Experiment was conducted in Baghdad, three factor were used in this research included Two types of Plows included moldboard and disk plows which represented the main plot, Three forward speeds of the tillage was the second factor included 1.85, 3.75 and 5.62 km / h which represented sup plot , and Three levels of Soil Moisture was third factor included 21, 18 and 14 % in all of Vertical and Lateral Plowing Deviation, Practical and specific productivity, actual time for plowing one donam and appearance (goodness) of Tillage represented by the number of clods > 10 cm in silt clay loam soil with depth 22 cm were studied. the experiment was used Split – split plot design under randomized complete block design with three replications and Least Significant Design 5 % was used to compare the means of treatments . Mold-board plow recorded the best Practical and specific productivity for plowing which was 1.247 donam/ hr and 2379 m / hr, and lower actual time for plowing one donam 0.972 hr and Appearance Tillage number of clods > 10 cm was 9.555 clods/m2 , Disc Plow recorded the least Vertical and Lateral Deviation for Plowing which was 2.325% and 2.357% . Tillage Speed 5.62 km/hr recorded higher Practical and specific productivity 1.672 donam/hr and 3452 m/hr respectively and lower actual time 0.608 hr and number of clods > 10 cm was 8.166 clods/m2, Speed 1.85 km/hr recorded lower Vertical and Lateral Deviation Plowing 1.221% and 1.068% respectively. Soil Moisture 18 % recorded higher Practical and specific productivity 1.168 donam /hr and 2400 m /hr respectively, lower actual time 1.047 hr and lower number of clods > 10 cm was 9.500 clods/m2. Soil Moisture 21% recorded lower Vertical and Lateral Deviation for Plowing 1.978% and 1.901% respectively. All Interactions among treatments had significant effect on the parameters studded under this experiment.
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In this paper an attempt to provide a single degree of freedom lumped model for fluid structure interaction (FSI) dynamical analysis will be presented. The model can be used to clarify some important concept in the FSI dynamics such as the added mass, added stiffness, added damping, wave coupling ,influence mass coefficient and critical fluid depth . The numerical results of the model show that the natural frequency decrease with the increasing of many parameters related to the structure and the fluid .It is found that the interaction phenomena can become weak or strong depending on the depth of the containing fluid .The damped and un damped free response are plotted in time domain and phase plane for different model parameters It is fou
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Many numerical approaches have been suggested to solve nonlinear problems. In this paper, we suggest a new two-step iterative method for solving nonlinear equations. This iterative method has cubic convergence. Several numerical examples to illustrate the efficiency of this method by Comparison with other similar methods is given.
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In this paper, a computational method for solving optimal problem is presented, using indirect method (spectral methodtechnique) which is based on Boubaker polynomial. By this method the state and the adjoint variables are approximated by Boubaker polynomial with unknown coefficients, thus an optimal control problem is transformed to algebraic equations which can be solved easily, and then the numerical value of the performance index is obtained. Also the operational matrices of differentiation and integration have been deduced for the same polynomial to help solving the problems easier. A numerical example was given to show the applicability and efficiency of the method. Some characteristics of this polynomial which can be used for solvin
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