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31.
以PIC16C711单片机为核心所研制的大功率直流电机控制器,通过硬件和软件的结合设计,使产品具有性能稳定、反应速度快,可靠性高、启动平稳及欠压、过流、刹车断电等多种保护功能。 相似文献
32.
Peer review feedback, developed to assist students with increasing the quality of group reports and developing peer review skills, was added to a master’s level Climate Change Policy and Planning unit. A pre- and post-survey was conducted to determine whether students found the process a valuable learning opportunity: 87% of students responding to the post-review survey indicated they saw benefit in both developing and receiving peer review feedback. Peer review design minimising the potential for plagiarism resulted in low levels of student concern surrounding plagiarism. Marks allocated by students were valid (consistent with the lecturer) and were generally reliable; however, distribution of marks had a higher variance where group report quality was low. Training on completing the peer review template could result in more reliable feedback. Consistent with the literature, the feedback developed during the peer review process focused on style and presentation preferentially to content. Seven out of eight group reports improved between report submissions, with all groups responding to peer review feedback. Peer review feedback and changes made to group reports indicated students had limited capacity to judge the quality of referencing and critical analysis. 相似文献
33.
Comparative Judgement (CJ) is an increasingly widely investigated method in assessment for creating a scale, for example of the quality of essays. One area that has attracted attention in CJ studies is the optimisation of the selection of pairs of objects for judgement. One approach is known as adaptive comparative judgement (ACJ). It has been claimed in the literature that ACJ produces very high reliability, often higher than can be obtained by conventional marking. Bramley showed by simulation that adaptivity can substantially inflate the apparent reliability in ACJ. The empirical study described here compared an adaptive with a non-adaptive CJ study using GCSE English essays. An all-play-all set of comparisons of a subset of the essays allowed the extent of scale inflation to be quantified: the reported adaptive reliability was 0.97 whereas the deflated value was 0.84. The value from the non-adaptive study was 0.72. However, the scale from the non-adaptive study correlated slightly higher with external variables, suggesting the non-adaptive study was no less valid than the adaptive one. 相似文献
34.
35.
宋力英 《黑龙江教育学院学报》2006,25(4):152-153
在高校外语教学中,四、六级外语统考已经成为大学生必须参加的一种考试。因为有了四级证,学生就业机会就会增大。但外语测试中存在着相当多的问题,如试题题型单一,猜测性较大,导致应试教学的产生,不能调动学生学习的自主性和积极性,也不能有效地考查出学生的实际水平,因此,我国的大学外语测试亟待改革。 相似文献
36.
柴油机的可维修性研究 总被引:1,自引:0,他引:1
张丽萍 《南通职业大学学报》2002,16(2):33-35
建立了柴油机具有共性的可维修系统的失效率模型,论述了柴油机的可维修性理论,探讨了其最佳维修周期的界定问题,给出了计算实例。该方法对其他系统的可维修性问题也具有普遍意义。 相似文献
37.
虚拟企业可靠性及其理论评价模型研究 总被引:2,自引:0,他引:2
综合虚拟企业及可靠性理论,在深入分析影响虚拟企业功能因素的基础上提出虚拟企业可靠性理论评价模型,为对虚拟企业及虚拟企业可靠性进行更加深入的研究打下了理论基础. 相似文献
38.
任务型语言测试观为大学英语测试(CET)提供了新的理论基础。在Bachman与Palmer的测试任务五特征基础上,创设了新题型设计基本模式,并依据该模式设计新题型对CET4测试进行了初步探索。信度和效度实证检验的结果表明,新题型组的均值虽因主观性试题量的增加而略低于旧题型组,但两者间并无显著性差异。而且新题型还呈现出同期效度值比旧题型高的态势:同时其信度系数也较高且具有显著的统计学意义。 相似文献
39.
R. K. Upadhyay S. K. Gaur V. P. Agrawal K. C. Arora 《European Journal of Engineering Education》2007,32(1):21-33
Quality assurance in engineering education is a multifaceted problem further augmented by the stakeholders of engineering education. Students, parents and employers are rightfully questioning the quality of the curriculum, the instructional delivery, the learning environment, accessibility to learning technologies and equipment, employability as well as the possibilities of lifelong learning and the improvement of knowledge (Karapetrovic 2002). The purpose of the study is, therefore, to identify the parameters that influence the quality of an engineering education system and develop an integrated model of hierarchical structuring and a concept map for pre-identified concept elements through a process of iterative-interactive consensus-driven methodology, as advocated by second-generation system design paradigm for evolving knowledge scenario of concepts related to quality engineering education. 相似文献
40.
Considering the uncertainty of material performance, geometric characteristic and analysis method, the analysis of statistical parameters of the resistance of cast ball-and-socket support joints and the reliability analysis are carried out by JC method (improved first-order second-moment method) based on the relevant experimental data. Results show that the resistance partial factor of the joint increases with the increase of the reliability index. The resistance partial factors are suggested corresponding to the reliability index under different load combinations. Moreover, the suggested resistance partial factor is adopted in reliability design, and it is found that the reliability index of the joint is larger than the target reliability index. The optimal load combination is the one in which live load plays an important control role. Finally, based on the suggested resistance partial factors, the reliability analysis of cast ball-and-socket support joints of a project is conducted. 相似文献