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51.
Weak or non-existent institutions are often cited as a major constraint facing management of many lake basins in Africa. By their nature lake basins cut across many sectoral and jurisdictional interests and therefore it is always the case that management of the basins is affected by actions within the various sectors and jurisdictions. Because of the complex nature of issues within lake basins, authority over management of lake basins is dispersed among several institutions, with no single institution having overall authority. Under these circumstances, a major challenge in lake basin management is how to ensure effective coordination among the various players. This paper reviews the situation of lake basin management at eight African lake basins and draws important lessons about lake basin management institutions. It is noted that fragmented approaches, lack of coordination across sectors, and lack of monitoring and enforcement are major institutional weaknesses. Also, it is observed that political will and commitment are essential for the management of African lake basins.  相似文献   
52.
Successful introduction of pisciculture to reservoirs by the method of migratory fish-farm pasturing is described. __________ Translated from Gidrotekhnicheskoe Stroitel’stvo, No. 9, September 2007, pp. 36–40.  相似文献   
53.
An experienced educationalist comments on the views of top Polish business students on ethics in public life, government and business in modern Poland. The author is Wicklander Professor of Professional Ethics at DePaul University, Chicago, and also served recently as Visiting Fulbright Professor at the Adam Mickiewicz University in Poznan, Poland. He is currently President of the Society of Business Ethics in the USA.  相似文献   
54.
Power Technology and Engineering - Advanced methods for determining the hydrological and geomorphological characteristics of torrential pools, which are important for the design of reliable and...  相似文献   
55.
Power Technology and Engineering - The results of processing annual data of the automated seismometric monitoring system (ASMS) of the Zeya HPP are presented. They are compared with the results of...  相似文献   
56.
Power Technology and Engineering - The paper presents the results of developing a high-speed semiconductor transformer voltage regulator (STVR) intended for a real-time voltage regulation of 0.4 kV...  相似文献   
57.
1.  The use of the results of on-site investigations of an irregular wave load on slopes of structures makes it possible to increase the reliability of designing structures.
2.  A differentiated consideration of the wave load according to probability in storms represented by corresponding quasi-steady wave systems can substantially reduce the cost of construction and installation works on objects of various classes and technical purposes.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 12, pp. 24–27, December, 1989.  相似文献   
58.
1.  Despite their openness, transverse discontinuous structures have a jetty effect.
2.  Discontinuous structures formed by two rows of rectangular support masses connected by longitudinal beams have the strongest effect on the dynamics of a pebble beach.
3.  It can be recommended to use circular supports with a diameter of not more than 2 m arranged in one row at a distance of at least 6 m from one another for constructing hydraulic structures intersecting pebble beaches.
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 5, pp. 23–25, May, 1989.  相似文献   
59.
1.  The side curtains as necessary cutoff elements of the al-Qadisiyah hydro development were made in an optimal design variant, on time, and with a high quality. A considerable technical and economic effect was obtained by eliminating excessive volumes of works specified by the original design as a result of a combined analysis of the data of engineering surveys, investigations of experimental grouting works, and optimization of the grouting technology.
2.  The index of unit cement absorption in the control holes used as the criterion of sufficiency of grouting on the side curtains should be used everywhere where the purpose of grouting works is to detect and eliminate large cavities and fissures.
3.  Grouting works on elimination of karst cavities and large fissures, being in essence infill grouting, require the development of an industrial technology of the works with the use of considerable volumes of grouts (concretes) and use of a large number of machines and mechanisms (concrete plants, mixers, concrete pumps, etc.).
Translated from Gidrotekhnicheskoe Stroitel'stvo, No. 1, pp. 45–50, January, 1989.  相似文献   
60.
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