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1.
We investigate an automated identification of weak signals according to Ansoff to improve strategic planning and technological forecasting. Literature shows that weak signals can be found in the organization’s environment and that they appear in different contexts. We use internet information to represent organization’s environment and we select these websites that are related to a given hypothesis. In contrast to related research, a methodology is provided that uses latent semantic indexing (LSI) for the identification of weak signals. This improves existing knowledge based approaches because LSI considers the aspects of meaning and thus, it is able to identify similar textual patterns in different contexts. A new weak signal maximization approach is introduced that replaces the commonly used prediction modeling approach in LSI. It enables to calculate the largest number of relevant weak signals represented by singular value decomposition (SVD) dimensions. A case study identifies and analyses weak signals to predict trends in the field of on-site medical oxygen production. This supports the planning of research and development (R&D) for a medical oxygen supplier. As a result, it is shown that the proposed methodology enables organizations to identify weak signals from the internet for a given hypothesis. This helps strategic planners to react ahead of time.  相似文献   

2.
The aim of cross impact analysis (CIA) is to predict the impact of a first event on a second. For organization’s strategic planning, it is helpful to identify the impacts among organization’s internal events and to compare these impacts to the corresponding impacts of external events from organization’s competitors. For this, literature has introduced compared cross impact analysis (CCIA) that depicts advantages and disadvantages of the relationships between organization’s events to the relationships between competitors’ events. However, CCIA is restricted to the use of patent data as representative for competitors’ events and it applies a knowledge structure based text mining approach that does not allow considering semantic aspects from highly unstructured textual information. In contrast to related work, we propose an internet based environmental scanning procedure to identify textual patterns represent competitors’ events. To enable processing of this highly unstructured textual information, the proposed methodology uses latent semantic indexing (LSI) to calculate the compared cross impacts (CCI) for an organization. A latent semantic subspace is built that consists of semantic textual patterns. These patterns are selected that represent organization’s events. A web mining approach is used for crawling textual information from the internet based on keywords extracted from each selected pattern. This textual information is projected into the same latent semantic subspace. Based on the relationships between the semantic textual patterns in the subspace, CCI is calculated for different events of an organization. A case study shows that the proposed approach successfully calculates the CCI for technologies processed by a governmental organization. This enables decision makers to direct their investments more targeted.  相似文献   

3.
基于Rough集潜在语义索引的Web文档分类   总被引:5,自引:0,他引:5  
Rough集(粗糙集)埋论是一种处理不确定或模糊知识的数学工具。提出了一种基于Rough集理论的潜在语义索引的Web文档分类方法。首先应用向量空间模型表示Web文档信息,然后通过矩阵的奇异值分解来进行信息过滤和潜在语义索引;运用属性约简算法生成分类规则,最后利用多知识库进行文档分类。通过试验比较,该方法具有较好的分类效果。  相似文献   

4.
基于潜在语义索引和句子聚类的中文自动文摘   总被引:2,自引:0,他引:2  
自动文摘是自然语言处理领域的一项重要的研究课题.提出一种基于潜在语义索引和句子聚类的中文自动文摘方法.该方法的特色在于:使用潜在语义索引计算句子的相似度,并将层次聚类算法和K-中心聚类算法相结合进行句子聚类,这样提高了句子相似度计算和主题划分的准确性,有利于生成的文摘在全面覆盖文档主题的同时减少自身的冗余.实验结果验证了该文提出的方法的有效性,对比传统的基于聚类的自动文摘方法,该方法生成的文摘质量获得了显著的提高.  相似文献   

5.
语义网、语义网格和语义网络   总被引:9,自引:0,他引:9  
语义网、语义网格和语义网络是三个容易混淆的概念,语义网是对WWW的延伸,其目标是使得Web上的信息具有计算机可以理解的语义,并为人们提供各种智能服务;语义网格是语义Web和网格相结合产生的新的研究领域;语义网络是知识的一种图解表示,它由节点和弧线或链线组成.通过对三者的概念、特征、应用等方面进行介绍从而说明了三者的联系以及不同,并说明了今后对三者的研究方向和重点问题.  相似文献   

