A straightforward GINO-F line-map editor

A straightforward interactive system for editing a digitized line-map is described here. The map is represented by a pair of forward-pointer linked-lists, the first containing the digitized point-strings, the second an index. Program control commands are supplied via the screen cursor, and allow control of the display, context-based identification of particular digitized points, and basic editing facilities such as point movement, insertion, omission, etc.     

An introductory computer graphics laboratory

Methods are described for teaching students how to write computer programs to perform basic graphics operations. The elementary operations of scaling, translation, reflection, shear, rotation and clipping are presented. Graphics 1000, a Hewlett-Packard graphics software product is the software used. This product imbeds subroutine calls in a FORTRAN program to execute the graphics functions. The laboratory sessions are divided into modules. Module I uses interactive programs to demonstrate graphics operations. Module II introduces Graphics 1000 commands. Module III uses interactive programs to demonstrate XY plotting with as many as four graphs per plot. Module IV uses interactive programs to demonstrate rotation of objects with hidden line removal. Students are assigned tasks ranging from drawing a section of an I beam through rotation of a three-dimensional object. Computer programs used for the demonstrations are available for the students to examine in order to learn how they work.     

Interacting with discrete simulation using on line graphic animation

An interactive system is described which allows for the graphic construction, simulation, and simultaneous animation of an arbitrary network of queues. A method is proposed and implemented for representing the events of a discrete simulation by a continuous animation on a graphics terminal. Techniques are presented for the display of parallel animation ‘sequences’, and a non-trivial mapping of simulation time into animation time is described which preserves the relation order and time relationships between events. The program implemented combines this animation facility with other simulation monitoring and control features. An interactive dialogue which makes use of the lightpen and a menu of commands is implemented for the construction and modification of the queuing network. Certain relevent aspects of man-machine interaction are discussed. The usefulness of this type of approach is discussed with respect to computer-aided design applications, educational tools, and research tools.     

应用手持无线移动终端实现对煤矿井下的断电控制

文章介绍了目前煤矿井下断电控制的现状,阐述了通过手持无线移动终端实现对井下交互断电控制的网络技术架构和断电控制工作原理,给出了手持无线移动终端交互控制系统的主要测试界面实例和主要测试性能,并讨论了需要紧急下达无线断电指令的几种灾害范围。应用手持无线移动终端实现对煤矿井下的断电控制,可突破时空限制,及时动态地掌握煤矿井下灾害异变及灾害涉及的范围,及时下达和执行井下的无线断电控制指令,从而切断井下供电电源,有效防止井下事故发生和灾害的扩大。     

Improving the performance of reverse debugging

Reverse debugging is the software development technique that effectively helps fix bugs occurring at the nondeterministic program behavior. It allows one to examine the past states of the program without rerunning it. An implementation of reverse debugging based on deterministic replay in the QEMU 2.0 emulator is described. A number of techniques improving the debugging performance due to reducing the amount of saved data, optimized storage of system snapshots, indexing, and compressing of the event log are proposed. The emulator can work together with the interactive GDB debugger, which makes it possible to use the reverse-continue, reverse-nexti, reverse-stepi and reverse-finish commands in the course of debugging. The execution time of these commands depends on the frequency of recording the system’s state snapshots. An estimate of the optimal frequency for the reverse-continue command is obtained.     

Multilevel picture segmentation in the graphics system—GRASP

Multilevel graphics structures are highly suited for interactive applications of computer graphics. The facilities concerning the semantics of picture naming and structuring provided by a graphics package are highly influenced by the ease of implementation and operational requirements. This paper presents a multilevel graphics structure provided by GRASP—A 3D Graphics Systems for Pascal users. Picture segmentation commands provided by GRASP allow pictures to be hierarchically structured as collections of sub-pictures which themselves are collections of instances of predifined picture segments. Complex changes in a picture can be effected by commands which allow modifications of graphical entities at specified levels in the picture hierarchy. An edited sub-picture can be redefined as a segment to allow restructuring of the picture hierarchy. The implementation of the scheme presented here has been facilitated through the use of dynamic data structures composed of pointers and records. Powerful error reporting functions aid the programmer considerably in detecting errors if any. A garbage collection scheme conserves working memory space. A couple of applications described at the end of the paper illustrate the flexibility provided by the scheme.     

