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A logical design method for temporal databases based on the stability constraint and the generalization semantics

INFORMATION SCIENCES 2000年第1-4期124卷 153-171页

作者： Liu, WY Song, N Yunnan Univ Dept Comp Sci Kunming 650091 Peoples R China Kunming Univ Sci & Technol Dept Met Kunming 650093 Peoples R China

Various temporal functional dependencies have already been proposed by different researches in the field. The basic idea of these dependencies is to extend the functional dependency by including a time state. It is only the reflection of static relationship among attributes. This paper presents a new dynamic dependency. We give the concept of the stability constraint and established complete axioms for stability constraints, Generalization is an important abstract semantics. In this paper, the relationship between the class and the subclass is regarded as a scheme constraint. We present the concept of the inheritance dependency and show that the inference rules for inheritance dependencies are correct and complete. In this paper, we set up a series of design methods for temporal databases based on the generalization semantics and the stability constraint. The theory of the inheritance dependency and the stability constraint provide the guarantee for the semantic unanimity of the class hierarchy. (C) 2000 Elsevier Science Inc. All rights reserved.

关键词： temporal database relational model object-oriented method inheritance dependency stability constraint

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A Logical Design method for Relational Databases Based on Generalization and Aggregation Semantics

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Journal of Computer Science & Technology 1997年第3期12卷 252-262页

作者：刘惟一姚弘 DepartmentofComputerScience YunnanUniversityKunming650091 DepartmentofComputerScience YunnanUniversi

In this paper, a series of design methods for relational databases based on generalization and aggregation sematics is set up. The relationship between a class and its subclass is considered as a scheme constraint. The concept of inheritance dependencies, which describes the multiple inheritance among schemes,is presented in the paper. It is shown that the inference rules for inheritance dependencies are sound and complete. Furthermore, a series of results about the closure of inheritance dependencies and the minimal set of inheritance dependencies, which are analogues to functional dependencies, is obtained. In order to describe the aggregation semalltics, the concept of aggregation dependencies is given. It is easy to implement these constraints under relational database management systems.

关键词： Relational database object-oriented method inheritance generalization aggregation

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Research on segmentation scale of multi-resources remote sensing data based on object-oriented

Research on segmentation scale of multi-resources remote sen...

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2nd International Conference on Mining Engineering and Metallurgical Technology (MEMT)

作者： Lian Lian Chen Jianfei Guangzhou Univ Sch Geog Sci Guangzhou 510006 Guangdong Peoples R China

To verify a method of choosing the optimal segmentation scale, the Guangzhou Higher Education Mega Center is selected as test area for surface features extraction. Buildings, roads, waters and vegetations are extracted from 4 different resolution images using different scales. It is found that the optimal segmentation scale selected based on standard deviation of the means and mean of standard deviations of image objects' brightness is almost consistent with the optimal segmentation scale selected based on actual classification. The classification accuracy is related with spatial resolution. But for specific applications, higher resolution doesn't definitely get better classification accuracy. (C) 2011 Published by Elsevier Ltd.

关键词： Remote sensing image interpretation object-oriented method segmentation scale optimal scale classification accuracy

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A component based approach for modeling and validation of an automated manufacturing system

A component based approach for modeling and validation of an...

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8th IEEE International Conference on Emerging Technologies and Factory Automation (ETFA 2001)

作者： Cavaliere, D Simonot-Lion, F Song, YQ Hembert, O ENSEM LORIA F-54516 Vandoeuvre Les Nancy France

ISBN: (纸本)0780372417

This paper presents a modeling and validation method suited to manufacturing applications. The validation technique is relevant to performance evaluation by discrete event simulation techniques (OPNET tool). We propose an object oriented approach for the modeling of these kinds of application and identify the different classes of software and hardware components required by such an application. The specification of a software tool implementing the method is based on these classes. This tool provides two specific editors: an "Expert Editor" for the specification of new classes and an "Architecture Editor" for the modeling of an information system. The "Architecture Editor" verifies that the edited model is correct (at component and architecture levels). As the simulation support is OPNET, the tool integrates an OPNET model generator. More generally this approach leeds to the specification of an UML Profile.

