面向对象的泰安市高分辨率影像住宅建筑物提取     

董小姣  张东水  李朝奎 《地理空间信息》2013,11(1):67-69,13

基于eCognition Developer平台,以泰安市QuickBird影像为数据,采用面向对象多尺度分割、最邻近和隶属度分类,充分利用高分辨率QuickBird影像具有的丰富光谱、形状、纹理和结构等地物信息,对实验区进行分类并提取住宅建筑物信息。实验表明,与传统逐像元分类法相比,面向对象分类法有效地避免了分割区域的离散破碎,地类信息的提取更加完整、精确、高效。  相似文献   

Compact,concurrent, and contiguous: smart growth and 50 years of residential planning in the Toronto region     

Paul Mitchell Hess  André Sorensen 《Urban geography》2013,34(1):127-151

In this article, we use parcel-based land-use data to analyze 50 years of residential development in the Toronto region. We test two hypotheses: (1) Toronto’s form does not conform to conventional definitions of suburban sprawl and (2) Toronto’s suburban development shows high levels of continuity over time with relatively high densities and mixed housing types. Contrary to recent research suggesting a convergence of urban forms among North American metropolitan regions, Ontario’s robust planning system has created a distinctive, highly consistent pattern of residential development that has, for half a century, achieved many of the core goals of smart growth including relatively compact, contiguous, and concurrent development. This form continues to be automobile dependent, however, and is not producing many of the benefits ascribed to smart growth. Rather than continuing to adopt United States-inspired smart growth policies, a more ambitious set of initiatives will be required to address current regional challenges.  相似文献   

BEYOND POSTMODERNISM     

《Urban geography》2013,34(7):589-590

By simultaneously controlling for the spatial and social characteristics of neighborhoods, this study sheds new empirical light on the relationship between ethnic-enclave residence and ethnic-niche employment. Considering women's commuting constraints and their theoretically more local social networks, this study explores whether residential segregation may be a more important determinant of labor-market segregation for immigrant women than for men. The study finds that residential segregation plays an important role in sustaining labor-market segregation among immigrants, and that gender emerges as a salient mediating factor. While living in an ethnic enclave tends to be associated with ethnic-niche employment for both men and women, women who live in enclave neighborhoods have a higher rate of ethnic-niche employment than men. However, greater geographic accessibility to niche jobs is associated with niche employment for both immigrant men and women in general, and place-based context seems as important to men as women.  相似文献   

GEOSTATISTICS AS MEASURES OF SPATIAL SEGREGATION     

《Urban geography》2013,34(7):635-647

Traditional measures of segregation, such as the index of dissimilarity, have been criticized as aspatial in nature. Spatial measures of segregation have been proposed, but they are difficult to use. Based on the idea that segregation implies a spatial separation of ethnic groups, the degree of spatial correlation among groups can reflect the level of segregation. This paper suggests that several geostatistical measures, especially the standard deviational ellipse, are effective tools for capturing the spatial characteristics of a population group. By comparing the ellipses of different groups, measures of segregation can be derived. The paper demonstrates this approach to measuring segregation by way of both a simulation and a case study. [Key words: spatial segregation, geostatistics, deviational ellipses, spatial correspondence/correlation.]  相似文献   

THE REGIONAL GOVERNANCE CONTEXT IN RUSSIA: A GENERAL FRAMEWORK     

《Urban geography》2013,34(4):360-382

Many European urban regions have experienced a transformation from a compact monocentric toward a less compact polycentric urban region since the 1960s. The debate on emerging polycentricity in Europe so far tends to be more theoretical than analytical. The trend toward increasingly polycentric urban regions is meanwhile beyond dispute, but the effects of this transformation on urban regions and their components have only been explored to a limited extent. Are the "old" central cities only losing people, functions, and status to the new urban centers, or do these centers complement each other and specialize in terms of economic activities and population composition? This article presents evidence for the Amsterdam urban region regarding population distribution, selective migration, job growth, and economic specializations of the region's subcenters. It will become clear from our data that the Amsterdam urban region has indeed become more polycentric, but also that Amsterdam has managed to remain a vital center. The newer and older urban subcenters have become increasingly important, but rather than competing with Amsterdam, they develop in a complementary way.  相似文献   

