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Dynamic admission control & scheduling for efficient channel utilization in the networks.
No full textThe telecommunication world witnessed an exponential growth since the inception of Wireless cellular communication which the industry scrutinized in the mid-1980s, with the launch of the so-called 1G (first-generation) analogue technology like AMPS (Advanced Mobile Phone System) in USA or NMT (Nordic Mobile Telephone) in Northern Europe. These systems were then further engineered to 2G (second-generation) digital radio – attaining a better spectral efficiency and being more robust and, ultimately, to 3G (third-generation), so as to offer global mobility and improved end-user experience over a wide range of services. This idiosyncratic prosperity of wireless communication has a sound impact on global businesses, with the increasing demands for better spectral usage and low cost per bit taking into account the addition of Multi-media usage.
In regards to all these evolutionary demands set by the end user a system emerged known as EPS (Evolved Packet System) representing the very latest evolution of the UMTS standard. EPS is also known by other acronyms related to technical study items being worked on at 3GPP standard committees: LTE (Long Term Evolution), which is dedicated to the evolution of the radio interface, and SAE (System Architecture Evolution), which focuses on Core Network architecture evolution.
Wireless Channels incur different user capacities with time, provision of standard QoS might result in resource hungry system in terms of energy consumption and channel bandwidth utilization. In this research principal focus will be on investigating the downlink channel performance in terms of channel dependent scheduling and priority handling. Downlink Channel is shared by downlink data (PDSCH) and downlink control
(PDCCH) channels which if properly scheduled can result in freeing up a lot of channel space for downlink data and also considering admission control mechanism for priority handling eventually resulting in improved performance in terms of channel utilization. In this context, a dynamic admission control and scheduling algorithm is proposed that goes through a comprehensive perusal phase from system performance improvement and implementation complexity perspective in order to perform better than the current standard admission control and equal capacity shared scheduling approach in 3GPP Release 8
Virtual reality use in motor rehabilitation of neurological disorders: A Systematic Review
No full textRecent experimental evidence suggests that rapid advancement of virtual reality (VR) technologies has great potential for the development of novel strategies for motor rehabilitation. Virtual reality is a computer based, interactive, multi-sensory simulation environment that occurs in real time. The aim of this review was to discuss the rationale, criteria of application, limits of the available procedures and the effects of VR in the rehabilitation of patients with stroke and those with cerebral palsy (CP). Seventeen published articles from 1/1/2002 to 1/05/2010 were reviewed. Classification of the available virtual reality setups and comparison among published studies, with focus on the criteria of motor impairment and recovery assessment, rehabilitation procedures, and efficacy were reviewed. The studies completed to date support the application of VR in the treatment of patients after stroke and CP patients. The duration of the rehabilitation effects after discontinuing VR training is crucial and should be determined in controlled follow-up studies
New Validated Potentiometric Determination of Vasodilator Pentoxifylline
No full textThe construction and performance characteristics of pentoxifylline selective electrodes were developed.Two types of electrodes: plastic membrane I and coated wire II were constructed based on the incorporationof pentoxifylline with phosphotungstic acid (PTA). The influence of membrane composition,kind of plasticizer, pH of the test solution, soaking time, and foreign ions on the electrodes was investigated.The electrodes showed a Nernstain response with a mean calibration graph slope of 56.77 ± 0.19and 55.76 ± 0.71 mV decade-1 at 25 ºC for electrode I and II respectively, over pentoxifylline concentrationrange from 1.0 × 10-5-1.0 × 10-2 and 9.0 × 10-6-1.0 × 10-2mol L-1, with detection limits 4.89× 10-6 and3.90 × 10-6mol L-1 for electrode I and II, respectively. The pH range of the constructed electrodes was 4-6.
