Symbol portrayal is an important function of GIS. Sharing symbolic information in different GIS platforms is necessary for GIS applications and users. This paper discusses the necessity, possibility and solution techn...Symbol portrayal is an important function of GIS. Sharing symbolic information in different GIS platforms is necessary for GIS applications and users. This paper discusses the necessity, possibility and solution technique of sharing a symbol library in different GIS platforms. The route map is designed as follows： first, to set up a general data model for the symbol library, then to design a standard exchange format, and finally to call on the GIS manufacturer to provide the interchange tools for their symbol library for the standard exchange format. This paper analyzes the general characteristics of GIS symbolic library, gives a symbol library model and a draft of XML schema of the symbol library exchange format.展开更多
A typical building project has a long life in the maintenance stage. Also, the cost at this stage is enormously huge compared to planning, design and construction phases. In the earlier stage, which is planning or des...A typical building project has a long life in the maintenance stage. Also, the cost at this stage is enormously huge compared to planning, design and construction phases. In the earlier stage, which is planning or design phase, however, many project participants put little emphasis on the maintenance information. As a result, important maintenance data is missing and erroneously feedback to the 3D/BIM model. This research provides a generic process model for maintenance information management for building facilities. The authors have identified that there exist most-frequently used information areas: checking information, material information, equipment information, supplier information, and maintenance history information. Each information area should be embedded in the BIM model in order to effectively feedback to the operation and maintenance stage in the project. Thus, the study has proposed a novel data format structure which can effectively link the 3D/BIM object with the maintenance data. The demonstration project shows how the data format structure is used. The contribution of this study is to provide guidance to a project practitioner by step-by-step approach in dealing with the significant maintenance information in the earlier stage of the construction project.展开更多
In the course of network supported collaborative design,the data processing plays a very vital role.Much effort has been spent in this area,and many kinds of approaches have been proposed.Based on the correlative mate...In the course of network supported collaborative design,the data processing plays a very vital role.Much effort has been spent in this area,and many kinds of approaches have been proposed.Based on the correlative materials,this paper presents extensible markup language(XML)based strategy for several important problems of data processing in network supported collaborative design,such as the representation of standard for the exchange of product model data(STEP)with XML in the product information expression and the management of XML documents using relational database.The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language(SQL)queries.Finally,the structure of data processing system based on XML is presented.展开更多
Classification of edge-on galaxies is important to astronomical studies due to our Milky Way galaxy being an edge-on galaxy.Edge-on galaxies pose a problem to classification due to their less overall brightness levels...Classification of edge-on galaxies is important to astronomical studies due to our Milky Way galaxy being an edge-on galaxy.Edge-on galaxies pose a problem to classification due to their less overall brightness levels and smaller numbers of pixels.In the current work,a novel technique for the classification of edge-on galaxies has been developed.This technique is based on the mathematical treatment of galaxy brightness data from their images.A special treatment for galaxies’brightness data is developed to enhance faint galaxies and eliminate adverse effects of high brightness backgrounds as well as adverse effects of background bright stars.A novel slimness weighting factor is developed to classify edge-on galaxies based on their slimness.The technique has the capacity to be optimized for different catalogs with different brightness levels.In the current work,the developed technique is optimized for the EFIGI catalog and is trained using a set of 1800 galaxies from this catalog.Upon classification of the full set of 4458 galaxies from the EFIGI catalog,an accuracy of 97.5% has been achieved,with an average processing time of about 0.26 seconds per galaxy on an average laptop.展开更多
基金Supported by the Spatial Information Engineering Key Laboratory Found of Chinese National Surveying and Mapping Bureau.(No.200722)
文摘Symbol portrayal is an important function of GIS. Sharing symbolic information in different GIS platforms is necessary for GIS applications and users. This paper discusses the necessity, possibility and solution technique of sharing a symbol library in different GIS platforms. The route map is designed as follows： first, to set up a general data model for the symbol library, then to design a standard exchange format, and finally to call on the GIS manufacturer to provide the interchange tools for their symbol library for the standard exchange format. This paper analyzes the general characteristics of GIS symbolic library, gives a symbol library model and a draft of XML schema of the symbol library exchange format.
文摘A typical building project has a long life in the maintenance stage. Also, the cost at this stage is enormously huge compared to planning, design and construction phases. In the earlier stage, which is planning or design phase, however, many project participants put little emphasis on the maintenance information. As a result, important maintenance data is missing and erroneously feedback to the 3D/BIM model. This research provides a generic process model for maintenance information management for building facilities. The authors have identified that there exist most-frequently used information areas: checking information, material information, equipment information, supplier information, and maintenance history information. Each information area should be embedded in the BIM model in order to effectively feedback to the operation and maintenance stage in the project. Thus, the study has proposed a novel data format structure which can effectively link the 3D/BIM object with the maintenance data. The demonstration project shows how the data format structure is used. The contribution of this study is to provide guidance to a project practitioner by step-by-step approach in dealing with the significant maintenance information in the earlier stage of the construction project.
基金supported by National High Technology Research and Development Program of China(863 Program)(No.AA420060)
文摘In the course of network supported collaborative design,the data processing plays a very vital role.Much effort has been spent in this area,and many kinds of approaches have been proposed.Based on the correlative materials,this paper presents extensible markup language(XML)based strategy for several important problems of data processing in network supported collaborative design,such as the representation of standard for the exchange of product model data(STEP)with XML in the product information expression and the management of XML documents using relational database.The paper gives a detailed exposition on how to clarify the mapping between XML structure and the relationship database structure and how XML-QL queries can be translated into structured query language(SQL)queries.Finally,the structure of data processing system based on XML is presented.
文摘Classification of edge-on galaxies is important to astronomical studies due to our Milky Way galaxy being an edge-on galaxy.Edge-on galaxies pose a problem to classification due to their less overall brightness levels and smaller numbers of pixels.In the current work,a novel technique for the classification of edge-on galaxies has been developed.This technique is based on the mathematical treatment of galaxy brightness data from their images.A special treatment for galaxies’brightness data is developed to enhance faint galaxies and eliminate adverse effects of high brightness backgrounds as well as adverse effects of background bright stars.A novel slimness weighting factor is developed to classify edge-on galaxies based on their slimness.The technique has the capacity to be optimized for different catalogs with different brightness levels.In the current work,the developed technique is optimized for the EFIGI catalog and is trained using a set of 1800 galaxies from this catalog.Upon classification of the full set of 4458 galaxies from the EFIGI catalog,an accuracy of 97.5% has been achieved,with an average processing time of about 0.26 seconds per galaxy on an average laptop.
