Mutual recognition of the results of measurements and tests and formation of a world-wide metrology system

The main prerequisites are considered in a historical aspect and steps ate taken in creating a world-wide metrology system with the aim of providing conditions for the mutual recognition of measurement results. __________ Translated from Izmeritel’naya Tekhnika, No. 11. pp. 59–62, November, 2007.     

Investigating dependencies in software requirements for change propagation analysis

ContextThe dependencies between individual requirements have an important influence on software engineering activities e.g., project planning, architecture design, and change impact analysis. Although dozens of requirement dependency types were suggested in the literature from different points of interest, there still lacks an evaluation of the applicability of these dependency types in requirements engineering.ObjectiveUnderstanding the effect of these requirement dependencies to software engineering activities is useful but not trivial. In this study, we aimed to first investigate whether the existing dependency types are useful in practise, in particular for change propagation analysis, and then suggest improvements for dependency classification and definition.MethodWe conducted a case study that evaluated the usefulness and applicability of two well-known generic dependency models covering 25 dependency types. The case study was conducted in a real-world industry project with three participants who offered different perspectives.ResultsOur initial evaluation found that there exist a number of overlapping and/or ambiguous dependency types among the current models; five dependency types are particularly useful in change propagation analysis; and practitioners with different backgrounds possess various viewpoints on change propagation. To improve the state-of-the-art, a new dependency model is proposed to tackle the problems identified from the case study and the related literature. The new model classifies dependencies into intrinsic and additional dependencies on the top level, and suggests nine dependency types with precise definitions as its initial set.ConclusionsOur case study provides insights into requirement dependencies and their effects on change propagation analysis for both research and practise. The resulting new dependency model needs further evaluation and improvement.     

基于开发者协作关系和信息检索的需求跟踪系统

目前自动化需求跟踪的研究广泛使用文本信息检索技术。然而信息检索会遗漏一些文本不相似但是实际相关的软件制品,导致自动化跟踪的精度不高。针对上述问题,提出利用开发者协作关系来进行优化,研发了基于开发者协作关系和信息检索的需求跟踪系统。该系统在进行需求跟踪时,首先用信息检索推荐与需求文本上相似的代码,然后从代码提交日志中挖掘开发者协作关系,根据开发者协作关系再推荐相关代码,用户根据两次推荐的结果确定正确的需求代码跟踪关系。试验结果表明该系统能够找到信息检索遗漏的需求跟踪关系,能够提高自动化跟踪的准确性,节省跟踪时间。     

基于渔船监测系统的近海捕捞水产品溯源

通过对渔船监测系统的船位、航向、航速等信息挖掘,可以进行水产品溯源,保障海洋水产品的食品安全。基于渔船监测系统数据,结合渔场、沿海区划等信息,构建近海捕捞水产品溯源模型,研究渔船溯源、渔区和渔场溯源、渔获溯源,为水产品安全保障提供参考依据。     

基于场景元模型的软件产品线追踪方法

针对软件产品线需求追踪方法进行了研究,基于软件产品线领域需求分析、设计、实现三个阶段的信息传播,提出了一种基于场景元模型的多层次软件产品线追踪模型,完整描述了追踪信息变化的整体框架;建立了需求—用例追踪矩阵、用例—动作追踪矩阵、动作—构件追踪矩阵;根据矩阵运算,描述了具体追踪实现过程,通过一个ATM案例验证了该方法对于软件产品线领域需求获取以及需求变更等问题的解决有较好的效果。     

一种门限可追踪的匿名签密方案

为解决匿名签密算法中签密者身份的追踪问题,提出了一种门限可追踪的匿名签密方案.该方案借助范德蒙行列式生成成员的公钥和私钥,通过在匿名签密过程中附加一些与签密者身份相关的额外信息,实现签密者身份的门限追踪.在不可分模型下,证明了该方案满足匿名性、门限可追踪性、不可伪造性和不相关性.     

基于卫星共视法的电网时频测量及同步技术

时间同步对电网的安全和管理有着重要影响,如何准确可靠地同步电网时间值得研究。为此,提出利用卫星共视技术进行电网时间频率的远程校准、进而实现电网时间同步的方法。首先,提出电力系统的四级时间频率溯源体系,明确了电网时间频率溯源关系。其次,研究建立了可以满足卫星共视要求的时间频率计量标准装置,依托标准装置,将卫星共视技术应用于电力系统时间频率远程校准中,利用卡尔曼滤波算法去除干扰,并分析了基于卫星共视技术的电网时间频率同步方法。为定量评价提出方法的有效性,研究了采用提出的方法进行溯源时的时间不确定度和频率不确定度。实验及分析结果表明,提出的方法可以实现时间频率量值的高精度远程传递,从而保障电力系统中的时间同步。     

Advanced product planning: a comprehensive process for systemic definition of new product requirements

This paper reports results of research into the definition of requirements for new consumer products––specifically, electro-mechanical products. The research dealt with the derivation of design requirements that are demonstrably aligned with stakeholder needs. The paper describes a comprehensive process that can enable product development teams to deal with statements of product requirements, as originally collected through market research activities, in a systematic and traceable manner from the early, fuzzy front end, stages of the design process. The process described has been based on principles of systems engineering. A case study from its application and evaluation drawn from the power sector is described in this paper. The case study demonstrates how the process can significantly improve product quality planning practices through revision of captured product requirements, analysis of stakeholder requirements and derivation of design requirements. The paper discusses benefits and issues from the use of the process by product development teams, and identifies areas for further research. Finally, the conclusions drawn from the reported research are presented.

具有向后无关性的本地验证撤销群签名方案

用户撤销是群签名中的一个重要问题,本地验证撤销(VLR)是一种有效的解决方法.2004年CCS的Boneh-Shacham方案是签名长度很短的VLR方案,但它不具有向后无关性(BU).此后BU-VLR群签名方案被提出来,效率却弱于Boneh-Shacham方案.基于弱DTDH假设和q-SDH假设,首先提出一种BU-VLR群签名方案,具有较短的签名长度和较低的运算量.其次为了减少公布在撤销列表上的数据,给出扩展方案.最后用构造签名的方法,改进2007年IEICE中Nakanishi-Funabiki方案,使得到的签名长度更短,运算量保持不变.     

基于可再分发抗合谋编码的低失真水印方案

在大数据的时代背景下,数据潜在的价值使其成为重要的财富之一。数据的非法篡改、修正和非法分发给追踪数据的泄密源头带来巨大挑战。数字指纹技术可应用在数据泄密溯源领域,即在数据中嵌入一串能够唯一标识用户信息的序列,当数据发生泄密后,提取其中蕴含的数字指纹,追踪到泄密的叛逆者。多个用户对数据合谋攻击并泄密数据,从而毁坏其中嵌入的指纹信息达到逃脱追责的目的,抗合谋编码能够解决此问题。针对现有的数字指纹编码无法满足数据再分发需求、数字指纹嵌入造成较大数据失真的问题,本文使用BIBD（Balanced incomplete block design）作为外码,码字扩展后的C码作为内码,构建一种可再分发的抗合谋指纹编码RD-ACC（Redistributable anti-collusion fingerprint coding）。在此基础上,提出一种基于多目标优化的数据库指纹算法,能够在较小的数据库失真情况下保证数字指纹较高的鲁棒性,提取出的RD-ACC能够有效抵抗组内、组间多用户合谋攻击。实验结果表明,该算法能够在较小的数据失真下实现数据的再分发操作,并且能抵抗合谋攻击进行泄密溯源。