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The Effects of Inclination and Compounds Angles of Round Holes in Staggered Rows on Adiabatic Film Cooling Effectiveness of Vane Suction side
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The aim of this work is oriented to increase film cooling effectiveness value through numerical investigations for flow of Mach number not more than 0.3 around vane surface, to find the effects of inclination and compounds angles of round holes in staggered rows on adiabatic film cooling effectiveness of vane suction side. Multi cylindrical film cooling hole cases were studied with pitch ratio P/d =2 and 3, local blowing ratios M=0.382, 0.77 and 1.14,  inclination angles a=30° and 45°, compound angles β= 0°, 15°, 30° and 45° and local momentum ratios I= 0.084, 0.34 and 0.756  for better cooling process.

            A numerical technique, using ANSYS-FLUENT version 14.5, was used to solve governing partial differential equations of mass, momentum (Navier Stokes equations) and energy conservations in three dimensions with a  turbulence model that involves the solution of the four transport equations. Based on the results of the numerical solution, the best film cooling configuration, blowing ratio, with the range of actual engine flow conditions, dimensions and vane geometry; density ratio 1.74 , temperature ratio 0.57 and blowing ratio M=0.382, 0.77 and 1.14 was obtained. The best case for inclination angle a=30°, P/d=2 was at M=1.14 and β=0° for the total average effectiveness along 60L/d of surface suction side was 0.616, while the best case for inclination angle a=45°, P/d=2 was at M=0.382 and β=30° for the total average effectiveness along 60L/d of surface suction side was 0.516.

            In addition, comparisons were performed with available other work, where the experimental total average effectiveness results of Dees et al., 2011 were in good agreements with the numerical results of current work with a maximum deviation of 9.9% at I=0.34 and 3.6% at I=0.75.

 

 

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Publication Date
Mon Dec 27 2021
Journal Name
Palarch's Journal Of Archaeology Of Egypt/egyptology
Artistic expression in diagnosing behavioral disorders for elementary school students an applied study
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The interest in art for young ages is seen as an obvious breakthrough and as revealing of psychological and health feelings in addition to emotions, and it is a treatment for those who suffer from behavioral disorders. The problem arose with the following question: What is the role of artistic expression in diagnosing behavioral disorders for primary school pupils? The aim of the research is to detect the behavioral disorders in the artistic expression of the female students' paintings from the teachers' point of view. The descriptive analytical approach was adopted as it is the appropriate method for identifying and estimating the characteristics and features related to people, places and things, and analyzing situations or phenomena as a

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Publication Date
Sun Apr 02 2023
Journal Name
Narst 2023 Annual International Conference
Measuring Claim-Evidence-Reasoning Using Scenario-based Assessments Grounded in Real-world Issues
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Improving students’ use of argumentation is front and center in the increasing emphasis on scientific practice in K-12 Science and STEM programs. We explore the construct validity of scenario-based assessments of claim-evidence-reasoning (CER) and the structure of the CER construct with respect to a learning progression framework. We also seek to understand how middle school students progress. Establishing the purpose of an argument is a competency that a majority of middle school students meet, whereas quantitative reasoning is the most difficult, and the Rasch model indicates that the competencies form a unidimensional hierarchy of skills. We also find no evidence of differential item functioning between different scenarios, suggesting

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Publication Date
Sun Sep 07 2014
Journal Name
Baghdad Science Journal
Optimum conditions for ascorbic acid determination in three Iraqi citrus using HPLC technique
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A high-performance liquid chromatography method was employed for the quantitative determination of ascorbic acid (AA) which called vitamin C in three types of Iraqi citrus (orange mandarin and aurantium ) and to establish this goal , evaluation of ascorbic acid degradation is so important due to its significant criticality when exposure to ordinary atmospheric conditions. The chromatographic analysis of AA was carried out after their sequential elution with KH2PO4 ( as mobile phase) by reverse-phase HPLC technique with C8 column and UV detection at 214 nm. .Bad resolutions was appeared clearly for C8 column , so another alternative condition were carried out to improve the resolution by replacement of C8 by C18 column .Statistical treat

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Publication Date
Sun Dec 01 2013
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Obstacles in Marketing Comprehensive Automobile Insurance Policy: بحث أستطلاعي في شركة التأمين الوطنية
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Comprehensive automobile insurance is considered as an important branches in the portfolio of National Insurance Company in Iraq .Due to the continous accidents the company is endeavouring to   this market.

    The company faces several obstacles and limitations in marketing the policies of this portfolio due to certain factors and influences beyond the control of the company and others internal mainly connected with the reduction of the marketing programmes of the company .

    The target of this study is  to focus the light  upon the interal factors which can be gorerned by the company,confronted and solved.

