Abstract

Theoretical and experimental methodologies were assessed to test curved beam made of layered   composite material. The maximum stress and maximum deflection were computed for each layer and the effect of radius of curvature and curve shape on them. Because of the increase of the use of composite materials in aircraft structures and the renewed interest in these types of problems, the presented theoretical assessment was made using three different approaches: curved beam theory and an approximate 2D strength of material equations and finite element method (FEM) analysis by ANSYS 14.5 program for twelve cases of multi-layered cylindrical shell panel differs in fibe

The behavior of externally prestressed composite beams under short term loading has been studied. A computer program developed originally by Oukaili to evaluate curvature is modified to evaluate the deflection of prestressed composite beam under flexural load. The analysis model based on the deformation compatibility of entire structure that allows to determine the full history of strain and stress distribution along cross section depth, deflection and stress increment in the external tendons .
The evaluation of curvatures for the composite beam involves iterations for computing the strains vectors at each node at any loading stage. The stress increment determined using equations depended on the member deflection at points of connecti

The present work divided into two parts, first the experimental side which included the
measuring of the first natural frequency for the notched and unnotched cantilever composite beams
which consisted of four symmetrical layers and made of Kevlar- epoxy reinforced. A numerical
study covers the effect of notches on the natural frequencies of the same specimen used in the
experimental part. The mathematical model for the beam contains two open edges on the upper
surface. The effect of the location of cracks relative to the restricted end, depth of cracks, volume
fraction of fibers and orientation of the fiber on the natural frequencies are explored. The results
were calculated using the known engineering program (ANSY

The relationship between chronic hepatitis B virus and Helicobacter pylori infection was evaluated to determine, seventy five patients with chronic hepatitis B infection (8-70 years) were investigated. The results were compared with the results of 50 healthy volunteers. Anti-H. pylori antibodies IgA and IgG were measured by Indirect fluorescent antibody test (IFAT) in sera of patients and healthy groups. The percentage of anti-H.pylori IgA antibodies (26.67%) were significantly (P<0.01) higher than healthy control group. While, no significant difference was found between the percentages of anti-H. pylori IgG antibodies (48 %) in patient sera and these kind of antibodies in sera of healthy control group (P > 0.05). The present results indica

This study accomplished to determine levels of salivary Alpha-Amylase (sAA) in Iraqi children with positive family history of hypertension, Hypertension was believed to be a risk factor in 18% of all deaths in 2010 (9.4 million globally). This study included one hundred children from primary school aged 6 to 13 years, with a focus in child welfare and family health history, with an emphasis on close relatives' hypertension reputations, with hypertension close relatives record categories identified by 1st and 2nd relatives, after documenting the full details, the burden was assessed for the children's families. The influence of age is confirmed by a correlation study of our own numbers, which shows a positive correlation. The disparity betwe

Rheumatoid arthritis is an inflammatory chronic disease with an autoimmune pathogenesis. To determine the role of Helicobacter pylori as a trigger agent, twenty five patients with rheumatoid arthritis of ages (15-47) years have been investigated and compared with twenty healthy individuals. All the studied groups were carried out to measure the rheumatoid arthritis (RA) IgM, anti-CCP antibody IgG and IgA by ELISA test and by measured anti-IgG antibody level of H. pylori by using ELISA and IFAT techniques. The present study showed significant differences (P< 0.05) of anti-H. Pylori in sera of RA patients than control group, this lead to suggest that H. pylori had a role in pathogenesis of RA.

This paper studies the influence of temperature on the corrosion rate of coated AA6111 aluminum alloy used in vehicle bodies under static and vibration states. The vibration test system was collected laboratory and used for testing of five different types of paints (EASI, Numix, Lesonal, DENSO and Polaron paints) in the 5 % NaCl solution using immersion test method. Lesonal paint provided the best corrosion protection, while DENSO paints show large values of corrosion rate, other coatings exhibit moderate values. Model of paints corrosion was developed to characterize the corrosion processes occur at the surfaces. It is found that corrosion rate obtained at vibration cases is larger than static cases and vibration effect

In this work, we are obviously interested in a general solution for the calculation of the image of a single bar in partially coherent illumination. The solution is based on the theory of Hopkins for the formation of images in optical instruments in which it was shown that for all practical cases, the illumination of the object may be considered as due to a self – luminous source placed at the exit pupil of the condenser , and the diffraction integral describing the intensity distribution in the image of a single bar – as an object with half – width (U0 = 8 ) and circular aperture geometry is viewed , which by suitable choice of the coherence parameters (S=0.25,1.0.4.0) can be fitted to the observed distribution in various types of mi