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562.
A Computer-Aided Learning (CAL) program has been developed as a support aid for students learning the principle of effective stress and its application. The program called ESP (Effective Stress Program) has evolved over a period of two years as a result of research into student learning. This paper discusses the development, use and evaluation of the latest version of the program ESP98. ESP98 is shown to be an effective support tool by outperforming the conventional methods of instruction. The key to the success of ESP98 is the high level of interaction which students experience. The nature of the interaction is centred on a mistake-induced dialogue where the student is provided with progressive and instant feedback and guided towards the final answer. ESP has been integrated into the curriculum at Heriot-Watt University for the past two years and is freely available for use by other teaching institutions by contacting the authors. 相似文献
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Oliver Valins 《Geoforum》2000,31(4)
Institutionalised religion, as a powerful force in the structuring of the daily lives of probably the majority of the world’s population, is a field of social research to which geographers can usefully contribute. This paper examines ancient and contemporary forms of Judaism, exploring the underlying codes and regulations designed to structure every aspect of life. The first part of the paper examines institutionalised uses of space in ancient times, as recorded in the sacred Jewish text of the Talmud. Through the sacred geography of the great Temple in Jerusalem and the legal authority of the religious court to punish offenders, the social system was (in principle at least) highly ordered and regulated. The second part examines the institutionalisation of the religion in contemporary times, which for orthodox Jews involves attempting to practise and maintain these same ancient codes and regulations. Practising ancient ways of life in contemporary (post)modern contexts can be extremely difficult, however, which I discuss with reference to the proposals of the religious authorities in Manchester, England, to construct an eruv; a legalistic device consisting of poles and wires which changes the classification of space, allowing (in particular) the elderly, infirm and parents with young children to travel on the Sabbath. The device faces criticism from secular and religious sources over the rights to ‘claim space’ and the religious legalistic viability of the project. 相似文献
565.
We have analyzed the asymmetry of sunspot areas during the current solar cycle 22, finding that it has been statistically significant and that the shape of the underlying trend within the full asymmetry time series (1874–1993) indicates that the dominance of solar activity has started to shift, during the current cycle, from the northern hemisphere to the southern one. 相似文献
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Sources and geochemical constraints of polycyclic aromatic hydrocarbons (PAHs) in sediments and mussels of two Northern Irish Sea-loughs. 总被引:4,自引:0,他引:4
Polycyclic aromatic hydrocarbons (PAHs) were sampled from 30 sediment and 8 mussel (Mytilus edulis) stations in two Northern Irish Sea-toughs. Analysis was performed by gas chromatography coupled to mass spectrometry (GC-MS). Sedimentary organic carbon, % silt/clay and mean grain size were analysed in order to assess the role of geochemistry on PAH distribution. With the exception of two sites in Larne Lough representing localized regions of high contamination, sum(PAHs) in sediments ranged between 83 and 2300 ng g(-1). Regression analysis indicated that particle size and organic C were dominant factors in controlling the distribution of PAHs throughout the sediments. Sources of PAHs in both sea-loughs were dominated by pyrogenic inputs suggesting that diffuse sources such as atmospheric deposition may be a major source to both water bodies. The sum of PAHs in mussels ranged between 95 and 184 ng g(-1). Variations in concentrations may be explained by differences in the condition between mussel populations. Mussels in both sea-loughs exhibit similar metabolic activities towards the PAH compounds which were predominantly bioaccumulated from sediments. 相似文献
569.
Oliver BM 《The Planetary report》1987,7(6):23-25
On Earth intelligent life evolved as a natural consequence of the events set in motion when the planet formed over 4 billion years ago. Since chemical evolution and solar-system formation appear to be occurring throughout the universe, we theorize that our universe may be rich with planets populated by intelligent beings who, like us, can search for evidence of other technological civilizations. Terrestrial civilization now has this capability. But if we do not begin the search soon, we'll lose the opportunity to do it from Earth as interfering signals of Earthly origin rapidly close the microwave window. 相似文献
570.
Using analytical approximations we study the effects of different external magnetic configurations on the half-width, mass, and internal magnetic structure of a quiescent solar prominence, modelled as a thin vertical sheet of cool plasma. Firstly, we build up a zeroth-order model and analyse the effects produced by a potential coronal field or a constant- force-free field. This model allows us to obtain the half-width and mass of the prominence for different values of the external field, pressure and shear angle. Secondly, the effects of these external magnetic configurations on a two-dimensional model proposed by Ballester and Priest (1987) are studied. The main effects are a change of the half-width with height, an increase of the mass, a decrease of the magnetic field strength with height and a change in the shape of the magnetic field lines. 相似文献