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Performance evaluation of frequency division duplex (FDD) massive multiple input multiple output (MIMO) under different correlation models
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Massive multiple-input multiple-output (massive-MIMO) is considered as the key technology to meet the huge demands of data rates in the future wireless communications networks. However, for massive-MIMO systems to realize their maximum potential gain, sufficiently accurate downlink (DL) channel state information (CSI) with low overhead to meet the short coherence time (CT) is required. Therefore, this article aims to overcome the technical challenge of DL CSI estimation in a frequency-division-duplex (FDD) massive-MIMO with short CT considering five different physical correlation models. To this end, the statistical structure of the massive-MIMO channel, which is captured by the physical correlation is exploited to find sufficiently accurate DL CSI estimation. Specifically, to reduce the DL CSI estimation overhead, the training sequence is designed based on the eigenvectors of the transmit correlation matrix. To this end, the achievable sum rate (ASR) maximization and the mean square error (MSE) of CSI estimation with short CT are investigated using the proposed training sequence design. Furthermore, this article examines the effect of channel hardening in an FDD massive-MIMO system. The results demonstrate that in high correlation scenarios, a large loss in channel hardening is obtained. The results reveal that increasing the correlation level reduces the MSE but does not increase the ASR. However, exploiting the spatial correction structure is still very essential for the FDD massive-MIMO systems under limited CT. This finding holds for all the physical correlation models considered.

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Publication Date
Tue Dec 11 2018
Journal Name
Baghdad Science Journal
Effect of irrigation by saline magnetized water on seed germination and seedling growth of wheat Triticum aestivum
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The effect of saline magnetized water irrigation on seed germination and seedling growth of wheat cultivar Iraq were studied. Irrigation water was supplemented with different levels of Sodium chloride 6, 12 or 18 mmhos/ cm in addition control treatment, and passed through a proper magnetic felid with 1000, 1250, 1500 or 2000 gaus in addition control treatment. The results showed significantly stimulated shoot development and led to the increase of germination, seedling emergence, area leaf, length of shoot and root and fresh and dry weight compared to the controls. Results also showed significant interaction between saline water and magnetized water. So, using magnetic treatment of saline water could be a promising technique

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Publication Date
Sun Oct 01 2017
Journal Name
Al–bahith Al–a'alami
The Diversity of Cultures and Ideologies in Society and its Impact on the Structure of Iraqi press
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The diversity of cultures is still the title of an Iraqi specificity that gave the society a diversity and this is reflected in the journalistic reality with the changing of the political system generate a new political and ideological life that differs from what is prevailed during the decades. However, its exacerbation of the degree of division is an additional duty for the press as a cultural platform and a knowledge bridge that contributes to the process of dialogue, addressing the differences, establishing a politically homogeneous structure through the state and socially by uniting all components of society and working to raise public awareness of the importance of national belonging to build a modern state. Cultural diversity is a

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Publication Date
Sun May 07 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study the Effect of Annealing Temperature on the Structural, Optical and Electrical Properties of ZnS Thin Films
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The structural, optical and electrical properties of ZnS films prepared by vacuum
evaporation technique on glass substrate at room temperature and treated at different
annealing temperatures (323, 373, 423)K of thickness (0.5)µm have been studied. The
structure of these films is determined by X-ray diffraction (XRD). The X-ray diffraction
studies show that the structure is polycrystalline with cubic structure, and there are strong
peaks at the direction (111).
The optical properties investigated which include the absorbance and transmittance
spectra, energy band gab, absorption coefficient, and other optical constants. The results
showed that films have direct optical transition. The optical band gab was

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Publication Date
Sat Dec 30 2023
Journal Name
Iraqi Journal Of Science
Radiations and Extinctions of Maastrichtian Rudist bivalve and Benthic Foraminifera of Aqra Formation Kurdistan Region Northern Iraq
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During the Maastrichtian, the rudists and benthic foraminifera of Aqra Formation underwent two major radiations, the first beginning in early Early Maastrichtian and peaking in the late Early Maastrichtian, and sconed extending from the early Late Maastrichtian to a late Late Maastrichtian peak.The radiations were punctuated and separated by prominent extinction episodes, fit with global Maastrichtian mass extinction.The high level of rudist, endemism [90%] allows definition of true regional origination and extinction pattern; these may represent global pattern for rudists. Radiation and extinction patterns in the northern Iraq [Kurdistan Region] can be variously related to relative sea level fluctuation and the rate of food and clastic

