Preferred Language
Articles
/
alkej-458
An Experimental Study of the Effect of Vortex Shedding on Solar Collector Performance
...Show More Authors

In this work, the effect of vortex shedding on the solar collector performance of the parabolic trough solar collector (PTSC) was estimated experimentally. The effect of structure oscillations due to wind vortex shedding on solar collector performance degradation was estimated. The performance of PTSC is evaluated by using the useful heat gain and the thermal instantaneous efficiency. Experimental work to simulate the vortex shedding excitation was done. The useful heat gain and the thermal efficiency of the parabolic trough collector were calculated from experimental measurements with and without vortex loading. The prototype of the collector was fabricated for this purpose. The effect of vortex shedding at different operation conditions was examined. The variation of angles of attack and wind velocity leads to different values of vortex loading coefficients and shedding frequencies. The relation between the dynamic characteristics and solar collector performance was evaluated. The finite element method was used to estimate the dynamic characteristic of the solar collector in addition to experimental work to evaluate the relation between the dynamic behavior of the collector and its performance.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
The use of two indicators of market value-added and return on capital invested in measuring the performance of the Iraqi banking sector
...Show More Authors

For a long time, the intensification of profit represented a major goal for the company management ,but this goal confirmed a series of restrictions such the constriction on short period, the time rather than on long and medium strategic goal, the relationships with customers ,the supplies, employees , This goal is replaced by another one (intensification of the company's value) ,and the fortune of the share holders itself ,for the purpose  of creating value, the company must generate  great outcomes to cover the operating expense and to insure the a suitable compensation to the invested capital (the market value added) is  the indication used to estimate the company ability to create value –added the development

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Feb 10 2016
Journal Name
Scientific Reports
Experimental demonstration on the deterministic quantum key distribution based on entangled photons
...Show More Authors

As an important resource, entanglement light source has been used in developing quantum information technologies, such as quantum key distribution(QKD). There are few experiments implementing entanglement-based deterministic QKD protocols since the security of existing protocols may be compromised in lossy channels. In this work, we report on a loss-tolerant deterministic QKD experiment which follows a modified “Ping-Pong”(PP) protocol. The experiment results demonstrate for the first time that a secure deterministic QKD session can be fulfilled in a channel with an optical loss of 9 dB, based on a telecom-band entangled photon source. This exhibits a conceivable prospect of ultilizing entanglement light source in real-life fiber-based

... Show More
View Publication
Scopus (17)
Crossref (16)
Scopus Clarivate Crossref
Publication Date
Sun Mar 01 2015
Journal Name
Journal Of Engineering
Experimental Study of Interior Temperature Distribution Inside Parked Automobile Cabin
...Show More Authors

Temperature inside the vehicle cabin is very important to provide comfortable conditions to the car passengers. Temperature inside the cabin will be increased, when the car is left or parked directly under the sunlight. Experimental studies were performed in Baghdad, Iraq (33.3 oN, 44.4 oE) to investigate the effects of solar radiation on car cabin components (dashboard, steering wheel, seat, and inside air). The test vehicle was oriented to face south to ensure maximum (thermal) sun load on the front windscreen. Six different parking conditions were investigated. A suggested car cover was examined experimentally. The measurements were recorded for clear sky summer days started at 8 A.M. till 5 P.M.

... Show More
View Publication Preview PDF
Publication Date
Sat Feb 02 2019
Journal Name
Journal Of The College Of Education For Women
The Efficctency of the mesopotamian company for seed production
...Show More Authors

0

View Publication Preview PDF
Publication Date
Sat Sep 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Reflection of knowledge workers characteristics on knowledge acquision “Survey Study of the views of a sample of engineers and technicians in the Directorate of Electricity In the city of Sulaymaniyah
...Show More Authors

Purpose: The research aims to diagnose the current availability of knowledge workers characteristics and the role of these characteristics in knowledge acquision in the city of Sulaimaniya Directorate of Electricity, and to identify the differences between personal and occupational characteristics of a sample of research and its impact on the availability of such properties.

