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ENTITY-ROLES MODEL AND OBJECT-ORIENTED KNOWLEDGE/DATA BASES
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作者 Pan Jiuhui Liu Zhimin Wang Yunyi(Department of Computer Science, Central South University of Technology, Changsha, 410083, China) 《Journal of Central South University》 SCIE EI CAS 1994年第1期74-77,共4页
A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is ... A Model, called 'Entity-Roles' is proposed in this paper in which the world of Interest is viewed as some mathematical structure. With respect to this structure, a First order (three-valued) Logic Language is constructured.Any world to be modelled can be logically specified in this Language. The integrity constraints on the database and the deducing rules within the Database world are derived from the proper axioms of the world being modelled. 展开更多
关键词 EXPERT systems data model object-orientATION database logic deductive QUERY
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OBJECT ORIENTED DATA MODELLING WITH APPLICATIONS TO CAD
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作者 应维云 傅向阳 周儒荣 《Transactions of Nanjing University of Aeronautics and Astronautics》 EI 1996年第2期69+63-68,共7页
An object oriented data modelling in computer aided design (CAD) databases is focused. Starting with the discussion of data modelling requirements for CAD applications, appropriate data modelling features are introdu... An object oriented data modelling in computer aided design (CAD) databases is focused. Starting with the discussion of data modelling requirements for CAD applications, appropriate data modelling features are introduced herewith. A feasible approach to select the “best” data model for an application is to analyze the data which has to be stored in the database. A data model is appropriate for modelling a given task if the information of the application environment can be easily mapped to the data model. Thus, the involved data are analyzed and then object oriented data model appropriate for CAD applications are derived. Based on the reviewed object oriented techniques applied in CAD, object oriented data modelling in CAD is addressed in details. At last 3D geometrical data models and implementation of their data model using the object oriented method are presented. 展开更多
关键词 computer aided design dataBASES data models object oriented data models complex objects geometrical models
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Scene-adaptive hierarchical data association and depth-invariant part-based appearance model for indoor multiple objects tracking 被引量:1
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作者 Hong Liu Can Wang Yuan Gao 《CAAI Transactions on Intelligence Technology》 2016年第3期210-224,共15页
Indoor multi-tracking is more challenging compared with outdoor tasks due to frequent occlusion, view-truncation, severe scale change and pose variation, which may bring considerable unreliability and ambiguity to tar... Indoor multi-tracking is more challenging compared with outdoor tasks due to frequent occlusion, view-truncation, severe scale change and pose variation, which may bring considerable unreliability and ambiguity to target representation and data association. So discriminative and reliable target representation is vital for accurate data association in multi-tracking. Pervious works always combine bunch of features to increase the discriminative power, but this is prone to error accumulation and unnecessary computational cost, which may increase ambiguity on the contrary. Moreover, reliability of a same feature in different scenes may vary a lot, especially for currently widespread network cameras, which are settled in various and complex indoor scenes, previous fixed feature selection schemes cannot meet general requirements. To properly handle these problems, first, we propose a scene-adaptive hierarchical data association scheme, which adaptively selects features with higher reliability on target representation in the applied scene, and gradually combines features to the minimum requirement of discriminating ambiguous targets; second, a novel depth-invariant part-based appearance model using RGB-D data is proposed which makes the appearance model robust to scale change, partial occlusion and view-truncation. The introduce of RGB-D data increases the diversity of features, which provides more types of features for feature selection in data association and enhances the final multi-tracking performance. We validate our method from several aspects including scene-adaptive feature selection scheme, hierarchical data association scheme and RGB-D based appearance modeling scheme in various indoor scenes, which demonstrates its effectiveness and efficiency on improving multi-tracking performances in various indoor scenes. 展开更多
