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Jacquetta Megarry David Hawkridge 《British journal of educational technology : journal of the Council for Educational Technology》1993,24(1):4-11
Co-production occurs when two or more institutions contribute funds and labour to the processes of making course components for distance teaching. The author summarises reasons for international co-production of multimedia distance-teaching courses and provides a checklist of questions that should be considered before entering upon such co-production.
The second half of the article consists of a composite case study based on the UK's Open University experience of international co-production. The paper ends with three questions: Is international co-production of this kind worth trying? Can the chances of success be made high enough by careful planning to justify risking capital in such ventures? Are other forms of collaboration more likely to be cost-effective? 相似文献
The second half of the article consists of a composite case study based on the UK's Open University experience of international co-production. The paper ends with three questions: Is international co-production of this kind worth trying? Can the chances of success be made high enough by careful planning to justify risking capital in such ventures? Are other forms of collaboration more likely to be cost-effective? 相似文献
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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
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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
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