功率器件有 JTE 结构的电场的数值分析与模拟

本文用 damped-Newton(DN)法求解由一般非线性方程获得的Poisson 方程。研究了阻尼因子λ对其收敛性和求解效率的影响。利用此方法计算了横向表面掺杂为 Gauss 分布的器件的归一化电场与掺杂浓度和掺杂层宽度的关系。     

数字式同步发电机微机励磁调节装置

介绍了同步发电机数字微机励磁装置。该装置综合运用了同步发电机的暂态运行理论、稳态运行理论以及自动控制理论,采用了目前国际上较流行的数字控制技术及电力电子技术。其主控单元通过对同步发电机的运行参数、运行曲线及特性曲线进行优化处理,达到对同步电机运行的自动控制。     

长齿条的加工工艺分析

长齿条由于尺寸太长而无法在通用设备上加工,改装有车齿装置的C630-Ⅱ型车床可同时加工几十根齿条;X63型铣床采用专用铣头后也可加工,两者有不同的优缺点,决定了不同的使用场合.     

On Bayesian consistency

We consider a sequence of posterior distributions based on a data-dependent prior (which we shall refer to as a pseudoposterior distribution) and establish simple conditions under which the sequence is Hellinger consistent. It is shown how investigations into these pseudo posteriors assist with the understanding of some true posterior distributions, including Pólya trees, the infinite dimensional exponential family and mixture models.     

论器具信息技术

器具信息技术是信息技术中不同于身体信息技术的另一个重要种类,信息的载入设备、载体和媒介是考察器具信息技术的三个重要侧面,它们集合形成了不同时代的信息装置范式,信息装置范式的演变标志着人类文明形态的演变。器具信息技术具有作为人造物、折射人的本质以及指向信息等三个总体特征。     

1300V/20A绝缘栅双极晶体管IGBT

基于理论概括与实验研究,已经在N~-/N~+/P~+外延基片上获得了1300V/20A高性能IGBT;并进而指出了实现该器件互相关联的关键技术。它们分别是:优质厚层低缺陷密度异型硅外延材料的工艺制备,器件纵横向几何结构及工作参数的准确量化,和通过叠加组合形成的复合高压终端结构。     

利用情绪生成心理机制培养学生的自我效能感

本文从情绪生成心理机制的角度论述了学生自我效能感的培养 ,着重强调了如何利用需要、客体与预期的关系、观察性学习、表情训练、认知和评价、兴趣等因素来培养学生的自我效能感 ,并指出自我效能感培养的最终目标是使学生能将之内化为自身性格并能有意识地在该方面进行自我教育。     

绕射辐射振荡器研究

介绍了“绕射辐射振荡器研究”的成果，简述了理论分析、三维计算及设计方法；给出了实验结果并对有关问题进行了讨论。实验管测试的主要参量为：在工作电压２４００～４０００Ｖ；频率范围ｆ＝８４～１０４ＧＨｚ内测得高频振荡，最大输出功率达２００ｍｗ。频率范围ｆ＝６０～８２ＧＨｚ；最大输出功率达１．３Ｗ。同时介绍了这种器件在科学技术中的应用。     

Sieve Empirical Likelihood and Extensions of the Generalized Least Squares

The empirical likelihood cannot be used directly sometimes when an infinite dimensional parameter of interest is involved. To overcome this difficulty, the sieve empirical likelihoods are introduced in this paper. Based on the sieve empirical likelihoods, a unified procedure is developed for estimation of constrained parametric or non-parametric regression models with unspecified error distributions. It shows some interesting connections with certain extensions of the generalized least squares approach. A general asymptotic theory is provided. In the parametric regression setting it is shown that under certain regularity conditions the proposed estimators are asymptotically efficient even if the restriction functions are discontinuous. In the non-parametric regression setting the convergence rate of the maximum estimator based on the sieve empirical likelihood is given. In both settings, it is shown that the estimator is adaptive for the inhomogeneity of conditional error distributions with respect to predictor, especially for heteroscedasticity.     

Estimation of General Stationary Processes by Variable Length Markov Chains

We develop new results about a sieve methodology for the estimation of minimal state spaces and probability laws in the class of stationary processes defined on finite categorical spaces. Using a sieve approximation with variable length Markov chains of increasing order, we show that an adapted version of the Context algorithm yields asymptotically correct estimates for the minimal state space and for the underlying probability distribution. As a side product, the method of sieves yields a nice graphical tree representation for the potentially infinite dimensional minimal state space of the data generating process, which is very useful for exploration of the memory.