The aerodynamic characteristics of general three-dimensional rectangular wings are considered using non-linear interaction between two-dimensional viscous-inviscid panel method and vortex ring method. The potential flow of a two-dimensional airfoil by the pioneering Hess & Smith method was used with viscous laminar, transition and turbulent boundary layer to solve flow about complex configuration of airfoils including stalling effect. Viterna method was used to extend the aerodynamic characteristics of the specified airfoil to high angles of attacks. A modified vortex ring method was used to find the circulation values along span wise direction of the wing and then interacted with sectional circulation obtained by Kutta-Joukowsky theorem of the airfoil. The method is simple and based mainly on iterative procedure to find the wings post stall aerodynamic results. Parametric investigation was considered to give the best performance and results for the rectangular wings. Wing of NACA 0012 cross sectional airfoil was studied and compared with published experimental data for different speeds and angle of attacks. Pressure, skin friction, lift, drag, and pitching moment coefficients are presented and compared good with experimental data. The present method shows simple, quick and accurate results for rectangular wings of different cross-section airfoils.
Data steganography is a technique used to hide data, secret message, within another data, cover carrier. It is considered as a part of information security. Audio steganography is a type of data steganography, where the secret message is hidden in audio carrier. This paper proposes an efficient audio steganography method that uses LSB technique. The proposed method enhances steganography performance by exploiting all carrier samples and balancing between hiding capacity and distortion ratio. It suggests an adaptive number of hiding bits for each audio sample depending on the secret message size, the cover carrier size, and the signal to noise ratio (SNR). Comparison results show that the proposed method outperforms state of the art methods
... Show MoreThe performance of the pavement in terms of vehicle safety and tire wear is affected by the friction behavior of the pavement. To highlight the main characteristics that affect the production of better friction resistance of the pavement surface in this work. The micro-texture and macro-texture of the asphalt surface of Baghdad Airport highway were studied using two methods: (sand patch method and the British pendulum test). The sand patch was examined by drawing sand grains of a specific volume, while the micro-texture was analyzed using a BPT under dry and wet surface conditions. All data obtained from the two examinations were analyzed and modelled statistically using SPSS 25 software. Results show that skid resistance of pavemen
... Show MoreThe Mesopotamian soil is muddy and fertile, and so from ancient eras Iraqis used mud in their building, settlements and architecture in different methodologies according to the nature and the function of the building that was either in its pure form or by mixing it with other materials such as straw . also as raw bricks in different ways either for the whale building or parts of it, or for the finishing parts such as roofing for instance. In this research these different forms and methodologies will permeate through out a chosen examples of historical building, rural buildings and settlements and ancient buildings as well as some current uses of mud in the structures and building in standing cities, this in order to conclude some
... Show MoreBackground: Osteogenesis imperfecta (OI) is a rare congenital condition that results in bone fragility, recurrent fractures, and various extra-skeletal manifestations. Currently, intravenous bisphosphonate is the mainstay of medical treatment in OI. Objective: To identify the effect of current management strategies on Iraqi children diagnosed with OI. Methods: A retrospective study enrolled OI patients who were registered in Central Child Teaching Hospital, Baghdad, Iraq, from January 2015 to December 2022. We enrolled confirmed OI cases (either clinically and/or radiologically) who received cyclic pamidronate therapy for at least 3 cycles. They neither received other types of bisphosphonates nor underwent surgical intervention. Res
... Show MoreThe aim of this paper is to measure the characteristics properties of 3 m radio telescope that installed inside Baghdad University campus. The measurements of this study cover some of the fundamental parameters at 1.42 GHz. These parameters concentrated principally on, the system noise temperature, signal to noise ratio and sensitivity, half power beam width, aperture efficiency, and effective area. These parameters are estimated via different radio sources observation like Cas-A, full moon, sky background, and solar drift scan observations. From the results of these observations, these parameters are found to be approximately 64 K, 1.2, 0.9 Jansky, 3.7°, 0.54, and 3.8 m2 respectively. The parameters values have vital affect to quantitativ
... Show MoreIn this paper,the homtopy perturbation method (HPM) was applied to obtain the approximate solutions of the fractional order integro-differential equations . The fractional order derivatives and fractional order integral are described in the Caputo and Riemann-Liouville sense respectively. We can easily obtain the solution from convergent the infinite series of HPM . A theorem for convergence and error estimates of the HPM for solving fractional order integro-differential equations was given. Moreover, numerical results show that our theoretical analysis are accurate and the HPM can be considered as a powerful method for solving fractional order integro-diffrential equations.
... Show MoreGenerally, statistical methods are used in various fields of science, especially in the research field, in which Statistical analysis is carried out by adopting several techniques, according to the nature of the study and its objectives. One of these techniques is building statistical models, which is done through regression models. This technique is considered one of the most important statistical methods for studying the relationship between a dependent variable, also called (the response variable) and the other variables, called covariate variables. This research describes the estimation of the partial linear regression model, as well as the estimation of the “missing at random” values (MAR). Regarding the
... Show MoreAbstract: The premise of the study is that populism is a process of building political views and critical intellectual orientations among the general public. It is transformed into mass beliefs by mobilizing the society ideologically and continuously in order to reach or control the circle of authority. We distributed the study topics to four sections: In the second, we will discuss the contents of contemporary populism and how other forms of populism evolved historically. The third is to discuss the political discourse of populism among the military regimes and the comparative Islamic parties in the Middle East, especially in terms of the essence and the intellectual foundations. The fourth section seeks to examine the characteristics o
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