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11.
Identification and adjustment on the disfigurements of original data of VISAR are probed by developing software for VISAR data reducing based on measure theory. Then the software is applied to plate impact experiment of ceramics. The disfigurements of light intensity data are identified and adjusted through Lissajou~ figures. The results indicate that VISAR data are reduced quickly and effectively by the software, and the exact free surface velocity history is obtained. 相似文献
12.
To construct data warehouse with heterogeneous, self-governing and distributed database system is a challenge. Two problems have to be solved: one is how to collect data from heterogeneous data sources by an effective method, the other is how to clear up and change the format of the data collected from data sources. The opening and the interact-operation property of Web Services is Analyzed. A Data Collection System based on Web Services, which communicates with heterogeneous data sources with SOAP and HTTP, has been designed. A Data Collector is introduced to clear up and to transform data with composition technology. The pivotal XML technology of transforming and loading up the data are discussed. 相似文献
13.
To the question that a meter is correspond with a set of lead and a sensor,this paper presents a design of data acquisition system for vehicle based on CAN bus.In this way,the combinatorial instrument is only connected by a bus unit.Author introduces the data acquisition structure chart and the CAN interface,analyzes the software by program flow chart,and shows it's application for vehicle virtual instrument.A method of calculating vehicle speed,engine rotate speed and the course of development mileage are also given. 相似文献
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SVG based on XML is a kind of language describing 2D vector graphics.It is usability and applicability to set up WebGIS.The paper puts forward a system structure of WebGIS based on SVG,which has been applied to campus electronic map system of Chongqing University.It has been proved the method is feasibility and practicability.The paper sets forth some key techniques of implement of the system in detail: coding method of organizing SVG spatial data;generation of SVG electronic map;storage of SVG spatial data and implement of client. 相似文献
16.
A developing method is given which based on object-oriented modeling techniques for management information systems.The modeling techniques,especially,from CDM to PDM conversion,make it possible that the method can be used for developing such management information systems which based on relational database.The result shows that it can raise the efficency of the system developing,improve the system tability,enhance the system maintenability. 相似文献
17.
Data warehouse is not the simply data accumulation of operational database. For exerting the function of data warehouse, the construction of data warehouse should be convenient for the data mining and business intelligent work, supply information access, analyze, and share for decision maker. The key to constructing a successful data warehouse is to fully understand the demand of end users from beginning to the end, search and storage data surround users motive closely. This paper first analyzes the data warehouse characteristic and the sort of data component, emphasizes in effective data loading methods and strategies from operational database to data warehouse, gives five sorts data loading methods. 相似文献
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The auto-measurement of incremental linear transducer by a micro-computer is described and the data of the incremental linear transducer are gained by a computer. Under the control of the computer programme, the on-line datum processing is done and the power spectrum of the data is analyzed by the computer. Thus the auto-measurement of the incremental linear transducer is realized. 相似文献
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