Automatic recognition and interpretation of engineering drawing plays an important role in computer aided engineering. Detecting the positional relation between entities is an important topic in this research field. I...Automatic recognition and interpretation of engineering drawing plays an important role in computer aided engineering. Detecting the positional relation between entities is an important topic in this research field. In this paper the concepts of adjacent relativity and container window of drawing entities were proposed. By means of container window, the adjacent irrelative entities can be detected quickly and effectively, which speeds up the process of adjacent relativity detection. Meanwhile, the algorithm of adjacent relativity detection was discussed.展开更多
When workflow task needs several datasets from different locations m cloud, data transfer becomes a challenge. To avoid the unnecessary data transfer, a graphical-based data placement algo- rithm for cloud workflow is...When workflow task needs several datasets from different locations m cloud, data transfer becomes a challenge. To avoid the unnecessary data transfer, a graphical-based data placement algo- rithm for cloud workflow is proposed. The algorithm uses affinity graph to group datasets while keeping a polynomial time complexity. By integrating the algorithm, the workflow engine can intelligently select locations in which the data will reside to avoid the unnecessary data transfer during the initial stage and runtime stage. Simulations show that the proposed algorithm can effectively reduce data transfer during the workflow＇ s execution.展开更多
In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method： planetary wheel method, and analyze the principle of tooling structure and pro...In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method： planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel.展开更多
There is a CAD （computer-aided design） data exchange format named SXF （scadec exchange format） in the field of Japanese public works which was developed by a consortium in 1999 to be based on the ISO 10303-202, so...There is a CAD （computer-aided design） data exchange format named SXF （scadec exchange format） in the field of Japanese public works which was developed by a consortium in 1999 to be based on the ISO 10303-202, so that the MLIT （Ministry of Land, Infi＇astructure, Transportation and Tourism） could start e-delivery （e-submit） of CAD drawings. It is one of targets for CALS/EC （continuous acquisition and lifecycle support/electric commerce） program which MLIT are promoting since 1999. Most of local governments have followed the MLIT to start e-delivery, so that SXF has become to be a standard in the public works in Japan with many problems. SXF is an exchange format and so many design companies or contractors would submit the CAD drawings with transferred format before the delivery of e-submit even if they use usually another CAD in their offices. This paper will introduce the standard of CAD exchange format SXF through the activities of Japanese public works.展开更多
To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D w...To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D working procedure drawings. First, the projection drawings of the precursory 3D process model are obtained, then the primitives are extracted and the attributed adjacency graph (AAG) is constructed. Finally, by taking the 2D working procedure drawing as the AAG, and the projection drawing as the whole AAG, the matching problem between precursory 3D process model and 2D working procedure drawings is translated into the problem of subgraph isomorphism. To raise the matching efficiency, the AAG is partitioned, and the vertexes of the graph are classified effectively using the vertex’s attributes. Experimental results show that this method is able to support exact match and the matching efficiency can meet the requirement of practical applications.展开更多
文摘Automatic recognition and interpretation of engineering drawing plays an important role in computer aided engineering. Detecting the positional relation between entities is an important topic in this research field. In this paper the concepts of adjacent relativity and container window of drawing entities were proposed. By means of container window, the adjacent irrelative entities can be detected quickly and effectively, which speeds up the process of adjacent relativity detection. Meanwhile, the algorithm of adjacent relativity detection was discussed.
基金Supported by the National Natural Science Foundation of China(No.60903137,60970132)
文摘When workflow task needs several datasets from different locations m cloud, data transfer becomes a challenge. To avoid the unnecessary data transfer, a graphical-based data placement algo- rithm for cloud workflow is proposed. The algorithm uses affinity graph to group datasets while keeping a polynomial time complexity. By integrating the algorithm, the workflow engine can intelligently select locations in which the data will reside to avoid the unnecessary data transfer during the initial stage and runtime stage. Simulations show that the proposed algorithm can effectively reduce data transfer during the workflow＇ s execution.
文摘In order to meet the rapid needs of processing square hole in mechanical equipment, the paper expounds the square hole processing method： planetary wheel method, and analyze the principle of tooling structure and process with computer graphics parameters design. The results that, as long as the appropriate parameters, using the above method not only can punch the square hole, can also be processed triangle, the five angle and hexagonal regular polygon holes. The square hole processing method can provide theoretical basis and engineering reliable reference for related engineering and technical personnel.
文摘There is a CAD （computer-aided design） data exchange format named SXF （scadec exchange format） in the field of Japanese public works which was developed by a consortium in 1999 to be based on the ISO 10303-202, so that the MLIT （Ministry of Land, Infi＇astructure, Transportation and Tourism） could start e-delivery （e-submit） of CAD drawings. It is one of targets for CALS/EC （continuous acquisition and lifecycle support/electric commerce） program which MLIT are promoting since 1999. Most of local governments have followed the MLIT to start e-delivery, so that SXF has become to be a standard in the public works in Japan with many problems. SXF is an exchange format and so many design companies or contractors would submit the CAD drawings with transferred format before the delivery of e-submit even if they use usually another CAD in their offices. This paper will introduce the standard of CAD exchange format SXF through the activities of Japanese public works.
基金supported by the National Natural Science Foundation of China (Grant No. 51075336)the National High Technology Research and Development Program of China (Grant No. 2007AA04Z137)
文摘To meet the urgent requirement of enterprises for three-dimensional (3D) process models, an approach based on subgraph isomorphism is proposed to solve the matching problem between precursory 3D process model and 2D working procedure drawings. First, the projection drawings of the precursory 3D process model are obtained, then the primitives are extracted and the attributed adjacency graph (AAG) is constructed. Finally, by taking the 2D working procedure drawing as the AAG, and the projection drawing as the whole AAG, the matching problem between precursory 3D process model and 2D working procedure drawings is translated into the problem of subgraph isomorphism. To raise the matching efficiency, the AAG is partitioned, and the vertexes of the graph are classified effectively using the vertex’s attributes. Experimental results show that this method is able to support exact match and the matching efficiency can meet the requirement of practical applications.
