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61.
M. M. El Bakry 《Theoretical and Applied Climatology》1994,49(3):129-133
Summary Net radiation is an essential parameter for estimating evaporation from large water surfaces by energy balance method. Net radiation has been measured for the first time over the Aswan High Dam Lake on the Nile River for 132 days including warm and cold seasons. A high multiple linear correlation coefficient of 0.98 was obtained between the measured net radiation on the one hand and the global solar radiation measured at Aswan and the difference between water and air temperatures measured over the Lake on the other hand.Seven different empirical formulae for estimating the effective outgoing radiation have been applied on the average data measured over the Lake for days of clear sky. It has been found that the Swinbank formula is the best one suitable for the location of the Aswan High Dam Lake.With 2 Figures 相似文献
62.
R. O. Greiling M. M. Abdeen A. A. Dardir H. El Akhal M. F. El Ramly G. M. El Din Kamal A. F. Osman A. A. Rashwan A. H. N. Rice M. F. Sadek 《International Journal of Earth Sciences》1994,83(3):484-501
Detailed structural geological and related studies were carried out in a number of critical areas in the Proterozoic basement of eastern Egypt to resolve the structural pattern at a regional scale and to assess the general characteristics of tectonic evolution, orogeny and terrane boundaries. Following a brief account of the tectonostratigraphy and timing of the orogenic evolution, the major structural characteristics of the critical areas are presented. Collisional deformation of the terranes ended about 615-600 Ma ago. Subsequent extensional collapse probably occurred within a relatively narrow time span of about 20 Ma (575 – 595 Ma ago) over the Eastern Desert and was followed by a further period of about 50 Ma of late to post-tectonic activity. The regional structures originated mainly during post-collisional events, starting with those related to extensional collapse (molasse basin formation, normal faulting, generation of metamorphic core complexes). Subsequent NNW-SSE shortening is documented by large-scale thrusting (towards the NNW) and folding, distributed over the Eastern Desert, although with variable intensity. Thrusts are overprinted by transpression, which was localized to particular shear zones. Early transpression produced, for example, the Allaqi shear zone and final transpression is documented in the Najd and Wadi Kharit-Wadi Hodein zones. Two terrane boundaries can be defined, the Allaqi and South Hafafit Sutures, which are apparently linked by the high angle sinistral strike-slip Wadi Kharit-Wadi Hodein shear zone with a tectonic transport of about 300 km towards the W/NW. In general, the tectonic evolution shows that extensional collapse is not necessarily the final stage of orogeny, but may be followed by further compressional and transpressional tectonism. The late Pan-African high angle faults were reactivated during Red Sea tectonics both as Riedel shears and normal faults, where they were oriented favourably with respect to the actual stress regime. 相似文献
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65.
To resist seismic overturning moments piles are often designed for tensile forces which require pile connection to the cap and sometimes, socketing. For typical buildings, this paper theoretically examines the effect of these measures on seismic response, forces and pile loading in dependence on pile numbers, configuration and tip conditions. 相似文献
66.
The study focuses on the analysis of manufacturing industry in Saudi Arabia by examining development, structure and spatial distribution. The analysis has shown that Saudi manufacturing is basically of recent development and is highly capital- and energy-intensive, particularly the hydrocarbon-based groups. Perhaps the most conspicuous weakness of Saudi industrialization is the almost total dependence on expatriate labour. Foreign capital and expertise share in the building and development of the industrial sector by providing technical, managerial, and marketing skills. Saudi industry is heavily subsidized by the government, and the public sector plays a commanding role in industrial development. Large-scale basic industries are owned and run by the government, while light manufacturing of the import-substitution type is dominated by the private sector. One of the main characteristics of manufacturing industry is that it is scantily diversified, modestly concentrated and remarkably linked geographically but not functionally or structurally. Although the authorities are exerting tremendous efforts to achieve a regional balance in industrial development, Saudi manufacturing industry is significantly polarized, urban-oriented and highly associated with the major axes of population scatter. Like all developing countries beginning to industrialize, Saudi manufacturing industry faces certain problems which have to be resolved so as to lay the foundations for a sound and prosperous industrial future. The paper goes on to indicate problems and to suggest solutions. 相似文献
67.
