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Downlink Training Design for FDD Massive MIMO Systems in the Presence of Colored Noise
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Massive multiple-input multiple-output (MaMi) systems have attracted much research attention during the last few years. This is because MaMi systems are able to achieve a remarkable improvement in data rate and thus meet the immensely ongoing traffic demands required by the future wireless networks. To date, the downlink training sequence (DTS) for the frequency division duplex (FDD) MaMi communications systems have been designed based on the idealistic assumption of white noise environments. However, it is essential and more practical to consider the colored noise environments when designing an efficient DTS for channel estimation. To this end, this paper proposes a new DTS design by exploring the joint use of spatial channel and noise covariance matrices, when the channel is not reciprocal but the coherence block length remains limited. We derive an analytical solution for the mean square error (MSE) based on the proposed training design with colored noise. In addition, this paper exploits the method of random matrix theory to provide an analytical solution for the downlink (DL) achievable sum rate of the regularized zero forcing beamforming (RZFBF) precoder. Numerical results demonstrate that using the proposed DTS design, the MSE of the channel estimate is significantly reduced compared with the conventional training designs with white noise. Furthermore, the results show that the proposed pilot design markedly improves the DL achievable SR over the conventional training designs, especially at relatively low signal-to-noise-ratio (SNR) levels. This enables FDD MaMi systems to operate under more practical scenarios of colored noise and limited coherence time environments.

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Publication Date
Wed Mar 15 2023
Journal Name
Al-academy
The Role of Context in Graphic Design
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The need for an intellectual understanding of the context from many aspects' dictates understanding the ways through which the graphic designer walks in simulating the intent of the design process and elevating it to levels of communicative perception that leads to communicating the idea to the recipient, and it is thus a need closely related to the context, if it is historical. Culturally or socially, and between the mechanisms of selecting and operating the elements and units of the graphic and design achievement. On this basis, the role of context in graphic design can be studied.

The research included four chapters, the first chapter of the research problem and the need for it, and the aim of the research was (discovering the

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Publication Date
Tue Dec 01 2020
Journal Name
Journal Of Economics And Administrative Sciences
Robust estimation of multiple linear regression parameters in the presence of a problem of heterogeneity of variance and outliers values
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Often times, especially in practical applications, it is difficult to obtain data that is not tainted by a problem that may be related to the inconsistency of the variance of error or any other problem that impedes the use of the usual methods represented by the method of the ordinary least squares (OLS), To find the capabilities of the features of the multiple linear models, This is why many statisticians resort to the use of estimates by immune methods Especially with the presence of outliers, as well as the problem of error Variance instability, Two methods of horsepower were adopted, they are the robust weighted least square(RWLS)& the two-step robust weighted least square method(TSRWLS), and their performance was verifie

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Publication Date
Sun Jun 30 2019
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Evaluation the Effect of Velocity and Temperature on the Corrosion Rate of Crude Oil Pipeline in the Presence of CO2/H2S Dissolved Gases
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In this paper investigate the influences of dissolved CO2/H2S gases, crude oil velocity and temperature on the rate of corrosion of crude oil transmission pipelines of Maysan oil fields southern Iraq. The Potentiostatic corrosion test technique was conducted into two types of carbon steel pipeline (materials API 5L X60 and API 5L X80). The computer software ECE electronic corrosion engineer was used to predict the influences of CO2 partial pressure, the composition of crude oil, flow velocity of crude oil and percentage of material elements of carbon steel on the rate of corrosion. As a result, the carbon steel API 5L X80 indicates good and appropriate resistance to corrosion compared to carbon steel API

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Publication Date
Sun Jan 27 2019
Journal Name
Journal Of Accounting And Financial Studies ( Jafs )
Impact dimensions the Training process of the in components intellectual capital: Exploratory search in the National Insurance Company
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The concept of training is no longer traditionally understood Limited organize traditional training courses, but has become a strategic choice in the investment and development of human resources system, attic trying to find the answer to the core problem of the study which

is the extent to which the training process, the traditional form that meets the needs of the company the development of intellectual capital.This research aimstostatementof the impact dimensions the training process(training role, support or top management , training programs, modern technology)of the in components Intellectual Capital(Human Capital, Structural Capital, Customer Capital) and provide the top management of the Company for the development of sci

