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31.
用一张计算全息图可产生锥面波,锥面波衍射图样的中心在空间是连续的,可作为直线基准。本文提出了提高锥面波直线准直精度的一种方法即空间滤波法。实验结果与理论分析一致。  相似文献   
32.
中华优秀传统文化是中华民族的精神命脉。推动中华优秀传统文化融入教材,对于建设培根铸魂、启智增慧的新时代中国特色高质量教材体系,培养具有高度文化自信的社会主义建设者与接班人具有重要意义。中华传统文化教材建设百年来经历了从“沉寂”到“复兴”的曲折发展历程,反映出中华优秀传统文化顽强的生命力。在中国特色社会主义新时代,中华优秀传统文化“进教材”既是一种注重文化传承与精神引领的知识建构,也是一种凝聚文化教育合力的协同发展。新时代中华优秀传统文化教材建设,应以习近平新时代中国特色社会主义思想为指导,坚持创造性转化与创新性发展的基本方向,探索教材基于新时代语境的现代化诠释、基于全球化语境的本土化编写的发展向度,塑造中华民族优秀文化形象,开发数字教材资源,让中华优秀传统文化渗透、融入教材。新时代中华优秀传统文化教材建设也应强化规范意识,积极规避“人文关怀式微”的价值危机、“学科视野窄化”的认识误区、“教材泛德育化”的理念偏差以及“教育逻辑缺失”的路向偏移等失范问题,增强责任之心,勇于担当作为,落实立德树人根本任务,在固本与创新中肩负起推动中华优秀传统文化传承和发展的历史使命。  相似文献   
33.
A Multivariate Model for Repeated Failure Time Measurements   总被引:1,自引:1,他引:0  
A parametric multivariate failure time distribution is derived from a frailty-type model with a particular frailty distribution. It covers as special cases certain distributions which have been used for multivariate survival data in recent years. Some properties of the distribution are derived: its marginal and conditional distributions lie within the parametric family, and association between the component variates can be positive or, to a limited extent, negative. The simple closed form of the survivor function is useful for right-censored data, as occur commonly in survival analysis, and for calculating uniform residuals. Also featured is the distribution of ratios of paired failure times. The model is applied to data from the literature  相似文献   
34.
Spatial thinking and spatial knowledge generation in decision-making are still not mature fields of study in planning research, despite these being crucial elements in addressing the issues of the twenty-first-century city. This article contributes to their understanding by exploring their interrelationships with spatial data usage. Through storylines, it analyzes the arguments that planning practitioners offer in support of infrastructure-led decisions in Arequipa (Peru), before and after spatial data usage. The article concludes that spatial data usage improve spatial thinking to different extents, yet suggests aligning spatial data generation and the inclusion of GIS-based spatial analyses with the spatial knowledge needed by routine planning practice.  相似文献   
35.
This article presents a framework for economic consequence analysis of terrorism countermeasures. It specifies major categories of direct and indirect costs, benefits, spillover effects, and transfer payments that must be estimated in a comprehensive assessment. It develops a spreadsheet tool for data collection, storage, and refinement, as well as estimation of the various components of the necessary economic accounts. It also illustrates the usefulness of the framework in the first assessment of the tradeoffs between enhanced security and changes in commercial activity in an urban area, with explicit attention to the role of spillover effects. The article also contributes a practical user interface to the model for emergency managers.  相似文献   
36.
Peer nominations, a central method for measuring peer relationships in developmental research, typically involve asking children or adolescents to choose peers who fit various criteria from an alphabetized roster of classmates or grade‐mates. Although such measures have been used for decades, very little research has investigated the effects of alphabetical name order on the number of nominations received by peers. This study collected peer nominations for 20 items among 607 eighth grade participants in two schools. Regression analyses showed that earlier name order significantly predicted higher nomination counts for eight of the items, and explained over 5 percent of the variance in four affective variables (friendship, acceptance, acquaintanceship, and received liking). Across variables, name order effects were negatively correlated with internal reliability of nominations, implying that order effects may be related to the consensus of the peer group. Name order also had a minimal effect on inter‐correlations among a subset of variables. Implications and concrete recommendations for controlling and reducing name order effects in future research are discussed.  相似文献   
37.
The cost of an uncontrolled incursion of invasive alien species (IAS) arising from undetected entry through ports can be substantial, and knowledge of port‐specific risks is needed to help allocate limited surveillance resources. Quantifying the establishment likelihood of such an incursion requires quantifying the ability of a species to enter, establish, and spread. Estimation of the approach rate of IAS into ports provides a measure of likelihood of entry. Data on the approach rate of IAS are typically sparse, and the combinations of risk factors relating to country of origin and port of arrival diverse. This presents challenges to making formal statistical inference on establishment likelihood. Here we demonstrate how these challenges can be overcome with judicious use of mixed‐effects models when estimating the incursion likelihood into Australia of the European (Apis mellifera) and Asian (A. cerana) honeybees, along with the invasive parasites of biosecurity concern they host (e.g., Varroa destructor). Our results demonstrate how skewed the establishment likelihood is, with one‐tenth of the ports accounting for 80% or more of the likelihood for both species. These results have been utilized by biosecurity agencies in the allocation of resources to the surveillance of maritime ports.  相似文献   
38.
A random effects model for analyzing mixed longitudinal count and ordinal data is presented where the count response is inflated in two points (k and l) and an (k,l)-Inflated Power series distribution is used as its distribution. A full likelihood-based approach is used to obtain maximum likelihood estimates of parameters of the model. For data with non-ignorable missing values models with probit model for missing mechanism are used.The dependence between longitudinal sequences of responses and inflation parameters are investigated using a random effects approach. Also, to investigate the correlation between mixed ordinal and count responses of each individuals at each time, a shared random effect is used. In order to assess the performance of the model, a simulation study is performed for a case that the count response has (k,l)-Inflated Binomial distribution. Performance comparisons of count-ordinal random effect model, Zero-Inflated ordinal random effects model and (k,l)-Inflated ordinal random effects model are also given. The model is applied to a real social data set from the first two waves of the national longitudinal study of adolescent to adult health (Add Health study). In this data set, the joint responses are the number of days in a month that each individual smoked as the count response and the general health condition of each individual as the ordinal response. For the count response there is incidence of excess values of 0 and 30.  相似文献   
39.
经典的绘画作品感染并打动观众,是通过视觉这一感官体验来完成的。因此,在今天展览越来越多、展厅越来越大的情况下,有一些人从简单的视觉体验出发,使“视觉冲击力”这一曾经只运用于设计领域的词汇,在绘画中泛滥,进而波及工笔画领域。文章根据中国传统工笔画的品评标准,结合现代工笔画的绘画创作实践,分析视觉冲击力与经典的工笔画之间的矛盾与联系:经典的工笔画具有一定的视觉冲击,但是具有“视觉冲击力”的工笔画不一定就是经典的画作,真正的经典作品必须具有崇高的审美本质,在经过岁月的检验后,才能焕发出像珍珠一样夺目的光彩。  相似文献   
40.
随着两岸关系和平发展的持续推进,这项战略已经产生了强大的溢出效应。影响所及,两岸关系结构、台湾民众对两岸关系的认知结构以及台湾岛内话语结构等都发生了根本性变化,这种局面对岛内政党政治的基本生态和未来发展趋势产生了较大影响,两个主要政党都针对环境的变化进行了一定的调整,以求适应台海局势的结构性变化,谋求未来更多的发展空间。  相似文献   
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