The main objective of this research is to design and select a composite plate to be used in fabricating wing skins of light unman air vehicle (UAV). The mechanical properties, weight and cost are the basis criteria of this selection. The fiber volume fraction, fillers and type of fiber with three levels for each were considered to optimize the composite plate selection. Finite element method was used to investigate the stress distribution on the wing at cruise flight condition in addition to estimate the maximum stress. An experiments plan has been designed to get the data on the basis of Taguchi technique. The most effective parameters at the process to be find out by employing L9 (33) orthogonal array, signal to noise ratio (S/N), main effect and analysis of variance (ANOVA). The results show that, the experimental and the predicted results are very close. It was found that the type of fiber is the most effective parameter on the plate selection, followed by filler content and then the fiber volume fraction. The best parameters combinations are ((E-glass woven roving + unidirectional carbon) fiber, 7.5% graphite filler and 30% fiber volume fraction). This combination provides good mechanical properties, high safety factor, acceptable cost, and offers weight savings on average by 40% percent as compared to aluminum alloy.
Thin-walled members are increasingly used in structural applications, especially in light structures like in constructions and aircraft structures because of their high strength-to-weight ratio. Perforations are often made on these structures for reducing weight and to facilitate the services and maintenance works like in aircraft wing ribs. This type of structures suffers from buckling phenomena due to its dimensions, and this suffering increases with the presence of holes in it. This study investigated experimentally and numerically the buckling behavior of aluminum alloy 6061-O thin-walled lipped channel beam with specific holes subjected to compression load. A nonlinear finite elements analysis was used to obtain the
... Show MoreThe inhibitory behavior of L-Cysteine (Cys) and its derivatives towards iron corrosion through density functional theory (DFT) was investigated. The current research study undertakes a rigorous evaluation of global as well as local reactivity descriptors of the Cys in protonated as well as neutral forms and the changes in reactivity after the combination of Cys into di- and tripeptides. The inhibitory effect of di- and tri-peptides increases since, in the molecular structure, the number of reaction centers increase. We computed the adsorption energies (Eads) and low energy complexes with most stability for the adsorption of small peptides and Cys amino acids onto the surfaces of Fe (1 1 1). We found that the adsorption of tri-peptides onto
... Show MoreIn the present work, experimental tests was done to explain the effect of insulation and water level on the yield output. Linear basin, single slope solar still used to do this purpose. The test was done from May to August 2017 in Mosul City-Iraq (Latitude: Longitude: Elevation: 200 m, and South-East face). Experimental results showed that the yield output of the still increased by 20.785% and 19.864% in case of using thermal insulation at 4cm and 5cm respectively, also the yield output decrease by 15.134% as the water level increase from 4 to 5cm, with the presence of insulation and 14.147% without it. It has been conclude that the insulation and water level play important role in the process of passive
... Show MoreObjective(s): The aim of this study was to assess the severity of anemia among children under 5 years and to find
out relationship between severity of anemia in children with socio-demographic variables such as: child gender,
age, supplement diet, hookworm, pica, parent's education level, father's and mother's occupation, and family
monthly income with severity of anemia
Methodology: A descriptive cross sectional study was conducted at the primary health care centers in Alsadr city
for the period of 1
st July 2011 to the 1st November 2011.Non probability (purposive) sample of (630) children who
aged under 5 years and who attended to primary health care centers of Alsadr city. The data were collected
through using
Abstract
The current research sought to demonstrate the effect of material flow cost accounting on reducing products through the application of material flow cost accounting technique, which works on the optimal utilization of materials and energy and the reduction of environmental impacts.The research aims to clarify the knowledge foundations for material flow cost accounting, in addition to studying the material flow cost accounting technique that helps reduce the cost of products and make them environmentally friendly. To achieve this, the research relied on the descriptive approach with regard to the theoretical aspect of the resea
... Show MoreThrough the title of the research, it is clear that beliefs in different religions are considered the important principles that distinguish religions, sects, and sects from each other, and belief is the important foundation and pillar on which the individual and society is based, because God Almighty called for reflection and reflection to choose his peaceful belief away from blind imitation. It is (belief in the existence of God, and His unification - and glorifying His attributes - and belief in the prophets in general, and belief in the angels in general, and in the revealed books in general).
The Islamic thought still suffers from the problems posed by Western thought in the modern era, especially after the establishment of the modern Arab state, and replacing the intellectual reference that prevailed at that time, which is represented by Islamic thought with another intellectual reference represented by Western thought. Since then, thinkers and innovators and reformers and intellectuals of the Islamists, Are trying to get out of these many problems and multiple, after imposing the nature of that thought and those references with all their consequences, and one of these problems that is still Islamic thought suffers, the bilateral problem that some academics have raisedThe title of the symposium failed The Islamic thought and
... Show MoreModern linguistic theories have given the researchers some real opportunities to find out important linguistic phenomena that
تعد فرقة المعتزلة من الفرق الإسلامية الكبيرة التي شغلت حيزاً كبيراً في التاريخ الإسلامي, فقد ظهرت المعتزلة كفرقة ذات نسق عقيدي مميز الى الوجود في العصر الأموي , ولكنها شغلت الفكر الإسلامي في العصر العباسي عندما بلغت أوج قوتها ردحاً طويلاً من الزمن .
Al-Jahiz was an aesthetic philosopher, and the concept of beauty for Al-Jahiz depended on objectivity and focus on the idea of moderation