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991.
基于面向对象技术的多媒体CAI素材库系统 总被引:1,自引:0,他引:1
建立实用、高效的多媒体CAI素材库是高效率、高质量开发CAI软件的基础和关键.本文从数据模型、面向对象分析和存储模式三方面入手,提出一种支撑CAI制作工具的素材库体系结构,并讨论该体系结构的特性和进一步研究的问题. 相似文献
992.
分析了校园MIS及数据资源的特征,针对校园信息资源范围广、关联复杂的状况,提出了数据资源统一访问策略——分层访问.数据访问分为七层,各层完成数据访问独立性的特定功能,使不同的访问软件能透明访问全部数据资源.为保证传统应用能基于网络计算访问统一数据资源,又提出了“数据访问管道”和数据库访问服务器的技术.文章分析了以应用服务器为基础的N-Tiers计算的弊端,设计了“虚拟应用服务器”WUV-APPS,将数据访问对象构造成数据对象组件. 相似文献
993.
Zhan-Qian Lu 《Journal of multivariate analysis》1999,70(2):177
Theories of nonparametric regression are usually based on the assumption that the design density exists. However, in some applications such as those involving high-dimensional or chaotic time series data, the design measure may be singular and may be likely to have a fractal (nonintegral) dimension. In this paper, the popular Nadaraya–Watson estimator is studied under the general setup that the continuity of the design measure is governed by the local or pointwise dimension. It will be shown in the iid setup that the nonparametric regression estimator achieves a convergence rate which is dependent only on the pointwise dimension. The case of time series data is also studied. For the latter case, a new mixing condition is introduced, and an assumption of marginal or joint density is completely avoided. Three examples, a fractal regression and two applications for predicting chaotic time series, are used to illustrate the implications of the obtained results. 相似文献
994.
随机删失数据下核密度估计的Berry-Esseen界 总被引:2,自引:0,他引:2
本文在随机删失数据下研究了概率密度函数的核估计,获得了此核估计的一个Berry-Esseen界. 相似文献
995.
截尾数据非参数回归函数加权核估计 总被引:4,自引:0,他引:4
在截尾数据下研究非参数回归函数加权核估计的相合性,对强相合性给出一些较弱的充分条件,这些结论较大程度地改进了现有的结论. 相似文献
996.
无失效数据失效率的综合多层Bayes估计 总被引:5,自引:1,他引:4
文章对指数分布无失效数据的失效率,在先验分布为Gamma分布时,在引进失效信息后,给出了多层Bayes估计以及综合多层Bayes估计,并给出了可靠度的综合估计。最后,结合实际问题进行了计算 相似文献
997.
A.A. Yukhimchuk V.A. Apasov Yu.I. Vinogradov A.N. Golubkov E.V. Gornostaev S.K. Grishechkin L.V. Drakin N.A. Zagoruiko V.N. Istratov P.D. Ishkov A.A. Kononenko G.I. Karyakin V.G. Klevtsov V.A. Klisch V.N. Lobanov A.P. Maksimenko S.S. Matveev A.E. Nikitin V.I. Pustovoy I.I. Sukhoi V.M. Solyankin B.N. Tenyaev V.M. Kharitonov 《Hyperfine Interactions》1999,119(1-4):341-344
A facility is described that allows safe handling of high tritium gas activity as dozens kilocuries in a regular laboratory
environment. It is used to make and deliver into the target a mixture of specific isotopic composition with the contamination
requirement of 10-7 v.f. for Z>1 elements, and recover it upon completion of operation. With this facility, efforts have been accomplished to investigate
into the muon catalyzed fusion on two targets – liquid tritium and high-pressure tritium types. Also, the operation range
was 0.1–120 MPa for pressure and 20–800 K for temperature and the amount of tritium used was about 100 kCi. The facility showed
reliability in operation without indications of radiation beyond the safety level.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
998.
We present new theoretical calculations of nuclear fusion rates λ
f
J
from the resonant states of the muonic molecular ion 3Hedμ
++ with total angular momenta J=0,1. As a byproduct, new very accurate variational wave functions for these states have been obtained. Using these wave functions,
the probability density |Ψ(R=0)|2 in a fusion region has been calculated by extrapolating the variational solution to small internuclear distances by means
of the multi-channel adiabatic solution. Calculated fusion rates for the states J=0 and J=1 are: λ
f
0
=1.9·105s-1 and λ
f
1
=0.65·103s-1, respectively.
This revised version was published online in August 2006 with corrections to the Cover Date. 相似文献
999.
1000.
KM Varier AM Vinodkumar NVSV Prasad PV Madhusudhana Rao DL Sastry Lagy T Baby MC Radhakrishna NG Puttaswamy JJ Das P Sugathan N Madhavan AK Sinha DO Kataria 《Pramana》1999,53(3):529-533
Large enhancements have been observed in the sub-barrier fusion cross sections for Ti+Ni systems in our previous studies.
Coupled channel calculations incorporating couplings to 2+ and 3− states failed to explain these enhancements completely. A possibilty of transfer channels contributing to the residual enhancements
had been suggested. In order to investigate the role of relevant transfer channels, measurements of one- and two-nucleon transfer
were carried out for 46,48Ti+61Ni systems. The present paper gives the results of these studies. 相似文献