Design/methodology/approach :to achieve the objectives of the research questionnaire was developed especially for it and then distributed to a sample of engineers and technicians working in the Directorate of Electricity city of Sulaimaniya, where the sample of the research (52) respondents.

Findings:  the most important conclusions reached

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 23 2022
Journal Name
Innovative Infrastructure Solutions
Experimental modeling of a single pile in liquefiable soil under the effect of coupled static-dynamic loads
...Show More Authors

In this work, a single pile is physically modeled and embedded in an upper liquefiable loose sand layer overlying a non-liquefiable dense layer. A laminar soil container is adopted to simulate the coupled static-dynamic loading pile response during earthquake motions: Ali Algharbi, Halabjah, El-Centro, and Kobe earthquakes. During seismic events with combined loading, the rotation along the pile, the lateral and vertical displacements at the pile head as well as the pore pressure ratio in loose sandy soil were assessed. According to the experimental findings, combined loading that ranged from 50 to 100% of axial load would alter the pile reaction by reducing the pile head peak ground acceleration, rotation of the pile, and lateral displacem

... Show More
Scopus (3)
Crossref (3)
Scopus Clarivate Crossref
Publication Date
Sun Mar 04 2012
Journal Name
Baghdad Science Journal
Effect of alcoholic extract of Adhatoda vasica leaves on some biological performance of Ceratitis capitata larvae
...Show More Authors

Many biological tests were done to study the effect of the crude alcoholic leaves extracts on the biological characteristics at the larvae fruit fly Ceratitis capitata with different concentrations of the extracts exposed 1,2,3,5 and 7.5 % at constant laboratory conditions includes the temperature and the relative humidity (27±2C0&70±5 % respectively). The results of the experiments showed that the alcoholic extracts of the plant effected the growth and the development of the larvae and pupae according to the concentrations . The alcoholic extracts proved to have the highest mortality tend to 66.76 % in larva treated with alcoholic at concentration 7.5 % the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri May 19 2023
Journal Name
Revista Iberoamericana De PsicologÍa Del Ejercicio Y El Deporte
THE EFFECT OF SPECIAL EXERCISES ACCORDING TO A DESIGNED DEVICE IN DEVELOPING THE PERFORMANCE OF A KINETIC CHAIN ON THE BALANCE BEAM DEVICE
...Show More Authors

Preview PDF
Scopus
Publication Date
Sun Dec 01 2019
Journal Name
Al-khwarizmi Engineering Journal
Effect of Pre-Tension and Orientation on the Springback Behavior of the Sheet Brass 65-35
...Show More Authors

One of the most important phenomenon that occurs in sheet metal forming processes is the spring-back, which causes several geometrical alterations in the parts. The accurate prediction of springback after bending unloading is the key to the tool design, operation control, and precision estimate concerning the part geometry. This study investigated experimentally the effect of pretension in three rolling direction (0, 90, 45 degree) on the springback behavior of the yellow brass, sheet under V shape bending die. The pre-tension ranges from five different levels starting of 11% to 55% from the total strain in each rolling direction by regular increase of 11 %, then bent on a V-die 90 degree for the springback estimate. From experiment the

... Show More
View Publication Preview PDF
Publication Date
Sun Feb 10 2019
Journal Name
Iraqi Journal Of Physics
Experimental study for the properties of Fe3O4 dusty plasma using the air in vacuum chamber system
...Show More Authors

In this work, we carried out an experimental study of thedusty
plasma by taking the dust material Fe3O4 with radius of the any grain
0.1μm - 0.5μm. In experiment we use air in the vacuum chamber
system under different low pressure (0.1-1) Torr. The results
illustrated that the present of dust particles in the air plasma did not
effect on Paschen minimum which is 0.5 without dust and with Fe3O4
dusty grains.
The effect of Fe3O4 dust particles on plasma parameters can be
notice in direct current system in glow discharge region. The plasma
parameters which were studied in this work represent plasma
potential, floating potential,electron saturation current, temperatu

... Show More
View Publication Preview PDF
Crossref