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1.
朱创录 《甘肃科技》2010,26(4):42-44
语义Web的逻辑基础是描述逻辑,其出现的目的就是为了解决机器和人对知识理解的问题,因此,可以在语义Web的基础上展开推理。传统的推理系统结合语义Web可以克服知识表示方面的缺点,并且有利于知识的共享。探讨了OWL DL作为知识表示形式的优点;通过实例验证了OWL DL关于描述逻辑的推理。  相似文献   

2.
语义Web推理的研究与实现   总被引:1,自引:0,他引:1  
语义Web的逻辑基础是描述逻辑,语义Web出现的目的就是为了解决机器和人对知识理解的问题,因此可以在语义Web的基础上展开推理。传统的推理系统结合语义Web可以克服知识表示方面的缺点,并且有利于知识的共享。首先在语义Web的知识体系之上建立起来一套推理系统,然后通过应用实现对该系统进行了验证。  相似文献   

3.
基于描述逻辑的语义Web本体研究   总被引:1,自引:1,他引:1  
语义Web出现的目的就是为了解决机器和人对知识的理解的问题,首先需要解决的问题就是计算机对知识的理解问题,只有计算机理解了所建立的知识,才能在此基础上展开推理服务。首先讨论了传统知识表示方式的缺陷,然后对本体论的逻辑基础———描述逻辑进行了研究。由于OWLDL和描述逻辑的一致关系,因此使用OWLDL来表示本体。介绍了描述逻辑推理系统RACER。最后提出了解决本体层知识表示方法的解决方案。  相似文献   

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基于Topic Map的知识表示技术研究   总被引:1,自引:0,他引:1  
以Topic Map主题地图作为语义Web信息描述模型,阐述了Topic Map在Web资源组织中的作用和地位,研究了TM结构化知识表示向形式化逻辑的映射机制,以及基于TM的知识推理的实现.  相似文献   

6.
由语义网络语言的知识表示到谓词逻辑的转换   总被引:1,自引:0,他引:1  
语义网络作为表示知识的主要方法成为常识知识库组成的主要形式,从而引出知识库的维护及推理所要解决的问题。在研究中发现,将面向对象技术引入语义网络的研究,是目前的发展方向之一。特别地,对关系的继承属性的形式转换是本文所关注的。文章首先提出从语义网络到谓词逻辑这两种形式进行转换的基本操作,并给出由语义网络表示转换成谓词逻辑形式表示的算法。  相似文献   

7.
提出一种新的模糊逻辑数值模糊择优逻辑, 给出了数值模糊择优逻辑的语法和语义, 并研究了其性质. 该逻辑结合多值逻辑和择优推理的语义特点, 得到的推理关系具有模糊性、 次协调性和非单调性, 且知识的模糊性能以数值的形式显式地表现, 适用于对智能系统中的不精确、 不一致和不完备知识进行表示和推理.  相似文献   

8.
目的分析Ontology特点,探讨Ontology在自然语言理解中的应用。方法通过概念之间的关系来描述概念的语义。结果Ontology解决了自然语言理解中的消歧、推理问题和在语义Web中的应用。结论利用Ontology作为知识体进行自然语言理解,能够有效的把语言学知识和世界知识结合起来,运用世界知识对文本进行消歧和推理;Ontology与知识系统的知识库相融合,使得自然语言理解不仅仅是作为一种人机交互方式,而且能够与其它的基于知识的智能系统如专家系统整合。  相似文献   

9.
开放式信息抽取系统是从Web等非结构化文本中挖掘知识的主要途径,但其抽取结果往往存在大量噪声,对知识发现以及知识库构建产生较大影响。提出一种基于概率软逻辑模型的知识推理验证方法,该方法首先使用一阶逻辑语言对知识抽取结果进行转化和推理,并且在推理过程中引入本体规则进行约束,在此基础上,建立推理规则的自动学习机制,解除传统规则推理对于实体解析规则的依赖,进而实现对知识的自动推理和验证。经实验对比验证,该方法具有更优的算法性能,实现了规则的自动学习,提高了知识推理效率,对验证知识的语义规范性和正确性有积极作用。  相似文献   

10.
为了在语义网的构架中实现元数据的交互.针对一种特定的语义网——智能通信网,研究其推理机制.分析OWL DL语言的描述能力,在其蕴含的知识基础上建立Prolog推理规则,通过Visual Prolog逻辑编程实现了智能通信网的自动推理,并用实例验证该推理系统可完成知识库中元数据的交互,达到人机交互协同工作的要求.最后通过实验检测说明智能通信网推理系统与普通万维网相比,查准率更高.  相似文献   

11.
The discovery of the prolific Ordovician Red River reservoirs in 1995 in southeastern Saskatchewan was the catalyst for extensive exploration activity which resulted in the discovery of more than 15 new Red River pools. The best yields of Red River production to date have been from dolomite reservoirs. Understanding the processes of dolomitization is, therefore, crucial for the prediction of the connectivity, spatial distribution and heterogeneity of dolomite reservoirs.The Red River reservoirs in the Midale area consist of 3~4 thin dolomitized zones, with a total thickness of about 20 m, which occur at the top of the Yeoman Formation. Two types of replacement dolomite were recognized in the Red River reservoir: dolomitized burrow infills and dolomitized host matrix. The spatial distribution of dolomite suggests that burrowing organisms played an important role in facilitating the fluid flow in the backfilled sediments. This resulted in penecontemporaneous dolomitization of burrow infills by normal seawater. The dolomite in the host matrix is interpreted as having occurred at shallow burial by evaporitic seawater during precipitation of Lake Almar anhydrite that immediately overlies the Yeoman Formation. However, the low δ18O values of dolomited burrow infills (-5.9‰~ -7.8‰, PDB) and matrix dolomites (-6.6‰~ -8.1‰, avg. -7.4‰ PDB) compared to the estimated values for the late Ordovician marine dolomite could be attributed to modification and alteration of dolomite at higher temperatures during deeper burial, which could also be responsible for its 87Sr/86Sr ratios (0.7084~0.7088) that are higher than suggested for the late Ordovician seawaters (0.7078~0.7080). The trace amounts of saddle dolomite cement in the Red River carbonates are probably related to "cannibalization" of earlier replacement dolomite during the chemical compaction.  相似文献   

