Preferred Language
Articles
/
alkej-280
Experimental Study of the Performance of Compound Parabolic Concentrating Solar Collector
...Show More Authors

The design, construction and investigation of experimental study of two compound parabolic concentrators (CPCs) with tubular absorber have been presented. The performance of CPCs have been evaluated by using outdoor experimental measurements including the instantaneous thermal efficiency. The two CPCs are tested instantly by holding them on a common structure. Many tests are conducted in the present work by truncating one of them in three different levels. For each truncation the acceptance half angle (θc) was changed. Geometrically, the acceptance half angle for standard CPC is (26o). For the truncation levels for the other CPC 1, 2 and 3 the acceptance half angle were 20o, 26o and 59o, consequently. A significant difference between the instantaneous thermal efficiency of 3.86× CPC (θc=20o) and 2.32× CPC (θc=26o), and between that for 3.61× CPC (θc=26o) and 2.32× CPC (θc=26o). It's noticed that the difference between the instantaneous thermal efficiency of 2.32× CPC (θc=59o) and 2.32× CPC (θc=26o) is small compared with the difference of the first and second cases, the instantaneous thermal efficiency of 2.32× CPC (26o) was higher than those for other three CPCs. The experimental results show that the maximum thermal efficiency of the full 2.32×CPC (26o) is 0.708, the maximum thermal efficiency of the 3.93×CPC (15o), when it's truncated to 3.84× CPC (20o), 3.61× CPC (26o) and 2.32× CPC (59o)  are 0.51, 0.52 and 0.66, respectively. As the concentration ratio decreases from (3.93× to 1×), the thermal efficiency, energy losses and optical efficiency increase from (0.47 to 63), (1.58 to 7.2 K.m2/W) and (0.494 to 0.797), respectively.

View Publication Preview PDF
Quick Preview PDF
Publication Date
Tue Dec 31 2019
Journal Name
Journal Of Economics And Administrative Sciences
The Reflection of the application TD-ABC approach on profits persistence Applied study in the General State of Hydraulic Industries Factory of Plastic*
...Show More Authors

The interest of many companies has become dealing with the tools and methods that reduce the costs as one of the most important factors of successful companies, and became the subject of the attention of many economic units because of the impact on the profits of company, and since the nineties of the last century the researchers and writers gave great attention to this subject, especially in light of the large competition and rapid developments in cost management techniques, as well as the wide and significant change in production methods that have been directed towards achieving customer satisfaction, all this and more driven by economic units in all sectors whether it is service or productivity to find methods that would reduc

... Show More
View Publication Preview PDF
Crossref
Publication Date
Wed Feb 01 2023
Journal Name
South Asian Journal Of Social Sciences And Humanities
The Impact of the Sustainable Strategy on Strategic Performance: Field Study in the Iraqi Tourism Sector
...Show More Authors

The tourism industry, with its two sides (recreational and religious), is one of the important investment fields in Iraq, it is represented Iraq as the second economic source after the oil sector. So a need for serious efforts to develop the tourism sector and maintain its sustainability. This paper will be one of the important contributions in this field; the paper aims to explore the extent of the impact of the sustainable strategy on the level of overall performance in the Iraqi tourism sector. The field of research was some Iraqi tourist institutions at Iraqi tourism, Which covers the field of study on the one side, and can be studied on the other side, for the developing study methodology and organizing its main parts, the research pap

... Show More
View Publication Preview PDF
Publication Date
Sat Sep 30 2017
Journal Name
Al-khwarizmi Engineering Journal
Study the Effect of Multilayer Single Point Incremental Forming on Residual Stresses for Bottom Plates
...Show More Authors

Abstract

 

Knowing the amount of residual stresses and find technological solutions to minimize and control them during the production operation are an important task because great levels of deformation which occurs in single point incremental forming (SPIF), this induce highly non-uniform residual stresses. In this papera propose of a method for multilayer single point incremental forming with change in thickness of the top plate (0.5, 0.7, 0.9) mm and lubrication or material between two plates(polymer, grease, grease with graphite, mos2) to knowing an effect of this method  and parameters on residual stresses for the bottom plates. Also compare these results for the

... Show More
View Publication Preview PDF
Crossref
Publication Date
Tue Nov 24 2015
Journal Name
Iraqi Journal Of Market Research And Consumer Protection
The role of e-commerce in the insurance industry and its impacts on consumer rights (In the case of the National Insurance Company study): The role of e-commerce in the insurance industry and its impacts on consumer rights (In the case of the National Insurance Company study)
...Show More Authors

The e-commerce is one of the best achievements of the twentieth century, since the conduct commercial transactions via the Internet may be the consumer easy selection process and purchase convenient manner different from traditional methods, and with the beginnings of the new millennium impose the emergence of e-commerce term significant challenges to the insurance industry as an important economic sectors Generally, and insurance companies in particular as a result of scientific development, which has led to a reduction in costs and innovation in the production, which led to intense competition on both levels local or global. The insurance industry is a vital part of the economy and it has a varied impact to the community and individual

