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OPEN CIRCUIT HEAT EXCHANGER DYNAMICS DURING FLOW REDUCTION TRANSIENT IN THEIR SECONDARY LOOPS
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An experimental and theoretical analysis was conducted for simulation of open circuit cross flow heat
exchanger dynamics during flow reduction transient in their secondary loops. Finite difference
mathematical model was prepared to cover the heat transfer mechanism between the hot water in the
primary circuit and the cold water in the secondary circuit during transient course. This model takes under
consideration the effect of water heat up in the secondary circuit due to step reduction of its flow on the
physical and thermal properties linked to the parameters that are used for calculation of heat transfer
coefficients on both sides of their tubes. Computer program was prepared for calculation purposes which
cover all the variables that affect such type of transient mechanisms. The effect of the power density in
the primary circuit and the water flow reduction percentage on the average temperature build up of the
water in the primary circuit was investigated. The elapsed time required for the primary circuit average
temperature to reach a steady state value was also calculated. These calculations were supported with
experimental measurements conducted on a standard cross flow heat exchanger apparatus. The
experimental results were compared with the theoretical results for certain power density value at
different flow reduction percentages which show a reliable agreement. This relative agreement was
necessary to consider the mathematical model with certain assurance for calculating transient parameters
for higher power densities that are out of apparatus ranges. The results proved that water average
temperature build up in the primary circuit has sharp tendency when the percentage of flow reduction in
the secondary circuit reach 25% of its nominal values.

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Smart Thinking at Secondary Schools' Students
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Present research is aimed knowing of smart thinking for secondary schools' students. and discover statistically significant differences in Smart Thinking due to the couple variables of (Gender – Branch)
For the purpose of verification of the aims of the research, the researcher has prepared a smart thinking scale, the scale has been applied on sample of secondary schools' students for both Branches (Scientific & Literary One).It was contingent (500) student male and female were chosen stratified random method.
After data analyze the reached results: The Preparatory fourth grade students have smart thinking. Female smart thinking enjoy a much higher degree than males. and Scientific branch students enjoy thinking and much high

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Publication Date
Mon Feb 04 2019
Journal Name
Journal Of The College Of Education For Women
Moral anxiety among secondary school students
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Research targeted availability of moral anxiety among secondary school students. The research sample consisted of 500 students from the (fifth grade secondary school) scientific and literary branches.
The researcher prepared a measure of moral anxiety which is in its final form of (36) items. The researcher analyzed the data statistically, significant results showed that the sample of the research they have a moral anxiety .
From these results the researcher came up with a number of recommendations and proposals.

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Publication Date
Wed May 01 2019
Journal Name
Journal Of Engineering
Reduced Complexity SLM Method for PAPR Reduction
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In this paper, the computational complexity will be reduced using a revised version of the selected mapping (SLM) algorithm. Where a partial SLM is achieved to reduce the mathematical operations around 50%. Although the peak to average power ratio (PAPR) reduction gain has been slightly degraded, the dramatic reduction in the computational complexity is an outshining achievement. Matlab simulation is used to evaluate the results, where the PAPR result shows the capability of the proposed method.  

 

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Publication Date
Wed Jan 15 2020
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The responsibility of the administration in compliance with the going concern assumption during the preparation for their financial statements: Research practically at muster of companies
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This research aims to demonstrate the impact of the going concern assumption in different accounting applications to provide a realistic look and more accurate result of activity and financial situation, as well as determining the responsibility of the Company's administration in compliance with the going concern assumption during the preparation for their financial statements, and to clarify the concept of integration between internal audit and external audit about going concern assumption, besides its importance and usefulness on the work of both of the internal auditor and the external auditor, as well as on the company under auditing process.This research purports preparing an internal audit program, including a set of auditing actio

