The reduction of vibration properties for composite material (woven roving E-glass fiber plies in thermosetting polyester matrix) is investigated at the prediction time under varied combined temperatures (60 to -15) using three types of boundary conditions like (CFCF, CCCF, and CFCC). The vibration properties are the amplitude, natural frequency, dynamic elastic moduli (young modulus in x, y directions and shear modulus in 1, 2 plane) and damping factor. The natural frequency of a system is a function of its elastic properties, dimensions, and mass. The woven roving glass fiber has been especially engineered for polymer reinforcement; but the unsaturated thermosetting polyester is widely used, offering a good balance of vibration properties at moderate or ambient temperatures, and also at relatively low cost. The mismatch between matrix and fiber yarns gives a predominant role for the fiber's mechanics where the matrix is the area where most damage mechanisms develop. The free vibration test was carried out for (5, 10, 15, 20, 25, 30) minutes. The composite plate was exposed to (75) of thermal gradient for ten times in various times at different stages. The results were classified into experimental and finite element using software ANSYS Ver. 9.
Experienced economic environmentRadical changes at the end of the last century and the beginning of the present century, resulting in new concepts and expectations in all aspects of economic, political, social and even behavioral.Each of these concepts is the result of rapid developments in the intangible space. Competition is no longer limited to the mere possession of tangible material resources, but because of its link to knowledge and technology content and to the comprehensive quality standards and efficient and effective policies of States. With the increasing pace of growth and interdependence among the global economies, this resulted in the birth of a new economic system led by technological development and financial liberalizati
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This study was conducted in the poultry field of the department of animal production, college of agricultural engineering sciences, university of Baghdad for the period from 10/15/2021 to 11/25/2021 with the aim of showing the effect of adding different levels of dill seeds to the diet on productive and carcass traits For broiler meat. In this study, 200 unsexed broiler chicks of breed (Ross 308) were used, one day age, with a starting weight of 41.46 g. The chicks were randomly distributed to 5 treatments, and each treatment included 4 replicates, 10 birds for each replicate. The birds were fed three diets: the starter diet, the growth diet and the final diet. The experiment treatments were T1,
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Background: There is a strong desire of adolescent to have a peer group and to be appreciated and also to become a member of this group which can affect one each other. There for; encourage, adapting,and imitating of friends and group consider as the main reasons behind starting of smoking among youngsters. Smoking habits in the family were found tobe acause of smoking pressure among adolescentas peer pressure. Smoking habit may be started before 18 years of age in most adult smokers.
Objectives: To study the effect of peer pressure and family smoking habiton the prevalence of smoking among secondary school students.
Type of the study: A cross
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This study aims to find out the effectiveness of instructional scaffolding strategy in the development of academic achievement and critical thinking of female second grade secondary mathematics students. Semi-experimental and relational descriptive method was used. The sample of the study consisted of (50) students divided into an experimental group and a control group. The experimental group was taught using scaffolding strategy whereas the control group was taught using traditional method. Pre- and Post-tests were used to achieve the objective of the study. The results of the study revealed that there are statistically significant differences in the mean scores of the experimental and control groups in the posttest for both the academi
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Maulticollinearity is a problem that always occurs when two or more predictor variables are correlated with each other. consist of the breach of one basic assumptions of the ordinary least squares method with biased estimates results, There are several methods which are proposed to handle this problem including the method To address a problem and method To address a problem , In this research a comparisons are employed between the biased method and unbiased method with Bayesian using Gamma distribution method addition to Ordinary Least Square metho
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يتضمن ھذا البحث تحضير وتشخيص بعض المعقدات الفلزية التي تحوي على ليكاندات مختلطة ل (Amoxicillin)( Axn (و(Picoline-٣) (Pic-٣ (وقد تم دراسة ھذه المعقدات بالطرائق الطيفية (اIشعة تحت الحمراء و اIشعة المرئية –فوق البنفسجية والتوصيلية الموIرية والحساسية المغناطيسية ، ومن نتائج ھذه الدراسات التشخيصية امكن اعطاء الصيغة المقترحة العامة لھذه المعقدات و كاIتي
This work, deals with Kumaraswamy distribution. Kumaraswamy (1976, 1978) showed well known probability distribution functions such as the normal, beta and log-normal but in (1980) Kumaraswamy developed a more general probability density function for double bounded random processes, which is known as Kumaraswamy’s distribution. Classical maximum likelihood and Bayes methods estimator are used to estimate the unknown shape parameter (b). Reliability function are obtained using symmetric loss functions by using three types of informative priors two single priors and one double prior. In addition, a comparison is made for the performance of these estimators with respect to the numerical solution which are found using expansion method. The
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The stage of the establishment of the Alawite state in tabaristan was one of the most important stages in the history of the Shiite sect in Iran
The stage of the establishment of the Alawite state in tabaristan was one of the most important stages in the history of the Shiite sect in Iran , from a political , religious and even military point of view ,