Web services run in a highly dynamic environment, as a result, the QoS of which will change relatively frequently. In order to make the composite service adapt to such dynamic property of Web services, we propose a se...Web services run in a highly dynamic environment, as a result, the QoS of which will change relatively frequently. In order to make the composite service adapt to such dynamic property of Web services, we propose a self-healing approach for web service composition. Such an approach is an integration of backing up in selection and reselecting in execution. In order to make the composite service heal itself as quickly as possible and minimize the number of reselections, a way of performance prediction is proposed in this paper. On this basis, the self-healing approach is presented including framework, the triggering algorithm of the reselection and the reliability model of the service. Experiments show that the proposed solutions have better performance in supporting the self-healing Web service composition.展开更多
In recent years,with the increasingly serious traffic problems in large cities of China,transformation to polycentric urban spatial structure has been considered as an important initiative to improve the urban traffic...In recent years,with the increasingly serious traffic problems in large cities of China,transformation to polycentric urban spatial structure has been considered as an important initiative to improve the urban traffic performance.This study examines the traffic performance of the polycentric spatial structure of Harbin,and analyzes the factors influencing the traffic performance of the structure using the location reselection hypothesis theory.The results show that the polycentric spatial structure does not significantly improve Harbin’s traffic performance,and only the centers in peripheral areas indicate advantages in commuting speed and distance,to which the main reason is that the social and spatial factors reduce the importance of commuting costs,making long-distance commuting economically rational and hindering possible location reselection.It is an effective direction for the improvement of the traffic performance of polycentric spatial structure by facing up to the rationality of long-distance commuting and transportation demand,improving the location equilibrium of residential and employment resources,and constructing high-grade centers in peripheral areas in appropriate locations and with comprehensive functions.展开更多
基金supported by the National Natural Science Foundation of China under Grant No. 60773218
文摘Web services run in a highly dynamic environment, as a result, the QoS of which will change relatively frequently. In order to make the composite service adapt to such dynamic property of Web services, we propose a self-healing approach for web service composition. Such an approach is an integration of backing up in selection and reselecting in execution. In order to make the composite service heal itself as quickly as possible and minimize the number of reselections, a way of performance prediction is proposed in this paper. On this basis, the self-healing approach is presented including framework, the triggering algorithm of the reselection and the reliability model of the service. Experiments show that the proposed solutions have better performance in supporting the self-healing Web service composition.
文摘In recent years,with the increasingly serious traffic problems in large cities of China,transformation to polycentric urban spatial structure has been considered as an important initiative to improve the urban traffic performance.This study examines the traffic performance of the polycentric spatial structure of Harbin,and analyzes the factors influencing the traffic performance of the structure using the location reselection hypothesis theory.The results show that the polycentric spatial structure does not significantly improve Harbin’s traffic performance,and only the centers in peripheral areas indicate advantages in commuting speed and distance,to which the main reason is that the social and spatial factors reduce the importance of commuting costs,making long-distance commuting economically rational and hindering possible location reselection.It is an effective direction for the improvement of the traffic performance of polycentric spatial structure by facing up to the rationality of long-distance commuting and transportation demand,improving the location equilibrium of residential and employment resources,and constructing high-grade centers in peripheral areas in appropriate locations and with comprehensive functions.
