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91.
This paper investigates the effects of Walsh code selection and baseband filtering on the statistical moments of the band-limited forward-link CDMA signal. A normalized moment, the “power variance,” is proposed as a measure of the signal's sensitivity to nonlinear amplification. The estimation of the power variance for the case of a band-limited QPSK-modulated random waveform is presented as a baseline fur illustrating the effect of filtering on a sampled signal. The band-limited CDMA signal case illustrates the interaction between the Walsh codes and the wave-shaping filter, and quantifies the influence of “missing Hadamard basis functions. ”Results verify the accuracy of the statistical models and illustrate the importance of Walsh code selection in the reduction of the power variance of a band-limited CDMA waveform 相似文献
92.
93.
Lambert Nathaniel M.; Fincham Frank D.; Braithwaite Scott R.; Graham Steven M.; Beach Steven R. H. 《Canadian Metallurgical Quarterly》2009,1(3):139
The objective of these studies was to determine the strength and direction of the relationship between prayer and gratitude. In Study 1 (n = 674), the authors replicated the cross-sectional association between prayer frequency and gratitude that has been demonstrated in previous research. In Study 2 (n = 780), prayer frequency predicted gratitude 6 weeks later even when controlling for initial gratitude and religiosity. In Study 3 (n = 832), the authors replicated this longitudinal relationship, this time also controlling for socially desirable responding. In Study 4 (n = 104), participants were randomly assigned to prayer versus other conditions in a journal study that spanned 4 weeks. At follow up, those who were randomly assigned to pray every day reported higher gratitude scores than control participants. Together, these studies provide evidence that prayer increases gratitude. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
94.
Jung-Suk Goo Qi Xiang Takamura Y. Haihong Wang Pan J. Arasnia F. Paton E.N. Besser P. Sidorov M.V. Adem E. Lochtefeld A. Braithwaite G. Currie M.T. Hammond R. Bulsara M.T. Ming-Ren Lin 《Electron Device Letters, IEEE》2003,24(5):351-353
Strained-Si nMOSFETs with a standard polysilicon gate process were fabricated down to 25 nm gate length with well-behaved characteristics and small difference in short channel effects. The performance enhancement degrades linearly as the gate length becomes shorter, due to not only the parasitic resistance but also heavy halo implant. Thus the key integration issues are how to manage threshold difference and As diffusion without excess doping. With comparable doping and well controlled parasitic resistance, up to 45% improvement in drive current is predicted for sub-50 nm gate length strained-Si nMOSFETs on the Si/sub 0.8/Ge/sub 0.2/ substrate. In this work approximately 45% enhancement is in fact demonstrated for 35 nm gate length devices, through advanced channel engineering and implementation of metal gates. 相似文献
95.
J.G. Daugman's (1988) neural network solution to the Gabor expansion of an image is reformulated as a steepest descent implementation. Nonlinear optimization theory is then applied to select an appropriate convergence factor. Two quasi-Newton-based nonlinear optimization techniques are applied to improve the convergence for certain types of lattice. 相似文献
96.
Stanley S Percival CJ Auer M Braithwaite A Newton MI McHale G Hayes W 《Analytical chemistry》2003,75(7):1573-1577
A chemically coated piezoelectric sensor has been developed for the determination of PAHs in the liquid phase. An organic monolayer attached to the surface of a gold electrode of a quartz crystal microbalance (QCM) via a covalent thiol-gold link complete with an ionically bound recognition element has been produced. This study has employed the PAH derivative 9-anthracene carboxylic acid which, once bound to the alkane thiol, functions as the recognition element. Binding of anthracene via pi-pi interaction has been observed as a frequency shift in the QCM with a detectability of the target analyte of 2 ppb and a response range of 0-50 ppb. The relative response of the sensor altered for different PAHs despite pi-pi interaction being the sole communication between recognition element and analyte. It is envisaged that such a sensor could be employed in the identification of key marker compounds and, as such, give an indication of total PAH flux in the environment. 相似文献
97.
W.J. Braithwaite 《Computer Physics Communications》1973,5(5):390-394
Title of program : LEGENDRE Catalogue : ABME Program obtainable from : CPC Program Library, Queen's University of Belfast, N. Ireland (see application form in this issue). Computer : CDC 6600; Installation : University of Texas, Austin, Texas, USA Operating system : CDC Scope Programming language used : FORTRAN IV High speed storage required : 4928 words. No. of bits in a word : 60 Is the program overlaid? No No. of magnetic tapes required : None What other peripherals are used? Card reader, line printer No. of cards in combined program and test deck : 160 Card punching code : CDC 相似文献
98.
