基于事件本体的突发事件领域知识建模

基于本体的知识建模方法有很多,在某些特定领域采用传统的本体建模方法存在着一些不足。以突发事件领域为例,提出了基于事件本体的知识建模方法。该模型分为上层事件类、下层事件类和事件实例,上层事件类描述的抽象的事件的分类体系,下层事件类是通过事件类关系组成的事件格结构。该模型不仅可以描述事件的时间、地点、对象等要素,还能描述事件类之间的关系。采用本体建模工具Protégé来构建突发事件领域本体,并以“恐怖袭击”作为实例验证了该模型的可用性。研究结果表明,该模型可以清晰地描述事件类的完整性,语义清晰,扩展性强。     

领域本体建模方法研究

介绍了本体的建模准则,详细分析了现有的本体建模方法,在现有的领域本体构建模式的基础上,通过借鉴其它本体的建立模式,提出了一种新的领域本体建模方法.该方法具有很强的逻辑性和可操作性,可被一些领域本体在建立时采用,所述方法用于构建高校教师本体过程中时效果非常好,体现出了该方法符合人类思维和高度可操作性的特点.     

基于本体的学科知识建模

学科知识建模是一项巨大的工程,当前存在的主要问题有知识库不能很好地共享和重用,难以实现语义上的推理及检索等.把本体技术应用于学科知识建模中,构造了部分课程本体,并实现了对该本体的推理及查询.     

信息抽取中领域本体建模方法研究

近几年来,本体作为一种知识重用、知识共享和建模的重要工具,尤其是领域本体,在信息抽取系统中扮演着越来越重要的角色。但是,目前领域本体的创建还缺乏系统的、工程化的方法。首先介绍了本体的概念及本体的建模准则,然后分析了现有的几种常见的本体建模方法,并通过对比分析各种方法的优缺点,再结合信息抽取的原理以及软件工程的思想,提出了一种新的领域本体的建模方法。该方法具有很强的逻辑性和可操作性,可被一些领域本体在建立时采用。     

面向对象的本体建模研究

UML语言是面向对象建模领域公认的工业标准,而本体建模是近来迅速发展的语义网中主要建模技术,UML在本体建模领域中的应用的可行性和具体方式一直是关注的焦点。该文对面向对象建模与本体建模之间的关系进行分析,基于UML本体承诺的概念,阐述了用UML对本体进行建模的本体对象建模的可行性,提出一种规范本体对象建模的UML元模型扩展方法,为UML直接对本体建模提供了理论依据。     

基于本体的设计知识建模研究

针对目前设计知识建模方法的不足,研究了基于本体的设计知识建模方法。本文给出了本体的定义、表示模型、设计知识的表达体系以及设计知识本体建模的方法,最后列出了基于Owl的设计知识本体表示的部分代码,以供同仁们研究参考。     

万维网基于本体云模型的信息建模方法

信息建模常用来表达知识,万维网分布式环境下,知识存在不确定性、不协调性、时变性和非恒常性,同时也有一定的群体性、规律性。为了更好的体现知识的性质,文章提出了一种基于本体云模型的信息建模方法。该方法使用本体云模型,并将本体云模型跟隶属云相结合,将隶属云作为概念的原子模型,本体云作为知识结构的原子模型,两者结合提供了从概念到领域知识一致的表达,通过该方法可以很好地进行万维网的信息建模。     

社会群体角色本体建模及其公理获取

提出社会群体角色本体的知识获取方法、建模方法和本体表示方法,包括社会群体、社会群体角色、社会群体角色动作、社会群体角色关系、社会群体角色关系公理等相关知识的获取方法。采用模板技术对社会群体角色本体进行建模,运用框架语言描述本体,实现社会群体角色本体中的公理获取及自动生成。     

