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解放前我国学者对新疆石油地质的调查和研究 总被引:1,自引:0,他引:1
20世纪初,随着近代地质学在中国的形成和发展,一些学者开始了对新疆石油地质的调查和研究,30年代末以前,翁文灏,章鸿钊等学者利用文献和间接获得的资料,对新疆石油资源进行了宏观考察和若干重要油苗的地质研究;40年代开始,黄汲清等地质家在新疆进行实地考察,对独山子油田进行了详细研究,并在南北疆部分地区进行了路线性石油地质调查。 相似文献
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A. Cau R. Hale J. Dimitrov H. Zedan B. Moszkowski M. Manjunathaiah M. Spivey 《Design Automation for Embedded Systems》2002,6(4):367-399
We describe a compositional framework, together with its supporting toolset, for hardware/software co-design. Our framework is an integration of a formal approach within a traditional design flow. The formal approach is based on Interval Temporal Logic and its executable subset, Tempura. Refinement is the key element in our framework because it will derivefrom a single formal specification of the system the software and hardware parts of the implementation, while preserving all properties of the system specification. During refinement simulation is used to choose the appropriate refinement rules, which are applied automatically in the HOL system. The framework is illustrated with two case studies. The work presented is part of a UK collaborative research project between the Software Technology Research Laboratory at the De Montfort University and the Oxford University Computing Laboratory. 相似文献
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The development of verbal and spatial working memory was investigated with an interference paradigm. Memory spans were obtained from 3 groups (8-, 10-, and 19-yr olds) under 6 different conditions: Two primary memory tasks (1 verbal, 1 spatial) were administered in isolation and in conjunction with 2 versions of a secondary task. The primary tasks required recalling a series of visually presented digits and recalling the locations of Xs in a series of visually presented grids. The secondary tasks required reporting the color of the stimuli as they were presented using either a verbal or a spatial response. Analyses revealed that all age groups showed domain-specific interference (i.e., interference by a secondary task from the same domain as the primary task), but only the 8-yr-olds also showed nonspecific interference (i.e., interference by a secondary task from a domain different than the primary memory task), suggesting that at least some executive functions do not reach adult levels of efficiency until approximately age 10. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
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Coulter counting and light diffraction techniques were successfully applied to the characterisation of the droplet concentration and size distribution in camphene-water and cyclohexane-water emulsions. Both of these techniques required a dilution of the emulsion prior to analysis, and it was found that the destabilizing effect on the droplets of such dilution could be overcome by performing the analyses at temperatures below the melting point of the oil phase. The storage stability of the camphene-water samples at 60 degrees C was reasonably good with a 5-20% change in the investigated parameters over a 24 h period. At room temperature camphene-water samples left to stand undisturbed were unaffected after 24 h, while continuous mixing of the emulsion on a roller board brought about a rapid amalgamation of the particles into larger aggregates. This fusion process was fully described only with the light diffraction analysis due to the broader measuring range of this technique. However, analysing emulsions with a droplet size range covered by both techniques gave identical results. 相似文献
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