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961.
962.
David B. Hay Caroline Kehoe Marc E. Miquel Stylianos Hatzipanagos Ian M. Kinchin Steve F. Keevil Simon Lygo‐Baker 《British journal of educational technology : journal of the Council for Educational Technology》2008,39(6):1037-1056
This paper shows how concept mapping can be used to measure the quality of e‐learning. Six volunteers (all of them 3rd‐year medical students) took part in a programme of e‐learning designed to teach the principles of magnetic resonance imaging (MRI). Their understanding of MRI was measured before and after the course by the use of concept mapping. The quality of change in individuals' maps was assessed using criteria developed to distinguish between meaningful and rote‐learning outcomes. Student maps were also scored for evidence of conceptual richness and understanding. Finally, each map was compared directly with the content of the electronic teaching material. The results show that many of the student misconceptions were put right in the course of their learning but that many of the key concepts introduced in the teaching were ignored (or sometimes learnt by rote) by the students. This was because the teaching material locked these new ideas in structures and terminology that precluded meaning‐making among non‐experts. Our data suggest that students' prior knowledge is a key determinant of meaningful learning. We suggest that this must be acknowledged if the design and use of electronic teaching material is also to be meaningful. Ultimately, measures of student learning are the only authentic indicators of the quality of teaching through technology. 相似文献
963.
Many adolescents are susceptible to negative outcomes associated with sexual behavior. This is particularly true for those who initiate sexual intercourse at an early age, have many sex partners, or engage in unprotected sex because these behaviors put one at risk for sexually transmitted infections (STIs), including HIV. This article reviews the various demographic, social‐contextual, and intrapersonal factors linked to sexual risk behaviors. Successful STI/HIV prevention programs must consider developmental and gender issues, as well as cultural norms and values, to effectively meet the prevention needs of all adolescents. We discuss the characteristics of effective intervention programs and provide the names and key features of empirically validated, school‐based STI/HIV prevention programs. In addition, we recommend specific roles for school psychologists in STI/HIV prevention efforts. Finally, other resources are provided to assist practitioners in their continuing review of STI/HIV prevention education. © 2007 Wiley Periodicals, Inc. 相似文献
964.
PhD students’ work conditions and study environment in university- and industry-based PhD programmes
During the last 10 years, new models of funding and training PhD students have been established in Denmark in order to integrate industry into the entire PhD education. Several programmes have been conducted where it is possible to co-finance PhD scholarships or to become an employee as an industrial PhD in a company. An important question is what impact these new conditions will have on the PhD students’ training, work conditions and study environment. In this article, the new type of programmes will be presented together with data analysis of PhD students’ work conditions and study environment in various programmes mainly based on a research project from 2006. The results of this study show no significant difference between PhD students in a traditional university PhD programme and PhD students in an industrial programme concerning working environment. However, the study shows significant differences in the intercultural dimension, where foreign PhD students are significantly more satisfied with their study environment compared with Danish PhD students. In general the workload is very high and the environment is stressful for all PhD students. 相似文献
965.
966.
B. M. Deb Mainak Sadhukhan Sudarson Sekhar Sinha Sucheta Sengupta Ranjit Biswas 《Resonance》2008,13(1):54-80
In this article we discuss an exciting experiment in non-linear dynamics. This provides an imaginative platform for bringing
in chemical, physical, biological, mathematical and computational sciences together. There are implications for earth sciences
as well.
B M Deb is a theoretical chemist who has been designing experiments for chemistry teaching laboratories for more than thirty
years.
Mainak Sadhukhan, Sudarson Sekhar Sinha and Sucheta Sengupta were students of PBIR-Chemical Sciences. Ranjit Biswas is a physical
chemist working on both theory and experiment in chemical dynamics. 相似文献
967.
London B 《Sociology of education》1992,65(4):306-316
The analysis of the association between educational status and fertility decline is performed 1) by examining the rates of enrollment in primary and secondary schools by gender and 2) by assessing the effects of the change/spread in rates of enrollment between 1965 and 1986. 59 countries were involved in the cross-sectional analysis. Variables included the logged crude birth rate, total enrollment rates, enrollment rates by gender, male-female ratios, the growth rate for each educational measure by world system status (core, peripheral, and semiperipheral countries), control variables (economic growth, family planning, multinational corporate penetration, women's labor force participation, child mortality rate, social insurance programs), and enrollment changes. The evidence reflects a strong association between levels of enrollment of girls in primary and secondary school and gender inequality and fertility declines. Caldwell's theory of the flows of wealth and the spread of education effect was found to have little support. High levels of female enrollment and low levels of gender inequality in access to schooling are associated with fertility declines. Caldwell's theory is that this indicates a decline in patriarchy, change in women's familial roles and a shift to a more egalitarian family structure. Increases in female education mean higher status and more power for women. 相似文献
968.
969.
For a channel-shoal system in a funnel-shaped basin the impact of dredging and dumping is investigated using a complex process-based
model. First, the residual flow and sediment transport circulations are analysed for the channel-shoal pattern, which has
emerged after a long-term model simulation. Results are compared to the Western Scheldt estuary, which forms the inspiration
for this study. Subsequently, different dredge and dump scenarios are modelled, according to a conceptual model, in which
ebb-and flood-channels and enclosed shoals form morphodynamic units (cells) with their own sediment circulation. Model results
show that dumping sediment in a channel further reduces the channel depth and induces erosion in the opposite channel, which
enhances tilting of the cross-section of the cell and eventually can lead to the degeneration of a multiple channel system
into a single channel. The impact of different dredging and dumping cases agrees with results from a stability analysis. This
means that this type of model applied to a realistic geometry can potentially be used for better prediction of the impact
of human interventions. 相似文献
970.
Many engineering materials demonstrate dynamic enhancement of their compressive strength with the increase of strain-rate, which have been included in material models to improve the reliability of numerical simulations of the material and structural responses under impact and blast loads. The strain-rate effects on the dynamic compressive strength of a range of engineering materials which behave in hydrostatic-stress-sensitive manner were investigated. It is concluded that the dynamic enhancement of the compressive strength of a hydrostatic-stress-sensitive material may include inertia-induced lateral confinement effects, which, as a non-strain-rate factor, may greatly enhance the compressive strength of these materials. Some empirical formulae based on the dynamic stress-strain measurements over-predict the strain-rate effects on the compressive strength of these hydrostatic-stress-sensitive materials, and thus may over-estimate the structural resistance to impact and blast loads, leading to non-conservative design of protective structures. 相似文献