CRYPTANALYSTS' CORNER

Abstract

The Hill cipher, also known as matrix encryption, is a polygraphic substitution cipher, developed by the mathematician Lester S. Hill in 1929. While various attacks had been known on the Hill cipher, the ciphertext-only attack without assumptions about the encryption matrix or probable plaintext words was introduced only recently by Bauer and Millward. They obtained high efficiency of attack by recovering the decryption matrix row by row rather than all rows at once. In this paper, we extend their ciphertext-only attack in two ways. First, we present a better scoring system for cryptanalysis based on the goodness-of-fit statistics. Specifically, we reduce the average number of candidate rows from 24.83 to 7.00 for 3 × 3 matrix and from 4027.78 to 1220.38 for 4 × 4 matrix. Second, we show how to apply our attacks to the Hill cipher without knowing the numeric equivalents of the letters of the plaintexts.     

Studying L2 writers’ digital writing: An argument for post-critical methods

Because the fields of digital writing and second language (L2) writing both have rich methodological traditions, researchers designing a study that examines issues at the intersection of these two fields have multiple methodological traditions to draw upon. Recognizing the choices that researchers face, we advocate adopting post-critical methodologies, as articulated by Patricia Sullivan and James E. Porter for these digital/L2 inquiries. A post-critical approach, we believe, enhances these studies by emphasizing their interdisciplinary and ideological nature. After defining what a post-critical methodology entails, we connect it to recent research trends in digital writing, L2 writing, and L2 studies. To help future researchers design digital/L2 writing studies, we explain the implications of these approaches.     

Intelligent computer-assisted language learning: A bibliography

This bibliography focuses on works discussing intelligent computer-assisted language learning (ICALL). It includes over 200 entries divided into three sections: (1) collections, special issues and bibliographies, (2) general/theoretical works, (3) specific applications.Alan Bailin (Ph.D., McGill) is Associate Editor ofComputers and the Humanities. He has participated in the field of Intelligent Computer-Assisted Language Learning as a writer, editor, and researcher. He has also published in the areas of linguistics and semiotics.     

壮文与壮文信息处理

壮族的文字分为古壮文和现代壮文。古壮文主要出现在古籍中,民间也仍在使用,是活体字。1990年起广西研制了古壮文造字/编辑/排版工具、释义字典和借音壮字数据库。现代壮文创制于1955年,是壮族扫盲/教学、国家党政重要文件、人民币、广西公共场所使用的文字。目前已有编辑工具、英汉壮释义词典及辅助翻译软件。今后应研究壮文标准,研究开发全文检索和古壮—现代壮—汉—英互译系统,以推动壮文教育、出版、交流与遗产保护。     

Computers and writing: Casting a broader net with theory and research

Today, teachers of English are faced with the problem of developing new vantage points from which to consider the use of computers in writing programs, writing classrooms, and individual writing processes. Until this time, the profession has subscribed to a limited view of computers and their effects on writing — a view circumscribed by the paradigms of other disciplines or by our own past experiences with teaching machines and paper-and-pencil composing. These visions are not capable of accommodating the larger and more radical changes wrought by the electronic medium we are now using. By subscribing to them, English teachers may, as Coleridge says, have created a tacit compact not to pass beyond a certain limit in speculating about computers. This paper suggests four overlapping areas of exploration, four points of departure that might help us spark creative re-formations of our thinking about computers and their relationship to writing: 1.) Computers and teaching writing, 2.) Computers and language theory, 3.) Computers and learning from the past, 4.) Computer research in other fields.Cynthia Selfe has been chair of the NCTE assembly of Computers in English and a member of the CCCC Committee on Instructional Technology. Billie J. Wahlstrom is chair of the Graduate Program in Rhetoric and Technical Communication at Michigan Technological University and a consultant on interactive videodisc design for Michigan Tech Software.     

Intelligent computer assisted blog writing system

In this paper, we designed and implemented an intelligent computer assisted blog writing system. The system includes concept expansion module, text generation module and content replacement module. The concept expansion is employed to expand the concept provided by the user and these expanded concepts can provide the system more semantic information. The text generation model is based on keyword generation model and text segment generation model of which the important keywords are extracted from system corpus to serve as the backbone of the template. Meanwhile, the text segments between keywords will make up the content of the template and candidate text segments are retrieved from the corpus based on statistical analysis. The content replacement module employs Google to retrieve content from the Web and ranks the content based on term and POS tagging similarities. The prototype system has shown that it could work well on blog writing application domain and the concept of this research could be extended to other domains easily.     

Interactive Management of Human Factors Knowledge for Human Systems Integration Using Systems Modeling Language

Abstract

The field of Human Factors in Knowledge Management is often seen as a problem of capturing, organizing, and retrieving information to build knowledge. This process is inextricably bound up with human cognition and, as such, the management of knowledge occurs within an intricately structured behavioral, cultural, and social context. This paper emphasizes the importance of interactive human factors in knowledge management and introduces a model-based human systems integration framework based on systems modeling language (SysML).     

Parallel developments in programming languages and operating systems

Three stages of the development of programming languages are examined and compared with similar stages in the development of operating systems. It is noted that not only do these stages agree but particular developments within these stages also have remarkable similarities; some of these are superficial while others are deeper. The parallels are used to note that certain developments have yet to occur in operating systems. Finally, the essential identity of purpose of programming languages and operating systems is discussed.     

An environment for prototyping distributed applications

Designing a distributed application is an extremely complex task. Proper facilities for prototyping distributed applications can be useful in evaluating a design, and also in understanding the effect of different parameters on the performance of an application. We describe a language for prototyping distributed applications, that supports different communication primitives with specified delay, and provides primitives to aid debugging and evaluation. Our environment for executing distributed programs supports heterogeneous computation in which processes can execute on different hardware. Different source languages can be used for coding different modules of the processes. The system has a centralized control and monitoring facility which is based on the Suntools window system.     

