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31.
32.
HOU Xiao-lin LI Shu-bo YIN Chang-chuan YUE Guang-xin School of Telecommunication Engineering Beijing University of Posts Telecommunications Beijing P.R. China 《中国邮电高校学报(英文版)》2004,11(3)
1 Introduction Linkadaptationtechniqueisnowwidelyrecognizedasakeysolutiontoincreasethespectralefficiencyofwire lesssystems[1~ 3] .GPRS ,EDGE ,cdma2 0 0 0andWCDMAallincludelinkadaptationasameanstopro videhigherdatarates[4~ 5] .Torealizethepotentialoflinkadaptation ,reliablechannel predictionisneces sary[6 ] . Therearemanydifferentchannelpredictionmethodsavailablenow ,suchasLongRangePrediction(LRP) [6 ] ,predictionbasedonsubspacesignalprocess ingalgorithms[7] ,predictionbasedonFinit… 相似文献
33.
We look at the task of computing the time-evolution of a non-linear system for a long time, in our case under random external
influences. Our specific example is the fatigue evaluation of a wind turbine. To facilitate such a computation, we look at
a reduction of the computational effort by projecting everything on a low-dimensional basis. In this case we take the Karhunen-Loève
basis generated from running the model a little while under the random loading. It is important that the error which is caused
by this reduction process can be controlled. We estimate the error by dual or adjoint methods. This in turn allows the process
of model reduction to be performed adaptively.
Dedicated to the memory of Prof. Mike Crisfield, for his cheerfulness and cooperation as a colleague and friend over many
years. 相似文献
34.
1 IntroductionWiththerapiddevelopmentofInternetandmobilecommunications,theresearchonwirelessmobilenetworkshasbecomethenewhotspotinin formationtechnologyfield .Asweknow ,mobileterminals (mobilephone,forexample)arethetooltohelppeopletoaccessanyinformationtheyneedbyanymediaatanytimeandanywhere .However,itissometimesdifficultformobileterminalstoplaysucharolebecauseofthelimitationssuchaslimitedca pacity ,lowpower,andinconvenienceinoperating .So,peoplehopetofindanotherwaytoaccessnet workinformatio… 相似文献
35.
Marcio Schwaab 《Chemical engineering science》2006,61(17):5791-5806
Model discrimination procedures are useful tools for selection of the best mathematical models to be used to represent a specific chemical process. The present paper presents and discusses a new sequential discrimination procedure, which makes use of model probabilities and concentrates the efforts on models with higher probabilities. Model probabilities are determined based on simple statistical arguments. Four numerical examples illustrate the application of the proposed discrimination procedure. The obtained results indicate that the new procedure is able to discriminate kinetic models with fewer experiments when compared to other procedures and also indicates when model discrimination is not possible and, thus, when the sequential design must be halted. Furthermore, the speed of the proposed discrimination procedure can be controlled by tuning a design parameter which reflects the analyst's mood (confidence) towards the discrimination problem and allows for increase or decrease of the number of experiments required for model discrimination during the sequential procedure. 相似文献
36.
精镗孔尺寸误差预测补偿技术的研究概况与趋势 总被引:2,自引:0,他引:2
提出了精镗孔尺寸误差预测补偿技术存在的主要问题,指出了今后所需研究的主要内容及关键技术。 相似文献
37.
图像压缩编码方法分析 总被引:1,自引:0,他引:1
介绍图像压缩编码技术发展过程,对图像压缩编码,特别是自适应预测编码、模型法编码、分形编码、小波变换压缩编码、神经网络压缩编码原理和特点进行分析,并阐述图像压缩编码的作用. 相似文献
38.
M. Sreekanth D. Ruben Sudhakar B.V.S.S.S. Prasad Ajit Kumar Kolar B. Leckner 《Fuel》2008,87(12):2698-2712
A two-dimensional model is developed for the determination of devolatilization time and char yield of cylindrical wood particles in a bubbling fluidized bed combustor. By using the concept of shape factor, the model is extended to particles of cuboid shape. The model prediction of the devolatilization time agrees with the measured data (present and those reported in the literature) for cylindrical and cuboidal shaped particles within ±20% while the char yield is predicted within ±17%. Influence of some important parameters namely, thermal diffusivity, external heat transfer coefficient and shrinkage, on the devolatilization time and char yield are studied. Thermal diffusivity shows noticeable influence on devolatilization time. The external heat transfer coefficient shows little influence beyond a value of 300 W/(m2 K). However particle shrinkage shows negligible effect on the devolatilization time but has a significant influence on the char yield. 相似文献
39.
40.
Statistical machine translation systems are usually trained on large amounts of bilingual text (used to learn a translation
model), and also large amounts of monolingual text in the target language (used to train a language model). In this article
we explore the use of semi-supervised model adaptation methods for the effective use of monolingual data from the source language
in order to improve translation quality. We propose several algorithms with this aim, and present the strengths and weaknesses
of each one. We present detailed experimental evaluations on the French–English EuroParl data set and on data from the NIST
Chinese–English large-data track. We show a significant improvement in translation quality on both tasks. 相似文献