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排序方式: 共有470条查询结果,搜索用时 15 毫秒
1.
2.
Anatoly M. Dolgonosov Ruslan Kh. Khamizov Anna N. Krachak Andrei G. Prudkovsky 《Reactive and Functional Polymers》1995,28(1)
A model for multispecies ion-exchange kinetics based on the Nernst-Planck equation is suggested. It is analyzed in comparison with the “locally-determinate” model described by Hwang and Helfferich [1]. The model makes possible simple computation. The conditions for the occurrence of unusual kinetic curves with a maximum are clarified. The proposed model is developed for different types of kinetic problems and verified by the experimental investigation of a kinetics in ternary systems. 相似文献
3.
HaengSeok Yang SangKyeong Yun JongHyeong Song SeungDo An HeungWoo Park Shyshkin Ihar Victor Yurlov Lapchuk Anatoly 《Journal of the Society for Information Display》2010,18(6):445-453
Abstract— The development of a compact, efficient VGA projection module to be embedded in mobile devices is reported. The design incorporates laser/laser diode (LD) light sources, Schlieren optics, and a one‐dimensional diffractive spatial optical modulator (SOM). During development, the optical parameters were determined and the relationships between the parameters to optimize the optical specifications were derived. The resulting optimized specifications enable us to manufacture two types of optical modu les as compact as 13 cc and with as little as 10% speckle contrast ratio. 相似文献
4.
Sergio M. Davis Anatoly B. Belonoshko Börje Johansson 《Computer Physics Communications》2011,(5):1105-1110
We present an implementation of a stochastic optimization algorithm applied to location of atomic vacancies. Our method labels an empty point in space as a vacancy site, if the total spatial overlap of a “virtual sphere”, centered around the point, with the surrounding atoms (and other vacancies) falls below a tolerance parameter. A Metropolis-like algorithm displaces the vacancies randomly, using an “overlap temperature” parameter to allow for acceptance of moves into regions with higher overlap, thus avoiding local minima. Once the algorithm has targeted a point with low overlap, the overlap temperature is decreased, and the method works as a steepest descent optimization.Our method, with only two free parameters, is able to detect the correct number and coordinates of vacancies in a wide spectrum of condensed-matter systems, from crystals to amorphous solids, in fact in any given set of atomic coordinates, without any need of comparison with a reference initial structure. 相似文献
5.
Large-scale mapping of boreal forest in SIBERIA using ERS tandem coherence and JERS backscatter data 总被引:3,自引:0,他引:3
Wolfgang Wagner Adrian LuckmanJan Vietmeier Kevin Tansey Heiko BalzterChristiane Schmullius Malcolm Davidson David Gaveau Michael Gluck Thuy Le ToanShaun Quegan Anatoly ShvidenkoAndreas Wiesmann Jiong Jiong Yu 《Remote sensing of environment》2003,85(2):125-144
Siberia's boreal forests represent an economically and ecologically precious resource, a significant part of which is not monitored on a regular basis. Synthetic aperture radars (SARs), with their sensitivity to forest biomass, offer mapping capabilities that could provide valuable up-to-date information, for example about fire damage or logging activity. The European Commission SIBERIA project had the aim of mapping an area of approximately 1 million km2 in Siberia using SAR data from two satellite sources: the tandem mission of the European Remote Sensing Satellites ERS-1/2 and the Japanese Earth Resource Satellite JERS-1. Mosaics of ERS tandem interferometric coherence and JERS backscattering coefficient show the wealth of information contained in these data but they also show large differences in radar response between neighbouring images. To create one homogeneous forest map, adaptive methods which are able to account for brightness changes due to environmental effects were required. In this paper an adaptive empirical model to determine growing stock volume classes using the ERS tandem coherence and the JERS backscatter data is described. For growing stock volume classes up to 80 m3/ha, accuracies of over 80% are achieved for over a hundred ERS frames at a spatial resolution of 50 m. 相似文献
6.
Kemme B. Pedone F. Alonso G. Schiper A. Wiesmann M. 《Knowledge and Data Engineering, IEEE Transactions on》2003,15(4):1018-1032
Atomic broadcast primitives are often proposed as a mechanism to allow fault-tolerant cooperation between sites in a distributed system. Unfortunately, the delay incurred before a message can be delivered makes it difficult to implement high performance, scalable applications on top of atomic broadcast primitives. Recently, a new approach has been proposed for atomic broadcast which, based on optimistic assumptions about the communication system, reduces the average delay for message delivery to the application. We develop this idea further and show how applications can take even more advantage of the optimistic assumption by overlapping the coordination phase of the atomic broadcast algorithm with the processing of delivered messages. In particular, we present a replicated database architecture that employs the new atomic broadcast primitive in such a way that communication and transaction processing are fully overlapped, providing high performance without relaxing transaction correctness. 相似文献
7.
Hideo Araseki Igor R. Kirillov Gennady V. Preslitsky Anatoly P. Ogorodnikov 《Nuclear Engineering and Design》2000,195(1)
This paper describes an experimental and analytical study of double-supply-frequency pressure pulsation arising in an annular linear induction pump. In a large-scale induction pump, it is known that the supply frequency should be relatively low in order to satisfy a magnetohydrodynamic stability criterion. Under such a low supply frequency, however, double-supply-frequency pressure and flow rate pulsation generated in an induction pump may be of concern. The experimental data obtained in the present work shows that the amplitude of the pressure pulsation increases with decreasing supply frequency, number of poles and/or slip. The numerical result reveals that the pressure pulsation comes from a disturbance of the electromagnetic force near the stator ends. 相似文献
8.
9.
Giorgio Dall'Olmo Anatoly A. Gitelson Donald C. Rundquist Bryan Leavitt John C. Holz 《Remote sensing of environment》2005,96(2):176-187
Bio-optical algorithms for remote estimation of chlorophyll-a concentration (Chl) in case-1 waters exploit the upwelling radiation in the blue and green spectral regions. In turbid productive waters other constituents, that vary independently of Chl, absorb and scatter light in these spectral regions. As a consequence, the accurate estimation of Chl in turbid productive waters has so far not been feasible from satellite sensors. The main purpose of this study was to evaluate the extent to which near-infrared (NIR) to red reflectance ratios could be applied to the Sea Wide Field-of-View Sensor (SeaWiFS) and the Moderate Imaging Spectrometer (MODIS) to estimate Chl in productive turbid waters. To achieve this objective, remote-sensing reflectance spectra and relevant water constituents were collected in 251 stations over lakes and reservoirs with a wide variability in optical parameters (i.e. 4 ≤ Chl ≤ 240 mg m− 3; 18 ≤ Secchi disk depth ≤ 308 cm). SeaWiFS and MODIS NIR and red reflectances were simulated by using the in-situ hyperspectral data. The proposed algorithms predicted Chl with a relative random uncertainty of approximately 28% (average bias between − 1% and − 4%). The effects of reflectance uncertainties on the predicted Chl were also analyzed. It was found that, for realistic ranges of Rrs uncertainties, Chl could be estimated with a precision better than 40% and an accuracy better than ± 35%. These findings imply that, provided that an atmospheric correction scheme specific for the red-NIR spectral region is available, the extensive database of SeaWiFS and MODIS images could be used to quantitatively monitor Chl in turbid productive waters. 相似文献