非傅立叶模型层状复合陶瓷结构热传导分析     

张士元  郑百林  贺鹏飞 《福建工程学院学报》2009,7(1)

用非傅立叶热传导模型分析层状复合陶瓷结构的温度场,并与单热涂层结构的结果进行比较,同时进一步研究了夹层热物理性能参数对温度场的影响.研究表明:夹层可以有效地减缓内部结构的温度变化,夹层热物理性能参数(如:松弛时间、声速)对结构层的温度场有明显影响.  相似文献   

Relations between EFL teachers’ formal knowledge of grammar and their in-action mental models of children's minds and learning     

Orly Haim  Sidney Strauss  Dorit Ravid 《Teaching and Teacher Education》2004,20(8):861

We studied the relations between English as a foreign language teachers’ grammar knowledge and their in-action mental models (MMs) of children's minds and learning. The grammar knowledge we examined was English wh-constructions. A total of 74 teachers completed an assessment task and were classified to have deep, intermediate or shallow knowledge. Ten teachers (five with deep and five with shallow level) were videotaped teaching wh-questions. The data were analysed qualitatively to determine the teachers’ MM, and then quantitatively to test similarities/differences in their MM's expression. The findings revealed an identical MM among all teachers that is expressed differently as a function of knowledge level.  相似文献   

教育技术领域的内涵、外延及其探究方法——访教育技术学知名专家亚历山大·罗米斯佐夫斯基博士     

方柏林 《开放教育研究》2008,14(6)

[编者按] 亚历山大·罗米斯佐夫斯基博士(Alexander Romiszowski)是美国雪城大学教学设计、开发和评估系的教授,国际知名的教育技术学家,远程教育理论家和思想家,他的著作在很大程度上影响了教育技术和教学设计领域的界定.  相似文献   

Changes in swimming technique during time to exhaustion at freely chosen and controlled stroke rates     

Alberty M  Potdevin F  Dekerle J  Pelayo P  Gorce P  Sidney M 《Journal of sports sciences》2008,26(11):1191-1200

The aim of this study was to assess technical changes during constrained swimming in time-to-exhaustion tests. Ten swimmers of national standard performed a maximal 400-m front crawl and two sets of exhaustion tests at 95%, 100%, and 110% of mean 400-m speed. In the first set (free), swimmers had to maintain their speeds until exhaustion and mean stroke rate was recorded for each test. In the second set (controlled), the same speed and individual corresponding stroke rate were imposed. The durations of the exhaustion tests, relative durations of the stroke phases, and arm coordination were analysed. For each speed in the "controlled" set, the exhaustion tests were shorter. Moreover, variables were consistent, suggesting a stabilization of stroke technique. Under the free condition, stroke rate increased to compensate for the decrease in stroke length. At the same time, swimmers reduced the relative duration of their non-propulsive phases in favour of the propulsive phases. Thus, swimmers changed their arm coordination, which came close to an opposition mode. These two constraints enable swimmers both to maintain their stroking characteristics and develop compensatory mechanisms to maintain speed. Moreover, stroke rate can be seen as a useful tool for controlling arm technique during paced exercise.  相似文献   

Confusion and complex learning during interactions with computer learning environments     

Blair Lehman  Sidney D'Mello  Art Graesser 《The Internet and Higher Education》2012,15(3):184-194

Folk wisdom holds that being confused is detrimental to learning. However, research on emotions and learning suggest a somewhat more complex relationship between confusion and learning outcomes. In fact, it has been proposed that impasses that trigger states of cognitive disequilibrium and confusion can create opportunities for deep learning of conceptually difficult content. This paper discusses four computer learning environments that either naturally or artificially induce confusion in learners in order to create learning opportunities. First, an Intelligent Tutoring System called AutoTutor that engenders confusion through challenging problems and vague hints is described. The remaining three environments were specifically designed to induce confusion through a number of different interventions. These interventions include device breakdowns, contradictory information, and false feedback. The success and limitations of confusion induction and the impact of confusion resolution on learning are discussed. Potential methods to help learners productively manage their confusion instead of being hopelessly confused are also discussed.  相似文献   

Dynamics of affective states during complex learning     

Sidney D’Mello  Art Graesser 《Learning and Instruction》2012,22(2):145-157

We propose a model to explain the dynamics of affective states that emerge during deep learning activities. The model predicts that learners in a state of engagement/flow will experience cognitive disequilibrium and confusion when they face contradictions, incongruities, anomalies, obstacles to goals, and other impasses. Learners revert into the engaged/flow state if equilibrium is restored through thought, reflection, and problem solving. However, failure to restore equilibrium as well as obstacles that block goals trigger frustration, which, if unresolved, will eventually lead to boredom. The major hypotheses of the model were supported in two studies in which participants completed a 32-35 min tutoring session with a computer tutor. Their affective states were tracked at approximately 110 points in their tutoring sessions via a retrospective affect judgment protocol. Time series analyses confirmed the presence of confusion-engagement/flow, boredom-frustration, and confusion-frustration oscillations. We discuss enhancements of the model to address individual differences and pedagogical and motivational strategies that are inspired by the model.  相似文献   

The basis of liability for broadcasting defamatory remarks     

Sidney A. Diamond 《广播与电子媒介杂志》2013,57(1):40-43

In an article that appeared in Winter 1958–1959 issue of the Journal of Broadcasting, Profesor Gordon Greb added a new contender for the title of “oldest station in the nation.”; As a result, KQW has joined KDKA, WHA and WWJ as a candidate for the honor of primacy in American radio broadcasting. Although Greb's article created as much interest and controversy as any that has appeared in the Journal, it did not—and could not—still the confidence of the other claimants.

In the instant article, Mr. R. Franklin Smith does the field of historical radio research a service by setting forth, for the first time, a logical set of criteria by which to judge these conflicting claims. To illustrate he has utilized early records of WHA. Using these criteria, it is shown that WHA cannot claim to have been a true broadcasting station before the latter part of 1920. Comparison of the claims of the several contenders is outside the scope of this article. However, it would be extremely interesting if these criteria were applied to the conflicting claims by persons having access to the detailed station records and other data necessary for thorough analysis.

Perhaps Mr. Smith has given us the impetus and the tools necessary for determining which station really was the “oldest in the nation.”  相似文献   

By Comparison: A Procession of Incomes. What Do You Really Mean?     

Sidney Tyrrell 《Teaching Statistics》2003,25(2):59-61

The Family Expenditure Survey provides details of household incomes. This article looks at income distribution afresh and what is meant by the mean.  相似文献   

Ups and Downs on the Roads     

Sidney Tyrrell 《Teaching Statistics》2001,23(1):20-21

  相似文献   

Making it: A principal remembers     

Sidney Trubowitz 《The Urban Review》1972,5(5):10-12

  相似文献