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1.
闫俊伢 《实验室科学》2012,15(4):102-106
统一建模语言(UML)融入了软件工程领域的新思想、新方法和新技术,以UML的图形符号为基础,采用图形符号来描述系统的模型视图。以机房管理信息系统为例,阐述UML建模分析技术在机房管理系统中的应用,描述如何使用UML进行建模分析和开发的具体过程,分析在开发过程中经常出现的问题以及解决方案,并对统一建模语言UML中的用例图、时序图、协作图及建模技术的应用效果进行了深入研究。  相似文献   

2.
曲培娟 《甘肃科技》2007,23(1):123-125
目前工作流建模方法又很多,但不可通用;而UML是一种标准的可视化建模语言。使用UML对工作流过程建模,可以易于理解和使用。UML活动图可以很好地分析和描述工作流建模的动态机制,可以有效地分析工作流建模过程。通过一个实例,分析了UML活动图在工作流建模中的应用。  相似文献   

3.
UML扩展机制在嵌入式实时建模中的应用   总被引:1,自引:0,他引:1  
段盛 《科学技术与工程》2007,7(6):1012-1014
在嵌入式实时系统建模中,针对UML没有专门的图来描述实时性,对时间约束的建模能力不强的情况,提出了一种使用UML扩展机制进行嵌入式实时系统建模的方法,并介绍了该方法的一个应用实例。  相似文献   

4.
MPLS在虚拟专用网中的应用   总被引:3,自引:0,他引:3  
首先阐述了虚拟专用网(VPN)和多协议标记交换(MPLS)技术的概念,又描述了MPLS协议在虚拟专用网建设中的应用。主要就MPLS技术应用于虚拟专用网的优势、MPLSVPN的网络结构、内部机制、工作过程及其完全性做了论述。  相似文献   

5.
论述了工作流元模型的三维性,在采用UML2.0活动图的新特性后,提出了一个基于UML2.0活动图的工作流模型,定义了此模型的形式化和非形式化描述方法,并指出了其建模规则,为探询UML2.0活动图在工作流模型描述方法中应用做了初步尝试.  相似文献   

6.
从图元所描述的内容入手研究了UML的静态建模机制和动态建模机制.分析了UML建模的优势.提出了UML建模的六大主要特点.在此基础之上基于UML对客户关系管理中营销管理子系统进行流程建模,构建了营销管理子系统的功能关系图,建立了相关的用例图、类图和动态图.  相似文献   

7.
应用扩充UML元模型定义企业建模,建立企业工作流视图、功能视图和信息视图.工作流建模,采用状态机(state machine)描述业务流程;功能建模,采用用例图(Use Case diagram)表达功能需求;信息建模,采用类图(class diagram)建立逻辑模型.建立了一个典型的离散型制造企业的企业模型,实现了相应的应用软件框架及动态企业建模在生产管理中的应用.  相似文献   

8.
UML的建模过程及在空管系统需求分析中的应用   总被引:3,自引:0,他引:3  
UML是一种面向对象的可视化建模语言,通过不同的模型从不同的角度对系统的需求分析建模。描述了UML的建模过程及其在空管系统需求分析中的应用。  相似文献   

9.
总结了UML 2.0活动图新特性,定义了一个基于UML 2.0活动图的工作流模型的形式化描述方法,并提出其基本控制流模式和建模规则.最后用一个应用实例来演示基于UML2.0活动图的工作流模型。  相似文献   

10.
从UML类图到本体的自动映射   总被引:2,自引:0,他引:2  
严璐  李利 《科学技术与工程》2008,8(13):3645-3649
本体(ontology)是描述概念及概念之间关系的概念模型,通过概念之间的关系来描述概念的语义.然而,本体的描述语言种类繁多,阅读困难,不利于本体建模人员交流沟通.UML作为建模领域的公认标准,已被许多人熟知和广泛使用.基于UML和本体建模的相似性,提出利用UML类图描述本体模型,并建立了从UML类图到本体模型的自动映射,以提高本体建模的效率.  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.
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   

13.
There are numerous geometric objects stored in the spatial databases. An importance function in a spatial database is that users can browse the geometric objects as a map efficiently. Thus the spatial database should display the geometric objects users concern about swiftly onto the display window. This process includes two operations:retrieve data from database and then draw them onto screen. Accordingly, to improve the efficiency, we should try to reduce time of both retrieving object and displaying them. The former can be achieved with the aid of spatial index such as R-tree, the latter require to simplify the objects. Simplification means that objects are shown with sufficient but not with unnecessary detail which depend on the scale of browse. So the major problem is how to retrieve data at different detail level efficiently. This paper introduces the implementation of a multi-scale index in the spatial database SISP (Spatial Information Shared Platform) which is generalized from R-tree. The difference between the generalization and the R-tree lies on two facets: One is that every node and geometric object in the generalization is assigned with a importance value which denote the importance of them, and every vertex in the objects are assigned with a importance value,too. The importance value can be use to decide which data should be retrieve from disk in a query. The other difference is that geometric objects in the generalization are divided into one or more sub-blocks, and vertexes are total ordered by their importance value. With the help of the generalized R-tree, one can easily retrieve data at different detail levels.Some experiments are performed on real-life data to evaluate the performance of solutions that separately use normal spatial index and multi-scale spatial index. The results show that the solution using multi-scale index in SISP is satisfying.  相似文献   

14.
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   

15.
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   

16.
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   

17.
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   

18.
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   

19.
In the 19th century the society was controlled by men, and women were just appendants of them, they had not any rights and freedom. But Jane was an exception, she showed some characteristics of early feminist. Jane showed her characteristics of feminism in three aspects: rebellion, equality, and independence. These characteristics were helpful to her success, and feminism is the only way out for women of that time.  相似文献   

20.
The non-orthogonal localized molecular orbital(NOLMO)is the most localized representation of electronic degrees of freedom.As such,NOLMOs are thus potentially the most efficient for linear scaling calculations of electronic structures for large systems.However,direct ab initio calculations with NOLMO have not been fully implemented and widely used,partly because of the slow convergence issue in the optimization of NOLMO.We devel-  相似文献   

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