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排序方式: 共有3774条查询结果,搜索用时 0 毫秒
71.
该文从安徽汽车产业集群信息服务平台检索需求出发,通过对平台现有检索技术进行分析,指出建立基于本体技术的智能检索系统的必要性,在此基础上构建了基于本体的产业集群信息检索模型,阐述了领域本体构建的重要性,最后指出产业集群信息检索的实现可以大大提高平台信息检索性能。 相似文献
72.
查询扩展是优化信息检索的一种有效方法。基于关键词的查询扩展对语义信息的忽略为结果带来了不好的影响,因而提出一种基于本体的查询扩展方法。首先建立本体模型,通过计算本体中的概念语义相似度和实例语义相似度,实现语义查询扩展。 相似文献
73.
基于用户浏览行为的用户模型调整算法研究 总被引:1,自引:0,他引:1
个性化信息服务越来越成为信息检索领域中研究的热点。针对用户模型构造问题,文章结合手工定制建模与自动分析建模技术;并改进文档特征向量的权重计算方式,提高特征向量表示文档的能力;并结合用户浏览行为的页面反馈度计算,提出了一种用户模型智能调整算法。模拟实验表明,该结构和算法能够有效地提高检索结果的准确度,并且具有良好的可适应性。 相似文献
74.
分析UML模型一致性检测的研究意义,以及UML类图推理的研究现状,提出一种基于OWL本体的UML类图推理方案.研究UML类图向OWL本体转换的映射规则,给出UML类图包含关系、可满足性、等价关系和相离关系的判断方法及其推理规则.利用Jena推理机制实现了UML类图包含关系、可满足性、等价关系和相离关系的推理. 相似文献
75.
Abstract: Managing multiple ontologies is now a core question in most of the applications that require semantic interoperability. The semantic web is surely the most significant application of this report: the current challenge is not to design, develop and deploy domain ontologies but to define semantic correspondences among multiple ontologies covering overlapping domains. In this paper, we introduce a new approach of ontology matching named axiom-based ontology matching. As this approach is founded on the use of axioms, it is mainly dedicated to heavyweight ontologies, but it can also be applied to lightweight ontologies as a complementary approach to the current techniques based on the analysis of natural language expressions, instances and/or taxonomical structures of ontologies. This new matching paradigm is defined in the context of the conceptual graphs model, where the projection (i.e. the main operator for reasoning with conceptual graphs which corresponds to homomorphism of graphs) is used as a means to semantically match the concepts and the relations of two ontologies through the explicit representation of the axioms in terms of conceptual graphs. We also introduce an ontology of representation, called MetaOCGL, dedicated to the reasoning of heavyweight ontologies at the meta-level. 相似文献
76.
Alexander Paar Jürgen Reuter John Soldatos Kostas Stamatis Lazaros Polymenakos 《Applied Intelligence》2009,30(1):37-46
Recently, several standards have emerged for ontology markup languages that can be used to formalize all kinds of knowledge.
However, there are no widely accepted standards yet that define APIs to manage ontological data. Processing ontological information
still suffers from the heterogeneity imposed by the plethora of available ontology management systems. Moreover, ubiquitous
computing environments usually comprise software components written in a variety of different programming languages, which
makes it particularly difficult to establish a common ontology management API with programming language agnostic semantics.
We implemented an ontological Knowledge Base Server, which can expose the functionality of arbitrary off-the-shelf ontology
management systems via a formally specified and well defined API. A case study was carried out in order to demonstrate the
feasibility of our approach to use a formally specified ontology management API to implement a registry for ubiquitous computing
systems. 相似文献
77.
Increasingly powerful computers and increased emphasis on evidence based decision making are creating a demand for merging
and integrating data from different sources into a single data set. The demand for data is outstripping our ability to ensure
data integrity, and sometimes analysis is performed on data that are not appropriate for the purposes they are used for. Here
we describe problems that arise when data from different sources are merged, and we suggest that one way to add context to
data so that users can make informed decisions about their ontological context is through ontology-based metadata. Examples
of the problem are taken from health data with emphasis on difficulties in standardizing Emergency Room wait times. We describe
eight fields that can be used to capture contextual metadata. These fields are captured using ethnographic methods from users
and database stewards who frequently understand precisely how context and institutional usage have shaped interpretation of
semantic fields. We argue that attaching a portable archive of ontological context to travel with data—based on information
from users and developers—is a means of ensuring that data are integrated and compared in multiple contexts with greater integrity
and more robust results.
相似文献
Nadine SchuurmanEmail: |
78.
Wen-Shyong Tzou Wei-Po Lee Bingchiang Jeng 《Expert systems with applications》2009,36(10):12605-12612
One major goal of functional genomics has been to identify and analyze molecular interactions in a cellular context to better understand the underlying design principles and mechanisms. To investigate into a PPI network from both topological and functional points of view, this work proposes a methodology that exploits ontology-based biological knowledge for network analysis. To speed up the procedure, an agent-based framework is also presented for supporting distributed computing. The preliminary results show that through the knowledge obtained from gene ontology, our work in analyzing building blocks of PPI networks can give a higher resolution than that of previous ones. Also our agent-based framework can successfully speed up the task of network analysis in an adaptive manner. 相似文献
79.
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