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V. Smetáček 《Information processing & management》1979,15(4):173-177
All live systems acquire and use knowledge to ensure appropriate efficiency in the mutual intercourse with the surrounding environment. Knowledge can be communicated only when the subject's internal model of the object of reality is objectified by means of a certain set of physical signs. Such an externalized model, a communicate, is to be accepted, adequately understood and evaluated by other relevant live systems. The information value of a communicate is therefore a function not only of the communicate itself but of the needs, aims, expectations and possibilities of relevant live systems as well. The information value of the same communicate can vary within a set of those systems. The determination of regularities in the relations between the information value of communicates, their content similarity and distinctive features of live systems producing and using them is a problem for experimental and empirical studies. 相似文献
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This paper examines Brazil’s Sector Funds, an emerging research and development policy that seeks to increase public-private research collaboration. The first section sets the context of the ‘policy problem’. The second section discusses the policy’s implementation, and discusses its likely implications for Brazil and beyond. 相似文献
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2002年,教育部下发了《全国普通高等院校体育课程指导纲要》,并要求2003年开始在全国普通高等学校中施行。《纲要》指出,把“健康第一”的指导思想作为确定课程内容的基本出发点。高等学校的学生大多来自全国各地,他们的体育基础、体质状况、爱好、家庭条件以及生活环境等都存在较大的差异。而现行的统一计划、统一操作的体育教学模式难以达到最佳效果,要改进这一现状,就要遵循体育课程内在的规律,给学生以尽可能大的选择空间,并由教师指导学生选择最适合于自己的体育方式,以达到提高健康水平的最佳效果。 相似文献
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Electrosprays are a powerful technique to generate charged micro/nanodroplets. In the last century, the technique has been extensively studied, developed, and recognized with a shared Nobel price in Chemistry in 2002 for its wide spread application in mass spectrometry. However, nowadays techniques based on microfluidic devices are competing to be the next generation in atomization techniques. Therefore, an interesting development would be to integrate the electrospray technique into a microfluidic liquid-liquid device. Several works in the literature have attempted to build a microfluidic electrospray with disputable results. The main problem for its integration is the lack of knowledge of the working parameters of the liquid-liquid electrospray. The “submerged electrosprays” share similar properties as their counterparts in air. However, in the microfluidic generation of micro/nanodroplets, the liquid-liquid interfaces are normally stabilized with surface active agents, which might have critical effects on the electrospray behavior. In this work, we review the main properties of the submerged electrosprays in liquid baths with no surfactant, and we methodically study the behavior of the system for increasing surfactant concentrations. The different regimes found are then analyzed and compared with both classical and more recent experimental, theoretical and numerical studies. A very rich phenomenology is found when the surface tension is allowed to vary in the system. More concretely, the lower states of electrification achieved with the reduced surface tension regimes might be of interest in biological or biomedical applications in which excessive electrification can be hazardous for the encapsulated entities. 相似文献
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Abstract The aim of this study was to examine the effect of positioning on the correctness of decision making of top-class referees and assistant referees during international games. Match analyses were carried out during the Fédération Internationale de Football Association (FIFA) Confederations Cup 2009 and 380 foul play incidents and 165 offside situations were examined. The error percentage for the referees when indicating the incidents averaged 14%. The lowest error percentage occurred in the central area of the field, where the collaboration of the assistant referee is limited, and was achieved when indicating the incidents from a distance of 11-15?m, whereas this percentage peaked (23%) in the last 15-min match period. The error rate for the assistant referees was 13%. Distance of the assistant referee to the offside line did not have an impact on the quality of the offside decision. The risk of making incorrect decisions was reduced when the assistant referees viewed the offside situations from an angle between 46 and 60°. Incorrect offside decisions occurred twice as often in the second as in the first half of the games. Perceptual-cognitive training sessions specific to the requirements of the game should be implemented in the weekly schedule of football officials to reduce the overall error rate. 相似文献