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Optimal Dielectric Design of Medium Voltage Toroidal Transformer with Electrostatic Shield under Fast Front Excitation
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Accurate calculation of transient overvoltages and dielectric stresses from fast-front excitations is required to obtain an optimal dielectric design of power components subjected to these conditions, which are commonly due to switching and lightning, as well as utilization of power-electronic devices. Toroidal transformers are generally used at the low voltage level. However, recent investigations and developments have explored their use at the medium voltage level. This paper analyzes the model-based improvement of the insulation design of medium voltage toroidal transformers. Lumped and distributed parameter models are used and compared to predict the transient response and dielectric stress along the transformer winding. The parameters of the toroidal transformer are computed using the finite element method considering a three-dimensional geometry. Different strategies for insulation design are proposed by means of optimal insulation thickness and electrostatic shield to reduce transient overvoltage and dielectric stress. The results show that the proposed optimal insulation design based on particle swarm optimization with electrostatic shield can substantially reduce the dielectric stress and dielectric distances. Comparison between simulations and experimental results demonstrates that the frequency domain modeling approach results in accurate calculation of transient overvoltages produced by fast front excitation and can be used effectively for insulation design.

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Publication Date
Tue Jun 01 2021
Journal Name
Journal Of Engineering
Numerical Study for HAWT Wake shape with different Angles of Attack
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Increasing world demand for renewable energy resources as wind energy was one of the goals behind research optimization of energy production from wind farms. Wake is one of the important phenomena in this field. This paper focuses on understanding the effect of angle of attack (α) on wake characteristics behind single horizontal axis wind turbines (HAWT). This was done by design three rotors different from each other in value of α used in the rotor design process. Values of α were (4.8˚,9.5˚,19˚). The numerical simulations were conducted using Ansys Workbench 19- Fluent code; the used turbulence model was (k-ω SST). The results showed that best value for extracted wind energy was at α=19˚, spread distance of wak

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Publication Date
Fri Jan 01 2016
Journal Name
Journal Of Engineering
Theoretical and Experimental Stress Analysis of Cam With Simple Harmonic Motion
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Cams are considered as one of the most important mechanical components that depends the contact action to do its job and suffer a lot of with drawbacks to be predicted and overcame in the design process. this work aims to investigate the induced cam contact and the maximum shear stress energy or (von misses) stresses during the course of action analytically using Hertz contact stress equation and the principal stress formulations to find the maximum stress value and its position beneath the contacting surfaces. The experimental investigation adopted two dimensions photoelastic technique to analyze cam stresses under a plane polarized light. The problem has been numerically simulated using Ansys software version 15 as FE

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Publication Date
Sun Oct 29 2023
Journal Name
Iraqi National Journal Of Nursing Specialties
Impact of Chemotherapy upon Lifestyle for the Patient with BIadder Cancer
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Objectives: The study aimed to determine the effect of chemotherapy on the life style of patients who
receive chemotherapy.
Methodology: A descriptive study was conducted in Specialty Surgery Teaching Hospital, Al-yamok
Teaching Hospital, and Radiation and Nuclear Medicine Hospital in Baghdad for the period from May
2007 to October 2008. A purposive "non-probability" sample of (loo) patients with bladder cancer
who receive chemotherapy where concerned in this study.
A questionnaire fom was constnicted for the purpose of the study and it was comprised of
two parts. The questiormaire consists of (125) items. They include (1) demographic information (2)
assessment of lifestyle dimension. The content validity of the q

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Publication Date
Wed Oct 31 2018
Journal Name
Al-kindy College Medical Journal
Leigh Syndrome: Report of a Rare Case with Late Onset Presentation
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Leigh's syndrome, or sub acute necrotizing encephalomyelopathy, is a rare inherited neurometabolic disease of infancy and early childhood with variable course and prognosis. Rarely, it occurs in juveniles and adults. The diagnosis is difficult and still remains to challenge the clinicians on the basis of history; hence the role of imaging is very essential. It is the neuroimaging, chiefly the Magnetic Resonance Imaging showing characteristic symmetrical necrotic lesions in the basal ganglia and/or brain stem that leads to the diagnosis. Late-onset varieties are rare and only few cases were reported all over the world. Here, I report a case of late onset (juvenile) Leigh syndrome presenting with an acute polyneuropathy. Neuroimaging confi

