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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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Using UML Behavioral Model to Support Aspect Oriented Model
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作者 Zahid Hussain Qaisar Nauman Anwar Shafiq Ur Rehman 《Journal of Software Engineering and Applications》 2013年第3期98-112,共15页
Aspect oriented software development is an emerging paradigm of software development. The notion of this technique is separation of concerns which means to implement each concern in a single object in object oriented ... Aspect oriented software development is an emerging paradigm of software development. The notion of this technique is separation of concerns which means to implement each concern in a single object in object oriented programming but still there are concerns which are distributed on different objects and are called crosscutting concerns while another form is Core concerns are the core functionality provided by the system but crosscutting concerns are the concerns like logging, performance etc. Modeling of aspect oriented software is different from the normal modeling of object-oriented or procedural language software, because aspects don’t have the independent identity or existence and they are tightly coupled to their woven context so it is difficult to model them. The one aim of our research paper is to explore the domain of Modeling of the aspect-oriented software. The goal of this research paper is to give a UML Behavioral modeling techniques in the domain of aspect oriented software development. This technique of generating UML Behavioral Model for aspects will give better understating of separations concerns. 展开更多
关键词 Aspects CONCERNS Cross Cutting CONCERNS Cut POINTS Join POINTS Advices META data UML and META model Aspect oriented modelING Software modelING
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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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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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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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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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An Open Architecture and Implementation for Product Data Management
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作者 张新访 《High Technology Letters》 EI CAS 1995年第2期1-6,共6页
In this paper, an open architecture and its implementation for product data management are presented. The system architecture, product data definition model, and a set of components of the architecture are discussed i... In this paper, an open architecture and its implementation for product data management are presented. The system architecture, product data definition model, and a set of components of the architecture are discussed in detail. Especially, the principle and some mechanism of one of the components, an object oriented database management system GH-EODB, are discussed in more detail. The architecture is extensible and adaptable. 展开更多
关键词 PRODUCT data MANAGEMENT PDES/STEP OBJECT oriented dataBASE PRODUCT model
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Study on 3D Geological Model of Highway Tunnels Modeling Method
