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101.
《Urban geography》2013,34(4):348-374
This research first develops a paradigm relating technology adoption, plant function, and location in different areas. It then examines empirically some of the paradigm's postulates dealing with occupation staffing patterns and wage rates in headquarters and production plants in different size cities and regions of the country using survey data. The research found that plants in large cities, headquarters plants, and plants in innovative regions paid higher wages than plants in small cities, production plants, and those in innovation-lagging regions. Headquarters plants and plants in large cities and innovative regions had a significantly larger number of scientists, engineers, and technicians on their staffs but few production workers. Production plants and those in small cities and towns and lagging regions had few professional workers but a significant number of production workers. For all types of plants an inverse relationship existed between plant size and city size. The postulated direct relationship between plant size and wage rates was not clearly evident in the survey data except for low skilled occupations. Neither was the relationship clearly evident in the U.S. Census data for the computer and semiconductor industries, as it was for total U.S. manufacturing.  相似文献   
102.
一种八邻域图像边界追踪改进算法   总被引:1,自引:0,他引:1  
针对传统的边界追踪算法主要用来提取环形封闭边界的局限性,提出了基于八邻域目标边界追踪改进算法,着重解决了图像追踪过程中边界重叠部位的内外边界标定与"孤岛"处理。应用本文算法与摩尔邻域边界追踪算法分别对MPEG7-CE图形库中的4幅图像进行边界提取测试,结果表明改进算法提取结果正确。最后将本文算法应用于北极冰雪图像海冰边界提取,试验结果表明改进的算法可以有效提取大范围具有复杂拓扑关系的图像边界。  相似文献   
103.
学校分区问题混合元启发算法研究   总被引:5,自引:0,他引:5  
中国城市义务教育学校采用单校划片或多校划片的方式确定招生范围,落实就近入学的法律要求。针对多校划片这一新的学校分区问题,提出“先学校分组,再学生分派”的策略进行划片,并设计了学校分组线性规划模型和学校分区混合元启发算法。分区算法包括初始解构造、邻域搜索算子、破坏重建扰动、集合划分问题(SPP)建模与求解等基本模块,在多启动迭代局部搜索(ILS)算法框架中进行问题求解。通过多启动、随机搜索、破坏重建扰动等机制提升算法的多样性,并引入SPP模型提升算法的全局寻优能力。选择一个县级市和一个市辖区分别进行学校划片实验,结果表明:混合元启发算法优化性能优异且收敛性好,适用于求解单校划片和多校划片问题;SPP模型在单校划片问题中具有明显的优势。  相似文献   
104.
Basic concepts of cultural historical geography have been applied to a variety of community issues in St. Paul, MN. Through the process a sense of place has been developed at several scales. This inclusive sense of place has provided a link among various factions and made possible several compromises in land use and economic development issues. Most of the work was done through undergraduate field seminars.  相似文献   
105.
GIS栅格数据能表述连续变化的空间现象,它每个像元的属性值有连续数据和离散数据2种。针对栅格连续数值空间进行分析,突破传统的基于栅格本身邻域位置的研究方法,从属性值本身来定义邻域,基于属性距离度量公式来定义数据的领域。不同的邻域大小,一个栅格像元可以得到不同的邻域;并且从粗糙逼近的角度来探讨邻域信息粒子样本的上、下近似...  相似文献   
106.
线与面目标间拓扑关系的层次表达方法   总被引:2,自引:1,他引:2  
邓敏  马杭英 《测绘学报》2008,37(4):0-520
拓扑关系已广泛应用于空间查询、相似性分析、制图综合、不一致性探测以及空间推理等实际应用中。本文研究IR2中一条线与一个简单面目标拓扑关系的描述和区分方法,采用的基本策略是分解与组合方法。首先,将线/面拓扑关系分为两类:基本关系和复合关系。其中复合关系描述为若干个基本关系的组合,即基本关系的一个集合。然后,提出了基本拓扑关系分类和区分方法,建立了相应的层次概念邻域图。针对复合拓扑关系,从空间集合的角度提出了具有三个层次的拓扑不变量,分别是(a)集合层次上的分离数和维数,(b)元素层次上的交分量类型和(c)综合层次上的交分量序列。分析发现,在IR2中一条线与一个简单面目标间具有16种潜在的基本关系。其中,它们的13种是描述复合线/面关系的基本构成单元。  相似文献   
107.
