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关键词： 数字签名   群签名   标识符   保密通信  

摘要： 最近，Ｔｓｅｎｇ和Ｊａｎ提出了一个基于标识符（ＩＤ）的群签名方案，并称此方案具有诸多优越性。本文从一个新的角度分析了该群签名方案，发现存在三个方面的大漏洞：（１）签名内容泄露签名者的有关秘密参数的信息，签名者身份易被任何人确定：（２）群成员可以单独构造密钥对，从而可以对任意消息Ｍ产生有效签名而不会暴露其身份：（３）群成员可以联合构造有效密钥对，也可以对任意消息Ｍ产生有效签名而不会暴露他们的身份。因此该群签名方案是不安全的。

标准号: LST EN 1571-2001

关键词： Jackson-type operators   DeVore-Gopengauz inequalities  

摘要： In the present paper we consider Jackson-type operators obtained via a Boolean sum, as studied by Cao, Gonska et al. We also present an alternative to their classical method of discretization using appropriate quadrature formulas. Our goal is to obtain for the discretized operators the same degree of approximation as Cao and Gonska (in particular, DeVore-Gopengauz inequalities), at the same time making sure that the operators discretized by means of our method will inherit more properties from the initial operators than by using quadrature formulas. As an example, we will consider convolution-type operators that preserve convexity up to a certain order, and we will show that the operators discretized with our technique also preserve monotonicity and convexity.

关键词： Universal Character Set (UCS)   programming languages   case sensitive   UTF-8   space efficiency   lexicographic sorting order  

摘要： ISO 10646 Universal Character Set (UCS) is a 31-bit coding architecture that covers symbols in most of the world's written languages. Identifiers in programming languages are usually defined by using alphanumeric characters of ASCII, which represent mainly English words. An approach for working around this deficiency is to encode multilingual identifiers into the alphanumeric range of ASCII. For case-sensitive languages, an encoding that utilizes [0-9][A-Z][a-z] can be more space-efficient for multilingual identifiers. This paper proposes a base62 transformation format of ISO 10646 called UTF-62. The resulting string of UTF-62 is within a [0-9][A-Z][a-z] range, a total of 62 base characters. UTF-62 also preserves the lexicographic sorting order of UCS-4. Copyright (C) 2001 John Wiley & Sons, Ltd.

关键词： 菜单   修改注册表   控制面板   项目内容   使用技巧   开始   打印机   文件夹   标识符   计算机  

摘要： 开始菜单上的项目很多,但并不是每个项目我们都需要。同时,我们希望能直接使用的一些项目开始菜单有时也没有直接提供。通过修改注册表等方法,我们可以自己添加或删除开始菜单中的一些项目,从而让开始菜单更简洁实用。

关键词： confidentiality   databases   identification   privacy   research design  

摘要： Objective: This report describes a method for linking separate confidential data sets that contain personal identifying information while preserving required anonymity. Methods: Research data were linked with child abuse and neglect (CAN) report data by an independent "safe" analyst using an identical set of unique identifier codes assigned to each case in both data sets after all personal identifiers had been removed. Results: The research team never learned CAN report status of individuals, the state agency never saw the research data, and the desired analyses were completed using the merged data set. Conclusions: The method was successfully used to merge data from separate sources without divulging confidential information. (C) 2001 Elsevier Science Ltd. All rights reserved.

关键词： 程序设计语言   二进制算术   FORTRAN语言   数据处理   函数   标识符   浮点运算   数值修约   算术运算  

标准号: BS ISO/IEC TR 15580-2001

摘要： This Technical Report specifies an extension of the programming language Fortran, specified by the international standard ISO/IEC 1539-1:1997. Its main aim is to provide support for the five exceptions of the IEEE standard for floating-point arithmetic, but it also provides support for other features of the IEEE standard. A processor is permitted to provide partial support and there are facilities for enquiring about which features are supported or requiring support of certain features. Clause 2 of this Technical Report contains a technical description of the features. It provides an overview and does not include all the fine details. Clause 3 contains the editorial changes to the standard and thereby provides a complete definition.

关键词： Java Card   development environment   formal specification   simulation  

摘要： This article describes a Java Card programming environment which to a large extent is generated from formal specifications of the syntax and semantics of Java Card, the Java Card Runtime Environment (JCRE), and the Java Card APIs. The resulting environment consists of a set of tightly integrated and somewhat smart tools, such as a Java-specific structure editor and a simulator which allows an application to be tested before being downloaded to a card. Furthermore, the simulator analyses the applet in question in order to find out the structure of the accepted commands. This information is then used to automatically adapt the GUI of the simulator. (C) 2001 Elsevier Science B.V. All rights reserved.

关键词： ELECTRONIC journals   INFORMATION retrieval  

摘要： One of the areas of growing interest in professional publishing involves linking articles together. In this session, three issues associated with linking were discussed in detail: linking methodologies, permissions, and appropriate copy. Linking methodologies are based on a unique identifier, which can be algorithmically or non-algorithmically derived. The DOI is a non-algorithmically derived identifier. Permissions are based on knowing who a reader is, what a reader's affiliations are, what subscription rights are tied to those affiliations, and what combination allows access to a particular article. The appropriate copy issue deals with problems arising when a reader has access to multiple versions of the same article. © 2001 by the North American Serials Interest Group, Inc. All rights reserved.

关键词： CAN总线   储粮   水分自动测试系统   通信协议   标识符  

摘要： 介绍基于CAN的储粮水分自动测试系统 。