多重代理多重盲签名方案

多重代理多重盲签名方案综合了多重代理多重签名方案和盲签名方案的优点,它是由一组原始签名人授权给一组代理签名人,并且这组代理签名人并不知道消息的具体内容。基于离散对数问题提出广播多重代理多重盲签名方案和有序多重代理多重盲签名方案,通过对其安全性分析,两类方案均满足多重代理多重签名的安全性及盲签名的盲性和不可链接性。     

一种基于椭圆曲线的多重代理多重数字签名方案

随着对数字签名的研究和应用的不断深入,人们相继提出了多重签名、代理签名,后来又提出了多重代理签名、代理多重签名等.作者在这里提出了一种基于椭圆曲线密码体制的多重代理多重数字签名方案.在这种方案中,一组原始签名人可以共同授权给一组代理签名人,在所有原始签名人和代理签名人的同意下,代理签名组所有成员可以一起代替原始签名组行使签名权利.     

一个新的基于离散对数问题的多重代理多重签名方案

详细分析几个基于离散对数问题的多重代理多重签名方案,这些方案存在的缺陷和不足都已指出,并给出攻击方法。基于代理签名和多重签名,通过签名算法的改进,给出一种新的多重代理多重签名方案,并着重分析方案的正确性和安全性。在该方案中,可以避免滥用代理签名权,抵抗公钥替换攻击,满足不可伪造性,不可否认性,不可追踪性等特性。新方案在安全性方面有着较强的优势。     

一种新的签名--有代理的多重签名研究

该文在研究多重签名和代理签名的基础上,提出了一种新的签名——有代理签名的多重签名,在这种多重签名中,允许部分签名人委托其代理人进行签名。普通的多重签名和代理多重签名是这种签名的特殊形式。讨论这种签名的安全性有助于多重签名和代理多重签名的安全性研究。之后,该文提出了二种有代理的多重签名方案,并对方案的安全性进行了分析。     

基于ECC的多重代理多重签名方案

多重代理多重签名体制中，原始签名群可以将签名权利委托给代理签名群，再由这些代理签名人联合生成一个代表所有原始签名人的数字签名。通过对ECC签名方案和多重代理多重签名的分析，提出了一个基于ECC的多重代理多重签名方案，该方案有较好的安全性和实用性。     

基于ECC的多重代理多重签名方案

多重代理多重签名体制中,原始签名群可以将签名权利委托给代理签名群,再由这些代理签名人联合生成一个代表所有原始签名人的数字签名。通过对ECC签名方案和多重代理多重签名的分析,提出了一个基于ECC的多重代理多重签名方案,该方案有较好的安全性和实用性。     

基于ECC的多重代理多重盲签名方案

在讨论代理多重签名方案、多重代理签名方案、多重代理多重签名方案及盲签名方案设计原理的基础上,将多重代理多重签名方案与盲签名方案相结合,提出基于椭圆曲线密码的广播多重代理多重盲签名方案和有序多重代理多重盲签名方案,并对其进行安全性分析,分析结果表明,2类方案均满足多重代理多重签名的安全特性及盲签名的盲性和不可追踪性。     

无证书多重代理多重盲签名方案

为了提高盲签名的安全性和实用性,结合无证书公钥密码体制、多重代理多重签名和盲签名,首次提出了一个无证书多重代理多重盲签名方案。在该方案中,需要所有的原始签名者合作才能完成代理授权,同时只有所有的代理签名者合作才能产生多重代理多重盲签名。该方案解决了多个代理签名者代表多个原始签名者进行盲签名的问题。经分析得知,方案同时具有多重代理多重签名和盲签名所需的安全特性。     

一种基于椭圆曲线的多重代理多重签名方案*

在研究代理多重签名和椭圆曲线数字签名的基础上,提出了一种基于椭圆曲线的多重代理多重签名方案。一组原签名人可以共同授权给一组代理签名人,授权代理签名组的所有成员一起可以代替原签名组成员行使签名权利。其安全性基于求解椭圆曲线离散对数的困难性,比已有的方案更加安全、高效;最后讨论了其正确性和有效性。     

基于椭圆曲线的有代理的多重签名

在研究有代理的多重签名和椭圆曲线数字签名的基础上,提出了一种基于椭圆曲线的有代理的多重签名方案。其安全性基于求椭圆曲线离散对数的困难,比起已有的方案更加安全、高效,并给出了两种基于椭圆曲线的有代理的多重签名方案,即广播的有代理的多重签名方案和有序的有代理的多重签名方案;最后讨论了其正确性和安全性。     

Only connect: teaching, technology and telesis

Abstract This paper describes an approach to the design of interactive multimedia materials being developed in a European Community project. The developmental process is seen as a dialogue between technologists and teachers. This dialogue is often problematic because of the differences in training, experience and culture between them. Conditions needed for fruitful dialogue are described and the generic model for learning design used in the project is explained.     