6.
We develop a new algorithm for clustering search results. Differently from many other clustering systems that have been recently proposed as a post-processing step for Web search engines, our system is not based on phrase analysis inside snippets, but instead uses latent semantic indexing on the whole document content. A main contribution of the paper is a novel strategy – called dynamic SVD clustering – to discover the optimal number of singular values to be used for clustering purposes. Moreover, the algorithm is such that the SVD computation step has in practice good performance, which makes it feasible to perform clustering when term vectors are available. We show that the algorithm has very good classification performance, and that it can be effectively used to cluster results of a search engine to make them easier to browse by users. The algorithm has being integrated into the Noodles search engine, a tool for searching and clustering Web and desktop documents.  相似文献   

7.
    
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8.
刘宙  程学先  刘宇 《微机发展》2006,16(11):28-31
语义网络数据挖掘是基于语义网络环境的数据挖掘,它给数据挖掘技术的应用研究提出了新的课题。归纳逻辑程序设计是由机器学习与逻辑程序设计交叉所形成的一个研究领域,它为知识工程等人工智能的应用领域提供了新的强有力的技术支持。分析了现有几种常用数据挖掘技术在语义Web环境下应用的局限性,提出了采用归纳逻辑程序设计(ILP)作为语义Web上适合的数据挖掘技术,给出了应用这种技术的算法描述,通过具体实例验证了其可行性。  相似文献   

9.
基于潜在语义标引的WEB文档自动分类   总被引:6,自引:1,他引:6  
Web挖掘技术在商业上有广泛的应用前景,但现有的Web挖掘技术存在计算量大,精度不高等问题。论文提出的LSIWAC算法,首先运用潜在语义标引技术将Web页面词空间压缩到低维的特征空间;然后,在得到的特征空间上运用最优聚类将样本集合分为若干簇;对得到的每簇鉴别特征再利用最佳鉴别变换进行压缩和特征抽取,并用最终得到的特征矢量进行分类。该方法克服了样本高维效应,有效提高分类准确率,降低计算量。实验结果验证所提方法的有效性。  相似文献   

10.
Cross impact analysis (CIA) consists of a set of related methodologies that predict the occurrence probability of a specific event and that also predict the conditional probability of a first event given a second event. The conditional probability can be interpreted as the impact of the second event on the first. Most of the CIA methodologies are qualitative that means the occurrence and conditional probabilities are calculated based on estimations of human experts. In recent years, an increased number of quantitative methodologies can be seen that use a large number of data from databases and the internet. Nearly 80% of all data available in the internet are textual information and thus, knowledge structure based approaches on textual information for calculating the conditional probabilities are proposed in literature. In contrast to related methodologies, this work proposes a new quantitative CIA methodology to predict the conditional probability based on the semantic structure of given textual information. Latent semantic indexing is used to identify the hidden semantic patterns standing behind an event and to calculate the impact of the patterns on other semantic textual patterns representing a different event. This enables to calculate the conditional probabilities semantically. A case study shows that this semantic approach can be used to predict the conditional probability of a technology on a different technology.  相似文献   

11.
基于动态网站的语义数据挖掘模型研究   总被引:1,自引:0,他引:1  
WEB使用挖掘正逐渐成为WEB个性化服务领域的研究重点,它通过对用户历史使用信息的分析,实现网站的个性化服务。然而,由于动态网页对象URL结构的特殊性,导致了WEB使用挖掘在动态网站应用上的局限性。论文在基于WEB使用挖掘分析的基础上,针对动态网站数据挖掘和个性化服务,提出了语义数据挖掘模型,并详细描述该模型的挖掘流程。  相似文献   

