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1.
We propose a standardization procedure that provides a convenient, quantitative and reproducible laboratory-based method for measuring the state of polarization (SOP) fluctuations produced by polarization varying devices. This method is based on the SOP distributions generated by commercial polarization scramblers. We show that these devices generate distributions of the maximum change of the SOP (in a given sample time) that follow Rayleigh statistics, which scale linearly with scrambling frequency and the sample time. We use this procedure to measure the SOP fluctuations in a short length of coiled fiber subject to mechanical perturbations. 相似文献
2.
3.
Jen-Chwen Lin T. Leo Ngai Y. Austin Chang 《Metallurgical and Materials Transactions A》1986,17(7):1241-1245
Defect equilibria for binary semiconducting compound phases which exhibit ionized native donor and acceptor defects were considered,
and equations describing the pressure-temperature-composition relationships for these compound phases were derived. These
equations were used to analyze experimental data from the literature for tin telluride. Excellent agreement was obtained between
calculated thermodynamic and phase boundary values and experimental data. The approach presented is readily extended to obtain
equations for the thermodynamic properties of ternary and higher order semiconducting compound phases. 相似文献
4.
We show that the composition of two information production processes (IPPs), where the items of the first IPP are the sources
of the second, and where the ranks of the sources in the first IPP agree with the ranks of the sources in the second IPP,
yields an IPP which is positively reinforced with respect to the first IPP. This means that the rank-frequency distribution
of the composition is the composition of the rank-frequency distribution of the first IPP and an increasing function φ, which is explicitly calculable from the two IPPs' distributions. From the rank-frequency distribution of the composition,
we derive its size-frequency distribution in terms of the size-frequency distribution of the first IPP and of the function
φ. The paper also relates the concentration of the reinforced IPP to that of the original one. This theory solves part of the
problem of the determination of a third IPP from two given ones (so-called three-dimensional informetrics). In this paper
we solved the “linear” case, i.e., where the third IPP is the composition of the other two IPPs.
This revised version was published online in June 2006 with corrections to the Cover Date. 相似文献
5.
Leo Egghe 《Scientometrics》2005,63(2):277-296
Summary We study new and existing data sets which show that growth rates of sources usually are different from growth rates of items. Examples: references in publications grow with a rate that is different (usually higher) from the growth rate of the publications themselves; article growth rates are different from journal growth rates and so on. In this paper we interpret this phenomenon of “disproportionate growth' in terms of Naranan's growth model and in terms of the self-similar fractal dimension of such an information system, which follows from Naranan's growth model. The main part of the paper is devoted to explain disproportionate growth. We show that the “simple' 2-dimensional informetrics models of source-item relations are not able to explain this but we also show that linear 3-dimensional informetrics (i.e. adding a new source set) is capable to model disproportionate growth. Formulae of such different growth rates are presented using Lotkaian informetrics and new and existing data sets are presented and interpreted in terms of the used linear 3-dimensional model. 相似文献
6.
This paper addresses one of the central problems arising at the transfer stage in machine translation: syntactic mismatches,
that is, mismatches between a source-language sentence structure and its equivalent target-language sentence structure. The
level at which we assume the transfer to be carried out is the Deep-Syntactic Structure (DSyntS) as proposed in the Meaning-Text Theory (MTT). DSyntS is abstract enough to avoid all types of divergences that result
either from restricted lexical co-occurrence or from surface-syntactic discrepancies between languages. As for the remaining
types of syntactic divergences, all of them occur not only interlinguistically, but also intralinguistically; this means that
establishing correspondences between semantically equivalent expressions of the source and target languages that diverge with
respect to their syntactic structure is nothing else than paraphrasing. This allows us to adapt the powerful intralinguistic
paraphrasing mechanism developed in MTT for purposes of interlinguistic transfer. 相似文献
7.
Equal Strain Consolidation by Vertical Drains 总被引:1,自引:0,他引:1
Chin Jian Leo 《Canadian Metallurgical Quarterly》2004,130(3):316-327
This paper shows the development of a series of closed-form solutions of equal strain consolidation in the presence of a vertical drain with smear and well resistance. Using an approach that considers the effects of both the radial and vertical drainage in a fully coupled fashion, solutions are obtained for the excess pore pressure and the degree of consolidation in the compressible soil subjected to a step- or ramp-loading situation. The closed-form solutions in the present paper may be evaluated in an electronic spreadsheet on a standard personal computer. 相似文献
8.
KU Leo JM Grace Q Li J Peggins AL Mitchell T Aguilar TG Brewer 《Canadian Metallurgical Quarterly》1997,54(5):276-284
Arteether (AE) is primarily deethylated to dihydroqinghaosu (DQHS) in rats and humans. Conversion of AE to DQHS was impaired in microsomes from rats infected with Plasmodium berghei. The Km for AE was 175.1 +/- 49.1 and 124.4 +/- 115.1 mumol/l, and Vmax was 2.24 +/- 0.45 and 1.22 +/- 0.67 nmol AE formed/mg protein/min in control and infected microsomes (p < 0.05), respectively. Calculated intrinsic clearance (CLint = initial Vmax/Km) for AE was only 4% lower in infected microsomes. Apparent pharmacokinetic parameter estimates for AE using the isolated perfused rat liver demonstrated no differences (p > 0.05) in volume of distribution, clearance, and half-life between normal and infected animals. Malaria infection resulted in decreased biliary excretion of free AE and DQHS. The majority of AE is eliminated via biliary excretion of conjugated DQHS, which is approximately 500-fold higher than free DQHS and 75-fold higher than free AE on a molar basis. 相似文献
9.
10.
Kevin R. Boyle Martijn Udink Anton de Graauw Leo P. Ligthart 《Antennas and Propagation, IEEE Transactions on》2007,55(2):373-382
A dual-fed, self-diplexing planar inverted F antenna and an associated RF front-end are described. It is shown that co-design of the antenna and front-end can be used to double the operational bandwidth, without significant size or performance penalties. Indeed, the use of two feeds allows the antenna to be self-diplexing, which results in improved overall efficiency 相似文献