Based on a proposed Web service-based grid architecture, a service grid middleware system called CROWN is designed in this paper. As the two kernel points of the middleware, the overlay-based distributed grid resource...Based on a proposed Web service-based grid architecture, a service grid middleware system called CROWN is designed in this paper. As the two kernel points of the middleware, the overlay-based distributed grid resource management mechanism is proposed, and the policy-based distributed access control mechanism with the capability of automatic negotiation of the access control policy and trust management and negotiation is also discussed in this paper. Experience of CROWN testbed deployment and application development shows that the middleware can support the typical scenarios such as computing-intensive applications, data-intensive applications and mass information processing applications.展开更多
Various sensors connected to the World Wide Web are used to obtain real-time hydrological observations.Thus,real-time management and utilization of such distributed in situ observations in the cyber-physical environme...Various sensors connected to the World Wide Web are used to obtain real-time hydrological observations.Thus,real-time management and utilization of such distributed in situ observations in the cyber-physical environment becomes possible.A Sensor Observation Service(SOS)chaining Web Feature Service(WFS)method is proposed to integrate geographical reference observation data collected by a hydrological Sensor Web into a virtual globe.This method hides the complexity of a series of information and service models in the Sensor Web realm to enable the integration of heterogeneous distributed hydrological data sources into a Spatial Data Infrastructure(SDI).The core components-a dynamic schema transformer and automatic information extractor-were designed and implemented.The SOS schema is matched to WFS schema that uses the schema transformer dynamically.The information extractor extracts and serves features automatically,conforming to standard SOS operations for observation retrieval and insertion.Feasibility experiments conducted on the Jinsha River tested this proposed method.Results show that the proposed approach allows the integration of SOS servers into legacy applications that have a higher degree of availability within many SDIs.However,this is accompanied with the drawback that only a limited part of the SOS functionality is available to clients.展开更多
文摘Based on a proposed Web service-based grid architecture, a service grid middleware system called CROWN is designed in this paper. As the two kernel points of the middleware, the overlay-based distributed grid resource management mechanism is proposed, and the policy-based distributed access control mechanism with the capability of automatic negotiation of the access control policy and trust management and negotiation is also discussed in this paper. Experience of CROWN testbed deployment and application development shows that the middleware can support the typical scenarios such as computing-intensive applications, data-intensive applications and mass information processing applications.
基金This work has been supported in part by the National Basic Research Program of China(973 Program)under Grant 2011CB707101by the National Natural Science Foundation of China under Grant 41023001,41171315,and 41021061+1 种基金by the program for New Century Excellent Talents in University under Grant NCET-11-0394by National High Technology Research and Development Program of China(863 Program)under Grant 2012AA121401.
文摘Various sensors connected to the World Wide Web are used to obtain real-time hydrological observations.Thus,real-time management and utilization of such distributed in situ observations in the cyber-physical environment becomes possible.A Sensor Observation Service(SOS)chaining Web Feature Service(WFS)method is proposed to integrate geographical reference observation data collected by a hydrological Sensor Web into a virtual globe.This method hides the complexity of a series of information and service models in the Sensor Web realm to enable the integration of heterogeneous distributed hydrological data sources into a Spatial Data Infrastructure(SDI).The core components-a dynamic schema transformer and automatic information extractor-were designed and implemented.The SOS schema is matched to WFS schema that uses the schema transformer dynamically.The information extractor extracts and serves features automatically,conforming to standard SOS operations for observation retrieval and insertion.Feasibility experiments conducted on the Jinsha River tested this proposed method.Results show that the proposed approach allows the integration of SOS servers into legacy applications that have a higher degree of availability within many SDIs.However,this is accompanied with the drawback that only a limited part of the SOS functionality is available to clients.
