الفهرس 
IntroductionOnly 14 pages are availabe for public view
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Abstract
The crops that planted on the ridged soil facing an obstacle because most available cultivators are appropriate for the crops that planted on the leveled soil surface (flat soil) only, besides the fact that these cultivators are too large and too expensive for small fields. Furthermore, weed control in the crops that planted on the ridges mainly done manually or chemically. Thus, the development of a combined machine for hoeing the crop planted on the flat and the ridged soils and reforming the ridges is the main objective of this study. The performance of the developed machine was evaluated to determine the effect of different parameters, i.e., two different cultivation depths (0-20 mm and 0-40 mm), two different shapes of the rotary blades (C-shaped blade and L-shaped blade), five different kinematic indices (5.85, 6.76, 7.54, 8.32 and 8.84) and two different methods of crop planting (planting in the flat soil and planting in the ridged soil) on weeding efficiency, plant damage percentage, soil penetration resistance, field capacity and efficiency, fuel consumption, engine power, specific energy, shape of row profile and cost estimation. The results revealed that, the optimum operation parameters for both the flat and the ridged soils during the two cultivations were using the L-shaped blade at cultivation depth of 40 mm and kinematic index of 7.54. In addition, adjusting the tilt angle of the flanges to be 32±0.50◦ and 29±0.42◦ during the first and the second cultivations, respectively. The hourly operating costs of the developed cultivator was 14.42 LE/h as a separate unit. The maximum total costs for two cultivations in the flat and the ridged soil were 588.70 and 626.15 LE/fed, respectively, compared with the hand cultivation which recorded 980 LE/fed for two cultivations.