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Optimal insulation design of form-wound stator winding with stress grading system under fast rise-time excitation
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The effective insulation design of the stress grading (SG) system in form-wound stator coils is essential for preventing partial discharges and excessive heat generation under pulse-width modulation excitation. This paper proposes a method to find the optimal insulation design of the SG system aimed at reducing the dielectric and thermal stresses in the machine coil. The non-uniform transmission line model is used to predict the voltage propagation along the overhang, SG, and slot regions considering the variation in the physical properties of the insulation layers. The machine coil parameters for different insulation materials are calculated by using the finite element method. Two optimization algorithms, fmincon and particle swarm optimization (PSO), are applied and compared to find the optimal thickness and material properties of each insulation layer as well as the length and location of the SG system. The results under different rise-time excitation show that the optimized geometry by using PSO can produce a higher reduction in the dielectric and thermal stresses, as well as in the maximum overvoltage along the machine coil than the original geometry and the optimized geometry using fmincon. The machine coil model is validated by means of comparisons with experimental measurements.

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Publication Date
Mon Jul 20 2020
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
The Continuous Classical Boundary Optimal Control Vector Governing by Triple Linear Partial Differential Equations of Parabolic Type
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In this paper, the continuous classical boundary optimal control problem (CCBOCP) for triple linear partial differential equations of parabolic type (TLPDEPAR) with initial and boundary conditions (ICs & BCs) is studied. The Galerkin method (GM) is used to prove the existence and uniqueness theorem of the state vector solution (SVS) for given continuous classical boundary control vector (CCBCV). The proof of the existence theorem of a continuous classical boundary optimal control vector (CCBOCV) associated with the TLPDEPAR is proved. The derivation of the Fréchet derivative (FrD) for the cost function (CoF) is obtained. At the end, the theorem of the necessary conditions for optimality (NCsThOP) of this problem is stated and prov

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
The technique of converting multi-choice mathematical programming into linear mathematical programming to find the optimal solution
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The study deals with the issue of multi-choice linear mathematical programming. The right side of the constraints will be multi-choice. However, the issue of multi-purpose mathematical programming can not be solved directly through linear or nonlinear techniques. The idea is to transform this matter into a normal linear problem and solve it In this research, a simple technique is introduced that enables us to deal with this issue as regular linear programming. The idea is to introduce a number of binary variables And its use to create a linear combination gives one parameter was used multiple. As well as the options of linear programming model to maximize profits to the General Company for Plastic Industries product irrigation sy

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Crossref
Publication Date
Fri Apr 30 2021
Journal Name
Iraqi Journal Of Science
Determination of the Annual Optimal Reliable Frequency for Different Transmitter/Receiver Stations Distributed over the Iraqi Territory
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This paper aimed to determine the Optimal Reliable Frequency (ORF) that can maintain certain connection link between different transmitter/receiver stations laid over the Iraqi territory. Three different transmitting sites were chosen as tested stations located in the northern, central, and southern regions of Iraq. These sites are Mosul, Baghdad, and Basra, respectively. In this study, the years 2009 and 2014, which represent the minimum and maximum years of solar cycle 24, were chosen to examine the effect of low and high solar activity on the determined ORF. The datasets of the Best Usable Frequency (BUF) were calculated using the ASAPS international communication model. An analytical study was made on the generated BUF parameter data

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Publication Date
Wed May 03 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Identify The Optimal Values of the Geometric Deformable Models Parameters to Segment Multiple objects in Digital Images
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 Accuracy in multiple objects segmentation using geometric deformable models sometimes is not achieved for reasons relating to a number of parameters. In this research, we will study the effect of changing the parameters values on the work of the geometric deformable model and define their efficient values, as well as finding out the relations that link these parameters with each other, by depending on different case studies including multiple objects different in spacing, colors, and illumination. For specific ranges of parameters values the segmentation results are found good, where the success of the work of geometric deformable models has been limited within certain limits to the values of these parameters.

