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91.
92.
New algorithms for searching simultaneously for a set of patterns in a text are suggested, for the special case where these patterns are correlated and have a common substring. This is then extended to the case where it could be more profitable to look for more than a single overlap, and a problem related to the generalization of this idea is shown to be NP-complete. Experimental results suggest that for this particular application, the suggested algorithm yields significant improvements over previous methods. 相似文献
93.
Eliahu Cohen Yair Avny Albert Zilkha 《Journal of polymer science. Part A, Polymer chemistry》1971,9(6):1469-1479
The anionic graft polymerization of propylene sulfide on cellulose membrane was studied. Alkali cellulosates were used to initiate graft polymerization, and graft polymers of high polypropylene sulfide content were obtained in good yields. The graft polymerization was accompanied by a certain extent of homopolymerization. The effects of reaction solvent, monomer concentration, cellulosate degree of substitution, and type of the alkali metal cellulosate on the graft polymer composition, yield, and on the molecular weight of the grafted side chains were investigated. 相似文献
94.
The iterative method of Cimmino for solving linear equations is generalized to linear inequalities. We also present a Richardson-type iterative method for solving the inequality problem, which includes the generalized Cimmino scheme. Convergence proofs are provided. 相似文献
95.
Yair E. Gath I. 《Proceedings of the IEEE. Institute of Electrical and Electronics Engineers》1988,76(9):1166-1175
A point process model of the speech excitation wave for sustained vowels has been formulated, where the pitch is modulated by a physiological disturbance (vocal tremor). It has been demonstrated that the power spectrum of an impulse train, representing the glottal pulses, is composed of a periodic replication of the spectrum of the modulating signal, accompanied by an impulse train at the carrier frequency. Hence, the power spectrum of the vocal tremor can be estimated from the pitch. A trend location algorithm has been developed to locate and remove local trends from the signal prior to the evaluation of the pitch power spectrum. Thus, spectral representation of the speech excitation enables estimation of vocal tremor 相似文献
96.
Eliahu Cohen Yair Avny Albert Zilkha 《Journal of polymer science. Part A, Polymer chemistry》1971,9(6):1481-1492
The adsorption of iodine, silver nitrate, and mercuric chloride by cellulosic membranes grafted with polypropylene sulfide was investigated. It was found that the grafted polypropylene sulfide adsorbed iodine by complexation from aqueous solution or from gaseous phase. Adsorption from water led to the formation of a complex with molar ratio of I2 to propylene sulfide units of 1, and that while the complex formed from gaseous iodine had a molar ratio I2 to propylene sulfide approaching 2. Most of the sulfide groups participated in complexation. It was found that the complexation of the polysulfide was accompanied by degradation which was attributed to halogenation of the polysulfide at the tertiary carbon atoms. The iodine complex was more stable in water than in organic solvents, where most of the iodine was desorbed. The graft polymers adsorbed also by complexation silver nitrate and mercuric chloride. Adsorption could be described by a Freundlich type isotherm. At low concentrations most of the silver nitrate present in solution was adsorbed. 相似文献
97.
Jonathan Tzadikov Natasha Ronith Levy Liel Abisdris Reut Cohen Michal Weitman Ilia Kaminker Amir Goldbourt Yair Ein‐Eli Menny Shalom 《Advanced functional materials》2020,30(19)
The fabrication of sulfur‐containing carbonaceous anode materials (CS) that show exceptional activity as anode material in Na‐ions batteries is reported. To do so, a general and straightforward bottom‐up synthesis of CS materials with precise control over the sulfur content and functionality is introduced. The new synthetic path combined with a detailed structural analysis and electrochemical studies provide correlations between i) the sulfur content and chemical species and ii) the structural, electronic, and electrochemical performance of the associated materials. As a result, the new CS substances demonstrate excellent activity as Na‐ion battery anode materials, reaching capacity values above 500 mAh g?1 at a current density of 0.1 A g?1, as well as high reversible sodium storage capabilities and excellent cycling durability. The results reveal the underlying working principles of carbonaceous materials, alongside the storage mechanism of the Na+ ions in these advanced sodium‐ion battery anode materials and provide a new avenue for their practical realization. 相似文献
98.
Every partially ordered set P on at least (1+o(1))n
3 elements can be decomposed into subposets of size n that are almost chains or antichains. This lower bound on P is asymptotically best possible. Similar results are presented for other types of combinatorial structures.Research supported in part by the AKA Research Fund of the Hungarian Academy of Sciences, grant 1-3-86-264. 相似文献
99.
In the present study, the changeover from the Pico.Tag HPLC method to the AccQ.Tag(ultra) UPLC method for the analysis of amino acids in casein and bovine serum albumine hydrolysates is described. The total chromatographic run time of the AccQ.Tag(ultra) UPLC method was only 40% of the time required for the Pico.Tag HPLC method. Quantitative results of both methods for casein and bovine serum albumine hydrolysates compared fairly well. The derivatisation protocol for the formation of AQC derivatives of amino acids was automated using a Gilson Model 215 liquid handler. Comparison of the manual derivatisation protocol with the automated protocol showed lower coefficients of variation for the latter. Combination of the AccQ.Tag(ultra) UPLC method and automated derivatisation resulted in improved throughput compared to the Pico.Tag HPLC method. 相似文献
100.
The problem considered in this paper is that of finding a point which iscommon to almost all the members of a measurable family of closed convexsubsets of R++
n
, provided that such a point exists.The main results show that this problem can be solved by an iterative methodessentially based on averaging at each step the Bregman projections withrespect to f(x)=i=1
nxi· ln xi ofthe current iterate onto the given sets. 相似文献