中国手语信息处理述评

为了能够有效地对中国手语进行信息处理,需要针对中国手语的特性提出相应的信息处理方案。该文根据国内外的研究进展情况,从基于规则和基于语料库的角度,讨论了中国手语信息处理过程中遇到的有关问题,并提出可借鉴的中国手语信息处理技术,同时从中国手语自身的词法、句法出发,参考国外手语语言学的最新研究成果,讨论了中国手语信息处理中有关信息表征、理解、生成等问题。最后指出未来手语的信息处理将会更多地建立在跨学科、多模式的基础之上 ,该项研究将有力地促进信息无障碍技术的发展。
     

基于曲率的尺度空间中的角点增强

角点检测在模式识别、计算机视觉和其它相关领域中占有重要地位．由于无法事先确定应在什么尺度下进行检测，我们很难从平面曲线中准确地提取出角点．本文阐述了通过曲线尺度空间（Curvescalespace）来增强角点的方法．该方法的主要思想是通过曲线的形变（或构造曲线尺度空间）使曲线上的角点随着尺度的增加变得更加突出，以便准确地提取出角点．从广义的几何热扩散方程（GGHF）出发，我们得到了该方法中曲线曲率的演化形式，它揭示了构造基于曲率的尺度空间与形成尺度空间所需符合的准则二者间的本质联系．本文研究GGHF符合尺度空间准则的条件并给出了寻找不同的符合尺度空间准则的曲线演化方法，与此同时，我们给出了角点可被增强的条件．在符合上述条件的前提下，本文给出了一种新的构造尺度空间的方法，该方法符合尺度空间的准则，并能够在去除噪声和不重要的小结构的同时，有效地增强曲线上的重要角点．     

游戏脚本语言的研究

分析并总结了脚本语言的优势与缺点,分析了脚本语言在游戏开发中的应用,介绍了Python、Lua、等语言特点,总结了Python、Lua等语言在游戏开发方面的应用,指出了脚本语言在未来游戏开发中的趋势。     

基于深层语言模型的古汉语知识表示及自动断句研究

古文句读不仅需要考虑当前文本的语义和语境信息,还需要综合历史文化常识,对专家知识有较高要求.该文提出了一种基于深层语言模型(BERT)的古汉语知识表示方法,并在此基础上通过条件随机场和卷积神经网络实现了高精度的自动断句模型.在诗、词和古文三种文体上,模型断句F1值分别达到99％、95％和92％以上.在表达较为灵活的词和...     

基于知识的快速角点提取

本文提出一种基于查表技术知识的基角点提取方法．就一定的考察点数目来说，该方法由于采用了人的知识，其检测效果是很好的．由于采用了查表技术，该方法的速度非常快，并且易于硬件实现．当用硬件实现该方法，对于５１２×５１２的真实图像，角．点提取能以电视速率进行．本文详细讨论了查找表的构造方法和知识的采集方法．实验表明该方法工作得很好．     

ESL students’ experiences of online peer feedback

With the popularity of computer technology, online peer feedback has become common in university writing classes. This paper reports an exploratory study of 22 English as a Second Language (ESL) students’ experiences of online peer feedback in a sheltered credit course at a western-Canadian university. Based on analyses of the electronic feedback (e-feedback) participants received, comparisons of their initial and revised drafts, and follow-up interviews, the study shows that e-feedback, while eliminating the logistical problems of carrying papers around, retains some of the best features of traditional written feedback, including a text-only environment that pushes students to write balanced comments with an awareness of the audience's needs and with an anonymity that allows peers to make critical comments on each others’ writings. However, the participating ESL students expressed little confidence in peer commenting in general. Some shied away from the demand to express and clarify meaning, which turned online peer feedback into a one-way communication process, leaving a high percentage of peer comments not addressed. An intervention of face-to-face class discussion with teacher's guidance to clarify comments in question is suggested to maximize the effect of online peer feedback.     

基于支持向量机的角点检测方法研究

支持向量机是一种基于VC维理论和结构风险最小化原则的统计学习方法,具有小样本学习、推广能力强、解为全局最优等优点.基于支持向量机的角点检测方法,不需要梯度信息,只需对角点样本进行学习,找出角点的特征信息,便可实现对角点的正确检测.通过恰当选取核函数、参数值以及训练样本集,实现了对摄像机标定模板角点的正确检测,并且对畸变角点和含噪声角点也有很好的检测效果.与传统方法相比,所提出的方法具有更强的角点检测能力.     

基于URL的JAVA语言网络通讯系统的设计与实现

JAVA是一种应用比较广泛的网络编程语言,它具有简单、面向对象、安全等特点。文中对JAVA语言的URL网络通讯机制进行介绍,根据URL理论及方法创建一条和所选资源链接的通讯通道,提出JAVA语言通信网络资费系统的设计。     

PML: Toward a High-Level Formal Language for Biological Systems

Documentation of knowledge about biological pathways is often informal and vague, making it difficult to efficiently synthesize the work of others into a holistic understanding of a system. Several researchers have proposed solving this problem by modeling pathways using formal languages, which have a precise and consistent semantics. While precise, many of these languages may be too low-level to model feasibly complex pathways. We have developed the Pathway Modeling Language (PML), a high-level language for modeling pathways. PML is based on a biological metaphor of molecules with binding sites and has special constructs for handling compartment changes in pathways. Our preliminary work has shown that PML's language constructs serve as a promising basis for modeling complex pathways in a readable and composable manner.