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作者 Kun ZHENG Fang ZHOU +1 位作者 Pei LIU Peng KAN 《Journal of Geographic Information System》 2010年第1期6-10,共5页
Geology is the base for highways and tunnels construction. With the fast development of national highway construction, highway tunnel construction project are more and more complex. The completeness and accuracy are e... Geology is the base for highways and tunnels construction. With the fast development of national highway construction, highway tunnel construction project are more and more complex. The completeness and accuracy are essential for the planning, design and construction of projects, while the ground information is quite poor in systematic, reliable and timely aspects. Therefore, the development of underground road tunnels, and the implementation of informationized spatial information management is urgent for highway construction. 3D geological tunnel model is intuitive, high efficient and convenience which greatly facilitates the maintenance and security of highway tunnels construction and it will be the trend for the future highway tunnel development. 展开更多
关键词 oriented structure SEMANTIC TOPOLOGY RULE BASE 3D spatial data model
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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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FIRST ORDER LANGUAGE FOR ENTITY-ROLES MODEL^+
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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 1995年第1期59-63,共5页
With respect to the mathematical structure supposed by theEntity-Roles Model. a first order (three--valued) logic language is constructured. A world to be modelled can be logically specified in this language. The inte... With respect to the mathematical structure supposed by theEntity-Roles Model. a first order (three--valued) logic language is constructured. A world to be modelled can be logically specified in this language. The integrity constraints on the database and 展开更多
关键词 knowledge/data model EXPERT dataBASE object-orientATION dataBASE logic deductive QUERY
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Role Assignment and Cooperation of Ontology and Object-Oriented Principle in Construction of Digital Product Model
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作者 上官景昌 阎艳 +2 位作者 刘海涛 王国新 赵博 《Tsinghua Science and Technology》 SCIE EI CAS 2009年第S1期71-76,共6页
Powerful expressive ability of semantic information, to be easily computed and flexibility are basic features of digital product model (DPM). Using ontology and object-oriented principle (OOP) together to cope with pr... Powerful expressive ability of semantic information, to be easily computed and flexibility are basic features of digital product model (DPM). Using ontology and object-oriented principle (OOP) together to cope with problems in modeling is brought forward in this paper. The two are widely used and do well in modeling, but they each alone cannot cope with all issues and new challenges. Three basic requests are pointed out in DPM modeling. Status, problems, and root of current non-semantic and semantic models are introduced. Ontology, OOP, and their difference are introduced. It is found that the two are entirely complementary with each other. How to assign the roles and to cooperate for the two in coping with the three basic issues in DPM modeling are explained in detail. 展开更多