... Show More
View Publication Preview PDF
Publication Date
Wed Jan 01 2020
Journal Name
Journal Of Southwest Jiaotong University
Evaluation of Photovoltaic Solar Power of a Dual-Axis Solar Tracking System
...Show More Authors

In this research project, a tip-tilting angle of a photovoltaic solar cell was developed to increase generated electrical power output. An active, accurate, and simple dual-axis tracking system was designed by using an Arduino Uno microprocessor. The system consisted of two sections: software and apparatus (hardware). It was modified by using a group of light-dependent resistor sensors, and two DC servo motors were utilized to rotate the solar panel to a location with maximum sunlight. These components were arranged in a mechanical configuration with the gearbox. The three locations of the solar cell were chosen according to the tilt angle values, at zero angles, which included an optimal 33-degree angle for the Baghdad location and

... Show More
View Publication Preview PDF
Crossref (4)
Crossref
Publication Date
Sat Dec 01 2012
Journal Name
Journal Of Economics And Administrative Sciences
Business incubators the entrance of organizations to shift towards pioneering performance a study by a number of employees of the technical education organizations in mosul
...Show More Authors

     The importance of this research is due to its importance goals, Which are about the attempt of researchers to investigate the probability of depending on businesses, environments to transform organizations, performance in away that enhance the leading  role of organizations  in their environments , and through views of a number of the staff working in the foundation of technical institutes in Mosul.  .

     After deciding the methodology of the study that ,in one hand ,performs the goals of the study , and achieving a suitable theoretical framework to present the concepts of businesses, environments and the leadin

... Show More
View Publication Preview PDF
Crossref (2)
Crossref
Publication Date
Fri Mar 01 2024
Journal Name
Egyptian Journal Of Aquatic Biology And Fisheries
Carbon Sources and Riverine Algal Biomass: An Experimental Study
...Show More Authors

A lotic ecosystem is considered a source of carbon dioxide (CO2) in the atmosphere where it becomes supersaturated with CO2, which contributes to the global carbon cycle. To enhance our comprehension of the roles of CO2 in rivers, an outdoor experiment was designed with controlled carbon source inputs to investigate the roles of the dissolved organic carbon (DOC) and dissolved inorganic carbon (DIC) in the phytoplankton community. Plastic enclosures were installed in the Tigris River within Baghdad for that goal. Samples were collected on the first day, as well as on the 5th and the 12th days from 14 enclosures. The enclosures were treated by artificial glucose (C6H12O6) (10, 20, 30mg/ l) as DOC sources, while sodium bicarbonate (NaHCO3) (1

... Show More
View Publication
Scopus (1)
Scopus Crossref
Publication Date
Mon Dec 05 2022
Journal Name
Baghdad Science Journal
Influence of Optical Fiber Diameters on the Performance of Surface Plasmon Resonance Sensor
...Show More Authors

In this research, a sensor for chemical solutions was designed and formed using optical fiber-based on a surface Plasmon resonance technology. A single-mode optical fiber with three different diameters (25, 45 and 65) µm was used, respectively.  The second layer of the low refractive fiber was replaced by gold, which was electrically deposited at 40 µm thickness. For each of the three types of optical fiber, different saline concentrations (different index of refraction) were used to evaluate the performance of the refractive index sensor (chemical sensor) by measuring its sensitivity and resolutions. The highest values we could get for these two parameters were 240mm/RIU, and 6*10-5 RIU respectively, when the diameter of a

... Show More
View Publication Preview PDF
Scopus (7)
Crossref (8)
Scopus Crossref
Publication Date
Sun Mar 01 2009
Journal Name
Journal Of Economics And Administrative Sciences
Methods of forecasting demandOn the blood substanceApplied study at the National Blood Transfusion Center
...Show More Authors

The current research deals with short term forecasting of demand on Blood material, and its' problem represented by increasing of forecast' errors in The National Center for Blood Transfusion because using inappropriate method of forecasting by Centers' management, represented with Naive Model. The importance of research represented by the great affect for forecasts accuracy on operational performance for health care organizations, and necessity of providing blood material with desired quantity and in suitable time. The literatures deal with subject of short term forecasting of demand with using the time series models in order to getting of accuracy results, because depending these models on data of last demand, that is being sta

... Show More
View Publication Preview PDF
Crossref
Publication Date
Sun Apr 08 2018
Journal Name
Al-khwarizmi Engineering Journal
Study the Effect of Welding Heat Input on the Microstructure, Hardness, and Impact Toughness of AISI 1015 Steel
...Show More Authors

In the present study, MIG welding is carried out on low carbon steel type (AISI 1015) by using electrode ER308L of 1.5mm diameter with direct current straight polarity (DCSP). The joint geometry is of a single V-butt joint with one pass welding stroke for different plate thicknesses of 6, 8, and 10 mm. In welding experiments, AISI 1015 plates with dimensions of 200×100mm and edge angle of 60o from both sides are utilized. In this work, three main parameters related to MIG welding process are investigated, which are welding current, welding speed, heat input and plate thickness, and to achieve that three groups of plates are employed each one consists of three plates. The results indicate that increasing the weld heat input (t

... Show More
View Publication Preview PDF