关键词 Multiple objects tracking Scene-adaptive data association Appearance model RGB-D data
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Multi-objective Firefly Algorithm for Test Data Generation with Surrogate Model
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作者 Wenning Zhang Qinglei Zhou +1 位作者 Chongyang Jiao Ting Xu 《国际计算机前沿大会会议论文集》 2021年第1期283-299,共17页
To solve the emerging complex optimization problems, multi objectiveoptimization algorithms are needed. By introducing the surrogate model forapproximate fitness calculation, the multi objective firefly algorithm with... To solve the emerging complex optimization problems, multi objectiveoptimization algorithms are needed. By introducing the surrogate model forapproximate fitness calculation, the multi objective firefly algorithm with surrogatemodel (MOFA-SM) is proposed in this paper. Firstly, the population wasinitialized according to the chaotic mapping. Secondly, the external archive wasconstructed based on the preference sorting, with the lightweight clustering pruningstrategy. In the process of evolution, the elite solutions selected from archivewere used to guide the movement to search optimal solutions. Simulation resultsshow that the proposed algorithm can achieve better performance in terms ofconvergence iteration and stability. 展开更多
关键词 Firefly algorithm Multi objective optimization Surrogate model Test data generation
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Data Model Transformation in CAD System for Multi View Modeling 被引量:1
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作者 Toyohiko Hirota, Masaaki Hashimoto Kyushu Institute of Technology, 680 4 Kawazu, Iizuka, Fukuoka 820 8502, Japan 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期410-415,共6页
This paper describes multi view modeling and data model transformation for the modeling. We have proposed a reference model of CAD system generation, which can be applied to various domain specific languages. Howeve... This paper describes multi view modeling and data model transformation for the modeling. We have proposed a reference model of CAD system generation, which can be applied to various domain specific languages. However, the current CAD system generation cannot integrate data of multiple domains. Generally each domain has its own view of products. For example, in the domain of architectural structure, designers extract the necessary data from the data in architecture design. Domain experts translate one view into another view beyond domains using their own brains.The multi view modeling is a way to integrate product data of multiple domains, and make it possible to translate views among various domains by computers. 展开更多
关键词 CAD data model program generation object\|oriented database
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Performance Monitoring of the Data-driven Subspace Predictive Control Systems Based on Historical Objective Function Benchmark 被引量:3
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作者 王陆 李柠 李少远 《自动化学报》 EI CSCD 北大核心 2013年第5期542-547,共6页
关键词 预测控制系统 性能监控 数据驱动 子空间 历史 基准 监视控制器 目标函数
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AN INTEGRATED DATA MODEL IN THREE DIMENSIONAL GIS 被引量:2
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作者 Gong Jianya Xia Zongguo 《Geo-Spatial Information Science》 1999年第1期1-8,15,共9页
