easier implementation of distributed protocols that need to take into account the continuously changing context in the dynamic network. It uses roles as a first order abstraction, handles the distributed instantiation of roles in an interaction session, and maintains the session as nodes in the mobile network move. We describe our experience with applying the middleware in a case study on a system of automatic guided vehicles.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125271695","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 computing paradigm encourages the use of dynamic binding of application requirements to the resources needed to fulfill application tasks. Especially in pervasive computing that is characterized by disconnected operation and mobility, the process of using service specifications and dynamic binding becomes critical. For this, adaptation techniques that provide for seamless service composition are needed for user task execution. In this paper we present our approach to enable two kinds of adaptations: functional (due to changes in user requirements) and architectural (due to changes in nonfunctional requirements) in pervasive computing systems. The key features of our approach are to model services as workflows, service handoffs as points of variability, and context detailing for dynamic service provisioning.
{"title":"Functional and architectural adaptation in pervasive computing environments","authors":"N. Narendra, U. Bellur, S. Nandy, K. Kalapriya","doi":"10.1145/1101480.1101485","DOIUrl":"https://doi.org/10.1145/1101480.1101485","url":null,"abstract":"Service-oriented computing paradigm encourages the use of dynamic binding of application requirements to the resources needed to fulfill application tasks. Especially in pervasive computing that is characterized by disconnected operation and mobility, the process of using service specifications and dynamic binding becomes critical. For this, adaptation techniques that provide for seamless service composition are needed for user task execution. In this paper we present our approach to enable two kinds of adaptations: functional (due to changes in user requirements) and architectural (due to changes in nonfunctional requirements) in pervasive computing systems. The key features of our approach are to model services as workflows, service handoffs as points of variability, and context detailing for dynamic service provisioning.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"116216701","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}
We present WildCAT, an extensible Java framework to ease the creation of context-aware applications. WildCAT provides a simple yet powerful dynamic model to represent an application's execution context. The context information can be accessed by application programmers through two complimentary interfaces: synchronous requests (pull mode) and asynchronous notifications (push mode). Internally, WildCAT is designed as a framework supporting different levels of extensions, from the simple configuration of the default generic implementation to completely new implementations tailored to specific needs. A given application can mix different implementations for different aspects of its context while only depending on WildCAT's simple and unified API.
{"title":"WildCAT: a generic framework for context-aware applications","authors":"Pierre-Charles David, T. Ledoux","doi":"10.1145/1101480.1101483","DOIUrl":"https://doi.org/10.1145/1101480.1101483","url":null,"abstract":"We present WildCAT, an extensible Java framework to ease the creation of context-aware applications. WildCAT provides a simple yet powerful dynamic model to represent an application's execution context. The context information can be accessed by application programmers through two complimentary interfaces: synchronous requests (pull mode) and asynchronous notifications (push mode). Internally, WildCAT is designed as a framework supporting different levels of extensions, from the simple configuration of the default generic implementation to completely new implementations tailored to specific needs. A given application can mix different implementations for different aspects of its context while only depending on WildCAT's simple and unified API.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114522951","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 need for an efficient service management system in an ad-hoc network is obvious. Mobile nodes -- and with them the services they provide -- frequently enter and leave the network, imposing comparatively high dynamics that have to be considered for the design of communication protocols on nearly any network layer. In this paper we propose an ad-hoc service management system based on the Service Location Protocol (SLP) that not only allows the user to discover appropriate service providers, but also keeps him informed about the existence and the properties of alternative providers. With this information the user application is able to prepare and conduct service handovers in case of network or device failures. Moreover, it becomes possible to change to a more convenient provider when one becomes available.
{"title":"SLP-based service management for dynamic ad-hoc networks","authors":"S. Penz","doi":"10.1145/1101480.1101498","DOIUrl":"https://doi.org/10.1145/1101480.1101498","url":null,"abstract":"The need for an efficient service management system in an ad-hoc network is obvious. Mobile nodes -- and with them the services they provide -- frequently enter and leave the network, imposing comparatively high dynamics that have to be considered for the design of communication protocols on nearly any network layer. In this paper we propose an ad-hoc service management system based on the Service Location Protocol (SLP) that not only allows the user to discover appropriate service providers, but also keeps him informed about the existence and the properties of alternative providers. With this information the user application is able to prepare and conduct service handovers in case of network or device failures. Moreover, it becomes possible to change to a more convenient provider when one becomes available.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130738690","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}
Avinash Kumar, Adi Mallikarjuna V. Reddy, D. Janakiram
With the advancement of technology in micro-electronics and wireless communication, small miniature devices called sensor nodes can be used to perform various tasks by forming themselves in to wireless sensor networks. In Wireless Sensor Networks(WSN), event detection is one of the main requirements for most of the applications. An event can be a simple event or a combination of two or more simple events (Composite Event). Detecting and reporting an event desired by the application (user) inspite of stringent constraints of sensor nodes like low energy, low bandwidth, frequent failures etc., is one of the main challenges in WSN. This can be achieved with less uncertainty and masking failures by considering collaboration among sensor nodes. We propose a framework for distributed event detection using collaboration in WSN. The framework consists of two protocols that build a tree by using a communication model similar to the Publish-Subscribe paradigm. This framework is a part of Component Oriented Middleware for Sensor networks (COMiS). In COMiS framework, components are loaded as and when required based on the application semantics. If collaboration is considered, the goal of the application can be easily accomplished even in case of failures of sensors and low energy of nodes.
