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981.
本文把与井简直接连通的大裂缝及井筒定义为“裂缝—井筒系统”,通过气体状态方程的变换和续流总量的计算,探索出井底大裂缝的容积及其储量的计算方法。 相似文献
982.
本文介绍一种利用原水中含有的无机盐,加入廉价的化学试剂除去饮用水中微量铀的简便方法。并对其除铀机理进行了探讨,证明除铀主要是以软化水过程中产生的氢氧化镁表面吸附共沉淀机理进行的。 相似文献
983.
Examined the 10 most cited articles published in the Psychological Bulletin over the past 4 decades. Seven of the 10 articles were methodologically oriented. A survey of the authors revealed that highly cited articles have an important message that goes beyond momentary fads, are broad in topic and intended audience, accessible, and well written. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
984.
D. T. Cambell and D. W. Fiske (1959) made the now-obvious statement that measures of the same variable made by different methods should agree (converge) and certainly should agree better than measures of different variables made by those several methods. Almost everyone accepted that statement, yet the multitrait–multimethod matrices published today show little or no improvement over the published examples cited in 1959. The article raised the conceptual problem of how a variable and its measurement should be linked and the methodological problem of clarifying the nature of methods and their effects. Given these unresolved problems, it is perhaps not surprising that the question of the appropriate statistical analysis of these matrices has also no consensual answer. Perhaps methods and traits or contents are so thoroughly intertwined that their interaction cannot be adequately analyzed. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
985.
Notes that 7 of the 10 top-cited articles in the Psychological Bulletin deal with methodological topics. One of these is the P. M. Bentler and D. G. Bonett (1980) article on the assessment of fit in covariance structure models. Some context is provided on the popularity of this article. In addition, a citation study of methodology articles appearing in the Bulletin since 1978 was carried out. It verified that publications in design, evaluation, measurement, and statistics continue to be important to psychological research. Some thoughts are offered on the role of the journal in making developments in these areas more accessible to psychologists. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
986.
Kosta Došen 《Journal of Logic, Language and Information》1992,1(3):173-201
The goal of this paper is to show how modal logic may be conceived as recording the derived rules of a logical system in the system itself. This conception of modal logic was propounded by Dana Scott in the early seventies. Here, similar ideas are pursued in a context less classical than Scott's.First a family of propositional logical systems is considered, which is obtained by gradually adding structural rules to a variant of the nonassociative Lambek calculus. In this family one finds systems that correspond to the associative Lambek calculus, linear logic, relevant logics, BCK logic and intuitionistic logic. Above these basic systems, sequent systems parallel to the basic systems are constructed, which formalize various notions of derived rules for the basic systems. The deduction theorem is provable for the basic systems if, and only if, they are at least as strong as systems corresponding to linear logic, or BCK logic, depending on the language, and their deductive metalogic is not stronger than they are.However, though we do not always have the deduction theorem, we may always obtain a modal analogue of the deduction theorem for conservative modal extensions of the basic systems. Modal postulates which are necessary and sufficient for that are postulates of S4 plus modal postulates which mimic structural rules. For example, the modal postulates which Girard has recently considered in linear logic are necessary and sufficient for the modal analogue of the deduction theorem.All this may lead towards results about functional completeness in categories. When functional completeness, which is analogous to the deduction theorem, fails, we may perhaps envisage a modal analogue of functional completeness in a modal category, of which our original category is a full subcategory. 相似文献
987.
信息迅猛发展的今天,多媒体计算机辅助教学已深入课堂,现代教育技术班班通的巧妙运用,更是打破了"一个黑板+一只粉笔"的原有的传统教学模式。"班班通"是通过多媒体使学校每个班级具备了与外界进行交流的能力,实现信息技术与学科日常教学的有效整合,促进教师语文教学方式和学生语文学习方式的变革,最终促进学生的发展。利用班班通网络资源与语文课堂学习相结合具有创设特定情境,激发学生的学习兴趣、化繁为简,化难为易,让学生轻松快乐学习、阅读速度加快,阅读量增多、学生深入理解文本等优势,本文结合语文阅读教学、作文教学、读写教学总结了在探索中运用"班班通"的经验和做法,创造了师生双赢的局面。 相似文献
988.
The Swedish Fire Research Board and the U.S. Federal Emergency Management Agency are sponsoring a project to further the understanding of the basic mechanisms involved, as well as to support the development of standards for and to seek ways of improving the performance of portable fire suppression systems used by fire departments.This paper describes a physically based computer model developed to simulate one aspect of the problem: the manual suppression of postflashover fires. This includes: (1) an overview of the physical basis behind the model; (2) a comparison of model predictions with available experimental data, and (3) an analysis of fire suppression effectiveness using the model.The analysis concludes that, when direct access and extinguishment of the burning fuel is not possible, improved fire control occurs with water sprays having a Rosin-Rammler distribution of droplet sizes with volume-median-drop diameters in the 0.15 to 0.35 mm range. This agrees with available experimental data. It is also shown that fire fighting venting and standoff distance requirements may lead to more severe fires requiring more water for control; although venting and water spray induced air/gas flow also serve to channel hot steam and gases away from the fire fighter adding to his safety. The analysis also shows that allowing higher gas and surface temperatures at fire control through improved fire fighter protective clothing and equipment design reduces water flow rate requirements. Additional experimental work is recommended before all these conclusions are considered definitive.
Reference: L. M. Pietrzak and G. A. Johanson, Directions for Improving Manual Fire Suppression Using a Physically Based Computer Simulation,Fire Technology, Vol. 22, No. 3, August, 1986, p. 184. 相似文献
989.
Reexamines experiments on learned helplessness that have been interpreted previously as involving a solitary person experiencing uncontrollable and inescapable events. It is suggested that the belief that the outcomes are uncontrollable precludes the possibility that control of the outcomes can be transferred to the experimental Ss. An alternative interpretation is that the outcomes in learned helplessness experiments, rather than being uncontrollable, are controlled by the experimenter. Helplessness could be reduced by transferring this control to Ss, giving them control over their contingencies. This analysis has implications regarding both the accuracy of depressed people's perceptions and the desirability of making depressed people perceive an internal locus of control. It is further suggested that depressed people should have more control over their contingencies. (34 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
990.