自旋电子在钙钛矿锰氧化物中输运性质研究

本文对国内外研究钙钛矿锰氧化物磁电性质及CMR效应的现状进行了分析,指出有必要研究自旋电子在钙铁矿锰氧化物中的输运性质与材料的磁性以及外加磁场的关系,并对研究方法进行了探讨。     

On Bayesian estimators in multistage binomial designs

A new class of Bayesian estimators for a proportion in multistage binomial designs is considered. Priors belong to the beta-J distribution family, which is derived from the Fisher information associated with the design. The transposition of the beta parameters of the Haldane and the uniform priors in fixed binomial experiments into the beta-J distribution yields bias-corrected versions of these priors in multistage designs. We show that the estimator of the posterior mean based on the corrected Haldane prior and the estimator of the posterior mode based on the corrected uniform prior have good frequentist properties. An easy-to-use approximation of the estimator of the posterior mode is provided. The new Bayesian estimators are compared to Whitehead's and the uniformly minimum variance estimators through several multistage designs. Last, the bias of the estimator of the posterior mode is derived for a particular case.     

Serial dependence and regression of Poisson INARMA models

Time series of counts occur in many fields of practice, with the Poisson distribution as a popular choice for the marginal process distribution. A great variety of serial dependence structures of stationary count processes can be modelled by the INARMA family. In this article, we propose a new approach to the INMA(q) family in general, including previously known results as special cases. In the particular case of Poisson marginals, we will derive new results concerning regression properties and the serial dependence structure of INAR(1) and INMA(q) models. Finally, we present explicit expressions for the distribution of jumps in such processes.     

蜘蛛丝的结构与力学性能

本文主要介绍了蜘蛛丝的形成和力学性能特征，分析了其结构与力学性能间的关系。     

圆锥曲线的光(声)学性质

本文以微分方程为主要工具揭示了圆锥曲线的光(声)学性质。     

对《文物保护法》有关民间收藏文物诸条款的若干思考

2002年10月28日颁布实施的《文物保护法》将原法“私人收藏文物”更名为“民间收藏文物”，并由原来的3条增加到10条。新《文物保护法》对民间收藏文物诸条款的规定，一方面能够适应社会主义市场经济体制建立后所面临的新情况，另一方面在管理制度和政策上有利于实行适度开放的政策，从而达到规范市场，使民间收藏文物有序流通的目的。     

论焓的物理意义

尽管焓在自然科学、工程热物理和热能工程中是使用十分广泛的物理参量,但其物理意义却是不够清楚的。本文首先评价了已有的一些关于焓的物理意义的论点,然后论述并发挥了作者以前论述过的焓中的pv是在压力场为定常时,流体微团在其迹线上的压力势能的观点。为此,需涉及到体系的势能与外力场对体系作功的关系,以及流体微元体在流场中运动时,流场对此微元体的作功关系的定量概念。通过以上论述,以期对探讨焓的物理意义有所帮助。     

Bivariate log Birnbaum–Saunders distribution

Univariate Birnbaum–Saunders distribution has received a considerable amount of attention in recent years. Rieck and Nedelman (A log-linear model for the Birnbaum–Saunders distribution. Technometrics, 1991;33:51–60) introduced a log Birnbaum–Saunders distribution. The main aim of this paper is to introduce bivariate log Birnbaum–Saunders distribution. The proposed model is symmetric and it has five parameters. It can be obtained using Gaussian copula. Different properties can be obtained using copula structure. It is observed that the maximum likelihood estimators (MLEs) cannot be obtained explicitly. Two-dimensional profile likelihood approach may be adopted to compute the MLEs. We propose some alternative estimators also, which can be obtained quite conveniently. The analysis of one data set is performed for illustrative purposes. Finally, it is observed that this model can be used as a bivariate log-linear model, and its multivariate generalization is also quite straight forward.     

磁流变阻尼器结构设计及其阻尼特性试验研究

目前市场上的磁流变阻尼器由于阻尼力与体积过大而并不适用于滚筒洗衣机安装与控制,依据滚筒洗衣机悬挂 系统阻尼器力学性能以及磁流变液的材料特性和磁路设计原则,设计并制作了一个单出杆的剪切阀式磁流变阻尼器样 品,采用Instron 8800材料试验机对所设计的磁流变阻尼器进行特性试验,采集其在不同电流、频率和位移下的阻尼力。 采用MATLAB对实验数据进行处理,分析磁流变阻尼器的阻尼性能,结果表明该磁流变阻尼器设计是符合设计要求,可 用于滚筒洗衣机抑振控制策略的研究。     

Reference priors for a product of normal means when variances are unknown

The reference priors of Berger and Bernardo (1992) are derived for normal populations with unknown variances when the product of means is of interest. The priors are also shown to be Tibshirani's (1989) matching priors.