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21.
基于GIS的西安市城市扩展与模拟研究   总被引:4,自引:0,他引:4  
本文以西安市为研究区域,以2002年ETM影像和2007年TM影像遥感数据为城市扩展动态变化的主要信息来源,采用逻辑回归模型并结合GIS技术对西安市的城市空间扩展进行模拟。研究选取了道路、河流、地裂缝、地面沉降、人口和GDP等6个因子,建立了西安市城市扩展的逻辑回归模型,并根据所建立的模型对西安市的城市扩展进行了模拟,结果表明,所建立的逻辑回归模型能够较好地模拟西安市的城市扩展,对西安市城市扩展的驱动力具有较强的解释作用,其中对城市扩展影响最重要的因素为距道路距离。  相似文献   
22.
This study evaluates a method for obtaining stature estimates for populations represented by skeletal material, with individuals buried in a supine position. During the excavation of a Danish mediaeval cemetery, in situ skeletal length in the grave was measured from a point above the cranial point farthest from the body to the most distal point of the talus. The measurement was made with a folding rule placed on the sagittal midline of the skeleton, allowed to follow any curvature of the skeleton in situ. In the laboratory, stature was reconstructed anatomically, and this stature was regarded as an accurate estimate of living stature. Stature was also reconstructed from femur length by two linear regression procedures: 1) by sample and sex specific formulae, employing a leave‐one‐out approach, and 2) by sex wise formulae for Euro‐Americans from Trotter & Gleser (1952, American Journal of Physical Anthropology 10 : 463–514). Skeletal length in the grave and the two stature estimates based on linear regression were compared to anatomically reconstructed stature. Skeletal length in the grave estimated anatomically reconstructed stature with practically no bias (95% CI: −1.3–1.5 cm). Sample specific regression formulae estimated anatomically reconstructed stature also with no bias (95% CI: −1.2–1.1 cm). In contrast, statures calculated from Trotter & Gleser's regression formulae estimated anatomically reconstructed stature with a bias of about 4 cm (95% CI: 3.3–5.0 cm). Estimates of stature variance were biased for all three estimation procedures. However, for samples of adults, an adjusted variance estimate can be obtained by subtracting 8.7 cm2 from the variance obtained from skeletal lengths in the grave. It is recommended to measure skeletal length in the grave whenever possible, and use this measurement for estimating statures for prehistoric and early historic populations. Copyright © 2005 John Wiley & Sons, Ltd.  相似文献   
23.
基于SEA的AGA-SVR节假日客流量预测方法研究   总被引:2,自引:0,他引:2  
节假日旅游客流量由于游客在短期内大量集中于同一地点、不同节假日休假时间长短、所处季节等不同,呈现复杂非线性特征和明显季节性特点.本文提出一种基于季节指数调整(Seasonal Exponential Adjustment,SEA)的自适应遗传算法(Adaptive Genetic Algorithm,AGA)-支持向量回归 (Support Vector Regression,SVR)预测模型,即基于SEA的AGA-SVR模型,并用国内著名5A级风景区黄山2008~2012年节假日客流量数据对模型进行验证.研究结果表明,基于SEA的AGA-SVR预测模型能够准确处理节假日旅游客流量预测中的非线性和季节性问题,较AGA-SVR和GA-SVR等方法具有更高的预测精度,在旅游预测领域应用前景广阔.  相似文献   
24.
以2014-2016年长三角135个区县的房价为基本数据,通过数据的空间提取、分异指数测算、热点分析等方法,对长三角县域的房价空间分异格局进行了研究。结果表明:长三角房价空间分异格局与其城市体系结构基本一致,呈现出多极核分布特征;长三角整体的房价空间分异的不平衡性正在加剧;冷热点的空间分布格局相对稳定,热点的数量波动下降,冷点的数量波动上升。在此基础上,遴选出经济资源、人力资源、社会资源和行政资源要素类型,利用多元线性回归模型分析了长三角房价空间分异的影响因素。  相似文献   
25.
This article maps and discusses the legal processing of rape cases in Norwegian appellate courts. Drawing on data from a multivariate regression analysis and a qualitative frame analysis, we examine the significance of space, accuser-convict prior relationship, the social context, accuser-convict marital relationship status, and convict racial background for grading of sentences in rape cases. The data-set consists of 176 rape cases that were processed in 2011 and 2012. Excluding acquittals and controlling for the application of relevant legal provisions, we find that sentences are reduced by 30% if the rape occurs in a private space as opposed to a public space. If the rape occurs at a party or is committed by a perpetrator who is a member of a racial majority, we find that sentences are reduced by 20%. A prior relationship between the victim and the perpetrator reduces sentencing by 18%. Results regarding victims of marital rape are inconclusive. The study concludes that sentencing is stratified according to the public/private divide, prior relationship, social context and race. Despite progress made on behalf of victims of domestic violence and a gradual implementation of stricter sentencing in line with legislative intentions, the legal processing of rape cases is permeated by race and gender discrimination.  相似文献   
26.
