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741.
742.
This paper describes the creation of two new geographical boundary files, known respectively as lower zones and upper zones, for investigating social phenomena and visualising disparities in health outcomes in the Auckland Region of New Zealand. We test the effectiveness of contemporary automated zone design tools before applying an interactive approach which integrated computational power with expert local knowledge and visual interpretation to develop meaningful zones. We demonstrate that an interactive approach addresses multiple zone design criteria (e.g. respecting physical barriers, compactness and homogeneity) more effectively than is possible with an automated approach. 相似文献
743.
Monica Wachowicz Tianyu Liu 《International journal of geographical information science》2016,30(9):1806-1831
ABSTRACTCurrently the increase in the variety and volume of data sources is demanding new data analytical workflows for exploring them concurrently, especially if the goal is to detect spatial outliers. In this paper, we propose a data analytical workflow for exploring Call Detail Records in conjunction with geotagged tweets. The aim was to investigate how massive data point observations can be analyzed to detect spatial outliers in collective mobility patterns that are coupled with social ties. This workflow consists of analytical tasks that are developed based on the a-priori assumption of two isometric spaces where Natural Language Processing techniques are used to find spatial clusters from geotagged tweets in a Social Space which are later used to aggregate the Call Detail Records generated by antennas located in the Mobility Space. The dynamic weighted centroids that are given by the mean location of the number of calls per hour of all antennas that belong to a particular cluster are used to compute Standard Deviation Ellipses. The longer the period of time a weighted centroid stays outside of the 99.7% probability region of an ellipse, the highest the likelihood that they are spatial outliers. The workflow was implemented for the city of Dakar in Senegal. The results indicate that the further the hourly weighted centroids are skewed from the normal mean of an ellipse, the stronger the influence of a cluster is in finding spatial outliers. Furthermore, the longer the period of time the outliers stays outside of the 99.7% probability region of an ellipse, the highest the likelihood that the outliers are genuine and can be associated to extraordinary events such as natural disasters and national holidays. 相似文献
744.
江南水乡游客满意度的多维度影响因素测量模型 总被引:2,自引:1,他引:1
以江南水乡实证为例,从资源价值维度、旅游功能维度、心理满足维度、场所环境维度、负面评价维度等5个维度,探讨江南水乡游客满意度的多维度影响因素。偏最小二乘法回归显示,就江南水乡这种特定类型的旅游地而言,各个维度的影响重要性依次是:资源价值维度(0.203)>场所环境维度(0.183)>旅游功能维度(0.179)>心理满足维度(0.173)>负面评价维度(0.072)。重要的实践指示意义在于,对不同类型的旅游地应该进行针对性的游客满意度测评,包括其多维度的影响因素设计,及其影响因素可能存在的不同影响重要性的组合顺序。 相似文献
745.
The influence of eight factors on hydraulic parameters (transmissivity, hydraulic conductivity, specific capacity, specific
capacity index and maximum yields) are analysed, with data based on hydrogeological reports of 298 wells in dolomite aquifers
in Slovenia. Influence of lithological properties is very significant, with the highest values of analysed variables observed
in pure late-diagenetic intensely fractured Cordevolian dolomites, followed by Anisian and Late Triassic (‘Main’ dolomite)
dolomites with high carbonate content and high primary porosity. The hydraulic parameters are not dependent on aquifer age,
partial penetration, and well depth. The effects of depth to the water table and existence of low permeability overburden
are not of major importance. The hydraulic parameter values are higher the closer to a river the wells are located, and topographic
setting has a major effect. From the well reports, it was not always deduced whether the values of hydraulic conductivity
and transmissivity stand for the values of the fractures or of the matrix, so it is proposed that when there is doubt as to
whether these values are properly calculated, the most accurate parameters that can be used for a further prediction of aquifer
yield are the specific capacity and, to a somewhat lesser extent, the specific capacity index.
Résumé L’influence de 8 facteurs sur les paramètres hydrauliques (transmissivité, perméabilité, débit spécifique, courbe caractéristique et débit critique) est analysée sur des données issues des rapports de 298 puits dans les aquifères dolomitiques de Slovénie. L’influence des propriétés lithologiques est très significative : les valeurs les plus élevées sont observées dans les dolomies cordevoliennes pures, intensément fracturées et de diagénèse tardive, puis dans les dolomies de l’Anisien et du Trias Supérieur, avec une teneur élevée en carbonates et une forte porosité primaire. Les paramètres hydrauliques ne dépendent pas de l’age de l’aquifère, de la pénétration partielle ou de la profondeur. Les effets du niveau piézométrique et de l’existence d’une couverture peu perméable sont mineurs. Les paramètres hydrauliques augmentent à proximité des rivières, et la topographie a une influence majeure. Les rapports de forage ne stipulent pas systématiquement si les valeurs de perméabilité et de transmissivité sont relatives au réseau de fractures ou à la matrice ; il a par conséquent été proposé qu’en cas de doute sur le calcul de ces valeurs, les paramètres les plus significatifs pour remonter à la productivité de l’aquifère soient le débit spécifique et, dans une moindre mesure, la courbe caractéristique.
