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alkej-452
The Effect of Wind Velocity on the Suppression of Composite Wing Airfoil NACA 0012
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The first studies on shocks and vibrations were carried out at the beginning of the 1930s to improve the behavior of buildings during earthquakes. Vibration tests on aircraft were developed from 1940 to verify the resistance of parts and equipments prior to their first use. Flutter is a well-known example of dynamic aero elasticity, where when oscillation of structure interacted with unsteady aerodynamic forces the flutter will occur. Vibration on any structure without damping means that self-harmonic oscillation will occur, and in most cases the oscillation may start to increase until structural failure. This behavior is very similar to resonance phenomena if only the oscillation is being studied as a vibration case. In vibration suppression, the active vibration control is one of the more effective technique which is used for attenuating bad effects of disturbances on structure. In this work, two different composite wings have been used; one of them is made of Glass-fiber random matt and the other is made of woven ({0/90} Glass-fiber). The proportional-integral-derivative (PID) control is employed here for studying the suppression of active vibration wing affected by wind velocity flow through wind tunnel in the laboratory of mechanical engineering department at the university of Baghdad. Piezoelectric (PZT (transducers are used as sensors and actuators in vibration control systems. The attack angle was 10 degrees and three different velocities (15, 20, 35 m/s) have been taken to show their effect on the wings vibrations suppression. Is noticed that the suppression of the wing amplitude is reduced when the wind velocity increases for both woven and random composite wing matt. This is happened due to the vortex which has became more violent increase in wind velocity. It is concluded that the composite woven wing has high resistance more than the composite random wing. Also, the maximum control amplitude of woven matt is 1.9 cm and the damping is about 33% at 25 m/s wind velocity while the amplitude is 2.22 cm and the damping is about 53% at 10 m/s wind velocity for random wing.

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Publication Date
Mon Sep 30 2024
Journal Name
Joiv : International Journal On Informatics Visualization
Evaluation of the Performance of Kernel Non-parametric Regression and Ordinary Least Squares Regression
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Researchers need to understand the differences between parametric and nonparametric regression models and how they work with available information about the relationship between response and explanatory variables and the distribution of random errors. This paper proposes a new nonparametric regression function for the kernel and employs it with the Nadaraya-Watson kernel estimator method and the Gaussian kernel function. The proposed kernel function (AMS) is then compared to the Gaussian kernel and the traditional parametric method, the ordinary least squares method (OLS). The objective of this study is to examine the effectiveness of nonparametric regression and identify the best-performing model when employing the Nadaraya-Watson

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Publication Date
Mon Jan 01 2024
Journal Name
Aip Conference Proceedings
The dynamical behavior of AIDS and HCV infection model with two modes of transmission
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The aim of this paper is to describe an epidemic model when two SI-Type of diseases are transmitted vertically as well as horizontally through one population. The population contains two subclasses: susceptible and infectious, while the infectious are divided into three subgroups: Those infected by AIDS disease, HCV disease, and by both diseases. A nonlinear mathematical model for AIDS and HCV diseases is Suggested and analyzed. Both local and global stability for each feasible equilibrium point are determined theoretically by using the stability theory of differential equations, Routh-Hurwitz and Gershgorin theorem. Moreover, the numerical simulation was carried out on the model parameters in order to determine their impact on the disease

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Publication Date
Thu Dec 26 2019
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
ANATOMICAL STUDY OF SOME SPECIES BELONGING TO THE PAPAVERACEAE FAMILY IN NORTH OF IRAQ
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    The anatomical features of leaves and stems of seven species belonging to five genera of the Papaveraceae family were studied, including: Fumaria bracteosa Pomel, 1875; Glaucium grandiflorum Boissier & A. Huet,1856; Hypecoum pendulum Linnaeus, 1753; Papaver fugax Poiret,1804; Papaver macrostomum Boissier & A. Huet, 1867; Papaver rhoeas Linnaeus, 1753 and Roemeria refracta de Candolle,1821. The results showed that the anticlinal cell walls of the adaxial surface were more thickened in P. fugax, H. pendulum, P. macrostomum and R.refracta, while it was thin in P. rhoeas. The cur

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Publication Date
Sat Sep 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Role of Tourism Industry in the Developing of Economie to Iraq for (1990- 2009)
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The Developing economies of countries have witnessed essential changes to words the development of tourism industry in the 21st century . in addition to adopting same of policies and strategies to grow up with the tourism sector to make it one of the important economic sector to compete the tourist cal  developments in the wear .

