Achieving CIM Through Mastery of the Basics

Many manufacturers are considering computer-integrated manufacturing in their search for a competitive edge. However, before automating inefficient processes, companies should first examine and streamline their current methods of operation.     

Biometrics: Future Abuses

Where will the inevitable global mass collation of sensitive biometric data be stored?Starting with a case history from the Transportation Security Administration (TSA), this article provides an introduction to the delicate relationship between biometric recognition and personal privacy. While technologies such as iris recognition are achieving high levels of intrinsic reliability, the spectre of their abuse lurks just around the corner.     

Achieving Robustness and Minimizing Overhead in Parallel Algorithms Through Overlapped Communication/Computation

One of the major goals in the design of parallel processing machines and algorithms is to achieve robustness and reduce the effects of the overhead introduced when a given problem is parallelized or a fault occurs. A key contributor to overhead is communication time, in particular when a node is faulty and another node is substuiting for its operation. Many architectures try to reduce this overhead by minimizing the actual time for a communication to occur, including latency and bandwidth figures. Another approach is to hide communication by overlapping it with computation assuming that the computation is the most prominent factor. This paper presents the mechanisms provided in the Proteus parallel computer and its effective use of communication hiding through overlapping communication/computation techniques with and without the presence of a fault. These techniques are easily extended for use in compiler support of parallel programming. We also address the complexity (or rather simplicity) in achieving complete exchange on the Proteus Machine.     

Robust Reductions

We continue the study of robust reductions initiated by Gavaldà and Balcázar. In particular, a 1991 paper of Gavaldà and Balcázar [7] claimed an optimal separation between the power of robust and nondeterministic strong reductions. Unfortunately, their proof is invalid. We re-establish their theorem. Generalizing robust reductions, we note that robustly strong reductions are built from two restrictions, robust underproductivity and robust overproductivity, both of which have been separately studied before in other contexts. By systematically analyzing the power of these reductions, we explore the extent to which each restriction weakens the power of reductions. We show that one of these reductions yields a new, strong form of the Karp—Lipton theorem. Received November 1997, and in final form March 1999.     

Non-Uniform Reductions

We study properties of non-uniform reductions and related completeness notions. We strengthen several results of Hitchcock and Pavan (ICALP (1), Lecture Notes in Computer Science, vol. 4051, pp. 465–476, Springer, 2006) and give a trade-off between the amount of advice needed for a reduction and its honesty on NEXP. We construct an oracle relative to which this trade-off is optimal. We show, in a more systematic study of non-uniform reductions, among other things that non-uniformity can be removed at the cost of more queries. In line with Post’s program for complexity theory (Buhrman and Torenvliet in Bulletin of the EATCS 85, pp. 41–51, 2005) we connect such ‘uniformization’ properties to the separation of complexity classes.     

BAR-BGP:基于备份通告和恢复转发的可靠域间路由

Internet逐渐成为通信基础设施,而BGP协议通过触发缓慢的反应式收敛过程应对网络拓扑和策略的变化,大量测量表明收敛过程中瞬时不可达以及环路造成很高的报文丢失率,难以支持延迟、中断敏感的应用.BAR-BGP采用了将预获取备份地址与反应式动态计算路径结合的方法以应对瞬时失效带来的转发中断.通告备份AS以较低的开销获得瞬时失效后可将报文封装转发到可行中继节点;在收敛过程中使用失效根源信息消除环路;并当无备份AS可用时,采用恢复转发模式进一步降低转发中断.通过使用Internet-like拓扑模拟实验证明了BAR-BGP有效避免收敛过程的瞬时失效与转发中断,增强网络可靠性.     

中国生物特征识别市场前景看好

中国科学院副秘书长谭铁牛说:中国的生物特征识别市场保持每年50%的增长率,并且在2010年将拥有3倔人民币市场占有量.谭铁牛还说:指纹依然是最广泛的生物特征识别技术,但是其他的技术如虹膜识别、人脸识别等技术也渐渐得到推广应用.     

Biometrics in Identity Management Systems

Biometric technology - the automated recognition of individuals using biological and behavioral traits - has been presented as a natural identity management tool that offers "greater security and convenience than traditional methods of personal recognition." Indeed, many existing government identity management systems employ biometrics to assure that each person has only one identity in the system and that only one person can access each identity. Historically, however, biometric technology has also been controversial, with many writers suggesting that biometrics invade privacy, that specific technologies have error rates unsuitable for large-scale applications, or that the techniques "are useful to organizations that regulate the individual, but of little use where the individual controls identification and authorization." Here, I address these controversies by looking more deeply into the basic assumptions made in biometric recognition. I'll look at some example systems and delve into the differences between personal identity and digital identity. I'll conclude by discussing how those whose identity is managed with biometrics can manage biometric identity management.     

Biometrics: truths and untruths

Biometrics is a scientific method used in technology to authenticate access to given critical resources. This system is based on the recognition of specific extremely personal ‘distinguishing marks’, that is to say unique physiological and behavioral traits. At a time when there is talk of ‘certainty of access’, that is to say of univocal authentication of the users of a service, biometrics could provide a valid alternative.     

基于人耳生物特征的身份识别

人耳识别技术的研究与应用在个体生物特征识别范围属于一种新的尝试.本文首先讨论了人耳识别技术的可行性及其特点,介绍了基于二维灰度图像、3D深度图像和耳纹图像的人耳自动识别方法,并重点对静态人耳图像识别方法进行了总结.最后针对人耳识别技术中的一些关键性问题,如人耳特征信息的提取、人耳图像的遮挡与缺损处理、人耳识别方法以及人耳图像库的构建进行了探讨,提出一些解决问题的思路.     

Developmental Tools - Synthetic Biometrics

In this paper, we draw an analogy to a field which has a great deal in common with computer vision. This field is that of biometric technologies, which attempt to generate computer models of humans' appearance or behavior with a view to reliable personal identification. Computer graphics, in its turn, can be likened to biometric synthesis - rendering biometric phenomena from their corresponding computer models. For example, we could generate a synthetic face from its corresponding computer model. Such a model could include muscular dynamics to model the full gamut of human emotions conveyed by facial expressions     

生物特征识别技术中的活体确认

总结和分析了活体确认技术的现状,指出了存在的一些重要问题,重点讨论了它在指纹识别中的研究进展,并在判别信号检测区域的选择,判别信号的提取和整理、消除信号特征冗余和BP神经网络分类等方面提出了有效的改进算法和方案,指出了可靠的判决特征的选择方向。     

三维生物特征识别进展

迄今为止的绝大多数生物特征识别系统都是基于二维图像的。而成像过程中必有物体三维信息缺失,这使得单纯基于二维图像的特征识别研究在经历了一段时间的发展后,停滞不前。越来越多的研究者开始关注三维生物特征识别技术。利用三维生物特征数据可以充分发掘深度、曲率信息并较好地处理光照、姿态的影响,从而进一步提高识别率。论文综述了该领域当前的国内外研究现状,并探讨了面临的主要困难以及未来的发展方向。