化工企业DEVS仿真本体建模研究

化工过程运营与操作优化需要建模与仿真支持,传统仿真建模方法,无论机理建模或数据驱动建模,往往依赖建模者的经验知识和特定的仿真平台,模型的通用性和可扩展性差。本文结合本体技术和DEVS仿真建模理论,提出了一种基于本体映射的DEVS仿真建模方法。首先借助protege软件将化工生产过程知识抽象成领域本体,并构建DEVS模型本体作为模型范式结构用于存储模型知识;然后设计了基于SPARQL的本体映射方法,从节点、端口、连接三个角度出发实现领域本体到DEVS模型本体的映射,实现了知识的迁移;最后运用本体翻译技术将模型本体翻译到具体平台如C＋＋和java。文章通过化工生产仿真案例验证了该方法的可行性。     

一种基于领域本体的用户建模方法

针对当前大多数个性化服务系统的不足,以旅游领域为背景,提出了一种新的基于本体的用户模型构建方法,利用领域本体中的概念、实例和属性描述用户兴趣特征,实现了在语义层次上理解用户兴趣。实验表明,该方法能有效提高用户模型的质量。     

基于Ontology的建模方法

Ontology作为一种描述概念与概念之间关系的模型,能够解决知识共享和重用问题,近年来已被广泛应用于计算机科学的众多领域中,如数字图书馆、软件复用、Web异构信息的处理和语义Web等.介绍了Ontology的定义、分类及组成,并且介绍了建立本体的步骤,通过一个具体的实例详细阐述了建立本体的过程,最后给出了建立本体的构造图.     

Modeling Smart Grid neighborhoods with the ENERsip ontology

The electricity consumption in the buildings sector has been steadily increasing during the last decade, up to the point that energy efficiency in this sector has become a major problem for governments, utilities, customers, and the environment. The foreseen high penetration of distributed micro-generation facilities based on renewables can help to reduce the environmental footprint of buildings and households, although the complexity of managing effectively the electric grid increases dramatically under these conditions. The IEEE 2030 standard for interoperability in the Smart Grid remarks upon the importance of well-defined data models in such complex scenarios and puts emphasis on the benefits of ontologies and OWL (Web Ontology Language) for this purpose. This paper presents an OWL-based ontology that formally defines the vocabulary and taxonomy and captures the engineering and business semantics of this domain of knowledge (i.e., energy efficiency in the so-called nZEN – nearly Zero-Energy Neighborhoods). This ontology has been defined under the scope of the EU (European Union) research project ENERsip. The paper also highlights the main benefits the ontology brought to all the phases of the project life cycle, as well as how future work can make the most out of it.     

Extending the Unified Modeling Language for ontology development

There is rapidly growing momentum for web enabled agents that reason about and dynamically integrate the appropriate knowledge and services at run-time. The dynamic integration of knowledge and services depends on the existence of explicit declarative semantic models (ontologies). We have been building tools for ontology development based on the Unified Modeling Language (UML). This allows the many mature UML tools, models and expertise to be applied to knowledge representation systems, not only for visualizing complex ontologies but also for managing the ontology development process. UML has many features, such as profiles, global modularity and extension mechanisms that are not generally available in most ontology languages. However, ontology languages have some features that UML does not support. Our paper identifies the similarities and differences (with examples) between UML and the ontology languages RDF and DAML+OIL. To reconcile these differences, we propose a modification to the UML metamodel to address some of the most problematic differences. One of these is the ontological concept variously called a property, relation or predicate. This notion corresponds to the UML concepts of association and attribute. In ontology languages properties are first-class modeling elements, but UML associations and attributes are not first-class. Our proposal is backward-compatible with existing UML models while enhancing its viability for ontology modeling. While we have focused on RDF and DAML+OIL in our research and development activities, the same issues apply to many of the knowledge representation languages. This is especially the case for semantic network and concept graph approaches to knowledge representations. Initial sbmission: 16 February 2002 / Revised submission: 15 October 2002 Published online: 2 December 2002     

