Dynamic analysis of landing autonomous underwater vehicle

In autonomous underwater vehicles(AUVs) the onboard power used to complete missions is limited.To solve this problem,a landing AUV has been designed,which conserves energy by sitting on the seafloor while monitoring the ocean.In order to study the dynamic behaviors for better control of the AUV,the dynamic analysis of the landing AUV is presented in this paper.Based on the momentum theorem and the angular momentum theorem,the dynamic model of the landing AUV is derived.The simulations of rectilinear motion,rotary motion and helix motion indicate the dynamic behaviors of the AUV.The ocean experiments validate the dynamic model presented in this paper.The experiments also verify that the landing AUV can work for a longer time than common AUVs.     

Banach不动点定理的推广定理及其应用

将Banach不动点定理推广到一类压缩型广义不动点定理,并介绍Banach不动点定理的变换形式在数学建模中的应用,来说明用不动点定理可以处理一些传统方法比较难解决的问题,进一步体现不动点理论应用的广泛性.     

Impact of online support for teachers’ open-ended questioning in pre-k science activities

We examined the effects of teacher supports in enhancing teachers’ open-ended questioning in pre-k activities. The blended teacher supports included online video demonstrations of questioning techniques and companion workshop activities. Twenty-five teachers received the blended supports while the control group did not. The data consisted of classroom video observations, teacher surveys, and teachers’ access time to teacher supports. Our quantitative analyses revealed that the treatment group teachers used more open-ended questions than the control group teachers. The students in the treatment group used a greater number of different words and complex sentences than those in the control group.     

我国研究生教育对经济增长的贡献率——基于1996—2009年省际面板数据的实证研究

利用1996-2009年省际面板数据,对我国研究生教育对经济增长的贡献率进行实证分析,结果发现:1996-2009年间,我国研究生教育对经济增长具有正向促进作用,年均拉动GDP增长0.46个百分点,对GDP年均增长的贡献率为4.11%;研究生教育或者说知识资本和人力资本对经济增长的贡献率远低于物质资本的贡献率;忽略研究生教育的作用将会导致高估物质资本而低估人力资本的作用;我国研究生教育对经济增长的影响作用弱于美国研究生教育的影响作用。     

浅析“反思型”教师

反思型教师是对经验型教师的超越,成为一名反思型教师,是教师成长与发展的必由之路,也是新课程改革的需要。自我反思与集体反思相结合、阅读相关的理论文献、加强师生间的交流对话和有效利用blog与电子档案袋是成为一名反思型教师的有效途径。     

数学建模对高职院校学生应用与创新能力培养的研究及实践

文章依据开展数学建模活动的实践经验,阐述了数学建模对高职院校学生应用与创新能力培养的重要意义,探讨了如何通过数学建模活动培养高职学生的应用与创新能力,并对高职院校开展数学建模提出了几点思考。     

A Technique for the Construction of a Teacher-Training Curriculum

ABSTRACT

Historically, students who fail to graduate from secondary school are considered as a single category of school dropouts. However, emerging literature indicates that there may be multiple subgroups of high school dropouts, termed a dropout typology. The authors’ purpose was to assess the extent to which a typology of dropouts was present in a large national dataset and to estimate the influence of the known covariates of dropping out on each of the subgroups. A growth mixture model was estimated using the Education Longitudinal Study 2002 (National Center for Education Statistics, n.d.) dataset and noncumulative grade point average during the first 3 semesters of high school. The model identified 2 main subgroups associated with dropping out, which accounted for 24.6% of the sample but contained 91.8% of the dropouts.     

日本动画电影《龙猫》解读

宫崎骏动漫在日本动漫史上有举足轻重的地位。其中《龙猫》为其中一部描述淳朴乡村生活的电影。影片内容看似简单,但却包含有宫崎骏动漫的很多特色,如传统文化印记、儿童成长情结、飞行器情结以及旅行情结等。这些因素既成就了宫崎骏动漫的特点也影响着日本动漫的发展。     

Determinants of Internet Adoption in Beijing＇ s Residents --A HLM Analysis

使用2009年中国家庭动态跟踪调查的数据,利用分层线性模型分析社会人口因素和区域性因素对北京市居民网络使用因素的影响。研究发现,个人层面的年龄、性别、受教育程度、婚姻状态和家庭层面的家庭用电量、文化和教育支出、休闲娱乐支出、公交距离这些变量对个人网络使用有很大影响。此外,互联网使用对传统媒体中的电视、书刊的影响在统计上显著。     

高校教室开放方案的优化设计

利用数学建模设计高校自习教室的开放方案,采用教室、宿舍的位置分布与学生对教室的满意度以及节能环保等因素,建立多目标模型并求得最优结果。