الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
River Nile and ground water are the main sources of water supply in Egypt. Agriculture consumes the bulk of the available water supply. There is a compelling necessity for Egypt to continue its programme of land reclamation; to meet the food quantity and quality expectations of the expanding population. Therefore, it is necessary to optimize the use of the available national water resources to save water for these new lands and upgrowing water needs. A considerable effort is being made by the scientific organizations in Egypt to reduce the water losses at the field level. These efforts are concerned with the using of efficient methods of irrigation that discharge water close to the plant where it will be consumed.
Pressurized systems of irrigation are well-known methods and widely used to satisfy crop water requirements with minimum wastage. The widely used pressurized methods to irrigate agricultural lands are sprinkle and trickle irrigations. It is necessary to know what must be done to select from the many candidates the ‘best type and configuration’ of irrigation system for each specific site situation. There is not a blueprint for the design process, but all the available in literature are suggestions. The cost of the system is important factor that must be considered during the selection and design of the system.
The main goal of this research is to develop a computer model to select the set of most promising, adaptable system types and configurations that may satisfy the field and design criteria. The model consists of main program and subroutines. The model is written using visual basic language as it is a practical language. The model gives output on AutoCAD file with full details. The selection procedure focus on economic and institutional, as well as physical parameter associated with different system types and configuration. The design technique used herein gives the minimum sum of capital and operation costs. After completing the layout and design, a full economic analysis for each system is made to make comparisons and final selection. This economic analysis is completed on an annualized cost basis.
The study reveals that, field dimensions ratio (L/B) should be in the range 1.00 to 1.67 to obtain minimum operating cost and use alignments Ss x Sl (9x12, 9x15, 12x12 and 12x15) and avoid using alignment (9x18 and 12x18). Field dimension Ratio gives minimum cost at (L/B) =2.0. For minimum cost in solid set sprinkler irrigation and line source trickle irrigation systems the most suitable field area about 60 feddan. In which the field area is more than this, field should be divided to achieve minimum cost.