Preferred Language
Articles
/
alkej-313
Experimental and Theoretical Study for Performance Enhancement of Air Solar Collectors by Using Different Absorbers
...Show More Authors

An experimental and theoretical study has been done to investigate the thermal performance of different types of air solar collectors, In this work air solar collector with a dimensions of (120 cm x90 cm x12 cm) , was tested under climate condition of  Baghdad city with a (43° tilt angel)  by using  the absorber plate (1.45 mm thickness, 115 cm height x 84 cm width), which was manufactured from iron painted with a black matt.

The experimental test deals with five types of absorber:-

 Conventional smooth flat plate absorber , Finned absorber , Corrugated absorber plate, Iron wire mesh on absorber And matrix of porous media  on absorber .

The hourly and average efficiency of the collectors were investigated for three values of mass flow rates (0.016 kg/s to 0.027 kg/s) for each type of collector and then the porosity for the last collector type was tested by changing the porosity of porous media.

A typical air solar collector has been studied Theoretically to build a standard software for testing any type of air solar collectors with local weather data .

From the experimental study  it can be seen  by using some obstacle material to the air flow (fins, corrugated absorber plate, iron wire mesh porous media on the absorber) could be enhanced the efficiencies not less than 4 %  for  finned type and 8 % for corrugated and 25 % for mesh and 30  %  for porous media comparing with flat plate (smooth) collector .

Theoretically, the results showed that the collector with high convention heat transfer coefficient porous media has high  hourly efficiency about (η = 56 %) and iron wire mesh on absorber ( η = 52 % ), on the other  side the minimum  performance occurred in the  flat plate absorber  (η = 28  %).

Comparison of results reveals that the theoretical predictions agree reasonably well with experimental results. And the difference between the theoretical   and experimental efficiency in general was between (1─ 15 %).

View Publication Preview PDF
Quick Preview PDF
Publication Date
Fri May 01 2020
Journal Name
Journal Of Engineering
Parametric Study on Unconnected Piled Raft Foundation Using Numerical Modelling
...Show More Authors

Piled raft is commonly used as foundation for high rise buildings. The design concept of piled raft foundation is to minimize the number of piles, and to utilize the entire bearing capacity. High axial stresses are therefore, concentrated at the region of connection between the piles and raft. Recently, an alternative technique is proposed to disconnect the piles from the raft in a so called unconnected piled raft (UCPR) foundation, in which a compacted soil layer (cushion) beneath the raft, is usually introduced.  The piles of the new system are considered as reinforcement members for the subsoil rather than as structural members. In the current study, the behavior of unconnected piled rafts systems has been studie

... Show More
View Publication Preview PDF
Crossref (11)
Crossref
Publication Date
Wed Dec 13 2017
Journal Name
Al-khwarizmi Engineering Journal
A Comparison Between Recursive Least-Squares (RLS) and Extended Recursive Least-Squares (E-RLS) for Tracking Multiple Fast Time Variation Rayleigh Fading Channel
...Show More Authors

In order to select the optimal tracking of fast time variation of multipath fast time variation Rayleigh fading channel, this paper focuses on the recursive least-squares (RLS) and Extended recursive least-squares (E-RLS) algorithms and reaches the conclusion that E-RLS is more feasible according to the comparison output of the simulation program from tracking performance and mean square error over five fast time variation of Rayleigh fading channels and more than one time (send/receive) reach to 100 times to make sure from efficiency of these algorithms.

View Publication Preview PDF
Publication Date
Wed Jun 01 2022
Journal Name
International Journal Of Agricultural And Statistical Sciences
EFFECT OF CULTIVATION DATES AND DIFFERENT SOURCES OF SOIL FERTILIZATION ON VEGETATIVE CHARACTERISTICS, QUALITY AND YIELD OF BROCCOLI
...Show More Authors

This field experiment was conducted at Research Station B, Department of Horticulture and Landscape Engineering, College of Agricultural Engineering Sciences, University of Baghdad, Jadiriyah during the fall season of 2019-2020 to evaluate the effect of cultivation dates and soil fertilization source on the growth, yield and quality of broccoli. A split plot design within the RCBD design with three replicates was applied as the Max F1 hybrid broccoli seedlings were transferred to the field at two dates 25, Sep. 2019 and 15, Oct. 2019, which were symbolized as A and B, respectively, and occupied at the main plot. After two weeks of cultivation, the soil fertilizers were applied three times during the season in 20 days between each applicati

