AOSD方法及其在分布式系统开发中的应用

在包含诸多横切关注点的复杂软件系统开发中，面向对象软件开发方法（OOSD）存在无法克服的缺陷。在分析面向对象软件开发方法对横切关注点处理的缺陷的基础上，讨论了面向方面软件开发（aspect-oriented software development，AOSD）方法及其在复杂系统开发中的优越性，提出了一种面向方面软件开发方法的过程模型，介绍了面向方面软件开发方法在分布式系统开发中的应用。     

领域分析在C3I仿真测试环境中的应用

领域分析和建模广泛应用于大型软件系统的分析和设计。目前，由于缺乏有效的方法和实验途径，在C^3I系统的建模和设计过程中难以快速建立系统原型，给实际的开发造成了不便。该文将领域技术应用于C^3I仿真测试环境中，从四个紧密相关的不同视点（环境、交互、焦点分析和整体分析）来对系统进行领域分析和建模，介绍和说明了它们的界定范围、表示内容、使用方法以及在领域分析中的作用，并从这四个方面来分析和描述了C^3I仿真测试环境领域模型的分析和设计过程。该仿真测试环境的领域模型已经应用于实践中，指导了某C^3I系统的开发和研制。     

海运物流自动订舱系统的EFSM建模与实现

自动订舱系统是一类控制条件复杂的状态变化自动处理系统，精确的系统建模是系统成功的关键，文中首先介绍了海运物流自动订舱系统的特征及相关建模技术，提出了一种扩展有限状态机（EFSM）的建模方法，分析了该建模技术的方法，图素，语义以及模型到算法的一种映射关系。最后利用这种形式化建模技术实现了海运物流自动定舱系统，给出的系统建模和实现方法可以运用到各类电子化申请／答复的的系统设计中。     

着色Petri网及其在系统建模与仿真中的应用

在众多的系统建模方法和语言中,用着色Petri网（Colored Petri Net,简写CPN）建立的模型是可执行的,更有利于动态仿真,非常适合建模具有同步、并发、资源共享的大系统。文章介绍了CPN的基本概念及建模特性,阐明了CPN的实用价值及应用发展前景,并对一个军事系统一一空对空导弹攻击系统进行CPN的图形形式的建模分析,并用Design/CPN进行仿真验证。     

基于面向方面MDA的软件开发方法

软件系统通常有许多横切整个系统的非功能需求,仅采用面向对象的方法不能很好的处理这些横切关注点.软件开发中使用面向方面MDA的方法,在设计阶段将系统的非功能需求从功能需求中分离出来,通过扩展UML建立面向方面PIM元模型和基于AspcctJ的PSM元模型,横切关注点和核心业务逻辑就可以根据这些元模型分别建模,从而形成面向方面PIM和PSM,然后将系统PSM转换成系统代码.这种方法降低了软件开发的复杂性,提高了系统的可重用性、可维护性和横切关注点的模块化程度,最后给出了应用实例.     

基于图文法的并发系统状态测试方法及其实现

在并发系统的研究和开发中，迫切需要一种能正确有效地描述并发系统的动态进程互联结构、动态进程通信和进程演化行为的形式化方法以及基于这种形式化方法的并发系统动态状态的测试手段．本文介绍一种基于图文法模型的并发系统状态测试方法，该方法与描述并发系统结构和行为的图文法模型相结合，构成了一个并发系统开发支持环境．这一方法可根据对并发系统的状态测试要求，在并发系统的运行期自动跟踪和记录并发系统的运行状态和通信情况，使并发系统的开发者可以实时地得到并发系统的运行状态，或者在并发系统运行结束后重演并发系统的状态变化过程.     

基于隐马尔可夫模型的软件状态评估预测方法

随着软件系统功能和性能的强化和提高,企业的管理效率在不断提升,运营模式也越来越丰富.与此同时,软件系统变得越来越复杂,这向软件系统管理和维护提出了严峻的挑战.如何通过采集系统外部特征参数,对系统内部状态进行客观、准确地评估和预测,成为亟待解决的问题.为此,提出了一种基于隐马尔可夫模型的软件系统状态评估预测方法.该方法基于软件系统外在特征参数,通过K-means方法构建系统的观测状态,并以此建立隐马尔可夫模型,建立起系统外在状态（观测状态）和内部状态（隐藏状态）之间的联系;再利用三次指数平滑法对具有周期性变化的系统特征参数进行预测,即可预测系统未来状态.针对基于B/S软件架构的信息管理系统的实验,其结果表明该方法对系统状态评估和预测具有较高的准确性.     