12.
AcomputergeneratorforrandomlylayeredstructuresYUJia shun1,2,HEZhen hua2(1.TheInstituteofGeologicalandNuclearSciences,NewZealand;2.StateKeyLaboratoryofOilandGasReservoirGeologyandExploitation,ChengduUniversityofTechnology,China)Abstract:Analgorithmisintrod…  相似文献   

13.
本文叙述了对海南岛及其毗邻大陆边缘白垩纪到第四纪地层岩石进行古地磁研究的全部工作过程。通过分析岩石中剩余磁矢量的磁偏角及磁倾角的变化,提出海南岛白垩纪以来经历的构造演化模式如下:早期伴随顺时针旋转而向南迁移,后期伴随逆时针转动并向北运移。联系该地区及邻区的地质、地球物理资料,对海南岛上述的构造地体运动提出以下认识:北部湾内早期有一拉张作用,主要是该作用使湾内地壳显著伸长减薄,形成北部湾盆地。从而导致了海南岛的早期构造运动,而海南岛后期的构造运动则主要是受南海海底扩张的影响。海南地体运动规律的阐明对于了解北部湾油气盆地的形成演化有重要的理论和实际意义。  相似文献   

14.
Various applications relevant to the exciton dynamics,such as the organic solar cell,the large-area organic light-emitting diodes and the thermoelectricity,are operating under temperature gradient.The potential abnormal behavior of the exicton dynamics driven by the temperature difference may affect the efficiency and performance of the corresponding devices.In the above situations,the exciton dynamics under temperature difference is mixed with  相似文献   

15.
The elongation method,originally proposed by Imamura was further developed for many years in our group.As a method towards O(N)with high efficiency and high accuracy for any dimensional systems.This treatment designed for one-dimensional(ID)polymers is now available for three-dimensional(3D)systems,but geometry optimization is now possible only for 1D-systems.As an approach toward post-Hartree-Fock,it was also extended to  相似文献   

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17.
The explosive growth of the Internet and database applications has driven database to be more scalable and available, and able to support on-line scaling without interrupting service. To support more client's queries without downtime and degrading the response time, more nodes have to be scaled up while the database is running. This paper presents the overview of scalable and available database that satisfies the above characteristics. And we propose a novel on-line scaling method. Our method improves the existing on-line scaling method for fast response time and higher throughputs. Our proposed method reduces unnecessary network use, i.e. , we decrease the number of data copy by reusing the backup data. Also, our on-line scaling operation can be processed parallel by selecting adequate nodes as new node. Our performance study shows that our method results in significant reduction in data copy time.  相似文献   

18.
R-Tree is a good structure for spatial searching. But in this indexing structure,either the sequence of nodes in the same level or sequence of traveling these nodes when queries are made is random. Since the possibility that the object appears in different MBR which have the same parents node is different, if we make the subnode who has the most possibility be traveled first, the time cost will be decreased in most of the cases. In some case, the possibility of a point belong to a rectangle will shows direct proportion with the size of the rectangle. But this conclusion is based on an assumption that the objects are symmetrically distributing in the area and this assumption is not always coming into existence. Now we found a more direct parameter to scale the possibility and made a little change on the structure of R-tree, to increase the possibility of founding the satisfying answer in the front sub trees. We names this structure probability based arranged R-tree (PBAR-tree).  相似文献   

19.
The geographic information service is enabled by the advancements in general Web service technology and the focused efforts of the OGC in defining XML-based Web GIS service. Based on these models, this paper addresses the issue of services chaining,the process of combining or pipelining results from several interoperable GIS Web Services to create a customized solution. This paper presents a mediated chaining architecture in which a specific service takes responsibility for performing the process that describes a service chain. We designed the Spatial Information Process Language (SIPL) for dynamic modeling and describing the service chain, also a prototype of the Spatial Information Process Execution Engine (SIPEE) is implemented for executing processes written in SIPL. Discussion of measures to improve the functionality and performance of such system will be included.  相似文献   

20.
Advances in wireless technologies and positioning technologies and spread of wireless devices, an interest in LBS (Location Based Service) is arising. To provide location based service, tracking data should have been stored in moving object database management system (called MODBMS) with proper policies and managed efficiently. So the methods which acquire the location information at regular time intervals then, store and manage have been studied. In this paper, we suggest tracking data management techniques using topology that is corresponding to the moving path of moving object. In our techniques, we update the MODBMS when moving object arrived at a street intersection or a curved road which is represented as the node in topology and predict the location at past and future with attribute of topology and linear function. In this technique, location data that are corresponding to the node in topology are stored, thus reduce the number of update and amount of data. Also in case predicting the location,because topology are used as well as existing location information, accuracy for prediction is increased than applying linear function or spline function.  相似文献   

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