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Publication Date

Mon Oct 01 2012

Journal Name

Iraqi Journal Of Physics

Volume

10

Issue Number

18

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Sttudy tthe oriienttattiion and diisttance ffacttors effffectts on tthe llower usablle ffrequency ((LUF)) over miiddlle eastt regiion

Radio Wave Propagation

LUF

Lowest Usable Frequency

HF-Models

Khalid A.

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In this research, the influence of the orientation and distance factors on the lowest usable frequency (LUF) parameter has been studied theoretically. The calculations of the (LUF) parameter have been made using the (VOACAP) international communication model for the connection links between the capital Baghdad and many other locations that distributed on different distances and directions over the Middle East region. The results shown in this study indicate there is a slight affection of the link direction (orientation) on the LUF parameter, while the influence of the distance factor is more significant on the values of the LUF parameter. The day/night effect appears for the long distance HF links (i.e. more than a 500 Km)

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Publication Date

Mon Jan 13 2020

Journal Name

Day 3 Wed, January 15, 2020

Numerical Simulation of Gas Lift Optimization Using Genetic Algorithm for a Middle East Oil Field: Feasibility Study

Constrained optimization

Gas lifts

Gases

Gasoline

Genetic algorithms

Life cycle

Natural gas fields

Numerical models

Offshore oil well production

Oil fields

Mustafa

Mofazzal

Omar

Akim

Abbas

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<p>Gas-lift technique plays an important role in sustaining oil production, especially from a mature field when the reservoirs’ natural energy becomes insufficient. However, optimally allocation of the gas injection rate in a large field through its gas-lift network system towards maximization of oil production rate is a challenging task. The conventional gas-lift optimization problems may become inefficient and incapable of modelling the gas-lift optimization in a large network system with problems associated with multi-objective, multi-constrained, and limited gas injection rate. The key objective of this study is to assess the feasibility of utilizing the Genetic Algorithm (GA) technique to optimize t</p> ... Show More

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Publication Date

Thu Jun 30 2011

Journal Name

Al-khwarizmi Engineering Journal

Nahrain Mobile Learning System (NMLS)

Nahrain mobile learning system

short message service

wireless application protocols

multimedia messaging service

mobile learning

personal digital assistant

wireless fidelity

general packet radio service

extensible hypertext markup language

java database connectivity

Mahmood Sami

Mumtaz

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The work in this paper involves the planning, design and implementation of a mobile learning system called Nahrain Mobile Learning System (NMLS). This system provides complete teaching resources, which can be accessed by the students, instructors and administrators through the mobile phones. It presents a viable alternative to Electronic learning. It focuses on the mobility and flexibility of the learning practice, and emphasizes the interaction between the learner and learning content. System users are categorized into three categories: administrators, instructors and students. Different learning activities can be carried out throughout the system, offering necessary communication tools to allow the users to communicate with each other

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Publication Date

Tue Jun 04 2024

Journal Name

Int. J. Operational Research

Pascal’s triangle graded mean defuzzification approach for solving fuzzy assignment models by using pentagonal fuzzy numbers

centroid formula

centroid formula integration

CFI

fuzzy assignment models

FAMs

optimal solution

Opt. Sol.

Pascal’s triangle graded mean

PT-GM

pentagonal fuzzy numbers

PFNs.

Zeina

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The fuzzy assignment models (FAMs) have been explored by various literature to access classical values, which are more precise in our real-life accomplishment. The novelty of this paper contributed positively to a unique application of pentagonal fuzzy numbers for the evaluation of FAMs. The new method namely Pascal’s triangle graded mean (PT-GM) has presented a new algorithm in accessing the critical path to solve the assignment problems (AP) based on the fuzzy objective function of minimising total cost. The results obtained have been compared to the existing methods such as, the centroid formula (CF) and centroid formula integration (CFI). It has been demonstrated that operational efficiency of this conducted method is exquisitely deve

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Publication Date

Mon Apr 01 2013

Journal Name

International Journal Of Electrical, Electronics And Telecommunication Engineering

Performance Analysis of xPON Network for Different Queuing Models

—Passive optical network (PON)

Interleaved Polling with Adaptive Cycle Time (IPACT)

Dynamic Bandwidth Allocation (DBA)

Queuing models

Optical line terminal (OLT)

Optical node user (ONU)

Nahlah Abdulrahman

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Passive optical network (PON) is a point to multipoint, bidirectional, high rate optical network for data communication. Different standards of PONs are being implemented, first of all PON was ATM PON (APON) which evolved in Broadband PON (BPON). The two major types are Ethernet PON (EPON) and Gigabit passive optical network (GPON). PON with these different standards is called xPON. To have an efficient performance for the last two standards of PON, some important issues will considered. In our work we will integrate a network with different queuing models such M/M/1 and M/M/m model. After analyzing IPACT as a DBA scheme for this integrated network, we modulate cycle time, traffic load, throughput, utilization and overall delay

