基于XML的Use Case复用

提出了一种基于XML的Use Cax的复用方法，采用XML的形式描述Use Case，然后在此基础上进行Use Case的查询和复用。由于Use Case是在软件开发的分析设计阶段的软件产物，因此对其进行的复用是一种较高抽象级别的软件知识复用，能够较大地提高软件开发过程中的复用水平．     

基于Use Case的需求建模实践

需求分析是软件工程中至关重要的步骤之一,而Use Case是进行需求分析的重要建模工具．利用Use Case进行需求建模分析,不仅思路清晰,而且容易理解和跟踪,所以日益受到软件设计工程师的青睐,首先阐述Use Case的基本概念和基本特征,然后提出了一种基于Use Case的需求建模方法,并通过一个实例详细讲解了此方法在建模中的廊用,最后总结了在建模过程中需要注意的事项。     

利用Power Designer建立Use Case图

介绍了标准的、面向对象的图形化建模语言UML和如何利用Power Designer建立Use Case图。     

UML在电子商务系统中的业务建模应用

电子商务的发展方兴未艾,相关产业的营销目前正处在从传统型向电子商务转化阶段,转变过程中需要应用和集成最新的信息技术,以达到对网络信息资源最有效地利用和共享.统一建模语言UML是一种定义良好,易于表达,功能强大且适用广泛的建模语言.业务模型关注系统针对的业务,并不是每个项目都需要业务模型,但是有时业务模型的作用很大.在利用UML建立电子商务系统模型和开发软件系统时,首要任务就是建立系统的业务模型.该文以电子商务系统(E-Commerce)为例详细论述了Use Case 以及如何运用正确的Use Case 建立系统业务模型的方法.     

基于UML的教学管理系统分析与设计

针对高校教学管理系统软件项目开发需求,基于UML建立了主要的系统静态结构模型与动态行为模型.对与新学期的课程选课注册管理与学生成绩管理两项工作给出详尽的分析和设计,如系统边界、活动者、Use Case、对象类图、用户接口及数据库模型.依据校园网,给出分布式系统客户/服务器结构的组件图及配置图.     

基于UML的动态企业建模的研究与实现

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．     

A components library system model and the support tool

Component-based development needs a well-designed components library and a set of support tools. This paper presents the design and implementation of a components library system model and its support tool UMLCASE. A set of practical CASE tools is constructed. UMLCASE can use UML to design Use Case Diagram. Class Diagram etc. And it integrates with components library system.     

心理与教育元分析中相关系数的范围限制矫正

介绍了如何利用矫正公式在元分析中对相关系数的范围限制进行矫正.CaseⅠ和CaseⅡ针对直接范围限制,而CaseⅢ、CaseⅣ和CaseⅤ针对间接范围限制.由于条件较难满足CaseⅠ和CaseⅢ很少被使用,CaseⅡ则是早期运用最多的矫正公式.因现实研究多数为间接范围限制,针对直接范围限制的CaseⅡ会低估相关系数真实值,这种情况下CaseⅣ和CaseⅤ比CaseⅡ准确.CaseⅣ和CaseⅤ也有弱点,CaseⅣ的核心假设,即第三方变量S对效标变量P的影响全部由预测变量T中介,通常无法满足,而当预测变量和效标变量的相关接近0时,就难以选择CaseⅤ的矫正公式.     

SOFC/MGT混合发电系统变工况控制模式及性能分析

以220kW的SOFC/MGT混合发电系统为研究对象,建立了相应的数学模型,分析了不同控制模式对混合发电系统变工况性能的影响.结果表明:对于220kW的SOFC/MGT混合发电系统,在单独SOFC燃料控制模式(Case 1)下,系统的稳定负荷必须大于70%;在变转速控制模式(Case 2)下,系统的稳定负荷必须大于77%;而在定转速恒定电池温度的控制模式(Case3)下,系统最低负荷可以低到59%.在相同负荷条件下,Case 2对应的系统效率最高,Case 1对应的系统效率最低.为保证混合发电系统的高效率,并扩大混合发电系统的运行范围,提出了一种新的控制模式,可以使得混合发电系统最低负荷达到45%,而系统效率始终保持在56.4%以上.     

软件危机与软件工程简介

本文介绍了软件危机和软件工程的概念以及解决软件危机的方法Case技术。     

Markedness and its Interpretation in Language Use

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.     

Features of Women's language

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.     

An Analysis of Catherine＇s Character——Wuthering Heights

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.     

Lower Paleozoic oil relationships within Williston Basin, Canada

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.     

低渗透非均质砂岩油藏启动压力梯度研究

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。     

On Tragic Consciousness In The Works By Ernest Hemingway

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.     

Design and analysis of generic LBS application developing platform

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.     

Achieving Unusual States of Matter Under High Pressure

正The periodicity of the elements and the non-reactivity of the inner-shell electrons are two related principles of chemistry,rooted in the atomic shell structure.Within compounds,Group I elements,for example,invariably assume the+1 oxidation state,and their chemical properties differ completely from those of the p-block elements.These general rules govern our understanding of chemical structures and reactions.Using first principles calcula-     

Exchange-Correlation and Electronic Excitation Energies from Pairing Matrix Fluctuations

We have developed an adiabatic connection to formulate the ground-state exchange-correlation energy in terms of pairing matrix linear fluctuations.This formulation of the exchange-correlation energy opens a new channel for density functional approximations based on the many-body perturbation theory.We illustrate the potential of such approaches with an approximation based on the particle-particle Random Phase Approximation(pp-RPA).This re-     

Density Functional Theory for the Response of Periodic Systems to Electric Fields Based on the Vector Potential Approach

正The electronic and nuclear(structural/vibrational)response of 1D-3D nanoscale systems to electric fields gives rise to a host of optical,mechanical,spectral,etc.properties that are of high theoretical and applied interest.Due to the computational difficulty of treating such large systems it is convenient to model them as infinite and periodic(at least,in first approximation).The fundamental theoretical/computational problem in doing so is that