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101.
Kumar R Spuesens T Mechet P Kumar P Raz O Olivier N Fedeli JM Roelkens G Baets R Van Thourhout D Morthier G 《Optics letters》2011,36(13):2450-2452
Using a 7.5 μm diameter disk fabricated with III-V-on-silicon fabrication technology, we demonstrate bias-free all-optical wavelength conversion for non-return-to-zero on-off keyed pseudorandom bit sequence (PRBS) data at the speed of 10 Gbits/s with an extinction ratio of more than 12 dB. The working principle of such a wavelength converter is based on free-carrier-induced refractive index modulation in a pump-probe configuration. We believe it to be the first bias-free on-chip demonstration of all-optical wavelength conversion using PRBS data. All-optical gating measurements in the pump-probe configuration with the same device have revealed that it is possible to achieve wavelength conversion beyond 20 Gbits/s. 相似文献
102.
We introduce a new distance measure between two preorders that captures indifference, strict preference, weak preference and incomparability relations. This measure is the first to capture weak preference relations. We illustrate how this distance measure affords decision makers greater modeling power to capture their preferences, or uncertainty and ambiguity around them, by using our proposed distance measure in a multiple criteria aggregation procedure for mixed evaluations. 相似文献
103.
We show that any element of the universal Teichmüller space is realized by a unique minimal Lagrangian diffeomorphism from
the hyperbolic plane to itself. The proof uses maximal surfaces in the 3-dimensional anti-de Sitter space. We show that, in
AdS
n+1, any subset E of the boundary at infinity which is the boundary at infinity of a space-like hypersurface bounds a maximal space-like hypersurface.
In AdS3, if E is the graph of a quasi-symmetric homeomorphism, then this maximal surface is unique, and it has negative sectional curvature.
As a by-product, we find a simple characterization of quasi-symmetric homeomorphisms of the circle in terms of 3-dimensional
projective geometry. 相似文献
104.
Jean-Marc Bourgeois 《Helvetica chimica acta》1976,59(6):2114-2124
Treatment of 3-C-cyano-1,2:5,6-di-O-isopropylidene-3-O-(toluene-p-sulfonyl)-α-D -allofurannose with AlLiH4 yields a sugar-spiro-aziridine and a branched chain sulfonamide. Reaction mechanisms are briefly discussed and the configurations of the products obtained are proved by chemical reactions. With hydrogenation, the spiro compound is opened to a branched chain amino sugar with the same tertiary carbon as in vancosamine. Several derivatives of this new compound are described: the 6-deoxy sugars in series L and D and the pentose resulting from its oxidation by periodic acid. The conformation around C(4)–C(5) bond is deduced for three compounds from NMR. data. 相似文献
105.
We present low complexity models for the transport of passive scalars for environmental applications. The model uses partial observations assimilation. Similitude solutions are proposed in a non symmetric metric based on travel times. The approach does not require the solution of any PDE and is mesh free. Also, the solution can be computed in one point only without computing the whole solution. To cite this article: B. Mohammadi, J.-M. Brun, C. R. Mecanique 334 (2006). 相似文献
106.
The goal programming (GP) model is probably the best known in mathematical programming with multiple objectives. Available in various versions, GP is one of the most powerful multiple objective methods which has been applied in much varied fields. It has also been the target of many criticisms among which are those related to the difficulty of determining precisely the goal values as well as those concerning the decision-maker's near absence in this modelling process. In this paper, we will use the concept of indifference thresholds for modelling the imprecision related to the goal values. Many classical imprecise and fuzzy GP model formulations can be considered as a particular case of the proposed formulation. 相似文献
107.
Yu Shen Jean-Yves Potvin Jean-Marc Rousseau Serge Roy 《Annals of Operations Research》1995,61(1):189-211
In this paper, we describe an expert consulting system for a dispatcher working in a courier service company. The system integrates interactive-graphic features and a learning module to support the dispatcher in his(her) task, and to suggest appropriate decisions when new requests come in. An experiment with a professional dispatcher is also reported. 相似文献
108.
Jean-Marc Fontaine 《Inventiones Mathematicae》1994,115(1):151-161
Sans résuméOblatum 21-VI-1993 相似文献
109.
110.
The purpose of this paper is to construct a new non-parametric detector of univariate outliers and to study its asymptotic properties. This detector is based on a Hill’s type statistic. It satisfies a unique asymptotic behavior for a large set of probability distributions with positive unbounded support (for instance: for the absolute value of Gaussian, Gamma, Weibull, Student or regular variations distributions). We have illustrated our results by numerical simulations which show the accuracy of this detector with respect to other usual univariate outlier detectors (Tukey, MAD or Local Outlier Factor detectors). The detection of outliers in a database providing the prices of used cars is also proposed as an application to real-life database. 相似文献