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Medium access control protocol design for wireless communications and networks review
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<p><span>Medium access control (MAC) protocol design plays a crucial role to increase the performance of wireless communications and networks. The channel access mechanism is provided by MAC layer to share the medium by multiple stations. Different types of wireless networks have different design requirements such as throughput, delay, power consumption, fairness, reliability, and network density, therefore, MAC protocol for these networks must satisfy their requirements. In this work, we proposed two multiplexing methods for modern wireless networks: Massive multiple-input-multiple-output (MIMO) and power domain non-orthogonal multiple access (PD-NOMA). The first research method namely Massive MIMO uses a massive number of antenna elements to improve both spectral efficiency and energy efficiency. On the other hand, the second research method (PD-NOMA) allows multiple non-orthogonal signals to share the same orthogonal resources by allocating different power level for each station. PD-NOMA has a better spectral efficiency over the orthogonal multiple access methods. A review of previous works regarding the MAC design for different wireless networks is classified based on different categories. The main contribution of this research work is to show the importance of the MAC design with added optimal functionalities to improve the spectral and energy efficiencies of the wireless networks.</span></p>

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Publication Date
Fri Aug 18 2023
Journal Name
Medicinal Chemistry Research
New tolfenamic acid derivatives with hydrazine-1-carbothioamide and 1,3,4-oxadiazole moieties targeting VEGFR: synthesis, in silico studies, and in vitro anticancer assessment
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Publication Date
Sun Jun 11 2017
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Study of Percentage of Red and White Muscles in Two Species of Bony Fishes Tenualosa ilisha (Hamilton , 1822) and Cyprinus carpio (Linnaeus , 1758)
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 The present study aimed to estimate percentage of red and white muscles fibers in two species of bony fishes belong to two different families which represented by Tenualosa ilisha (Hamilton , 1822) that belongs to the family Clupeidae and Cyprinus carpio (Linnaeus , 1758) that belongs to the family Cyprinidae . The samples were collected from local market at holy Karbala province. The results show difference clear in mean values of muscles numbers at different studied length groups, and the percentage of red muscles fibers were less than that of white muscle fibers at different body regions (R1,R2,and R3) among species.  The total average of red muscle fibers values ranged between (4.23 - 11.08 %) while the total average of wh

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Publication Date
Sat May 01 2021
Journal Name
Journal Of Engineering
Impact of the Weir Slit Location, the Flow Intensity and the Bed Sand on the Scouring Area and Depth at the Dam Upstream
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A total of 48 experiments were conducted to investigate the impact of slit weir dimensions and locations on the maximum scour depth and scour area created upstream. The slit weir model was a 110 mm slit opening, and it was installed at the end of the working section in a laboratory flume. The flume was 10.0 m long, 30 cm wide, 30 cm deep, and almost middle. It includes a 2 m working section with a mobile bed with 110 mm in thickness. In the mobile bed, two types of nonuniform sand (with a geometric standard deviation of 1.58 and 1.6) were tested separately. The weir dimensions and location were changed with flow rates. Then dimensions of the slit weir were changed from 60 x 110 mm to 60 x 70 mm (width x height), while th

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Publication Date
Tue Jan 01 2019
Journal Name
Aip Conference Proceedings
Studying the partial substitution of barium with cadmium oxide and its effect on the electrical and structural properties of HgBa2Ca2Cu3O8+δ superconducting compound
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Publication Date
Sat May 11 2024
Journal Name
Tech Hub Journal
The prevailing leadership Patterns and personal traits and their relationship to innovative thinking of female physical education teachers in middle schools in Baghdad
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Teachers play a critical role in planning, organizing, coordinating, monitoring, and instructing, hence the topic of leadership styles receives a lot of attention. As a result, the physical education school is regarded as the most significant component of the educational process because it has the ability to weave together the teaching and educational skills, attitudes, and capacities that its students develop. Fits into their identities through her relationship with them. Teachers play a critical role in planning, organizing, coordinating, monitoring, and instructing, hence the topic of leadership styles receives a lot of attention. As a result, the physical education school is regarded the most significant aspect in the educational proces