{"title":"Distributed collaboration for event detection in wireless sensor networks","authors":"Avinash Kumar, Adi Mallikarjuna V. Reddy, D. Janakiram","doi":"10.1145/1101480.1101491","DOIUrl":"https://doi.org/10.1145/1101480.1101491","url":null,"abstract":"With the advancement of technology in micro-electronics and wireless communication, small miniature devices called sensor nodes can be used to perform various tasks by forming themselves in to wireless sensor networks. In Wireless Sensor Networks(WSN), event detection is one of the main requirements for most of the applications. An event can be a simple event or a combination of two or more simple events (Composite Event). Detecting and reporting an event desired by the application (user) inspite of stringent constraints of sensor nodes like low energy, low bandwidth, frequent failures etc., is one of the main challenges in WSN. This can be achieved with less uncertainty and masking failures by considering collaboration among sensor nodes. We propose a framework for distributed event detection using collaboration in WSN. The framework consists of two protocols that build a tree by using a communication model similar to the Publish-Subscribe paradigm. This framework is a part of Component Oriented Middleware for Sensor networks (COMiS). In COMiS framework, components are loaded as and when required based on the application semantics. If collaboration is considered, the goal of the application can be easily accomplished even in case of failures of sensors and low energy of nodes.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115884800","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 vision of pervasive or ubiquitous computing, conceived by Mark Weiser, foresees a world where computing is embedded in every day objects. Such objects interact with each other to perform actions on behalf of the user. As one of the mains of pervasive computing is to disappear from human perception, applications embedded in electronic devices must be proactive. This indicates that they should guess the needs of the users in order to provide them with anytime, anywhere relevant information. This characteristic must be achieved by acquiring information not only about the user, but also about the environment where he/she is immersed. This kind of information can be obtained by interacting with nearby hosts, trough a variety of networking protocols. Applications can take advantage of this characteristic by performing host discovery through heterogeneous networks, possibly at the same time. However, due to memory and storage constraints, it is not reasonable to embed all of such protocols in a mobile device. Therefore, we propose a flexible mechanism for performing host discovery in pervasive environments, allowing the insertion and removal of these networking protocols whenever needed.
Mark Weiser设想的普适或无处不在的计算设想了一个计算嵌入到日常物品中的世界。这些对象相互交互以代表用户执行操作。由于普适计算的主要内容之一正在从人类的感知中消失，嵌入电子设备的应用程序必须具有前瞻性。这表明他们应该猜测用户的需求，以便随时随地为用户提供相关信息。要实现这一特性，不仅要获取有关用户的信息，还要获取有关用户所处环境的信息。这种信息可以通过与附近的主机交互，通过各种网络协议获得。应用程序可以通过异构网络(可能同时)执行主机发现来利用这一特性。然而，由于内存和存储的限制，在移动设备中嵌入所有这些协议是不合理的。因此，我们提出了一种在普遍环境中执行主机发现的灵活机制，允许在需要时插入和删除这些网络协议。
{"title":"Improving flexibility on host discovery for pervasive computing middlewares","authors":"E. Loureiro, L. Oliveira, H. Almeida","doi":"10.1145/1101480.1101497","DOIUrl":"https://doi.org/10.1145/1101480.1101497","url":null,"abstract":"The vision of pervasive or ubiquitous computing, conceived by Mark Weiser, foresees a world where computing is embedded in every day objects. Such objects interact with each other to perform actions on behalf of the user. As one of the mains of pervasive computing is to disappear from human perception, applications embedded in electronic devices must be proactive. This indicates that they should guess the needs of the users in order to provide them with anytime, anywhere relevant information. This characteristic must be achieved by acquiring information not only about the user, but also about the environment where he/she is immersed. This kind of information can be obtained by interacting with nearby hosts, trough a variety of networking protocols. Applications can take advantage of this characteristic by performing host discovery through heterogeneous networks, possibly at the same time. However, due to memory and storage constraints, it is not reasonable to embed all of such protocols in a mobile device. Therefore, we propose a flexible mechanism for performing host discovery in pervasive environments, allowing the insertion and removal of these networking protocols whenever needed.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126388006","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}
Group management service plays a key role in wireless sensor networks (WSNs) as it provides support to high level middleware services such as object tracking, security, fault-tolerance, power management, and so on. However, the way a group is managed may vary either from service to service or according to system conditions (e.g., power level, connectivity, bandwidth). For example, the group management used by the security service may differ from one used by the fault-tolerance service. In this context, this paper presents the design and implementation (TinyOS) of a group management middleware service that may be dynamically reconfigurable. In order to illustrate how the proposed service is adopted, we present the implementation of an object tracking service that needs the reconfigurable management group.
{"title":"A reconfigurable group management middleware service for wireless sensor networks","authors":"M. Vieira, N. Rosa","doi":"10.1145/1101480.1101490","DOIUrl":"https://doi.org/10.1145/1101480.1101490","url":null,"abstract":"Group management service plays a key role in wireless sensor networks (WSNs) as it provides support to high level middleware services such as object tracking, security, fault-tolerance, power management, and so on. However, the way a group is managed may vary either from service to service or according to system conditions (e.g., power level, connectivity, bandwidth). For example, the group management used by the security service may differ from one used by the fault-tolerance service. In this context, this paper presents the design and implementation (TinyOS) of a group management middleware service that may be dynamically reconfigurable. In order to illustrate how the proposed service is adopted, we present the implementation of an object tracking service that needs the reconfigurable management group.","PeriodicalId":364168,"journal":{"name":"workshop on Middleware for Pervasive and Ad-hoc Computing","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2005-11-28","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124308945","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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