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In the first half of this century a computing problem became evident in the course of preparatory research for major hydraulic projects in the Netherlands. One of the most novel problems was to predict the changes in the tidal movements caused by hydraulic works in coastal waters. Between 1920 and 1960 several solutions were proposed and put into practice: numerical methods, contracting young men for the calculations, analogue electronical networks and large scale models. The amount of computing labour played a decisive part in the choice between these methods. After a storm surge in 1953 causing estensive inundations in the southern part of The Netherlands, the requirements of the Delta Works project gave an enormous impetus to all three types of methods. 相似文献
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Fons De Zeeuw 《Development and change》1997,28(3):583-595
Lack of formal security of land tenure is often cited as a constraint for participatory land management programmes which try to motivate African farmers to grow trees and to realize other improvements in their fields in order to control soil erosion. According to this approach, the borrowing of land would represent an insecure form of land tenure hindering sustainable land use. However, on the basis of a case study in Burkina Faso, this article demonstrates that this is not necessarily so: borrowing arrangements may play a part in avoiding local overload of the carrying capacity and in an efficient distribution of village lands among the farming units. Furthermore, borrowing does not hinder some major intensification techniques of land use which are currently being applied in Burkina Faso. Legal interventions which aim to increase security of tenure and to create favourable conditions for sustainable land use may in fact have the opposite effect. 相似文献
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J. W. De Jong 《Indo-Iranian Journal》1975,16(3):161-182
Sans résumé
A propos de Amalia Pezzali, {Śāntideva, mystique bouddhiste des VIIe et VIIIe siècles}, Firenze, Vallecchi Editore, 1968.
USA $7.80. 相似文献
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George Cardona Henry L. Danielson G. Chemparathy J. W. De Jong 《Indo-Iranian Journal》1975,17(1-2):103-120