基于主模型的协同设计软件架构技术研究

运载火箭总体方案论证过程中,由于涉及专业多、专业间迭代交互频繁、设计方案多变等特点,容易造成多专业协同设计时版本与技术状态的不统一,需要研究针对运载火箭产品的通用建模方法,并开发相应的软件系统;基于统一数据源的协同设计理念,结合运载火箭总体设计与数据模型特点,通过定义基础信息模型、概念模型、参数模型、外部定义模型4种数据模型,提出了针对运载火箭产品的通用主模型构建方法;将此通用建模方法软件化,搭建了基于主模型的协同设计软件系统整体架构;此架构包含主模型管理系统、主模型建模工具及应用客户端三部分,实现了多专业协同设计过程中数据与版本的统一管理、技术状态一致性分析、谱系追踪、数据展示与应用等功能;该主模型建模工具与客户端软件系统的实现,为运载火箭的总体协同设计提供了工具支撑。     

基于反馈神经网络的动态化工过程建模

针对非线性动态化工过程建模存在的问题,提出了一种新的反馈神经网络结构,并将状态反馈、时间序列延尺以及集中节点的概念结合起来,用于提高反馈神经网络的性能,同时又使得网络结构不至于太复杂,在用此网络结构建模的时间,成功地将BP算法用一网络模型的训练。文中将这种反馈神经网络结构分别对一个单输入单输出（SISO）的非线笥动态系统和一个多输入单输出（SIMO）的连续全混釜（CSTR）模型进行建模,并将所得模型与基于表态BP神经神经所得的模型在模型输出精度和抗干扰性等方面进行了比较,证明了该反馈神经在动态过程建模中能够比静态BP模型更好地反映出动态过程的输入输出关系,并具有一定的抗干扰能力。     

AOP及其编织技术的研究

AOP（Aspect Oriented Programming）是一种新的编程技术，它为开发者提供了一种描述横切关注点的机制，并能够自动将横切关注点编织到面向对象的软件系统中，从而实现了横切关注点的模块化，通过划分方面代码，横切关注点变得容易处理。介绍了AOP框架中经常出现的概念和AO软件的开发过程，着重讨论了当前比较流行的几种编织技术并阐述了这几种编织技术各自的优缺点。     

一种基于CSP的面向方面状态图形式化描述方法

面向方面通过分离关注点解决软件系统中的横切问题,通过扩展UML可实现对面向方面的建模。本文利用UML的扩展机制将方面加入状态图中,描述了状态图中的方面与核心组件以及方面之间的编织,然后利用进程代数的形式化语义描述了扩展后的UML状态图,克服了扩展UML描述状态图的缺乏形式化动态语义,不利于对模型进行形式化验证和证明的缺
点。最后,以ATM自动取款机为例验证了基于CSP的面向方面状态图形式化描述的有效性。     

基于 UML扩展的面向方面建模 *

面向方面编程 ( AOP)把横切关注点从系统中分离 ,解决了面向对象编程 ( OOP)中代码纠缠、散射的问题。但在面向方面建模中 ,横切方面没有得到很好的支持。首先 ,在统一建模语言 ( UML)元模型的基础上利用类图建立了整体框架模型 ,设计了核心类、方面、横切元素及其之间的关系 ;其次 ,利用 UML扩展机制为切点、通知、方面等主要元素建立了新的模型 ,设计了它们与方面之间新的关联关系并为其定义了语义。通过 UML扩展,使得 UML能够直接表达面向方面概念 ,支持面向方面建模设计 ,实现了面向方面模型     

基于 UML扩展的面向方面建模 *

面向方面编程（AOP）把横切关注点从系统中分离,解决了面向对象编程（OOP）中代码纠缠、散射的问题。但在面向方面建模中,横切方面没有得到很好的支持。首先,在统一建模语言（UML）元模型的基础上利用类图建立了整体框架模型,设计了核心类、方面、横切元素及其之间的关系;其次,利用UML扩展机制为切点、通知、方面等主要元素建立了新的模型,设计了它们与方面之间新的关联关系并为其定义了语义。通过UML扩展,使得UML能够直接表达面向方面概念,支持面向方面建模设计,实现了面向方面模型的可视化和可辨别性;整体框架模型使得面向方面整体结构清晰,各个核心元素之间关系明确,为面向方面建模提供了一个整体设计平台,提高了面向方面软件设计的模块化,增强了代码的重用性和系统的可维护性。     

面向方面体系结构建模研究

面向方面体系结构建模是面向方面软件开发(AOSD)的重要组成部分,也是近些年面向方面领域研究的热点问题。传统的软件体系结构设计方法没有单独地考虑横切关注点。因此,在软件体系结构设计阶段,建模人员需要新的机制来描述这些横切关注点。本文首先提出一个以横切为中心的面向方面体系结构概念框架;然后通过在体系结构设计阶段引入该框架中的核心概念,提出一种在体系结构设计阶段建模横切关注点的方法,从而支持其在早期进行横切关注点的分离。     

Web-GIS models: accomplishing modularity with aspects

Spatial concerns of Web geographical information systems (Web-GIS) are inherently crosscutting and volatile: crosscutting because they affect multiple functionalities of Web-GIS systems, and volatile because their status may change often. If these concerns are not modularized properly, the quality of Web-GIS services, particularly with regard to adaptation and evolution, can be severely compromised. This paper uses aspect-orientation to model crosscutting and volatile spatial concerns. By modeling both types of concerns, crosscutting and volatile, as candidate aspects, one can use dynamic weaving to add or remove them from a system at runtime. The aspect-oriented approach proposed starts with the identification and specification of crosscutting concerns and follows by composing these using modeling aspects using a transformation approach, an aspect-oriented modeling technique. The conflicts that can emerge due to the composition order are also taken into consideration. Finally, this paper proposes a set of reusable GIS crosscutting concerns, documenting them in a concern catalogue.     