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Publication Date
Wed Jan 22 2020
Journal Name
Iraqi Journal Of Laser
Stress Urinary Incontinence Treatment Using Vaginal Fractional CO2 Laser (10600nm)
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Stress urinary incontinence (SUI) is involuntary urine leakage during activities that increase abdominal pressure such as coughing, sneezing and lifting of heavy weights. This is a very common disorder among women with history of multiple vaginal deliveries with an obstructed labor. SUI is considered one of the most distressing problems, especially for younger women, with severe quality of life implications, it caused by the loss of urethral support, usually as a consequence of the supporting structural muscles in the pelvis.

Objective: To prove and demonstrate the effect of a fractional CO2 micro-ablative laser (10600nm) in intra vaginal therapy for treating SUI and achieve a clinical improvement of t

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Publication Date
Mon Dec 20 2021
Journal Name
Baghdad Science Journal
Temperature Stress on Physiological and Morphological Traits in Rhizophora apiculata
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Global warming has had considerable effects on vital ecosystems, which has also been caused by increased temperatures and CO2 that follow changes in different abiotic factors, which poses threats to mangrove forests environment. This research was conducted to examine the physiological and morphological characteristics of the Rhizophora apiculata mangrove regarding higher air temperature for the variety of tree species that respond to climate change. Seedlings were cultivated for three months in regulated growth chambers with three varying temperatures of 38°C, 21°C under CO2 at 450 ppm, and ambient CO2 concentration i.e., 450 ± 20 ppm under average temperature at 28°C as the control condition

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Publication Date
Mon Mar 28 2022
Journal Name
The Open Dentistry Journal
Depression, Anxiety and Stress Among Dentists During COVID-19 Lockdown
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Introduction:

The objective of this study was to investigate the levels of depression, anxiety, and stress among dentists during covid-19 lockdown and to investigate the relationship between stress and each mental health state.

Methods:

A cross-sectional survey on 269 dentists was conducted using DASS-21 and PHQ-9 questionnaires. Bivariate and multivariate models were constructed and the odds ratio (OR) was calculated to assess the strength of the association between an independent categorical variable and the outcome.

Results and Discussion:

Being unsatisfied with the job was as

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
Numerical Approximations of a One-Dimensional Time-Fractional Semilinear Parabolic Equation
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     The time fractional order differential equations are fundamental tools that are used for modeling neuronal dynamics. These equations are obtained by substituting the time derivative of order  where , in the standard equation with the Caputo fractional formula. In this paper, two implicit difference schemes: the linearly Euler implicit and the Crank-Nicolson (CN) finite difference schemes, are employed in solving a one-dimensional time-fractional semilinear equation with Dirichlet boundary conditions. Moreover, the consistency, stability and convergence of the proposed schemes are investigated. We prove that the IEM is unconditionally stable, while CNM is conditionally stable. Furthermore, a comparative study between these two s

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Publication Date
Sat Sep 23 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Real-time control for the transmission of information in wireless networks
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Wireless  lietworking is·  constantly improving,  changing  and

though  ba ic  principle  is the same.  ['nstead of  using standard  cables  to transmit information fmm one point to another (qr more), it .uses  radio signals.  This paper  presents .a case  study considedng real-time remote

cqntroJ using Wireless UDP/JP-based networks,. The aim of-this werk is to

reduce  real-time· remote control  system  based upon a simulatio.n  model,

which can operate via general communication  l"]etworks, whieh on bodies. modern wireles  tcchnolqgy.

The  first  part includes· a  brief

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Publication Date
Thu Apr 14 2022
Journal Name
Plos One
The passage of time in Iraq during the covid-19 pandemic
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The covid-19 global pandemic has influenced the day-to-day lives of people across the world. One consequence of this has been significant distortion to the subjective speed at which people feel like time is passing. To date, temporal distortions during covid-19 have mainly been studied in Europe. The current study therefore sought to explore experiences of the passage of time in Iraq. An online questionnaire was used to explore the passage of time during the day, week and the 11 months since the first period of covid-19 restrictions were imposed in Iraq. The questionnaire also measured affective and demographic factors, and task-load. The results showed that distortions to the passage of time were widespread in Iraq. Participants co

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