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The Economic of Applying Organic Agriculture for Tomatoes and Potatoes in Riyadh Region
No full textThe main objective of this study is to thoroughly examine the variations between the actual and targeted consumption levels of chemical fertilizers in Saudi agriculture. In addition, an inspection of the impacts of subordinate consumption on the production of tomatoes and potatoes from the economic point of view is achieved. Both partial adjustment models and simulation models are used.
Some of the study results are that: (1) Saudi agriculture depends heavily on the use of nitrate fertilizers. Their share is estimated at 55.4% whereas phosphate and potash shares are estimated at 38.4% and 6.2%, respectively, during the period 1980-2003. (2) During the same period, the actual levels of consuming of total chemical fertilizers have become close to those of the targeted. The actual level is found to be set at 91.5% of the targeted one which is estimated at 395.83 thousand tons.(3) It is anticipated that, under the policy of reducing the consumption of both chemical fertilizers and pesticides with more manure use proportionately, that production, total costs of production, gross, and net returns would decline for tomatoes and potatoes but higher farm prices would be realized due to improvements in the quality of these products.
The study, accordingly, recommends that the environmental aspects should be taken under consideration when developing Saudi agriculture throughout the different Region of Saudi Arabia
THE ECONOMICS OF RATIONING SHEEP CONSUMPTION OF BARLEY AND ITS IMPACT ON BARLEY SUBSIDY IN SAUDI ARABIA
No full textThis study aimed to ration the barley consumption by sheep to control the expanding of barley subsidy. Barley imports reach 6 million tons, and its subsidy reached SR 3240 million in 1995. The traditional sector of animal production consumes 85% of total available barley of which sheep consumes 45.7% it. A linear programming model was used to investigate the possibility of reducing the sheep feed content of barley. Then it was estimated with constraints on both barley and barley with hay.
Results showed that 50% barley sheep feed is the least cost ration, assuming no constraints on barley. In case of imposing constraints on barley, from 80% to 20%, the least cost ration was achieved at barley ratio of 50%, where it costs 0.23 SR/kg. In case of having constraints on both barley and dry hay, the least costs of feed were SR 0.47, 0.35, SR 0.40, and SR 0.47 per kilo for the traditional sector of sheep production, sector of feeding imported sheep, and projects of fattening and breeding sheep, respectively. The ideal contents of a 50 kg feed bag include 25 kg barley 1..2 kg bran, 0.25 kg of lime, and 23.5 kg of wheat straw and costs SR 11.5 per bag.
Barley subsidy for sheep feeding reached SR 2023 million in 1995. Each decrease of barley in sheep feed by 10% results in decreasing the total barley subsidy by SR 274.6 million. So, a 10% decrease in bag content of barley would reduce its subsidy by SR 3. The average per head share of total barley subsidy for sheep reached 71% of its imported value, for the traditional sector
The effect of Soil Fertility on the optimum Fertilizationlevel “An Application on Mexican Wheat and NitrogeninA.R.E.”
No full textThe objective of this study is to estimate the produc¬tion function of Mexican Wheat that reflect accurate rela¬tionship between yield and fertilizer and to be adequate for application in all varieties of soil in A.B.E. The study relied on experimental data. Statistical and eco¬nometric procedures were followed in estimating the rela¬tionship between yield and the utilized quantity of nitro¬gen fertilizer.
The estimated production function was transformed to account for soil fertility and to incorporate both culti¬vated area with Mexican Wheat and nitrogen as explanatory variables. The resulted transformed production function could be used to determine the optimal nitrogen fertili¬zation, to determine the marginal rate of substitution between cultivated area and nitrogen fertilizer, and to provide a successful guidance for the intensification process of production factors
The Structure of Existing and Projected Demand For Imports of Red Meat in the Kingdom of Saudi Arabia
No full textThe objective of this research 1s to study the structure of existing and projected demand for red meat. Demand functions for imports of Important varieties of imported red meat were specified and statistically estimated. The estimated demand models have been utilized in deriving Important Indicators such as elasticities of demand and 1n projecting imported quantities of different varieties of red meat. Income elasticity of demand for imports of various varieties of red meat - Imported as live sheep and goats, Imported as cold and frozen meat of sheep and goats, Imported as live cows, and Imported as cooled and frozen meat of cows - were estimated as 0.586, 0.813, 0.756, 0.624 respectively. An Increase in population •<w1th one thousand would increase the Imports of the mentioned varieties with 34.27, 4.91, 8.65, 13.74 tons respectively. It 1s expected that the relative Importance of sheep and goat meat would increase, while the relative Importance of cow meat would decrease in 1991. It is also expected that live animal would be of more Importance in meat Importing pattern 1n 199
Educational Training Needs For The Teacher Colleges Faculties in Kingdom of Saudi Arabia
No full textThe purpose of this study is to assess the educational training needs of faculties in the Teacher Colleges in Saudi Arabia, and to determine if these training needs differ according to nationality, academic degree, administrative experience, academic rank, study department, and whether the trainee has got any previous training or not.
