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51.
It looks like 2000 could be a big year for public key infrastructure (PKI). Five leading vendors this week announced the formation of the PKI Forum with the intention of moving the technology forward as an E-commerce enabler.  相似文献   
52.
53.
Ed Blakey 《Natural computing》2011,10(4):1245-1259
Unconventional computers—which may, for example, exploit chemical/analogue/quantum phenomena in order to compute, rather than electronically implementing discrete logic gates—are widely studied in both theoretical and practical contexts. One particular motivation behind unconventional computation is the desire efficiently to solve classically difficult problems—we recall chemical-computer attempts at solving NP -complete problems such as the Travelling Salesperson Problem—, with computational complexity theory offering the criteria for judging this efficiency. However, care must be taken here; conventional (Turing-machine-style) complexity analysis is not always appropriate for unconventional computers: new, non-standard computational resources, with correspondingly new complexity measures, are often required. Accordingly, we discuss in the present paper various resources beyond merely time and space (and, indeed, discuss various interpretations of the term ‘resource’ itself), advocating such resources’ consideration when analysing the complexity of unconventional computers. We hope that this acts as a useful starting point for practitioners of unconventional computing and computational complexity.  相似文献   
54.
A pioneer of anti-spam software and E-mail programs has formed partnerships with a number of leading industry players to combat the growing problem of spam, or unsolicited E-mail.  相似文献   
55.
A new disaster recovery initiative is just being launched in the US by 20 vendors. The vendors including Dell Computer, Hewlett-Packard, IBM and Sun Microsystems and led by Quantum Systems have launched Prove-IT to offer the small and medium-sized business continuity and archiving services. Prove-IT is aimed at companies with annual revenue between $50 million and $500 million. There are plans to expand the initiative to Europe, according to Margaret Pereira, spokesperson for Quantum, but she gave “six months to a year” as a time frame for when the programme may move overseas.  相似文献   
56.
2003.3/下半月 www.eepw.com.cn电子产品世界本文给出一个简单、完整的传感器基测量系统设计,该系统是用测量两个光束隔断的时间来测量运动物体的速度。此设计包括显示和状态指示器、时间保持和控制功能所需的所有数字逻辑以及连接提供光感测功能的IR(红外)LED和光二极管所必须的模拟信号处理。系统测量经过时间范围是毫秒~分钟量级。本系统有4个主要的子系统(见图1):用户接口,传感器接口/接收器,计数器/显示逻辑和主机控制逻辑。用户接口由7位LED数字显示(显示经过时间)、几个状态LED和两个按钮开关(RESE…  相似文献   
57.
Three studies were conducted to determine whether physical attractiveness (PAT) is related to subjective well-being (SWB). In the first study (N?=?221), unselected students were photographed and videotaped. In the second study (N?=?131), participants were selected on the basis of extremes in PAT, and in the third study (N?=?155), participants were preselected for extreme scores on SWB. Correlations between SWB and PAT varied from .03 to .33. In Study 1 the mean correlation between PAT and SWB was .13. When appearance enhancers (hair, clothing, and jewelry) were covered or removed in Studies 2 and 3, the correlation between PAT and SWB dropped, suggesting that part of the SWB–PAT relation might be due to happier people doing more to enhance their beauty. The impact of PAT on SWB may be mitigated by the fact that others agree on a target's PAT at only modest levels. It was found that self-perceptions of PAT were correlated with both one's objective PAT and one's SWB. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
58.
Process flight simulation tools can help managers understand the dynamics of new processes and technologies before they are introduced. This article tells how these exploratory tools can be used for IS project management, simple modeling of the software process, and modeling the dynamics of the IS organization in transition.  相似文献   
59.
Literally, the word compliance suggests conformity in fulfilling official requirements. This paper presents the results of the analysis and design of a class of protocols called compliant cryptologic protocols (CCPs). The paper presents a notion for compliance in cryptosystems that is conducive as a cryptologic goal. CCPs are employed in security systems used by at least two mutually mistrusting sets of entities. The individuals in the sets of entities only trust the design of the security system and any trusted third party the security system may include. Such a security system can be thought of as a broker between the mistrusting sets of entities. Published online: 15 November 2002  相似文献   
60.
The main impetus for the SPRinG (social pedagogic research into grouping) project was to address the wide gap between the potential of group work and its limited use in schools. It is an ambitious project that developed key principles and strategies to improve the effectiveness of group work in everyday primary classes and across a whole school year. On-the-spot and video-based systematic observations showed more active, sustained engagement, more connectedness, and more higher order inferential joint reasoning within SPRinG groups than in control comparisons. The authors argue that group work can be successfully implemented into everyday school classrooms and improve pupil interactions, provided teachers take time to train pupils in the skills of group working. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
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