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Publication Date
Mon Sep 26 2022
Journal Name
Journal Of Advanced Research In Hr And Organizational Management
Entrepreneurial Performance of the Organization According to the Approved Training Strategy
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The research aims to determine the role of the training strategy with its dimensions of (strategic analysis, formulation of training strategy, implementation of training strategy, evaluation) in the pioneering performance of the organization with its dimensions of (pre-planning , renewal and modernization, efficiency, effectiveness). Important and modern in pioneering performance and training strategy, and in recognition of the importance of the subject and the expected results of the surveyed banks, an analysis was made of the data obtained through field visits in addition to the questionnaire and interviews ,and the most prominent results that were reached were taking the research sample into consideration all the requirements of the trai

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Publication Date
Sun Sep 07 2014
Journal Name
Baghdad Science Journal
A Study Of Corrosion Inhibition Of Low Carbon Steel In Washing Water Of Crude Oil Solution In The Presence Of Folic Acid
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The corrosion behavior of low carbon steel in washing water of crude oil solution has been studied potentiostatically at five temperatures in the range (30–70)°C .The corrosion potential shifted to more negative values with increasing temperature and the corrosion current density increased with increasing temperature. Folic acid had on inhibiting effect on the corrosion of low carbon steel in washing water at a concentration (5× 10-4-- 5× 10-3 ) mol/dm3 over the temperature range (30–70)°C. Values of the protection efficiency were calculated from the corrosion current density .From the general results for this study, it can be seen that thermodynamic and kinetic function were also calculated (?G, ?S, ?H and Ea )

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Publication Date
Sat Jan 01 2022
Journal Name
Journal Of The Mechanical Behavior Of Materials
Identifying the selection criteria of design consultant for Iraqi construction projects
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Abstract<p>The quality and cost of constructed buildings are heavily influenced by the performance of design/auditing consultants. Thus, selecting the right design consultant and design auditing consultants is of utmost importance and not an easy task for any construction client. so, the client should specify the efficiency criteria and assess the performance levels of the design and design auditing consultant firm. The study aims to identify the selection criteria of the design consultant in construction projects and also identify the selection criteria of the design auditing consultant for the construction projects by using the Delphi survey with applying the principal components analysis (PCA</p> ... Show More
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Publication Date
Fri Jan 01 2016
Journal Name
Journal Of The Electrochemical Society
Electrochemical Incineration of Oxalic Acid at Manganese Dioxide Rotating Cylinder Anode: Role of Operative Parameters in the Presence of NaCl
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A detailed experimental study was devoted to the anodic oxidation of oxalic acid using manganese dioxide rotating cylinder anode with the objective to evaluate in a systematic way the effect on the oxalic acid oxidation process of several relevant parameters, including the presence of sodium chloride, the current density (J), the rotation speed, the temperature, and the initial concentration of oxalic acid. Thin manganese dioxide film on graphite substrate has been prepared by electrochemical oxidation from MnSO4-H2SO4 electrolyte. The morphology of this electrode was investigated by XRD, SEM, EDS and AFM techniques. The results show that a firm γ-structure of MnO2 film on graphite rod can be obtained successfully. The results indicate tha

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Publication Date
Sun Feb 01 2015
Journal Name
Journal Of Economics And Administrative Sciences
The use of modern management accounting systems for continuous improve the performance of Jordanian Industrial Companies
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        The intensification of competition among all companies and at different levels has become necessary for every company need to continue to improve its performance in order to be able to face the competition and stay in the market. To achieve this, we must rely on the company's accounting information more accurate and appropriate and provided in a timely manner, for the purpose of use in planning and decision making.

So there must be information systems that help the administration to continuous development and improvement of the performance of companies in general, and this is what you need Jordanian companies, especially after the accession of Jordan to the field

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Publication Date
Thu Jun 30 2016
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Modelling and Optimization of Carbon Steel Corrosion in CO2 Containing Oilfield Produced Water in Presence of HAc
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Previously, many empirical models have been used to predict corrosion rates under different CO2 corrosion parameters conditions. Most of these models did not predict the corrosion rate exactly, besides it determined effects of variables by holding some variables constant and changing the values of other variables to obtain the regression model. As a result the experiments will be large and cost too much. In this paper response surface methodology (RSM) was proposed to optimize the experiments and reduce the experimental running. The experiments studied effects of temperature (40 – 60 °C), pH (3-5), acetic acid (HAc) concentration (1000-3000 ppm) and rotation speed (1000-1500 rpm) on CO2 corrosion performance of t

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