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Investigation of Load and Pressure Distribution on Wing with Wake Rollup for Low Speed Aircraft
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The presented work shows a preliminary analytic method for estimation of load and pressure distributions on low speed wings with flow separation and wake rollup phenomena’s. A higher order vortex panel method is coupled with the numerical lifting line theory by means of iterative procedure including models of separation and wake rollup. The computer programs are written in FORTRAN which are stable and efficient.

      The capability of the present method is investigated through a number of test cases with different types of wing sections (NACA 0012 and GA(W)-1) for different aspect ratios and angles of attack, the results include the lift and drag curves, lift and pressure distributions along the wing span taking into the  consideration the effect of the angles of attack and the aspect ratios on the wake rollup. The pressure distribution on the wings shows that there is a region of constant pressure on the upper surface of the wings near the trailing edge in the middle of the wing, also there is a region of flow separation on the upper surface of the wings. A good agreement is found between the presented work results and other from previous researches.

      These results show that the presented method is able to capture much of flow over wings feature like separation and wake rollup. 

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Publication Date
Sun Jun 30 2013
Journal Name
College Of Islamic Sciences
Ruling on dealing with Jews in Muslim countries
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Praise be to God, who is satisfied with Islam as our religion, “He opened a clear conquest for us,” and whoever works with us through the Shari’ah works and protects us. And that our master and Mawlana Muhammad His servant and Messenger is a prophet who has been merciful and compassionate. "
And after:
The occupation of Iraq and the accompanying bone events, and the following severe obstacles, resulted in a set of problems that require legitimate stances, and satisfactory answers, remove confusion and delusion, amid the clash of opinions and contradictions of jurisprudence. Work and application.
Among the difficult problems that surfaced in light of the new political developments on the land of Iraq: (the ruling on dealing

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Publication Date
Sun Dec 05 2010
Journal Name
Baghdad Science Journal
Pre-Test Single and Double Stage Shrunken Estimators for the Mean of Normal Distribution with Known Variance
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This paper is concerned with pre-test single and double stage shrunken estimators for the mean (?) of normal distribution when a prior estimate (?0) of the actule value (?) is available, using specifying shrinkage weight factors ?(?) as well as pre-test region (R). Expressions for the Bias [B(?)], mean squared error [MSE(?)], Efficiency [EFF(?)] and Expected sample size [E(n/?)] of proposed estimators are derived. Numerical results and conclusions are drawn about selection different constants included in these expressions. Comparisons between suggested estimators, with respect to classical estimators in the sense of Bias and Relative Efficiency, are given. Furthermore, comparisons with the earlier existing works are drawn.

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Publication Date
Tue Sep 01 2015
Journal Name
2015 7th Computer Science And Electronic Engineering Conference (ceec)
An experimental investigation on PCA based on cosine similarity and correlation for text feature dimensionality reduction
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Scopus (6)
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Publication Date
Mon May 12 2025
Journal Name
Boundary Value Problems
Minimal wave speed and traveling wave in nonlocal dispersion SIS epidemic model with delay
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This study examines traveling wave solutions of the SIS epidemic model with nonlocal dispersion and delay. The research shows that a key factor in determining whether traveling waves exist is the basic reproduction number R0. In particular, the system permits nontrivial traveling wave solutions for σ≥σ∗ for R0>1, whereas there are no such solutions for σ<σ∗. This is because there is a minimal wave speed σ∗>0. On the other hand, there are no traveling wave solutions when R0≤1. In conclusion, we provide several numerical simulations that illustrate the existence of TWS.

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Scopus (2)
Crossref (2)
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Publication Date
Fri Aug 20 2021
Journal Name
Iraqi Journal Of Laser
Effect of Low Energy Laser on the Healing of Tooth Extraction Wound: (Histological Study in Rat)
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Aims: This study was done to investigate the effect of low energy laser therapy on bone healing at the extraction site. Materials and methods:(24) male albino rats were exposed to the extraction procedure of the maxillary first molar on the first day of a seven day experiment and these animals were divided into two main groups; the control group and the laser group. The laser experiment involved using (Ga-As infrared diode laser) from optodent by directing the probe over the extraction site. The control group consisted of 4 rats, and the laser group was subdivided into 5 subgroups of 4 rats each. The laser dose was as follows: B1: a single dose of 5 minutes immediately after extraction.,

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Publication Date
Thu Mar 31 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Load Effect on Wall Attachment Fluidics Amplifier Performance
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An experimental work has been conducted on wall attachment fluidics amplifiers, one of them to study the effect of output pressure or load on the amplifier performance. The output load has been simulated as a piston connected to the device output and the piston can be loaded accordingly. The results shows that the output volume flow rate increases as the supply pressure increases under different load and the output pressure remains constant as the supply pressure increases under constant load.

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Engineering
Synchronous Buck Converter with Perturb and Observe Maximum Power Point Tracking Implemented on a Low-Cost Arduino-microcontroller
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Maximum power point tracking (MPPT) is used in photovoltaic (PV) systems to enhance efficiency and maximize the output power of PV module, regardless the variation of temperature, irradiation, and the electrical characteristics of the load. A new MPPT system has been presented in this research, consisting of a synchronous DC-DC step-down Buck converter controlled by an Arduino microcontroller based unit. The MPPT process with Perturb and Observe method is performed with a DC-DC converter circuit to overcome the problem of voltage mismatch between the PV modules and the loads. The proposing system has high efficiency, lower cost and can be easily modified to handle more energy sources. The test results indicate that the u

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Publication Date
Thu Dec 28 2017
Journal Name
Al-khwarizmi Engineering Journal
Aircraft Lateral-Directional Stability in Critical Cases via Lyapunov Exponent Criterion
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Based on Lyapunov exponent criterion, the aircraft lateral-directional stability during critical flight cases is presented. A periodic motion or limit cycle oscillation isdisplayed. A candidate mechanism for the wing rock limit cycle is the inertia coupling between an unstable lateral-directional (Dutch roll) mode with stable longitudinal (short period) mode. The coupling mechanism is provided by the nonlinear interaction of motion related terms in the complete set equations of motion. To analyze the state variables of the system, the complete set of nonlinear equations of motion at different high angles of attack are solved. A novel analysis including the variation of roll angle as a function of angle of attack is proposed. Furthermore

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Publication Date
Fri Jan 01 2021
Journal Name
Special Exercises For Offensive Tactical Skills And Their Impact On Developing The Speed And Accuracy Of Some Basic Skills In Youth Football
SPECIAL EXERCISES FOR OFFENSIVE TACTICAL SKILLS AND THEIR IMPACT ON DEVELOPING THE SPEED AND ACCURACY OF SOME BASIC SKILLS IN YOUTH FOOTBALL
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Scopus
Publication Date
Sun Apr 06 2008
Journal Name
Diyala Journal For Pure Science
Preliminary Test Bayesian –Shrunken Estimators for the Mean of Normal Distribution with Known Variance
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