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1.
近日对我国著名电子光学和光电子成像专家周立伟院士进行了访谈。访谈中,周院士首先分享了自己学习英语和俄语的经历,强调了自主学习能力的重要性;其次,周院士详细论述了外语教学,尤其是英语教学的必要性,指出英语能力与科学研究紧密相关,英语教学不可或缺;之后周院士分析了研究生在英语学习和科学研究方面存在的问题,并讨论了大学中开设人文课程的迫切性;最后,周院士对上理工师生提出了建议与期望。  相似文献   
2.
志愿服务乡村是社会参与人才振兴战略的重要方式,大学生在其中承担着重要角色。“乡愁文化”和“社会理性”是大学生志愿服务乡村缘由所在;性别、年级、学校类型、了解程度和志愿组织对大学生志愿服务乡村有显著影响。大学生志愿服务的着力点在于智力支持且具有文教活动倾向性,但也存在意愿与行动脱节、认知流于表面、能动性不强、缺乏思想引领以及对小微志愿组织的支持缺位等问题。乡愁文化嵌入大学文化、引入激励机制、打造志愿组织“大家庭”、牢守宣传育人“主阵地”、强化智力支持优势、补齐理论技能短板、关爱“小微组织”成长、构建“三位一体”支撑体系等可有效优化大学生志愿服务乡村。  相似文献   
3.
Damage models for natural hazards are used for decision making on reducing and transferring risk. The damage estimates from these models depend on many variables and their complex sometimes nonlinear relationships with the damage. In recent years, data‐driven modeling techniques have been used to capture those relationships. The available data to build such models are often limited. Therefore, in practice it is usually necessary to transfer models to a different context. In this article, we show that this implies the samples used to build the model are often not fully representative for the situation where they need to be applied on, which leads to a “sample selection bias.” In this article, we enhance data‐driven damage models by applying methods, not previously applied to damage modeling, to correct for this bias before the machine learning (ML) models are trained. We demonstrate this with case studies on flooding in Europe, and typhoon wind damage in the Philippines. Two sample selection bias correction methods from the ML literature are applied and one of these methods is also adjusted to our problem. These three methods are combined with stochastic generation of synthetic damage data. We demonstrate that for both case studies, the sample selection bias correction techniques reduce model errors, especially for the mean bias error this reduction can be larger than 30%. The novel combination with stochastic data generation seems to enhance these techniques. This shows that sample selection bias correction methods are beneficial for damage model transfer.  相似文献   
4.
Environmental scanning is a broadly defined concept, having first received attention from scholars in the late 1960s. Over the years a number of similar and overlapping constructs have emerged in management literature. The aim of this study, via a systematic review and thematic analysis of relevant empirical research, is to consolidate foundation environmental scanning knowledge, demonstrate how scanning research has developed and fragmented over time, and propose an agenda for future research. The first contribution of our review is a new typology of environmental scanning research made up of five discrete research views, which provides a more comprehensive and contemporary overview of the field than previous studies. The second is a proposed agenda for future research that explicitly acknowledges the role of technology, an area that is presently underdeveloped in foundation scanning literature. The third contribution is to signpost future directions for research on scanning and organisational performance using a number of theoretical perspectives. The overall outcome of our review is to move scanning research on from increasingly incremental contributions concerned with context to a place where the changing role of technology and the mechanisms through which environmental scanning contributes to competitive advantage can be more thoroughly understood.  相似文献   
5.
以高中生为被试对象,以大陆漂移论为素材,研究外部视觉情绪设计对多媒体学习的影响。结果表明,接受情绪设计组(实验组)的积极情绪显著高于中性组(对照组);实验组与对照组内在认知负荷、相关认知负荷均无显著差异,外在认知负荷小于对照组;实验组保持测验成绩显著高于对照组,迁移测验成绩无差异。同时,外部视觉情绪设计能显著提高多媒体学习效果。外部视觉情绪设计的实验设计突破了已有研究300s学习素材的诱发时间,拓展了多媒体学习情绪设计的内涵。  相似文献   
6.
