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1.
第五代计累机是智能计算机系统,它是以处理知识为目标的,知识库是它的关键环节之一,所以知识库系统的研究引起了广泛的兴趣。本文通过数据库,知识库和PROLOG程序之间的对比,阐明了PROLOG程序具有知识库系统的基本功能,认为在PROLOG语言的基础上开发知识库系统是可行的。  相似文献   

2.
一、引言逻辑程序设计语言 PROLOG 是一种描述性语言,用户只需将问题求解所需的知识以子句形式提交系统,系统依靠自身的演绎求解机制可根据用户提供的知识求解出用户期望的结果。正因为如此,PROLOG 求解机制对用户查询的处理效率就成了构造实用 PROLOG 系统  相似文献   

3.
PROLOG语言曾被日本选作第五代机的核心语言,至今仍是AI研究领域中很活跃的一部分。本文立足于实践,对PROLOG中很重要的库操作谓词retract的语义进行了扩充,并阐明了扩充后PROLOG系统的实现思想。  相似文献   

4.
本文介绍了一个分布式知识库系统DKBS/TH—1的结构模型。它以PROLOG作为推理工具,Unify关系数据库系统作为存放知识的机构,二者之间通过一阶谓词逻辑的子集Horn子句进行联系.分布式系统中各结点之间的通讯联系也由Horn子句来实现,本文还讨论了PROLOG与关系数据库的结合方法及查询优化的技术.  相似文献   

5.
本文首先介绍了PROLOG检测工具的研究现状,作者针对PROLOG语言的特点,提出了一种对PROLOG进行矛盾检测的算法,并用Turbo C语言实现了该算法,该算法作为一种PROLOG检测工具已被合并到Rurbo PROLOG系统盘中。  相似文献   

6.
提出一种基于PROLOG扩充不确定性处理能力的逻辑程序设计语言EXLOGL,并介绍了该语言解释系统的总体结构、知识库设计及演绎求解原理.  相似文献   

7.
本文试从谓词公式简化后的PROLOG子句标记法和归结的意义出发,讨论用PROLOG实现定理证明的方法.主要内容包括:谓词公式的简化及其PROLOG形式表示;归结与定理证明的思想;用PROLOG证明定理的方法.  相似文献   

8.
基于一阶谓词逻辑的PROLOG语言不允许量词作用于谓词,这限制了它的表达和处理范围。本文提出了两种PROLOG(间接)处理高阶谓词的方法,即“公用谓词”方法和“附加子目标”方法。  相似文献   

9.
本文是对冠状动脉硬化性心脏病进行诊断与治疗的一个医学专家系统,(仅对原发性心脏停搏,心绞痛和心肌梗塞三种疾病进行处理)主要分为五大部分:知识库、推理机、解释系统、知识获取部分、数据库。为了使信息处理比较细致,我们对模糊性问题进行了精确化处理,对推理机方面采用了正向推理与反向推理交叉使用的混合的模糊推理。为了使医生的经验描述准确,我们采用了可信度推算使其精确化,同时为了使用方便,也为了解决中文的语义的多义性以及假定使用本软件的医务人员不懂PROLOG语言和序设计(本程序采用PROLOG语言)  相似文献   

10.
肺心病早期无创性诊断专家系统   总被引:1,自引:0,他引:1  
用PROLOG实现的分类专家系统,着重介绍了知识的获取、知识库的结构及其推理机制。系统用产生式规则表示知识,采用正向推理策略,较准确地模拟了专家的施治过程。  相似文献   

11.
Language markedness is a common phenomenon in languages, and is reflected from hearing, vision and sense, i.e. the variation in the three aspects such as phonology, morphology and semantics. This paper focuses on the interpretation of markedness in language use following the three perspectives, i.e. pragmatic interpretation, psychological interpretation and cognitive interpretation, with an aim to define the function of markedness.  相似文献   

12.
The Williston Basin is a significant petroleum province, containing oil production zones that include the Middle Cambrian to Lower Ordovician, Upper Ordovician, Middle Devonian, Upper Devonian and Mississippian and within the Jurassic and Cretaceous. The oils of the Williston Basin exhibit a wide range of geochemical characteristics defined as "oil families", although the geochemical signature of the Cambrian Deadwood Formation and Lower Ordovician Winnipeg reservoired oils does not match any "oil family". Despite their close stratigraphic proximity, it is evident that the oils of the Lower Palaeozoic within the Williston Basin are distinct. This suggests the presence of a new "oil family" within the Williston Basin. Diagnostic geochemical signatures occur in the gasoline range chromatograms, within saturate fraction gas chromatograms and biomarker fingerprints. However, some of the established criteria and cross-plots that are currently used to segregate oils into distinct genetic families within the basin do not always meet with success, particularly when applied to the Lower Palaeozoic oils of the Deadwood and Winnipeg Formation.  相似文献   

