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1.
针对有限空间下如何快速维护概念格的问题,提出一种消减形式背景中冗余二元关系的概念格维护算法。传统的算法删除冗余关系后需要重新构造概念格,这种方式较为费时。而所提算法能够在原始概念格的基础上直接调整得到新概念格的方法,可以处理任意位置的二元关系消减的情况。它采用自底向上广度优先方式遍历格节点,首先根据当前节点是否同时包含冗余关系对象和冗余关系属性,将当前节点分为受影响的节点和不变节点;然后根据当前节点与父子节点的外延和内涵的关系,再将受影响的节点细分为4类,即减对象节点、减属性节点、分割节点、删除节点;最后根据父子节点的类型更新边。实验结果表明,在一定程度上与传统算法相比,所提算法能够获得更好的时间性能。 相似文献
2.
概念格的属性渐减原理与算法研究 总被引:1,自引:0,他引:1
渐进式算法是概念格构造的一类重要算法,但大多关注于形式背景中对象或属性增加的情况.而当形式背景的属性减少时,已有的算法则需要重新构造概念格,较为费时.针对这一情况,研究了属性消减后从原概念格渐进式产生新概念格的理论和算法,并且算法时间复杂度较低.首先分析了原概念格和新概念格中节点间的映射关系以及从原概念格到新概念格中边(节点间的前驱-后继关系)的变化规律.在此基础上,提出了自顶向下和自底向上两种渐进式的概念格属性渐减算法.算法能够对原有概念格直接进行修改来得到新的概念格,避免了从形式背景重新构造概念格,时间复杂度降低为O(‖ L ‖·G ‖·‖M ‖).实验及分析表明,当属性减少时,能比传统算法节省大量的运行时间. 相似文献
3.
一般的模糊概念格在构造过程中没有考虑用户的需求,用户对模糊概念格节点中一些属性集形成的内涵并不感兴趣。为了增强模糊概念格的针对性,降低模糊概念格构造的时空复杂性,构造满足用户需求的模糊概念格,首先将用户感兴趣的背景知识定义为约束条件,根据用户关心的属性间关系,将约束条件分为3类:单约束、与约束及或约束,并采用谓词公式表示,进而提出了基于约束的模糊概念格(Constrained Fuzzy Concept Lattice,CFCL)构造算法。该算法自底向上构造模糊概念格,利用模糊概念格父子节点内涵的单调关系,采用剪枝技术来减少构造过程中判断模糊概念是否满足约束的次数,提高了模糊概念格的构造效率。实验结果表明,该算法能够有效地减少模糊概念格的存储空间和构格时间。 相似文献
4.
针对区间概念格Lβα(U, A, R)的概念外延在区间[α, β](0≤α≤β≤1)范围内满足内涵属性的特性, 提出基于属性集合幂集的区间概念格Lβα的渐进式生成算法, 以提高区间概念格的建格效率。在格结构的生成过程中, 将节点分为不变节点、更新节点、新增节点。算法首先由属性集合幂集生成所有节点的内涵, 之后根据区间概念格中父子节点的独特性质自下而上渐进式地构造格结构。通过算法分析与实例证明了优化后的渐进式生成算法提高了建格效率。 相似文献
5.
《计算机应用与软件》2016,(7)
形式概念分析理论在诸多计算机领域得到广泛应用。模糊概念格的构造仍是其在应用过程中的一个主要问题。为提高模糊概念格的构造效率,对串行算法进行并行化改造,提出模糊概念格的并行构造算法。该算法对节点进行层次划分,给出了同层节点的定义,得出同层节点构造任务相互独立的重要性质,并引入映射函数简化搜索空间的遍历,提高搜索模糊概念格的效率,并行构造模糊概念格,达到了提高构造效率的目的。实验表明该算法在面对大规模的构造任务时,具有良好的性能。 相似文献
6.
一种模糊概念格模型及其渐进式构造算法 总被引:4,自引:0,他引:4
传统形式概念分析方法无法处理现实中模糊和不确定信息,因此,对模糊概念格及其信息表示的研究具有重要意义.文中提出了一种模糊概念格模型,提出了模糊形式背景中属性隶属度值的窗口截取方法,定义了模糊概念的模糊参数σ和λ,给出了模糊概念格渐进式构造算法,推导出了模糊参数σ和λ的渐进式计算公式.模糊参数σ和λ分别体现了概念外延对于属性的隶属度的均值和发散程度.在模糊概念格渐进式构造算法中引入两个中间参数以实现模糊参数的渐进式计算.最后,进行了算法性能评估实验,结果表明模糊概念格的这种渐进式构造算法在时间上和空间上都具有良好的性能. 相似文献
7.
区间概念格是唯一能直接反映具备一定数量或比例的内涵中属性的对象集合的格结构。格结构是根据对象-属性的二元关系构造的,形式背景中的属性是时刻变化的,为使概念格能反映属性变化后的数据规律进而提取新的规则,提出了区间概念格的纵向维护算法。算法在分析了区间概念格的概念外延特点及结构特征后,给出了区间概念格在增加属性、删除属性两种情况下的维护算法,进而通过算法分析表明了维护较重构在时间与空间上的高效性,最终用实例表明了维护算法的可行性。 相似文献
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9.
概念格的快速渐进式构造算法 总被引:66,自引:2,他引:66
概念格作为形式概念分析理论中的核心数据结构,已经在知识工程和软件工程等领域得到了广泛的应用。概念格的快速构造在其应用过程中具有重要的意义,研究人员已经提出了一系列构造概念格的算法,其中渐进式算法是很有前途的一类。该文通过对概念格渐进式构造过程的分析,识别出要解决的基本问题,提出了采用树结构对概念格节点进行组织,研究了基于这种树状组织的概念格快速渐进式算法,并给出了算法的伪码。概念格节点的树结构组织有利于识别出格节点的类型以及约束新生格节点的父节点和子节点的搜索范围,从而可以有效地减少算法的执行时间。实验结果表明,基于这种树状索引的渐进式构造算法的时间性能要明确优于著名的Godin算法。 相似文献
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11.
S. Shaw 《Journal of Computer Assisted Learning》1993,9(2):93-99
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
C. Lloyd 《Journal of Computer Assisted Learning》1993,9(2):86-91
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.
Wayne O’Brien Author Vitae 《Journal of Systems and Software》2008,81(11):1997-2013
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.
David Poole 《Computational Intelligence》1989,5(2):97-110
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.
Watts S. Humphrey 《Annals of Software Engineering》2002,14(1-4):39-72
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.
R. NOSS 《Journal of Computer Assisted Learning》1987,3(1):2-12
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