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611.
Marek Markowski Katarzyna Majewska Dariusz Kwiatkowski Mateusz Malkowski Grzegorz Burdylo 《International Journal of Food Properties》2013,16(4):890-903
The properties of grain of Mauritia and Prestige barley varieties were determined for moisture content of 12.5 and 15.5% wet basis. Broad variations were observed in the relationship between the moisture content of grain, its variety, and the geometric properties of barley. Most of the geometric properties of barley were dependent on both the cultivar studied and the moisture content of grain, while selected characteristics were dependent on moisture content of grain or barley cultivar only. The values of displacement, force and energy required for kernel rapture were lower for Mauritia variety than Prestige variety and were not dependent on the moisture content of grain. 相似文献
612.
Joanna Raczkowska Grzegorz Mielcarz Alan Howard Michał Raczkowski 《International Journal of Food Properties》2013,16(3):514-522
Ultra performance liquid chromatography–photodiode array detection (UPLC–PDA) was used to analyze five biologically active polyphenolic compounds (catechin, epicatechin, rutin, trans-resveratrol, and quercetin) in different types of wine available in the Polish market. The results showed that the major polyphenols in chosen wines were catechin and epicatechin, the minor polyphenol was trans-resveratrol. The use of UPLC system allowed a shorter run time of up to six times in comparison with the conventional HPLC system. Total polyphenols were analyzed according to the Folin-Ciocalteu method using gallic acid as a standard and the results were presented as gallic acid equivalents. The wines were also analyzed for anthocyanins content using malvidin-3,5-diglucoside as a reference material in spectrophotometric analysis. 相似文献
613.
Grzegorz Zatryb Artur Podhorodecki Jan Misiewicz Julien Cardin Fabrice Gourbilleau 《Nanoscale research letters》2013,8(1):40
Abstract
Silicon nanocrystals embedded in a silicon oxide matrix were deposited by radio frequency reactive magnetron sputtering. By means of Raman spectroscopy, we have found that a compressive stress is exerted on the silicon nanocrystal cores. The stress varies as a function of silicon concentration in the silicon-rich silicon oxide layers varies, which can be attributed to changes of nanocrystal environment. By conducting the Fourier transform infrared absorption experiments, we have correlated the stresses exerted on the nanocrystal core to the degree of matrix structural order.PACS
78.67.Bf, 78.67.Pt, 73.63.Bd, 78.47.D, 74.25.Nd 相似文献614.
615.
Grzegorz Kondrak 《Computers and the Humanities》2003,37(3):273-291
The computation of the optimal phonetic alignment andthe phonetic similarity between wordsis an important step in many applications in computational phonology,including dialectometry.After discussing several related algorithms,I present a novel approach to the problem that employsa scoring scheme for computing phonetic similarity between phonetic segmentson the basis of multivalued articulatory phonetic features.The scheme incorporates the key concept of feature salience,which is necessary to properly balance the importance of various features.The new algorithm combines several techniquesdeveloped for sequence comparison:an extended set of edit operations,local and semiglobal modes of alignment,and the capability of retrieving a set of near-optimal alignments.On a set of 82 cognate pairs,it performs better than comparable algorithms reported in the literature. 相似文献
616.
We consider the problem of waking up n processors in a completely broadcast system. We analyze this problem in both globally and locally synchronous models, with or without n being known to the processors and with or without labeling of the processors. The main question we answer is: how fast we can wake up all the processors with probability 1 - ε in each of these eight models? In [12] a logarithmic waking algorithm for the strongest set of assumptions is described, while for weaker models only linear and quadratic algorithms were obtained. We prove that in the weakest model (local synchronization, no knowledge of n or labeling) the best waking time is O(n/log n). We also show logarithmic or polylogarithmic probabilistic waking algorithms for all stronger models, which in some cases gives an exponential improvement over previous results. 相似文献
617.
Free fatty acids are released over time in vegetable oils, primarily through the hydrolysis of the triglyceride base. In mineral oils, fatty acids are considered to be one of the classical boundary lubrication additives, but they may not have the same impact in vegetable oils, due to the vast difference in chemistry between the base oils. The purpose of this study was to evaluate the influence of free fatty acids on the boundary lubrication performance of sunflower oil, with particular focus on the impact of unsaturation within the fatty acid and assessing the effect of elevated temperatures. The results obtained suggest stearic acid can effectively reduce both the wear and friction of sunflower oil formulations under boundary lubrication conditions, although performance is limited when bulk oil temperatures approach 150°C. 相似文献
618.
W?adyslaw Knabe JarosW?aw Przew?ócki Grzegorz Ró?yński 《Probabilistic Engineering Mechanics》1998,13(3):147-167
The paper deals with the modelling of the soil medium as a random field. The necessity of using local random averages in numerical and analytical stochastic calculations are the main interest. The paper concentrates on linear elements and on the calculation of the variances and covariances of local random variables averaged over these elements. Several equations are derived by analytical integration, both for isotropic and anisotropic random fields. These should be useful for calculation, analysis and a better understanding of the influence of the geometry of elements and the value of parameters of random fields on the covariances of local averages. 相似文献
619.
The aim of this paper is to develop a formal theory of Mizar types. The examples are extracted from Mizar Mathematical Library (MML), some of them are simplified or presented in a bit different way. The presented theory is an approach to the structure of Mizar types as a sup-semilattice with widening (subtyping) relation as the order. It is an abstraction from the existing implementation of the Mizar verifier by Andrzej Trybulec and Czesław Byliński. The theory describes the structure of types of the base fragment of Mizar language. 相似文献
620.
This paper studies the problem of maximizing the number of correct results of dependent tasks computed unreliably. We consider
a distributed system composed of a reliable server that coordinates the computation of a massive number of unreliable workers.
Any worker computes correctly with probability p < 1. Any incorrectly computed task corrupts all dependent tasks. The goal
is to determine which tasks should be computed by the (reliable) server and which by the (unreliable) workers, and when, so
as to maximize the expected number of correct results, under a constraint d on the computation time. This problem is motivated
by distributed computing applications that persist partial results of computations for future use in other computations and
that want to ensure that the persisted results are of high quality. We show that this optimization problem is NP-hard. Then
we study optimal scheduling solutions for the mesh with the tightest deadline. We present combinatorial arguments that describe
all optimal solutions for two ranges of values of worker reliability p, when p is close to zero and when p is close to one. 相似文献