13.
王慧 《科技信息》2008,(10):240-240
Wuthering Heights, Emily Bronte's only novel, was published in December of 1847 under the pseudonym Ellis Bell. The book did not gain immediate success, but it is now thought one of the finest novels in the English language. Catherine is the key character of this masterpiece, because everybody and everything center on her though she had a short life. We can understand this masterpiece better if we know Catherine well.  相似文献   

14.
何延凌 《科技信息》2008,(4):258-258
Language is a means of verbal communication. People use language to communicate with each other. In the society, no two speakers are exactly alike in the way of speaking. Some differences are due to age, gender, statue and personality. Above all, gender is one of the obvious reasons. The writer of this paper tries to describe the features of women's language from these perspectives: pronunciation, intonation, diction, subjects, grammar and discourse. From the discussion of the features of women's language, more attention should be paid to language use in social context. What's more, the linguistic phenomena in a speaking community can be understood more thoroughly.  相似文献   

15.
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   

16.
Location based services is promising due to its novel working style and contents.A software platform is proposed to provide application programs of typical location based services and support new applications developing efficiently. The analysis shows that this scheme is easy implemented, low cost and adapt to all kinds of mobile nework system.  相似文献   

17.
以AC-13级配为基础,将橡胶颗粒代替部分集料掺入混合料中,以低温弯曲试验为评价方法对不同橡胶颗粒掺量下沥青混合料的低温抗裂性进行研究,并引入应变能密度值对混合料的低温抗裂性进行综合评价.试验结果表明:橡胶颗粒沥青混合料试件的破坏微应变均超过2 300,满足冬寒区的技术指标;无论是否掺加橡胶颗粒,随着温度的下降,沥青混合料破坏时的最大弯拉强度增大,弯拉应变降低,劲度模量增大;弯曲应变能密度在胶粒掺量为1%左右时具有较大的弯曲应变能密度值,此时橡胶颗粒沥青混合料具有较好的低温抗裂性.  相似文献   

18.
理论推导与室内实验相结合,建立了低渗透非均质砂岩油藏启动压力梯度确定方法。首先借助油藏流场与电场相似的原理,推导了非均质砂岩油藏启动压力梯度计算公式。其次基于稳定流实验方法,建立了非均质砂岩油藏启动压力梯度测试方法。结果表明:低渗透非均质砂岩油藏的启动压力梯度确定遵循两个等效原则。平面非均质油藏的启动压力梯度等于各级渗透率段的启动压力梯度关于长度的加权平均;纵向非均质油藏的启动压力梯度等于各渗透率层的启动压力梯度关于渗透率与渗流面积乘积的加权平均。研究成果可用于有效指导低渗透非均质砂岩油藏的合理井距确定,促进该类油藏的高效开发。  相似文献   

19.
As an American modern novelist who were famous in the literary world, Hemingway was not a person who always followed the trend but a sharp observer. At the same time, he was a tragedy maestro, he paid great attention on existence, fate and end-result. The dramatis personae's tragedy of his works was an extreme limit by all means tragedy on the meaning of fearless challenge that failed. The beauty of tragedy was not produced on the destruction of life, but now this kind of value was in the impact activity. They performed for the reader about the tragedy on challenging for the limit and the death.  相似文献   

20.
Quality traits in wheat (Triticum aestirum L.) were studied by quantitative trait locus (QTL) analysis in a recombinant inbred line (RIL) population, a set of 131 lines derived from Chuan 35050 × Shannong 483 cross (ChSh). Grains from RILs were assayed for 21 quality traits related to protein and starch. A total of 35 putative QTLs for 19 traits with a single QTL explaining 7.99-40.52% of phenotypic variations were detected on 10 chromosomes, 1D, 2A, 2D, 3B, 3D, 5A, 6A, 6B, 6D, and 7B. The additive effects of 30 QTLs were positive, contributed by Chuan 35050, the remaining 5 QTLs were negative with the additive effect contributed by Shannong 483. For protein traits, 15 QTLs were obtained and most of them were located on chromosomes 1 D, 3B and 6D, while 20 QTLs for starch traits were detected and most of them were located on chromosomes 3D, 6B and 7B. Only 7 QTLs for protein and starch traits were co-located in three regions on chromosomes 1D, 2A and 2D. These protein and starch trait QTLs showed a distinct distribution pattern in certain regions and chromosomes. Twenty-two QTLs were clustered in 6 regions of 5 chromosomes. Two QTL clusters for protein traits were located on chromosomes 1D and 3B, respectively, three clusters for starch traits on chromosomes 3D, 6B and 7B, and one cluster including protein and starch traits on chromosome 1D.  相似文献   

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