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1.
何富贵  刘仁金  张燕平  张铃 《计算机科学》2014,41(11):265-268,281
大规模网络路径问题是社会网络信息处理的基本问题。将粒计算方法引入到大规模网络研究中,结合社会网络分层和社团结构性质建立网络的多粒度层次模型,实现网络的多粒度存储,将大规模网络复杂结构映射到不同粒度空间中。为了降低问题求解的复杂度,将最短路径问题映射到不同粒度空间中,将搜索过程从粗粒度空间向细粒度空间跳转以搜索路径信息,提出基于多粒度空间的最短路径搜索算法(BGrR)来加速大规模网络路径搜索。在实验中,以城市道路交通网络为数据源,通过与A*和ALT方法比较,验证了所提算法的有效性。  相似文献   

2.
网络结构分析是人工智能领域基本问题。应用粒计算方法讨论了网络结构信息计算,从粒计算基本问题角度,采用商空间理论研究了网络结构粒化和粒化后不同粒度空间中的问题,特别是基于粒化如何计算不同粒层的粒间距离问题。应用方面,讨论了大规模网络结构最短路径搜索问题。作为大规模网络路径分析的预处理方法,选择社团作为基本粒,将大规模网络粒化到不同的粒度空间,形成不同粒度商空间的分层递阶粒度链。提出了基于分层递阶粒度链的大规模网络的启发式路径搜索方法。与A*和ALT方法进行了比较,验证了粒计算方法的有效性。  相似文献   

3.
网络路径搜索是图论中的经典问题,对于大规模网络的最短路径搜索问题是人工智能领域研究热点问题。应用粒计算方法求解问题的思路实现网络的粒度存储,讨论不同基本类型的网络粒化,提出分层递阶商空间链实现网络的粒度存储。就大规模网络,提出社团作为基本粒的网络快速分割方法,实现网络的粒度存储。并将网络的粒度存储的分层递阶商空间链信息作为路径搜索前的预处理工作,提出一种启发式路径搜索方法。通过实验与启发式算法进行对比,验证了该算法的有效性。  相似文献   

4.
商空间信息粒度模型可以从不同角度、不同层次观察问题.本文首先将商空间理论中论域合成技术进行推广,根据已知的粒度知识给出了粒度搜索范围,在问题求解中,降低了计算复杂度.然后讨论了模糊商空间粒度计算和分层递阶结构的关系,用不同粒度的商空间模型来表示聚类的结构.据此提出了基于Gaussian型函数的模糊聚类算法(G-FCluster算法),算法用距离表示信息粒度,不需要定义隶属函数和求出相似矩阵,并且不需要讨论参数的选择.将算法应用于中国证券市场,并与FCM算法进行比较.实验说明了算法可以很直观地从不同粒度(距离)观察聚类结果,大大降低了计算复杂度和空间复杂度,适于处理大数据量的样本.  相似文献   

5.
粒计算是研究和模拟人类认知从多粒度、多层次解决问题的方法,近年来成为智能信息处理中一个热点方向。云模型是一个基于概率理论研究定性定量转换认知模型的粒计算方法,通过正向和逆向云算法实现一组数据样本和一个基本概念之间的转换,但是目前的算法不能在整个问题域中解决多粒度、多概念的生成问题。概率统计中的高斯混合模型可以将任何一个频率分布函数转换成多个高斯分布的叠加,在此基础上,创新地提出用云模型中数字特征构建概念含混度作为概念外延共识程度的衡量,设计并实现了高斯云变换算法,将问题域中的数据分布自动转换为多粒度的不同概念,构建出人类概念认知中的泛概念树。通过在数据概念聚类和图像分割中的应用,验证了方法的有效性。  相似文献   