As for the tourism sector in Iraq ,it's still afresh one , has many of elements which can be in vested ,needs a wide strategies of tourist cal in statutes and variety completive services and change of success for the locale and forgin investor ,the essential aim after this research is to prompt the national economic through the tourism industry and making concisen

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Publication Date
Tue Jul 01 2025
Journal Name
Minerva Dental And Oral Science
Evaluation of the microleakage of new bioactive restorative materials: a comparative in-vitro study
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Publication Date
Sun Apr 07 2013
Journal Name
Journal Of Educational And Psychological Researches
The Sources of psychological Stress with students living at dormitories in university of Baghdad.
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Stress with all its kinds are the results of a nick development Leading to delinquency burdening the ability of people.. development gas its effect on self and body reflecting on health ( physically, Psychological. And mentally) and finally leading to death (Al emara,2001,2).

Stress refers to he degree of response of the individual to events and environmental changes in his daily life with their physiological effects  such as headaches , backaches, and gastric ulcer that have different effect depending on the personality of the person and his psychological characteristics differences airing individuals ( Al emirs, zool,2  )

The aims:

  • knowi

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Publication Date
Sun Nov 27 2022
Journal Name
Al–bahith Al–a'alami
Gender stereotyping and its relationship to the level of performance of public relations employees
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This article focuses on the relationship of gender to the effectiveness of both women and men in public relations work. Its aim is to identify the extent to which public relations employees are aware of the concept of gender, and to reveal the role of the institution in determining certain roles for both women and men at work, as well as to find out which employees are most effective in public relations activities within the institution.

The researcher uses public relations employees and officials in Iraqi ministries as a research sample to capture the point of view of both parties on the effectiveness of workers in public relations based on the definition of gender. The sample consists of 396 individuals

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Publication Date
Wed Aug 26 2020
Journal Name
Iraqi Journal Of Agricultural Sciences
COMPARISON THE ACCURACY OF COMPUTING POINT COORDINATS BETWEEN DIFFERENT INSTRUMENTS AND APPLICATIONS OF GPS
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The study was aimed to determine the coordinates of  the points were measured by different ways and different instruments, the most precise way using the differential global positioning system (DGPS) that will be the reference measurements in comparison, less precise way using navigator GPS. Google earth (pro.), and the other applications of GPS mobile ( Samsung and I-phone). In this research (8 points) were chosen that are occasional in location. The comparison of the different observations can give us an idea of ​​the extent to which the accuracy of the observations differs from the different devices used in the observing, as well as through the knowledge of the best device and the best way to measure coordinates accurately t

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Publication Date
Fri Mar 01 2013
Journal Name
Advances In Bioresearch
Comparative Evaluation of Alkaloids Extraction Methods from the Root Bark of Punica granatum Linn
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A comparative study was carried out to evaluate alkaloid antibacterial activity which was extracted from the root bark Punica granatum L. by liquid membrane techniques (SA) and organic solvent traditional techniques (SB). The screening of the antimicrobial activity was conducted by agar well diffusion method against Staphylococcus aureus, Enterobacter cloacae, Escherichia coli, Klebsiella pneumoniae, and Proteus mirabilis at three concentration levels (5, 10 and 15 mg/ml). Alkaloid extracts were analyzed by a high performance liquid chromatography (HPLC) method. Among the tested extractions, SB showed the highest antibacterial activity against all five bacterial strains, especially at 15 mg/ml concentration. However, all the B type solution

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Publication Date
Wed Feb 22 2012
Journal Name
مجلة تكريت للعلوم الصرفة
Study the activity of ALT and AST in serum of diabetic patients type II
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