工程制图教学中如何培养学生空间想象能力

从3个方面论述了如何培养学生空间想象能力,一个方面是观察能力的培养,另一个方面是形象思维能力的培养以及创造性思维能力的培养。     

对当前报纸版面设计误区的观察与思考

在日趋激烈的竞争中,一些报纸过分夸大和强调“形式美”,在缺乏理性思维和正确审美指导的情况下,走入了版面设计的误区。其具体表现为缺乏新闻性,缺乏导向性,缺乏风格与个性,包装的过度性,等等。版面代表报纸的形象,其重要性不言而喻,版面的设计应该与时俱进,提倡改革和创新。只有坚持正确的方向,进行理性的思考,才能使我们新时期报业的版面设计工作走出误区,走向成熟,使版面真正成为向读者传达信息,与读者进行交流,为读者提供享受的平台。     

Estimation of frequencies of sinusoids in the presence of noise

A method is proposed and developed for estimating the frequencies of K sinusoids given the sum of these sinusoids in Gaussian noise. Attention is focused on the properties of these estimators when the observation time is short, the separation between frequencies is small, and the signal-to-noise ratio is high. The estimators are shown to be approximately unbiased and approximately normally distributed. The covariance matrix is also calculated. Relatively simple bounds on the variance of the estimators are found.     

关于书法创作中的取象

书法家把从大自然中获得的美感,概括曲折地反映到书法创作中来,使其作品纵横有象,物象生动,从而形成自己的书法风格,这就是书法创作中的取象。书法取象有一定的概括性和寄托性。取象是产生书法意境的先决条件,它决定书法作品的格调。书法创作不仅要通过观察和领悟的途径,还必须运用形象思维,形象思维在书法创作中的主要表现是联想和想象。     

Local Influence Analysis in AB–BA Crossover Designs

The aim of this article is to develop methodology for detecting influential observations in crossover models with random individual effects. Various case‐weighted perturbations are performed. We obtain the influence of the perturbations on each parameter estimator and on their dispersion matrices. The obtained results exhibit the possibility to obtain closed‐form expressions of the influence using the residuals in mixed linear models. Some graphical tools are also presented.     

Regression analysis of recurrent events data with incomplete observation gaps

For analyzing recurrent event data, either total time scale or gap time scale is adopted according to research interest. In particular, gap time scale is known to be more appropriate for modeling a renewal process. In this paper, we adopt gap time scale to analyze recurrent event data with repeated observation gaps which cannot be observed completely because of unknown termination times of observation gaps. In order to estimate termination times, interval-censored mechanism is applied. Simulation studies are done to compare the suggested methods with the unadjusted method ignoring incomplete observation gaps. As a real example, conviction data set with suspensions is analyzed with suggested methods.     

谈写作中的艺术观察

观察是一种有目的、有计划、比较持久的知觉活动,观察活动是整个写作过程的开始。写作观察可分为客观观察和艺术观察,艺术观察是高于客观观察的一种审美观察,有其自身特殊的属性,体现出审美主体的独到发现和审美情感,并且也是艺术形象的重要构成成分。艺术观察主要体现在两个方面,即敏锐地捕捉事物的特征和深入透析人物的心理。     

Dynamic generalized extreme value modeling via particle filters

This article addresses how particle filters compare to MCMC methods for posterior density approximations of a model that allows for a dynamic state with fixed parameters and where the observation equation is nonlinear. This is a problem that was not been well studied in the specialized literature. We prove that these state and parameter estimations can be achieved via particle filter methods without the need of more expensive Forward Filtering Backward Sampling (FFBS) simulation. Estimation of a time-varying extreme value model via the generalized extreme value distribution is considered using these particle filter methods and compared to a MCMC algorithm that involves a variety of Metropolis-Hastings steps. We illustrate and compare the different methodologies with simulated data and some minimum daily stock returns occurring monthly from January 4, 1990 to December 28, 2007 using the Tokyo Stock Price Index (TOPIX).     

Estimation for Discretely Observed Small Diffusions Based on Approximate Martingale Estimating Functions

Abstract.  We consider an asymptotically efficient estimator of the drift parameter for a multi-dimensional diffusion process with small dispersion parameter ɛ . In the situation where the sample path is observed at equidistant times k / n , k  = 0, 1, …,  n , we study asymptotic properties of an M -estimator derived from an approximate martingale estimating function as ɛ tends to 0 and n tends to ∞ simultaneously.     

《水浒》忠义思想的纵向考察

《水浒传》书名全称为“忠义水浒传”,忠义思想是作家要表现的重要思想,基本含义就是忠君义友,源于汉代以后儒家的忠义观。小说通过对招安、征辽、征方腊三大事件的处理和对宋江形象的修正,来表现忠君思想,部分地达到了目的,但忠君思想与农民起义互不相容。《水浒传》对义友的表现远比忠君成功,主要受惠于同一题材的前代作品。作者在处理义与忠、孝的关系方面,也出现了矛盾现象。