Displaying Trace Files

Computers generate trace files containing reports on system performance, status and faults. To analyze these trace files more efficiently, we have developed a graphical technique embodied in an interactive system for displaying large trace files. Our system uses abstraction, color, aggregation, filtering, interaction, and a drill-down capability to find patterns among the reports. We apply our system and technique to analyze command accounting trace files from a Unix compute server, showing what commands were executed, by which users, when, and how long the commands ran. We identify resource intensive commands, sequences of commands initiated by a compilations, and commands run with super-user permissions.     

Editing Templates: A User Interface Generation Tool

This article discusses a basic architecture for a user interface management system and the problem of updating a display in response to interactive commands. The basic architecture is then extended to include basic editing and browsing processes on arbitrary data structures. Editing templates are presented as a technique embodying the entire manipulation process for a particular data structure/data display combination. In conjuction with the user interface management system, Such templates are able to automatically provide a majority of the code required in an interactive applicaton.     

开放的VHDL模拟环境OVSE

本文介绍了一个开放的ＶＨＤＬ模拟环境。其基本模块包括：编译器、展开器、连接器和模拟器ＨＳＩＭ，可完成逻辑级的层次设计验证。重点阐述了开放ＶＨＤＬ编译的基本思想，简单叙述了模拟器的前端和后端共享开放模块。这些开放模块研制加环境新的ＶＨＤＬ工具提供了便利的支持。     

A man-machine theorem-proving system

This paper describes a man-machine theorem-proving system at the University of Texas at Austin which has been used to prove a few theorems in general topology. The theorem (or subgoal) being proved is presented on the scope in its natural form so that the user can easily comprehend it and, by a series of interactive commands, can help with the proof when he desires. A feature called DETAIL is employed which allows the human to interact only when needed and only to the extent necessary for the proof.The program is built around a modified form of IMPLY, a natural-deduction-like theorem proving technique which has been described earlier.A few examples of proofs are given.     

Replay-based debugging of occam programs

Parallel programs are intrinsically non-deterministic, and therefore the techniques of cyclical debugging that are commonly used for sequential programs are not suitable for parallel ones. This paper proposes a method to reproduce Occam program behaviour. Saving information on the timer values input by the program and the guards selected at run-time on alternative commands allows program replay, i.e. it makes it possible to re-execute the program deterministically with the same inputs following the same instruction path. This enables the software developer to use tools such as debuggers and intrusive monitors to help identify program faults. After discussing possible implementations of the proposed technique, IRD (an interactive replay debugger for Occam programs) is described. Finally, the use of the IRD in a sample debug session is presented as an example.     

支持笔输入的虚拟家居设计系统

介绍人机交互技术的概况和家居设计软件的开发现状，总结笔交互技术的特点，根据三维场景中的交互任务定义了常用的交互手势集，给出笔交互应用的层次结构，设计了一个虚拟家居设计系统的总体框架，并成功开发了一个基于笔输入的家居设计系统，最后给出了一个设计实例，取得了满意的设计效果。     

单步交互软件中支持用户意图预测的命令设计

针对单步交互的系统,基于MVC(Model View Contoller)和command模式设计系统结构,对交互命令及其参数进行封装;按照最后输入参数优先的原则实现用户选择和捕捉后,根据用户输入的参数预测候选命令集的交互方式;按照任务一致性原则根据用户以前的操作模式预测其当前行为;通过命令信息的保存和恢复,实现Undo,Redo及操作回放等功能.通过该方法实现的交互设计在虚拟施工软件中取得良好的效果.     

Statement inversion and strongest postcondition

A notion of inverse commands is defined for a language which permits both demonic and angelic nondeterminism, as well as miracles and nontermination. Every conjunctive and terminating command is invertible, the inverse being non-miraculous and disjunctive. A simulation relation between commands is described using inverse commands. A generalised form of inverse is defined for arbitrary conjunctive commands. The generalised inverses are shown to be closely related to strongest postconditions.     

