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Downlink Training Sequence Design Based on Waterfilling Solution for Low-Latency FDD Massive MIMO Communications Systems
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Future generations of wireless communications systems are expected to evolve toward allowing massive ubiquitous connectivity and achieving ultra-reliable and low-latency communications (URLLC) with extremely high data rates. Massive multiple-input multiple-output (m-MIMO) is a crucial transmission technique to fulfill the demands of high data rates in the upcoming wireless systems. However, obtaining a downlink (DL) training sequence (TS) that is feasible for fast channel estimation, i.e., meeting the low-latency communications required by future generations of wireless systems, in m-MIMO with frequency-division-duplex (FDD) when users have different channel correlations is very challenging. Therefore, a low-complexity solution for designing the DL training sequences to maximize the achievable sum rate of FDD systems with limited channel coherence time (CCT) is proposed using a waterfilling power allocation method. This achievable sum rate maximization is achieved using sequences produced from a summation of the user’s covariance matrices and then applying a waterfilling power allocation method to the obtained low-complexity training sequence. The results show that the proposed TS outperforms the existing methods in the medium and high SNR regimes while reducing computational complexity. The obtained results signify the proposed TS’s feasibility for practical consideration compared with the existing DL training sequence designs.

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Publication Date
Mon Aug 01 2022
Journal Name
Baghdad Science Journal
Application of GIS technique in the studies on fish assemblages in Shatt Al-Arab River, Basrah, Iraq
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The present study has examined the spatiotemporal varieties of the demographics of the Shatt Al-Arab River fishes and their relation to some ecological components. The aim is to forecast these groups in the unexplored parts of the waterway with an emphasis on environmental indices of diversity. Three sites in the river were selected as an observation and study of these species, which lasted from March 2019 to February 2020, the study dealt with factors affecting fishes, as Water Temperature (WT), Dissolved Oxygen (DO), Potential Hydrogen Ion (pH), Salinity (Sal), and Transparency (Tra). Gill nets, cast nets, hooks, and hand nets were adopted to collecting fish. The results indicated that the fish population comprises 60 species represent

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Publication Date
Mon Jan 01 2018
Journal Name
Research Journal Of Pharmacy And Technology
Evaluation of Hesperidin Protective Effect on Lipopolysaccharide-Induced Inflammation and Lipid Peroxidation in BALB/c male mice
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Publication Date
Sat Apr 01 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
Effect of Nitrogen and Phosphorus Levels on Yield, Concentration, Physical and Chemical Properties of Dill Seed Oil
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To test the effect of 4 levels of nitrogen (i.e. 0, 45, 90 and 135 Kg N ha-1) as urea (46% N) and 3 levels of phosphorus (i.e. 0, 17.5 and 35 Kg P ha-1) as triple superphosphate (21.8% P) on yield and concentration of dill (Anethum graveolens L. local cultivar) seed oil this experiment was carried out during winter season of 1999 - 2000 at the experimental field of Agriculture College, Abu-Ghraib.

 Both fertilizers were applied in two equal splits, first at seeds sowing and the second was added one month after emergence. Dried and ground seed samples were subjected to water distillation for extraction of volatile oils

 Result indicated that fertilization of dill plants with 90 Kg N

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Publication Date
Thu Dec 01 2011
Journal Name
Journal Of Economics And Administrative Sciences
Measuring and Analysis of Demand Function on Oil derivatives of A Selected countries the Period 1985- 2008
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The subject of demand on oil derivative has occupied an important position at present time in the daily life context. The fuel of benzene and gas oil and kerosene is one of basic elements of that concern, and on local , regional and international levels. The oil derivatives have played a leading role in determining the course and nature of development since early 1970 to the present time whether in the productive Arab countries or the importing. The researcher set out from the hypothesis that the increase of the local consumer demand on some of the oil derivatives is because of the internal and external factors accompanied by the inability of the productive capability and local production to confront this increase, and the resort

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Publication Date
Tue Dec 01 2009
Journal Name
Iraqi Journal Of Physics
Effect of Polyurethane Resin Additives on the Impact Toughness of Epoxy Resin Reinforced with woven roving Glass
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I mpact strength for Epoxy/Polyurethane, Blends and their composites with two
layers of Glass fibers (0-90) are calculated.
The impact strength of the blends and composites decrease with increasing weight
by weisht percentage of polyurethane . This result is attributed to the high elasticity
of PU , and to the immiscibility between the polymer blends as well as the fiber
delaminates

