斜腿刚构桥几何布局的优化设计

采用数学规划的方法从静力和动力两方面对斜腿刚构桥的几何布局进行优化设计。静力优化设计的优化目标是截面截面应力平方均值最小，动力优化设计的优化目标是结构自振周期平方和最小。采用了直接搜索法寻优。通过算例可知，这两种优化设计方法均可行，且均为刚性设计。     

被遮蔽的"文革"叙事--从《玫瑰门》评论小史谈起

<玫瑰门>是铁凝20世纪80年代后期一部以"文革"为背景的重要作品,但从<玫瑰门>的评论小史可以看到,80年代后半期以来,评论界对"文革"主题的忽略与遮蔽是普遍的.其中对抽象人性的偏爱,导致评论界对铁凝等一些小说家揭开"文革"政治对人性阴暗面的催生和放大,与人性固有之丑陋的合谋真相这一努力,大多视而不见.这一情形与80年代中期开始形成的当代文学观密不可分,也与"瞻前"而非"顾后"的社会文化心理有着内在的联系.     

Generalized additive models for location, scale and shape

Summary.  A general class of statistical models for a univariate response variable is presented which we call the generalized additive model for location, scale and shape (GAMLSS). The model assumes independent observations of the response variable y given the parameters, the explanatory variables and the values of the random effects. The distribution for the response variable in the GAMLSS can be selected from a very general family of distributions including highly skew or kurtotic continuous and discrete distributions. The systematic part of the model is expanded to allow modelling not only of the mean (or location) but also of the other parameters of the distribution of y , as parametric and/or additive nonparametric (smooth) functions of explanatory variables and/or random-effects terms. Maximum (penalized) likelihood estimation is used to fit the (non)parametric models. A Newton–Raphson or Fisher scoring algorithm is used to maximize the (penalized) likelihood. The additive terms in the model are fitted by using a backfitting algorithm. Censored data are easily incorporated into the framework. Five data sets from different fields of application are analysed to emphasize the generality of the GAMLSS class of models.     

教育世界的特性

教育世界是教育科学研究的对象域。教育世界的特性是本质世界。教育世界的本质世界特性是以人的本质力量的外在表现物——哲学和各门学科知识体系为手段培养人性——人的本质。教育世界的本质特点就是本质教育。人的本质表现在责任、方法和美。教育世界的本质世界特性决定了教育科学属于本质科学。     

《历代微型小说选》词语札记

导致古代文学作品译注“望文生训”的原因之一,是在选择与确定词的语义时脱离了交际的语言环境,所以,《列异传》中的“生人气”、“略无”和《列女传》中的“便利”不应是“陌生人的气息”、“略微没有”和“方便”之义,而应该是“活人的气息”、“全无”和“有利可图”之义。     

心灵的失落与追寻——简论汉末男性诗人的女性同构心理

汉末男性诗人以女性为情感载体来抒写自我生命痛苦的写作用意,应与他们的处境和心态密切相关。在混乱的政局中经历了期盼、失望、绝望的心路历程之后,他们的心态发生了很大变化,具有与女性心理同构的新特点。这恰恰彰显了汉末男性诗人摆脱心灵困境时的自我突围意识。     

《汉语拼音方案》的制定、传播与应用

继承了我国传统的直音、反切等方法以及西方学者的拉丁字母式拼音方法，《汉语拼音方案》作为新中国文字改革的一大成果诞生了。从制定到推行与传播，《汉语拼音方案》在具体应用过程中产生了一些问题需要尽快得到解决，以便《汉语拼音方案》能够为构建和谐语言生活发挥更大的促进作用。     

HEAVY-TAILED-DISTRIBUTED THRESHOLD STOCHASTIC VOLATILITY MODELS IN FINANCIAL TIME SERIES

To capture mean and variance asymmetries and time‐varying volatility in financial time series, we generalize the threshold stochastic volatility (THSV) model and incorporate a heavy‐tailed error distribution. Unlike existing stochastic volatility models, this model simultaneously accounts for uncertainty in the unobserved threshold value and in the time‐delay parameter. Self‐exciting and exogenous threshold variables are considered to investigate the impact of a number of market news variables on volatility changes. Adopting a Bayesian approach, we use Markov chain Monte Carlo methods to estimate all unknown parameters and latent variables. A simulation experiment demonstrates good estimation performance for reasonable sample sizes. In a study of two international financial market indices, we consider two variants of the generalized THSV model, with US market news as the threshold variable. Finally, we compare models using Bayesian forecasting in a value‐at‐risk (VaR) study. The results show that our proposed model can generate more accurate VaR forecasts than can standard models.     

Horwitz's rule, transforming both sides and the design of experiments for mechanistic models

Summary. The paper develops methods for the design of experiments for mechanistic models when the response must be transformed to achieve symmetry and constant variance. The power transformation that is used is partially justified by a rule in analytical chemistry. Because of the nature of the relationship between the response and the mechanistic model, it is necessary to transform both sides of the model. Expressions are given for the parameter sensitivities in the transformed model and examples are given of optimum designs, not only for single-response models, but also for experiments in which multivariate responses are measured and for experiments in which the model is defined by a set of differential equations which cannot be solved analytically. The extension to designs for checking models is discussed.     

Real nonparametric regression using complex wavelets

Summary.  Wavelet shrinkage is an effective nonparametric regression technique, especially when the underlying curve has irregular features such as spikes or discontinuities. The basic idea is simple: take the discrete wavelet transform of data consisting of a signal corrupted by noise; shrink or remove the wavelet coefficients to remove the noise; then invert the discrete wavelet transform to form an estimate of the true underlying curve. Various researchers have proposed increasingly sophisticated methods of doing this by using real-valued wavelets. Complex-valued wavelets exist but are rarely used. We propose two new complex-valued wavelet shrinkage techniques: one based on multiwavelet style shrinkage and the other using Bayesian methods. Extensive simulations show that our methods almost always give significantly more accurate estimates than methods based on real-valued wavelets. Further, our multiwavelet style shrinkage method is both simpler and dramatically faster than its competitors. To understand the excellent performance of this method we present a new risk bound on its hard thresholded coefficients.