Community perception and participation,prospects in management of forests in marginal lands of Sudan
Fuelwood Development for Energy in Sudan project (GCP/SUD/033/NET) is undertaking research to formulate management plans for Sudan ecologically marginal forests. Rawashda and Wad Kabu forests are taken as examples to initiate sound plans. It is believed that the study of socio-economic parameters of forests users is an essential component to achieve such plan. This study is also fundamental for attaining an integrated land use system, as a prime option of natural resource use. This study is, consequently, aiming at:
- Providing the base line information of the different communities identified in Tab 3 and using the two forests.
- Examine people's attitude, perception, participation options in maintenance and management of the two forests. Such parameters are also vital for adoption of an integrated land use strategy in the future.
- Based on (i) and (ii) to outline broadly the most relevant plan of management land use strategy to be adopted, based on community self-generated options of institutions and objectives of use.
- A complex pattern of economic activities (Tab 3) ranging from pure pastoral nomadism to modern mechanized farming, still characterized by combination of related activities of agricultural/livestock breeding, agriculture/forest resource use, etc. This diversity in activities, which is mostly dependent on the natural resource base, gives a sound base for any option of an integrated land use system.
- Perception and attitude analysis have revealed a growing awareness of the role of the forest resources in the economy as source of grazing, domestic needs and source of income. This awareness is supported by willingness to participate in any integrated land use plan, yet from a different stand point and objective. Preference of self-generated channels is quite evident, but with a specified role of the government.
- The major finding is that, and among all communities, the situation is mature for action, although at different levels.
68.
M A Mohammed Aslam A Balasubramanian 《Journal of the Indian Society of Remote Sensing》2001,29(4):237-242
Visual interpretation of satellite images could help in the identification of present and past landforms. An attempt has been made to identify the palaeochannels of the Cauvery river in Karnataka state through visual interpretation of IRS-1C, LISS III False Colour Composites (FCC). In order to assess their inter-relationship with other hydrogeomorphic elements, various geomorphic units have been mapped. Major geomorphic units like alluvial plain, pediplain, valley fill. residual hill, ridges, meander scar, channel bars and water bodies have been demarcated. Considering the hydrogeomorphic setup of the palaeochannels. it is inferred that the disposition of palaeochannels of the area are controlled by the geology and structure and the prevailing geomorphic process. 相似文献
69.
Mohammed Ilyas Arunsala Pandy Mohd. Suhaimi Jaafar 《Journal of Atmospheric Chemistry》2001,40(2):111-121
The South-East Asian region experienced a haze episode in 1994 which was widely believed to be due to widespread forest fires in Sumatra and Kalimantan (Indonesia). Broadband measurements of the surface level solar ultraviolet-B, UV-A and Global radiation at Penang (Malaysia) are used to study the effect of the 1994 haze on effective UV-B irradiance. We find that during the haze episode, there is enhanced absorption of surface level UV-B radiation. The effect of haze on UV-A and Global radiation is much less. The reduction in absolute noon time UV-B irradiance (mostly cloud free) during the 1994 haze period was 23% relative to the UV-B irradiance during thecorresponding haze-free period in 1995. Even though the noon time radiation data minimizes the cloud effect in the results presented some cloud effect is still present. 相似文献
70.
S. M. El shazly 《大气科学进展》1996,13(3):349-358
The performance of two models,Jam and Baig,based on the modified version of Gaussian distribution function in estimating the daily total of global solar radiation and its distribution through the hours of the day from sunrise to sunset al any clear day is evaluated with our own measured data in the period from June 1992 to May 1993 in Qena Egypt The results show a high relative deviation of calculated values from measured ones,especially for Jain model,in the most hours of the day,except for those near to local noon.This misfit behavior is quite obvious in the early morning and late afternoon A new approach has been proposed in this paper to estimate the daily and hourly global solar radiation This model performs with very high accuracy on the recorded data in our region.The validity of this approach was verified with new measurements in some clear days in June and August 1994.The resultant very low relative deviation of the calculated values of global solar radiation from the measured ones confirms the 相似文献