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101.
Zain Shabbir Anas Razzaq Ghumman Shabbir Majeed Chaudhry 《Circuits, Systems, and Signal Processing》2016,35(9):3113-3134
A low-power, high-speed \(4\times 4\) multiplier using Dadda algorithm is proposed. The full adder blocks used in this multiplier have been designed using reduced-split precharge-data driven dynamic sum logic. Flip flops used in the pipeline registers have been designed to increase input signal noise margin, resulting in the minimization of output signal glitches. The multiplier circuit is implemented in 1P-9M Low-K UMC 90nm CMOS process technology. Post-layout simulations are carried out using Cadence Virtuoso. The proposed multiplier operates at a clock frequency of 3.5 GHz, with an average dynamic power consumption of 1.096 mW at a temperature of \(27\,^{\circ }\hbox {C}\) and 1 V supply voltage and occupies a chip area of \(76\,\upmu \hbox {m}\times 102\,\upmu \hbox {m}\). 相似文献
102.
103.
Joseph H. Banoub Anas El Aneed Alejandro M. Cohen Nicolas Joly 《Mass spectrometry reviews》2010,29(4):606-650
Mass spectrometric studies are now playing a leading role in the elucidation of lipopolysaccharide (LPS) structures through the characterization of antigenic polysaccharides, core oligosaccharides and lipid A components including LPS genetic modifications. The conventional MS and MS/MS analyses together with CID fragmentation provide additional structural information complementary to the previous analytical experiments, and thus contribute to an integrated strategy for the simultaneous characterization and correct sequencing of the carbohydrate moiety. © 2010 Wiley Periodicals, Inc., Mass Spec Rev 29:606–650, 2010 相似文献
104.
The transient liquid phase (TLP) bonding of Ti-6Al-4V alloy to a Mg-AZ31 alloy was performed using an electrodeposited Ni coating containing a dispersion of Ni and Cu nanoparticles. Bond formation was attributed to two mechanisms; first, solid-state diffusion of Ni and Mg, followed by liquid eutectic formation at the Mg-AZ31 interface. Second, the solid-state diffusion of Ni and Ti at the Ti-6Al-4V interface resulted in a metallurgical joint. The joint interface was characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, and X-ray diffraction analysis. Microhardness and shear strength tests were used to investigate the mechanical properties of the bonds. The use of Cu nanoparticles as a dispersion produced the maximum joint shear strength of 69 MPa. This shear strength value corresponded to a 15 % enhancement in joint strength compared to TLP bonds made without the use of nanoparticles dispersion. 相似文献
105.
Omar A. Saraereh Qais Alsafasfeh Anas Al Tarabsheh Aouda Arfoa Issa Etier 《能源与动力工程:英文版》2014,(3):560-567
Power systems are the largest and most complex human made systems, consisting of thousands of electrical sources, loads, transmission and distribution lines, power transformers, circuit breakers, etc. where faults always occurred. Faults can cause personnel and equipment safety problems, and can result in significant disruption to power supply and thus financial losses. In this paper we will present comprehensive mathematical suite to detect and classify fault dependent models of various types of power systems. This work will extract fault unique signatures by using polarization ellipse during the healthy condition and the polarization will be circular shape with radius equal the rated voltage of the system, but during the fault condition the polarization will be ellipse shape and the fault signature will be defined according the ellipse parameters major axis, minor axis, ellipticity and orientation angle, by using least squares criterion will define the ellipse parameters this system will identify and classify. This paper will be a milestone for extended paper based on the proposed mathematical modelling and applying it to identify, classify and localize with simulation model. 相似文献
106.
Tareq M. Osaili Anas A. Al‐Nabulsi Amin N. Olaimat Reyad R. Shaker Mohammad Taha Richard A. Holley 《Journal of food science》2014,79(9):M1750-M1755
Escherichia coli O157:H7 is a major foodborne pathogen that causes severe disease in humans. Survival of E. coli O157:H7 during processing and storage of white brined cheese was investigated. Cheeses were prepared using pasteurized milk inoculated with a 4 strain E. coli O157:H7 cocktail (7 log10 CFU/g) with or without yogurt starter culture (Lactobacillus delbrueckii ssp. bulgaricus and Streptococcus salivarius ssp. thermophilus) and stored in 10% or 15% NaCl brine at 10 and 21 ºC for 28 d. NaCl concentration, water activity (aw), pH, and numbers of E. coli O157:H7 and lactic acid bacteria (LAB) were determined in cheese and brine. E. coli O157:H7 was able to survive in cheese stored in both brines at 10 and 21 ºC regardless of the presence of starter LAB, although the latter significantly enhanced E. coli O157:H7 reduction in cheese or its brine at 10 ºC. E. coli O157:H7 numbers were reduced by 2.6 and 3.4 log10 CFU/g in cheese stored in 10% and 15% NaCl brine, respectively, in the presence of starter LAB and by 1.4 and 2.3 log10 CFU/g, respectively, in the absence of starter LAB at 10 ºC. The pathogen survived, but at lower numbers in the brines. The salt concentration of cheese stored in 10% brine remained about 5% during ripening, but in 15% brine, the NaCl level increased 1.6% to 8.1% (w/w) by 28 d. Values of pH and aw slightly decreased 1 d after exposure to brine and reached 5.5 to 6.6 and 0.88 to 0.94, respectively, in all treatments. 相似文献
107.