 

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Publication Date
Wed Oct 10 2018
Journal Name
Al-kindy College Medical Journal
Recurrent Laryngeal Nerve Injury With Versus Without Nerve Identification In Different Thyroidectomy Procedures
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Background: The world health organization estimates that worldwide 2 billion people still have iodine deficiency Objectives: Is to make comparison between the effect of identification of recurrent laryngeal nerve (RLN) and non-identification of the nerve on incidence of recurrent laryngeal nerve injury (RLNI) in different thyroidectomy procedures.

Type of the study: cross –sectional study.

Methods: 132 patients with goiters underwent thyroidectomy .Identification of RLN visually by exposure were done for agroup of them and non-identification of the nerves for the other group. The outcomes of RLNI in the two groupsanalyzed statistically for the effect of

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Publication Date
Sun Mar 31 2024
Journal Name
Association Of Arab Universities Journal Of Engineering Sciences
Using Solid Waste as A Substitute for Raw Materials in Construction: A Review.
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The main challenge is to protect the environment from future deterioration due to pollution and the lack of natural resources. Therefore, one of the most important things to pay attention to and get rid of its negative impact is solid waste. Solid waste is a double-edged sword according to the way it is dealt with, as neglecting it causes a serious environmental risk from water, air and soil pollution, while dealing with it in the right way makes it an important resource in preserving the environment. Accordingly, the proper management of solid waste and its reuse or recycling is the most important factor. Therefore, attention has been drawn to the use of solid waste in different ways, and the most common way is to use it as an alternative

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Publication Date
Wed May 10 2023
Journal Name
Journal Of Engineering
ADAPTIVE CYCLIC PREFIX LENGTH FOR CONVOLUITIONAL CODE OFDM SYSTEM IN FREQUENCY SELECTIVE CHANNEL
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Orthogonal Frequency Division Multiplexing (OFDM) is one of recent years multicarrier modulation used in order to combat the Inter Symbol Interference (ISI) introduced by frequency selective mobile radio channel. The circular extension of the data symbol, commonly referred to as cyclic prefix is one of the key elements in an OFDM transmission scheme. This paper study The influence of the cyclic prefix duration on the BER performance of an OFDM-VCPL (Orthogonal frequency division multiplexing - Variable Cyclic Prefix Length) system and the conventional OFDM system with frame 64-QAM modulation is evaluated by means of computer simulation in a multipath fading channel. The adaptation of CP is done with respect to the delay spread estimation

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Publication Date
Mon Jun 15 2020
Journal Name
Al-academy
Cloud platform functionality in visual media: علي صباح سلمان-ثائر علي جبر الله
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The rapid changes in the field of transferring and exchanging information via cloud platforms have revolutionized the field of modern visual media, as cloud computing technology has greatly influenced the media institutions, providing effort, money and high-quality materials. The research included five chapters, the first came under the methodological framework for the research and the second Theoretical framework, the first two included the concept of cloud computing and the second platforms for cloud computing in the visual media and the third chapter Research procedures and the fourth chapter The sample analysis and the fifth chapter The research results were the most prominent
1. The cloud service made the benefit beyond the typic

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Publication Date
Fri Feb 08 2019
Journal Name
Iraqi Journal Of Laser
Urinary Tract Stones Fragmentation using (2100 nm) Holmium: YAG Laser: (In vitro Analysis)
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Urinary stones are one of the most common painful disorders of the urinary system. Four new technologies have transformed the treatment of urinary stones: Electrohydraulic lithotripsy, ultrasonic lithotripsy, extracorporeal shock wave lithotripsy, and laser lithotripsy.The purpose of this study is to determine whether pulsed holmium laser energy is an effective method for fragmenting urinary tract stones in vitro, and to determine whether stone composition affects the efficacy of holmium laser lithotripsy. Human urinary stones of known composition with different sizes, shapes and colors were used for this study. The weight and the size of each stone were measured. The surgical laser system which used in our study is Ho:YAG laser(2100nm)

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Publication Date
Sat Jan 26 2019
Journal Name
Association Of Arab Universities Journal Of Engineering Sciences
Secure Mobile Sink Node location in Wireless Sensor Network using Dynamic Routing Protocol
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The important device in the Wireless Sensor Network (WSN) is the Sink Node (SN). That is used to store, collect and analyze data from every sensor node in the network. Thus the main role of SN in WSN makes it a big target for traffic analysis attack. Therefore, securing the SN position is a substantial issue. This study presents Security for Mobile Sink Node location using Dynamic Routing Protocol called (SMSNDRP), in order to increase complexity for adversary trying to discover mobile SN location. In addition to that, it minimizes network energy consumption. The proposed protocol which is applied on WSN framework consists of 50 nodes with static and mobile SN. The results havw shown in each round a dynamic change in the route to reach mobi

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