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Publication Date
Fri Jul 28 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Levels of Trace and Essential Elements in Sera of Chronic Renal FAilure Patients Before and After Dialysis
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        This study included a group of (15) chronic renal failure patients (CRF), an addition group of (15) healthy individual  was concluded in this study for control. Trace and essential elements ( Zn, Cu , Ca , K , Na) were measured by atomic absorption and flam analyzer in sera of CRF patients pre and post dialysis and control groups. The results showed a significant ( p < 0.05) increase in Zn and k+ concentration in sera of CRF patients pre and post dialysis compared to the control group. While there is a significant decrease for copper concentration in sera of CRF patients pre and post dialysis compared to the control group.       There was no significant alte

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Publication Date
Sun Dec 01 2013
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
FAUNA AND FLORA OF HAWRAMAN MOUNTAIN (Part one) HAWRAMAN LOWEST ZONE, KURDISTAN PROVINCE NORTH EAST OF IRAQ
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    In this study we try to make a first step for making a new list for fauna and flora of Kurdistan in particular and Iraq in general. This is very important study of biodiversity of Iraq. We recognize 52 migratory and resident birds including Alectoris chukar asoica which is recently described. Also, 20 amphibians and reptiles including two snakes recently recorded Zamenis hohenackeri and Platyceps ladacesis, a new form of Asaccus sp. and sub- species of Varanuns griseus caspeius for the first time in Iraq, with many rare specimens. Thirteen different species of mammals were recognized, with comme

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Publication Date
Thu Feb 01 2018
Journal Name
Journal Of Economics And Administrative Sciences
Compare between result of analysis of variance after and before use analysis covariance to Split-blocks design
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This research aims to study the important of the effect of analysis of covariance manner for one of important of design for multifactor experiments, which called split-blocks experiments design (SBED) to deal the problem of extended measurements for a covariate variable or independent variable (X) with data of response variable or dependent variable Y in agricultural experiments that contribute to mislead the result when analyze data of Y only. Although analysis of covariance with discussed in experiments with common deign, but it is not found information that it is discussed with split-Blocks experiments design (SBED) to get rid of the impact a covariance variable. As part application actual field experiment conducted, begun at

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Publication Date
Fri Jun 28 2019
Journal Name
Journal Of The College Of Education For Women
The most important ministers of the Abbasid state until the end of the era (198-218 AH)
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The existence of succession system has appeared in Arab Islamic state after the death of the prophet Mohammed (peace be upon God and peace), So there was caliphate, then the Umayyad dynasty in Syria , until 132 AH , the date o the emergence of the Abbasid state adopted a system ministry formally , hafs bin sulaiman ( Abu salamah Khallal ) was the first  minister emerged on the political scene. He was killed at the time of the first  Abbasid caliph , Abu Albbas , incest 132-136 who had put Khalid bin barmak as a minister instead of Hafs bin Sulaiman . During the reign of AL-Mansur 136-158 , there was an importance and a place for the ministry , despite of AL-Mansur strength personality that covered on his ministers personalities

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Publication Date
Wed Jan 03 2024
Journal Name
Al-rafidain Journal Of Medical Sciences ( Issn 2789-3219 )
Proficiency and Knowledge of Community Pharmacists in the Use of Liraglutide and Semaglutide as Weight Reduction Agents
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Background: In recent years, the prevalence of obesity has climbed sharply. Still, only a few safe and effective medications are approved as weight-loss drugs. Objective: This study aims to assess the knowledge and practice of community pharmacists in Iraq regarding the use of Liraglutide and Semaglutide as weight-loss medications. Method: A cross-sectional survey was implemented using a validated questionnaire and a convenient sample of Iraqi community pharmacists from different governorates. The questionnaire was created after conducting a literature review of the most important articles about liraglutide and semaglutide. The questionnaire consists of three sections. The first part was used to collect demographic information. The second a

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Publication Date
Thu Apr 18 2024
Journal Name
Iraqi Journal Of Soil Science
EFFECT OF SPRAYING POTASSIUM SULFATE AND BIOZYME ON THE UALITATIVE CHARACTERISTICS OF CAULIFLOWER (Brassica oleracea var. botrytis)
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