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Finite Time Disturbance Observer Based on Air Conditioning System Control Scheme
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A novel robust finite time disturbance observer (RFTDO) based on an independent output-finite time composite control (FTCC) scheme is proposed for an air conditioning-system temperature and humidity regulation. The variable air volume (VAV) of the system is represented by two first-order mathematical models for the temperature and humidity dynamics. In the temperature loop dynamics, a RFTDO temperature (RFTDO-T) and an FTCC temperature (FTCC-T) are designed to estimate and reject the lumped disturbances of the temperature subsystem. In the humidity loop, a robust output of the FTCC humidity (FTCC-H) and RFTDO humidity (RFTDO-H) are also designed to estimate and reject the lumped disturbances of the humidity subsystem. Based on Lyapunov theory, the stability proof of the two closed-loop controllers and observers is presented. Comparative simulations are carried out to confirm that the proposed controller outperforms conventional methods and offers greater accuracy of temperature, humidity, and carbon dioxide concentration, having superior regulation performance in terms of a rapid finite time convergence, an outstanding disturbance rejection property, and better energy consumption. In addition to presenting the comparative simulation results from the control applications on the VAV system, the quantitative values are provided to further confirm the superiority of the proposed controller. In particular, the proposed method exhibits the shortest settling time of, respectively, 15 and 40 min to reach the expected temperature and humidity, whereas other comparative controllers require a longer time to settle down.

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Publication Date
Mon Feb 04 2019
Journal Name
Iraqi Journal Of Physics
Temperatture esttiimattiion off EXDRA and SSUMI dwarff Nova systtems from spectroscopic data
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The seasonal behavior of the light curve for selected star SS UMI and EXDRA during outburst cycle is studied. This behavior describes maximum temperature of outburst in dwarf nova. The raw data has been mathematically modeled by fitting Gaussian function based on the full width of the half maximum and the maximum value of the Gaussian. The results of this modeling describe the value of temperature of the dwarf novae star system leading to identify the type of elements that each dwarf nova consisted of.

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Publication Date
Tue Oct 02 2018
Journal Name
Iraqi Journal Of Physics
Gas sensitivity properties of TiO2/Ag nanocomposite films prepared by pulse laser deposition
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In this study, a double frequency Q-switching Nd:YAG laser beam (1064 nm and λ= 532 nm, repetition rate 6 Hz and the pulse duration 10ns) have been used, to deposit TiO2 pure and nanocomposites thin films with noble metal (Ag) at various concentration ratios of (0, 10, 20, 30, 40 and 50 wt.%) on glass and p-Si wafer (111) substrates using Pulse Laser Deposition (PLD) technique. Many growth parameters have been considered to specify the optimum condition, namely substrate temperature (300˚C), oxygen pressure (2.8×10-4 mbar), laser energy (700) mJ and the number of laser shots was 400 pulses with thickness of about 170 nm. The surface morphology of the thin films has been studied by using atomic force microscopes (AFM). The Root Mean Sq

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Publication Date
Sun Jun 01 2014
Journal Name
Baghdad Science Journal
Determination of total phenol, antioxidant and antimicrobial activities of Avena sativa and Ocimum basilicum
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The present study investigated the total content of phenolic compounds, antioxidant and antimicrobial activities of water extracts oat (Avena sativa) and basil (Ocimum basilicum), medicinal plants. The Folin-ciocalteu reagent assay was used to estimate the total phenolic content of plants extract. The antioxidant capacity of the plants extract was tested by ferric reducing/antioxidant power Assay (FRAP) and ferric reducing scavenging activity using DPPH method, and the antimicrobial activity was measured against [Staphylococcus epidermidis; Staphylococcus aureus; Proteus spp.; Klebsiella spp.; Escherichia coli; Candida albicans] as tester strains. The total phenolic content of Avena sativa and Ocimum basilicum extracts revealed that the

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Publication Date
Wed Feb 22 2023
Journal Name
Iraqi Journal Of Science
Facies, Depositional Environment and Cyclicity of the Fatha Formation in East Baghdad Oil Field, Iraq.
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This study deals with establishing the depositional environment of the Fatha Formation through facies analysis. It also deals with dividing the formation into units based on the rhythmic nature. Data from selected shallow wells near Hit area and deep wells at East Baghdad Oil field are used. Five major lithofacies are recognized in this study, namely, greenish grey marl, limestone, gypsum (and/or anhydrite), halite and reddish brown mudstone (with occasional sandstone).The limestone lithofacies is divided into three microfacies: Gastropods bioclastic wackestone microfacies, Gastropods peloidal bioclastic packstone, and Foraminiferal packstone microfacies.The lithofacies of the Fatha are nested in a rhythmic pattern or what is known as sh

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Publication Date
Sun Jan 04 2015
Journal Name
Journal Of Educational And Psychological Researches
The concept of physical, psychological and social self with the kindergartens
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The concept of self is considered one of the important dimensions in the human personality, because feeling of self is an important characteristic in this phase from the psychological point of view.

