单链结构实时识别及可视化布局算法研究

数据结构可视化技术是程序理解与调试的一种重要支撑。为解决其中一类应用广泛的数据结构--单链结构的可视化问题，提出一种实时识别与可视化布局算法。首先根据结点入度、主前驱指针和次前驱点集合等结点属性变化对单链结构特征变化的影响，对程序执行过程中的单链结构进行实时识别；然后结合基于图标的静态可视化技术以及动画技术，建立面向单链结构的可视化动作集合及可视化布局方法，形成与程序执行过程步骤实时对应的单链结构可视化表达。最后将该算法应用于新一代集成开发环境AnyviewC的研发与实践中。     

Java可视化编程技巧探究

以学生信息管理系统的开发为背景,采用Eclipse的可视化编程插件Visual Editor作为集成开发环境,Ac-cess 2003作为后台数据库,开发了一款适合初学者使用的SWT单机程序,探讨了Java可视化编程技巧与应用,使初学者由浅入深地学习和掌握Java图形用户界面编程技术。     

面向计算机程序的可视化综述

计算机程序是由开发者使用编程语言编写、被计算机识别并执行的一系列指令.大型程序源代码通常逻辑复杂,句法抽象,造成较大的认知困难.计算机程序可视化以直观形象的方法呈现计算机程序的代码结构、执行过程和运行结果,增强用户理解和调试程序的能力.从程序执行流程出发,根据程序执行的前、中、后3个阶段分析其可视化目标,并介绍已有可视化方法.在程序执行前阶段,使用可视化对代码组织和潜在异常进行多层级、多维度的展示;在程序执行中阶段,利用可视化辅助算法理解、运行调试和状态监测;在程序执行后阶段,运用可视化进行性能评估优化和异常检测.介绍程序可视化在在线编程调试、算法可视化等多种应用场景下的实际应用案例.最后,总结程序可视化现阶段工作的分类以及存在的不足,并指出高泛化性的算法理解可视化和教育领域的运行调试可视化等是未来工作的研究方向.     

基于概念格的信息检索及其树形可视化

概念格作为形式概念分析理论重要的数据表示形式,因其生动简洁地体现概念之间的泛化和特化关系,被广泛应用于知识获取与信息检索领域。在使用概念格进行检索的过程中,随着概念格中概念以及概念之间关系的增加,呈现的格结构容易产生边交叉现象,造成视觉混淆,导致目标信息遗漏。针对这一问题,结合概念格在信息检索方面的优越性以及树形结构在可视化方面的有序性,首先用概念格结构存储数据信息,然后在信息展示时将格结构转化成树形结构,使用户不仅可以通过多条路径检索到目标信息,且结构清晰。最后通过将概念格树形化方法应用于音乐工具分类检索场景中,验证该方法的实用性。     

可视化虚拟机的研究与实现

基于当前科学计算可视化,特别是程序设计可视化的应用和研究,提出一种可视化的虚拟机,并以BASIC语言作为实现的对象.它不仅可以编译执行BASIC程序,其最大的特点是在程序的执行过程中,动态地同步地演示了程序和数据的视图,为理解算法、学习编程和调试程序提供了便利.     

CASL语言可视化运行平台的设计与实现

随着可视化技术的不断发展,越来越多的程序设计语言和集成开发环境采用可视化技术,但是它们基本上只是采用了可视化编程,在软件开发阶段进行可视化,并未采用可视化动态运行程序。为此,进行了程序可视化运行的相关研究,设计出一个实现CASL语言可视化运行的平台。     

X86汇编程序可视调试虚拟机的设计与实现

应用虚拟机构建技术与可视化技术相结合,设计一个汇编程序可视化集成开发环境X86VVM2.实现了一个可执行X86汇编程序的虚拟机内核,在此内核的基础上,进行对程序运行时数据及其执行过程的可视化研究,实现CPU寄存器值及寄存器之间的数据交换可视化、堆栈信息可视化、代码跟踪和调试可视化.同时也实现了一个可视化代码编辑器.经过实验与分析,具备可视调试特征的X86汇编程序集成开发环境可令程序设计者更为直观地理解汇编程序的执行过程,提高调试效率.     

虚拟社群结构特征可视化呈现的社会网络布局算法研究

近年来,随着虚拟社区的发展,社会网络可视化软件逐渐走向普通社区成员的面前。然而现今社会网络可视化领域所采用的布局算法普遍与社会网络分析法相脱离,无法呈现社群结构特征。因此,提出凝聚子群布局算法与核心位置布局算法,它们分别以凝聚子群分析结果和成员整体中心度为布局依据,呈现社群子群和成员位置两种社群结构特征,并且依据实际数据给出布局效果。     

基于代码碎片化的软件保护技术

针对当前软件保护技术存在的不足,提出一种代码碎片化技术,该技术是一种以函数为单元,对函数进行代码shell化、内存布局随机化、执行动态链接化的新型软件保护技术,代码shell化实现代码碎片的位置无关变形,内存布局随机化实现代码碎片的随机内存加载,动态链接化实现对代码碎片的动态执行,通过上述3个环节实现对程序的碎片化处理。实验表明,代码碎片化技术不仅能实现程序执行过程中函数碎片内存位置的随机化,还能实现函数碎片的动态链接执行,增加程序静态逆向分析和动态逆向调试的难度,提高程序的抗逆向分析能力。     

