Technology of movement and knowledge guidance in virtual assembly is presented The designer can move the mechanical part precisely under the movement guidance The movement guidance is implemented based on constrai...Technology of movement and knowledge guidance in virtual assembly is presented The designer can move the mechanical part precisely under the movement guidance The movement guidance is implemented based on constraint recognition and assembly degree of freedom analysis A multi hierarchy knowledge base is built to represent the assembly knowledge and information The virtual assembly system judges the requirement of the designer based on the context of design task and searches for the useful knowledge and information, which can be provided to the designer in a natural way展开更多
The requirements and features of virtual assembly movement navigator areanalyzed to help operators flexibly manipulate virtual objects, precisely locate or assemble virtualparts in virtual environment. With the degree...The requirements and features of virtual assembly movement navigator areanalyzed to help operators flexibly manipulate virtual objects, precisely locate or assemble virtualparts in virtual environment. With the degree-of-freedom analysis, the assembly constrainthierarchical model is constructed and the system's constraints are built dynamically. Thus, allobjects in virtual environment can be located reasonally by the navigator. Moreover, the assemblyconstraint recognition in the process of assembly and movement correction is also discussed.展开更多
Optimizing deployment of sensors with self-healing ability is an efficient way to solve the problems of cov-erage, connectivity and the dead nodes in WSNs. This work discusses the particular relationship between the m...Optimizing deployment of sensors with self-healing ability is an efficient way to solve the problems of cov-erage, connectivity and the dead nodes in WSNs. This work discusses the particular relationship between the monitoring range and the communication range, and proposes an optimal deployment with self-healing movement algorithm for closed or semi-closed area with irregular shape, which can not only satisfy both coverage and connectivity by using as few nodes as possible, but also compensate the failure of nodes by mobility in WSNs. We compute the maximum efficient range of several neighbor sensors based on the dif-ferent relationships between monitoring range and communication range with consideration of the complex boundary or obstacles in the region, and combine it with the Euclidean Minimum Spanning Tree (EMST) algorithm to ensure the coverage and communication of Region of Interest (ROI). Besides, we calculate the location of dead nodes by Geometry Algorithm, and move the higher priority nodes to replace them by an-other Improved Virtual Force Algorithm (IVFA). Eventually, simulation results based-on MATLAB are presented, which do show that this optimal deployment with self-healing movement algorithm can ensure the coverage and communication of an entire region by requiring the least number of nodes and effectively compensate the loss of the networks.展开更多
基金China 86 3Hi techProgram CIMSTopic (No 86 3 5 11 942 0 0 1)andProvincialNatural ScienceFoundationofZhejiang (No 6 980 2 3)
文摘Technology of movement and knowledge guidance in virtual assembly is presented The designer can move the mechanical part precisely under the movement guidance The movement guidance is implemented based on constraint recognition and assembly degree of freedom analysis A multi hierarchy knowledge base is built to represent the assembly knowledge and information The virtual assembly system judges the requirement of the designer based on the context of design task and searches for the useful knowledge and information, which can be provided to the designer in a natural way
基金China 863 Hi-tech Program CIMS Topic (No.863-511-941-001) and Provincial Natural Science Foundation of Zhejiang, China (No.60008
文摘The requirements and features of virtual assembly movement navigator areanalyzed to help operators flexibly manipulate virtual objects, precisely locate or assemble virtualparts in virtual environment. With the degree-of-freedom analysis, the assembly constrainthierarchical model is constructed and the system's constraints are built dynamically. Thus, allobjects in virtual environment can be located reasonally by the navigator. Moreover, the assemblyconstraint recognition in the process of assembly and movement correction is also discussed.
文摘Optimizing deployment of sensors with self-healing ability is an efficient way to solve the problems of cov-erage, connectivity and the dead nodes in WSNs. This work discusses the particular relationship between the monitoring range and the communication range, and proposes an optimal deployment with self-healing movement algorithm for closed or semi-closed area with irregular shape, which can not only satisfy both coverage and connectivity by using as few nodes as possible, but also compensate the failure of nodes by mobility in WSNs. We compute the maximum efficient range of several neighbor sensors based on the dif-ferent relationships between monitoring range and communication range with consideration of the complex boundary or obstacles in the region, and combine it with the Euclidean Minimum Spanning Tree (EMST) algorithm to ensure the coverage and communication of Region of Interest (ROI). Besides, we calculate the location of dead nodes by Geometry Algorithm, and move the higher priority nodes to replace them by an-other Improved Virtual Force Algorithm (IVFA). Eventually, simulation results based-on MATLAB are presented, which do show that this optimal deployment with self-healing movement algorithm can ensure the coverage and communication of an entire region by requiring the least number of nodes and effectively compensate the loss of the networks.
