<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>
BACKGROUND: In 1972 complete description of the
inflammation of posterior third of the vocal cords was
done, with barium swallow confirming Gastro
Esophageal Disease [CRED] & subsequent successful
symptomatic treatment with antacid. The possible
association between GERD & chronic laryngitis was
initially known as acid laryngitis .2
*from the Department of ENT, Hawlear Medical College, Hawlear university. Department of ENT, Rezgary Teaching Hospital, Erbil.
Correspondence to :
Dr.Said Mustafa Said
Corespondence Address to : Dr.Said Mustafa Said _ E- mail: Email [email protected] Mob. 07504563829
Recived at : 15 th Dec 2009 Accepted at : 3ed Nov 2010
OBJECTIVE: To record the common presentat
... Show MoreThis research paper looks to put its hands on sufi symbols which are applied by the algerian poet د abdallah hammadi د in his poetical works . the symbols it relies on are : ( symbolisme of wine . symbolisme of light . symbolisme of night . sufisme and nature , femal symbols ) .
From these symbols we try to show its range of ability to apply it , with trying to determine its meaningful , dimensions .
New derivatives of the anti-inflammatory, leprostatic drug dapsone 4 are synthesized, characterized and biologically screened by the treating the drug dapsone with chloroacetyl chloride in the presence of base. Both amino groups are acylated to give compound 6. The symmetrical acylated product then treated with Phenol, N-Acetyl-p-aminophenol, p-Chlorophenol, m-Chlorophenol, o-Hydroxybezoic acid and m-Hydroxybezoic acid to give compounds 8(a-f). The antimicrobial activity was tested for the synthesized compounds; activates were good compared to the parent drug. All the new compounds have scanned for their biological activities toward gram ‒ve and gram +ve (M. tuberculosis, S. pneumoniae, E. coli and P. mirabilis) bacteria, the synthesized
... Show MoreIn this paper, we define a cubic bipolar subalgebra, $BCK$-ideal and $Q$-ideal of a $Q$-algebra, and obtain some of their properties and give some examples. Also we define a cubic bipolar fuzzy point, cubic bipolar fuzzy topology, cubic bipolar fuzzy base and for each concept obtained some of its properties.
Abstract:
The Iraqi economy faces complex economic challenges that threaten the prospects for growth and stability in the short and medium term, The decrease in oil revenues on which Iraq is based in financing its total expenditure, both operational and investment, led to the emergence of a deficit in the government budget, As the global oil price crisis affected the revenues of the Iraqi government negatively, especially as this negative impact coincided with the increase in military spending resulting from Iraq's war against terrorism, Which led to the Iraqi government to implement austerity measures were to reduce public spending on several projects, which are less important compared to projects that a
... Show MoreBackground: diagnostic radiology field workers are at elevated risk level for systemic and oral diseases like periodontal diseases. This study was aimed to estimate the periodontal condition and salivary flow rate among diagnostic radiology workers. Material and method: The sample for this study consisted of a study group radiographers (forty subjects) working for 5 years at least and control group consisted of nurses and laboratory workers away from radiation (forty subjects) in Baghdad hospitals. All the 80 subjects aged 30-40 year-old and looking healthy without systemic diseases. Plaque, gingival, periodontal pocket depth and clinical attachment loss indices were used for recording the periodontal conditions. Under standardized condi
... Show MoreThis study aims to studying of Person and organization’s environment fit in a sample of Private bank’s reflection in its basic dimensions (Person-organization fit ,Person-Job fit, Person-group fit and Person- Person-fit )in the Work Outcomes (job satisfaction, the intention to leave the job, Job Engagement, and organizational citizenship behavior ).
The questionnair’e has been used as a basic instrument to gather data , As well as personal interviews with some of the staff of the research sample of private banks which were represented by (5) and included banks (Bank of Assyria for investment, the North Bank for Finance and Investment , Bank of the Tigris
... Show MoreRequires economic work finding built institutional paint strategies and policies are formulated general economic and clarity in its stated objectives and the involvement of all economic institutions, political and stakeholders to discuss all the issues of economic, financial, monetary and analyzed for the purpose of renewal energies and determine the duties and responsibilities, leaving full freedom to the private sector in the formation of institutions to carry out his duties economic, and that the institutional structures to create the right climate for the implementation of its economic policies, which would facilitate the task of the private sector, and this h
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