The current GIS can only deal with 2-D or 2.5-D information on the earth surface. A new 3-D data structure and data model need to be designed for the 3-D GIS. This paper analyzes diverse 3-D spatial phenomena from min... The current GIS can only deal with 2-D or 2.5-D information on the earth surface. A new 3-D data structure and data model need to be designed for the 3-D GIS. This paper analyzes diverse 3-D spatial phenomena from mine to geology and their complicated relations, and proposes several new kinds of spatial objects including cross-section, column body and digital surface model to represent some special spatial phenomena like tunnels and irregular surfaces of an ore body. An integrated data structure including vector, raster and object-oriented data models is used to represent various 3-D spatial objects and their relations. The integrated data structure and object-oriented data model can be used as bases to design and realize a 3-D geographic information system. 展开更多
关键词 3-D GEOGRAPHIC INFORMATION system object-oriented data model VECTOR RASTER
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PORLES:A Parallel Object Relational Database System
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作者 Sun Yong\|qiang, Xu Shu\|ting, Zhu Feng\|hua, Lai Shu\|huaDepartment of Computer Science and Engineering, Shanghai Jiaotong University, Shanghai 200030,China 《Wuhan University Journal of Natural Sciences》 CAS 2001年第Z1期100-109,共10页
We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel que... We developed a parallel object relational DBMS named PORLES. It uses BSP model as its parallel computing model, and monoid calculus as its basis of data model. In this paper, we introduce its data model, parallel query optimization, transaction processing system and parallel access method in detail. 展开更多
关键词 parallel object relational database BSP model data model query optimization
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Spatial Object Aggregation Based on Data Structure, Local Triangulation and Hierarchical Analyzing Method
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作者 LIU Yaolin Martien Molenaar +1 位作者 Menno-Jan Kraak LIU Yanfang 《Geo-Spatial Information Science》 2002年第1期44-54,共11页
This paper focuses on the methods and process of spatial aggregation based on semantic and geometric characteristics of spatial objects and relations among the objects with the help of spatial data structure (Formal D... This paper focuses on the methods and process of spatial aggregation based on semantic and geometric characteristics of spatial objects and relations among the objects with the help of spatial data structure (Formal Data Structure),the Local Constrained Delaunay Triangulations and semantic hierarchy.The adjacent relation among connected objects and unconnected objects has been studied through constrained triangle as elementary processing unit in aggregation operation.The hierarchical semantic analytical matrix is given for analyzing the similarity between objects types and between objects.Several different cases of aggregation have been presented in this paper. 展开更多
关键词 AGGREGATION spatial object HIERARCH data model
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Modeling and OLAP Cubes for Database of Ground and Municipal Water Supply
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作者 Taskeen Zaidi Annapurna Singh Vipin Saxena 《Computational Water, Energy, and Environmental Engineering》 2013年第3期77-82,共6页
Modeling plays an important role for the solution of the complex research problems. When the database became large and complex then it is necessary to create a unified model for getting the desired information in the ... Modeling plays an important role for the solution of the complex research problems. When the database became large and complex then it is necessary to create a unified model for getting the desired information in the minimum time and to implement the model in a better way. The present paper deals with the modeling for searching of the desired information from a large database by storing the data inside the three dimensional data cubes. A sample case study is considered as a real data related to the ground water and municipal water supply, which contains the data from the various localities of a city. For the demonstration purpose, a sample size is taken as nine but when it becomes very large for number of localities of different cities then it is necessary to store the data inside data cubes. A well known object-oriented Unified Modeling Language (UML) is used to create Unified class and state models. For verification purpose, sample queries are also performed and corresponding results are depicted. 展开更多