分布式软件动态配置环境可视化的研究与实现

研究了分布式软件开发配置模型OrbGOP的树形配置结构及可视化实现。基于图形编程技术,此模型通过建立构件到结点、构件互操作关系到结点连线的映射,将整个分布式软件的体系结构描述为一张树形逻辑图,用户通过执行图上预定义的一组操作就可以实现系统的动态配置,这使得动态配置工作简单有效,极大地减轻了软件维护的负担。     

Smart Browsing among Multiple Aspects of Data-Flow Visual Program Execution,Using Visual Patterns and Multi-Focus Fisheye Views

This paper presents a scalable visualization technique for automatic animation of data-flow visual program execution, and a software architecture to provide a scalable interface for debugging programs, which exploits a multi-focus fisheye viewing algorithm in conjunction with a semantic zooming interface to show various kinds of information at runtime. The architecture also supports users' browsing with the interface by automatically assigning proper focal points, based on information embedded in the debugged programs. Thus, it is possible to provide scalable views and intelligent assistance for browsing dynamically created data-flow networks. We have incorporated these ideas into the visual tracer of the KLIEG visual parallel programming environment.     

Visual representations for recursion

Visualcode is a visual notation that uses coloured expressions and graphical environments to describe the execution of Scheme programs. RainbowScheme is a program visualization system which is designed to produce visualcode representations of step-by-step execution of Scheme programs. This article presents a new approach of teaching recursion using visualcode and RainbowScheme. Experimental evaluation indicates that viewing RainbowScheme-produced visual traces and requiring students to use visualcode to generate visual evaluation steps of recursive programs can enhance the learners' ability to evaluate recursive programs as well as to solve recursive programming problems.     

数据结构可视化类库的设计与实现

本工作室开发的数据结构可视化类库(JVDSCL,Visual Data Structures Class Library in Java)将可视化技术引入数据结构类库,实现了数据结构可视化。介绍了对数据结构类的可视化扩充方法,给出了实现各种数据结构可视化布局算法的基本框架。JVDSCL可以应用在程序调试和软件开发,提高软件的可视性、重用性与开发效率。     

一种实用的并行程序可视化性能分析方法

并行程序由于自身的复杂性使得并行程序的调试相比串行程序要困难的多，因此用可视化的性能分析工具来辅助并行程序的调试显得非常重要，以此来帮助程序员找到程序的性能瓶颈，为并行程序的优化提供指导和建议。本文在研究MPE性能分析机理的基础上，介绍了一种实用的MPI并行程序可视化性能分析方法，并用实例详细说明了并行程序实时可视化性能分析和事后可视化性能分析过程。     

二叉树的可视化实现

摘要：在计算机科学领域中,二叉树是一种非常重要的非线形结构,实现其可视化具有重要意义。本文运用面向对象方法,利用完全二叉树特点实现了二叉树的可视化,实现了周游二叉树算法的计算可视化,实现了动态可视遍历过程和算法的动态演示同步进行。     

Visualizing massively multithreaded applications with ThreadScope

As highly parallel multicore machines become commonplace, programs must exhibit more concurrency to exploit the available hardware. Many multithreaded programming models already encourage programmers to create hundreds or thousands of short‐lived threads that interact in complex ways. Programmers need to be able to analyze, tune, and troubleshoot these large‐scale multithreaded programs. To address this problem, we present ThreadScope: a tool for tracing, visualizing, and analyzing massively multithreaded programs. ThreadScope extracts the machine‐independent program structure from execution trace data from a variety of tracing tools and displays it as a graph of dependent execution blocks and memory objects, enabling identification of synchronization and structural problems, even if they did not occur in the traced run. It also uses graph‐based analysis to identify potential problems. We demonstrate the use of ThreadScope to view program structure, memory access patterns, and synchronization problems in three programming environments and seven applications. Copyright © 2009 John Wiley & Sons, Ltd.     

PEARD: A Prototype Environment for Active Rule Debugging

This research has investigated dynamic, execution-based rule analysis through the development of a Prototype Environment for Active Rule Debugging, called PEARD. PEARD simulates the execution of active database rules, supporting the Event-Condition-Action rule paradigm. Rule definition is flexible, where changes to rules can be applied immediately during a debugging session without recompiling the system. A breakpoint debugging tool allows breakpoints to be set so that the state of variables may be inspected and changed anytime a breakpoint is reached during rule execution. A rule visualization tool displays the rule triggering process in graph form, supporting different visualization granularities to help the user to understand rule execution. Color coding is also used as part of the visualization tool to help the user see where the different parts of an ECA rule are executed due to deferred coupling modes. Users can examine different parts of the rule graph display to inspect the state of a transaction at different rule execution points. Other debugging features include a means for detecting potential cycles in rule execution and a utility to examine different rule execution paths from the same point in the rule triggering process. Our experience with PEARD has helped to identify some of the useful functional components of an active rule debugging tool and to identify research directions for future active rule development environments.This research was partially supported by NSF Grant No. IRI-9410993.     

PROVIDE: a process visualization and debugging environment

The author introduces PROVIDE, a source-level process visualization and debugging environment currently under development at the University of Illinois at Chicago. PROVIDE is a modern coding and debugging environment that is designed to allow the user to configure interaction at a desired level of abstraction. It emphasizes the use of interactive computer graphics for the illustration of program execution, with special attention to the requirements of program debugging. The major features of PROVIDE are presented, especially the concepts of deferred-binding program animation, which allows users to interactively change the depiction of program execution during the debugging task, and process history consistency maintenance, which guarantees a consistent (automatically updated) record of program execution in the face of changes to program instructions and run-time data values. The current PROVIDE prototype is implemented on Macintosh workstations networked to a VAX 11/780 running 4.2 BSD Unix