An experimental study was conducted to determine the performance of a solar electric refrigeration system. The system contained flat photovoltaic solar panel which absorbs the solar energy and convert it to electrical energy, used to run the refrigeration cycle. Two refrigeration cycles with electrical solar panel were used over a period of 12 months, the first one with classical parts known in refrigeration cycle, while the second one introduced heat exchanger which improves the coefficient of performance by saving the consumed energy. The coefficient of performance of these refrigeration cycles with compressor efficiency 85% are 2.102 and 2.57 respectively. The overall efficiency of the two systems are 18.9% and 23.13%.
In this research, the mechanism of cracks propagation for epoxy/ chopped carbon fibers composites have been investigated .Carbon fibers (5%, 10%, 15%, and 20%) by weight were used to reinforce epoxy resin. Bending test was carried out to evaluate the flexural strength in order to explain the mechanism of cracks propagation. It was found that, the flexural strength will increase with increasing the percentage weight for carbon fibers. At low stresses, the cracks will state at the lower surface for the specimen. Increasing the stresses will accelerate the speed of cracks until fracture accorded .The path of cracks is changed according to the distributions of carbon fibers
Arabic calligraphy is one of the greatest achievements of Islamic art. The visual form of Arabic calligraphy is the primary means of presenting ideas and messages for expressive communication in Arabic typefaces. Emerging computer technology with calligraphy is essential for effective visual designs; however, traditional typefaces are insufficient in number and quality to fulfill the requirements of the current Saudi industry. Thus, this research investigates the processes followed by graphic designers to create modern Arabic type designs inspired by Arabic calligraphy, and presents the characteristics of Arabic calligraphy. The research implemented a mixed experimental and descriptive method, exploring 10 typefaces designed by professio
... Show MoreA computational investigation is carried out in the field of charged –particle optics with the aid of numerical analysis method using the personal computer. The work is concerned with the design of electron gun with space-charge effect. The Finite element method (FEM) used in the solution of Poison's equation for determine the axial potential distribution of the two-electrode immersion lens operated under zero magnification condition , and from the solution of the paraxial ray equation the optical properties such as the focal length , spherical and chromatic aberration coefficients are determined, also a calculation of the brightness and perveance for the lens. The electrodes geometry was determined in two and three dimensi
... Show MoreThe development of the television industry has led to the emergence of a new type of entertainment program in which producers have abandoned stereotypes in traditional programs, known as (Reality TV show). This type of program has spread rapidly in America, (where there are more than 40 series of these programs), as well as Europe and more than twenty countries around the world, including the Arab countries, where the number of these programs today to about 1000 programs and the number is increasing , Especially with the readiness of the production networks to produce more of these programs for the huge profits they derive from them (because of the high viewing rates and the large number of ads broadcast through them) in return for low prod
... Show MorePolynomial IIR digital filters play a crucial role in the process of image data compression. The main purpose of designing polynomial IIR digital filters of the integer parameters space and introduce efficient filters to compress image data using a singular value decomposition algorithm. The proposed work is designed to break down the complex topic into bite-sized pieces of image data compression through the lens of compression image data using Infinite Impulse Response Filters. The frequency response of the filters is measured using a real signal with an automated panoramic measuring system developed in the virtual instrument environment. The analysis of the output signal showed that there are no limit cycles with a maximum radius
... Show MoreThe objective of this work was to analyze the involvement of AhR in bone metabolism using a rat model of experimental osteoporosis and to analyze the mechanisms behind its activity. Rats were assigned randomly to the subsequent groups; Control, received no treatment; ovariectomized (OVX) rats; Sham; Sham+RES received resveratrol; OVX+RES and OVX+CH received AhR’s antagonist, CH223191 (CH); and finally OVX+CHR group received both AhR antagonist along with resveratrol. Resveratrol and AhR antagonist treatment started 7 days after surgery and continued to 45 days. The serum of osteocalcin (OC) and Ca+2 was measured by ELISA and spectrophotometer, respectively. X-ray was used to estimate bone density of rats. In molecular levels,
... Show MoreThe media guide is a small-sized printed medium, whose importance is highlighted through the specific information it carriesThe task of the guide lies in the clarity of these indications and making a positive impact on the recipient with understanding so it is a means for the purpose of reaching the effect and effectiveness of the message symbols from the movements of lines in which elements that are supposed to be equal in the performance of their functions and the purpose of their existence gather to achieve the mental response of perception, understanding and enjoyment. It must be in an objective unity based on the balance in this distribution. To form a formal organizational unit and an integrated system, the result of which is to gi
... Show MoreThis paper deals with two preys and stage-structured predator model with anti-predator behavior. Sufficient conditions that ensure the appearance of local and Hopf bifurcation of the system have been achieved, and it’s observed that near the free predator, the free second prey and the free first prey equilibrium points there are transcritical or pitchfork and no saddle node. While near the coexistence equilibrium point there is transcritical, pitchfork and saddle node bifurcation. For the Hopf bifurcation near the coexistence equilibrium point have been studied. Further, numerical analysis has been used to validate the main results.
Background: Chronic suppurative otitis media (CSOM) is the result of aninitial episode of acute otitis media and is characterized by a persistent discharge from the middle ear through a tympanic perforation for at least 2 weeks duration. It is an important cause of preventable hearing loss, particularly in the developing world.Methods. 1. To get an overview on the bacterial ear infection profile in general 2. To assess the antibiotic resistance of Pseudomonal infection (PS) particularly since it is usually the commonest infection to cause otitis media and the most difficult to treat due to the problem of multi drug resistance... A cross sectional study was done which included 405 patient of CSOM patients196 (48%) case were males ,209 (52
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