结构化面向对象形式规格说明语言OOZS——应用实例

ＯＯＺＳ是一种面向对象的形式规格说明语言,它是Ｚ规格说明语言的一种面向对象扩展,本文结合一个四边形图形的例子对ＯＯＺＳ语言的应用进行说明。     

结构化面向对象形成规格说明语言OOZS：设计原理

形式方法与面向对象方法的综合使用可以使它们各自的优点得 到充分体现;形式方法全目标软件系统的需求规格说明简明、精,精确,面向对象方法使目标软件系统的组织和分解工作更加系统、自然。     

结构化面向对象形式规格说明语言OOZS——类型检查器

ＯＯＺＳ类型检查器是ＯＯＺＳ规格说明的一种检查程序,它可以找出用户编写的ＯＯＺＳ规格说明中出现的语法错误以及类型操作的不一致错误,并能够自动定位错误．本文介绍了ＯＯＺＳ类型检查器的设计与实现．     

需求分析的 Z 语言形式化方法

非形式化的需求规格说明容易产生歧义,导致所开发的软件系统不能满足用户的功能要求.Z语言是一种基于集合和一阶谓词逻辑的模式规约语言,可用于产生精确的需求规格说明.介绍了需求分析的Z语言形式化方法,并给出了一个通用堆栈的Z语言描述实例,同时指出这种形式化方法有待进一步研究的地方.     

结构化面向对象形态规格说明语言OOZS：类型检查器

ＯＯＺＳ类型检查器是ＯＯＺＳ规格说明的一种检查程序,它可以找出用户编写的ＯＯＺＳ规格说明中出现的语法错误以及类型操作的不一致错误,并能够自动定位错误,本文介绍了ＯＯＺＳ类型检查器的设计与实现。     

面向对象的程序语言的概念在Simula,Smalltalk及C++中的应用

面向对象的方法是下一代语言中最有前途的方法之。面向对象的程序语言介绍了程序语言领域中许多新概念以及有用的概念。在这篇文章中,研究了三种主要的ＯＯＰＬｓ：Ｓｉｍｕｌａ,Ｓｍａｌｌｔａｌｋ和Ｃ＋＋,Ｓｉｍｕｌａ是最早的ＯＯＰＬ．（ｏｖｅｒｌｏａｄｉｎｇ）等都是Ｓｍａｌｌｔａｌｋ对ＯＯＰＬｓ的发展所做的贡献。Ｃ＋＋是第一个被广泛采用的ＯＯＰＬ,是因为Ｃ＋＋是Ｃ语言的高级形式,而Ｃ语言又是目前最通用的程序     

对象式软件需求定义及其自动转换的研究

在面向对象构架之下研究了软件需求定义及其自动转换问题,提出了层次化对象式软件需求模型ＮＤＨＯＲＭ;定义了图形化对象式需求定义语言ＮＤＯＲＬ;探讨了从半形式需求定义到形式功能规约的转换技术;介绍了对象式软件需求分析支撑系统ＮＤＯＲＡＳＳ的设计与实现,该系统支持用户借助ＭＮＤＨＯＲＭ模型及ＮＤＯＲＬ语言来构件软件需求定义,并实现到形式功能规约ＯＯＺＥ的自动转换。     

一种在万维网上显示Z规格说明的方法

万维网的普及和发展给软件工程师提供了交流和共享知识的场所。Ｚ是一种基于一阶谓词逻辑和集合论的形式规格说明语言,Ｚ语言用大量的数学符号和模式来构造规格说明,然而,当前的ＨＴＭＬ标准不支持在万维网上显示Ｚ规格说明所需的一些符号,此外如何在ＨＴＭＬ文件中表示模式框、公理框和类描述同样是困难的,本文实现了一种在万维网上显示Ｚ规格说明的解决方法,并给出了程序代码和实例。     

基于规格说明的面向对象软件原型开发

提出一种基于规格说明的面向对象软件原型开发方法，规格说明分为结构部分和行为部分。结果部分利用面向对象开发方法ＯＭＴ的直观可社的表示和分析设计规程；行为部分利用类ＣＣＳ的表示文和形式验证机制，使得规格说明及其求精结果由一致的语言表示，且在同一的形式框架构成的原型上进行持为分析。     

结构化面向对象形式规格说明语言OOZS——规格说明测试

自动或半自动实现面向对象形式规格说明的测试不但要求相应的规格说明语言具有严格的形式语义,而且要求使用人员具有较深的数学基础,从而最终影响了面向对象规格说明测试的研究。本文提出了一种测试方法,该方法通过构造测试用例对面向对象形式规格说明的各种特性进行检验,可以较容易地发现形式规格说明中的不一致、不完整之处。     

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.     

Characterization of Ordovician carbonate reservoirs, southeastern Saskatchewan, Canada

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.     

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.     

A computer generator for randomly layered structures

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

An Index mechanism for multi-scale view in spatial databases

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.     

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     

On the Thermodynamic Limit for Responses to Static Electromagnetic Fields

For molecular systems,the quantum-mechanical treatment of their responses to static electromagnetic fields usually employs a scalar-potential treatment of the electric field and a vector-potential treatment of the magnetic field.Although the potential for each field separately is associated with the choice of an(unphysical)origin,the precise choice of the origin for the electrostatic field has little consequences for the results.This is different for the