2,634 research outputs found
A Distributed Scheduling Algorithm to Provide Quality-of-Service in Multihop Wireless Networks
Control of multihop Wireless networks in a distributed manner while providing
end-to-end delay requirements for different flows, is a challenging problem.
Using the notions of Draining Time and Discrete Review from the theory of fluid
limits of queues, an algorithm that meets delay requirements to various flows
in a network is constructed. The algorithm involves an optimization which is
implemented in a cyclic distributed manner across nodes by using the technique
of iterative gradient ascent, with minimal information exchange between nodes.
The algorithm uses time varying weights to give priority to flows. The
performance of the algorithm is studied in a network with interference modelled
by independent sets
p-toluene sulfonic acid doped polyaniline carbon nanotube composites: synthesis via different routes and modified properties
Composites of polyaniline and carbon nanotube (CNT) were prepared by in-situ chemical polymerization method using various aniline concentrations in the initial polymerization solution with p-toluene sulfonic acid (PTS) as secondary dopant and mechanical mixing of the PANI and CNT using different weight ratios of PANI and CNTs. The structural characterizations of the composites were done by Fourier transform infrared (FTIR) and Ultra violet visible spectroscopy (UV-Visible). Scanning electron microscopy (SEM) was used to characterize the surface morphology of the composites. It was found that the composites prepared by in-situ chemical polymerization had smoother surface morphology in comparison to the composites obtained by mechanical mixing. The capacitive studies reveal that the in-situ composite has synergistic effect and the specific capacitance of the composite calculated from cyclic voltammogram (CV) was 385.1 F/g. Thermal studies indicate that the composites are stable as compared to PANI alone showing that the CNT contributes towards thermal stability in the PANI-CNT composites
Polymerization Of Methane
Plasma polymerization of methane in a magnetically enhanced capacitively coupled bell jar reactor operating at a frequency of 10 kHz is reported. Dependence of polymer deposition rate on monomer feed rate (F), composite power parameter (W/FM), electrode temperature, and electrode cleanliness have been examined. Such functional properties as wettability, adhesion, and thermal stability of the polymer are found to depend on the composite power parameter (W/FM) of the plasma. The permeability studies indicate highly crosslinked nature of the polymer. ESCA studies reveal code position of electrode material with the polymer under high W/FM conditions, potential applications of plasma polymer of methane are suggested. Copyright © 1989 John Wiley & Sons, Inc
Plasma Polymerization Of Tetramethyldisiloxane By A Magnetron Glow Discharge
Plasma polymerization of tetramethyldisiloxane by a magnetron glow discharge was studied. The glow discharge was created between parallel electrodes with a 10 kHz electric power source with a superimposed magnetic field using permanent bar magnets. Polymers were deposited onto moving substrates placed on the surface of a rotating disc located in between the electrodes. The deposition rates were determined with a quartz crystal thickness monitor placed on the plane of the rotating disc and just outside the edge of the disc. The current-voltage relationship observed for plasma polymerization of the monomer depends on the monomer feed rate and the conditioning of the electrodes or the establishment of a steady state surface in the polymer-forming plasma, which also depends mainly on the monomer feed rate. Consequently, plasma polymerization cannot be correlated to single operational parameters such as the discharge current, the power or the monomer feed rate in a simple manner. However, when the deposition rate was expressed as Rp/FM, where Rp is the polymer deposition rate, F is the monomer feed rate and M is the molecular weight (FM is thus the monomer mass feed rate), it was found that Rp/FM is uniquely related to the parameter W/FM where W is the discharge power in Watts. It was shown that many polymer properties were also determined mainly by the same composite parameter. It was also found that the presence of O2 gas in the monomer feed reduced the carbon content in the polymer and made the surface more hydrophobic while O2 plasma treatment of the plasma polymer rendered the surface more hydrophilic. © 1983
ProInflam: a webserver for the prediction of proinflammatory antigenicity of peptides and proteins
Additional file 2: Table S2. Dipeptide composition distribution between proinflammatory and non proinflammatory data
Evaluation of High Performance Converters Under Low Dose Rate Total Ionizing Dose (TID) Testing for NASA Programs
This paper reports the results of low dose rate (0.01-0.18 rads(Si)/sec) total ionizing dose (TID) tests performed on several types of high performance converters. The parts used in this evaluation represented devices such as a high speed flash converter, a 16-bit ADC and a voltage-to-frequency converter
- …