关键词： simulation modeling architecture description language object-oriented method UML

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Comparison of object-oriented with pixel-based classification techniques on urban classification using TM and IKONOS imagery

Comparison of object-oriented with pixel-based classificatio...

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15th International Conference on Geoinformatics

作者： Wang, Peifa Feng, Xuezhi Zhao, Shuhe Xiao, Pengfeng Xu, Chunyan Nanjing Univ Dept Geog Informat Sci Nanjing 210093 Peoples R China

ISBN: (纸本)9780819469120

During the last decades, researchers have mainly focused on improving of the pixel-based classification methods and their applications. As the image resolution improved, it can't get good classification result. In order to overcome this problem.. the object-oriented approaches are introduced. In this paper, two methods were compared on urban area. A part of Nanjing city in china was selected as study area;TM and IKONOS imagery were employed. Three pixel-based classification methods, the maximum likelihood, ISODATA (Iterative Self-Organizing Data Analysis Technique), minimum distance method, and an object-oriented technique, the nearest neighbor method, were used to classify image, and evaluate the result. For TM imagery, the accuracy assessment of the results showed that the object-oriented classification approach couldn't get better classification result comparing to the pixel-based classification method, the salt-pepper phenomena of the pixel-based classification result images were not obvious. For IKONOS imagery, classification results provided by the object-oriented classification method were better than the pixel-based classification approaches. So, for urban classification using TM imagery, the traditional classification method could be used to get classification information and an acceptable result could be acquired. But when the IKONOS imagery was used to investigate the urban class, the object-oriented method could find the expected result.

关键词： urban classification object-oriented method pixel-based technique comparison

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Research on object-oriented System Model Based on Feature

Research on Object-Oriented System Model Based on Feature

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3rd International Conference on Advanced Design and Manufacturing Engineering (ADME 2013)

作者： Li, Kewang Li, Qiang Niu, Xinghua Tianjin Univ Technol Sch Mech Engn Tianjin 300384 Peoples R China

ISBN: (纸本)9783037858431

The paper introduces that the mechanical machining system can be divided into various objects such as parts, machining processes and manufacture resources and classified by using the objected-oriented technology in the CAD/CAPP/CAM integrated systems produced from some kind parts. Using the method of shape and surface description, the parts features can also be classified in various levels. The paper also introduces the principle and method of establishing system model on the basis of summarizing and inducing interrelation among features. We have applied the method to practice and achieved better results.

关键词： object-oriented method CAD/CAPP/CAM Model

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Research and Development of Preceding-Evaluation System of Rural Drinking Water Safety Project

Research and Development of Preceding-Evaluation System of R...

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4th IFIP TC 12 Conference on Computer and Computing Technologies in Agriculture

作者： He, Lian Cheng, Jilin Yangzhou Univ Yangzhou Peoples R China

ISBN: (纸本)9783642183355

The preceding-evaluation plays a crucial role in guiding construction. Preceding-evaluation system of rural drinking water safety project includes four main contents: opportunity evaluation, necessity evaluation, feasibility evaluation and decision evaluation. Using multi-turns specialist consultation method, the paper mainly studies the decision evaluation. Modular system structure is designed according to system function analysis and target analysis. Based on system database as the basic information support, preceding-evaluation system is developed by object-oriented method. The syetem includes the functions of project information storage, project estimation, economic analysis and decision evaluation, it can provide reference for planning, design and construction management of rural drinking water safety project.

关键词： rural drinking water safety preceding-evaluation system object-oriented method decision optimization

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Design and implementation of remote sensing extraction system of rural circulation land

Design and implementation of remote sensing extraction syste...