A questionnaire was administered to a representative sample of 617 faculties. Proper ways of calculating the validity and reliability of the questionnaire were used. Proper ways of statistical analysis, are used to deal with the data of the study.
The results of this study indicate that all skills included in this instrument are considered important training needs from the faculties view point. The mean). Range was between (3.86) and (2.74).
Analysis of variance and Scheffe test revealed significant statistical differences in faculties’ view with regard to the academic degree, study department, administrative experience.
Results concerning the nationality and whether the trainee has got any previous training or not indicate that there were no statistically significant differences in training needs. The results also show that Teachers Colleges are the most accepted organizing educational training program in faculties views. Faculties are found to prefer medium duration programs which are held in the premises and under the auspices of the Teachers Colleges. These are to be held at the beginning of the school years. Visiting professors may supervise workshops and seminars under the auspices of the universities inside the kingdom. Financial as well as psychological incentives are seen to be necessary. Cumulative evaluation is also seen as appropriate means of performance evaluation.
In the light of these results, the researcher gaue some recommendations for the suggested training requirements for college faculties in an attempt to develop their professional capabilities
Minimum fluidization velocities of binary-solid mixtures: Model comparison
No full textAn accurate prediction of the minimum fluidization velocity is a crucial hydrodynamic aspect of the design of fluidized bed reactors. Common approaches for the prediction of the minimum fluidization velocities of binary-solid fluidized beds are first discussed here. The data of our own careful experimental investigation involving a binary-solid pair fluidized with water is presented. The effect of the relative composition of the two solid species comprising the fluidized bed on the bed void fraction at the incipient fluidization condition is reported and its influence on the minimum fluidization velocity is discussed. In this connection, the capability of packing models to predict the bed void fraction is also examined
High density polyethylene / micro calcium carbonate composite: Effect of processing condition on thermal & morphological properties
No full textHDPE with different ratio of CaC03 containing masterbatch were prepared in a Haake batch mixer. The condition of mixing such as mixing temperature and mixing speed were varied in order to mimic the effect of processing condition on the thermal and morphology of the composites. The thermal properties of these composites were evaluated by differential scanning calorimetry (DSC). The crystallization rates of the composites samples are found to be higher than the neat HDPE resin. The presence of CaC03 also affected the melting behavior of the composite by heterogeneous nucleation phenomenon. The dispersion and interfacial interaction between CaC03 and polymer matrix is also investigated by SEM
A compact wideband tunable square ring microstrip antenna
No full textMicrostrip antennas are now extensively used in many applications such as mobile and satellite communications due to their compactness, lightweight, low profile and conformability to any structure. The size of the conventional microstrip antennas such as rectangular, circular, and triangular, patches is large and unsuitable to be used in many applications, especially at the lower microwave range. Various techniques have been investigated in the literature to reduce the size of conventional structures. One can cut slits or slots on the basic shapes which will result in new compact geometries like slotted L-shaped and ring microstrip antennas. The main disadvantage of the resulting compact structures is the associated bandwidth reduction. However, bandwidth can be increased by adding lossy elements in turn of lower antenna efficiencies. One possible solution to avoid the use of lossy elements is the use of tunable or reconfigurable antenna concept [1]. In this case the small size antenna would not cover all bands simultaneously. Instead, it will provide narrower instantaneous bandwidths in a wide tuning range with better antenna efficiencies. © 2010 IEEE.IEE
A novel low SAR PIFA for mobile terminal
No full textThis paper proposes a novel low SAR PIFA structure to reduce exposure of the human head to mobile-set antenna radiation. Dual-band PIFA structures operating at 0.9 GHz and 1.8 GHz bands are considered. SAR is decreased by reducing the back-radiation coming from the patch and the ground plane. This SAR reduction is accomplished by inserting a thin metallic layer between the patch and the ground plane to reduce the current flowing in the ground plane. This layer is connected to the ground plane through few posts located at selected optimum positions. Additionally, three vertical sidewalls are used to reduce radiation from the patch to the human head. Results show that the proposed structure can reduce SAR by up to 76%. ©2010 IEEE.IEE
فعالية برنامج فى الاقتصاد المعرفى فى المستويات المعيارية العالمية لطلاب المرحلة الثانوية التجارية
No full textهذا البحث عبارة عن برنامج مكون من ثمانية وحدات تدريسية تدور حول الاقتصاد المعرفى وأهميته واساليبه وأدواته المختلفة وكيفية تعميق فهم الطلاب لهذا النوع من المعرفة الاقتصادية الجديدة فى ضوء مفهوم مجتمع المعرفة واستخدام تكنولوجيا المعلومات والاتصالات لخدمة الاقتصا