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Many researchers have stressed that the acoustic environment is crucial to the speech perception, academic performance, attention, and participation of students in classrooms. Classrooms in highly urbanised locations are especially vulnerable to noise, a major influence on the acoustic environment. The purpose of this investigation was to determine noise levels in one such urban environment, Hong Kong. The ambient noise level, and its relationship to the speech intensity levels of both teachers and students was surveyed in 47 primary school classrooms. Moreover, the presence of acoustical treatments for noise reduction and the use of classroom amplification systems were documented for each classroom. The survey found that the mean occupied noise level was 60.74 dB (A); the mean unamplified and amplified speech‐to‐noise ratios of teachers were 13.53 dB and 18.45 dB, respectively; while the mean unamplified speech‐to‐noise ratio for students was 4.13 dB. Most of the classrooms exhibited insufficient acoustical treatments to provide significant noise reduction. The listening environment in many Hong Kong primary schools was not favourable for optimal classroom learning. Recommendations for improving the acoustical environment in classrooms in highly urbanised locations such as Hong Kong are discussed.  相似文献   
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Two levels of training (100 vs. 500 trials) and two ages of rats (young and adult) were used in a developmental analysis of the relationship between response strength and the effects of punishment. The apparatus was a Y maze with three discriminably different arms. After 100 or 500 reinforced trials, subjects were shocked each time they responded in one arm. The recovery sessions followed the punishment session. Results from the punishment day indicated that: (a) young rats received a greater amount of shock, and (b) additional training increased the amount of shock received by the young but decreased it in the adults. The recovery data showed that: (a) the suppressive effects of punishment were greater for the adults than for the young, and (b) the recovery scores were not influenced by degree of overtraining. The Age by Overtraining interaction suggested that the relationship between response strength and punishment is age dependent. The age differences found with the amount-of-shock and recovery measures provided additional support for the position that younger rats are less competent than adult rats in inhibiting responses.

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The present study examined the role of verbal working memory (memory span and tongue-twister), two-character Chinese pseudoword reading (two tasks), rapid automatized naming (RAN) (letters and numbers), and phonological segmentation (deletion of rimes and onsets) in inferential text comprehension in Chinese in 31 less competent comprehenders compared with 37 reading comprehension control students and 23 chronological age controls. It was hypothesized that the target students would perform poorly on these cognitive and linguistic tasks as compared with their controls. Furthermore, verbal working memory and pseudoword reading would explain a considerable amount of individual variation in Chinese text comprehension. RAN would have a nonsignificant role in text comprehension. Structural equation analyses and hierarchical multiple regression analyses generally upheld these hypotheses. Our findings support current literature of the role of verbal working memory in reading comprehension found in English. The results, however, suggest differential role of the constructs and the tasks in reading comprehension and provide some answers for comprehension impairment in Chinese students.  相似文献   
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This article seeks to understand the ways in which feedback was communicated in post-observation conferences in teaching practice supervision within the learning-oriented field experience assessment (LOFEA) framework. 32 post-observation conferences between 21 pairs of supervisors and participants of in-service teacher education programmes, and interviews with supervisors and participants were analyzed, with findings revealed in four themes:
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The distribution of content and nature of feedback in post-observation conferences;  相似文献   
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We present a new approach to enhance mixing in T-type micromixers by introducing a constriction in the microchannel under periodic electro-osmotic flow. Two sinusoidal ac electric fields with 180° phase difference and similar dc bias are applied at the two inlets. The out of phase ac electric field induces oscillation of fluid interface at the junction of the two inlet channels and the constriction. Due to the constriction introduced at the junction, fluids from these two inlets form alternative plugs at the constricted channel. These plugs of fluids radiate downstream from the constriction into the large channel and form alternate thin crescent-shaped layers of fluids. These crescent-shaped layers of fluids increase tremendously the contact surface area between the two streams of fluid and thus enhance significantly the mixing efficiency. Experimental results and mixing mechanism analysis show that amplitude and frequency of the ac electric field and the length of the constriction govern the mixing efficiency.  相似文献   
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Electroosmotic flow (EOF) with two or more fluids is commonly encountered in various microfluidics applications. However, no investigation has hitherto been conducted to investigate the hysteretic or flow direction-dependent behavior during the displacement flow of solutions with dissimilar ionic species. In this investigation, electroosmotic displacement flow involving dissimilar ionic solutions was studied experimentally through a current monitoring method and numerically through finite element simulations. The flow hysteresis can be characterized by the turning and displacement times; turning time refers to the abrupt gradient change of current-time curve while displacement time is the time for one solution to completely displace the other solution. Both experimental and simulation results illustrate that the turning and displacement times for a particular solution pair can be directional-dependent, indicating that the flow conditions in the microchannel are not the same in the two different flow directions. The mechanics of EOF hysteresis was elucidated through the theoretical model which includes the ionic mobility of each species, a major governing parameter. Two distinct mechanics have been identified as the causes for the EOF hysteresis involving dissimilar ionic solutions: the widening/sharpening effect of interfacial region between the two solutions and the difference in ion concentration distributions (and thus average zeta potentials) in different flow directions. The outcome of this investigation contributes to the fundamental understanding of flow behavior in microfluidic systems involving solution pair with dissimilar ionic species.  相似文献   
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This paper examines how the role of patents and utility models in innovation and economic growth varies by level of economic development. Using a panel dataset of over 70 countries, we find that patent protection is an important determinant of innovation and that patentable innovations contribute to economic growth in developed countries, but not in developing. Instead, in developing economies, a minor form of intellectual property rights (IPRs) - namely utility models - is conducive to innovation and growth, controlling for other factors. Using Korean firm level data as a case study, we find that utility model innovations contribute to firm performance when firms are technologically lagging and that those minor innovations can be a learning device and thus a stepping stone for developing more patentable inventions later on. Upon reaching higher levels of technological capabilities, firms become more reliant upon patents and less on utility models. Thus the lesson here is that patent protection enhances innovation and economic growth in countries where the capacity to conduct innovative research exists. Where this capacity is weaker, a system that provides incentives to conduct minor, incremental inventions is more conducive to growth. The significance of this paper is to emphasize the importance not just of the strength of IPRs but of the appropriate type of IPRs for economic development.  相似文献   
10.
Partnership evaluation typically occurs during the final stages either to assess why a collaborative effort did not work or to identify the indicators of success. Partnerships are rarely evaluated at their incipient stage, which is a critical time to assess their potential for long-term sustainability. In this paper, we present an early-stage evaluative framework for assessing multi-institutional academic partnerships’ sustainability based on 3 dimensions: decision processes, problem orientation, and social capital. We apply the evaluative framework using case study research to the Renewable Energy Assessment (REA) Program, a workforce enhancement academic partnership that focuses on facilities and lands viability assessment. Using the evaluative framework, we identified critical elements present within and missing from the REA Program that could influence the partnership's long-term sustainability. This study demonstrates the need to conduct incipient stage and ongoing evaluations to foster partnership sustainability, and provides a framework for conducting such assessments.  相似文献   
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