Lauer I. Langdo T.A. Cheng Z.-Y. Fiorenza J.G. Braithwaite G. Currie M.T. Leitz C.W. Lochtefeld A. Badawi H. Bulsara M.T. Somerville M. Antoniadis D.A. 《Electron Device Letters, IEEE》2004,25(2):83-85
Strained silicon-on-insulator (SSOI) is a new material system that combines the carrier transport advantages of strained Si with the reduced parasitic capacitance and improved MOSFET scalability of thin-film SOI. We demonstrate fabrication of highly uniform SiGe-free SSOI wafers with 20% Ge equivalent strain and report fully depleted n-MOSFET results. We show that enhanced mobility is maintained in strained Si films transferred directly to SiO/sub 2/ from relaxed Si/sub 0.8/Ge/sub 0.2/ virtual substrates, even after a generous MOSFET fabrication thermal budget. Further, we find the usable strained-Si thickness of SSOI significantly exceeds the critical thickness of strained Si/SiGe without deleterious leakage current effects typically associated with exceeding this limit. 相似文献
99.
KL Braithwaite T Barna TD Spurway SJ Charnock GW Black N Hughes JH Lakey R Virden GP Hazlewood B Henrissat HJ Gilbert 《Canadian Metallurgical Quarterly》1997,36(49):15489-15500
A genomic library of Pseudomonas fluorescens subsp. cellulosa DNA was screened for galactanase-positive recombinants. The nine galactanase positive phage isolated contained the same galactanase gene designated galA. The deduced primary structure of the enzyme (galactanase A; GalA) encoded by galA had a Mr of 42 130 and exhibited significant sequence identity with a galactanase from Aspergillus aculeatus, placing GalA in glycosyl hydrolase family 53. The enzyme displayed properties typical of an endo-beta1, 4-galactanase and exhibited no activity against the other plant structural polysaccharides evaluated. Analysis of the stereochemical course of 2,4-dinitrophenyl-beta-galactobioside (2,4-DNPG2) hydrolysis by GalA indicated that the galactanase catalyzes the hydrolysis of glycosidic bonds by a double displacement general acid-base mechanism. Hydrophobic cluster analysis (HCA) suggested that family 53 enzymes are related to the GH-A clan of glycosyl hydrolases, which have an (alpha/beta)8 barrel structure. HCA also predicted that E161 and E270 were the acid-base and nucleophilic residues, respectively. Mutants of GalA in which E161 and E270 had been replaced with alanine residues were essentially inactive against galactan. Against 2,4-DNPG2, E161A exhibited a much lower Km and kcat than native GalA, while E270A was inactive against the substrate. Analysis of the pre-steady-state kinetics of 2,4-DNPG2 hydrolysis by E161A showed that there was an initial rapid release of 2,4-dinitrophenol (2,4-DNP), which then decayed to a slow steady-state rate of product formation. No pre-steady-state burst of 2,4-DNP release was observed with the wild-type enzyme. These data are consistent with the HCA prediction that E161 and E270 are the acid-base and nucleophilic catalytic residues of GalA, respectively. 相似文献
100.
A. K. Altunoglu N.St J. Braithwaite 《Metallurgical and Materials Transactions A》1996,27(9):2495-2503
A series of modulated permeation experiments have been performed on foils of cold-worked nickel and nickel thoria (NITD).
The parameters of the measurements include modulation frequency and base pressure together with the thickness, specimen temperature,
and pretreatment of the foil. Experiments were carried out between 373 and 920 K. The frequency response of the permeation
flux shows a characteristic form which has been modeled satisfactorily. Permeation and trapping data are derived from the
fitting of the model to experimental characteristics. The degree of trapping dimin-ishes as the extent of the annealing increases,
and as the base pressure (driving) increases, the degree of trapping decreases. These effects suggest that the trapping sites
had been introduced by cold working, but that they are not directly associated with accumulation of hydrogen gas in the micro-voids.
It is suggested that dislocation networks formed around thoria particles are responsible for the trapping of hydrogen in NITD
with a depth of 40 kJ/mole. Trapping has also been detected for cold-worked nickel, at much lower temperatures than in NITD.
Transmission electron microscopy (TEM) studies have also been correlated with measurements of hardness and resistivity to
monitor the annealing process. 相似文献