逆向工程中动静态结合辅助用例模型的恢复

由于根据目前方法调用之间的“线索”或方法调用的相互关系恢复出的用例模型存在一定的局限性,该文提出了一种基于动态信息并结合静态信息的用例模型恢复方法。该方法以动态运行时的方法调用序列提取基本用例,依据静态的类间关系和静态的程序依赖图对基本用例进行调整、找出用例与角色的交互点及各用例所属的功能模块,使产生的用例模型带有语义信息,更好地辅助用户理解。     

一种基于关注点的用例模型的逆向恢复方法

用例作为展现程序系统级行为的有效手段,可以辅助理解程序的功能特征.针对面向对象系统提出了一种基于关注点的用例模型逆向生成方法.该方法分析目标系统运行时的动态信息,把其中方法调用序列的起始方法看作基本用例,使用一定的规则识别出基本用例间的关系来合并生成用例,依据从用户的关注点中获取到的有用信息,对生成用例进行改进,从而实现了用例模型的逆向生成.通过实验分析,表明该方法在恢复用例模型并提高其准确性方面是有效的.     

一种基于关注点的用例模型的逆向恢复方法

用例作为展现程序系统级行为的有效手段,可以辅助理解程序的功能特征。针对面向对象系统提出了一种基予关注点的用例模型逆向生成方法。该方法分析目标系统运行时的动态信息,把其中方法调用序列的起始方法看作基本用例,使用一定的规则识别出基本用例间的关系来合并生成用例,依据从用户的关注点中获取到的有用信息,对生成用例进行改进,从而实现了用例模型的逆向生成。通过实验分析,表明该方法在恢复用例模型并提高其准确性方面是有效的。     

一种利用动态信息叠加生成用例模型的方法

提出一种利用动态信息叠加生成用例模型的方法。该方法可以利用多次收集到的动态信息,叠加生成目标系统的用例模型并以UML用例图的形式呈现。通过实验测试,使用该方法恢复出来的用例模型接近于实际模型,证明了该方法的有效性。     

基于Sobel的边缘检测方法

使用二种方法进行边缘检测。第一种方法为传统方法;第二种方法为新方法。第一种方法:先用Sobel算子做边缘检测,再用Ostu方法二值化边缘,最后用多像素边缘细化算法进行细化;第二种方法:先用Sobel算子做边缘检测,再用Sobel算子对边缘进行细化,最后用自适应的动态阈值计算方法进行二值化。结果表明:第二种方法在结果和时间上都要优于第一种方法。     

单片机的PWM控制技术

在单片机中实现PWM控制技术的方法及其原理,分析单片机实现PWM功能几种方法的优缺点,分别介绍用单片机的PWM模块实现PWM功能、用程序模拟实现多路PWM功能、用定时器资源实现高分辩率PWM功能和用机外硬件实现PWM功能的方法,并分析这些的方法的优缺点。     

一种改进的用例建模方法及其在电子政务中的应用

用例建模作为一种需求建模方法受到广泛的关注和应用。文章总结了用例建模方法的优点和不足,针对其局限性给出了相应的解决方案,提出了用例建模的改进方法。该方法将传统需求分析思路与用例建模方法有效融合,将分解模式转移至角色模型避免了功能分解,并解决了前置条件降低有效性验证的问题,同时利用可视化建模提高系统模型的易理解性。文章采用改进的用例建模方法对电子文件审批系统进行了需求分析和模型设计,该改进后的用例建模方法可以同时满足用户获取系统价值和引导开发人员系统开发的两方面需求。     

通过静态分析逆向恢复面向对象程序中的用况

在软件维护任务中,通过阅读用况能有效地帮助维护人员理解软件系统,然而在现实中用况文档往往是过时或残缺不全的.如何通过代码分析还原用况是一大难题.针对上述问题提出了一种针对面向对象程序源代码通过静态代码分析逆向恢复用况的方法.该方法在高层通过分析系统逻辑层高层门面类的对象行为协议来获取用况的高层划分,在底层通过分析OO-BRCG(object-oriented branch-reserving call graph)来得到用况的底层划分,然后结合两方面恢复出最终用况.最后通过实验验证了该方法的有效性,恢复用况时该方法能获得极高的用况覆盖度及可观的准确度.     

一种从用例模型到分析模型的设计方法

由于分析模型的复杂性,软件设计师在软件建模过程中往往容易忽略它,直接从用例模型到设计模型,但这样方法难以验证用例的准确性。本文提出了一种从用例模型到分析模型的设计方法,并阐述了这种方法的机理,详细说明了从用例模型中识别分析类的方法,深入探讨了从用例模型中获取实体类的属性及设计分析类的职责。     

基于用例的需求建模方法

传统的软件需求规约是采用功能分解的方式来描述系统功能,而采用用例的方法进行需求获取和建模,是以用户为中心的建模方法.用例模型是由用例图和用例规约所组成的.用例图用来规定系统的行为,用例规约是用文档的形式对每个用例进行描述的.通过对银行系统进行基于用例的需求分析和建模,可以了解用例模型的益处.     