曹晨  甄峰  姜玉培 《地理研究》2021,40(10):2823-2837
通勤是大部分城市就业者日常工作所必须面对的问题。相比宏观层面的城市建成环境,微观层面的邻里环境感知及个体健康与通勤模式选择的联系更为密切。以南京市主城区8个社区为案例地,利用结构方程模型探究邻里环境感知与个体健康对城市就业者通勤模式选择的影响。首先借助问卷调查数据,将通勤模式分为积极通勤、公共交通通勤、电动车/摩托车通勤以及小汽车通勤四类;其次使用因子分析法确定邻里环境感知的潜变量,并将个体健康分为身体健康、心理健康与健康行为3个潜变量;最后构建结构方程模型的理论框架并进行实证分析。研究发现:① 邻里环境感知变量中服务设施感知、环境品质感知对通勤模式选择存在显著的直接效应,交通安全感知对通勤模式选择存在显著的间接效应。② 个体健康变量中,心理健康与健康行为对通勤模式选择存在显著的直接效应。③ 通勤距离与社会经济属性对通勤模式选择存在显著的直接效应,同时社会经济属性对通勤模式选择亦存在显著的间接效应。基于研究结果,提出有效提升就业者对于社区环境的主观感受,进而提高就业者参与健康行为的意愿与就业者的健康水平,从而引导其选择更加健康和绿色的通勤模式。  相似文献   
108.
This article develops an innovative and flexible Bayesian spatial multilevel model to examine the sociospatial variations in perceived neighborhood satisfaction, using a large-scale household satisfaction survey in Beijing. In particular, we investigate the impact of a variety of housing tenure types on neighborhood satisfaction, controlling for household and individual sociodemographic attributes and geographical contextual effects. The proposed methodology offers a flexible framework for modeling spatially clustered survey data widely used in social science research by explicitly accounting for spatial dependence and heterogeneity effects. The results show that neighborhood satisfaction is influenced by individual, locational, and contextual factors. Homeowners, except those of resettlement housing, tend to be more satisfied with their neighborhood environment than renters. Moreover, the impacts of housing tenure types on satisfaction vary significantly in different neighborhood contexts and spatial locations.  相似文献   
109.
《Urban geography》2013,34(3):212-231
Annual price indices of owner-occupied single-family houses are estimated for 111 neighborhoods in Milwaukee, Wisconsin, for the period of 1971-1993 using hedonic price methods controlling for quality differences across housing units. The rates of price appreciation vary significantly from neighborhood to neighborhood. During the 22-year study period, nominal house prices in some neighborhoods increased more than 500%, whereas those in others decreased. In general, the neighborhoods close to each other exhibit similar price movements. In some cases, however, there are sharp differences between the neighborhoods when strong boundaries, such as a river or an expressway, exist between them even though the physical distance between them is small. Poor neighborhoods generally have experienced low appreciation rates, although the racial composition and the crime rate in the neighborhood seem to contribute the differential as well.  相似文献   
110.
《Urban geography》2013,34(3):261-270
In addition to his famous concentric-zone model of urban form, Ernest W. Burgess in 1929 outlined an altitudinal-zone model. It proposed a positive relationship in “hills cities” between the socioeconomic status of residents and the elevations at which they live. This article suggests a theoretical rationale for this “other Burgess model” based on the role of amenities in contemporary residential choice. Its performance compares favorably to that of competing models in an empirical test in cities selected to approximate as closely as possible the conditions that it assumes. [Key words: amenities, E. W. Burgess, urban form.]  相似文献   
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