关键词 ONTOLOGY object-oriented principle digital product model data representation role assignment and cooperation
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创新驱动下的数据要素流动网络演化机制研究
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作者 吕承超 姜延杰 +1 位作者 何加豪 郭梦瑶 《科研管理》 北大核心 2025年第6期10-20,共11页
数据要素作为新型创新要素,培育经济增长的新动能,其有序流动是激发数据要素潜力的关键。本文基于数据要素流动环境视角,采用劳瑞引力模型构建数据要素流动空间关联网络,借助社会网络分析方法考察数据要素流动循环畅通情况,采用随机行... 数据要素作为新型创新要素,培育经济增长的新动能,其有序流动是激发数据要素潜力的关键。本文基于数据要素流动环境视角,采用劳瑞引力模型构建数据要素流动空间关联网络,借助社会网络分析方法考察数据要素流动循环畅通情况,采用随机行动者模型,探究空间网络结构演化驱动因素的作用机制,度量各驱动因素的相对重要性。结果表明:(1)数据要素流动呈现网络结构特征,各省份之间数据要素流动频繁,空间联动效应明显;(2)在“东数西算”等政策推动下,板块成员来源多元化,地区承担角色动态化,数据要素流动逐渐呈现多中心特征,数据要素流动空间关联网络的拓扑结构更复杂;(3)内生结构因素对网络结构演化发挥主导作用,各省份通过产业链加强分工合作促进数据要素流动。外生属性因素中,减少政府非市场干预,提升区域创新能力等有利于加快数据要素流动。本研究为全国统一大市场建设提供新视角。 展开更多
关键词 数据要素 空间关联网络 社会网络分析 驱动机制 随机行动者模型
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基于主体功能区规划的河南省生态效率测评及影响因素
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作者 杨勇 《地球科学与环境学报》 北大核心 2025年第4期693-705,共13页
主体功能区规划促进了社会经济与资源环境的协同发展,实施过程中采取的土地、产业、人口、财政等政策对生态效率产生显著影响。基于多源数据和超效率SBM模型,计算了2005~2018年河南省区县生态效率;采用变异系数、标准差椭圆系统刻画了... 主体功能区规划促进了社会经济与资源环境的协同发展,实施过程中采取的土地、产业、人口、财政等政策对生态效率产生显著影响。基于多源数据和超效率SBM模型,计算了2005~2018年河南省区县生态效率;采用变异系数、标准差椭圆系统刻画了县域尺度和主体功能区尺度生态效率演变规律;利用时空地理加权回归(GTWR)模型分析了主体功能区规划实施策略对生态效率空间异质性的影响。结果表明:(1)河南省生态效率整体处于较低水平,存在明显的空间集聚特征,区县差异随时间的推移有所减少;(2)国家级重点生态功能区平均生态效率最高,其次为国家级重点开发区与省级重点生态功能区,省级重点开发区与农产品主产区平均生态效率最低;(3)土地利用多样化指数、城镇化水平、产业结构、人口密度、地方财政一般支出额等因素对生态效率的影响具有显著的空间异质性,呈现出带状或片状空间分布规律。 展开更多
关键词 生态效率 时空演变 超效率SBM模型 时空地理加权回归模型 多源数据 空间分异 主体功能区 河南
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LLM+IEKEE:产教融合培养应用型大数据人才新范式
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作者 吕品 于文兵 《计算机教育》 2025年第12期120-126,共7页
针对现有的“知识+能力”的产教融合人才培养模式问题导向性训练不足等问题,提出LLM+IEKEE的产教融合教学新范式,将产教融合人才培养模式的重心从“知识+能力”向“问题+能力”转变,并以数据科学与大数据技术专业生产实习课程教学为例,... 针对现有的“知识+能力”的产教融合人才培养模式问题导向性训练不足等问题,提出LLM+IEKEE的产教融合教学新范式,将产教融合人才培养模式的重心从“知识+能力”向“问题+能力”转变,并以数据科学与大数据技术专业生产实习课程教学为例,具体阐述如何利用LLM+IEKEE范式帮助学生建立“问题+能力”的认知模式,激发其探索未知、解决问题的创新性能力,为人工智能时代应用型大数据人才的培养提供一条崭新的路径。 展开更多
关键词 大模型 产教融合 应用型 大数据 人才培养 元认知 数据科学
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数据要素三权分离的市场化配置机制及其激励契约研究 被引量:4
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作者 李珊 张文德 吴金东 《管理工程学报》 北大核心 2025年第2期89-104,共16页
数据要素市场化配置对我国数字经济发展至关重要,对数据要素的产权管理是解决目前供需缺口的主要方向。基于数据在不同流通场景下衍生出的数据权利,本文通过建立双重多任务委托代理模型进行效用分析,首次提出构建数据持有权、控制权和... 数据要素市场化配置对我国数字经济发展至关重要,对数据要素的产权管理是解决目前供需缺口的主要方向。基于数据在不同流通场景下衍生出的数据权利,本文通过建立双重多任务委托代理模型进行效用分析,首次提出构建数据持有权、控制权和使用权三权分离的市场化配置机制来解决数据配置问题。研究表明,该机制能够有效管控数据市场的垄断行为,满足多边利益最大化和数据市场发展诉求。研究发现,一个有效的数据要素三权分离的市场化配置机制有以下特征:(1)企业仅保留剩余控制权,并合理调配数据利用与数据脱敏两项任务的激励强度,使其增减相互制约,激励数据交易所对两项任务的努力水平进行按需分配,形成灵活的收益分配机制;(2)政府掌握剩余索取权,针对各类成本支付较高的情况,提高社会效益分成比例,对成本和风险进行补偿;(3)当数据脱敏努力水平与政府激励相关度不高,或政府加大监管力度时,政府能够通过调整税收比例或提供部分转移支付,提高社会效益分成比例。 展开更多
关键词 数据要素 市场化配置 产权配置 激励契约 委托代理模型
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医院大数据中心服务规范化建设研究
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作者 车贺宾 徐洪丽 +4 位作者 吴欢 乌日力格 胡苹 何昆仑 郭华源 《解放军医学院学报》 2025年第2期134-139,共6页
背景信息时代数据价值越来越受到人们的重视,近年来一些大型医院陆续建立大数据中心,系统化开展医疗数据资源开发利用工作。目的梳理解放军总医院医学大数据中心建设要点,总结服务经验。方法介绍解放军总医院医学大数据中心服务体系架... 背景信息时代数据价值越来越受到人们的重视,近年来一些大型医院陆续建立大数据中心,系统化开展医疗数据资源开发利用工作。目的梳理解放军总医院医学大数据中心建设要点,总结服务经验。方法介绍解放军总医院医学大数据中心服务体系架构、数据服务流程化模式、人员管理和数据安全管理。结果医学大数据中心支撑了解放军总医院多个国家、军队科研平台申报,成立6年产出与数据服务相关论文70篇,指导研究生近百名,有效发挥了医院科技创新公共平台的支撑作用。结论医院大数据中心服务规范化建设带来了医院管理及临床科研服务上的变革,有助于医院科研能力顺应时代潮流快速发展。 展开更多
关键词 医院大数据中心 医学数据服务 流程化模式
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