Preferred Language
Articles
/
alkej-633
Effects of internal Acoustic Excitation on the Improvement of Airfoil Performance
...Show More Authors

The effect of internal acoustic excitation on the leading-edge, separated boundary layers and the aerodynamic performance of NACA23015 cross section airfoil are examined as a function of excitation location with ranging frequency range (50-400) Hz of the introduced acoustic. Tests are separately conducted in two sections, open type wind tunnels at the Reynolds number of 3.3x105 for measurement at angle of attack (0, 3, 6, 9 &12) deg. and 3x104 for the visualization at angle of attack (12) deg. based on the airfoil chord. Results indicated that the excitation frequency and the excitation location are the key parameters to alter the flow properties and thus to improve the aerodynamic performance. The most effective excitation frequency is found to be equal to the shear layer instability frequency and on excitation location close to the separation point. Moreover, the lift is increased and drag reduced dramatically. The corresponding boundary layers are visualized to be reattached to the surface. 

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri Mar 01 2024
Journal Name
Baghdad Science Journal
Study the Structural Properties of Porous Silicon and their Applications as Thermal Sensors
...Show More Authors

The photo-electrochemical etching (PECE) method has been utilized to create pSi samples on n-type silicon wafers (Si). Using the etching time 12 and 22 min while maintaining the other parameters 10 mA/cm2 current density and HF acid at 75% concentration.. The capacitance and resistance variation were studied as the temperature increased and decreased for prepared samples at frequencies 10 and 20 kHz. Using scanning electron microscopy (SEM), the bore width, depth, and porosity % were validated. The formation of porous silicon was confirmed by x-ray diffraction (XRD) patterns, the crystal size was decreased, and photoluminescence (PL) spectra revealed that the emission peaks were centered at 2q of 28.5619° and 28.7644° for et

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu May 06 2010
Journal Name
Dirasat, Pure Sciences
A Study of the Effects of the Solar Cycle 22, on the Critical Frequencies of F1 Layer over Baghdad
...Show More Authors

This paper aims to study the effects of the long term solar activity on the critical frequencies of ionospheric F1 layer over Baghdad city, during the solar cycle 22, within (1988- 1995). It is found that the critical frequency of this layer is closely related to the sunspots number during the years of the solar cycle 22, at a middle latitude region of the world. The study discussed the effect of sunspot numbers and solar events on the electron densities of F1 layer, which is the most important ionospheric parameter.

Publication Date
Wed Jun 01 2022
Journal Name
Political Sciences Journal
The impact of the Turkish intervention in northern Syria on the Syrian Turkish relations during (2011-2019)
...Show More Authors

This study aimed to provide a theoretical framework for the impact of the Turkish intervention in northern Syria and the extent of its impact on the relations between the two countries.

It also sought to answer the study's main question: What is the impact of the Turkish intervention in northern Syria on Turkish-Syrian relations during the period 2011-2019 ?.   

In this study, the historical method, the descriptive method, and the systems analysis method were used, with the aim of arriving at an accurate and realistic understanding of the Turkish-Syrian relations.

The study reached a set of results, the most important of which was that the Syrian-Turkish relations are based on interests, and that all alliances and

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2023
Journal Name
Aip Conference Proceedings
Study the effect of curved edges on the aerodynamics performance of suction slot
...Show More Authors

View Publication
Scopus Crossref
Publication Date
Wed Apr 01 2015
Journal Name
Journal Of Educational And Psychological Researches
The Effect of Enrichment Programs on the Performance of Gifted Students in KSA
...Show More Authors

       The current study aimed at identifying the impact of each of the full and part time summer enrichment programs on the performance of gifted students. Moreover, it aimed to study the difference between the full and part time programs on the performance of gifted students. The study sample consisted of (115) students from the full time programs and (137) students from the part time programs, they have been randomly selected from the gifted students participating in the full and part time summer enrichment programs. The researcher used the scale of student performance. The results indicated that there were statistically significant differences between the averages of the pre and post applications of the

