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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
Sun Feb 03 2019
Journal Name
Journal Of The College Of Education For Women
The effect of story- grammar instruction on poor college student s 'achievement of narrative texst theme identification
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Publication Date
Fri Mar 31 2017
Journal Name
Iraqi Journal Of Pharmaceutical Sciences ( P-issn 1683 - 3597 E-issn 2521 - 3512)
The Effect of some Variables on the Formulation of Captopril as Tablets Shaymaa Nazar Al – Sammarrai
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Captopril is an angiotensin converting enzyme inhibitor (ACEI) used to treat hypertension,
congestive heart failure, and myocardial infraction.
The only dosage form available for captopril is the plain tablet in strength of 12.5,25,50 and 100mg
tablet.
This investigation is concerned with factors affecting the formulation of captopril as a plain
tablet dosage form of 50mg. Many trials were made to prepare satisfactory tablets for the drug by
using wet – granulation methods with various additives. It was found that poly vinyl pyrrolidone
(P.V.P.) as binder gave the most satisfactory tablets. At the same time a shorter disintegrantion time
and slower dissolution rate were obtained with the addition of starch

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Publication Date
Thu Mar 01 2018
Journal Name
Journal Of Baghdad College Of Dentistry
Waterpipe Smoking Effect on Clinical Periodontal Parameters, Salivary Flow Rate and Salivary pH in Chronic‎ Periodontitis Patient
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Publication Date
Fri Jul 21 2023
Journal Name
Journal Of Engineering
The Effect of Variable Load on Dynamic Behavior of Thin Pipe by Hamilton Principle and Cfx-Ansys
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This paper presents the study and analysis, analytically and numerical of circular cylindrical shell pipe model, under variable loads, transmit fluid at the high velocity state (fresh water). The analytical analysis depended on the energy observation principle (Hamilton Principle), where divided all energy in the model to three parts , strain energy, kinetic energy and transmitted energy between flow and solid (kinetic to potential energy). Also derive all important equations for this state and approach to final equation of motion, free and force vibration also derived. the relations between the displacement of model function of velocity of flow, length of model, pipe thickness, density of flowed with location coordinate x-axis and angle

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Publication Date
Sat Jun 01 2013
Journal Name
Journal Of Baghdad College Of Dentistry
The Effect of SOLO and Sodium Hypochlorite Disinfectant on Some Properties of Different Types of Dental Stone
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Dental casts come into direct contact with impression materials and other items that are contaminated by saliva and blood from a patient's mouth, leaving the casts susceptible to cross-contamination. The disinfectant solutions of the impression materials cause various adverse reactions. Therefore, disinfection of dental casts may be effective in preventing cross infection. This study was carried out to evaluate the surface hardness, dimensional accuracy, reproduction of details and surface porosity of type III, type IV and type IV extra hard dental stone after immersion in and spray by using SOLO and Sodium hypochlorite disinfectant solutions. Materials and methods: 240 Stone samples were prepared in rubber rings, A total of 60 test block w

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Publication Date
Sun Oct 01 2017
Journal Name
International Journal Of Science And Research (ijsr)
Effect of Elevated Temperature on the Compressive Strength of Reactive Powder Concrete (RPC) Containing Polyvinyl Chloride (PVC)
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Fire is the most sever environmental condition affecting on concrete structures, thus investigating for fire safet, IJSR, Call for Papers, Online Journal

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Publication Date
Thu Jun 29 2023
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
The Effects of Operating Variables on Efficancy of Water Disinfection by Sodium Hypochlorite Using Al-Wathba Wastewater
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The aim of this investigation was to study the impact of various reaction parameters on wastewater taken from Al-Wathba water treatment plant on Tigris River in south of Baghdad, Iraq with sodium hypochlorite solution. The parameters studied were sodium hypochlorite dose, contact time, initial fecal coliform bacteria concentration, temperature, and pH. In a batch reactor, different concentrations of sodium hypochlorite solution were used to disinfect 1L of water. The amount of hypochlorite ions in disinfected water was measured using an Iodimetry test for different reaction times, whereas the Most Probable Number (MPN) test was used to determine the concentration of coliform bacteria. Total Plate Count (TPC) was utilized in this study to

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Publication Date
Wed Oct 16 2013
Journal Name
International Journal Of Pharmacy And Pharmaceutical Sciences
Effects of mucoadhesive polymers combination on the properties of lisinpril buccal tablets prepared by wet granulation method
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Publication Date
Mon Mar 31 2014
Journal Name
Iraqi Journal Of Chemical And Petroleum Engineering
Evaluation of Sodium Chloride and Acidity Effect on Corrosion of Buried Carbon Steel Pipeline in Iraqi Soil
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In this work, corrosion parameters were evaluated using potentiodynamic polarization curves. In order to determine corrosion parameters of potential and current density of the interesting metal, carbon steel, environmental conditions of external corrosion of buried carbon steel pipeline in Iraqi soil were prepared in the laboratory using simulated prepared conditions. Solutions of sodium chloride at different concentrations (300, 1100, 1900, 2700, and 3500 ppm) were used. pH of solution were acidic at pH =5, and alkaline at pH = 9. Laboratory conditions were similar to those of Iraqi soil where the pipelines were buried. Temperature was constant at 20 °C. Potentiodynamic polarization curves, of potential vs. log current density, were ob

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Publication Date
Sun Nov 20 2022
Journal Name
Journal Of New Zealand Studies
The Impacts of Environmental-Geomorphology of the Kut Barrage on the Tigris Waterway and the Neighboring regions
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The research dealt with the effect of Kut Barrage on the geomorphological processes and the natural environment system in the course of the Tigris between the cities of Al-Ahrar and Kut in central Iraq. It was clear from the research the contribution of Kut Barrage in changing the surface runoff system between the front and back of the barrage, as well as changing the type of processes and the prevailing geomorphic forms, as the sedimentation activates the front of the barrage and erosion at its back, which affected the change in the morphology of the river, sediment retention at the front of the barrage, the burial of the bottom and reducing the validity of the stream. This also affects the efficiency of the barrage’s work and coastal er

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