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Mathematical Statistics - Second Edition
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This Book is the second edition that intended to be textbook studied for undergraduate/ postgraduate course in mathematical statistics. In order to achieve the goals of the book, it is divided into the following chapters. Chapter One introduces events and probability review. Chapter Two devotes to random variables in their two types: discrete and continuous with definitions of probability mass function, probability density function and cumulative distribution function as well. Chapter Three discusses mathematical expectation with its special types such as: moments, moment generating function and other related topics. Chapter Four deals with some special discrete distributions: (Discrete Uniform, Bernoulli, Binomial, Poisson, Geometric, Negative Binomial and Hypergeometric) with their mathematical formulas of p.m.f., C.D.F. and m.g.f. Chapter Five deals with some special continuous distributions: (Uniform, Normal, Exponential, Gamma and Beta) with their mathematical formulas of p.m.f., C.D.F. and m.g.f. Many solved examples are intended in this book (obtaining mean and variance of distributions by m.g.f.). Chapter Six introduces univariate discrete and continuous transformations, i.e., one dimensional variables and their yielding probability distributions. Chapter Seven devotes to truncation of distributions from left, right or both sides, beside the probability distribution of order statistics. Chapter Eight discusses mathematical features of joint, marginal and conditional distributions, as well as independency via covariance and correlation of bivariate distributions. Chapter Nine deals with some special topics such as getting distribution for some transformation from multidimensional random variables by using moment generating function (m.g.f.) and cumulative distribution function (C.D.F.) Many solved examples (about 100) are intended in this book, in addition to a variety of unsolved relied problems (about 150) at the end of each chapter to enrich the statistical knowledge of our readers.

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Publication Date
Tue Jan 11 2022
Journal Name
Iraqi Journal Of Science
Methods and Simulations used to Detect Photons from Exoplanets of a Parent Star
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The extrasolar planets in the vicinity of stars are expected to be bright enough
and are very difficult to be observed by direct detection. The problem is attributed to
the side loops of the star that created due to the telescope diffraction processing.
Several methods have been suggested in the literatures are being capable to detect
exoplanet at a separation angle of 4λ/D and at a contrast ratio of 10-10. These
methods are more than one parameter function and imposing limitations on the inner
working distance. New simple method based on a circular aperture combined with a
third power Gaussian function is suggested. The parameters of this function are then
optimized based on obtaining a minimum inner working dis

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Publication Date
Wed Dec 30 2020
Journal Name
Iraqi Journal Of Science
Adopting Image Integration Techniques to Simulate Satellite Images
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Mathematical integration techniques rely on mathematical relationships such as addition, subtraction, division, and subtraction to merge images with different resolutions to achieve the best effect of the merger. In this study, a simulation is adopted to correct the geometric and radiometric distortion of satellite images based on mathematical integration techniques, including Brovey Transform (BT), Color Normalization Transform (CNT), and Multiplicative Model (MM). Also, interpolation methods, namely the nearest neighborhood, Bi-linear, and Bi-cubic were adapted to the images captured by an optical camera. The evaluation of images resulting from the integration process was performed using several types of measures; the first type depend

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Publication Date
Fri Dec 01 2017
Journal Name
International Journal Of Science And Research
Theoretical and Experimental Study of Nanofiltration and Reverse Osmosis Membranes for Removal of Heavy Metals from Wastewater
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The present work aimed to study the efficiency of nanofiltration (NF) and reverse osmosis (RO) membrane for heavy metal removal from wastewater and study the factors affecting the performance of these two membranes: feed concentrations for heavy metal ions, pressure, and flow rate. The experimental results showed, heavy metals concentration in permeate increase with raise in feed concentrations, decline with increase in flow rate. The raise of pressure, heavy metals concentration decreases for RO membrane, but for NF membrane the concentration decrease and then at high pressure increase. The rejection percentage for chromium in NF and RO is 99.7% and 99.9%, for copper is 98.4% and 99.3%, for zinc is 97.9% and 99.5%, for nickel is 97.2% and

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Publication Date
Mon Dec 18 2017
Journal Name
Al-khwarizmi Engineering Journal
Experimental and Numerical Study of Collector Geometry Effect on Solar Chimney Performance
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There have been many advances in the solar chimney power plant  since 1930 and the first pilot work was built in Spain (Manzanares) that produced 50 KW. The solar chimney power plant is considered of a clean power generation that needs to be investigated  to enhance the performance by studying the effect of changing the area of passage of air to enhance the velocity towards the chimney to maximize design velocity. In this experimental and numerical study, the reduction area of solar collector was investigated. The reduction area that mean changing the height of glass cover from the absorbing plate (h1=3.8cm, h2=2.6cm and h3=1.28cm). The numerical study was performed using ANSYS Fluent software package (version 14.0) to solve go

