Quantum algorithms: A?survey of some recent results     

Martin R?tteler 《Informatik - Forschung und Entwicklung》2006,55(3):3-20

Quantum algorithms are a field of growing interest within the theoretical computer science as well as the physics community. Surprisingly, although the number of researchers working on the subject is ever-increasing, the number of quantum algorithms found so far is quite small. In fact, the task of designing new quantum algorithms has been proven to be extremely difficult. In this paper we give an overview of the known quantum algorithms and briefly describe the underlying ideas. Roughly, the algorithms presented are divided into hidden subgroup type algorithms and in amplitude amplification type algorithms. While the former deal with problems of group-theoretical nature and have the promise to yield strong separations of classical and quantum algorithms, the latter have been proved to be a prolific source of algorithms in which a polynomial speed-up as compared to classical algorithms can be achieved. We also discuss quantum algorithms which do not fall under these two categories and give a survey of techniques of general interest in quantum computing such as adiabatic computing, lower bounds for quantum algorithms, and quantum interactive proofs.  相似文献   

Publisher and author partnerships: a changing landscape     

John J. Regazzi  Nicole A. Caliguiri 《Learned Publishing》2006,19(3):183-192

This article discusses the changing relationships of authors and publishers, the current trends and challenges they face, and the direction of these relationships in the future. As the STM publishing industry finds itself in the midst of significant technological and economic changes, this article provides background to these changes and looks at the key elements, including open access business development, institutional repository trends, and emerging public financing policies in the future.  相似文献   

体育明星作形象代言人推行品牌产品的战略效应分析   总被引：2，自引：0，他引：2  

乐仁油  王丹虹  庄德  徐志雄 《哈尔滨体育学院学报》2005,23(6)

运动鞋企业是晋江经济的支柱,其发展对晋江经济和体育产业的发展有着重要的意义。值此第七届晋江(国际)鞋业博览会之际,运用文献资料、调查访问、观察及网上查询等研究方法,并运用经济学、广告学等相关学科的一些原理,分析了福建晋江运动鞋企业聘请体育明星作形象代言人推行品牌建设的现状及存在的一些主要问题,并提出了进一步推动晋江运动鞋企业品牌建设的一些对策和建议,以便给当地政府及相关的决策者提供一些理论参考。  相似文献   

Indexing from A to Z,The H. W. Wilson Company. New York. Hans H. Wellisch, 1991, pp. xxvi, 461. isbn 0-8242-0807-2 £31.00 (cased) Available in the UK from Thompson Henry Ltd,London Rd,Sun-ningdale,Berks SL5 0EP.     

John A. Vickers 《Learned Publishing》1992,5(2):117-118

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Meta-analysis: a tool for medical and scientific discoveries.     

C L Schell  R J Rathe 《Bulletin of the Medical Library Association》1992,80(3):219-222

Medicine has made increasing use of meta-analysis, largely as a quantitative procedure for combining results of clinical trials. Meta-analysis begins with a comprehensive review of the literature. The next step is a systematic analysis of the quality and content of each study. Finally, results are combined statistically and conclusions are drawn from this new overview of the data. This paper presents a brief historical perspective on the use of meta-analysis in medicine with emphasis on the medical library. The authors conclude that in the future, medical librarians will play a significant role in the application of this useful technique.  相似文献   

Pre-season physiological characteristics of English first and second division soccer players.     

J A Davis  J Brewer  D Atkin 《Journal of sports sciences》1992,10(6):541-547

This investigation was undertaken in an effort to establish physiological characteristics of soccer players and to relate them to positional roles. A total of 135 footballers (age 24.4 +/- 4.6 years) were assessed for body mass, % body fat, haemoglobin, maximal oxygen uptake (VO2 max), leg power, anaerobic capacity and speed prior to an English league season. The sample included 13 goalkeepers, 22 full-backs, 24 centre-backs, 35 midfield players and 41 forwards. The goalkeepers were significantly heavier (86.1 +/- 5.5 kg; P < 0.01) than all groups except the centre-backs, had significantly higher estimated body fat percentages than centre-backs, forwards, midfield players (P < 0.01) or full-backs (P < 0.05), significantly lower estimated VO2 max values (56.4 +/- 3.9 ml kg-1 min-1; P < 0.01) and were slowest over 60 m (12.71 +/- 0.42 s). The midfield players had the highest predicted VO2 max values (61.4 +/- 3.4 ml kg-1 min-1), this being significantly greater (P < 0.05) than for the centre-backs. The forwards were the fastest group over 60 m (12.19 +/- 0.30 s), being significantly quicker than goalkeepers or centre-backs (P < 0.01) and full-backs (P < 0.05). Anaerobic power, as well as knee extensor torques (corrected for body mass) and extensor-flexor ratios, were similar between groups. No difference in estimated body fat percentage was observed between any of the outfield players, and haemoglobin concentrations were similar among players of all positions.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

Recent changes in the educational placement of deaf students     

A Schildroth 《American annals of the deaf》1988,133(2):61-67

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Chaos theory, informational needs, and natural disasters   总被引：2，自引：0，他引：2  

Timothy L. Sellnow  Matthew W. Seeger  Robert R. Ulmer 《Journal of Applied Communication Research》2002,30(4):269-292

This study applies chaos theory to a system-wide analysis of crisis communication in a natural disaster. Specifically, we analyze crisis communication during the 1997 Red River Valley flood in Minnesota and North Dakota. This flood, among the worst in modern American history, consumed entire metropolitan areas, displacing thousands of people. The conditions and decisions leading to the disaster, and the subsequent reactions are retraced. Communication related to river crest predictions (fractals), the shock at the magnitude of the crisis (cosmology episode), novel forms of reorganizing (self-organization), and agencies that aided in establishing a renewed order (strange attractors) are evaluated. Ultimately, we argue that preexisting sensemaking structures favoring rationalized, traditional views of a complex system led officials to make inappropriately unequivocal predictions and ultimately diminished the effectiveness of the region's crisis communication and planning.  相似文献   

每球得分制条件下影响一攻、防反关系的主要因素的研究——兼谈中国女排与世界女排的比较   总被引：3，自引：0，他引：3  

张桂青  张德广  钟霖 《中国体育科技》2002,38(5):27-31

通过对 1998年世界女子排球锦标赛、1999年世界杯女子排球赛与 1999年、2 0 0 0年全国女子排球甲级联赛的研究 ,对每球得分制条件下影响一攻和防反的主要因素进行论证。结果表明 :发球、一传效果、防守效果、不同风格打法和运动员心理素质是影响每球得分制条件下一攻、防反效果的主要因素 ;与世界强队相比 ,中国女子排球队在后排进攻方面存在着显著性差异  相似文献   

The laser printer as an agent of change     

Barbara A. Brannon 《Publishing Research Quarterly》2002,17(4):3-8

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