Interactive computer programs for fuzzy linear programming with multiple objectives

In this article, we present interactive computer programs fof solving fuzzy linear programming problems with multiple objectives. Through the use of five types of membership functions including non-linear functions, the fuzzy of imprecise goals of the decision maker are quantified. Although the formulated problem becomes a nonlinear programming problem, it can be reduced to a set of linear inequalities if some variable is fixed. Based on this idea, we propose a new method by combined use of bisection method and linear programming method. On the basis of the proposed method, FORTRAN programs that run in conversational mode are developed to implement man-machine interactive procedures. The commands in our programs and major prompt messages are also explained. An illustrative numerical example for the interactive processes is demonstrated together with the computer outputs     

Dispel: A run-time debugging language

Dispel is a language designed to aid communication between an interactive user and a run-time, symbolic debugging system. Important attributes of Dispel are that it provides a small set of primitive debugging actions, most traditional debugging aids (such as variable traces and postmortem dumps) are written in terms of these primitives as debugging routines, and Dispel serves both as an interactive debugging command language and as a special-purpose programming language. The syntax and semantics of Dispel are explained and examples of Dispel commands and routines are presented.     

Talk—an interactive system for a small computer

TALK is an interactive file creation and editing system implemented on a very small computer. It provides facilities for FORTRAN syntax checking and an interactive ‘desk-calculator’. Major computing tasks are sent over a high speed link to CDC 6600/6400 computers A number of teleprinters can be controlled by TALK in the usual way, but also the card reader/line printer pair may be used as a terminal. This is useful for creating or printing large files When a user has logged in he can work in one of several modes. These include INPUT, EDIT and CALCULATE modes. It is possible to nest modes, for example, by entering CALCULATE mode while in INPUT mode without losing one's place in the input file An unusual feature of TALK is the ‘inclusion’ facility. This enables a user to specify previously filed text to be included within another file, either as the file is being created or dynamically whenever the file is used. It also gives users the ability to build up macros of commonly used commands. Many system commands are in fact macros with only simple primitives provided as executable code.     

A general-purpose software measurement tool

A software measurement tool designed for the users of PRIME, an interactive system being developed, is presented. The tool, called SMT, allows its user to instrument a program, modify a pre-existing instrumentation and specify how the collected data are to be reduced by typing in a few simple commands. The user can also write his own measurement routines, which specify the actions to be taken at event detection time, and submit them to the SMT; after checking their correctness, the SMT deals with them as with its built-in, standard measurement routines. The design goals of a general-purpose tool like the SMT are discussed, and the prototype version of the tool, which has been implemented, is described from the two distinct viewpoints of a user and of a measurement-tool designer. An example of the application of the prototype to a measurement problem is illustrated, the reasons why not all of the design goals have been achieved in the implementation of the prototype are reviewed, and some of the foreseeable extensions of the SMT are described.     

Leave and recall: Primitives for procedural programming

Two primitives for structured programming are introduced. The primitives allow a generalized procedure entry and return similar to the ‘loop’ and ‘break’ statements found in many algorithmic languages for control in repetitive commands. Examples are given and the practicality of the primitives especially for interactive programming is stressed. Finally, the detailed implementation of the primitives is discussed; they may be implemented as procedures within an existing language.     

GCI—A tool for developing interactive cad user interfaces

GCI is a Unix-based tool for developing interactive CAD programs. By separating command/ menu definitions from the progam, GCI makes it easier to change and extend the user interface. The language provided by GCI is used to define the syntax of commands, menus, messages, and help text. Generally, GCI supports a static hierarchical structure of commands and menus. However, through a program interface, an application program has the freedom to change environments, commands and menus. This flexibility of run-time control of the user interface is essential for developing highly responsive interfaces in a CAD environment. This paper presents the main concepts and definition language of GCI. It then discusses architectural and implementation issues, and finally presents a typical application's view of using the tool.