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Publication Date
Fri Oct 20 2023
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Building an Analytical Method to Study Cantilever Beam Dynamic Response
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Cantilever beams are used in many crucial applications in machinery and construction. For example, the airplane wing, the microscopic probe for atomic force measurement, the tower crane overhang and twin overhang folding bridge are typical examples of cantilever beams. The current research aims to develop an analytical solution for the free vibration problem of cantilever beams. The dynamic response of AISI 304 beam represented by the natural frequencies was determined under different working surrounding temperatures ((-100 ℃ to 400 ℃)). A Matlab code was developed to achieve the analytical solution results, considering the effect of some beam geometrical dimensions. The developed analytical solution has been verified successfully wi

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Publication Date
Sun Dec 01 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Faithful representation of accounting information according requirements width financial statements depending on international standard (IFRS-15) revenue from contracts with customers: Applied research in a sample of the joint stock companies listed on the Iraq Stock Exchange
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This study seeks to identify the possibility of achieving the property of faithful representation of accounting information and measure it by using the standard approach based on mathematical and statistical equations by comparing two financial periods before and after the application of (IFRS-15) Revenue from contracts with customers, during the period. (2014-2018), for the financial statements of the mixed joint stock companies listed on the Iraq Stock Exchange, which is one of the main pillars of the economic structure of the country, as a joint investment between the state and the private sector, and has importance in many aspects, including support for projects of public companies, S Absorption and employment of labor, as well as ra

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Publication Date
Fri Mar 27 2020
Journal Name
Iraqi Journal Of Science
Impact of Geological Structures on Rock Slope Stability in The NW Nose (Plunge ) of Surdash Anticline, Sulaimaniya/ NE Iraq
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The road network in Surdash anticline is considered as an important road network connecting lower Dukan town with the touristic upper Dukan town. Dukan lake plays an important role in the social and economic activities of Dukan town and the surrounding areas.
For assessing the stability of the rock slopes in the area, 9 stations were selected along the upper Dukan road on both sides of Surdash anticline, and their stability was evaluated by the kinematic analysis using DIPS V6.008 software. 
Kinematic analysis of the studied stations shows thatplanar sliding is possible in stations No. 1, 2, 3 and 8, while wedge sliding is possible in station No. 5, 6, 7 and 9b. The other stations (No. 4and 9a) are stable. Tectonic structures

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Publication Date
Tue Aug 03 2021
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
The role of coordination and joint cooperation in raising the quality of auditing in accordance with the INTOSAI standard(9150 (: Applied research in the General Company for Marketing Medicines and Medical Appliances - Kimadia
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The process of coordination and joint cooperation between SAIs and internal auditors in the public sector is considered one of the very important matters in performing efficient audits and are of high quality, especially if this coordination and cooperation is implemented in accordance with international standards, as it leads to avoiding duplication in auditing work. And the distribution of work in a distribution that achieves the objectives of auditing in general and is of general benefit to the economic unit.

The research problem lies in the weakness of the relationship between internal auditing and external auditing as a result of not applying INTOSAI Standard (9150) coordination and joint cooperation

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Publication Date
Fri Jun 30 2017
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Improving of Design Parameters of an Industrial Continuous Catalytic Reforming Reactors
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Catalytic reforming of naphtha occupies an important issue in refineries for obtaining high octane gasoline and aromatic compounds, which are the basic materials of petrochemical industries. In this study, a novel of design parameters for industrial continuous catalytic reforming reactors of naphtha is proposed to increase the aromatics and hydrogen productions. Improving a rigorous mathematical model for industrial catalytic reactors of naphtha is studied here based on industrial data applying a new kinetic and deactivation model. The optimal design variables are obtained utilizing the optimization process in order to build the model with high accuracy and such design parameters are then applied to get the best configuration of this pro

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Publication Date
Thu Oct 20 2022
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Theoretical Investigations of High Power Yb3+: YAG Thin-Disk Laser
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     The present study includes a theoretical treatment to derive the general equations of pumping threshold power ( ), laser output power (Pout), and laser device efficiency (ƞ) of the element-doped thin-disk laser (Yb3+) with a quasi-three-level pumping scheme in the continuous wave mode at a temperature of (299K°). In this study, the host crystals (YAG) were selected as typical examples of this laser design in a Gaussian transverse mode. The numerical solution of these equations was made using Matlab software by selecting the basic parameters from the recently published scientific articles for the laser design of these crystal hosts. According to this simulation, this article studied the effect o

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