Reading and listening progress in segregated primary schools: Does ethnic and socioeconomic classroom composition matter?

This study aimed to investigate the relationship of classroom composition factors with reading and listening comprehension achievement and progress in socially and ethnically segregated primary schools in Flanders (Belgium). Specifically, using a three‐level multivariate repeated measures analysis, it examined the association of reading and listening achievement and progress with ethnic diversity, the proportion of non‐native students and the average socioeconomic status of the class, taking into account student characteristics. At the beginning and end of the school year, reading tests, listening tests and questionnaires were administered to a sample of 7‐ and 8‐year‐old students (n = 683) in 42 second‐grade classes. Students' listening comprehension achievement at the beginning of the school year was negatively related to having a home language other than the language of instruction and to classes with a high proportion of non‐native students. However, progress in listening comprehension was not significantly associated with any student or classroom composition factors. Students whose mothers had a lower level of education performed lower on reading comprehension at the beginning of the school year, while at the end of the school year students whose mothers had a higher level of education were at a greater disadvantage. Limitations of this study and directions for future research are discussed.     

昆明市旅游资源空间结构分析

旅游资源是旅游区域空间竞争的基础,其空间分布及结构影响旅游区域的空间竞争。运用最近邻指数R、β指数、γ指数、平均径路长、紧密度指数5种分析技术,对昆明市旅游资源的空间分布形态以及空间网络结构的连接性、通达性等进行了全面的分析,认为加强和加快构建昆明旅游区旅游交通网络,提高旅游交通网络结构的连接性、通达性水平,是昆明旅游区面临的一个重要问题。     

城市规划中的美学原理研究

城市美具有自身的内在特征，必须体现形式美的多样统一规律，又与技术、功能、环境以及美的秩序差异具有内在关系。创造美的空间环境，必须遵循美的内在本质特征。     

GIS支持下土地利用空间演变过程的马尔可夫模拟研究--以上海市中心城区为例

以上海市中心城市区近50年来有代表性的土地利用类型图为数据源，采用GIS技术分析了上海市近50年来的土地利用总量变化；并在GIS支持下分别计算出相邻时间点不同土地利用类型的状态转移矩阵，利用马尔可夫模型对上海市中心城区土地利用空间演变过程进行了模拟分析和定量预测研究。     

A different type of charter school: in prestige charters,a rise in cachet equals a decline in access

This paper seeks to elucidate a specific type of charter school. While much has been written about school choice and the expanding charter school segment, a growing and important number of charter schools do not fit in to the common understanding of these schools. Distinct from many of their counterparts, prestige charter schools have the following two features: elements which foster a reputation similar to that of elite private schools and a student population demographically distinct from local public district schools – whereby the prestige charters serve a disproportionate number of advantaged families. The prestige elements include: founding by advantaged community members; parental involvement; wait lists; popularity with advantaged professionals; high test scores; and niche themes. The authors will show through two in-depth case studies that prestige charter schools work hand-in-hand with gentrification in urban neighborhoods, and result in racial and class segregation and inequality. This paper examines how these charter schools struggle when a rise in prestige coincides with a decline in access for low-income students. The authors recommend that given the current system of school choice, prestige charter schools must use tools and mechanisms to maintain demographic diversity and educational equity which is in the best interest of all children.     

半导体锗纳米团簇和纳米层的生成结构与PL谱研究

在硅锗合金衬底上采用氧化等制膜方式生成零维和二维的纳米结构样品，用高精度椭偏仪(HPE)、卢瑟福背散射谱仪(RBS)和高分辩率扫描透射电子显微镜(HR—STEM)测量样品的纳米结构．并采用美国威思康新州立大学开发的Rump模拟软件进行精细结构模拟．并测量出样品横断面锗纳米团簇和纳米层的PL谱。在硅锗合金的氧化层表面中首次发现纳米锗量子点组成的几个纳米厚的盖帽膜结构．首次提出的生成硅锗纳米结构的优化加工条件的氧化时问和氧化温度匹配公式的理论模型与实验结果拟合得很好．     

中小城市交通秩序混乱的空间特征及其影响路径分析——基于空间生产的视角

交通秩序混乱是造成交通拥堵的主要原因之一。文章以空间生产理论三重空间逻辑为框架,以河南省信阳市为案例,致力于揭示中小城市交通秩序混乱的空间特征。研究发现:道路侵占和无序行驶是交通秩序混乱的主要空间特征,基于不同交通主体和道路空间类型,可概括为三类道路侵占和二类无序行驶模式。道路侵占是无序行驶的直接原因,且表现为在道路横断面视角下自外向内的空间作用路径。导致中小城市交通秩序混乱的根本原因是交通产品提供者和管理者构想的交通空间秩序和交通产品使用主体空间感知和行动的对立;直接原因是交通影响者违规挤占交通空间、非机动车驾驶者及行人交通意识淡薄和交通执法人员执法不严或无法可依。     

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.     

基于核心素养的高中地理教学刍探

高中地理的课堂教学要围绕核心素养的培养,从人地协调观、综合思维、区域认知和地理实践力方面积极创新教学途径。教师应当通过多种多样的课堂形式,全面提升学生解读地图的能力,运用生活化的课堂教学培养学生的地理探索能力,结合多媒体教学培养学生地理空间思维,注重问题引导以培养学生综合思维。     

基于GIS空间数据的地图印前技术探讨

地图印前技术是GIS桌面制图与印前系统紧密结合并共同前行的一项技术。本文从分析GIS空间数据的特征及其应用于地图印前的欠缺之处出发，探讨了基于GIS空间数据的地图印前技术中图层的组织、符号库的管理、字库的选择、地图标注的应用等关键问题，