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81.
An experiment designed to train engineering students to two levels of terminal achievement within single institutions is reported. The operative engineers (formerly high level technicians) qualify after three years whilst research and development engineers (fully qualified engineers) take five years. Organisational and curricular problems necessarily created by such integrated schemes are described and discussed. Social attitudes in society in general and in the student body in particular make the task of directing students towards the shorter form of training complex and difficult. From the experience gained so far it can confidently be asserted that the experiments in two-level training have been successful.Note by the Editor: This article is an abbreviated version prepared by the Editor of a 90-page UNESCO (copyright) report with the same title, Document ED. 75/WS/64, dated October 1975. We are grateful to the authors and to UNESCO for permission to print this summary of the report.  相似文献   
82.
Over the last few years, information and communication technologies have become an essential part of daily life, affecting education, employment, and leisure, among other activities. Nonetheless, many individuals still reap few or no benefits from these technologies, and there are resilient gaps in their use. Within this larger context, the authors examine the Internet digital divide between people with and without disabilities from a multidimensional approach. Rather than analyzing the gap in terms of “haves” and “have-nots,” a range of Internet-related dimensions—affordability, motivation and attitudes, skills, usage, and others—is taken into account.  相似文献   
83.
The dynamics of the impact and coalescence of droplets on a solid surface   总被引:1,自引:0,他引:1  
A simple experimental setup to study the impact and coalescence of deposited droplets is described. Droplet impact and coalescence have been investigated by high-speed particle image velocimetry. Velocity fields near the liquid-substrate interface have been observed for the impact and coalescence of 2.4 mm diameter droplets of glycerol∕water striking a flat transparent substrate in air. The experimental arrangement images the internal flow in the droplets from below the substrate with a high-speed camera and continuous laser illumination. Experimental results are in the form of digital images that are processed by particle image velocimetry and image processing algorithms to obtain velocity fields, droplet geometries, and contact line positions. Experimental results are compared with numerical simulations by the lattice Boltzmann method.  相似文献   
84.
Although the importance of intellectual capital has already been highlighted in the management literature, few articles have focused on the importance of its green counterpart, green intellectual capital. Nowadays, when environmental concerns cannot be ignored by firms, it is therefore time to explore the role of green intellectual capital in environmental improvement. For that reason, our research aims to explore the relationships between green intellectual capital components and the environmental performance of the firms. In particular, we try to show the importance of green organizational and social capital in the development of environmental product innovations, which are vital to the development and implementation of environmental strategies since, as scholars have pointed out, they generate some of the greatest environmental impacts. The empirical results show that green organizational capital has an indirect impact on environmental product innovation through green social capital, meaning that the latter is a significant mediator of that relationship, and at the same time emphasizing that informal relationships play a key role in the improvement of the environmental performance of the firm and, more specifically, in the development of environmental product innovations.  相似文献   
85.
In this paper the authors present a preliminary discussion on some of the results from a survey aimed to explore, describe and explain some of the usability characteristics in digital libraries evaluation in the Mexican context. The study is framed in the evaluation of a multinational and monolingual digital library: the Miguel de Cervantes Virtual Library, from the University of Alicante in Spain. The evaluators were Mexican “expert” users (i.e. Spanish-speaking professional university librarians specialized in electronic reference services) who were asked to carry on an evaluation instrument based on usability criteria as taken from some models in developed countries. Some questions that might be answered with future research are outlined in this paper.  相似文献   
86.
The aim of this study was to investigate, for typical shoes and surfaces used in tennis, the relative role of the shoe and surface in providing cushioning during running. Five test surfaces ranging from concrete to artificial turf were selected, together with two shoe models. Impact absorbing ability was assessed mechanically using drop test procedures and biomechanically using peak magnitude and rate of loading of impact force and peak in-shoe pressure data at the lateral heel. Differences in biomechanical variables between shoe-surface combinations were identified using a two-way ANOVA (p < 0.05). Mechanical test results were found to rank the surfaces in the same order regardless of the shoe model, suggesting that the surface is influential in providing cushioning. However, for all mechanical and biomechanical (p < 0.05) variables representing impact absorbing ability, it was found that the difference between shoes was markedly greater than the differences between surfaces. The peak heel pressure data were found to rank the surfaces in the same order as the mechanical tests, while impact force data were not as sensitive to the changes in surface. Correlations between mechanical and biomechanical impact absorption highlighted the importance of testing the shoe-surface combination in mechanical tests, rather than the surface alone. In conclusion, mechanical testing of the shoe-surface combination was found to provide a strong predictor of the impact absorbing ability during running if pressure data were used. In addition, for typical shoe-surface combinations in tennis, the shoe was found to have more potential than the surface to influence impact loading during running. Finally, in-shoe pressure data were found to be more sensitive than force plate data to changes in material cushioning.  相似文献   
87.
88.
This paper describes the application of the methodology developed in research on learning progressions to a health-related topic. More specifically, we present a human nutrition learning progression as a hypothesis that now requires empirical validation. The study involved three phases. In the first phase, we analysed the existing literature in the domain of human nutrition. Based on this analysis, phase 2 then involved drawing up a learning progression for this domain and identifying the learning targets and progress variables, as well as the upper and lower anchors. The analysis led us to identify five progress variables, associated with the development of the concepts of food, nutrient, energy and diet, as well as with the ability to classify foods according to their nutrients. Finally, in phase 3, we identified and described the pathways that students may follow in relation to each progress variable. Given its focus on a topic closely linked to personal health, the learning progression may be useful not only as a component of teaching modules that aim to improve scientific literacy but also as a platform for future health education campaigns that seek to promote healthy eating habits among different sectors of the population.  相似文献   
89.
Recent research in chemistry education has shown an increasing interest in the facilitation of conceptual change in student understanding of chemical concepts. Most of the studies have tried to show the difference in student performance on algorithmic and conceptual problems. The objective of this study is to go beyond and design a teaching strategy based on two teaching experiments that could facilitate students' conceptual understanding of electrochemistry. The study is based on two sections (control, n = 29; experimental, n = 28) of 10th grade high school students at a public school in Venezuela. Experimental group participated in two teaching experiments designed to generate situations/experiences in which students are forced to grapple with alternative responses leading to cognitive conflicts/contradictions. Results obtained show that learning electrochemistry involves both algorithmic and conceptual problems. On Posttest 1, 93% of the experimental group students responded correctly, in contrast to 39% of the control group. On Posttest 2, 39% of the experimental group responded correctly, in contrast to 0% of the Control group. The difference in performance on both posttests is statistically significant (p < 0.001). It is concluded that the teaching experiments facilitated students' understanding (progressive transitions) of electrochemistry.  相似文献   
90.
The objective of this study was to describe the anthropometric profiles of elite older triathletes participating in the 2009 Ironman Brazil and to compare their somatotype, anthropometric and body composition characteristics with those of elite young triathletes and older non-athletes. The sample consisted of 64 males, divided into three groups: (1) older triathletes (n = 17), (2) young triathletes (n = 24), and (3) older non-athletes (n = 23). Somatotype was analysed according to the Carter and Heath ( 1990 ) method. Body mass index, sum of four skinfolds, percentage body fat, body fat mass, and fat-free mass were also estimated. Older non-athletes had higher endomorphy, sum of four skinfolds, fat percentage, and body fat mass than the athletes. Older athletes who participated in the Ironman and elite young triathletes had higher fat-free mass than older non-athletes. Older triathletes and older non-athletes were considered mainly endomorphic mesomorphs and young triathletes mainly ectomorphic mesomorphs. The findings that characterize the anthropometric profile of athletes in this sports modality could be used as a reference.  相似文献   
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