Hierarchy in picture segmentation: a stepwise optimization approach

A segmentation algorithm based on sequential optimization which produces a hierarchical decomposition of the picture is presented. The decomposition is data driven with no restriction on segment shapes. It can be viewed as a tree, where the nodes correspond to picture segments and where links between nodes indicate set inclusions. Picture segmentation is first regarded as a problem of piecewise picture approximation, which consists of finding the partition with the minimum approximation error. Then, picture segmentation is presented as an hypothesis-testing process which merges only segments that belong to the same region. A hierarchical decomposition constraint is used in both cases, which results in the same stepwise optimization algorithm. At each iteration, the two most similar segments are merged by optimizing a stepwise criterion. The algorithm is used to segment a remote-sensing picture, and illustrate the hierarchical structure of the picture     

The Shortest Way to Draw a Connected Picture

With any word over the alphabet  Π={r, , u, ū}  , we associate a connected picture in the following manner: the reading of each letter of this word induces a unit line:  r (, u, ū respectively)  stands for a right (left, up, down respectively) move. We present a rewriting system which can yield, from any word over Π, all the words describing the same picture. Particularly, we give an algorithm to find a minimal word describing a given picture: this word represents the shortest way to draw this picture without 'penup'.     

A method of rotating areas on a raster scan graphic display

The method presented here permits an area of a picture held in a frame store to be rotated in the plane without recourse to a data structure or other picture definition. It is therefore suitable for use with digitized images and hand-drawn ones. Four techniques based on interpolation are compared and some performance figures are given. In addition, the effect of the computation on the appearance of the picture is discussed, a specific example being included.     

Type classification of fingerprints: a syntactic approach

A fingerprint classification procedure using a computer is described. It classifies the prints into one of ten defined types. The procedure is implemented using PICAP (picture array processor). The picture processing system includes a TV camera input and a special picture processor. The first part of the procedure is a transformation of the original print to a sampling matrix, where the dominant direction of the ridges for each subpicture is indicated. After smoothing, the lines in this pattern are traced out and converted to strings of symbols. Finally, a syntactic approach is adopted to make the type classification based on this string of symbols.     

Linear time algorithm for finding a picture''s connected components

An algorithm that identifies the connnected components of a thresholded digitized picture is presented. The time complexity of the algorithm is linear in the number of runs of object pixels in the picture.     

计算机监控画面的快速生成方法

本文介绍一种在自动化过程控制中应用的快速生成计算机监控画面的经验方法。     

An approach to a calculation-minimized hidden line algorithm

Hidden line algorithms based only on picture primitives, cannot recognize the areas of a picture which are completely visible or invisible. By testing each primitive of these areas they produce an overhead of calculation. Moreover, they waste time by first calculating the hidden lines explicitely and then displaying the remaining edges. This paper describes a method, which rather computes the visible parts of a picture, than excludes the invisible ones. Furthermore an approach to recognize complete visible areas instead of single visible edges is made. A comparison with other techniques will show the qualitatively better calculation rate of the new method.     

Tour Into the Picture using a Vanishing Line and its Extension to Panoramic Images

Tour into the picture (TIP) proposed by Horry et al. ¹³ is a method for generating a sequence of walk-through images from a single reference picture (or image). By navigating a 3D scene model constructed from the picture, TIP produces convincing 3D effects. Assuming that the picture has one vanishing point, they proposed the scene modeling scheme called spidery mesh. However, this scheme has to go through major modification when the picture contains multiple vanishing points or does not have any well-defined vanishing point. Moreover, the spidery mesh is hard to generalize for other types of images such as panoramic images. In this paper, we propose a new scheme for TIP which is based on a single vanishing line instead of a vanishing point. Based on projective geometry, our scheme is simple and yet general enough to address the problems faced with the previous method. We also show that our scheme can be naturally extended to a panoramic image.     

Vocabulary development at home: a multimedia elaborated picture supporting parent–toddler interaction

Some children enter elementary school with large vocabulary delays, which negatively influence their later school performance. A rich home language environment can support vocabulary development through frequent high‐quality parent–toddler interaction. Elaborated picture home activities can support this rich home language environment. This study compares the effects of a multimedia versus a paper elaborated picture on the parent–toddler interaction and toddlers' vocabulary development. In a within‐subjects design, 20 toddlers (age 3–4) discussed a multimedia and a paper elaborated picture with a parent. Results showed that toddlers knew significantly more words (receptively and expressively) after both activities. Moreover, the improvement in receptive vocabulary knowledge was significantly larger with the multimedia elaborated picture compared with the paper‐based picture. In addition, both parent and toddler engaged in a significant higher level of decontextualized language in response to multimedia. The present study shows that multimedia elaborated pictures can support parents at home to engage in a parent–toddler interaction that is richer and supports the development of receptive vocabulary more compared with traditional paper‐based activities. In the future, multimedia‐based home activities for toddlers' vocabulary development, supporting parent–child interaction, can be offered relatively cheap and easily via internet.     

From chaos and cosmology: a new space for the visual arts

By sourcing ideas in contemporary cosmology, chaos theory and mathematics, and using these to formulate an approach to visual representation, the potential for new visual expressions arises. This paper introduces a curved picture space, which offers a rationale for projections of imagery in painting and computer art, based on shapes. Curved picture space is based on a spiral, and the encyclopedia of shapes provides alternative possibilities.