... Show More
View Publication Preview PDF
Publication Date
Wed Nov 01 2017
Journal Name
Journal Of Economics And Administrative Sciences
A reflection of increased financing Equity on returns commons stocks
...Show More Authors

The research aims to study the effect of an increase in funding the Equity by issuing new common shares on revenues ordinary shares, despite the issuance and marketing costs and the introduction of new shareholders that companies incur when issuing new common shares but it is the most important methods used to finance the Equity is funding the common shares it provides money sufficient to finance the large investments of the company and enhance the confidence of dealers with the company, so I designed this research in order to identify the impact of increased funding Equity issue new common shares to common shares revenues.

This research has included some of the theoretical concepts to each of the Equity

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sat Oct 01 2022
Journal Name
Baghdad Science Journal
A Crime Data Analysis of Prediction Based on Classification Approaches
...Show More Authors

Crime is considered as an unlawful activity of all kinds and it is punished by law. Crimes have an impact on a society's quality of life and economic development. With a large rise in crime globally, there is a necessity to analyze crime data to bring down the rate of crime. This encourages the police and people to occupy the required measures and more effectively restricting the crimes. The purpose of this research is to develop predictive models that can aid in crime pattern analysis and thus support the Boston department's crime prevention efforts. The geographical location factor has been adopted in our model, and this is due to its being an influential factor in several situations, whether it is traveling to a specific area or livin

... Show More
View Publication Preview PDF
Scopus (10)
Crossref (8)
Scopus Clarivate Crossref
Publication Date
Thu Feb 24 2022
Journal Name
Journal Of Educational And Psychological Researches
Social Care for the Disabled students and its influence on the Scientific Level (University of Baghdad as example)
...Show More Authors

The enrollment of students in the university represents a new stage in their life that differ from the previous educational stages that student has previously established. It should be noted that students with special needs at the University of Baghdad are not large numbers. It appears that these students have an excel role in their colleges most often, That is, the handicap was not a barrier to their scientific progress, but rather an incentive for them to excel. The most important conclusion reached by the researcher is that the University of Baghdad had no role in caring for people with special needs and caring for them financially, socially, psychologically, healthily and economically, they need to pay attention to them and take care

... Show More
View Publication Preview PDF
Publication Date
Fri Apr 12 2019
Journal Name
Journal Of Economics And Administrative Sciences
Evaluation of performance of the inspection teams in the appraisal of health situation in Dhi-Qar case research in the Health Department of Dhi-Qar
...Show More Authors

Abstract

Research aims : The aim of the research is to evaluate the reality of the inspection teams' work in the health institutions belonging to Dhi-Qar health office .

Purpose: This research seeks to present a point of view based on knowing the extent of health service quality in Dhi-Qar governorate and discover the role of the inspection teams in enhancing the health service.

Design / Methodology/ Approach: The experimental method has been used and the questionnaire has also been used to collect data in order to develop a reliable and correct measurement model for the research's variables . The research's hypotheses have been tested through using some statistical treat

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Apr 13 2021
Journal Name
Neuroquantology
Sintering Additives Effects on the Microstructure and Electrical Behavior of Yttrium Oxide Ceramic Composites
...Show More Authors

Ceramics type Yttrium oxide with Silicon carbide. were selected to investigate its sintered density, microstructure and electrical properties, after adding V2O5, of 100 nm grain size. Different weight percentages ranging from (0.01,0.02,0.03 and 0.04) were used. Dry milling applied for twelve hours. The pelletized samples were sintered at atmospheric of static air and at sintering temperature 1400 ˚C, for three hours. The crustal structure test shoes the phase which is yttrium silicon carbide Scanning electron microscopy, scan sintered microstructure. Samples after sintering were electrically investigated by measuring its capacitance, dielectric constant and their results showed increasing after added V2O5 particles at the combinat

... Show More
View Publication Preview PDF
Scopus Crossref