In delivering public policy, governments worldwide increasingly partner with diverse sets of stakeholders. This spreads commercial risk, but particularly where agendas diverge, introduces new risks related to trust in relationships. The “risk hypothesis” distinguishes between networks for “cooperation” problems, where partners have high individual payoffs for uncooperative behaviors, and “coordination” problems, where partners subscribe to a common goal and uncooperative behaviors are less rewarding. We used mixed‐methods to study networks of local and state government, developers, and consultants that center on joint‐venture partnerships for developing new urban, residential projects. Statistical network methods showed that within the mix of partners involved in development projects, only state governments displayed structural patterns associated with solving “cooperation” problems (rather than coordination). In other words, the patterns of state government interactions showed they are most exposed to risky relationships. In contrast to the state governments’ apparent exposure to risk, qualitative data showed they are not only well trusted but also overall the partnership networks reported very low levels of conflict. By exploring the distribution of “cooperation” and “coordination,” we identified which stakeholders perceived most risk. In our case, how the state governments’ structure interactions in response to risky relationships leads to an overall network characterized by trust.  相似文献   
27.
While the land use-street network nexus is well acknowledged, evidence for the one-way impacts of land-use patterns on street accessibility is still inadequate. The measurements of land-use patterns and street accessibility lack systematic knowledge. Their empirical correlations also lack geographical variability, constraining site-specific land-use practices. Therefore, this study overcame the aforementioned limitations by examining the two-level spatial models to formulate accessibility-oriented land plans, using a well-developed Chinese city as an example. Firstly, two landscape metrics—Euclidean Nearest-Neighbor Distance (ENN) and Similarity Index (SIMI)—were used to quantify the intra- and inter-land-use configurations, respectively. Both city-level and local accessibility were measured using spatial design network analysis. Performing both ordinary least squares (OLS) and geographically weighted regression (GWR) models, results identified the statistically significant effects of inter-land-use patterns on two-level street accessibility. An exception was that land-use configurations within residential and industrial regions were irrelevant to street accessibility. We also found GWR was a better-fitting model than OLS when estimating locally-varied accessibility, suggesting hierarchical multiscale land-use planning. Overall, locally heterogeneous evidence in this study can substantialize land use-street network interactions and support the decision-making and implementation of place-specific accessibility-oriented land use.  相似文献   
28.
Remains of anadromous Pacific salmon and trout (genus Oncorhynchus) are common in archaeological sites from California to Alaska; however, morphological similarity generally precludes species identification, limiting the range of questions that salmonid remains can address in relation to past human use and ongoing efforts in conservation biology. We developed a relatively simple, rapid, and non-destructive way to classify salmon and trout vertebrae from archaeological contexts to species using length, height and the ratio of length to height. Modern reference material was obtained from all seven anadromous Oncorhynchus species native to the west coast of North America. A minimum of ten adult Chinook (Oncorhynchus tshawytscha), chum (Oncorhynchus keta), coho (Oncorhynchus kisutch), pink (Oncorhynchus gorbuscha), and sockeye salmon (Oncorhynchus nerka) and cutthroat (Oncorhynchus clarki clarki) and steelhead trout (Oncorhynchus mykiss) were skeletonized and vertebra length and height were measured. Morphometric analyses compared species classification success based on Linear Discriminant Analysis (LDA), Classification and Regression Trees (CART), and randomForest, with CART performing the best. Classification analyses used all seven species individually, but because of considerable overlap among several species we also conducted analyses on four species groupings. We assigned Chinook salmon and cutthroat to their own groups based on their dissimilarities from each other and the other species. The remaining species were divided into two group complexes (a) chum, coho, and steelhead; and (b) pink and sockeye. When we grouped species according to similar morphology, CART overall success rates increased, ranging from 92 to 100%. Individual species with the highest successful classification rates using CART were Chinook salmon and cutthroat, from 92 to 100%, respectively. We applied our classification to an assemblage of ancient (1000–3000 year old) salmonid vertebrae from the Swiftwater Rockshelters excavations on the upper Wenatchee River in Washington State, U.S.A.  相似文献   
29.
We investigate the spatial extent of agglomeration economies across the wage earnings distribution using economic mass (total employment) in four distance bands around each individual’s establishment in a quantile regression framework. We control for observable and unobservable individual and establishment characteristics. Remaining endogeneity in the model is assessed with a set of instrumental variables. Results indicate a positive effect of economic mass on wage earnings up to 25 km away from the establishment. The spatial extent of agglomeration economies is similar across the wage earnings distribution. However, increases in economic mass shift the wage earnings distribution in a nonsymmetric way.  相似文献   
30.
The recent financial and economic crisis had substantial but spatially differentiated impacts on growth. However, there is still a lot left to be understood about the local aspects of the crisis. One of these aspects is its socio-economic consequences. This paper investigates local socio-economic change to Danish towns from 2008 to 2013, with a focus on the impact of local labour market (LLM) structures on change. Socio-economic change in towns is measured both directly as mean income and employment growth, and indirectly as population and human capital growth. The paper relies on micro-data and uses robust regression to generate results. Several findings are presented, but the two main conclusions are: first, the LLM structures of towns still influence local socio-economic development; and, second, towns experience better socio-economic development if they are in close proximity to a larger labour market and/or have a large ratio of commuters in the working population.  相似文献   
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