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This paper reports research on the effects of variations in injection velocity and permeability on the heat transfer and flow through a highly porous medium between two horizontal parallel plates situated at constant distance with constant suction by the upper plate. Due to this type of variation in injection velocity and in permeability the flow becomes three dimensional. The governing equations are solved by adopting complex variable notations to obtain the expressions for the velocity and temperature field. The skin-friction along the main flow direction and rate of heat transfer are discussed with the help of graphs.  相似文献   
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本研究采用Sharma等人编制的<教师融合教育自我效能感量表>以及<融合教育忧虑量表>对上海市110名特殊教育学校教师以及213名普通学校教师进行了调查,结果发现:两类教师对开展融合教育具有一定水平的自我效能感;特殊教育学校教师的自我效能感要高于普通学校教师;普通学校教师在开展融合教学以及与他人合作方面的自我效能感普遍低于特殊教育学校教师,但在行为管理方面,则与特殊教育学校教师没有差异;两类教师对开展融合教育抱有中等水平的忧虑,且融合教育自我效能感与其忧虑水平存在显著负相关,教师对开展残疾学生教学的自信心水平越高,则对融合教育的忧虑越少.教师融合教育忧虑程度对自我效能感的方差贡献率超过50%以上.  相似文献   
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Recent research on principles of best practice for designing effective multimedia instruction has rarely taken into account students’ alternative conceptions, which are known to strongly influence learning. The goal of this study was to determine how well students of quantum mechanics could learn ‘vicariously’ by watching a student-tutor dialogue based on alternative conceptions. Two video treatments were created to summarize key aspects of quantum tunneling, a fundamental quantum mechanical phenomenon. One video depicted a student-tutor dialogue, incorporating many of the common alternative conceptions on the topic, and resolving inconsistencies in reasoning through discussion. The other presented the same correct physics material in an expository style without alternative conceptions. Second year physics students were randomly assigned to one of the two treatments and were tested before and after watching the video during a lecture. Results show a statistically significant (p < .01) advantage for the learners in the dialogue treatment (d = 0.71). Follow-up interviews of students yielded insight into the affective and cognitive benefits of the dialogue video.  相似文献   
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Evaluation of serum SOD and MDA level was done in 21 first episode renal stone formers, 9 recurrent stone formers, 20 patients with obstructive uropathy other than urolithiasis and 12 patients with urinary infection. Twenty-two healthy volunteers were taken as controls. The level of SOD in respective groups was 2.12±0.84, 2.78±0.85, 1.42±0.31, 1.98±0.70 and 2.32±0.62 units/ml and of MDA was 2.61±1.07, 2.69±1.15, 1.65±0.33, 1.33±0.34 and 1.55±0.48 n mol/ml respectively. The results indicate increased peroxidative stressin nephrolithiasis only. Since SOD level was normal in all groups, this increased peroxidative stress in nephrolithiasis should be due to factors other than this one.  相似文献   
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e-Government has emerged as a popular governance reform in recent years, to improve the productivity of the government and quality of services provided by it to various stake-holders. However, e-Government implementation is hampered by certain roadblocks such as lack of financial resources, lack of technical and soft skills, etc. Public–private partnership (PPP) has emerged as a viable model to counter these factors, apart from improving the economic sustainability of e-Government projects. PPP essentially implies sharing of risks and rewards of a venture. Successful implementation of PPP in e-Government requires the adoption of some key best practices, and incorporation of the learning obtained from previous PPP experiences. Four successful “PPP in e-Government” projects, implemented in Asia, are discussed to highlight the best practices and key learning obtained from each project. This is intended to highlight the necessary steps to be taken, especially in an Asian setting, to implement a successful PPP in e-Government.  相似文献   
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Variability in analytical performance of some analyte indicated the need of evaluation of quality plan of our laboratory. We tried to put the same degree of effort into our quality metrics as we put into the laboratory processes themselves. Application of six sigma methodologies improve the quality by focusing on the root causes of the problems in performance and analyzing by flowcharts, fishbone diagrams and other quality tools. Sigma metric was calculated for laboratory parameters for a period of 8 months during 2018–19. The analytes with poor sigma metric were free Thyroxine (FT3, FT4), Sodium, Calcium and Magnesium. Sigma metric of free Thyroxine (FT3, FT4), Sodium, Calcium and Magnesium were below 3. A road map for process improvement was designed with DMAIC (Define-Measure-Analyze-Improve-Control) model to solve the issue. Possible causes for low analytical performance of the particular analytes were depicted in Fishbone diagram. The Fishbone analysis identified the water quality issues with electrolyte analysis while high ambient temperature was culprit for poor assay performance of free Thyroxine. Sigma metric of the analytical performance was assessed once again after root cause analysis. Sigmametric showed marked improvement in control phase. Identification of problems led to reduction in non value added work leading to adequate resource utilization by addressing the priority issue. Therefore, DMAIC tool with Fish bone model analysis can be recommended as a well suited method for troubleshooting in poor performance of laboratory parameter.  相似文献   
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