关于不定方程(sum from X=1 to n(x~y))~5=(sum from X=1 to n(x~z))~t

本文利用∑nk=1kp的形式表达式解决了不定方程(∑nx=1xy)s=(∑nx=1xz)t.     

新议清朝人口剧增的原因及影响

清朝人口剧增包括多方面原因,既有社会政治稳定、社会经济发展等一般原因,也有历史遗留人口基数比较大、人口统计范围扩大、高产农作物大量种植等特殊原因。赋税制度的变革在刺激人们生育的同时也使人口统计的真实性加强。庞大的人口既给清朝社会经济发展带来了负面影响,也提升了清朝的综合国力,转变了人们的生育观念,更使得大量的人口为了生存而转向工商业领域。     

Students’ age and noncognitive traits predict writing self-efficacy and motivation

The present study explored the relations of students’ age and noncognitive traits (grit, growth mindset, and college self-efficacy) on writing self-efficacy and writing motivation. Participants (N = 457) wrote a short reflection in response to a quote, after which they evaluated similar responses, purportedly written by their peers, that were either exemplary or poor. Participants who read the exemplary essays were less likely to believe they could write as well as their peers (writing self-efficacy) and less likely to write a second essay (writing motivation), demonstrating a discouragement by peer excellence effect. Grit, growth mindset, and college self-efficacy were all positive correlates of writing self-efficacy. Writing self-efficacy, in turn, predicted the willingness to write another essay. Older students reported higher levels of writing self-efficacy and exhibited greater writing motivation. Older students also reported higher levels of grit, college self-efficacy, and growth mindset. A parallel mediation analysis revealed an indirect effect of college self-efficacy on the relation between age and writing self-efficacy. These results suggest that educators should judiciously model the works of students’ exemplary peers and foster noncognitive traits that improve writing self-efficacy. The results also suggest that older students are more receptive to writing.     

Goal Setting,Academic Reminders,and College Success: A Large-Scale Field Experiment

This article presents an independent large-scale experimental evaluation of two online goal-setting interventions. Both interventions are based on promising findings from the field of social psychology. Approximately 1,400 first-year undergraduate students at a large Canadian university were randomly assigned to complete one of two online goal-setting treatments or a control task. In addition, half of treated participants were offered the opportunity to receive follow-up goal-oriented reminders through e-mail or text messages to test a cost-effective method for increasing the saliency of treatment. Across all treatment groups, we observed no evidence of an effect on grade point average, course credits, or second-year persistence. Our estimates are precise enough to discern a 7% standardized performance effect at a 5% significance level. Our results hold by subsample, for various outcome variables, and across a number of specifications.     

大学生心理健康评价标准的积极模式

对国内外不同学派的心理健康观以及相关研究进行理论分析,从积极心理学的角度提出了适合于不同文化背景的、评价大学生心理健康的6条基本标准,既自我接纳、积极的人际关系、自主性、环境控制与利用、生活目标和个体成长。     

"全国统一考试是国家意志的体现"这一提法的回顾

"全国统一考试是国家意志的体现",这一提法既有积极意义,也有历史局限,对以科学发展观来审视统一考试制度的改革完善、兴废、发展,有所裨益。     

四阶常微分方程的正周期解

讨论四阶常微分方程u(4)(t)+a(t)u(t)=f(t,u(t)),t∈R周期边值问题,利用锥上不动点指数理论,获得了正周期解的存在性及多重性结果.     

Inclusion of pupils with ADHD symptoms in mainstream classes with PBS

Inclusion is never only a practical issue of placement. School-wide systemic change, together with well-functioning, multi-tiered support, can promote the inclusion of all pupils. This paper draws on research conducted in two mainstream primary schools in Finland. The primary focus was to gain insight into practical solutions to facilitate the inclusion of pupils with attention-deficit hyperactivity disorder (ADHD) in mainstream teaching. Using an experimental, multiple-baseline, single-case design, we examined the effects of Check-in Check-out (CICO) support on changes in the behaviour of two pupils who displayed ADHD-type behaviours. The key features of CICO are brief morning and afternoon meetings with an adult, the use of a daily report card, regular positive feedback during the day, and parental involvement. This study examined if behavioural gains made during the implementation of CICO support can be maintained. Visual data analysis revealed differences in two CICO-ending strategies on maintenance in pupils with ADHD symptoms. The results suggest that consistent universal positive behaviour support systems together with additional behavioural support can facilitate the successful inclusion of pupils observed by teachers to have even severe disruptive behaviours in a mainstream learning environment.     

About,for, in or through entrepreneurship in engineering education

Engineering competences form a potential basis for entrepreneurship. There are pressures to find new approaches to entrepreneurship education (EE) in engineering education, as the traditional analytical logic of engineering does not match the modern view of entrepreneurship. Since the previous models do not give tangible enough tools on how to organise EE in practice, this article aims to develop a new framework for EE at the university level. We approach this aim by analysing existing scientific literature complemented by long-term practical observations, enabling a fruitful interplay between theory and practice. The developed framework recommends aspects in EE to be emphasised during each year of the study process. Action-based learning methods are highlighted in the beginning of studies to support students’ personal growth. Explicit business knowledge is to be gradually increased only when professional, field-specific knowledge has been adequately accumulated.     

Experiencing the outdoors: peak episodes are interesting but the memories are pleasant

Inspired by the distinction between hedonic and eudaimonic feeling states, we examined the distinction between feelings of pleasure and interest as well as subsequent motivation related to participation in outdoor events among students of physical education (n = 64) in a Norwegian university college. The students reported on their experiences during two three-day trips: one coastal trip and one ski trip. The participants also reported how they felt about the trips after one week and after one month. The feelings of pleasure and interest were contrasted by analysing mean scores, factor loadings and regression coefficients. Momentary experiences typically showed higher scores for feelings of interest than for feelings of pleasure, but there were some exceptions. The interest-higher-than-pleasure tendency tended to disappear for remembered experiences. The results support the notion that pleasure and interest are separable emotions with distinct functions, but our findings are far from conclusive. Implications for outdoor leadership and future research are discussed.