Preferred Language
Articles
/
bsj-2837
Study the Effect of Solar Radiation Pressure at Several Satellite Orbits
...Show More Authors

The effects of solar radiation pressure at several satellite (near Earth orbit satellite, low Earth orbit satellite, medium Earth orbit satellite and high Earth orbit satellite ) have been investigated. Computer simulation of the equation of motion with perturbations using step-by-step integration (Cowell's method) designed by matlab a 7.4 where using Jacobian matrix method to increase the accuracy of result.

Crossref
View Publication Preview PDF
Quick Preview PDF
Publication Date
Mon Jan 01 2018
Journal Name
American Institute Of Physics
Fabrication of AgInSe2 heterojunction solar cell
...Show More Authors

Abstract. Silver, Indium Selenium thin film with a thickness (5001±30) nm, deposited by thermal evaporation methods at RT and annealing3temperature (Ta=400, 500 and 600) K on a substrate of glass to study structural and optical properties of thin films and on p-Si wafer to fabricate the AgInSe2/p-Si heterojunction solar cell. XRD analysis shows that the AgInSe2 (AIS) deposited film at RT and annealing3temperature (Ta=400, 500 and 600) K have polycrystalline structure. The average grain size has been estimated from AFM images. The energy gap was estimated from the optical transmittance using a spectrometer type (UV.-Visible 1800 spectra photometer). From I-V characterization , the photovoltaic parameters such as, open-circuit voltage, short

... Show More
Preview PDF
Scopus (5)
Scopus
Publication Date
Thu Oct 25 2018
Journal Name
Al–bahith Al–a'alami
War Reporters In Iraqi Satellite Channels And Its Role In Increasing Understanding Of The Audience Of The News .: Field Study For The Reporters And The Audiences In Baghdad For The Period From 1/07/2014 Till – 1/11/2014
...Show More Authors

The importance of media coverage in the war remains dependent on many indicators for its success, the most important is to have qualified reporters who carry the war news professionally. The idea of this research is to determine the role played by war correspondents working on Iraqi satellite channels during the war against ISIS.
The researcher has chosen ( 40 ) reporters those who was able to contact them and prepared a questionnaire for them to study their situations. Also, he chose an intentional sample from Baghdad audience on condition they should be informed by the performance of the reporters in the satellite channels applying the hypotheses of the theory of depending upon media.
The most important results reached by the re

... Show More
View Publication Preview PDF
Crossref
Publication Date
Thu Jan 31 2019
Journal Name
Journal Of Engineering
Experimental Study on Double-Pass Solar Air Heater with and without using Phase Change Material
...Show More Authors

In this paper, an experimental study was conducted to enhance the thermal performance of a double-pass solar air heater (SAH) using phase change material (PCM) for thermal storage at climatic conditions of Baghdad city - Iraq. The double-pass solar air heater integrated with thermal storage system was manufactured and tested to ensure that the air heating reserved after the absence of the sun. The rectangular cavity filled with paraffin wax was used as a latent heat storage and incorporated into the lower channel of solar air heater. Experiments were carried out to evaluate the charging and discharging characteristics of two similar designed solar air collectors with and without using phase change material at a constant

... Show More
View Publication Preview PDF
Crossref (25)
Crossref
Publication Date
Mon Mar 01 2010
Journal Name
Journal Of Economics And Administrative Sciences
The study of the effect of the use of programming in the linear programming model (applied study)
...Show More Authors

The parametric programming considered as type of sensitivity analysis. In this research concerning to study the effect of the variations on linear programming model (objective function coefficients and right hand side) on the optimal solution. To determine the parameter (θ) value (-5≤ θ ≤5).Whereas the result، the objective function equal  zero and the decision variables are non basic، when the parameter (θ = -5).The objective function value increases when the parameter (θ= 5) and the decision variables are basic، with the except of X24, X34.Whenever the parameter value increase, the objectiv

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Mar 07 2022
Journal Name
Journal Of Educational And Psychological Researches
The Degree of Academic Leaders Practice at the University of Northern Border for Creative Leadership "Empirical Study"
...Show More Authors