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International Conference on Mechatronics Engineering and Computing Technology (ICMECT)

作者： Peng Cheng Wu Hua-rui Zhu Hua-ji Beijing Acad Agr & Forestry Sci Beijing Res Ctr Informat Technol Agr Beijing Peoples R China

ISBN: (纸本)9783038351153

Hollow village is a widespread phenomenon all over China nowadays. Finding out the potential utilizable land in rural region and promote the land circulation is of great significance to holding the arable land above the red line of 1.8 billion mu in China. In this study, the image characteristics of circulating land in the study area was analyzed firstly. Then the homestead and wasteland were extracted using object-oriented remote sensing information extraction technology, which include multi-scale image segmentation and establishment of extraction rules based on ENVI. After that the purpose, function and features of extracting system of rural circulating land by remote sensing were explained and the development approach of integration of remote sensing and GIS was discussed. The ENVI/IDL secondary development library platform combined with secondary development tools ArcGIS Engine was adopted. Extracting circulating land by remote sensing images, spatial analysis and mapping functions were realized in this system, using COM technology for multi-language and multi-platform hybrid programming.

关键词： circulation land remote sensing object-oriented method extracting system

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BUILDING HEIGHTS ESTIMATION USING ZY3 DATA ---A CASE STUDY OF SHANGHAI, CHINA

BUILDING HEIGHTS ESTIMATION USING ZY3 DATA ---A CASE STUDY O...

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IEEE Joint International Geoscience and Remote Sensing Symposium (IGARSS) / 35th Canadian Symposium on Remote Sensing

作者： Wang, Xiaoqin Yu, Xiameng Ling, Feilong Fuzhou Univ Key Lab Spatial Data Min & Informat Sharing Minist Educ Spatial Informat Res Ctr Fujian Prov Fuzhou 350002 Peoples R China

ISBN: (纸本)9781479957750

The building heights and the heights' distribution of a city are important aspects of urban remote sensing researches. Building heights are estimation from the shadow on Chinese No.3 resource satellite image (ZY3) in Pudong area of Shanghai, China The morphological building/shadow indexes (MBI and MSI) derived from remotely sensed data and object-based information extraction methods are used to classify the building and its shadow. Based on the formula derived from the relationship among the sun, the satellite and the building, building heights are calculated. The most of the calculated building heights are reliable. Absolute errors below 3m are about 67.5%, the average relative error is 3.7%, the errors below 5% are about 73.7%. The proposed method could well achieve the building extraction and building heights estimation in high-resolution images.

关键词： Terms Building height shadow object-oriented method ZY3 data

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Detecting urban vegetation from IKONOS data using an object-oriented approach

Detecting urban vegetation from IKONOS data using an object-...

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25th IEEE International Geoscience and Remote Sensing Symposium (IGARSS 2005)

作者： Zhang, XY Feng, XZ Nanjing Univ Dept Urban & Resources Sci Nanjing 210093 Peoples R China

ISBN: (纸本)0780390504

Urban vegetation plays a very important role in urban planning, environmental protecting, and sustainable development policy making. High resolution remote sensing imageries like IKONOS can provide such information economically and timely. However, the traditional classifying method based on pixel results in poor accuracy for the increased resolution causes not only in inter-class spectral variability but also intra-class spectral variability. Thus, developing a new method to extract thematic information from high resolution remotely sensed data might become one of the most challenging tasks of remote sensing within the coming years. This research proposed an object-oriented method to obtain the distribution of grass and tree in urban environment. The whole process included two steps: first, the original IKONOS data and the derived data of NDVI and VI were segmented at scale 5 and then, the objects obtained from this finer segmentation process were classified into two categories (vegetation and non-vegetation) using the feature space composed of mean NDVI, ratio near-infra, mean VI, ratio green band, and mean red band, second, the data of IKONOS, NDVI and VI within the vegetation area were segmented at scale 100, and then the objects from this lager scale segmentation were classified by the feature of Stddev red-infra into grass and tree. The result of accuracy assessment showed that the proposed method had produced distributed vegetation with over 97% overall accuracy.

关键词： urban vegetation object-oriented method IKONOS

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