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joe-2210
Numerical Study of Optimum Configuration of Unconventional Airfoil with Steps and Rotating Cylinder for Best Aerodynamics Performance
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Numerical study of separation control on symmetrical airfoil, four digits (NACA

0012) by using rotating cylinder with double steps on its upper surface based on the computation of Reynolds-average Navier- Stokes equations was carried out to find the optimum configuration of unconventional airfoil for best aerodynamics performance. A model based on collocated Finite Volume Method was developed to solve the governing equations on a body-fitted coordinate system. A revised (k-w) model was proposed as a known turbulence model. This model was adapted to simulate the control effects of rotating cylinder. Numerical solutions were performed for flow around unconventional airfoil with cylinder to main stream velocities ratio in the range of 1 to 4 and for various positions of the steps on the airfoil from the leading edge, 0.1c, 0.2c, 0.3c, 0.4c, 0.5c for the first step and 0.5c, 0.6c, 0.7c, 0.8c for the second step with constant step depth and length of 0.03c and 0.125c respectively. Reynolds number of 700,000 which was based on the cord length (c), with angle of attacks 0, 5, 8, 10, 12, 15 degrees was considered for the assessment of the unconventional airfoil performance. The numerical investigation showed that the optimum configuration for the unconventional airfoil was found to be at velocities ratio (U/U∞=4) with the steps positions at 0.5c and 0.8c for best airfoil performance.

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Publication Date
Sun Dec 12 2010
Journal Name
Journal Of Planner And Development
The effect of pedestrian roads in providing a comfortable environment for humans
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Planning of cities show great attention on streets planning as one of the most structural component foundations for cities, that providing many functional needs and connect parts of the city each other, and work as a commercial and services activities centers. Instead of this highly focused on distributing streets with different streets types such as economical and trading and housing streets. This concerned was only on the dimensions and scales of different types of vehicles and their movement. When scale and dimension and movement of mans were as a second priority in designing and planning streets. Which came's first for traditional streets. The research try to submit some designs guides for planners that contribute in re conce

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Publication Date
Sun Sep 01 2019
Journal Name
Journal Of Physics: Conference Series
Recovery of temporal coefficient for heat equation from non-local overdetermination conditions
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Abstract<p>Recovery of time-dependent thermal conductivity has been numerically investigated. The problem of identification in one-dimensional heat equation from Cauchy boundary data and mass/energy specification has been considered. The inverse problem recasted as a nonlinear optimization problem. The regularized least-squares functional is minimised through lsqnonlin routine from MATLAB to retrieve the unknown coefficient. We investigate the stability and accuracy for numerical solution for two examples with various noise level and regularization parameter.</p>
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Publication Date
Sun Feb 25 2024
Journal Name
Baghdad Science Journal
An Adaptive Harmony Search Part-of-Speech tagger for Square Hmong Corpus
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Data-driven models perform poorly on part-of-speech tagging problems with the square Hmong language, a low-resource corpus. This paper designs a weight evaluation function to reduce the influence of unknown words. It proposes an improved harmony search algorithm utilizing the roulette and local evaluation strategies for handling the square Hmong part-of-speech tagging problem. The experiment shows that the average accuracy of the proposed model is 6%, 8% more than HMM and BiLSTM-CRF models, respectively. Meanwhile, the average F1 of the proposed model is also 6%, 3% more than HMM and BiLSTM-CRF models, respectively.

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Publication Date
Tue Jul 02 2013
Journal Name
Journal Of Baghdad College Of Dentistry
Local Drug Delivery Systems for Treating Periodontal Diseases: A Review of Literature
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Publication Date
Sun Mar 06 2016
Journal Name
Baghdad Science Journal
The Nuclear Structure for Exotic Neutron-Rich of 42, 43, 45,47K Nuclei
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In this paper the proton, neutron and matter density distributions and the corresponding root mean square (rms) radii of the ground states and the elastic magnetic electron scattering form factors and the magnetic dipole moments have been calculated for exotic nucleus of potassium isotopes K (A= 42, 43, 45, 47) based on the shell model using effective W0 interaction. The single-particle wave functions of harmonic-oscillator (HO) potential are used with the oscillator parameters b. According to this interaction, the valence nucleons are asummed to move in the d3f7 model space. The elastic magnetic electron scattering of the exotic nuclei 42K (J?T= 2- 2), 43K(J?T=3/2+ 5/2), 45K (J?T= 3/2+ 7/2) and 47K (J?T= 1/2+ 9/2) investigated t

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Publication Date
Fri Apr 01 2022
Journal Name
Baghdad Science Journal
Positive Definiteness of Symmetric Rank 1 (H-Version) Update for Unconstrained Optimization
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Several attempts have been made to modify the quasi-Newton condition in order to obtain rapid convergence with complete properties (symmetric and positive definite) of the inverse of  Hessian matrix (second derivative of the objective function). There are many unconstrained optimization methods that do not generate positive definiteness of the inverse of Hessian matrix. One of those methods is the symmetric rank 1( H-version) update (SR1 update), where this update satisfies the quasi-Newton condition and the symmetric property of inverse of Hessian matrix, but does not preserve the positive definite property of the inverse of Hessian matrix where the initial inverse of Hessian matrix is positive definiteness. The positive definite prope

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Publication Date
Mon Jun 01 2020
Journal Name
Test Engineering & Management
The Effects of Annealing on SnSe Thin Films for Solar Cells Applications
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The structure, optical, and electrical properties of SnSe and its application as photovoltaic device has been reported widely. The reasons for interest in SnSe due to the magnificent optoelectronic properties with other encouraging properties. The most applications that in this area are PV devices and batteries. In this study tin selenide structure, optical properties and surface morphology were investigated and studies. Thin-film of SnSe were deposit on p-Si substrates to establish a junction as solar cells. Different annealing temperatures (as prepared, 125,200, 275) °C effects on SnSe thin films were investigated. The structure properties of SnSe was studied through X-ray diffraction, and the results appears the increasing of the peaks

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Publication Date
Mon Nov 01 2010
Journal Name
Journal Of Systems And Software
Development of Java based RFID application programmable interface for heterogeneous RFID system
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Publication Date
Mon Mar 08 2021
Journal Name
Baghdad Science Journal
EXTENSION OF HIGH REFLECTANCE BAND WIDTH FOR FAR INFRARED SPECTRAL REGION : (1)
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Extension of bandwidth for high reflectance zone for the spectral region (8-14pm) was studied adapting the concept of contiguous and overlapping high reflectance stacks. Computations was carried out using the modified characteristic matrix theory restricted to near-normal incidence of light on dielectric , homogenous and isotropic symmetrical stack. Certain precautions must be taken in the choice of stacks to avoid deep —reflectance minima from developing within the extended high reflectance region. Results illustrate that the techniques of extending the high reflectance regions are applicable not only to mirrors , but also to short-and long-edge filter and to narrow band pass filters.

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Publication Date
Fri Jul 05 2024
Journal Name
Journal Of Applied Spectroscopy
Spectrophotometric Method Using the Derivative for the Determination of the Drug Losartan
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