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Experimental Study on the Effect of Insertion of Copper Lessing Rings in Phase Change Material (PCM) on the Performance of Thermal Energy Storage Unit
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Abstract

One of the most suitable materials to be used in latent heat thermal energy storage system (LHTES) are Phase change materials, but a problem of slow melting and solidification processes made many researchers focusing on how to improve their thermal properties. This experimental work concerned with the enhancing of thermal conductivity of phase change material. The enhancing method was by the addition of copper Lessing rings in phase change material (paraffin wax). The effect of diameter for the used rings was studied by using two different diameters (0.5 cm and 1cm). Also, three volumetric percentages of rings addition (3%, 6% and 10%) were tested for each diameter. The discharging process was done with four velocities for each case. The obtained results indicated that the maximum volumetric percentage gave a diminished time for melting and maximized the heat transfer in both PCM and air sides as compare with the case of no rings, but the effect of these rings had lower effect on the solidification time. In case of 1 cm rings diameter minimum time for melting was obtained for both 3% and 6% volumetric percentages as compared with the same percentages in case of 0.5 cm diameter rings, while the latter with 10% volumetric percentage overcomes the 1 cm diameter rings for the same previous percentage. Also it can be seen that the minimum velocity (v=1m/s) gave the utmost outlet temperature and with the maximum one (v=3m/s), the minimum solidification time achieved.

Keyword: Thermal energy storage systems, Latent heat storage, Phase change materials, Heat transfer enhancement.

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Publication Date
Thu Nov 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Technological Change in Process Design Decisions (Applied study in an organization)
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Abstract:

     Due to the importance of technology and the accompanying changes of the environment affecting companies that use the technology mainly in their work, especially as most companies live in an unstable dynamic environment, which motivated the researchers to choose the International Company for smart card (Keycard) as a field of research and find ways to them to face Those changes.

     The problem of the study was "limited attention to the components of technological change", which included research and development, innovation and information technology, which had an impact on the design decisions of the process (process selection, cust

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Publication Date
Tue Jun 30 2020
Journal Name
Journal Of Economics And Administrative Sciences
Financing and its impact on municipal performance in the municipalities of Missan governorate for the period (2011-2018)
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The research aims to show the role or extent of the impact of financing in its various forms on the municipal performance before and after the financial deficit through relying on the analytical research methodology of the research community represented by the Directorate General of Municipalities and the Directorate of Maysan municipalities as a sample of research (13) municipal institutions for a period of (8) years, Considering the completion of the final accounts of these years, which provides the necessary data for the study, in addition to the variation in the quality and amounts of grants allocated to municipal institutions during these years, which gives a clearer and more comprehensive picture of the reality of allocatio

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Publication Date
Sun Mar 19 2023
Journal Name
Journal Of Educational And Psychological Researches
The Effect of the Alternative Evaluation Strategy on the Achievement of Fourth-Grade Female Science Students in the Subject of Biology
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Abstract

The aim of the current research is to identify the Effect of the alternative evaluation strategy on the achievement of fourth-grade female students in the subject of biology. The researchers adopted the zero hypothesis to prove the research objectives, which is there is no statistically significant difference at the level (0.05) between the average scores of the experimental group who study according to the alternative evaluation strategy and the average scores of the control group who study in accordance with the traditional method. The researchers selected the experimental partial adjustment design of the experimental and control groups with the post-test. The researchers intentionally selected (Al-fed

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Publication Date
Thu Mar 30 2023
Journal Name
Journal Of Economics And Administrative Sciences
The Effect of Internal Marketing on Organizational Citizenship Behavior
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The aim of this paper is to determine the effect of internal marketing through three dimensions: vision, development, and reward - on organizational citizenship behavior in three private universities in Iraq. Organizations’ view of their members as internal customers could be made them more realistic in dealing with the reasons for leaving and going to other organizations. This can promote business organizations to build an organizational environment that contributes to making the organization look like the homeland of those workers. The research method is descriptive and analytical. The tool for data collection was the questionnaire. Statistical software (SPSS V.23 and AMOS V.23) was used to analyze the data. The research sample was r

