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11.
针对世博会巨额亏损这一重大课题,笔者分析并找出了汉诺威2000年世博会亏损的影响因素,并将这些因素运用于上海世博会的经济风险分析,根据汉诺威世博有限公司的经验,指出上海世博公司需要引起注意的几个方面,结合我国和上海的实际情况,为上海世博公司提出预防、规避和分散经济风险的方案和建议.  相似文献   
12.
阐述了IPv6的基本原理 ,详细说明了在WIN2 0 0 0操作系统环境下 ,如何进行IPv6网络实现的实验研究。  相似文献   
13.
For randomly censored data, the authors propose a general class of semiparametric median residual life models. They incorporate covariates in a generalized linear form while leaving the baseline median residual life function completely unspecified. Despite the non‐identifiability of the survival function for a given median residual life function, a simple and natural procedure is proposed to estimate the regression parameters and the baseline median residual life function. The authors derive the asymptotic properties for the estimators, and demonstrate the numerical performance of the proposed method through simulation studies. The median residual life model can be easily generalized to model other quantiles, and the estimation method can also be applied to the mean residual life model. The Canadian Journal of Statistics 38: 665–679; 2010 © 2010 Statistical Society of Canada  相似文献   
14.
This paper is concerned with undoing aliasing effects, which arise from discretely sampling a continuous‐time stochastic process. Such effects are manifested in the frequency‐domain relationships between the sampled and original processes. The authors describe a general technique to undo aliasing effects, given two processes, one being a time‐delayed version of the other. The technique is based on the observations that certain phase information between the two processes is unaffected by sampling, is completely determined by the (known) time delay, and contains sufficient information to undo aliasing effects. The authors illustrate their technique with a simulation example. The theoretical model is motivated by the helioseismological problem of determining modes of solar pressure waves. The authors apply their technique to solar radio data, and conclude that certain low‐frequency modes known in the helioseismology literature are likely the result of aliasing effects. The Canadian Journal of Statistics 38: 116–135; 2010 © 2010 Statistical Society of Canada  相似文献   
15.
The evaluation of new processor designs is an important issue in electrical and computer engineering. Architects use simulations to evaluate designs and to understand trade‐offs and interactions among design parameters. However, due to the lengthy simulation time and limited resources, it is often practically impossible to simulate a full factorial design space. Effective sampling methods and predictive models are required. In this paper, the authors propose an automated performance predictive approach which employs an adaptive sampling scheme that interactively works with the predictive model to select samples for simulation. These samples are then used to build Bayesian additive regression trees, which in turn are used to predict the whole design space. Both real data analysis and simulation studies show that the method is effective in that, though sampling at very few design points, it generates highly accurate predictions on the unsampled points. Furthermore, the proposed model provides quantitative interpretation tools with which investigators can efficiently tune design parameters in order to improve processor performance. The Canadian Journal of Statistics 38: 136–152; 2010 © 2010 Statistical Society of Canada  相似文献   
16.
For many diseases, logistic constraints render large incidence studies difficult to carry out. This becomes a drawback, particularly when a new study is needed each time the incidence rate is investigated in a new population. By carrying out a prevalent cohort study with follow‐up it is possible to estimate the incidence rate if it is constant. The authors derive the maximum likelihood estimator (MLE) of the overall incidence rate, λ, as well as age‐specific incidence rates, by exploiting the epidemiologic relationship, (prevalence odds) = (incidence rate) × (mean duration) (P/[1 ? P] = λ × µ). The authors establish the asymptotic distributions of the MLEs and provide approximate confidence intervals for the parameters. Moreover, the MLE of λ is asymptotically most efficient and is the natural estimator obtained by substituting the marginal maximum likelihood estimators for P and µ into P/[1 ? P] = λ × µ. Following‐up the subjects allows the authors to develop these widely applicable procedures. The authors apply their methods to data collected as part of the Canadian Study of Health and Ageing to estimate the incidence rate of dementia amongst elderly Canadians. The Canadian Journal of Statistics © 2009 Statistical Society of Canada  相似文献   
17.
The author considers estimation under a Gamma process model for degradation data. The setting for degradation data is one in which n independent units, each with a Gamma process with a common shape function and scale parameter, are observed at several possibly different times. Covariates can be incorporated into the model by taking the scale parameter as a function of the covariates. The author proposes using the maximum pseudo‐likelihood method to estimate the unknown parameters. The method requires usage of the Pool Adjacent Violators Algorithm. Asymptotic properties, including consistency, convergence rate and asymptotic distribution, are established. Simulation studies are conducted to validate the method and its application is illustrated by using bridge beams data and carbon‐film resistors data. The Canadian Journal of Statistics 37: 102‐118; 2009 © 2009 Statistical Society of Canada  相似文献   
18.
通过对视频服务器相关资料的研究,提出了一种基于ADI公司专用DSP芯片ADSP-BF561的无线视频服务器的解决方案。硬件设计采用SAA7113芯片完成输入视频A/D转换,以ADSP-BF561芯片为核心硬件平台实现视频压缩编码,利用相应外围设备实现网络控制和传输。该方案由于使用了H.264视频编码标准、G729音频编码标准和基于CDMA1X无线网络技术的CDMA无线网络作为音视频数据的传输途径,具有良好的稳定性和可实现性。  相似文献   
19.
描述了基于ITU-R M.1225的包括室内、室外到室内/步行和车载等测试环境的IMT-2000信道模拟器设计及仿真实现。重点分析了实现该信道模拟器慢衰落的相关性整形和频率选择性多径衰落的实时硬件实现两个算法,给出了数值计算和仿真结果,结果表明该信道模拟器较好地仿真出了2 GHz信道的一阶和二阶统计特性,可作为第三代移动通信研究和设备研制的有效工具。  相似文献   
20.
文章介绍了Word 2000绘图工具的使用方法,结合绘制力学课程课件的插图,总结了力学课程插 图的种种绘制方法和经验,对绘制课程插图的初学者有一定的指导意义,对经常使用Word 2000且有一定 经验者也具有参考价值。  相似文献   
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