关键词 modelING dataBASE object-oriented UNIFIED modelING Language OLAP data CUBES Water Supply
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LayeredModel:一个面向室内空间的移动对象数据模型 被引量:7
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作者 赵磊 金培权 +2 位作者 张蓝蓝 王怀帅 岳丽华 《计算机研究与发展》 EI CSCD 北大核心 2011年第S3期274-281,共8页
基于室内空间的移动对象管理或称室内移动对象管理,是一个崭新而又富有挑战的研究领域.如何建立语义完备并且支持多种应用的室内移动对象模型是一个重要的基础性问题.提出了一个分层的室内移动对象数据模型:LayeredModel.该模型提出了... 基于室内空间的移动对象管理或称室内移动对象管理,是一个崭新而又富有挑战的研究领域.如何建立语义完备并且支持多种应用的室内移动对象模型是一个重要的基础性问题.提出了一个分层的室内移动对象数据模型:LayeredModel.该模型提出了室内空间距离的概念,并使用不同的层次关系表达室内元素、传感器以及移动对象之间的关系.从而能支持多种基于室内空间的应用,例如移动对象的跟踪、监控、导航以及室内最近邻查询等.LayeredModel模型也为后续的室内移动对象的索引、查询的研究奠定了基础. 展开更多
关键词 室内空间 分层模型 移动对象 数据模型
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用SuperMap Object开发基于GIS的连锁店配送信息系统 被引量:3
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作者 尹涛 《计算机工程与设计》 CSCD 北大核心 2006年第17期3189-3192,共4页
支撑整个连锁店运营过程的是基于GIS的连锁店配送信息系统。在明确了业务流程的基础上,研究了基于GIS的连锁店配送信息系统的功能、GIS平台、空间数据模型、道路数据模型和最优路径分析,探讨了以SuperMapObjects作为GIS平台,采用Microso... 支撑整个连锁店运营过程的是基于GIS的连锁店配送信息系统。在明确了业务流程的基础上,研究了基于GIS的连锁店配送信息系统的功能、GIS平台、空间数据模型、道路数据模型和最优路径分析,探讨了以SuperMapObjects作为GIS平台,采用MicrosoftVisualBasic作为开发工具实现基于GIS的连锁店配送信息系统的方案。 展开更多
关键词 连锁店配送信息系统 地理信息系统 SUPERMAP object 空间数据模型 道路数据模型 最优路径
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基于面向对象技术和标准关系数据库的Geodatabase的研究 被引量:3
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作者 刘艳丰 姜耀鹏 《测绘与空间地理信息》 2009年第4期139-142,共4页
面向对象技术为空间数据模型的发展提出了新的要求。本论文在此背景下,回顾了空间数据模型的发展历程,从整体上介绍了第三代基于面向对象技术和关系数据库的Geodatabase数据模型,并详细介绍了其体系结构及在关系数据库中的存储。最后本... 面向对象技术为空间数据模型的发展提出了新的要求。本论文在此背景下,回顾了空间数据模型的发展历程,从整体上介绍了第三代基于面向对象技术和关系数据库的Geodatabase数据模型,并详细介绍了其体系结构及在关系数据库中的存储。最后本文通过总结Geodatabase模型的优缺点,提出了未来空间数据模型的发展趋势。 展开更多
关键词 面向对象 空间数据模型 GEOdataBASE 关系数据库
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面向对象空间数据模型——Geodatabase及其实现 被引量:28
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作者 陈静 张树文 《国土与自然资源研究》 2003年第2期44-46,共3页
通过回顾地理数据模型的发展历程,介绍了RACGIS8所推出的新型的面向对象的空间数据模型——Geodatabase的产生及其特点;分析了Geodatabase数据模型在空间信息存储与管理方面的优势,并对模型的实现过程予以阐述。
关键词 面向对象 空间数据模型 GEOdataBASE 地理数据模型 空间信息存储 GIS 地理信息系统 数据库
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利用Geodatabase建模
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作者 杨正银 《四川测绘》 2007年第6期248-251,共4页
本文介绍了采用面向对象技术的新一代地理数据模型Geodatabase的特点,举例说明了利用Geodatabase数据模型对地理对象建模的过程及其在数字中国地理空间框架建设中的重要意义。
关键词 特征 特征集 面向对象数据模型 关系-对象数据库
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第三代地理数据模型——Geodatabase及其实现 被引量:8
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作者 郭新慧 张和生 《太原科技大学学报》 2008年第1期5-8,共4页
简要阐述了地理数据模型的发展历程,详细分析了Geodatabase数据模型及其特点,并结合实例说明了Geodatabase数据模型的实现过程,从而验证了Geodatabase数据模型对于处理复杂地理对象具有强大的优越性。
关键词 地理数据模型 GEOdataBASE 面向对象
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基于FME Object的多源数据坐标转换关键技术实现 被引量:10
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作者 谢梓威 范冲 +1 位作者 王东亮 陈旭帅 《测绘与空间地理信息》 2016年第1期190-192,197,共4页
介绍了当前空间数据坐标转换的常用方法,特别是对基于FME的空间数据坐标转换的方法进行了分类总结。针对测绘成果基准各异、格式多样的特点,介绍了采用FME object技术实现多源数据坐标转换系统的开发。针对当前空间数据转换难以保证完... 介绍了当前空间数据坐标转换的常用方法,特别是对基于FME的空间数据坐标转换的方法进行了分类总结。针对测绘成果基准各异、格式多样的特点,介绍了采用FME object技术实现多源数据坐标转换系统的开发。针对当前空间数据转换难以保证完整性和正确性的问题,总结了利用FME object读写空间数据的关键技术。此外,文章还介绍了坐标转换过程中转换模型选择和参数计算的方法。 展开更多
关键词 FME FME object 坐标转换 空间数据 四参数
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A new GIS-compatible methodology for visibility analysis in digital surface models of earth sites 被引量:2
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作者 Katerina Ruzickova Jan Ruzicka Jan Bitta 《Geoscience Frontiers》 SCIE CAS CSCD 2021年第4期21-33,共13页
