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121.
笔者结合多年来的教学经验和体会,发现计算机辅助教学(CAI)与问题式学习(PBL)相结合的教学模式在医学免疫的教学中发挥着非常重要的作用。 CAI技术可增加课堂信息量,节约时间,使教学内容生动、形象。 PBL教学则可以激发学生的学习热情和求知欲望,使学生动手能力、文献查找能力、分析问题和解决问题能力等综合素质得到提高。二者的结合可以使枯燥的教学内容变得生动、活泼,从而达到理想的教学效果。 相似文献
122.
先秦时期,“比及”从跨层结构发展出介词功能,这一功能一直沿用至清代。介词功能在元代演变出了表示假设、让步、选择以及因果关系的连词功能,不过连词功能多用于元代,明清少见,到现代汉语中完全绝迹。但“比及”到现代汉语中又衍生出了动词用法,表示“比拟,与……相比”之义,这一动词功能在网络新闻用语中有进一步扩大的趋势。 相似文献
123.
黄芩是河北承德的道地药材,虫害是影响其产量和品质的重要因素之一,本文总结了北方地区黄芩主要虫害的种类、识别要点、发生特点及综合防治技术。 相似文献
124.
王定康 《毕节师范高等专科学校学报》2009,(11):68-70
许慎在《说文解字》中释“顺”为“理也”,当为“顺”之引申义,“顺”之本义应为“合乎自然次序”。依据有三:第一,参照“顺”的古文形体,比合“川”、“页”两意,可推求“顺”之本义;第二,“顺”之本义在古代文献资料中用例颇多,现代方言俗语亦可佐证;第三,“顺”的这一本义是其整个词义系统的源头和总纲。 相似文献
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In petrochemical plant, the in-operation repairing is usually a repairing strategy with pressured inoperation repairing for avoiding huge economic losses caused by unplanned shutdown when some slight local leakage happens in pipes. This paper studies the effects of repairing strategies on the failure probability of the pipe systems in process industries based on the time-average fault tree approach, especially the in-operation repairing strategies including pressured in-operation repairing activities. The fault tree model can predict the effect of different repairing plans on the pipe failure probability, which is significant to the optimization of the repairing plans. At first pipes are distinguished into four states in this model, i.e., successive state, flaw state, leakage state and failure state. Then the fault tree approach, which is usually applied in the studies of dynamic equipment, is adopted to model the pipe failure. Moreover, the effect of pressured in-operation repairing is also considered in the model. In addition, this paper proposes a series of time-average parameters of the fault tree model, all of which are used to calculate node parameters of the fault tree model. At last, a practical case is calculated based on the fault tree model in a repairing activity of pipe thinning. 相似文献
128.
William J. Sersen 《美中教育评论》2011,(3):339-345
In this study, we examined the likelihood of a TAME (extended technology acceptance model), in which the interrelationships among computer self-efficacy, perceived usefulness, intention to use and self-reported use of computer-mediated technology were tested. In addition, the gender- and age-invariant of its causal structure were evaluated. The data were collected from a self-reported questionnaire administered to 477 administrative staff of a public university in Malaysia. The results of structural equation modeling supported the adequacy of TAME. Although the TAME's causal structure was applicable to both male and female staff, age group appeared to moderate the structural relationships among the constructs of interest. 相似文献
129.
研究了SOA的基本概念和体系结构,分析了将Web Service作为SOA实现技术的不足之处,阐明了SCA/SDO编程模型的优势,并针对高校信息化建设的现状,提出了基于SCA/SDO编程模型,对高校信息系统进行集成的SOA架构模型。 相似文献
130.
In early research, capture and manipulation of particles were mainly achieved by means of light, electricity and plasma in micro-fabficaton and micro-assembly. A new method is proposed using micro-water jet to form water tweezers to capture solid particles and implement position control of micro-particles. This paper analyzes the basic prin- ciple of water tweezers, and the discrete element method and smoothed particle hydrodynamics method are employed to establish a solid-liquid coupling model used in analyzing the trapping mechanism. A flow field model is set up to simulate dynamic characteristic of water tweezers based on computa- tional fluid dynamics (CFD). Selection of boundary conditions, initial guess, solver control and convergence strategies of the model are discussed. Velocity and pressure of streamline are predicted and discussed under certain input conditions. Simu- lation results demonstrate that it is an efficiently theoretical method to eventually trap solid particles by water tweezers. 相似文献