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Publication Date
Sat Jun 30 2018
Journal Name
Kufa Journal For Agricultural Sciences
Effect of numbers of blades and speed of tillage in the performance of the rotavator plow
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Experiment Factorial conducted with two factor in field texture silt clay loam soil, the first factor were Two Rotavator plow which different in number of rotary blades on flanges, weight, width, made and type, the second factor were four speeds tractor 2.62, 5.10, 7.55, 9.23 km/hr to compare performance two Rotavator under depth 12 cm and knowledge slippage, distance between beat blades, practical productivity, disturbed soil volume, percentage of the soil clods which have diameter less than 5 cm under complete block design with three replications using Least Significant Design 0.05. Results showed Galucho Rotavator recorder the higher practical productivity 0>7089 ha/hr, disturbed soil volume 809.8 m3/hr, percentage of the soil clods 96.1

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Publication Date
Sat Mar 01 2008
Journal Name
Al-khwarizmi Engineering Journal
Study the Effect of Carbon Fiber Volume Fraction and their Orientations on the Thermal Conductivity of the Polymer Composite Materials.
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      The effect of fiber volume fraction of the carbon fiber on the thermal conductivity of the polymer composite material was studied. Different percentages of carbon fibers were used (5%, 10%, 15%, 20%, and 25%). Specimens were made in two groups for unsaturated polyester as a matrix and carbon fibers, first group has parallel arrangement of fibers and the second group has perpendicular arrangement of fibers on the thermal flow, Lee's disk method was used for testing the specimens. This study showed that the values of the of thermal conductivity of the specimens when the fibers arranged in parallel direction was higher than that when the fibers arranged in the perpendicular direction  

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Publication Date
Mon Aug 01 2016
Journal Name
Journal Of Economics And Administrative Sciences
The Role of Moral Intelligence of Internal Auditors in Support of the Performance of Internal Audit Process - Study for Opinions of a Sample of Internal Auditors in Iraq
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Abstract

      The  aim of  the research to define the concept of moral intelligence and its dimensions and its relationship to some personal characteristics with the internal auditors and identify the importance of the employment of moral intelligence dimensions of (empathy, conscience, self- control, respect, kindness, tolerance, fairness) in the internal audit and the extent of support for the performance of the internal audit process in light of these dimensions. And that by answering the following question : Is there a role for moral intelligence  of  internal auditors in support the performance of internal audit process ? How are employ these dimensions i

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Publication Date
Sun Sep 01 2013
Journal Name
Journal Of Economics And Administrative Sciences
The Impact of Sharing knowledge on organizational innovation Field study in the arab company , for detergents and chemical
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ABSTRACT

Impkact  of  Knowledge  sharing  on  organizational  innovation  Impriscal  study in Arabic company . 

of  Knowledge Management is  the  main  component  Knowledge  sharing  system, it mean the exchange if  Knowledge, ideas, and good  practice with  another  individual . Knowledge sharing between persons, then its values can growth .

It is vry important because it can provide us with the contention between virus peoples . the interaction among the people can pass all kind of Knowledge among them. the connection and interaction and interaction enabl

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Publication Date
Tue Dec 31 2019
Journal Name
Journal Of Economics And Administrative Sciences
The Effect of Disclosure and Transparency Criteria In Saudi Banks on The Financial Ratios Indicators
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The study aimed to measure the effect of applying the disclosure and transparency standards criteria adopted by the Saudi Arabian Monetary Authority on improving performance indicators in the Saudi banking sector, by measuring the extent of the impact of the bank's financial indicators represented by liquidity, profitability and return on assets in Saudi banks by applying the criteria of disclosure and transparency, which is one of the Main principles in the list of governance, which was approved by the Saudi Arabian Monetary Authority. The analytical approach was followed to achieve the goal of the study, as the financial statements of Saudi banks were analyzed during a period of 8-year to test four hypotheses related to measuri

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Crossref
Publication Date
Tue Jan 29 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Financial contribution of taxes on Foreign oil companies in support of the state budget: The case of a foreign oil company in the Iraq Study
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Imposed on foreign oil companies from important sources in the financing of the general budget in most countries of the world income tax is considered as well as be used to achieve political, economic and social goals, and has developed the concept of the tax until it became play an important role in influencing the economic conditions of a country, and the aim of this research is to statement imposed on foreign oil companies operating in Iraq in the financing of the state budget income tax contribution, as well as clarify the contracts type contracts with these companies, which is in favor of Iraq, together with the Income Tax Law No. (19) for the year / 2010, and instructed No. (5) for the year / 2011, which organized the tax process s

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