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Crossref
Publication Date
Mon Dec 25 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Spectrophotometric Determination of Cefixime Following Simple Diazotization and Coupling with ?-Naphthol
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Cefixime (CFX) was treated with sodium nitrite and hydrochloric acid for diazotization reaction followed by coupling with ?-Naphthol in alkaline medium to form, a yellow colored azo dye compound which exhibits maximum absorption (?max) at 412 nm where the concentration of (CFX) was determined spectrophotometrically. The optimum reaction conditions and other analytical parameters were evaluated. Beer’s law was obeyed in the concentration range of (1-20) ?g.mL-1 with a molar absorptivity of 34870.5 L.mol-1.cm-1. The limit of detection was found to be 0.1090 ?g.mL-1 and the Sandell's sensitivity value was 0.0130 ?g.cm-2. The proposed method could be successfully applied to

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Crossref
Publication Date
Thu Jan 30 2014
Journal Name
Al-kindy College Medical Journal
Microbiology of active chronic otitis media: in comparison with abroad studies
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Background: Chronic otitis media (COM) of mucosal or squamous type is a common problem in otolaryngology practice, the active form of COM is characterized by discharge of pus and is treated by antibiotics to start with, the appropriate antibiotic should be prescribed to avoid antibiotic abuse and guarantee good outcome. Objectives:The objective of this study is to identify the causative organisms of active chronic active otitis media both (mucosal, squamous) type and test their sensitivity to various anti- microbial agents &compare with abroad studies.Methods:A prospective study was done on eighty patients, different ages and sexes were taken and carful history and examination was done, examination under microscope was done with carf

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Publication Date
Thu Apr 18 2019
Journal Name
Al-kindy College Medical Journal
The state of Vitamin D in Iraqi Patients With Parkinson Disease
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Background: A role for vitamin D deficiency in Parkinson disease (PD) has recently been suggested.

Objective:: To estimate the state of vitamin D in PD with an age-matched healthy control.

Type of the study: A case control study.

Method: The study randomly comparison of plasma 25-hydroxyvitamin D (25[OH] D) concentrations of collected samples in a clinical neurology department ward / Baghdad teaching hospital / Medical City and Parkinson disease movement disorder clinic. Participants were registered into the study from October 2015 to October 2016. We was study   serum vitamin D level in 40 consecutive patients with

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Publication Date
Mon May 22 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Using of Some Bacterial Species to Treat Polluted Soils with Hydrocarbons.
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    Three bacterial species were isolated from three polluted soils with gasoline which leaks from electricity generators that used in different regions in Baghdad; the regions choices to collect the polluted soils were (Al-Shaab, Al- Jadryia and Al-Saydiya).     The bacterial species were identified according to international biochemical   methods. It was found that these species were Escherichia coli, Enterobacter    aerogenes and serratia marcesens.      It was found that the optimum temperature and pH were 37C°and 9 these were to cultivate E.coli and S.marcesens, while for   E.aerogenes   were 25 C° and   9. &

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Publication Date
Mon Jun 05 2023
Journal Name
Journal Of Engineering
Compressive Behavior of Fiber Reinforced Concrete Columns Rehabilitated with CFRP Warps
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Over the last few years, there has been a worldwide increase in the use of composite materials for rehabilitation of deficient reinforced concrete structures. One important application of this technology is the use of Carbon Fiber Reinforced Polymer (CFRP) jacket to provide external confinement of reinforced concrete columns. Square concrete column specimens 100×100×1000 mm with concrete
compressive strength of about 30 and 50 MPa, steel fiber volume fraction 0%, 0.5%, 0.75%, and percentage of longitudinal reinforcement 2.01%, 3.14% and 4.52% were tested until failure in previous research. In this research seven tested columns were repaired and rehabilitated using one layer of CFRP flexible wraps and tested to determine their ultim

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Crossref
Publication Date
Fri Jul 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study of Some Biochemical Parameters in Iraqi Male Children with Thalassemia
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Thalassemia is a term that refers to a group of genetic disorders characterized by a defect in the synthesis of hemoglobin. It is sometimes called Mediterranean anemia. Many biochemical changes in the blood accompany this disease. In this research, some biochemical parameters were measured in thalassemic patients and compared with healthy control group. These parameters include serum Iron, ferritin, TIBC, hemoglobin, uric acid, albumin, calcium, transferrin, and transferrin saturation percentage.  The results of the research showed that there is a significant increase (P<0.05)  in serum iron and ferritin in thalassemic patients group in comparison with healthy control group. A significant decrease (P<0.05) in serum uric a

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