BackgroundMidwife-led continuity of care has substantial benefits for women and infants and positive outcomes for midwives, yet access to these models remains limited. Caseload midwifery is associated with professional satisfaction and lower burnout, but also impacts on work-life boundaries. Few studies have explored caseload midwifery from the perspective of midwives working in caseload models compared to those in standard care models, understanding this is critical to sustainability and upscaling.AimTo compare views of caseload midwifery – those working in caseload models and those in standard care models in hospitals with and without caseload.MethodsA national cross-sectional survey of midwives working in Australian public hospitals providing birthing services.FindingsResponses were received from 542/3850 (14%) midwives from 111 hospitals – 20% worked in caseload, 39% worked in hospitals with caseload but did not work in the model, and 41% worked in hospitals without caseload. Regardless of exposure, midwives expressed support for caseload models, and for increased access to all women regardless of risk. Fifty percent of midwives not working in caseload expressed willingness to work in the model in the future. Flexibility, autonomy and building relationships were positive influencing factors, with on-call work the most common reason midwives did not want to work in caseload.ConclusionsThere was widespread support for and willingness to work in caseload. The findings suggest that the workforce could support increasing access to caseload models at existing and new caseload sites. Exposure to the model provides insight into understanding how the model works, which can positively or negatively influence midwives’ views.  相似文献   
7.
体验式学习的内涵随着时代的发展而逐渐丰富和深化,但无论其如何演变,直接经验和反思始终是体验式学习这一概念的内核。体验式学习理念渗透于美国教育文化之中。具体表现在:小学阶段的教育以学生的真实感知为基础,注重为学生提供真实体验的机会和激发学生的学习兴趣;中学尤其是高中阶段的教育以学生的真实体验为基础,注重为学生提供在新情境中检验所学知识的机会,注重学生知识、技能的内化吸收。美国中小学体验式学习的实施经验可为我国基础教育课程改革提供如下启示:(1)进一步树立和推广体验式学习理念;(2)创设学生进行真实体验的教学环境;(3)注重实施基于学生体验式学习的表现性评价。  相似文献   
8.
地区收入、食品价格与恩格尔系数   总被引:2,自引:0,他引:2  
陈梦根 《统计研究》2019,36(6):28-41
本文以2016年我国31个省级地区截面数据为样本,构建扩展模型考察恩格尔系数与收入、食品价格之间的关系。研究发现,恩格尔系数与地区收入存在显著的负相关性,纳入食品价格后收入对恩格尔系数的影响变得更为显著,二者关系满足恩格尔定律。恩格尔系数和以地区食品价格平价代表的食品价格之间显著正相关,若再考虑其他因素,则食品价格对恩格尔系数的影响会稍有减弱。进一步将食品区分为生活必需型食品与非生活必需型食品,测算得到的基本恩格尔系数、高阶恩格尔系数与收入之间仍呈负相关关系,但与基本恩格尔系数相比,高阶恩格尔系数与收入之间的负相关性更弱。恩格尔系数受生活必需型食品价格的影响强于非生活必需型食品价格的影响,基本恩格尔系数主要受生活必需型食品价格的影响,而高阶恩格尔系数同时受到两类食品价格的影响。  相似文献   
9.
高敏雪 《统计研究》2021,38(10):3-11
本文结合国际国内研究动态分层次归纳、阐释当前国民经济核算的研究议题。具体包括:以国民账户体系2008版(SNA-2008)为起点的前沿研究,SNA中心框架的灵活运用研究,接驳中国国民经济核算体系(CSNA)及其实务的优化和创新研究,国民经济核算数据的综合应用研究。最后针对中国当前国民经济核算研究方法中存在的一些倾向性问题做讨论,比如是否过分关注与GDP的关联, 如何充分发挥卫星账户的作用等。  相似文献   
10.
In this paper, two new multiple influential observation detection methods, GCD.GSPR and mCD*, are introduced for logistic regression. The proposed diagnostic measures are compared with the generalized difference in fits (GDFFITS) and the generalized squared difference in beta (GSDFBETA), which are multiple influential diagnostics. The simulation study is conducted with one, two and five independent variable logistic regression models. The performance of the diagnostic measures is examined for a single contaminated independent variable for each model and in the case where all the independent variables are contaminated with certain contamination rates and intensity. In addition, the performance of the diagnostic measures is compared in terms of the correct identification rate and swamping rate via a frequently referred to data set in the literature.  相似文献   
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