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Publication Date
Sat Mar 30 2013
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Theoretical Study on Heat Transfer in the Presence of Fouling
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The fouling depositions of crude oil stream were studied theoretically in a shell and tube heat exchanger to investigate the effect of depositions on the heat transfer process. The employed heat exchanger was with steam flowing in the inner tubes and crude oil in the shell at different velocities and bulk temperatures. It is assumed that fouling occurs only on the heated stream side (crude oil). The analysis was carried out for turbulent flow heat transfer conditions with wide range of Reynolds number, bulk temperature and time. Many previously proposed models for fouling resistance were employed to estimate a new model for fouling rate. It is found that the fouling rate and consequently the heat transfer coefficient were affected by Rey

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Publication Date
Thu Jul 01 2021
Journal Name
Journal Of Mechanical Engineering Research And Developments
Numerical Investigation of Natural Convection Heat Transfer in Partially Filled Porous Enclosure Subjected to Constant Heat
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Steady natural convection in a square enclosure with wall length (L= 20 cm) partially filled by saturated porous medium with same fluid (lower layer) and air (upper layer) is investigated. The conceptual study of the achievements of the heat transfer is performed under effects of bottom heating by constant heat flux (q=150,300,450,600W/m2 ) for three heaters size (0.2,0.14,0.07)m with symmetrically cooling with constant temperature on two vertical walls and adiabatic top wall. The relevant filled studied parameters are four different porous medium heights (Hp=0.25L,0.5L, 0.75L, L), Darcey number (Da1) 3.025×10-8 and (Da2) 8.852×10-4 ) and Rayleigh number range (60.354 - 241.41), (1.304×106 – 5.2166×106 ) for Da1 and Da2 cases respecti

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Publication Date
Thu Nov 08 2018
Journal Name
Iraqi National Journal Of Nursing Specialties
Obesity and Overweight among Students in Arabic Secondary Schools in Erbil City
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Objective(s): The aim of the study was to identify the prevalence of overweight and obesity in adolescence and
to estimate the effect of socio- demographic and health behaviors that predicting obesity in adolescents.
Methodology: A cross-sectional descriptive study was being carried out at three public Arabic secondary
schools in Erbil city from October 1
st 2010 to January 30th 2011. A systematic randomly sample size of 461 students
was selected.
Results: In this study, the age of (46.2%, 122) of males students were ranged between (17- 18.9) years old compared
to females students (74.1%, 146) their age ranged between (15 -16.9) years old. About (3.4%, 9) of males
adolescents having overweight while all female ado

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Publication Date
Mon Jan 01 2024
Journal Name
Communications In Mathematical Biology And Neuroscience
Effects of fear and refuge strategy dependent on predator in food web dynamics
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Publication Date
Tue Jan 23 2024
Journal Name
Journal Of Applied Mathematics
Dynamics Analysis of a Delayed Crimean-Congo Hemorrhagic Fever Virus Model in Humans
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Given that the Crimean and Congo hemorrhagic fever is one of the deadly viral diseases that occur seasonally due to the activity of the carrier “tick,” studying and developing a mathematical model simulating this illness are crucial. Due to the delay in the disease’s incubation time in the sick individual, the paper involved the development of a mathematical model modeling the transmission of the disease from the carrier to humans and its spread among them. The major objective is to comprehend the dynamics of illness transmission so that it may be controlled, as well as how time delay affects this. The discussion of every one of the solution’s qualitative attributes is included. According to the established basic reproductio

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Publication Date
Thu Jan 30 2020
Journal Name
Al-kindy College Medical Journal
Conversion Rate from Laparoscopic to open Cholecystectomy in AL-kindy Teaching Hospital, Baghdad
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Background: laparoscopic cholecystectomy (LC) is getting popularity for the treating of symptomatic gall bladder disease; conversion from laparoscopic to open cholecystectomy (OC) is also common.

Objective : To find out the prevalence of causes, risk factors of conversion from LC to OC among  patient suffering from gall bladder disease, and  to explore the most common causes of conversion from laparoscopic to open cholecystectomy.

Methods: This prospective study was conducted in the department of general surgery at Alkindy teaching hospital from first of January 2016 to the end of December 2017 .Nine hundred twenty patient were included. Patient age, gender, his

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