Multimedia applications impose different QoS requirements (e.g., bounded end-to-end delay and jitter) and need an enhanced transport layer protocol that should handle packet loss, minimize errors, manage network congestion, and transmit efficiently. Across an IP network, the transport layer protocol provides data transmission and affects the QoS provided to the application on hand. The most common transport layer protocols used by Internet applications are TCP and UDP. There are also advanced transport layer protocols such as DCCP and TFRC. The authors evaluated the performance of UDP, DCCP, SCTP, and TFRC over wired networks for three traffic flows: data transmission, video streaming, and voice over IP. The evaluation criteria were throughput, end-to-end delay, and packet loss ratio. They compared their performance to learn in which traffic flow/service each of these protocols functions better than the others. The throughput of SCTP and TFRC is better than UDP. DCCP is superior to SCTP and TFRC in terms of end-to-end delay. SCTP is suitable for Internet applications that require high bandwidth.
Supernova explosions are described as very violent events which transfer a significant amount of energy to interstellar media and are responsible for a large variety of physical processes. This study does not discuss the actual explosion mechanisms but follows the behavior of the dynamical evolution of some selected type I and type II supernova remnant and particularly after a thousand years from their explosion and shows how the density of the medium affects the evolution and the lifetime of each remnant. By studying such behaviors, a simplified model has been proposed here for the velocity and radius of the remnant after thousand years of explosion that depends only on the density of the medium and age of the remnant. It has been found th
... Show MoreThe research problem is dedicated to investigate reservoirs irrational economic behavior adopted by the ruling elites in developing countries about the investment methodology of human capital and operating policies is based on the terms of reference of economic theory and standards governing the market, which led to a chronic structural imbalance in the workforce structure and lack of consistency with different production structure, in turn, which had a reported effects in the emergence of the phenomenon of unemployment and that they involved a certain privacy, as has become the issues of unemployment and employment in the various countries of the world are issues more important due to the presence of large numbers of the workforce in th
... Show MoreAmino acids have the role in the process of proteins synthesis. They are an essential source of nitrogen atoms that have a role in the pathways of synthetic reaction pathways. The carbon skeletons of the amino acids are the source of energy in addition to their role as precursors in the paths of interactions. The amino acids analysis for the brain of the quail bird in different stage of development (10-16 days of incubation) in addition to the hatching stage (17th day) and the adult. Materials and Methods: Amino Acids Analysis The amino acids were separated from the embryos and adult brains of the quail bird Coturnix coturnix and were diagnosed based on standard amino acids, using high performance liquid chromatographic device (H.P.L.C.). R
... Show MorePolyaniline membranes of aniline were produced using an electrochemical method in a cell consisting of two poles. The effect of the vaccination was observed on the color of membranes of polyaniline, where analysis as of blue to olive green paints. The sanction of PANI was done by FT-IR and Raman techniques. The crystallinity of the models was studied by X-ray diffraction technique. The different electronic transitions of the PANI were determined by UV-VIS spectroscopy. The electrical conductivity of the manufactured samples was measured by using the four-probe technique at room temperature. Morphological studies have been determined by Atomic force microscopy (AFM). The structural studies have been measured by (SEM).
Age, hypertension, and diabetes can cause significant alterations in arterial structure and function, including changes in lumen diameter (LD), intimal-medial thickness (IMT), flow velocities, and arterial compliance. These are also considered risk markers of atherosclerosis and cerebrovascular disease. A difference between right and left carotid artery blood flow and IMT has been reported by some researchers, and a difference in the incidence of nonlacunar stroke has been reported between the right and left brain hemispheres. The aim of this study was to determine whether there are differences between the right and left common carotid arteries and internal carotid arteries in patient
Amino and fatty acids in the liver tissue of Uromastyx aegyptius microlepis during the periods of hibernation (December) and activity (May) were estimate by a high performance liquid chromatography, liver of a lizard during the activity and hibernation seasons, contained 18 amino acids, which include, 10 essential amino acids and 8 non-essential amino acids, and the liver in the male lizard contained five fatty acids during each season, the concentration rates of all the amino acids during the activity season were higher than their counterparts during the hibernation season, the total concentrations of essential and non-essential amino acids during the activity season were 19434.8 µg/ml, which was greater than the total concentrations leve
... Show MoreThe effect of the aqueous extract of fenugreek seeds (Trigonella Foenum Graecum L.), Rhodium complex (?) with formula [RhL2CLH2O].1 1/2 ETOH and palladium (?) [pdl2].2ETOH,where L=2-hydroxy phenyl piperonalidine was studied on two cancer cell lines. The first cell line was intestine cancer of female albino mice (L20B), the second one was Rhabdomysarcomas (RD)cell line in human. The activity of the new complexes and the aqueous extract was compared to the well-known anticancer drug (cis-platin) by utilizing the in vitro system. The cell lines were treated with four concentrations of cis-platin 31.25,62.5,125 and 250 ?g/ml for 72 hour exposure time. The same concentrations were used with extract and the new complexes. This study showed that t
... Show MoreThe purpose of this paper is to preparing preventive exercises supported by collagen supplements and vitamin D for handball players, and identify the effect of preventive physical exercises supported by collagen supplements and vitamin D on some physical and skill abilities of handball players. The researchers used the experimental method and designed two groups, one experimental and the other control, with both pre- and post-tests, to suit the nature of the research. The research community was selected from handball players (specialized school players), numbering (14), and they were divided into two groups, each group numbering (7) players. One of the most important results reached by the researcher is that: The exercises prepared by the r
... Show MoreThis study presents a mathematical model describing the interaction of gut bacteria in the participation of probiotics and antibiotics, assuming that some good bacteria become harmful through mutations due to antibiotic exposure. The qualitative analysis exposes twelve equilibrium points, such as a good-bacteria equilibrium, a bad-bacteria equilibrium, and a coexisting endemic equilibrium in which both bacteria exist while being exposed to antibiotics. The theory of the Sotomayor theorem is applied to study the local bifurcation around all possible equilibrium points. It’s noticed that the transcritical and saddle-node bifurcation could occur near some of the system’s equilibrium points, while pitchfork bifurcation cannot be accrued at
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