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Publication Date
Fri Jan 24 2020
Journal Name
Iraqi Journal Of Agricultural Sciences
THE EFFECT OF TERMITES EXTRACT ON INHIBITION OF GROWTH OF SOME PATHOGENIC BACTERIA AND SYNTHESIS OF BIOFILM
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This study was aimed to extract the effective material from the dry nests of termites and detect its antibacterial activity against some pathogenic bacterial isolates and inhibit synthesis of its biofilm. Termites dry nests were collected and the effective material was extracted then the antibacterial activity was detected using the disc diffusion assay. Results were showed that the extract have antibacterial material from the Termites dry nests, this extract showed antibacterial activity against Gram positive bacteria (Staphylococcus aureus) at (21.5mm) and Gram negative bacteria ( Enterobacter sp. and Pseudomonas aeruginosa) at (26 mm and 20 mm) respectively by inhibiting their growth, as well as its effect on biofilm production o

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Publication Date
Wed Apr 01 2009
Journal Name
Journal Of Educational And Psychological Researches
Self-Efficacy of English Language Teachers and Its Effect On their Pupils' AchievementIn Baghdad Secondary Schools/Karkh2
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Teachers' self-efficacy plays a very important role in the process of teaching English language, and teachers have primary role in determining what is needed or what would work best with their students. The sample consists of eighty-seven English language teachers in secondary schools in Baghdad/Kaarkh2. Self-efficacy questionnaire of fifteen items was constructed. Face, content validity and reliability were verified. Then, pupils' marks for the first semester were taken as their achievement.The main finding of the study indicates that:
English language teachers' self-efficacy has effect on their pupils' achievement.
In the light of the findings of the present study, several conclusions, recommendations and suggestions for further

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Publication Date
Mon Dec 21 2020
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
SEASONAL FLUCTUATION OF STINK BUG MUSTHA SPINULOSA (LEFEBVRE, 1831) (HEMIPTERA, PENTATOMIDAE) ON SOME TREES IN ERBIL CITY
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Phytophagous stink bugs (Hemiptera, Pentatomidae) are economically important insect pests of fruit, vegetable, nut and field crops. This study was carried out during the season of 2013 in orchards within Erbil city, to follow the stink bug Mustha spinulosa (Lefebvre, 1831) seasonal fluctuation on some fruit trees: olive, plum, apricot, pear, apple and almond.
The stink bug reaches its maximum abundance throughout the second week of August (38.2/tree) coinciding with mean temperature and relative humidity of 33.40C and 28.14% respectively, and the highest total mean of the number of the insect was recorded on the olive trees (181.8/tree). The study reveals that the stink bug attacked 22 trees (fruit and forest) while it has not atta

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Publication Date
Sun Jul 01 2018
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
THE IMPORTANCE OF GEODIVERSITY ON THE ANIMAL DIVERSITY IN HUWAIZA MARSH AND THE ADJACENT AREAS, SOUTHEASTERN IRAQ
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    Geodiversity is the variety within abiotic natural elements that include: rocks, minerals, landforms, soil types, and water resources. Recently ecologists and naturalists recognized that there is close relationship between geodiversity and ecosystems. Huwaiza marsh is located south eastern Iraq within Lower Mesopotamian plain. The main rock bed units which crop out north east of the studied area comprises many types of rocks: conglomerate, sandstone, mudstone, siltstone and claystone belong to Bai Hassan, Mukdadiya and Injana Formations. The general elevation of the area ranges around 5 meters (a. s. l.) near the marsh and increase northeast to more than 100 meters (a. s. l.) and the Land forms are: cuesta, oxbow lakes

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Publication Date
Tue Sep 11 2018
Journal Name
Iraqi Journal Of Physics
The effects of silica addition on the structural, electrical and mechanical characteristics of MgAl2O4 spinel ceramic phase
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The ceramic compound Mg1-xSixAl2O4 (x= 0, 0.1, 0.2, 0.3, 0.4) was prepared from nano powder of Al2O3 and MgO doped with Nano powder of SiO2 at different molar ratios. The specimens were prepared by standard chemical solid reaction technique and sintered at 1450 oC. Structure of the specimens was analyzed by using X-ray diffraction (XRD). The X-ray patterns of the specimens showed the formation of pure simple cubic spinel structure MgAl2O4 phase with space group of ̅ . The average grain size and surface topology were studied by atomic force microscopy. The results showed that the average grain size was about 73-90 nm. The DC electrical properties of the specimen were measured. The apparent density was found to increase and the porosity a

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