Aljemely Anas H. Xuan Jianping Xu Long Jawad Farqad K. J. Al-Azzawi Osama 《Applied Intelligence》2021,51(10):6932-6950
Applied Intelligence - Fault identification is a vital task to ensure the integrity and reliability of rotating machinery. The vibration signals produced by the defective system components... 相似文献
108.
The pyrolysis-catalytic steam reforming of six agricultural biomass waste samples as well as the three main components of biomass was investigated in a two stage fixed bed reactor. Pyrolysis of the biomass took place in the first stage followed by catalytic steam reforming of the evolved pyrolysis gases in the second stage catalytic reactor. The waste biomass samples were, rice husk, coconut shell, sugarcane bagasse, palm kernel shell, cotton stalk and wheat straw and the biomass components were, cellulose, hemicellulose (xylan) and lignin. The catalyst used for steam reforming was a 10 wt.% nickel-based alumina catalyst (NiAl2O3). In addition, the thermal decomposition characteristics of the biomass wastes and biomass components were also determined using thermogravimetric analysis (TGA). The TGA results showed distinct peaks for the individual biomass components, which were also evident in the biomass waste samples reflecting the existence of the main biomass components in the biomass wastes. The results for the two-stage pyrolysis-catalytic steam reforming showed that introduction of steam and catalyst into the pyrolysis-catalytic steam reforming process significantly increased gas yield and syngas production notably hydrogen. For instance, hydrogen composition increased from 6.62 to 25.35 mmol g?1 by introducing steam and catalyst into the pyrolysis-catalytic steam reforming of palm kernel shell. Lignin produced the most hydrogen compared to cellulose and hemicellulose at 25.25 mmol g?1. The highest residual char production was observed with lignin which produced about 45 wt.% char, more than twice that of cellulose and hemicellulose. 相似文献
109.
The authors demonstrate using both simulation and experiment, a drop code unit for metro ring optical networks with service differentiation capability. This is achieved by means of a spectral amplitude coding technique whereby the code weight in a particular channel is varied to provide different signal quality levels. Transmission of three channels with different weights operating at 10 Gbps per channel was simulated over a 68 km unamplified and 185 km amplified links of dispersion compensated fibre. Services are perfectly dropped at bit error rates from 10-9 to 10-3, leaving the through service free from accumulated noise. The authors also present a 2.5 Gbps per channel proof-of-concept experiment over 40 km of single-mode fibre (SMF). 相似文献
110.
Pyrolysis-catalysis of high density polyethylene (HPDE) was carried out in a fixed bed, two stage reactor for the production of upgraded aromatic pyrolysis oils. The catalysts investigated were Y-zeolite impregnated with transition metal promoters with 1 wt% and 5 wt% metal loading of Ni, Fe, Mo, Ga, Ru and Co to determine the influence on aromatic fuel composition. Pyrolysis of the HDPE took place at 600 °C in the first stage of the reactor system and the evolved pyrolysis gases were passed to the second stage catalytic reactor, which had been pre-heated to 600 °C. Loading of metals on the Y-zeolite catalyst led to a higher production of aromatic hydrocarbons in the product oil with greater concentration of single ring aromatic hydrocarbons produced. The single ring aromatic compounds consisted of mainly toluene, ethylbenzene and xylenes, while the 2-ring hydrocarbons were mainly naphthalene and their alkylated derivatives. There was a reduction in the production of multiple ring aromatic compounds such as, phenanthrene and pyrene. The addition of the promoter metals appeared to have only a small influence on aromatic oil content, but increased the hydrogen yield from the HDPE. However, there was significant carbon deposition on the catalysts in the range 14–22 wt% for the 1% metal-Y-zeolite catalysts and increased to 18–26 wt% for the 5 wt% metal-Y-zeolite catalysts. 相似文献