With the construction of spatial data infi＇astructure, automated topographic map generalization becomes an indispensable component in the community of cartography and geographic information science. This paper descri...With the construction of spatial data infi＇astructure, automated topographic map generalization becomes an indispensable component in the community of cartography and geographic information science. This paper describes a topographic map generalization system recently developed by the authors. The system has the following characteristics： 1） taking advantage of three levels of automation, i.e. fully automated generalization, batch generalization, and interactive generalization, to undertake two types of processes, i.e. intelligent inference process and repetitive operation process in generalization; 2） making use of two kinds of sources for generalizing rule library, i.e. written specifications and cartographers＇ experiences, to define a six-element structure to describe the rules; 3） employing a hierarchical structure for map databases, logically and physically; 4） employing a grid indexing technique and undo/redo operation to improve database retrieval and object generalization efficiency. Two examples of topographic map generalization are given to demonstrate the system. It reveals that the system works well. In fact, this system has been used for a number of projects and it has been found that a great improvement in efficiency compared with traditional map general- ization process can be achieved.展开更多
Through analysis of cloud computing and characteristics, the paper described cloud computing infrastructure architecture. Mainly discusses cloud computing advantages in the use of the library and the use should pay at...Through analysis of cloud computing and characteristics, the paper described cloud computing infrastructure architecture. Mainly discusses cloud computing advantages in the use of the library and the use should pay attention to the problem, on this basis, we propose a cloud- based library information platform construction model to analyze the basic architecture of cloud computing, cloud-depth study calculated at the library information platform and database access patterns operating mode, and cloud computing future development and application prospects.展开更多
This study aims to analyze the quality of positioning orthophoto generated through the technique of direct georeferencing using metric digital camera system coupled to the laser system, and both systems were aided ine...This study aims to analyze the quality of positioning orthophoto generated through the technique of direct georeferencing using metric digital camera system coupled to the laser system, and both systems were aided inertial navigation platform. For this, we compared the coordinates obtained in 16 control points collected in the field with dual-frequency GNSS （global navigation satellite system） receiver with those obtained in the orthophoto, flight conducted in June 2009 on the campus of the State University of Campinas--UNICAMP, using a medium format digital camera and laser system, with which we obtained images with a spatial resolution of 0.15 m. Taking into account the pattern accuracy cartographic used in Brazil, it is concluded that the products produced have a standard accuracy ＂A＂ to 1：2,000 scale, which represents the best quality level, both for planimetric as for altimetry, and that the procedure reached results consistent with cartographic products in 1：2,000 scale, representing a reduction of steps in the mapping process, necessary for the preparation of cartographic databases with reduction of time for preparation of design basis large civil engineering projects, such as roads, railways, studies of urban road systems, power plants and other infrastructure systems needed to develop the country.展开更多
The design and implementation of an online guide system were presented for patients.The system offers a website that makes it easier for patients,or any ordinary visitor to diagnose their disease by simply uploading t...The design and implementation of an online guide system were presented for patients.The system offers a website that makes it easier for patients,or any ordinary visitor to diagnose their disease by simply uploading their MRI image,the website also assists the patient in determining the doctor they need to see,and finding the nearest hospital or blood bank.To build the website,SQL Server,MAT-LAB,and Adobe Dreamweaver were utilized.The rapid increase in digital images produced in hospitals us-ing medical imaging techniques such as X-Ray,CT scans,MRI,and ultrasound has increased the demand for efficient image retrieval systems.Personal description,and annotation of each image in a large database using text-based indexing(also known as the Metadata approach)is time-consuming,and impractical,making Content-based Image Retrieval(CBIR)a better option.CBIR system proposed returns results based on visual features of the image,such as color,texture,and shape.展开更多
基金Under the auspices of the National Natural Science Foundation of China (No. 40301037), and a PolyU Project(G-T873)
文摘With the construction of spatial data infi＇astructure, automated topographic map generalization becomes an indispensable component in the community of cartography and geographic information science. This paper describes a topographic map generalization system recently developed by the authors. The system has the following characteristics： 1） taking advantage of three levels of automation, i.e. fully automated generalization, batch generalization, and interactive generalization, to undertake two types of processes, i.e. intelligent inference process and repetitive operation process in generalization; 2） making use of two kinds of sources for generalizing rule library, i.e. written specifications and cartographers＇ experiences, to define a six-element structure to describe the rules; 3） employing a hierarchical structure for map databases, logically and physically; 4） employing a grid indexing technique and undo/redo operation to improve database retrieval and object generalization efficiency. Two examples of topographic map generalization are given to demonstrate the system. It reveals that the system works well. In fact, this system has been used for a number of projects and it has been found that a great improvement in efficiency compared with traditional map general- ization process can be achieved.
文摘Through analysis of cloud computing and characteristics, the paper described cloud computing infrastructure architecture. Mainly discusses cloud computing advantages in the use of the library and the use should pay attention to the problem, on this basis, we propose a cloud- based library information platform construction model to analyze the basic architecture of cloud computing, cloud-depth study calculated at the library information platform and database access patterns operating mode, and cloud computing future development and application prospects.
文摘This study aims to analyze the quality of positioning orthophoto generated through the technique of direct georeferencing using metric digital camera system coupled to the laser system, and both systems were aided inertial navigation platform. For this, we compared the coordinates obtained in 16 control points collected in the field with dual-frequency GNSS （global navigation satellite system） receiver with those obtained in the orthophoto, flight conducted in June 2009 on the campus of the State University of Campinas--UNICAMP, using a medium format digital camera and laser system, with which we obtained images with a spatial resolution of 0.15 m. Taking into account the pattern accuracy cartographic used in Brazil, it is concluded that the products produced have a standard accuracy ＂A＂ to 1：2,000 scale, which represents the best quality level, both for planimetric as for altimetry, and that the procedure reached results consistent with cartographic products in 1：2,000 scale, representing a reduction of steps in the mapping process, necessary for the preparation of cartographic databases with reduction of time for preparation of design basis large civil engineering projects, such as roads, railways, studies of urban road systems, power plants and other infrastructure systems needed to develop the country.
基金Supported by the Natural Science Foundation of Tianjin(21JCZDJC00340)。
文摘The design and implementation of an online guide system were presented for patients.The system offers a website that makes it easier for patients,or any ordinary visitor to diagnose their disease by simply uploading their MRI image,the website also assists the patient in determining the doctor they need to see,and finding the nearest hospital or blood bank.To build the website,SQL Server,MAT-LAB,and Adobe Dreamweaver were utilized.The rapid increase in digital images produced in hospitals us-ing medical imaging techniques such as X-Ray,CT scans,MRI,and ultrasound has increased the demand for efficient image retrieval systems.Personal description,and annotation of each image in a large database using text-based indexing(also known as the Metadata approach)is time-consuming,and impractical,making Content-based Image Retrieval(CBIR)a better option.CBIR system proposed returns results based on visual features of the image,such as color,texture,and shape.
