三角形packing问题中零自由度动作的分类

三角形packing问题中三角形可以进行连续平移和旋转,如果不对三角形放置动作进行限制,则计算将无法实现。本文提出了零自由度动作概念,并对它进行了详细的分类,为求解三角形Packing问题建立了一个接近客观情况的模型。     

构建我国高校教师良性流动机制

随着市场经济体制的不断完善和教师主体意识的增强，高校问教师流动速度大大加快，导致教师资源分布的不合理，教师过剩与短缺、开发与浪费并存的现象普遍存在，教师资源总体配置效益不高。构建我国高校教师良性流动机制要坚持教师与高校共同效益最大化的原则，处理好“流”与“留”的关系。高校教师良性流动机制主要包括“来去自由”、“信息化”、“柔性化”、”三个留人”等流动机制。     

《切韵》系韵书歌戈韵分合性质研究--歌戈韵在韵书中的反切比较

我们用几种韵书比较切下字系统 ,发现有许多字原本属于开口韵歌、哿的字在《集韵》里分别收在合口韵戈、果韵中 ,但切下字却仍用开口字。开合混置的韵字特别多 ,不仅有开口韵放入合口韵 ,而且也有合口韵放入开口韵 ,但切下字系统不变     

旅游者人数变动的统计预测分析

旅游业是一个波动性较强的产业，由于受旅游市场多种因素的影响，往往导致旅游目的地和旅游景点旅游人数经常发生变动，因此对旅游人数进行统计、分析和预测有助于调节旅游市场的供求平衡，合理安排和开发旅游景点，做好旅游接待工作。本通过使用一些统计预测模型及相应的预测方法，对旅游的人数变动、流向变动和季节变动进行了一定的统计、分析和预测，对旅游业实践具有一定的指导意义。     

单层单极聚合物发光器件中的输运性质

假设载流子浓度按指数关系变化,认为注入电流为热电子电流和隧穿电流,通过引入电荷空间分布特征长度和有效迁移率,讨论了单层单极聚合物发光器件内部的输运性质.结果表明:(1)电荷空间分布特征长度对器件中的电场强度,电流有很大影响;(2)载流子迁移率在注入电极附近减小,而在另一电极附近增加.本文对这些现象给予了解释.     

Fees,flows and imaginaries: exploring the destination choices arising from intra-national student mobility

ABSTRACT

Are intra-national student flows driven by the same forces as international student mobility? This paper addresses this question by analysing cross-border student mobility in the UK. The paper identifies four principles that one might expect to drive the destination choices of students from Scotland enrolling in English universities. Following a statistical analysis of student destination choices, it is argued that cross-border moves from Scotland to England are stimulated by some of the same global forces as international student mobility (such as a desire to accumulate cultural capital), but in terms of destination choice the imaginaries held by Scottish students of ‘good’ places to study in England to accumulate cultural capital are constructed differently from the imaginaries of international students.     

美国吸引高质量教师到薄弱学校的新举措

20世纪90年代以来,美国教师需求存在很大缺口,而薄弱学校由于新教师多、缺乏支持性管理、教师待遇不高导致教师流失率居高不下。在此背景下,美国对薄弱学校教师质量要求却比以前更高了。为了吸引高质量教师到薄弱学校,美国一方面设置专项资金用于吸引和稳定高质量教师,制定政策对学校高质量教师提出硬性要求或通过间接的政策调控迫使薄弱学校吸引和稳定高质量教师;另一方面改善薄弱学校管理,加强对新教师的入职指导和要求,提供支持性管理,给教师以更多的自主权,提供事业发展的机会和前景。     

某型空地导弹机动性分析

针对某型空地导弹机动性分析时气动参数的非线性特性,提出采用逐步逼近最终达到力矩平衡求解最大平衡攻角及可用法向过载的方法,解决了具有非线性气动特性导弹的可用法向过载计算问题,通过弹道仿真,对需用法向过载和可用法向过载进行了计算和对比．计算结果表明该导弹具有足够的机动能力,为总体设计和控制系统设计提供了依据．     

博洛尼亚进程促进大学生流动的政策发展及经费支持措施

博洛尼亚进程被视为一系列欧洲会议以及一些旨在2010年前建立欧洲高教区的政策决定的产物和延续。在促进高校学生流动上,博洛尼亚进程是以教育质量为根本,结合学位制度、质量保障体系、学分转换系统、信贷系统等辅助措施,力图打破阻碍教育因素流动的障碍。从发展进程上看,其是以欧洲政治、经济一体化的深入为前提,追求欧洲高等教育在全球范围内的重新崛起。从挪威、瑞士、奥地利等代表性国家为促进高校学生流动采取的经费支持措施看,虽然有相关贷款制度、奖学金制度、经费补助政策的支持,但在国际金融危机的阴影下,各国财政支持的力度并不能很好地支撑博洛尼亚进程相关目标的实现。     

Child welfare characteristics in a sample of youth involved in commercial sex: An exploratory study

BackgroundHomeless, runaway, and youth exiting foster care are vulnerable to sexual exploitation, but little research has parsed the societal, community, and individual factors that contribute to their risk.Objectives(1) To estimate child welfare characteristics in a sample of homeless young people who engaged in commercial sex (CS); and (2) To compare young people who were sex trafficked (ST) to those who engaged in some other form of CS.Participants and settingThis study includes 98 homeless young people in Philadelphia, PA, Phoenix, AZ, and Washington, DC, who were interviewed for a larger study of ST and endorsed engagement in CS.MethodsWe used a non-probability, purposive, maximum variation sampling procedure. Interviews were recorded and responses were simultaneously noted on a standardized interview form. Data were analyzed through means, frequencies, and bivariate tests of association.ResultsAverage age of the full sample of 98 homeless young people was 20.9 years; 48% were female and 50% were Black/African American. Forty-six percent of the full sample was sex trafficked. The full sample and the victims of ST differed significantly in three child welfare characteristics, with the ST group more likely to have been maltreated as children, more likely to have had family involvement with the child welfare system (CWS), and more likely to report higher rates of living someplace other than with their biological parents as children.ConclusionsST victims differ from those who engaged in other forms of CS in histories of maltreatment, involvement with the CWS, and exposure to residential instability while growing up.