Motivated by the problem of simplifying the manual operation of the composition process, we propose an approach to automatically compose available Web services to fulfill user＇s goal based on the assumption that ther...Motivated by the problem of simplifying the manual operation of the composition process, we propose an approach to automatically compose available Web services to fulfill user＇s goal based on the assumption that there are a set of alternative Web services with similar functionality and different QoS properties. A formal model （i.e. semantic links matrix, SLM for short ） is proposed to store semantic links values for the Web services with semantic relationship and QoS of Web services. The SLM provides a search place for a backward-search planning algorithm, at the same time; the QoS criteria make a rational and effective decision among a number of similar Web services. The function and some properties of the algorithm are analyzed. The approach can improve the correctness and flexibility for Web services composition and satisfy the local QoS attribute.展开更多
The isomorphism of planar kinematic chains is studied. The original methods for de- tecting isomorphism is discussed. A new matrix, the link -link path matrix, is presented to show the structures of planar kinematic c...The isomorphism of planar kinematic chains is studied. The original methods for de- tecting isomorphism is discussed. A new matrix, the link -link path matrix, is presented to show the structures of planar kinematic chains. It is simple and reliable to detect isomorphism of planar kinematic chains by using the link-link path matrix.展开更多
Among various DC/AC matrix converters,the isolated single-phase DC to three-phase AC matrix converter has attracted significant research attention due to its advantages of low loss,simple topology and modulation.PI co...Among various DC/AC matrix converters,the isolated single-phase DC to three-phase AC matrix converter has attracted significant research attention due to its advantages of low loss,simple topology and modulation.PI control is widely used in industrial manufacturing,but the increase in control target error and environmental factors will lead to decline of control system accuracy.We introduce a finite-control-set model predictive control(FCS-MPC)to predict the d-and q-axis currents in a high-frequency link matrix DC/AC converter(HFLMC)with a loosely coupled high-frequency transformer(LCHFT).The modulation and commutation modes of the HFLMC are introduced,transmission power of the HFLMC with air gap is given,and the output side compensated predictive model is also established.Design of LCHFT is given.The coupling coefficient of LCHFT under different air gap affects transmission efficiency.Finally,experiment results on a 300 W prototype verify correctness of the theoretical analysis and simulation.展开更多
基金the Specialized Research Fund for the DoctoralProgram of Higher Education of China ( 20050288015)Nanjing Universityof Science and Technology Innovation Funds
文摘Motivated by the problem of simplifying the manual operation of the composition process, we propose an approach to automatically compose available Web services to fulfill user＇s goal based on the assumption that there are a set of alternative Web services with similar functionality and different QoS properties. A formal model （i.e. semantic links matrix, SLM for short ） is proposed to store semantic links values for the Web services with semantic relationship and QoS of Web services. The SLM provides a search place for a backward-search planning algorithm, at the same time; the QoS criteria make a rational and effective decision among a number of similar Web services. The function and some properties of the algorithm are analyzed. The approach can improve the correctness and flexibility for Web services composition and satisfy the local QoS attribute.
文摘The isomorphism of planar kinematic chains is studied. The original methods for de- tecting isomorphism is discussed. A new matrix, the link -link path matrix, is presented to show the structures of planar kinematic chains. It is simple and reliable to detect isomorphism of planar kinematic chains by using the link-link path matrix.
基金supported by the National Natural Science Foundation of China(52577048).
文摘Among various DC/AC matrix converters,the isolated single-phase DC to three-phase AC matrix converter has attracted significant research attention due to its advantages of low loss,simple topology and modulation.PI control is widely used in industrial manufacturing,but the increase in control target error and environmental factors will lead to decline of control system accuracy.We introduce a finite-control-set model predictive control(FCS-MPC)to predict the d-and q-axis currents in a high-frequency link matrix DC/AC converter(HFLMC)with a loosely coupled high-frequency transformer(LCHFT).The modulation and commutation modes of the HFLMC are introduced,transmission power of the HFLMC with air gap is given,and the output side compensated predictive model is also established.Design of LCHFT is given.The coupling coefficient of LCHFT under different air gap affects transmission efficiency.Finally,experiment results on a 300 W prototype verify correctness of the theoretical analysis and simulation.