Modeling an ontology on accessible evacuation routes for emergencies

Providing alert communication in emergency situations is vital to reduce the number of victims. However, this is a challenging goal for researchers and professionals due to the diverse pool of prospective users, e.g. people with disabilities as well as other vulnerable groups. Moreover, in the event of an emergency situation, many people could become vulnerable because of exceptional circumstances such as stress, an unknown environment or even visual impairment (e.g. fire causing smoke). Within this scope, a crucial activity is to notify affected people about safe places and available evacuation routes. In order to address this need, we propose to extend an ontology, called SEMA4A (Simple EMergency Alert 4 [for] All), developed in a previous work for managing knowledge about accessibility guidelines, emergency situations and communication technologies. In this paper, we introduce a semi-automatic technique for knowledge acquisition and modeling on accessible evacuation routes. We introduce a use case to show applications of the ontology and conclude with an evaluation involving several experts in evacuation procedures.     

基于本体的林业领域文档特征权重模型

传统文档特征权重模型仅考虑关键词本身,文档内其他相关词汇并没有参与计算,信息检索时无法返回全面和准确的结果。为解决该问题提出了一种基于本体的林业领域文档特征权重模型。该模型计算TF-IDF特征权重;结合林业领域本体,分别获取关键词和林业领域内其他词汇的语义距离、语义重合度和概念的层次差,并计算语义相关度;结合TF-IDF和语义相似度的结果计算特征权重。实验证明该模型可以提高文本检索的查准率和查全率,使检索结果更加满足用户的需求。     

Modeling shallow marine carbonate depositional systems

Geological Process Models (GPMs) have been used in the past to simulate the distinctive stratigraphies formed in carbonate sediments, and to explore the interaction of controls that produce heterogeneity. Previous GPMs have only indirectly included the supersaturation of calcium carbonate in seawater, a key physicochemical control on carbonate production in reef and lagoon environments, by modifying production rates based on the distance from open marine sources. We here use the residence time of water in the lagoon and reef areas as a proxy for the supersaturation state of carbonate in a new process model, Carbonate GPM. Residence times in the model are calculated using a particle-tracking algorithm. Carbonate production is also controlled by water depth and wave power dissipation. Once deposited, sediment can be eroded, transported and re-deposited via both advective and diffusive processes. We show that using residence time as a control on production might explain the formation of non-ordered, three-dimensional carbonate stratigraphies by lateral shifts in the locus of carbonate deposition on timescales comparable to so-called 5th-order sea-level oscillations. We also show that representing supersaturation as a function of distance from open marine sources, as in previous models, cannot correctly predict the supersaturation distribution over a lagoon due to the intricacies of the flow regime.     

基于本体翻译的领域本体自动构建

手工构建本体是一项既费时又费力的工作,为解决此项工作的瓶颈问题,本体自动构建成为当前的一个研究热点和重点。考虑到不同语言描述的本体在本质上是相同的,只是表层的表示符号不同,提出了一种基于本体翻译的领域本体自动构建算法,该算法针对已存在本体中概念标签的不同情况,分别采用不同的统计指标来筛选标签的目标语翻译。通过将一个英文金融本体翻译成中文对算法进行了实验验证,说明了算法的有效性。     

Modeling and control of a single-phase marine cooling system

This paper presents two model-based control design approaches for a single-phase marine cooling system. Models are derived from first principles and aim at describing significant system dynamics including nonlinearities and transport delays, while keeping the model complexity low. The two approaches investigated are: a baseline design for performance comparison and a nonlinear robust control design. Performance and robustness of performance for the two control designs are evaluated through a simulation example. Both designs show good robustness towards parameter variations, while the nonlinear robust design performs better in terms of disturbance rejection.     

On ontology

A previously unpublished text by I. Kh. Shmain [On Ontology] written as a letter to V. B. Borshchev, a member of the editorial board of the collection NTI is presented below.     

本体中is-a层次的构建与本体集成

首先给出了本体中is-a层次的构建方法,并提出了is-a层次中删除概念的算法;其次,分析了本体集成的原因,给出了本体集成的分类、三种集成方式和四条集成原则;最后,提出一种基于OWL (Web ontology language)的本体集成算法,实验证明此算法可行.