In this study, several models of the rocket fins were made of hyper composite materials (with two or more reinforced materials) with different volume fractions of components used to produce isotropic composite plate structures. The reinforcement of polyester resin material was done in two ways, with fibre reinforcement and powder reinforcement. The types of fibresthat used were chopped glass fibre and chopped carbon fibre, and the type of powder used was carbon powder. A concentrated load was applied to the models in the form of a cantilever plate. The effect of adding carbon powder on the stiffness to weight ratio and the effect of temperature on this stiffness to weight ratio were studied and discussed. It was observed that hybridization improves the properties of composite materials at certainspecific volume fractions of carbon powder. The best percentage of improvement of the value of stiffness was69.87% in a specimenmade of 50% polyester, 30% glass fibres, and 20% carbon powderin terms of models reinforced with glass fibres, while for models reinforced with carbon fibres, it was 79.94% in the model made of 60% polyester, 30% carbon fibre, and 10% carbon powder. In addition, the results showed that an increase in temperature leads to a decrease in the stiffness to weight ratio for all models. The smallest effect of temperature on the stiffness to weight ratio was shown in the sample composed of 50% polyester, 30% glass fibres, and 20% carbon powder, at 45.83% for the models reinforced with chopped glass fibres, and in the model made of 60% polyester, 20% carbon fibres, and 20% carbon powder at 57.54% for models reinforced with carbon fibres.
The article presents the results of studying the conchological variability of the terrestrial mollusk Chondrulopsina fedtschenkoi (Ancey, 1886), known to occur in three regions of the Zaravshan Range (Central Asia): the Urgutsay Gorge, the vicinity of the Gissarak Reservoir and the Ingichka-Irmak Gorge. Conchological variability was determined based on statistical analysis. The climate of the three regions is different, and environmental factors have led to changes in the mollusk shell. The shells have changed in response to environmental factors, these are their adaptive traits for survival; the variability of conchological features is also reflected in the color of the shell, and the intensive development of the color of the shell in m
... Show MoreA particle swarm optimization algorithm and neural network like self-tuning PID controller for CSTR system is presented. The scheme of the discrete-time PID control structure is based on neural network and tuned the parameters of the PID controller by using a particle swarm optimization PSO technique as a simple and fast training algorithm. The proposed method has advantage that it is not necessary to use a combined structure of identification and decision because it used PSO. Simulation results show the effectiveness of the proposed adaptive PID neural control algorithm in terms of minimum tracking error and smoothness control signal obtained for non-linear dynamical CSTR system.
Background/purpose: Dental implantology involves different treatments that have been used in conjunction with dental implant surgery to increase implant stability and bone regeneration process. Photobiomodulation( PBM) can be one of these techniques. The objective of this study was to evaluate the bone density around implants. Materials and methods: in this study, 10 individuals had 20 implants inserted in the posterior of their mandibles. each patient received two implants the left side served as the control whereas the right side served as the study group with a diode laser (same patients). measurements were made for each implant. Measurements were obtained using cone-
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Objective: To assess pregnant women Knowledge toward Urinary Tract Infection at Kirkuk City.
Methodology: A descriptive and analytical study was conducted from 1st of November 2013 and up to the 19 th of August 2014 in five typical primary health care centers at Kirkuk City. A Probability (randomly sample) was used to select the sample of 180 women aged (15-44) years. A questionnaire format was used as a tool for data collection , content validity of the questionnaire achieved through reviewing it by (24) experts in numerous scientific fields and reliability of the questionnaire was determined through a pilot study. Descriptive and inferential statistics were used to analyze the data.
Resul
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This research deals with studying and analysis of a poetic group under the
title (Trees behind fence) of the great poet Dr. Ahmed Sulaiman AlAhmed
who is the some of the Shek , Sulaiman Al-Ahmed who is the linguist - poet
and famous jurist member in the Arabic scientific assemble in Damascus and
brother of the great poet Badawi Al-Jabal. This poetic group include two big
poetic legends : the first one is (Trees behind fence , ) which include one
hundred and eighty four line and the second one ( AZ-Mebadia ) which is
consists of one hundred and seventy eight line, both of them from the (Al-
Camil ) meter which is free rhyme which bears a many meaning and pictures
and just the great poet composite the
During the educational practices in the Spanish department at the Faculty of Languages , University of Baghdad , we noticed that the personal pronouns in effect replaced by the direct and indirect characterized hardly be expressed , and the difficulty of her education.
Rationale: I chose this topic because the personal pronouns differ between the Spanish language and the Arabic language. We believe that this study may be useful not only for language teachers, but also for students, because it can contribute to a greater awareness of and correct weaknesses.
Objectives: To apply the model from which to address the problems in the use of personal pronouns Spanish , and the difference between effect of direct and indire
... Show MoreBackground: Beta-thalassemia major is the most common monogenic known disorder in the Middle East, characterized by anomalies in the synthesis of the beta chains of hemoglobin resulting in variable phenotypes ranging from severe anemia to clinically asymptomatic Individuals. This study aimed to evaluate salivary flow rate and salivary IgA in β-thalassemia major patients. Since many oral and systemic conditions manifest themselves as changes in the flow and composition of saliva the dental practitioner is advised to remain up-to-date with this issue. Materials and methods: The study samples consist of (60) subjects, patients group composed of (30) patients with β –thalassemia major, age rang (5-23) years and (30) healthy locking
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The aim of the research is to verify the role of organizational trust as an “administrative” dimension of objective importance in the relationships adopted by the Iraqi General Insurance Company with customers, as it is one of the basic pillars in building and succeeding companies, which allows the provision of services with high confidence through the customer relationship management system in order to achieve The company's goal is to gain new customers, retain current customers, increase work in insurance companies, and develop the national economy by increasing the company's sales and profitability. The research
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