面向方面的UML建模

为了解决软件开发中建模对于系统级关注点被忽略的问题,提出了面向方面的UML建模模型。对面向方面技术和UML进行全面介绍,使其了解它们的主要构成及参数,并基于AspectJ语言扩展UML中的特征文件(profile),来实现面向方面UML建模(AUML)。该扩展是UML体系的一种扩充,它既结合了UML面向对象的特点,又对面向方面横切关注点在语义和结构上进行了规范。最后就图书管理系统进行举例说明,总结了面向方面软件开发(AOSD)profile的参数。     

Assessing the understandability of UML statechart diagrams with composite states—A family of empirical studies

The main goal of this work is to present a family of empirical studies that we have carried out to investigate whether the use of composite states may improve the understandability of UML statechart diagrams derived from class diagrams. Our hypotheses derive from conventional wisdom, which says that hierarchical modeling mechanisms are helpful in mastering the complexity of a software system. In our research, we have carried out three empirical studies, consisting of five experiments in total. The studies differed somewhat as regards the size of the UML statechart models, though their size and the complexity of the models were chosen so that they could be analyzed by the subjects within a limited time period. The studies also differed with respect to the type of subjects (students vs. professionals), the familiarity of the subjects with the domains of the diagrams, and other factors. To integrate the results obtained from each of the five experiments, we performed a meta-analysis study which allowed us to take into account the differences between studies and to obtain the overall effect that the use of composite states has on the understandability of UML statechart diagrams throughout all the experiments. The results obtained are not completely conclusive. They cast doubts on the usefulness of composite states for a better understanding and memorizing of UML statechart diagrams. Composite states seem only to be helpful for acquiring knowledge from the diagrams. At any rate, it should be noted that these results are affected by the previous experience of the subjects on modeling, as well as by the size and complexity of the UML statechart diagrams we used, so care should be taken when generalizing our results.     

A Petri net-based approach for supporting aspect-oriented modeling

The concept of aspect-orientation allows for modularizing crosscutting concerns as aspect modules. Aspect-orientation originally emerged at the programming level, and has stretched over other development phases now. Among them aspect-oriented modeling (AOM) is a hot topic, and there are many approaches supporting it. Petri net is a good formalism which can provide the foundations for modeling software and simulating its execution, but fails to resolve the problem of crosscutting concerns to support AOM. So, this paper presents an approach which extends the Petri net so as to support the AOM. In this paper, the basic functions of the system are modeled as base net by Petri net, and the crosscutting concerns are modeled as aspect nets. In order to analyze the whole system, woven mechanism is proposed to compose the aspect nets and base net together. The problems about aspect-aspect conflict and conflict relations may exist among the aspect nets matching the shared join point, thus this paper propose solutions to resolve them. The Object Petri net which is an extension of traditional Petri net is also extended so as to support aspect-oriented modeling here.     

从UML顺序图生成状态图的一个方法

UML (Unified Modeling Language) is a visual modeling language used for specifying,visualizing,constructing,and documenting the artifacts of software systems by various diagrams.It has been widely accepted as a standard modeling language in both academic and industrial areas.UML sequence diagrams are mostly used in specifying system requirements.By representing interactions,which are arranged in time sequence,between the objects in a system,sequence diagrams can construct scenarios indicating the system‘‘s functions.A UML statechart diagram is a graph shows the sequences of states that an object or an interaction goes through during its life in response to received stimuli,together with its responses and actions.It‘‘s useful in the design stage of system development.This essay discusses the computer-aided transformation from sequence diagrams to statechart diagrams,which can offer strong support for the transfering from requirement analysis to system design in the software development process.With OCL (Object Control Language) semantic constrain,a transform algorithm is provided in the paper.And the differences with the related works are also mentioned.     

A Petri net-based approach for supporting aspect-oriented modeling

The concept of aspect-orientation allows for modularizing crosscutting concerns as aspect modules. Aspect-orientation originally emerged at the programming level, and has stretched over other development phases now. Among them aspect-oriented modeling (AOM) is a hot topic, and there are many approaches supporting it. Petri net is a good formalism which can provide the foundations for modeling software and simulating its execution, but fails to resolve the problem of crosscutting concerns to support AOM. So, this paper presents an approach which extends the Petri net so as to support the AOM. In this paper, the basic functions of the system are modeled as base net by Petri net, and the crosscutting concerns are modeled as aspect nets. In order to analyze the whole system, woven mechanism is proposed to compose the aspect nets and base net together. The problems about aspectaspect conflict and conflict relations may exist among the aspect nets matching the shared join point, thus this paper propose solutions to resolve them. The Object Petri net which is an extension of traditional Petri net is also extended so as to support aspect-oriented modeling here.