模型检测引导的TTCN-3测试套生成技术研究

针对软件测试的不完备性以及软件测试自动化问题,提出在测试过程中将模型检测前置于传统测试,将模型检测与测试相结合。通过分析模型检测中的形式化规约明确测试目的,并转换成TTCN-3(Testing and Test Control Notation)抽象测试套。进一步利用规约中本身存在的正例,与数据类型描述文件相关联,从而生成测试用例。分析TTCN-3开发模式,基于标签转换系统与TTCN-3行为树的等价性,提出模型检测引导的抽象测试套生成算法,并实现TTCN-3抽象测试套的自动生成。     

TTCN-3测试套开发模式及其应用

在测试系统应用研究的基础上,分析TTCN-3测试系统结构,提出适用于软件测试和协议测试的TTCN-3测试套开发模式。该模式借鉴设计模式和模板库思想,在设计和重用抽象测试套和可执行测试套两方面有所突破,可以显著提高测试系统的可复用性和可扩展性,缩短测试系统的开发周期。结合GSM的移动应用部分(MAP)协议栈测试为例,说明该测试套开发模式的实际应用。     

一种TTCN-3编解码器的演化方法

软件需求常常发生变化,导致软件经常被演化。由于 使用TTCN-3对演化后的软件进行测试时需要为大部分测试脚本重新开发编解码器,因此有必要对原来的编解码器进行演化,以提高测试效率。分析了TTCN-3编解码器的研究现状,提出了一种结合测试套文件对编解码器进行演化的方法。实验表明,该方法是可行的,为TTCN-3测试系统的使用提供了方便。     

使用TTPlatForm的防火墙自动测试系统

防火墙自动测试对提高防火墙测试的效率具有很大的意义.在一致性测试框架上,使用TTCN-3测试语言,我们实现TTCN-3测试平台TTPlatForm,提出了一种有效解决防火墙自动测试的方法.它人工干预少,测试结构灵活,测试套开发方便.     

TTCN-3测试系统中模板匹配机制的一种实现方法

TTCN-3拥有一个功能强大且易于掌握的模板匹配机制。本文提出一种TTCN-3测试系统开发过程中模板匹配机制通用的、开放的实现方案。通过对模板匹配功能在TTCN-3测试系统中的作用进行深入分析,采用面向对象的程序设计语言C++实现TTCN-3测试系统中带有匹配机制的模板表示和模板匹配操作,并给出一个对于DNS协议实现功能测试的抽象测试套的翻译方案验证本文设计的合理性。     

基于C++语言转换的TTCN-3测试系统的设计与实现

TTCN-3是一种用于协议与软件测试的标准化测试语言,文章提出了一种实现TTCN-3测试系统的设计方法,将用TTCN-3书编写的抽象测试套先翻译为C 语言,进而编译生成可执行的测试套,然后调度执行.并用这种方法实现了TTCN-3测试平台TTPlatForm,运行结果表明,这种基于语言转换的TTCN-3测试系统在性能、可移植性和灵活性均比采用编译生成成内存对象并调度内存对象执行的方式有了较大的提高.     

TTCN-3 语言非侵入式调试技术

TTCN-3(Testing and Test Control Notation version 3)是一种形式化的测试描述语言,被广泛应用于协议测试等领域。由于测试套的复杂度越来越高,测试人员迫切需要能够调试TTCN-3语言的技术。本文提出了一种非侵入式的TTCN-3语言调试方法,通过驱动第三方调试器对TTCN-3语言编译后生成的目标代码进行调试,同时结合语句映射和符号解析等算法,实现了基本的调试功能。实验结果表明,该调试技术对测试系统的执行性能影响非常小,能更好的满足对大型测试套的调试需求。     

基于TTCN-3的HINOC MAC测试软件TRI和TCI接口设计

研究了HINOC MAC协议测试实现方案和关键接口设计.首先提出了基于TTCN-3的HINOC MAC协议一致性测试平台架构,它包含测试例开发和协议适配器接口开发两部分.重点设计开发TRI(TTCN-3 Runtime Interface)和TCI(TTCN-3Control Interface)接口,以实现信息帧的发送与接收、定时器操作以及编码与解码功能.最后通过搭建实际的测试平台对接口的有效性进行验证,实验结果表明该设计方案可以实现HINOC协议MAC层信令的测试.     

