Design selection for strong orthogonal arrays

Strong orthogonal arrays (SOAs) were recently introduced and studied as a class of space‐filling designs for computer experiments. An important problem that has not been addressed in the literature is that of design selection for such arrays. In this article, we conduct a systematic investigation into this problem, and we focus on the most useful SOA(n,m,4,2 + )s and SOA(n,m,4,2)s. This article first addresses the problem of design selection for SOAs of strength 2+ by examining their three‐dimensional projections. Both theoretical and computational results are presented. When SOAs of strength 2+ do not exist, we formulate a general framework for the selection of SOAs of strength 2 by looking at their two‐dimensional projections. The approach is fruitful, as it is applicable when SOAs of strength 2+ do not exist and it gives rise to them when they do. The Canadian Journal of Statistics 47: 302–314; 2019 © 2019 Statistical Society of Canada     

The context of employment discrimination: interpreting the findings of a field experiment

Although field experiments have documented the contemporary relevance of discrimination in employment, theories developed to explain the dynamics of differential treatment cannot account for differences across organizational and institutional contexts. In this article, I address this shortcoming by presenting the main empirical findings from a multi‐method research project, in which a field experiment of ethnic discrimination in the Norwegian labour market was complemented with forty‐two in‐depth interviews with employers who were observed in the first stage of the study. While the experimental data support earlier findings in documenting that ethnic discrimination indeed takes place, the qualitative material suggests that theorizing in the field experiment literature have been too concerned with individual and intra‐psychic explanations. Discriminatory outcomes in employment processes seems to be more dependent on contextual factors such as the number of applications received, whether requirements are specified, and the degree to which recruitment procedures are formalized. I argue that different contexts of employment provide different opportunity structures for discrimination, a finding with important theoretical and methodological implications.     

Media Disaster Reporting Effects on Public Risk Perception and Response to Escalating Tornado Warnings: A Natural Experiment

Previous research has evaluated public risk perception and response to a natural hazards in various settings; however, most of these studies were conducted either with a single scenario or after a natural disaster struck. To better understand the dynamic relationships among affect, risk perception, and behavioral intentions related to natural disasters, the current study implements a simulation scenario with escalating weather intensity, and includes a natural experiment allowing comparison of public response before and after a severe tornado event with extensive coverage by the national media. The current study also manipulated the display of warning information, and investigated whether the warning system display format influences public response. Results indicate that (1) affect, risk perception, and behavioral intention escalated as weather conditions deteriorated, (2) responses at previous stages predicted responses at subsequent stages of storm progression, and (3) negative affect predicted risk perception. Moreover, risk perception and behavioral intention were heightened after exposure to the media coverage of an actual tornado disaster. However, the display format manipulation did not influence behavioral responses. The current study provides insight regarding public perception of predisaster warnings and the influence of exposure to media coverage of an actual disaster event.     

素质教育对化学教师素质的要求

化学教师必须具备良好的思想道德素质 ,丰富的化学专业知识和较全面的知识技能、丰富的教育理论水平以及探索创新的精神才能适应新世纪的挑战     

ALL-BIAS DESIGNS FOR POLYNOMIAL SPLINE REGRESSION MODELS

Polynomial spline regression models of low degree have proved useful in modeling responses from designed experiments in science and engineering when simple polynomial models are inadequate. Where there is uncertainty in the number and location of the knots, or breakpoints, of the spline, then designs that minimize the systematic errors resulting from model misspecification may be appropriate. This paper gives a method for constructing such all‐bias designs for a single variable spline when the distinct knots in the assumed and true models come from some specified set. A class of designs is defined in terms of the inter‐knot intervals and sufficient conditions are obtained for a design within this class to be all‐bias under linear, quadratic and cubic spline models. An example of the construction of all‐bias designs is given.     

中学化学实验研究选题探讨

中学化学实验研究的关键问题是如何选择研究课题。应从中学化学教学的需要、中学化学实验研究的内容、中学化学实验的发展趋势以及中学化学实验教学改革等方面来选择研究课题。     

物理化学授课体系改革与研究

培养高素质、综合型人才的关键是教育.针对物理化学课程的特点,对授课体系进行了改革、研究,对课程内容进行重组,设计,构筑了有利于高素质人才培养的课堂教学模式.     

开设化学设计性实验的探索与实践

阐述开设设计性实验的意义,并在实践的基础上,给出了开设化学设计性实验的方案,总结了开设设计性实验的体会。     

材料化学与高技术新材料和信息材料

材料化学的研究对象是物质的组成、制备、结构与性能的变化规律及其应用。它强调现代精细材料合成与光电技术相互结合,深入系统地研究各种材料制备工艺及其与材料性能的关系,发展新型功能材料的人工设计技术,采用先进的实验技术和方法,研究和发展具有特定微结构和性能的新型功能材料。高技术新材料和信息材料的发展离不开材料化学,反过来,材料化学的发展进一步推动高技术新材料和信息材料的发展和进步。     

大学计算机专业“基础原理”课的教学探讨

本文针对现代大学生学习计算机专业“基础原理”课程存在的种种客观问题,通过分析这些问题找出其中原因,并介绍对这些问题所采取的解决方案。教学实践表明,这些方案对学生学习“基础原理课”起到了较好的效果,提高了这类课程的教学质量。