Passive optical network (PON) is a point to multipoint, bidirectional, high rate optical network for data communication. Different standards of PONs are being implemented, first of all PON was ATM PON (APON) which evolved in Broadband PON (BPON). The two major types are Ethernet PON (EPON) and Gigabit passive optical network (GPON). PON with these different standards is called xPON. To have an efficient performance for the last two standards of PON, some important issues will considered. In our work we will integrate a network with different queuing models such M/M/1 and M/M/m model. After analyzing IPACT as a DBA scheme for this integrated network, we modulate cycle time, traffic load, throughput, utilization and overall delay mathematically for single OLT and multiOLT EPON system, and average delay and throughput for single OLT GPON system. A comparison of average delay and throughput between EPON and GPON is introduced with the same number of ONUs. The results show that the proposed multi-OLT EPON system can supports existing bandwidth allocation schemes with better performance than the single-OLT EPON. Cycle delay and average delay is decreased with multi-OLT system than in single OLT system, while throughput of multi-OLT system is higher than throughput of single OLT system. Splitting ratio and throughput in GPON is much higher than in EPON.
: zonal are included in phraseological units, form metaphorical names for a person, give him various emotional and evaluative characteristics. This article examines the topic of zoomorphic metaphors that characterize a person in the Russian and Arabic languages in the aspect of their comparative analysis, since the comparative analysis of the metaphorical meanings of animalisms is an important method for studying cultural linguistics, since zoomorphic metaphors are a reflection of culture in a language.
تعد الموازنة الأداة الأساسية لتنفيذ أولويات أية دولة، ويتوجب النظر إليها في ضوء المناخ الاجتماعي والسياسي والاقتصادي، لأنها تساعد في توجيه الاقتصاد لتحقيق النمو ورفع مستوى الرفاهية. اعتمدت وزارة المالية في أعداد الموازنة السنوية بعد 9/4/ 2003 أسلوباً مغايراً لما كان معتمداً في العقود الماضية، إذ كانت هناك موازنتين الأولى الموازنة الجارية، والثانية الموازنة الاستثمارية رغم وجود قانون يحتم إصدار موازنة
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The fatty acids in the embryo's liver at ages (7, 11, 14 and 19) days incubation, small chicken aged (14) days after hatching and adult were analyzed, and found (5) fatty acids, the highest concentration of fatty acid in the adult of domesticated chicken and lowest concentration in small chicken age (14) days after hatching. Statistically, there were high significant differences at the probability level (P≤0.001) between all ages together, and the highest concentrations of Oleic acid (C18:1) and Linoleic acid (C18:2) were in embryo age (7) days incubation, while in embryo age (11) days incubation Stearic acid (C18:0) and α-Linolenic acid (C18:3) were higher concentration and Palmitic acid (C16:0) was the highest concentration in the adul
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Fe3O4:Ce thin films were deposited on glass and Si substrates by Pulse Laser Deposition Technique (PLD). Polycrystalline nature of the cubic structure with the preferred orientation of (311) are proved by X-ray diffraction. The nano size of the prepared films are revealed by SEM measurement. Undoped Iron oxide and doped with different concentration of Ce films have direct allowed transition band gap with 2.15±0.1 eV which is confirmed by PL Photoluminescence measurements. The PL spectra consist of the emission band located at two sets of peaks, set (A) at 579±2 nm , and set (B) at 650 nm, respectively when it is excited at an excitation wavelength of 280 nm at room temperature. I-V characteristics have been studied in the dark and under v
... Show MoreComparative Analysis of Economic Policy Stability between Monarchical and Republican Systems: A Theoretical Fundamental Research
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Hashimoto Thyroiditis (HT) is the most common autoimmune thyroid disease and the commonest cause ofhypothyroidism. C-reactive protein (CRP) is synthesized in hepatocyte in response to autoimmune disorders;strongly induced by IL-6. This study aimed to estimate serum IL-6 and CRP levels in autoimmune and non-autoimmune hypothyroidism. The present study included 60 Iraqi female hypothyroid patients divided to 30autoimmune and 30 non-autoimmune, with age ranged between 24-50 years and 30 healthy controls withage ranged between 27-52 years. Serum samples were collected from study groups. The levels of thyroidhormones (TSH, T4 and T3) were determined by using automated Chemiluminescence Immunoassay (CLIA)analysis system. Detection the levels of t
... Show MoreA numerical study of the double-diffusive laminar natural convection in a right triangular solar collector has been investigated in present work. The base (absorber) and glass cover of the collector are isothermal and isoconcentration surfaces, while the vertical wall is considered adiabatic and impermeable. Both aiding and opposing buoyancy forces have been studied. Governing equations in vorticity-stream function form are discretized via finite-difference method and are solved numerically by iterative successive under relaxation (SUR) technique. Computer code for MATLAB software has been developed and written to solve mathematical model. Results in the form of streamlines, isotherms, isoconcentration, average Nusselt, and average Sherw
... Show MoreBackground: Hyperthyroidism occurs due to over production of thyroid hormones, one types of hyperthyroidism was Graves, disease. Hyperthyroidism is characterized by high level of serum thyroxin, triiodothyronine and low level of thyroid stimulated hormones. Material and Methods: fifty two hyperthyroid patients, thirty patients under treatment with carbimazole and other twenty two patients under treatment with radioactive iodine, and sixty healthy control group. The average salivary flow rate was calculated as ml/5mint.The concentration of calcium, potassium, and total protein were determined in the salivary supernatant sample. This is done through different biochemical tests. Determination of salivary IgA is done by ELIZA. Results: The most
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