基于可达性与场强模型的中国地级以上城市空间场能测度

空间场能是区域中心城市借助区域联系通道带动腹地发展而产生的"势能差"的抽象表达,可有效刻画区域发展格局与空间差异。采用主成分分析法与指标体系计算城市结节性指数,借助ArcGIS软件平台,采用累积耗费距离法、K阶数据场和ESDA等方法,综合测度了中国287个地级以上城市可达性与空间场能,并分别从省域、市域、县域等单元探讨了中国东中西三大地带与南北场能差异的空间格局与演变特征。结果表明:中国地级以上城市的可达性条件不断改善,平均可达性时间从1991年的246.98min缩短为2010年的193.43min。空间场能显著增长且空间分异性显著,分布结构由单核向多极网络状形态转变。县域场能存在显著的空间极化现象,场能热点区域的分布呈现显著的热点-次热点-次冷点-冷点自东向西带状分布的格局。依据场能分析结果,将全国划分为3个一级经济区和26个二级城市经济区。     

中国国民的健康指数及其区域差异

用“健康指数”来表征我国国民的健康状况,以预期寿命为核心,选择27项与寿命有密切关系的、能反映人的身体素质和化素质的健康指标,综合求得健康指数,基本上反映了各地区人群的健康状况及其区域差异,表明我国大城市和东南沿海地区人群的健康状况较好,西部地区稍差。     

Faunal exploitation and agricultural transitions in the South American agricultural limit

The southern Mendoza Province of Argentina constitutes the southernmost limit of Andean agriculture in South America. Archaeofaunal assemblages from sites in this region show a pattern of changing taxonomic diversity concomitant with the first appearance of domesticated plants. This pattern is characterised by an increase in prey diversity before the appearance of the first cultigens and a decrease in diversity after their arrival. Furthermore, the animal taxa exploited when domesticated plants entered the diet indicate a focus on big game. The pattern observed in southern Mendoza is in accord with ethnographic and archaeological models generated by faunal research worldwide. Copyright © 2008 John Wiley & Sons, Ltd.     

Experimental Study on Postponing the Deboning of FRP Sheets in Masonry Walls

ABSTRACT

A large number of buildings all around the world are constructed of unreinforced masonry. These structures do not act well during earthquakes because of their vulnerable behavior. In last two decades, fiber-reinforced polymers (FRPs) has been used widely in seismic rehabilitation and strengthening unreinforced concrete and masonry structures. One important issue in using FRP composites for strengthening masonry walls is the inopportune debonding of composites from the wall surface; thus, in this article new methods are proposed to further delay the mentioned debonding issue. For this purpose, 13 masonry panels with 100x870x870 mm dimension are strengthened by using carbon and glass FRPs (CFRPs and GFRPs). A variety of strengthening methods such as surface preparation, boring, grooving, nailing, and plaster are used to mount FRP composites to the walls. For each specimen subjected to diagonal compression test, the loading level along with tensile and compressive diagonal displacements are evaluated. In order to assess the effect of FRP composites, four unreinforced masonry walls are tested as well. The results show 110% increase in ductility index of reinforced specimens compared to the unreinforced ones.     

Indexing Immigration and Integration Policy: Lessons from Europe

Immigrant‐related policy indexes have become popular in both U.S. and European contexts, yet these projects boast distinct and divergent trajectories. European indices are characterized by rigorous conceptualization, specificity in elements of policy design (e.g., settings like fees or appeal process), and a variety of measurement strategies. By contrast, U.S. state‐level policy indices exhibit a lack of differentiation between immigration and integration policy and excessive generality in measurement and representation of policy instruments and settings, exacerbated in presenting a policy index as an aggregate count. This paper argues U.S. policy indexing can benefit from the European indexing experience. Following an overview of the state of each field, assessing concept differentiation, specification, and measurement in each, the paper illustrates how even the well‐conceived and specified European integration policy indices run into problems at the analysis stage. It presents a replication‐replacement study to illustrate divergent performance of highly correlated and conceptually agreeing indices, as well as methodological issues inherent to indices of low‐N, including using a policy index as a dependent variable and index selection absent a priori theorization. It concludes with suggestions for improving American immigration policy indices, as well as general observations on working with statistical power‐challenged indices and data limitations.     

Maternal work hours and adolescents’ body weight in South Korea

This study examined whether previous findings linking maternal work hours to obesity among children generalised to Asian populations. Using a nationally representative sample of Korean middle school students and their parents (N?=?1,873), ordinary least squares regression and logistic regression models assessed the association between maternal work hours and adolescents’ body mass index (BMI), overweight, and obesity. There were no significant associations between mothers’ weekly work hours and adolescents’ BMI (raw score, z-score, and percentile), overweight and obesity. These null associations were robust across different specifications for maternal employment, the proposed mediators, and outcome variables. Although longer maternal work hours were associated with adolescents’ longer unsupervised time, more sedentary behaviours (TV/Video/DVD viewing and electronic game playing), and less physical activity, this did not lead to an increase in the likelihood of being overweight and obese.     

高速公路网络化的时空收敛效应研究--以河南省为例

本文利用定量方法,以系统的观点,通过应用通达性系数、连接率等衡量网络连接度指标,以河南省为例,对高速公路网络化发展及由此引起的时空收敛性进行了评价.结果显示,高速公路的发展要历经树状网络、回路网络和格状网络三个阶段,最终走向网络的高级化,同时高速公路网络化使区域的空间通达性得到整体提高,河南省高速公路网络化的结果是在形成了不同时间的交通圈的基础上,逐步形成以郑州为核心的核心圈、外围圈和辐射圈三个高速公路经济圈,改变了区域空间经济结构.     

城市人居环境与满意度评价研究

从安全、舒适、和谐、方便等原则出发,选择建筑质量等5个准则,房型设计等56个因素作为调查与评价因子,建立城市人居环境满意度评估的基本框架,运用社会调查统计法对城区代表居住地域进行综合评价,指出南京市区人居环境总体处于发展阶段,并提出各居住地域人居环境优化措施和方案。     

中国人口文化素质指数及其空间分异

在构建人口文化素质指数的基础上,结合我国文化教育现状,对我国近十年的人口文化素质指数进行了定量与定性分析。结果表明:我国人口文化素质指数正在快速提高,但整体水平较低;人口文化素质指数的空间差异明显,东部最高,中部次之、西部最低,低于全国平均水平的省域主要位于西部;近2/3的省域发散趋异,收敛趋同的省域不到1/3,向上发散趋异的省域主要位于东、中部,向下发散趋异的省域主要位于西部,空间差异有扩大的趋势;人口文化素质指数与人口城市化水平、经济发展水平分别存在显著的线性关系和对数关系。     

黄土丘陵区纸坊沟流域生态恢复的经济特征分析

本文以黄土丘陵区纸坊沟流域为研究对象,从生态与经济协调发展的角度,分析了流域实施生态恢复试验示范建设以来经济特征的变化,评价其经济效应。结果表明:生态恢复使流域产业香农多样性指数大于1,显示产业结构得到优化;1998-2005年间综合生产力水平实现了由低到高的跨越,并且与产业香农多样性指数呈正相关;2005年恩格尔系数为0.45,基尼系数为0.22,Sen和FGT(α=2)贫困指数分别为0.2和0.17,表明生态恢复明显改善了当地农民的生活水平。