Circular thin walled structures have wide range of applications. This type of structure is generally exposed to different types of loads, but one of the most important types is a buckling. In this work, the phenomena of buckling was studied by using finite element analysis. The circular thin walled structure in this study is constructed from; cylindrical thin shell strengthen by longitudinal stringers, subjected to pure bending in one plane. In addition, Taguchi method was used to identify the optimum combination set of parameters for enhancement of the critical buckling load value, as well as to investigate the most effective parameter. The parameters that have been analyzed were; cylinder shell thickness, shape of stiffeners section and the number of stiffeners. Furthermore, to verify the contribution of parameters on buckling response, the analysis of variance technique (ANOVA) method was implemented, which gave the contribution weight as percentages. The analysis of results by these two methods showed that the more effective parameter on the critical buckling load was the thickness of cylinder’s shell and the lowest effective was the number of stiffeners The values of parameters that gave the best critical buckling load combination were: 1) the ratio of cylinder’s diameter to thickness of its shell was 133, 2) the ratio of the depth to thickness of stiffeners was1.6, and 3) the number of stiffeners was 12.
Unlike fault diagnosis approaches based on the direct analysis of current and voltage signals, this paper proposes a diagnosis of induction motor faults through monitoring the variations in motor's parameters when it is subjected to an open circuit or short circuit faults. These parameters include stator and rotor resistances, self-inductances, and mutual inductance. The genetic algorithm and the trust-region method are used for the estimation process. Simulation results confirm the efficiency of both the genetic algorithm and the trust-region method in estimating the motor parameters; however, better performance in terms of estimation time is obtained when the trust-region method is adopted. The results also show the po
... Show MoreThe 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
... Show MoreObjectives: To explore the correlation between maternal and cord blood prolactin, the correlation between cord prolactin and birth weight, and to compare cord blood prolactin in new-borns of women with normal pregnancy and women with pregnancy complications namely; gestational hypertension, gestational diabetes and preterm labour.Methods: This study was performed from September to December 2018. Thirty-two women, delivered at Baghdad teaching hospital, and their newborns (32) were included. Maternal blood (5 ml) was taken before labour and cord blood (5 ml) was collected after placenta expulsion. Maternal and cord blood prolactin were analysed using fluorescence immunoassay. Results: Cord blood prolactin was higher in babies b
... Show MoreBackground: This study aims to determine whether cigarette smoking and anxiety degrees are related among nurses. Methods: A correlation design study was conducted at Baquba Teaching Hospital in Diyala Governorate, and the study period extended from September 10th, 2023, to January 28th, 2024. A nonprobability purposive sample was used to include 200 nurses working at Baquba Teaching Hospital, Iraq. Data were collected using a self-administered questionnaire from January 10th to February 7th, 2024. There were two components to the study instruments. Initially, the demographic sheet contained the individuals' sociodemographic data. The Taylor manifest anxiety scale is included in the second section. The collected data were analyzed us
... Show MoreThe possible effect of the collective motion in heavy nuclei has been investigated in the framework of Nilson model. This effect has been searched realistically by calculating the level density, which plays a significant role in the description of the reaction cross sections in the statistical nuclear theory. The nuclear level density parameter for some deformed radioisotopes of (even- even) target nuclei (Dy, W and Os) is calculated, by taking into consideration the collective motion for excitation modes for the observed nuclear spectra near the neutron binding energy. The method employed in the present work assumes equidistant spacing of the collective coupled state bands of the considered isotopes. The present calculated results for f
... Show MoreThe aim of the research is to assess the practice of tax administration to diminish the strategic direction of (proactive, analytical, defensive, response) and the nature of its relationship to organizational excellence represented by (leadership, strategic planning, focus on taxpayers, information and analysis and knowledge management, focus on operations, focus on forces. The questionnaire was adopted as a main tool in collecting data and information from the sample members of the General Authority for Taxes (110) who are in the site (m. Second Division Manager, Ms The statistical program (SPSS) was used to calculate (mean, standard deviation, difference coefficient, correlation coefficient, t-test). The research reached a number
... Show MoreIn this work, the effect of atomic ratio on structural and optical properties of SnO2/In2O3 thin films prepared by pulsed laser deposition technique under vacuum and annealed at 573K in air has been studied. Atomic ratios from 0 to 100% have been used. X-ray diffraction analysis has been utilized to study the effect of atomic ratios on the phase change using XRD analyzer and the crystalline size and the lattice strain using Williamson-Hall relationship. It has been found that the ratio of 50% has the lowest crystallite size, which corresponds to the highest strain in the lattice. The energy gap has increased as the atomic ratio of indium oxide increased.
The importance of the research lies in preparing exercises using a proposed device to learn the skill of thehuman wheel on a machine rug of ground movements of the artistic gymnastics. As for the research problem:Through the presence of the two researchers as teachers and observers of this sport in the gymnastics hall,they noticed that there is difficulty in the students’ performance of the skill of the round off on the machineof the mat of ground movements, according to the researchers’ opinion, the reason for this is that skillsare taught with the limited availability of assistive devices, as well as the lack of use of these devices inexercises according to biomechanical variables, although they facilitate the learning process
... Show MoreIndustrial development has recently increased, including that of plastic industries. Since plastic has a very long analytical life, it will cause environmental pollution, so studies have resorted to reusing recycled waste plastic (sustainable plastic) to produce environmentally friendly concrete (green concrete). In this research, producing environmentally friendly load-bearing concrete masonry units (blocks) was considered where five concrete mixtures were compressed at the blocks producing machine. The cement content reduced from 400 kg/m3 (B-400) to 300 kg/m3 (B-300) then to 200 kg/m3 (B-200). While (B-380) was produced using 380 kg/m3 cement and 20 kg/m3 nano-sil
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