The study aimed to identify the degree of academic leaders practices at the University of Northern Border for creative leadership, which attribute to different variables (nature of work, employer, gender, years of experience in administrative work at the university). To achieve the goal of the study, the researcher used the descriptive approach survey. Therefore, the researcher used a questionnaire as a study tool, which consisted of (40) items that included dimensions (sensitivity to problems, initiative, originality, flexibility). The study sample consisted of (240) participants included (agents of colleges, and supporting deanships, and their employees) during the second semester of the academic year 1439/1440 AH. The results showed t

... Show More
View Publication Preview PDF
Publication Date
Sun Jul 09 2023
Journal Name
Journal Of Engineering
Parametric Study of Active Solar Heating Using a Pebble Bed as a Thermal Collector and Storage Unit
...Show More Authors

In this study, pebble bed as an absorber and storage material was placed in a south facing, flat plate air-type solar collector at fixed tilt angle of (45°). The effect of this material and differ- ent parameters on collector efficiency has been investigated experimentally and
theoretically. Two operation modes were employed to study the performance of the solar air heater. An inte- grated mode of continuous operation of the system during the period of (11:00 am – 3:00 pm) and non-integrated mode in which the system stored the solar energy through the day then used the stored energy during the period of (3:00 pm – 8:00 pm). The results of parametric study in case of continuous operating showed that the maximum average temperatur

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Mon Jan 01 2018
Journal Name
Fme Transaction
The influence of frictional facing thickness on the contact pressure distribution of multi-disc dry clutches
...Show More Authors

Scopus (9)
Crossref (9)
Scopus Crossref
Publication Date
Mon Jan 01 2018
Journal Name
Fme Transaction
The influence of frictional facing thickness on the contact pressure distribution of multi-disc dry clutches
...Show More Authors

Frictional heat is generated when the clutch starts to engag. As a result of this operation the surface temperature is increased rapidly due to the difference in speed between the driving and driven parts. The influence of the thickness of frictional facing on the distribution of the contact pressure of the multi-disc clutches has been investigated using a numerical approach (the finite element method). The analysis of contact problem has been carried out for a multiple disc dry clutch (piston, clutch discs, separators and pressure plate). The results present the distribution of the contact pressure on all tShe surfaces of friction discs that existed in the friction clutch system. Axisymmetric finite element models have been developed to ac

... Show More
View Publication
Scopus (9)
Crossref (9)
Scopus Clarivate Crossref
Publication Date
Thu Oct 29 2020
Journal Name
The 11th International Renewable Energy Congress (irec 2020)
Thermal efficiency Optimization of the evacuated tube solar water heater system by using mirror flat reflector
...Show More Authors

In this paper a comparison of the experimental of evacuated tube solar water heater systems with and without mirror flat reflector. The aim of using the reflector to improve thermal efficiency, and the data gathered which are (temperature, solar irradiation and time) for three days were compared. the results from compared data the temperature lower increase in evacuated tube solar water heater system without reflector than the temperature increase in evacuated tube solar water heater system with reflector .The results show (53, 39, 35) % for three days respectively that the evacuated tube solar water heater system with reflector has higher thermal efficiencies than the results (47, 28, 30) % for three days respectively thermal efficiencies

... Show More
View Publication
Crossref (4)
Crossref
Publication Date
Sun Jul 19 2026
Journal Name
Al–bahith Al–a'alami
TOPICS OF PEACEFUL COEXISTENCE IN FOREIGN SATELLITE CHANNELS DIRECTED IN THE ARABIC LANGUAGE: (A Research Drawn from Master Thesis)
...Show More Authors

This research deals with issues of peaceful coexistence in foreign satellite channels directed in the Arabic language, trying to get acquainted with the most prominent of these topics dealt with the programs subject to analysis and the method of dealing with them and the most used journalistic arts in that.

The research adopted the descriptive approach and the method of content analysis for the purpose of studying the research community represented by the program «Shabab Talk» “Youth Talk” in the German channel Deutsche Welle (DW) and the program «Beina Sam wa Amar» “between Sam and Ammar” in the American free channel, by designing the content analysis form to subject

... Show More
View Publication Preview PDF
Crossref