The first source which forms the concept of self is the physical image, where the built and appearance of the body is considered among the vital matters which determine the person's image of himself/herself. 

The current research aims to:

1) Identify the level of physical self concept at the kindergarten children.

2) Identify the level of psychological self concept at the kindergarten children.

3) Iden

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Engineering
DESIGN, CONSTRUCTION AND TESTING OF LOW SPEED WIND TUNNEL WITH ITS MEASUREMENT AND INSPECTION DEVICES
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A low speed open circuit wind tunnel has been designed, manufactured and constructed at the
Mechanical Engineering Department at Baghdad University - College of Engineering. The work is one of
the pioneer projects adapted by the R & D Office at the Iraqi MOHESR. The present paper describes the
first part of the work; that is the design calculations, simulation and construction. It will be followed by a
second part that describes testing and calibration of the tunnel. The proposed wind tunnel has a test
section with cross sectional area of (0.7 x 0.7 m2) and length of (1.5 m). The maximum speed is about (70
m/s) with empty test section. The contraction ratio is (8.16). Three screens are used to minimize flow
distu

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Publication Date
Fri Jul 01 2022
Journal Name
Journal Of Engineering
An Applying the Delphi Technique for Eliciting Criteria in Equipment and Materials Used in Highway Construction Projects
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This article aims to establish and evaluate standards for critical equipment and materials in highway projects in Iraq. Delphi technique has been used to analyze, explore, and discover the main criteria and sub-criteria that affect equipment and materials in highway construction projects in Iraq. To determine the correct response to the criteria presented in this study, a program (IBM, SPSS/V25) was used to assess the main criteria and sub-criteria using the mean score (MS) and standard deviation (SD) technique, as well as to check reliability using Cronbach's alpha factor (α). The experts' qualifications and the extent to which the person is ready to commit are both important factors in panel selection. The design of a

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Publication Date
Sun Nov 01 2020
Journal Name
The Iraqi Journal For Information And Documentation Studies
Smart Libraries and Their Applications in The Arab World
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The main aim of conducting this research is to identify the applications of Smart libraries in the Arab world. The Researcher relied on the documentary and Survey approach to collect information and data through the Internet, and to get to know these libraries. Then the Research came in three sections dealing with the first topic: The general framework of the study. The second topic deals with: introducing Smart libraries and indicating their types and characteristics. The Third topic dealt with the requirements of Smart libraries'application by identifying the basic components of it (Smart building, Smart Librarian , Smart devices, systems and software, Smart information sources,and Smart beneficiaries), and dealt with Smart libraries appl

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Publication Date
Sun Sep 01 2013
Journal Name
Baghdad Science Journal
Comparison study of Interleukin-1 alpha between Unstable Angina and Acute Myocardial Infarction patients
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Multiple studies support a role for inflammation in the pathogenesis of coronary atherosclerosis and unstable cardiac syndromes. However, of the known pro-inflammatory cytokines, only elevated plasma levels of interleukin-6(IL-6) have been linked to Unstable Angina. We sought to examine the plasma levels of other major proinflammatory cytokines in similar clinical settings patients with unstable angina and acute myocardial infarction and the relationship extent between them. This study aimed to investigate and compare the level of IL-1 in Unstable Angina and Acute Myocardial Infarction patients. Thirty patients with unstable angina and thirty patients with Acute Myocardial Infarction, also thirty healthy individual as control were included

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Publication Date
Tue Aug 03 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Using financial and non-financial information ) SASB standards) to enhance investor confidence
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Companies seek to enhance investor confidence by achieving the highest level of transparency in disclosure of financial and non-financial information (SASB standards) for Iraqi insurance companies listed on the financial market. The aim of the research is to identify the extent of the ability of financial and non-financial information to enhance transparency in reporting, which is reflected in Investor confidence. And the standards of sustainability development accounting issued by (SASB) through the electronic questionnaire that was distributed. Companies seek to achieve a set of goals, the most important of which is to enhance investor confidence by improving transparency in disclosure. Concerning the employment of financial an

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