Resumen Se analiza la influencia de ocho factores sobre parámetros hidráulicos (transmisividad, conductividad hidráulica, capacidad específica, índice de capacidad específica, y rendimientos máximos) en base a datos de reportes hidrogeológicos de 298 pozos en acuíferos de dolomía en Eslovenia. La influencia de las propiedades litológicas es muy significativa con los valores más altos de variables analizadas presentes en dolomías Cordevolianas con diagénesis tardía fracturadas intensamente, seguidas por dolomías (dolomía “Principal”) del Anisiano y Triásico Tardío con alto contenido de carbonato y alta porosidad primaria. Los valores de los parámetros hidráulicos no son dependientes de la edad del acuífero, penetración parcial, y profundidad del pozo. Los efectos de profundidad al nivel freático y existencia de cobertura de baja permeabilidad no son de importancia fundamental. Los valores de los parámetros hidráulicos son más altos mientras más cerca de un río se localizan los pozos y el ámbito topográfico tiene un efecto principal. No se pudo deducir de los reportes de los pozos si los valores de transmisividad y conductividad hidráulica representan valores de las fracturas o de la matriz, de modo que se propone que cuando exista duda en cuanto a que si estos valores se han calculado de manera adecuada, los parámetros de mayor precisión que pueden utilizarse para una predicción futura del rendimiento del acuífero son la capacidad específica y, en menor medida, el índice de capacidad específica.相似文献
746.
An important issue of using the multiple-point (MP) statistical approach for reservoir modeling concerns the integration of
auxiliary constraints derived, for instance, from seismic information. There exist two methods in the literature for these
non-stationary MP simulations. One is based on an analytical approximation (the “τ-model”) of the conditional probabilities that involve auxiliary data. The degree of approximation with this method depends
on the parameter τ, whose inference is difficult in practice. The other method is based on the inference of these conditional probabilities
directly from training images. This method classifies the auxiliary data into a few classes. This classification is in general
arbitrary and therefore inconvenient in practice, especially in the case of continuous auxiliary constraints. In this paper,
we propose an alternative method for performing non-stationary MP simulations. This method accounts for the data support in
the modeling procedure and allows, in particular, continuous auxiliary data to be integrated into MP simulations. This method
avoids the major limitations of the previous methods, namely the use of an approximate analytical model and the reduction
of the auxiliary data into a limited number of classes. This method can be easily implemented in the existing MP simulation
codes. Numerical tests show good performance of this method both in reproducing the geometrical features of the training image
and in honouring the auxiliary data. 相似文献
747.
利用江苏和安徽2012—2014年151个国家站及2 600个区域站资料,对各类自动站资料的质量及其控制方法进行初步探讨。采用缺测资料统计、气候界限值检查、气候极值检查、内部一致性检查、二次迭代的空间一致性检查、时间一致性检查、持续性检查及综合决策算法分别对国家站和区域站资料进行系统的质量控制,并根据质量控制结果进行可疑站点的标记。结果显示:国家站各要素资料缺测率远低于区域站,且资料质量总体上均明显优于区域站;自动站各要素中温、压要素的质量最好,其次是相对湿度;除了空间一致性检查中风场资料的检查结果差别不大外,其余检查中区域站资料的未通过率均远高于国家站资料;将错误资料及可疑站点信息进行及时反馈,能改善实时资料质量,并为相应测站的检修与维护提供依据。 相似文献
748.
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
749.
从系统架构设计、功能设计、数据库设计、系统实现关键技术以及应用实例等方面对安徽省人事考试"赶考地图"系统的建设情况进行了详细阐述。该系统是以人事考试为主题而设计、开发的GIS系统,在将考区、考点,以及考生吃、住、行等专题信息空间化的基础上,使之具备了空间查询和分析的能力,在考试组织者与考生之间建立起一座桥梁,具有在同行业进行深入推广的应用前景。 相似文献
750.
This study describes and analyses an extraordinary array of pockmarks at the modern seabed of the Lower Congo Basin (offshore Angola), in order to understand the fluid migration routes and shallow plumbing system of the area. The 3D seismic visualization of feeding conduits (pipes) allowed the identification of the source interval for the fluids expelled during pockmark formation. Spatial statistics are used to show the relationship between the underlying (polarised) polygonal fault (PPFs) patterns and seabed pockmarks distributions. Our results show PPFs control the linear arrangement of pockmarks and feeder pipes along fault strike, but faults do not act as conduits. Spatial statistics also revealed pockmark occurrence is not considered to be random, especially at short distances to nearest neighbours (<200 m) where anti-clustering distributions suggest the presence of an exclusion zone around each pockmark in which no other pockmark will form. The results of this study are relevant for the understanding of shallow fluid plumbing systems in offshore settings, with implications on our current knowledge of overall fluid flow systems in hydrocarbon-rich continental margins. 相似文献