基于学生能力提高的混合式实验课教学模式研究

实验是理论课程的验证和深化,对提高学生知识和技能、创新和探索能力等方面有着不可替代的作用.在我国大力实施课程改革之际,结合先进的混合式教学理论与实践,对《城市广场规划设计》实验课教学模式改革进行探索,为提高学生能力、拓展思政教学手段、实施开放式教学提供理论基础.     

绿色增长下的导向性技术创新选择研究

针对如何正确引导 GHG 排放的气候反馈经济损失下导向性技术创新，以实现长期的绿色增长这一问题，基于 DICE 模型，重构导向性技术创新不同的动力要素及其与气候变化之间的内生关系，建立了可体现绿色增长“均衡性”、“包容性”和“可持续性”的非线性最优控制模型。数值仿真结果显示: 气候反馈经济损失不容小觑; 偏于生产的绿色技术创新导向下社会生产力强劲但存在气候环境恶化风险，偏于减排的绿色技术创新导向下气候反馈经济损失小但存在增长动力匮乏风险，二者虽均可实现长期的绿色增长，但中性的绿色技术创新导向会更稳妥; 偏于生产的绿色技术创新导向下人均消费变化率在短期内会显著提升。     

基于变系数分位点回归的金砖四国金融稳定分析

金融不稳定性累积到一定程度就会引发金融危机,而新兴市场作为世界经济发展的重要增长点,同时也是金融危机爆发的重灾区.因此,新兴市场金融稳定性的研究至关重要.本文基于新兴市场代表国家——金砖四国(中国,俄罗斯,印度,巴西)的主要综合股指对金融稳定性进行了实证研究.与传统金融稳定性的研究方法不同,本文考虑系统性冲击在正常和极端市场下对不同国家金融市场的影响.首先应用分位数回归模型对金砖四国的金融稳定性进行检验,进而基于变系数分位数模型研究系统性冲击对金融市场稳定性的影响随时间变化的趋势,对金融稳定性进行了时变分析.实证结果表明,金砖四国都具有某种程度的金融不稳定性,近期中国和巴西在5%分位点处的金融不稳定性受系统性冲击的影响相对于印度和俄罗斯更加剧烈.     

基于OBE教育理念的土木工程专业英语教学改革实践

为提高土木工程专业学生的英语应用能力和《土木工程专业英语》课程的教学效果，本次教改实践以OBE（成果导向教育）教育理念为教改指导思想，以土木工程专业英语教学为教改对象，设计了土木工程专业英语教学的教学内容、教学组织和教学评价等教学环节，在河北工程大学土木工程专业学生中进行了教改实践。教改实践结果表明，基于OBE的土木工程专业英语教学模式在提升土木工程专业学生英语应用能力方面具有很好的效果。本次教改实践的成果值得本校其他工科专业和其他兄弟院校借鉴。     

Deterministic construction of compressed sensing matrices based on semilattices

A central problem in compressed sensing is the construction of sensing matrices. In this paper, we show how to construct sensing matrices by using semilattices, and give many examples of sensing matrices constructed from specific semilattices. Moreover, we show that the new construction for some examples with small parameters gives better sensing matrices compared with previously known constructions.     

Species richness,phylogenetic and functional structure of bird communities in Chinese university campuses are associated with divergent variables

University campus is an important component of urban landscapes for biodiversity conservation. However, to our knowledge no study has quantitatively assessed the diversity and structure of bird communities in Chinese university campuses, especially from phylogenetic and functional perspectives. Here, for the first time we linked species richness, phylogenetic structure and body mass structure of campus bird communities with contemporary climate, glacial-interglacial climate change, altitudinal range, population density around campus, area and age of campus to test their associations. We found 393 bird species in 38 university campuses (29% of all Chinese bird species, two species are endangered, four species are vulnerable, and 33 species are near threatened). The variables significantly correlated with campus bird species richness, phylogenetic structure and body mass structure were altitudinal range and mean annual precipitation, glacial-interglacial anomaly in temperature, and altitudinal range, respectively. In particular, there were more species in steeper and wetter campuses, more young species clustered in campuses with stable glacial-interglacial climate, and more species with smaller body size in steeper campuses. Our study highlights the importance of considering both phylogenetic and functional information for biodiversity conservation in urban ecosystems.     

Chinese youth performing identities and navigating belonging online

This paper examines the experiences of belonging of young Chinese internet users through an analysis of their online identity practices. Drawing on a qualitative research project about online citizenship practices of 31 young Chinese citizens from mainland China, I explore their experiences of belonging on two online platforms (Weibo and WeChat) and the identities formed and sustained through these experiences. The results show that young people experience different senses of belonging in different social media spaces. Their strategies in navigating these experiences are informed by (a) their perceptions of online spaces as private or public, and (b) using online identity performance as a supplement to or escape from identities in physical life. I argue that young Chinese internet users experience different senses of belonging by flexibly appropriating the affordances of social media platforms for communication and networking; these senses of belonging play a key role in forming and sustaining their identities, and are crucial for their wellbeing.     

杜甫《登高》诗中的乐观主义精神探微

杜甫写于唐大历二年(767年)秋天的《登高》诗,虽是其晚年凄凉与孤独生活状态的真实写照,但诗中却充满着令人激动的气势.这种气势不仅源于杜甫对登高文学传统的继承,亦是其晚年面对迁逝之感时昂扬生命意识的展现.除了感时伤事,诗中还深刻蕴含着杜甫晚年的壮阔情怀以及乐观主义精神,这种精神与夔州相对安定的生活有着密切关联,更是其儒家思想的重要体现.     

从背井离乡到创新创业 ——兼论互联网使用对创业的作用

文章利用2016年中国劳动力动态调查(CLDS)数据探讨了外出务工经历对农民创业的影响.实证分析表明,外出务工经历显著提高了农民创业概率1.67％.使用工具变量法和倾向得分匹配法对内生性进行弱化后,上述结果仍旧稳健.并且发现异质性外出务工经历中,企业务工经历对创业行为并无显著影响,而自由工作、个体工商户等非企业工作经历则显著提升了农民创业概率,这为不同类型的外出务工经历对创业的影响提供了新的经验证据,打开了外出务工经历的"黑匣子".对外出务工影响创业的机制进一步探讨发现,外出务工经历会通过社会资本、物质资本和人力资本三个渠道提高农户创业概率,而创业动机并非其影响机制.同时,文章发现,互联网使用在一定程度上与外出务工具有类似的功能,对外出务工经历存在一定的替代效应.最后,文章研究表明外出务工经历对本地创业具有显著影响,而对外地创业的影响则不显著;相较于雇主创业,外出务工经历对自雇创业具有显著的正向影响.