Nature,Affordability, and Privacy as Motivations for Exurban Living     

《Urban geography》2013,34(7):705-723

Current demographic trends indicate that the 21st century will be one of exurban growth as more Americans seek out countryside home sites and their accompanying lifestyles. Two of the literature's conventional wisdoms regarding exurban migration motivations are critically examined in this study: (1) exurbanites are seeking home sites in close proximity to natural places, and (2) exurbanites are drawn to countryside areas because of the affordability of such locations. This study uses 34 snowball-sampled, semistructured interviews from Indiana and Illinois exurbanites to examine these two commonly held beliefs. Subjects reported that the natural environment did not primarily motivate their moves. Current home sites were, however, attractive due to their perceived affordability. The main, and remarkable, finding of this study is the strong desire for privacy that drew people to exurbia. The desire for privacy was cited as a main motivator by a large majority of the subjects interviewed.  相似文献   

Reconsidering Race,Class, and Residential Segregation in American Cities     

《Urban geography》2013,34(4):531-567

Scholars have often discounted social class as a substantial contributor to residential segregation by race, in part as a result of using the dissimilarity index, which is likely to show high levels of uneven group distribution regardless of socioeconomic status (SES), and in part as a result of using limited categories of SES. This study expands on prior research by examining residential segregation between black-alone and white-alone households in 36 metropolitan statistical areas (MSAs) with 2000 decennial census data, using both spatial unevenness (dissimilarity) and two types of experiential indicators (exposure indices), measuring SES across income levels and accounting for the presence of other races. Findings show that black households with higher incomes live in neighborhoods with greater exposure and lower isolation than do black households with lower incomes. Additionally, while the dissimilarity of black households decreases with income, unevenness is not as strongly connected to income as are the experiential measures. While race remains a primary determinant of residential segregation, results indicate substantial class differences.  相似文献   

湘南丘陵区农村居民点景观格局变化研究     

王彬武  周卫军  马苏  刘少坤 《地理空间信息》2011,(6):89-92

以湖南省郴州市北湖区为研究区,采用GIS技术、景观生态学原理和定量分析方法,研究了湘南丘陵区农村居民点用地总量、规模、空间形态、空间分布等景观格局变化特征,并对2004年和2009年2个时段不同海拔高度农村居民点景观格局动态变化进行了分析。结果表明:农村居民点在地形低缓处集聚;从2004年到2009年,北湖区农村居民点用地增加了168.7hm2;5年来丘陵区农村居民点平均规模增长了5.57%;在空间形态上,斑块分维数和形状指数2009年比2004年分别增加了0.031、0.189,农村居民点越来越破碎;在空间分布上,斑块间邻近距离不断缩短,平均最邻近距离缩短了13.29%,呈现出集中、连片分布的特点。  相似文献   

关于应用第二次土地调查成果联合开展农村宅基地权属调查及规范农民建房摸底调查的全新工作方法     

李洁园 《测绘与空间地理信息》2011,34(1):192-194,201

以广州增城市为例,介绍了应用第二次土地调查成果联合开展农村宅基地权属调查及规范农民建房摸底调查的一种全新工作方法,通过实践应用,得出联合调查这一新方法可以极大地加快工作进度,提高成果质量,节约政府财政成本,减少扰民.  相似文献   

基于耦合关系的干旱绿洲区农村居民点整理分区研究——以张掖市甘州区为例   总被引：1，自引：0，他引：1  

高小琛  石培基  潘竟虎  吕立刚 《地球科学进展》2011,26(10):1071-1078

以张掖市甘州区为例,利用系统科学理论与方法,研究农村居民点整理与农村社会经济之间的动态耦合规律,并以甘州区18个乡镇为研究单元,构建了农村居民点用地整理分区评价指标体系,利用熵值法确定权重,计算农村居民点整理的综合评价值,运用层次筛选法将研究区划分为5个整理区。研究结果：①甘州区农村居民点与农村社会经济的耦合度演化分为3个阶段：1995—1997年,二者不甚协调;1998—2003年,二者都处于持续、稳定、最佳协调发展状态;2004—2007年,二者处于相对稳定协调状态;目前二者处于不甚协调发展阶段。②农村居民点整理分区包括优先整理区、强化整理区、适度整理区、一般整理区和完善整理区。  相似文献