12.
介绍潜在语义索引中半离散矩阵分解SDD(Semidiscrete Matrix Decomposition)方法的使用,改进其在存储空间方面的不足,提出了SDD 方法,并比较了奇异值分解SVD(Singular Vector Decomposition)、SDD和SDD 的性能差异.  相似文献   

13.
万彬王卫疆  汪秉文 《微机发展》2005,15(7):135-137,151
对语义Web技术和现行Web服务技术进行了简述,说明了将Web Services技术与语义Web技术的糅合可以大幅度地提高Web服务的质量,详细介绍了DAML—S语义Web服务语言,阐述了语义Web技术与Web服务技术结合的互补性和可行性。文中还给出了一个在现今WWW万维网上Web服务应用语义技术的一个简单的发现架构。  相似文献   

14.
This paper proposes a projection-based symmetrical factorisation method for extracting semantic features from collections of text documents stored in a Latent Semantic space. Preliminary experimental results demonstrate this yields a comparable representation to that provided by a novel probabilistic approach which reconsiders the entire indexing problem of text documents and works directly in the original high dimensional vector-space representation of text. The employed projection index is derived here from the a priori constraints on the problem. The principal advantage of this approach is computational efficiency and is obtained by the exploitation of the Latent Semantic Indexing as a preprocessing stage. Simulation results on subsets of the 20-Newsgroups text corpus in various settings are provided. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   

15.
Latent Semantic Kernels   总被引:5,自引:0,他引:5  
Kernel methods like support vector machines have successfully been used for text categorization. A standard choice of kernel function has been the inner product between the vector-space representation of two documents, in analogy with classical information retrieval (IR) approaches.Latent semantic indexing (LSI) has been successfully used for IR purposes as a technique for capturing semantic relations between terms and inserting them into the similarity measure between two documents. One of its main drawbacks, in IR, is its computational cost.In this paper we describe how the LSI approach can be implemented in a kernel-defined feature space.We provide experimental results demonstrating that the approach can significantly improve performance, and that it does not impair it.  相似文献   

16.
语义Web服务是应用语义Web技术对Web服务的扩展.使信息具有语义就是用计算机内的Ontology中的概念作标记符对信息进行标记,对该过程予以支持的就是语义Web技术,即Ontology的构建技术、Ontology的使用技术(语义推理技术)和信息的语义标记技术.语义Web技术对Web服务的扩展可具体化为两项任务:服务提供者、服务请求者和服务注册处三类服务主体均内置Ontology;发布、查找和绑定三种交互信息均采用语义标记.  相似文献   

17.
Falcon-F系统是一个语义网资源采集、索引和检索系统,本文对Falcon-F系统里语义网资源采集过程中的选种工作进行了阐述。首先介绍了语义网资源采集和目前的研究现状,然后重点阐述了语义网资源采集过程里选种的具体设计和实现,以及对相关问题的解决,最后是总结与展望。  相似文献   

18.
面向服务的语义网格框架及其关键技术   总被引:1,自引:0,他引:1  
曹蓉  褚伟  朱颖 《微机发展》2007,17(1):71-73
由于传统的网格存在信息格式异构等问题,导致网格无法像原先设想的那般高效无缝自动化,因此在网格中引入语义的概念,希望通过语义网格来弥补这种缺陷。分析了语义网格与网格及语义Web的关系,阐述了语义网格中与语义Web共享的关键技术,并基于面向服务的思想,提出了一个面向服务的语义网格框架,并对它做了详细的描述。  相似文献   

19.
语义元数据是有关Web内容语义信息的数据描述,它的有效表示及生成是构建语义Web的关键性技术。本文在讨论各种语义元数据的表示方法后,研究语义元数据的生成技术,在分析现有技术的特点和不足后,评述语义元数据生成技术的发展趋势。  相似文献   

20.
探讨了Web服务及本体,介绍了本体描述语言OWL及本体开发工具protégé,提出了一种基于本体的语义匹配方法,通过与其它方法进行比较.分析了该方法的优点。  相似文献   

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