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Publication Date

Wed Apr 25 2018

Journal Name

Ibn Al-haitham Journal For Pure And Applied Sciences

Different Estimation Methods for System Reliability Multi-Components model: Exponentiated Weibull Distribution

Exponentiated Weibull Distribution (EWD)

Reliability of multi-component Stress â€“ Strength models R(s

k)

Maximum likelihood estimator (MLE)

Moment estimator (MOM)

shrinkage method (Sh)

Least Squares Estimator (LS)

Rank Set Sampling (RSS). and mean squared error (MSE).

Abbas Najim

Fatima Hadi

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In this paper, estimation of system reliability of the multi-components in stress-strength model R_(s,k) is considered, when the stress and strength are independent random variables and follows the Exponentiated Weibull Distribution (EWD) with known first shape parameter Î¸ and, the second shape parameter Î± is unknown using different estimation methods. Comparisons among the proposed estimators through Monte Carlo simulation technique were made depend on mean squared error (MSE) criteria

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Publication Date

Wed Jan 02 2019

Journal Name

Journal Of The College Of Languages (jcl)

A traditional model of translation: Critical analysis: Традиционные модели перевода: критический анализ

traditional translation models

theory of formal and dynamic equivalence

theory of regular correspondences

informative

situational-denotative

functional-pragmatic theory of communication levels.

традиционные модели перевода

теория формальной и динамической эквивалентности

теория закономерных соответствий

информативная

ситуативно-денотативная

функционально-прагматическая теория уровней коммуникации

Ali Kadhim

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The article critically analyzes traditional translation models. The most influential models of translation in the second half of the 20th century have been mentioned, among which the theory of formal and dynamic equivalence, the theory of regular correspondences, informative, situational-denotative, functional-pragmatic theory of communication levels have been considered. The selected models have been analyzed from the point of view of the universality of their use for different types and types of translation, as well as the ability to comprehend the deep links established between the original and the translation.

Аннотация

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Publication Date

Fri Mar 01 2019

Journal Name

Applied Acoustics

Theoretical model of absorption coefficient of an inhomogeneous MPP absorber with multi-cavity depths

Micro-perforated panel (MPP) absorber has been known as an alternative absorber to classical porous material given its facile installation

long durability

environmental friendliness and attractive appearance. Extensive studies of MPP absorber proposing the improvement of its absorption frequency bandwidth have been published. This study presents a MPP absorber introduced with inhomogeneous perforations and with multi-cavity depths. The MPP is divided into two sub-area

where each area has different hole diameter

perforation ratio and a separated backed cavity depth. The acoustic impedance is modelled using electrical equivalent circuit and the absorption coefficient is calculated under normal-incidence of sound. It is found that the inhomogeneous MPP can have good bandwidth of absorption by designing the sub-MPP of smaller perforation ratio with large hole diameter and the one having the larger perforation ratio with smaller hole diameter. The absorption bandwidth can be conveniently controlled by adjusting the cavity depth of each sub-MPP. The results from the experimental work show good agreement with the theoretical model.

Ali Ibrahim

Azma

Roszaidi

Iwan

Al-Ameri

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Publication Date

Sat Oct 01 2016

Journal Name

Journal Of Theoretical And Applied Information Technology

Factors affecting global virtual teams’ performance in software projects

Today the trend is to perform software development work via distributed geographical area among team

individual or even as an organization. However

due to the global market and international presence of many companies

there is a need to implement a global virtual teams. The global virtual team members are gradually engaged in globalized business environments across space

time and organizational boundaries via information and communication technologies. A global virtual team relies on communication

collaboration

and information exchange are the most important criteria in global virtual teams’ operations. The purpose of this paper is to answer two research questions. The first research question is to identify the factors affecting global virtual teams’ performance. A systematic literature review was conducted to answer the first research question. The second research question is on what the rank of the factor affecting the global virtual teams’ performance according to their level of effect on global virtual teams’ performance. Online survey was conducted within 103 developers and IT managers from eight IT companies to answer the second research question. The Statistical Package for Social Science (SPSS 22) was used to analyze the collected data. In this study

we investigated factors that affect global virtual teams’ performance

factors considered include cultural differences

language problems

time-zone differences

team size

technical problems

lack of trust

lack of sufficient training

and ICT problems. Also the findings indicated that lack of sufficient training is the highest level of effect on global virtual teams’ performance. On the other hand

Ali Yahya Gheni

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