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Publication Date
Thu May 17 2018
Journal Name
Ibn Al-haitham Journal For Pure And Applied Sciences
Synthesis , Characterization and Study of Biological Activity of Some New Schiff Bases ,1,3-Oxazepine and Tetrazole Derived from 2,2 di thiophenyl Acetic Acid
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         In this study  new  derivatives  of  Schiff bases 5-8 , 1,3- oxazepine  9-16 and tetrazoles 17-19 have  been synthesized from the new starting  material 1 which has  synthesized  the reaction of  one mole of dichloro acetic acid and two moles of  thiophenol , the esters  2-3 were synthesized from the reaction of  compound 1 with methanol or ethanol respectively  in the presence of  H2SO4  as  catalyst  then 2,2-dithiophenylaceto Hydrazide  4 were synthesized from the reaction of  2 or 3 with hydrazine hydrate  80 % , Schiff bases 5-8 were  synthesized from the

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Publication Date
Tue Jul 15 2025
Journal Name
Journal Of Baghdad College Of Dentistry
Caries severity in relation to oral health knowledge and behavior of third and fifth year dental students / University of Baghdad (A comparative study)
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Background: Tooth wear is one of the most common problems in the older dentate population which results from the interaction of three processes (attrition, abrasion and erosion) and it affects all societies, different age groups, and all cultures. This study was achieved to evaluate the prevalence and distribution of tooth wear among institutionalized residents in Baghdad city\ Iraq. Subjects and Methods: This survey was accomplished on four private and one governmental institution in Baghdad city. One-hundred twenty three (61 males, 62 females) aged 50-89 years were participated in this study. The diagnosis and recording of tooth wear were according to criteria of Smith and Knight. Results: The prevalence of tooth wear was 100% with a mean

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Publication Date
Thu Dec 26 2019
Journal Name
Bulletin Of The Iraq Natural History Museum (p-issn: 1017-8678 , E-issn: 2311-9799)
COMPARATIVE ANATOMICAL AND HISTOLOGICAL STUDY OF SOME ORGANS IN TWO FISH SPECIES CYPRINUS CARPIO LINNAEUS, 1758 AND MESOPOTAMICHTHYS SHARPEYI (GÜNTHER, 1874)(CYPRINIFORMES, CYPRINIDAE)
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  The present study aims to give some details about the normal anatomical and histological structure of the liver, pancreas and gall bladder in Cyprinus carpio Linnaeus, 1758 and Mesopotamichthys sharpeyi (Günther, 1874). Anatomical results revealed that the liver of C. carpio is a reddish-brown in color, located in the anterior part of abdominal cavity and dispersed between most of the intestines, which is divided into two lobes; while in M. sharpeyi the liver is light brown in color located in the anterior part of abdominal cavity and extends to the end of the intestinal tract with two lobs. The gallbladder situated in the right side of the liver in both species. Histological results in both species showed that the liver consists

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Publication Date
Mon Jan 01 2018
Journal Name
Journal Of Biodiversity And Environmental Sciences (jbes)
Effect of potassium fertilization and organic nutrient (Reef Amirich) in the population density of Bemisia tabaci (Genn.) and Thrips tabaci (L.) on cucumber
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A field study was conducted at the college of Agriculture, Baghdad University-Jadiriyah to investigate the effect of adding potassium fertilizer and organic nutrient (Reef Amirich) on the population density of two sucking pests of cucumber, cotton whitefly, Bemisia tabaci and onion thrips, Thrips tabaci during the spring season/2016. Results indicated that potassium sulphate (50, 100 and 150 kg/ha) and organic nutrient (0.8 and 1.6ml/l) reduced both the population density of B. tabaci and T. tabaci nymphs depending on the fertilizer level of the user, the treatment 150 kg/ha for the potassium fertilizer and 1.6 ml/L for organic nutrient was the highest among others when minimized density of nymphs by 1.62 nymphs of B. tabaci/disk leaf and 0

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Publication Date
Sat Jun 25 2022
Journal Name
International Journal Of Drug Delivery Technology
Comparison of Sizes of Zinc Oxide Nanoparticles Extracted from Staphylococcus lugdunensis and Berberis vulgaris Plant Extract Against Some Types of Bacteria and Yeast
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Staphylococcus lugdunensis, isolation between 12.5 to 1.8% routine works may be a possible peroral route of infective endocarditis and found in the oral cavity by examined using saliva. Similar supragingival plaque isolation was observed. The increased bacteria resistance to antibiotics multiple have led to novel methods for resistance bacteria; antimicrobial agents are well known (ZnO NPs) by biological method and are lower toxicity and biology safety ZnNOPs activity by plant extraction and less toxicity as well as bio-safe. The nanoparticle was synthesized by biological method (Green) by barberry (Berberis vulgaris) extract. In this study using (WAD) method using different concentrations between (128, 64, 32, and 16) mg/mL of ZnO NPs, The

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