Preferred Language
Articles
/
joe-1267
Numerical Study for HAWT Wake shape with different Angles of Attack
...Show More Authors

Increasing world demand for renewable energy resources as wind energy was one of the goals behind research optimization of energy production from wind farms. Wake is one of the important phenomena in this field. This paper focuses on understanding the effect of angle of attack (α) on wake characteristics behind single horizontal axis wind turbines (HAWT). This was done by design three rotors different from each other in value of α used in the rotor design process. Values of α were (4.8˚,9.5˚,19˚). The numerical simulations were conducted using Ansys Workbench 19- Fluent code; the used turbulence model was (k-ω SST). The results showed that best value for extracted wind energy was at α=19˚, spread distance of wake behind single HAWT was inversely proportional with α value. Highest turbulence intensity level was in small values of α =4.8֯ and 9.5֯, which explain presence of meandering phenomenon in these two cases on contrast of α=19֯, while symmetry in wake shape was more obvious in α=19֯ than other cases due to the moderate turbulence intensity which was found in this case, which indicates that lowest aerodynamics loads on rotor components was in α=19˚. So best distribution for turbines in farm could be achieved at use high values of α in comparison to low values.

 

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Jun 13 2023
Journal Name
Journal Of Survey In Fisheries Sciences
Spectrum Analyzing X-ray Data Image (FITS) Using Ds9 Program
...Show More Authors

n this study, data or X-ray images Fixable Image Transport System (FITS) of objects were analyzed, where energy was collected from the body by several sensors; each sensor receives energy within a specific range, and when energy was collected from all sensors, the image was formed carrying information about that body. The images can be transferred and stored easily. The images were analyzed using the DS9 program to obtain a spectrum for each object,an energy corresponding to the photons collected per second. This study analyzed images for two types of objects (globular and open clusters). The results showed that the five open star clusters contain roughly t

... Show More
View Publication Preview PDF
Publication Date
Mon May 27 2019
Journal Name
Al-academy
Virtual Museums: Features and Characteristics: وعد عدنان محمود
...Show More Authors

This research provides a study of the virtual museums features and characteristics and contributes to the recognition of the diversity of visual presentation methods, as the virtual museums give the act of participation and visual communication with programs at an open time, so that it would contribute to reflection, thinking and recording notes, developing the actual and innovative skills through seeing the environments. The study has been divided into two sections the first one is virtual museum techniques. The techniques were studied to reach the public and are used remotely by the services of personal computers or smart phones being virtual libraries that store images and information that was formed and built in a digital way and how

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Jan 01 2017
Journal Name
International Journal Of Economic Research
Credit derivatives: Do they matter to avoid credit exposure? (Some evidences from the US market)
...Show More Authors

Credit derivatives (CDs) have been increasingly acknowledged as an important requirement to hedge and transfer credit risk CR. Nonetheless, they have been extensively criticized for destabilizing the whole economic system bringing about the latest subprime credit crisis. The study’s main aim is to investigate the reason for the use of (CDs), whether it is used for hedging or trade purpose, for four of the US international financial institutions that had made it through the 2007 crisis to resume functioning post-crisis. This will be for three different and critical periods, namely the pre, during and after crisis periods (Q1, 2000-Q1, 2014). Adopting the SUR technique, the investigation of the factors that influence the net position of (CD

... Show More
Scopus (2)
Scopus
Publication Date
Mon Jul 01 2013
Journal Name
Iraqi Journal Of Agricultural Sciences مجلة العلوم الزراعية العراقية
EFFECT OF HARROW TYPE AND DRILL SEEDER'S SPEEDS AND DEPTHS ON SOME MACHINERY UNIT TECHNICAL, ECONOMICAL AND ENERGY REQUIREMENT INDICATORS تأثير نوع المنعمة وسٌرع وأعماق البذار في بعض المؤشرات الفنية والأقتصادية ومتطلبات القدرة للوحدة الميكنية
...Show More Authors

Publication Date
Fri Dec 30 2016
Journal Name
Al-kindy College Medical Journal
Deep Vein Thrombosis Predisposing Factors Analysis Using Association Rules Mining
...Show More Authors

Background: DVT is a very common problem with a very serious complications like pulmonary embolism (PE) which carries a high mortality,and many other chronic and annoying complications ( like chronic DVT, post-phlebitic syndrome, and chronic venous insufficiency) ,and it has many risk factors that affect its course, severity ,and response to treatment. Objectives: Most of those risk factors are modifiable, and a better understanding of the relationships between them can be beneficial for better assessment for liable pfatients , prevention of disease, and the effectiveness of our treatment modalities. Male to female ratio was nearly equal , so we didn’t discuss the gender among other risk factors. Type of the study:A cross- secti

... Show More
View Publication Preview PDF
Publication Date
Wed Nov 05 2025
Journal Name
Al–bahith Al–a'alami
International Public Relations methods in building the state's image through Cyberspace
...Show More Authors

The researcher has studied in his research (International Public Relations methods in building the state's image through Cyberspace)
, analytical study of the Facebook and twitter pages for British foreign office , the role was played by the International Public Relations in building the mental image of British , especially after the new media and internet have became influential role in political life . and became an important tools used by political institutions as ministries of foreign affairs in the twenty: one century .
The researcher identified the problem of this study with the following question:
(what is the role of the International Public Relations in building the mental image of state through Cyberspace)
To answer

... Show More
View Publication Preview PDF
Crossref (1)
Crossref
Publication Date
Tue Jan 01 2019
Journal Name
Al-dhad Book Store And Publishing
Calculus part 2
...Show More Authors

This book includes four main chapters: 1. Indefinite Integral. 2. Methods of Integration. 3. Definite Integral. 4. Multiple Integral. In addition to many examples and exercises for the purpose of acquiring the student's ability to think correctly in solving mathematical questions.

Publication Date
Wed Jun 30 2021
Journal Name
Journal Of Planner And Development
Urban wetlands and their impact on city sustainability
...Show More Authors

Urban wetlands are one of the complex systems that provide many economic, social and environmental services to the city. In this research, the most important services provided by urban wetlands from the point of view of the urban planner were reviewed, and the types of these lands and their divisions according to the type of services provided by each type were presented. Environmental is represented in its ability to reduce the dangers of floods, mitigate the climate and reduce its negative impacts, purify water and deplete a lot of suspended impurities and pollutants, and social services such as recreational areas and beautiful landscapes that inspire joy and reassurance in the soul, as well as cultural areas and sports activities for m

... Show More
View Publication Preview PDF
Publication Date
Mon Jan 01 2018
Journal Name
Al-dhad Book Store And Publishing
Calculus part 1
...Show More Authors

This book includes three main chapters: 1. Functions & Their Derivatives. 2. Minimum, Maximum and Inflection points. 3. Partial Derivative. In addition to many examples and exercises for the purpose of acquiring the student's ability to think correctly in solving mathematical questions.

Publication Date
Tue Dec 30 2014
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Comparison between Electroplating and Electroless on Plastic Surface
...Show More Authors

 

We report a method of converting non-conductive plastic surfaces into conductive by plating either copper electroless or copper electroplating -carbon black containing bending Agent onto Perspex plastics . Various approaches have been studied in order to comparing properties of the plated copper for two methods such as scanning electron microscopy (SEM),thickness, roughness, porosity, tensile Strength and elongation. The results show that the surface of electroplating was uniform, compact, and continuous and it had an obvious metallic sheen, while the surface of plated copper for electroless for it had many pores. Also observed that the coating was composed of small cells. Thes

... Show More
View Publication Preview PDF