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1.
对象-关系-属性数据模型相对传统的结构化数据模型,用更丰富的数据语义区别了对象类属性和关系类型属性两个概念,使其适用于半结构化数据的存储与管理.从分析空间数据的半结构化特征入手,以空间数据的嵌套关系为管理对象,实现了在关系型数据库中对空间半结构化数据的存储与管理.  相似文献   

2.
由于半结构化数据缺乏模式信息,因而半结构化数据的存储与查询将是一个十分重要且具有挑战性的研究课题。利用关系数据库存储半结构化数据可以重用数据库的查询优化器和事务处理机制,能够保证半结构化数据的一致性和完整性。该文提出一种实现半结构化数据存储与查询的新方法,该方法使用关系数据库系统来实现半结构化数据的存储与查询。给出了把基于半结构化数据的查询重写为基于关系的查询的算法,同时介绍一个可视化查询程序。  相似文献   

3.
赵小凡  李情 《自动化仪表》2022,(3):65-68+74
为了提升半结构化数据的安全转换能力、降低数据转换输出误码率(BER),提出基于元数据管理的半结构化数据安全转换方法。构建云存储动态半结构化数据的Hash编码模型,采用动态随机码元调制方法,分析云存储动态半结构化数据的参数统计特征量。采用模糊自相关融合调度方法,构建云存储动态半结构化数据的直觉模糊度对偶集。采用统计分析和概率密度特征采样的方法,构建云存储动态半结构化数据分簇聚类融合模型。采用元数据管理和参数模糊度辨识,实现半结构化数据安全转换和多属性群决策。根据分组交换的方法,实现云存储动态半结构化数据动态分析和聚类。结合信息聚类和自适应学习方法,实现半结构化数据安全转换和编码控制。仿真结果表明,采用该方法进行半结构化数据安全转换的准确性较高、数据输出误码率较低、融合性较好,提高了半结构化数据的安全传输能力。  相似文献   

4.
一种基于XML的半结构化数据存储方法   总被引:6,自引:0,他引:6  
提出了一种基于XML存储半结构化数据的方法,设计并实现了相应存储与解析算法。鉴于OEM模型是一种图状模型,而通常的XML据模型是树状模型,为此需解决图状模型数据映射为树状模型数据这一关键问题,利用XML元素和属性的语义信息可从语义级别解决该问题。,  相似文献   

5.
潘顺  金远平 《计算机工程》2002,28(5):57-58,280
在分析现有的半结构化数据的存储方式及存在的问题基础上,引入了小集合属性、集合属性、聚类集合、模板集合、父属性序列等概念,借助映射表达语言STORED,提出了一种基于数据挖掘的半结构化数据到结构化数据的模式抽取的方法。  相似文献   

6.
一个基于模式的XML存储模型   总被引:4,自引:0,他引:4  
XML基于半结构化数据模型,而半结构化数据很难统一存储和管理。文章提出了一个基于模式的XML存储模型SBSM,并定义了如何在该模型上进行相关的操作,该模型克服了对象-关系映射模型的局限性,并支持直接在模型上进行查询操作。  相似文献   

7.
为了克服半结构化数据存储的不确定性,基于半结构化数据的结构信息可由其模式来描述的思想,提出一种动态树存储模型。在对对象交换模型OEM(Object Exchange Model)进行深度优先遍历,找出所有最大简单路径表达式基础上,采用累加计数原则将得到的最大路径表达式依次添加到一个动态树中,从而生成存储模型。最后将此模型映射到关系表中,实现了半结构化数据在关系数据库中的存储与查询。以村镇土地审批处理系统为实例来说明这种存储模型的有效性。  相似文献   

8.
通用映射模式下GML关系数据库存储研究*   总被引:1,自引:0,他引:1  
提出了一种将GML文档存储到关系数据库的存储映射模型G2RDB,通过解析GML文档,提取文档的要素信息、空间对象信息和嵌套关系等,根据预先定义的映射规则和要素模型的映射关系表,形成GML数据文档与关系数据库之间的关系模式映射表:要素信息表、要素模型映射表、同类要素属性信息表和空间对象信息表,将文档数据存储到RDBMS中,实现了GML文档的关系数据库存储,同时生成了同样可用于其他GML实例数据的通用映射关系表模式。在关系数据库存储方式下,应用SQL和自开发的空间操作算子函数可以实现GML数据的查询,依据映射  相似文献   

9.
针对当前标准对象存储系统的数据对象属性存储和检索方面的不足,结合空间应用数据对象特点,进行了对象属性设计,提出了一种基于HBase数据库的属性管理方法。该方法利用HBase数据库对数据对象及其属性进行集中管理,同时采用分段散列索引实现利用对象属性快速检索对象数据。测试结果表明,基于HBase数据库对象管理方法性能优于现有的属性管理方法,具有较高的对象属性检索效率。  相似文献   

10.
监控数据在不断增大,且80%以上为非结构化数据,利用传统关系型数据库存储管理时,占用机器内存较大,检索数据需对数据库全表扫描,管理性能低。为解决海量监控数据的存储与管理,采用HDFS分布式文件系统存储视频非结构化数据,研究设计Hbase属性信息表,利用Hbase分布式数据库存储属性信息,研究Hbase全局检索信息行键及MapReduce工作流程,构建检索,实现视频监控数据的检索。最终基于非结构化数据的检索技术以及分布式数据处理框架的研究,得到的海量监控数据存储与检索方案。  相似文献   

11.
Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.  相似文献   

12.
European Community policy and the market   总被引:1,自引:0,他引:1  
Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.  相似文献   

13.
融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。  相似文献   

14.
Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.  相似文献   

15.
This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.  相似文献   

16.
Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008  相似文献   

17.
Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.  相似文献   

18.
This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)SM and Team Software Process (TSP){SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.  相似文献   

19.
基于复小波噪声方差显著修正的SAR图像去噪   总被引:4,自引:1,他引:3  
提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。  相似文献   

20.
Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.  相似文献   

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