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81.
Thomas J. Cloonan Gaylord W. Richards Anthony L. Lentine Frederick B. McCormick John R. Erickson 《Optical and Quantum Electronics》1992,24(4):S415-S442
Free-space optical implementations of switching networks have been proposed to circumvent many of the system-level problems that may be encountered in systems that require many high-density, high-bandwidth connections. The details of a new class of switching network (the EGS network), that is well-suited to free-space implementations, is described. The common control injection problem that plagues most free-space photonic networks, i.e. how can control information from an electronic source be injected into the network for applications that require relatively high network reconfiguration rates, is examined. A new technique for control injection, called embedded control, which permits network operation even with relatively high network reconfiguration rates is also proposed. 相似文献
82.
83.
84.
The existing model for multivariate skew normal data does not cohere with the joint distribution of a random sample from a
univariate skew normal distribution. This incoherence causes awkward interpretation for data analysis in practice, especially
in the development of the sampling distribution theory. In this paper, we propose a refined model that is coherent with the
joint distribution of the univariate skew normal random sample, for multivariate skew normal data. The proposed model extends
and strengthens the multivariate skew model described in Azzalini (1985,Scandinavian Journal of Statistics,12, 171–178). We present a stochastic representation for the newly proposed model, and discuss a bivariate setting, which confirms
that the newly proposed model is more plausible than the one given by Azzalini and Dalla Valle (1996,Biometrika,83, 715–726). 相似文献
85.
John B. Little 《Geometriae Dedicata》2004,104(1):233-234
We correct an error in Example (3.4) in Geom. Dedicata
31 (1989), 19–35. 相似文献
86.
87.
Andrew C. Brooks Peter Day John D. Wallis 《Acta Crystallographica. Section C, Structural Chemistry》2008,64(5):o245-o247
The crystal structure of the title compound [systematic name: 2‐(1,3‐dithiolo[4,5‐b][1,4]dithiin‐2‐ylidene)‐6,6‐bis(methoxyethoxymethoxymethyl)‐1,3‐dithiolo[4,5‐b][1,4]dithiepine], C21H30O6S8, a spiro‐substituted BEDT–TTF analogue [BEDT–TTF is bis(ethylenedithio)tetrathiafulvalene], has a strongly bent heterocyclic framework. The seven‐membered ring adopts a pseudo‐chair conformation with notably widened ring bond angles, especially at the methylene C atoms [119.49 (11) and 117.60 (11)°]. The axial side chain adopts an extended conformation, but the equatorial side chain curls back on itself and the O atom nearest the ring system is involved in three short contacts to H atoms (2.45–2.53 Å). The molecules pack in centrosymmetrically related pairs, which are isolated from each other by columns of the polyether side chains. This study emphasizes the ease of distortion of the neutral bis(propylenedithio)tetrathiafulvalene ring structure, and how the need to accommodate side chains can easily override the tendency of these donor systems to form stacks in the crystalline state. 相似文献
88.
A convenient methodology for introducing single functional groups to the lower rim of resorcinarenes is described. The methodology allows for very convenient differential protection or derivatisation of the upper and lower rims, and a wide range of functional groups (alcohol, carboxylic acid, thiol, amine, carbamate, alkyl halide) can be incorporated as a single unit at the lower rim, opening up the way to further modification at this point and generally widening the scope for further utilising resorcinarenes. Furthermore, our approach has enabled us to link two resorcinarenes together to form novel resorcinarene dimers. 相似文献
89.
Bourget Alain Jakobson Dmitry Min-Oo Maung Toth John A. 《Letters in Mathematical Physics》2003,64(2):105-118
We determine the limiting density of the zeroes of Heine–Stieltjes polynomials (or of any set of points satisfying the conclusion of Heine–Stieltjes Theorem) in the thermodynamic limit and use this to prove a strong law of large numbers for the zeroes. 相似文献
90.
Detailed chemical kinetic mechanisms of complex chemical phenomena may be composed of hundreds of species and thousands of individual elementary reactions. It can be an extremely laborious and error‐prone procedure to compare two of these mechanisms, particularly if they come from different sources. We have created software tools which help to highlight the differences between mechanisms written in a Chemkin format and demonstrate their applicability to five literature mechanisms describing the high temperature oxidation of methane. © 2004 Wiley Periodicals, Inc. Int J Chem Kinet 36:467–471, 2004 相似文献