TTCN-3测试系统的设计与实现

TTCN-3是一种新的标准化测试语言,文章提出了基于TTCN-3的协议一致性测试系统的设计方法,它使用可执行对象树表示TTCN-3可执行测试套,提供了灵活的并发测试组件调度方式和解释执行机制,并描述了依据该方法实现的TTCN3Runner的系统结构。     

使用TTCN-3的端到端性能测试系统

介绍了网络端到端性能测试的基本概念和方法。在一致性测试框架上,使用TTCN-3测试语言,设计了端到端性能测试系统TTPerf。它的测试结构灵活,测试套开发方便。     

European Community policy and the market

Abstract This paper starts with some reflections on the policy considerations and priorities which are shaping European Commission (EC) research programmes. Then it attempts to position the current projects which seek to capitalise on information and communications technologies for learning in relation to these priorities and the apparent realities of the marketplace. It concludes that while there are grounds to be optimistic about the contribution EC programmes can make to the efficiency and standard of education and training, they are still too technology driven.     

一种自适应子融合集成多分类器方法

融合集成方法已经广泛应用在模式识别领域,然而一些基分类器实时性能稳定性较差,导致多分类器融合性能差,针对上述问题本文提出了一种新的基于多分类器的子融合集成分类器系统。该方法考虑在度量层融合层次之上通过对各类基多分类器进行动态选择,票数最多的类别作为融合系统中对特征向量识别的类别,构成一种新的自适应子融合集成分类器方法。实验表明,该方法比传统的分类器以及分类融合方法识别准确率明显更高,具有更好的鲁棒性。     

Explanation and prediction: an architecture for default and abductive reasoning

Although there are many arguments that logic is an appropriate tool for artificial intelligence, there has been a perceived problem with the monotonicity of classical logic. This paper elaborates on the idea that reasoning should be viewed as theory formation where logic tells us the consequences of our assumptions. The two activities of predicting what is expected to be true and explaining observations are considered in a simple theory formation framework. Properties of each activity are discussed, along with a number of proposals as to what should be predicted or accepted as reasonable explanations. An architecture is proposed to combine explanation and prediction into one coherent framework. Algorithms used to implement the system as well as examples from a running implementation are given.     

Three Process Perspectives: Organizations, Teams, and People

This paper provides the author's personal views and perspectives on software process improvement. Starting with his first work on technology assessment in IBM over 20 years ago, Watts Humphrey describes the process improvement work he has been directly involved in. This includes the development of the early process assessment methods, the original design of the CMM, and the introduction of the Personal Software Process (PSP)^SM and Team Software Process (TSP){^SM}. In addition to describing the original motivation for this work, the author also reviews many of the problems he and his associates encountered and why they solved them the way they did. He also comments on the outstanding issues and likely directions for future work. Finally, this work has built on the experiences and contributions of many people. Mr. Humphrey only describes work that he was personally involved in and he names many of the key contributors. However, so many people have been involved in this work that a full list of the important participants would be impractical.     

基于复小波噪声方差显著修正的SAR图像去噪

提出了一种基于复小波域统计建模与噪声方差估计显著性修正相结合的合成孔径雷达(Synthetic Aperture Radar,SAR)图像斑点噪声滤波方法。该方法首先通过对数变换将乘性噪声模型转化为加性噪声模型,然后对变换后的图像进行双树复小波变换(Dualtree Complex Wavelet Transform,DCWT),并对复数小波系数的统计分布进行建模。在此先验分布的基础上,通过运用贝叶斯估计方法从含噪系数中恢复原始系数,达到滤除噪声的目的。实验结果表明该方法在去除噪声的同时保留了图像的细节信息,取得了很好的降噪效果。     

How do children do mathematics with LOGO?