Interferences from common cations, alkaloids, sugars, amino acids and drug excipients were reported.The results obtained by the proposed electrodes were also applied successfully to the determination of thedrug in its pharmaceutical preparations and biological fluids.King Saud Universit
Development of structural and optical properties of WOx films upon increasing oxygen partial pressure during reactive sputtering
No full textWOx films were prepared by reactive dc magnetron sputtering using tungsten target. Sputtering was carried out at a total pressure of 1.2 Pa using a mixture of argon plus oxygen in an effort to determine the influence of the oxygen partial pressure on structural and optical properties of the films. The deposition rate decreases significantly as the surface of the target is oxidized. X-Ray diffraction revealed the amorphous nature of all the films prepared at oxygen partial pressures higher than 1.71×103 Pa. For higher oxygen partial pressures, fully transparent films were deposited, which showed a slight increase in optical band gap with increasing oxygen partial pressure, while the refractive index was simultaneously decreased
HYDRAULIC JUMPS PROPERTIES ON CORRUGATED BEDS
No full textAbstract Hydraulic jumps have been used for dissipation of kinetic energy downstream of hydraulic structures, such as spillways, chutes, and gates. It was found that if jumps were made to occur on corrugated beds, tail water and length of jumps reduced significantly. The effects of corrugations on the basic characteristics of jump were studied for a different range of Froude number from 3 to 7.5. Five shapes of corrugations (sinusoidal, triangular, trapezoidal with two side slopes and rectangular) of the same amplitude and wavelength were tested. Two values of relative roughness t/y1 of 0.36 and 0.72 were studied. It was found that, for all shapes of corrugated beds, the tailwater depth required to form a jump was appreciably smaller than that for the corresponding jumps on smooth beds. Further, the length of the jump on the different corrugated beds was less than half of that on smooth beds. For the same amplitude and wavelength, it was found that the effect of the shape of corrugations is relatively small. The results of this study confirm the effectiveness of corrugated beds for energy dissipation below hydraulic structures. Finally, attempts were made to draw some conclusions from this experimental study.Research Center, Faculty of Engineering, King Saud Universit
Fluidization of nano-powders: Effect of sound vibration and pre-mixing with group A particles
No full textBioreactors; Multiplicity; Operability; Oscillations; Singularit
Prediction of regime transitions in bubble columns using acoustic and differential pressure signals
No full textThis paper addresses the identification of the transition points of the flow regimes in bubble columns. For this purpose, statistical and spectral analysis of the acoustic sound signals and differential pressure signals were employed over several values of the gas velocity. Both analysis tools were able to extract useful qualitative and quantitative information about the flow patterns. In addition, applying the two methods to both types of signals presented comparable results about the quantitative values of the critical velocities. These values agree well with those reported in the literature. Moreover, the implementation of the auto-correlation function on the differential pressure signal was found helpful in determining period of the macro-structure fluctuation
TWO LEVEL DIGITAL CONTROL SYSTEM FOR SPEED AND GENERATION OF A MULTI-UNIT POWER STATION.
No full textWith the proposed system, the power station generating units can be operated in both the independent and joint control modes. Unit transfer between these two modes of operation, as commanded by higher levels, is performed without causing any disturbance to the power system. performance of the proposed system has been investigated using both digital simulation and practical laboratory implementation. In laboratory tests micro and mini-computer systems were used on-line to control the generating unit and the power station supervisory levels respectively
Molecular and Physiological Aspects for Lepidium sativum Tolerance in Response to Lead Toxicity.
No full textThe present study was undertaken to evaluate the toxicity of Pb2+ on photosynthetic pigments, total soluble protein and MDA contents as well as the activities of SOD, CAT and POD in Lepidium sativum leaves after 10-days of supplying Lead (0-600 ppm) in the nutrient solution. The results indicated that Lead treatment adversely affected plant growth and disturbed the cell metabolism critically. The development of toxic symptoms, corresponded to a high accumulation of Pb2+, was a sum to the increase in H2O2 and MDA contents, decrease in protein content, and the much elevated SOD and POD activities in leaves. In addition, the results demonstrated that exposure to high concentration of lead (Pb2+ > 400 ppm), could result the disintegration of antioxidant system in Lepidium seedlings. Also the significant decrease in the contents of photosynthetic pigments was related to high-level metal stress. Higher concentrations of Pb2+, especially 400 and 600 ppm, resulted in a great variation in protein pattern distribution. The outcome of this study corroborate that Lepidium sativum is a suitable hyper-accumulator candidate and tolerate against low-level lead contaminated soil
Detection of genetically modified rice: collaborative validation study of a PCR based detection of genetically modified rice Oryza sativa commercially available in Saudi Arabia.
No full textA collaborative trial study has been conducted for validation of an extraction method and a subsequent PCR for detection of transgenic rice sold in Saudi Arabia. The tests were carried out in Saudi Arabia using Real-Time PCR and the positive samples were validated in another lab in Malaysia using PCR and agarose gel visualization. The samples were tested for the existence of the NOS Terminator. A total of 150 samples were tested out of which three samples tested positive as GM-rice which were retested in Malaysia. The presence of GMO rice in Saudi Arabia supports the necessity of developing precise quantitative and qualitative ways for routine analyses and detection of GMO products in the Saudi Arabian market. With the discovery of GM products in the Saudi Arabian market it would be of no surprise that other Middle Eastern nations also knowingly or unknowingly import GM crops