6.
粒计算是知识表示和数据挖掘的一个重要方法.从粒计算来看,一个粒是由多个比较小的颗粒组成的更大的一个单元.在许多实际应用中,由于不同标记尺度对数据集进行分割会得到不同层次的粒度,许多人在用粒计算解决问题时自然而然地考虑不同层次的粒度问题.这就促使思考如何选择一个合适的粒度层次来解决问题.围绕不完备多粒度决策系统,研究了基于局部最优粒度的规则提取方法.1)介绍了不完备多粒度决策系统的概念;2)在协调的不完备多粒度决策系统中定义了最优粒度和局部最优粒度、介绍了基于局部最优粒度的属性约简和规则提取方法,在不协调的不完备多粒度决策系统中引入了广义决策、定义了广义最优粒度和广义局部最优粒度,并给出了基于广义局部最优粒度的属性约简和规则提取方法;3)给出了在公开的数据集上的实验结果.  相似文献   

7.
随着具有结点属性信息的网络图数据的增加,结点属性及结点链接关系越来越复杂,这对复杂网络的链接预测任务带来了一系列的挑战.这些不同来源的原始数据之间存在着不一致性,即结点的属性诱导的潜在链接关系与网络拓扑结构观测到的链接边之间存在着不一致的情况,这一现象将直接影响结点对之间的链接预测准确性与精确性.为了有效处理多源数据的不一致性,融合异构数据的差异,借助粒计算思想,通过对原始数据的多粒度表示,将原始数据在不同层次的粒度进行信息表示建模.最终依据这些数据的粒度表示,寻找最优的粒层结构,并最大化地消除数据内在的不一致性.首先,定义了数据的粒度不同层次表示及粒层关系;其次,对所观测到的链接数据,构建对数似然统计模型,并综合不同粒度层数据特点对模型进行修正;最后,使用多源数据训练统计模型,将学习好的模型用于预测结点对之间的链接概率.实验表明:与现有链接预测模型相比,多源数据经过粒度表示极大地平衡了多源数据的不一致性,有效提升了链接预测任务的准确性.  相似文献   

8.
陈光  钟宁  姚一豫  黄佳进 《计算机科学》2011,38(12):209-212
粒计算三元论模型将现有粒计算研究成果的共性抽象出来,为问题求解提供了统一的方法论,而三元论模型是以多层次、多视角的粒结构为基础的。基于图的粒结构首先定义了图上的粒和层次,然后基于半序关系定义了图上的粒结构。在基于图的粒结构基础上,给出了实现不同粒度之间转换的“细化”、“粗化”运算符。“细化”运算处理从粗粒度到细粒度的转换,将粗粒度层次中的粒转换为细粒度层次中的粒,将粗粒度层次转换为细粒度层次。“粗化”运算处理从细粒度到粗粒度的转换,将细粒度层次中的粒转换为粗粒度层次中的粒,将细粒度层次转换为粗粒度层次。通过粒结构和“细化”、“粗化”运算,可以在不同的粒度上分析同一问题并使其在不同粒度之间自由转换。  相似文献   

9.
粒计算理论从多个角度、多个不同的粒度层次出发,对不确定、不精确或复杂的问题进行求解,现已成为人工智能领域研究的一种重要方法。针对决策系统属性约简与高效决策的粒度选择问题,分析了多粒度决策系统中信息粒与粒度划分的概念,定义了粒化度量和粒结构关于对象的粒化粗糙度,能够准确地反映决策系统中不同粒结构下的知识粒度大小。为弥补传统决策系统约简往往只考虑基于论域属性约简的缺陷,讨论了基于对象的局部约简方法,提出了基于论域和对象的决策系统最优粒度选择约简算法,并结合实例验证了该算法的有效性。  相似文献   

10.
粒度计算是一种新的智能计算的理论和方法,目前受到很多学者的关注。但是,具体可行的粒表示模型和不同粒的推理方法研究相对较少。本文将模糊粗糙集纳入粒度计算这种新的理论框架,对于处理复杂信息系统,求解复杂问题无疑具有重要的意义。首先利用笛卡尔积,构建了模糊关系下的信息粒;然后给出不同粒度下模糊粗糙算子的表示方法,进而形成一个分层递阶结构;最后考虑了对于模糊信息系统粒度粗细的选择问题,并给出一个实例,从而为粒度计算提供一个具体而实用的框架。  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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