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M D Bonham 《Bulletin of the Medical Library Association》1990,78(2):119-123
In the twenty years of its existence, BIREME has grown and evolved to meet the increasing information needs of health professionals in Latin America and the Caribbean. Recent emphasis has been on the adoption of new methods based on information technologies (including microcomputers, CD-ROMs, and advanced telecommunications) to improve and enhance services. Services discussed are bibliographic control, bibliographic searches, document delivery, selective dissemination of information (SDI), training, and publications. 相似文献
885.
V. D. Shadrikov 《Higher Education in Europe》1989,14(4):57-62
This article reviews the Soviet proposal for the establishment of a University of the Peoples of Europe. It outlines the necessary conditions and the arrangements which must be made so that serious planning can get underway. It reiterates the proposed general purposes and objectives of the university and the proposals which have been made with regard to its administrative structure, organization, and working methods. If successfully established, the University of the Peoples of Europe would not only contribute to the solution of all‐European and world problems but would serve as a milestone on the road to European intellectual integration. 相似文献
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An overview of cricket ball swing 总被引:1,自引:0,他引:1
Rabindra D. Mehta 《Sports Engineering》2005,8(4):181-192
The aerodynamic properties of a cricket ball have intrigued cricket players and spectators for years, arguably since the advent
of the game itself. The main interest is in the fact that the ball can follow a curved flight path that may not always be
under the control of the bowler. The basic aerodynamic principles responsible for the nonlinear flight or ‘swing’ of a cricket
ball were identified decades ago and many papers have been published on the subject. Over the last 25 years or so, several
empirical investigations have also been conducted on cricket ball swing, which revealed the amount of attainable swing and
identified the parameters that affect it. Those findings are reviewed here with emphasis on phenomena such as late swing and
the effects of humidity on swing. The relatively new concept of ‘reverse swing’, how it can be achieved in practice, and the
role in it of ‘ball tampering’, are also discussed in detail. In particular, the ability of some bowlers to effectively swing
an old ball in the conventional, reverse and the newly termed ‘contrast’ swing mode is addressed. A discussion of the ‘white”
cricket ball used in the 1999 and 2003 World Cup tournaments, which supposedly possesses different swing properties compared
to a conventional red ball, is also included. This is a current overview of cricket ball swing rather than a detailed review
of all research work performed on the topic. The emphasis is on presenting scientific explanations for the various aerodynamic
phenomena that affect cricket ball swing on a cricket ground. 相似文献
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据法国著名保险集团公司ARGOS提供的材料,文物走私成了仅次于毒品走私的全球第二大非法行业。大约每一小时就会在法国或意大利发生一起文物盗窃案。 相似文献
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