... Show More
Preview PDF
Scopus (8)
Scopus
Publication Date
Mon Nov 01 2021
Journal Name
Transportation Geotechnics
Evaluation of permanent deformation and resilient modulus of pavement base with different gradations and percentages of clay plasticiser
...Show More Authors

View Publication
Scopus (5)
Crossref (6)
Scopus Clarivate Crossref
Publication Date
Wed Dec 11 2019
Journal Name
Journal Of The College Of Education For Women
The Effectiveness of Teaching Program Based on The Theory of Multiple Intelligence in the Development of Literary Thinking Among Students
...Show More Authors

The research aims to know the effectiveness of a training program based on multiple intelligence theory in developing literary thinking among students of the Arabic Language Department at Ibn Rushd School of Humanities and to achieve the goal of research, the Safaris Research Institute, and the research community of Arabic language students in the Faculty of Education the third section of Arabic Language: The research sample consists of (71) students. Divided into (35) students in the experimental group and (36) students in the control group, the researcher balanced between the two groups with variables (intelligence, testing of tribal literary thinking, and time age in months), and after using the T-test for two independent samples, the

... Show More
View Publication Preview PDF
Publication Date
Tue Dec 29 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Personal tax exemptions "a comparative study with some Arab and European system legislations
...Show More Authors

This research aims primarily to highlight personal tax exemptions A comparative study with some Arab and European regulations. And by conducting both theoretical comparative analyses. Most important findings of the study is the need to grant personal and family exemptions that differ according to the civil status of the taxpayer (single or married). In other words, the exemption increases as the number of family members depend on its social sense. Also taking into account some incomes that require a certain effort and looking at the tax rates, it is unreasonable for wages to be subject to the same rates applied to commercial profits.      

View Publication Preview PDF
Publication Date
Thu Jan 31 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Activity, Profitability Indictors Analysis: A Comparsion Study among Nationality and Iraqi Insurance Company
...Show More Authors

Reseach target the most important topic, is Activity and ProfitabilityIndictors Analysis for
Nationality and Iraqi Insurance Company, In order to stand on them ability to cover its risks
and explore the efficiency asset and its avialible resources using to determine them abilities to
profit generation from its insurance activity. The analysis was focus to examine their profit
and activity power, and test the significant differences aming them performance. Test 2
hypothese that is related and result it sign that the 2 company no has significant differences at
profitability and activity level. The research depend on coneclusion, recommended two
company to work at efficiency with cost element of insurance activity in or

... Show More
View Publication Preview PDF
Crossref
Publication Date
Fri Dec 31 2021
Journal Name
Political Sciences Journal
Pakistan: The most dangerous terrorist extremism hotbed (a study information, limitations, and factors)
...Show More Authors

   Receipt date:10/27/2021    accepted date:12/15/2021     Publication date:31/12/2021

        Creative Commons License This work is licensed under a Creative Commons Attribution 4.0 International License.

The phenomenon of extremist extremism (terrorism) was one of the most prominent issues that took a large space in the twenty-first century, in which cognitive motives were mixed with strategic and ideological motives, leading to the emergence of terrorist extremi

... Show More
View Publication Preview PDF
Crossref
Publication Date
Mon Nov 20 2028
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
DETERMINATION OF OPTIMAL CONDITIONS FOR CAROTENOIDS PRODUCTION BY CHEMICAL MUTANAT LOCAL ISOLATE RHODOTORUL MUCILAGENOSA M.: DETERMINATION OF OPTIMAL CONDITIONS FOR CAROTENOIDS PRODUCTION BY CHEMICAL MUTANAT LOCAL ISOLATE RHODOTORUL MUCILAGENOSA M.
...Show More Authors

The aim of this study was to increasing natural carotenoides production by a locally isolate Rodotorula mucilagenosa M. by determination of the optimal conditions for growth and production of this agents, for encouragest to use it in food application permute artificial pigments which harmfull for consumer health and envieronmental. The optimal condition of carotenoides production from Rhodotorula mucilaginosa M were studied. The results shows the best carbon and nitrogen source were glucose and yeast extract. The carotenoids a mount production was 47430 microgram ̸ litter and 47460 microgram ̸ litter, respectively, and the optimum temperature was 30°C, PH 6, that the carotenoides a mount was 47470 microgram ̸ litter and 47670 microgr

... Show More
View Publication Preview PDF
Publication Date
Wed Feb 01 2023
Journal Name
Mathematical Models And Computer Simulations
Function Approximation Technique (FAT)-Based Adaptive Feedback Linearization Control for Nonlinear Aeroelastic Wing Models Considering Different Actuation Scenarios
...Show More Authors

View Publication
Crossref (1)
Crossref