The aerodynamic characteristics of the forward swept wing aircraft have been studied theoretically and an experimentally investigation for the wake field generated by this configuration have been carried out. Low order panel method with the Dirichlet boundary condition have been used to solve the case of the steady, inviscid and compressible flow. Two different panel method techniques have been employed: the source-doublet and the doublet method. The thickness for the various components was considered in the study. Prandtl-Glauert similarity rule has been used to account for the compressibility effects. Experimentally, a model was manufactured from wood with body length (290mm) and main wing span was (204mm). The primary objective of the experimental work was the measurements of the wake dimensions and orientation, velocity distribution along the wake and the wake thickness and growth. The experiments were conducted to four different configurations at four angles of attack. A blower type low speed wind tunnel with solid walls was used in the experimental work. The mean velocity at the test section was (9.3 m/s) and the Reynolds number based on the mean aerodynamic chord was (0.46x105). The measurements showed the existence of a three-dimensionality behavior in the wake flow field. Interference between the canard wake and the wing wake was observed. The canard effect on the wing root area was detected as the separation at the wing root was delayed due to the canard downwash. The velocity defect and wake thickness are increased with the increase of the angle of attack. The comparison of the numerical results with the other published data showed that the method is capable of predicting the aerodynamic coefficients for complex configurations with reasonable accuracy. The source-double method was more accurate and faster than the doublet method for the same number of panels. The aerodynamic coefficients for the forward swept wing aircraft was calculated using the real wake shape measured in the experimental work. Numerical results showed that the canard extended the range of the angle of attack for the aircraft with a significant improvement for the lift curve slope compared to the aircraft without the canard.
English has for long been one of the most widely used media of communication globally, especially in the Malaysian universities. It has been termed as a Lingua Franca because it is shared with other languages which are considered first languages by different speakers. For this reason, English as a Lingua Franca (ELF) has attracted a number of researchers to investigate its variety via other languages in various communities. The objective of this paper is therefore to establish the strategies which are employing by the international students at the National University of Malaysia/ UniversitiKebangsaan Malaysia (UKM) as an example of one of the Malaysian universities; when they e
... Show MorePurpose: The present study seeks to examine various history stages in which undergone by the concept of scenarios, and development of this concept to integration with the strategic management practices:
Methodology: The current study relied on a literature review and approach in providing total picture of different stages undergone by this concept.
The main results: the scenarios did not reach maturity in their quest for integration with strategic management, and still need a great effort for the maturation of this thought in the framework of strategic management, and through it can contribute in creating important knowledge evolution.
Originality and value: providing a contemporary model linking the roots of this concept and cu
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This study reports the fabrication of tin oxide (SnO2) thin films using pulsed laser deposition (PLD). The effect of 60Co (300, 900, and 1200 Gy) gamma radiation on the structural, morphological, and optical features is systematically demonstrated using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM), and ultraviolet-visible light analysis (UV-Vis), respectively In XRD tests, the size of the crystallites decreased from 45.5 to 40.8 nm for the control samples and from 1200 Gy to 60Co for the irradiated samples. Using FESEM analysis, the particle diameter revealed a similar trend to that attained using XRD; in particular, the average diameters were 93.8 and
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Abstract
This study was to demonstrate the role-use planning scientific methods is disabled and little used in the planning and follow-up construction of vital projects in the province of Baghdad, including network planning methods, in order to find the optimal time to finish the project in light of the resources available and the budget set for it, in the current research has been used the most prominent network planning methods and two stylistic (CPM / PERT), was the application of the critical path method on standard-design school project (traditional) to draw Action Network according to confirmed times for the activities of the project and account his Crashing time , It was Pert technique applied to the project hemato
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The research aims to determine the strength of the relationship between time management and work pressure and administrative leadership, where he was taken a sample of (47) of the administrative leadership at the Higher Institute of security and administrative development in the Ministry of Interior was used questionnaire as a key tool in collecting data and information and analyzed the answers to the sample surveyed by using Statistical program (spss) in the arithmetic mean of the calculation and test (t) and the correlation coefficient, the research found the most important results: the existence of significant moral positive relationship between both time management and work pressure and administrative leadership, the leadership of th
... Show MoreThis study was conducted to examine the anatomical aspects of
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The influence of silver doped n-type polycrystalline CdTe film with thickness of 200 nm and rate deposition of 0.3 nm.s -1 prepared under high vacuum using thermal co-evaporation technique on its some structural and electrical properties was reported. The X- ray analysis showed that all samples are polycrystalline and have the cubic zinc blend structure with preferential orientation in the [111] direction. Films doping with impurity percentages (2, 3, and 4) %Ag lead to a significant increase in the carrier concentration, so it is found to change from 23.493 108 cm -3 to 59.297 108 cm -3 for pure and doped CdTe thin films with 4%Ag respectively. But films doping with impurity percentages above lead to a significant decrease in the electrica
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