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。     

煤矿井下安全监控分站的设计及其仿真实现

为了设计一种具有低成本、低功耗、易操作、功能强且可靠性高的煤矿井下安全分站,针对煤矿安全生产实际,文章提出了采用MCS-51系列单片机为核心、具有CAN总线通信接口的煤矿井下安全监控分站的设计方案;首先给出煤矿井下安全监控分站的整体构架设计,然后着重阐述模拟量输入信号处理系统的设计过程,最后说明单片机最小系统及其键盘、显示、报警、通信等各个组成部分的设计;为验证设计方案的可行性与有效性,使用Proteus软件对设计内容进行仿真验证,设计的煤矿井下安全监控分站具有瓦斯、温度等模拟量参数超标报警功能和电机开停、风门开闭等开关量指示功能;仿真结果表明:设计的煤矿井下安全监控分站具有一定的实际应用价值.     

Avoiding semantic and temporal gaps in developing software intensive systems

Development of software intensive systems (systems) in practice involves a series of self-contained phases for the lifecycle of a system. Semantic and temporal gaps, which occur among phases and among developer disciplines within and across phases, hinder the ongoing development of a system because of the interdependencies among phases and among disciplines. Such gaps are magnified among systems that are developed at different times by different development teams, which may limit reuse of artifacts of systems development and interoperability among the systems. This article discusses such gaps and a systems development process for avoiding them.     

Designing economic np control charts: A programmed simulation approach

This paper presents control charts models and the necessary simulation software for the location of economic values of the control parameters. The simulation program is written in FORTRAN, requires only 10K of main storage, and can run on most mini and micro computers. Two models are presented - one describes the process when it is operating at full capacity and the other when the process is operating under capacity. The models allow the product quality to deteriorate to a further level before an existing out-of-control state is detected, and they can also be used in situations where no prior knowledge exists of the out-of-control causes and the resulting proportion defectives.     

The development of robot art

Going through a few examples of robot artists who are recognized worldwide, we try to analyze the deepest meaning of what is called “robot art” and the related art field definition. We also try to highlight its well-marked borders, such as kinetic sculptures, kinetic art, cyber art, and cyberpunk. A brief excursion into the importance of the context, the message, and its semiotics is also provided, case by case, together with a few hints on the history of this discipline in the light of an artistic perspective. Therefore, the aim of this article is to try to summarize the main characteristics that might classify robot art as a unique and innovative discipline, and to track down some of the principles by which a robotic artifact can or cannot be considered an art piece in terms of social, cultural, and strictly artistic interest. This work was presented in part at the 13th International Symposium on Artificial Life and Robotics, Oita, Japan, January 31–February 2, 2008     

View-based model-driven architecture for enhancing maintainability of data access services

In modern service-oriented architectures, database access is done by a special type of services, the so-called data access services (DAS). Though, particularly in data-intensive applications, using and developing DAS are very common today, the link between the DAS and their implementation, e.g. a layer of data access objects (DAOs) encapsulating the database queries, still is not sufficiently elaborated, yet. As a result, as the number of DAS grows, finding the desired DAS for reuse and/or associated documentation can become an impossible task. In this paper we focus on bridging this gap between the DAS and their implementation by presenting a view-based, model-driven data access architecture (VMDA) managing models of the DAS, DAOs and database queries in a queryable manner. Our models support tailored views of different stakeholders and are scalable with all types of DAS implementations. In this paper we show that our view-based and model driven architecture approach can enhance software development productivity and maintainability by improving DAS documentation. Moreover, our VMDA opens a wide range of applications such as evaluating DAS usage for DAS performance optimization. Furthermore, we provide tool support and illustrate the applicability of our VMDA in a large-scale case study. Finally, we quantitatively prove that our approach performs with acceptable response times.     

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.     

A pragmatic multi-method investigation of discrepant technological events: Coping,attributions, and ‘accidental’ learning

Discrepant technological events or situations that entail a problem, a misunderstanding or a difficulty with the Information Technology (IT) being employed, are common in the workplace, and can lead to frustration and avoidance behaviors. Little is known, however, about how individuals cope with these events. This paper examines these events by using a multi-method pragmatic approach informed by coping theory. The results of two studies – a critical incident study and an experiment – serve to build and test, respectively, a theoretical model that posits that individuals use a variety of strategies when dealing with these events: they experience negative emotions, make external attributions, and adopt engagement coping strategies directed at solving the event, eventually switching to a disengagement coping strategy when they feel they have no control over the situation. Furthermore, users’ efforts may result in ‘accidental’ learning as they try to overcome the discrepant IT events through engagement coping. The paper ends with a discussion of the results in light of existing literature, future opportunities for research, and implications for practice.