As a GIS tool,visibility analysis is used in many areas to evaluate both visible and non-visible places.Visibility analysis builds on a digital surface model describing the terrain morphology,including the position an... As a GIS tool,visibility analysis is used in many areas to evaluate both visible and non-visible places.Visibility analysis builds on a digital surface model describing the terrain morphology,including the position and shapes of all objects that can sometimes act as visibility barriers.However,some barriers,for example vegetation,may be permeable to a certain degree.Despite extensive research and use of visibility analysis in different areas,standard GIS tools do not take permeability into account.This article presents a new method to calculate visibility through partly permeable obstacles.The method is based on a quasi-Monte Carlo simulation with 100 iterations of visibility calculation.Each iteration result represents 1%of vegetation permeability,which can thus range from 1%to 100%visibility behind vegetation obstacles.The main advantage of the method is greater accuracy of visibility results and easy implementation on any GIS software.The incorporation of the proposed method in GIS software would facilitate work in many fields,such as architecture,archaeology,radio communication,and the military. 展开更多
关键词 Digital surface model Visibility analysis Topographic data processing Obstacle object PERMEABILITY
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Multi-source heterogeneous data access management framework and key technologies for electric power Internet of Things 被引量:1
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作者 Pengtian Guo Kai Xiao +1 位作者 Xiaohui Wang Daoxing Li 《Global Energy Interconnection》 EI CSCD 2024年第1期94-105,共12页
The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initiall... The power Internet of Things(IoT)is a significant trend in technology and a requirement for national strategic development.With the deepening digital transformation of the power grid,China’s power system has initially built a power IoT architecture comprising a perception,network,and platform application layer.However,owing to the structural complexity of the power system,the construction of the power IoT continues to face problems such as complex access management of massive heterogeneous equipment,diverse IoT protocol access methods,high concurrency of network communications,and weak data security protection.To address these issues,this study optimizes the existing architecture of the power IoT and designs an integrated management framework for the access of multi-source heterogeneous data in the power IoT,comprising cloud,pipe,edge,and terminal parts.It further reviews and analyzes the key technologies involved in the power IoT,such as the unified management of the physical model,high concurrent access,multi-protocol access,multi-source heterogeneous data storage management,and data security control,to provide a more flexible,efficient,secure,and easy-to-use solution for multi-source heterogeneous data access in the power IoT. 展开更多
关键词 Power Internet of Things object model High concurrency access Zero trust mechanism Multi-source heterogeneous data
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An Object-Oriented Transaction Model
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作者 顾君忠 《Journal of Computer Science & Technology》 SCIE EI CSCD 1993年第4期289-306,共18页
In object-oriented database systems(OODBSs),the traditional transaction models are no longer suit- able because of the difference between the object-oriented data model(OODM)and the conventional da- ta models(e.g.rela... In object-oriented database systems(OODBSs),the traditional transaction models are no longer suit- able because of the difference between the object-oriented data model(OODM)and the conventional da- ta models(e.g.relational data model).In this paper,transaction models for advanced databuse applica- tions are reviewed and their shortcomings are analyzed.Exchangeability of operations is proposed in- stead of commuativity and recoverability for using more semantics in transaction management.As a result,an object-oriented transaction model(in short,OOTM)is presented.It is not modeled for some special application,but directly based on object-oriented paradigms.A transaction is regarded as an interpretation of a method.Each transaction(even subtransactions)keeps relative ACID(Atomicity, Consistency,Isolation,Durability )properties,therefore the special problems appearing in OODBSs such as“long transactions”,“visibility of inconsistent database state”can be solved. 展开更多
关键词 objects methods TRANSACTIONS object-oriented data model (OODM) object-oriented database system (OODBS) object-oriented transaction model (OOTM) relative ACID EXCHANGEABILITY
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