Abstract  This paper considers some results of a study designed to investigate the kinds of mathematical activity undertaken by children (aged between 8 and 11) as they learned to program in LOGO. A model of learning modes is proposed, which attempts to describe the ways in which children used and acquired understanding of the programming/mathematical concepts involved. The remainder of the paper is concerned with discussing the validity and limitations of the model, and its implications for further research and curriculum development.     

Editorial: Special issue on recent advances in hybrid control theory and applications

正The demands of a rapidly advancing technology for faster and more accurate controllers have always had a strong influence on the progress of automatic control theory.In recent years control problems have been arising with increasing frequency in widely different areas,which cannot be addressed using conventional control techniques.The principal reason for this is the fact that a highly competitive economy is forcing systems to operate in regimes where     

Information for Authors

正Aim The Journals of Zhejiang University-SCIENCE(A/B/C)areedited by the international board of distinguished Chinese andforeign scientists,and are aimed to present the latest devel-opments and achievements in scientific research in China andoverseas to the world’s scientific circles,especially to stimulateand promote academic exchange between Chinese and for-eign scientists everywhere.     

Enhancing a leaf radiative transfer model to estimate concentrations and in vivo specific absorption coefficients of total carotenoids and chlorophylls a and b from single-needle reflectance and transmittance

The relative concentrations of different pigments within a leaf have significant physiological and spectral consequences. Photosynthesis, light use efficiency, mass and energy exchange, and stress response are dependent on relationships among an ensemble of pigments. This ensemble also determines the visible characteristics of a leaf, which can be measured remotely and used to quantify leaf biochemistry and structure. But current remote sensing approaches are limited in their ability to resolve individual pigments. This paper focuses on the incorporation of three pigments—chlorophyll a, chlorophyll b, and total carotenoids—into the LIBERTY leaf radiative transfer model to better understand relationships between leaf biochemical, biophysical, and spectral properties.Pinus ponderosa and Pinus jeffreyi needles were collected from three sites in the California Sierra Nevada. Hemispheric single-leaf visible reflectance and transmittance and concentrations of chlorophylls a and b and total carotenoids of fresh needles were measured. These data were input to the enhanced LIBERTY model to estimate optical and biochemical properties of pine needles. The enhanced model successfully estimated reflectance (RMSE = 0.0255, BIAS = 0.00477, RMS%E = 16.7%), had variable success estimating transmittance (RMSE = 0.0442, BIAS = 0.0294, RMS%E = 181%), and generated very good estimates of carotenoid concentrations (RMSE = 2.48 µg/cm², BIAS = 0.143 µg/cm², RMS%E = 20.4%), good estimates of chlorophyll a concentrations (RMSE = 10.7 µg/cm², BIAS = − 0.992 µg/cm², RMS%E = 21.1%), and fair estimates of chlorophyll b concentrations (RMSE = 7.49 µg/cm², BIAS = − 2.12 µg/cm², RMS%E = 43.7%). Overall root mean squared errors of reflectance, transmittance, and pigment concentration estimates were lower for the three-pigment model than for the single-pigment model. The algorithm to estimate three in vivo specific absorption coefficients is robust, although estimated values are distorted by inconsistencies in model biophysics. The capacity to invert the model from single-leaf reflectance and transmittance was added to the model so it could be coupled with vegetation canopy models to estimate canopy biochemistry from remotely sensed data.     

Mr. Twinn’s bombes

This article discusses the history and design of the special versions of the bombe key-finding machines used by Britain’s Government Code & Cypher School (GC&CS) during World War II to attack the Enigma traffic of the Abwehr (the German military intelligence service). These special bombes were based on the design of their more numerous counterparts used against the traffic of the German armed services, but differed from them in important ways that highlight the adaptability of the British bombe design, and the power and flexibility of the diagonal board. Also discussed are the changes in the Abwehr indicating system that drove the development of these machines, the ingenious ways in which they were used, and some related developments involving the bombes used by the U.S. Navy’s cryptanalytic unit (OP-20-G).