基于地理信息可视化的空间认知研究     

杨静飞  张强 《测绘与空间地理信息》2013,36(7):12-14

地理信息可视化是在地理数据库驱动下,以地图形式表达地理信息的过程,它是可视化表达的重要组成部分。从空间认知的角度,深入研究地理信息可视化的过程;结合地理信息可视化的特点,提出了空间地理信息的表现形式以及空间认知的基本模式。  相似文献   

Modelling hourly evapotranspiration and soil water content at the grass-covered boundary-layer field site Falkenberg,Germany     

M. Wegehenkel  F. Beyrich 《水文科学杂志》2013,58(2):376-394

Abstract

The study analyses a 2-year period of hourly rates of real evapotranspiration (ETr) derived from eddy covariance measurements and soil water contents at depths from 8 to 90 cm, monitored by time domain reflectometry probes at the grass-covered boundary-layer field site Falkenberg of the Lindenberg Meteorological Observatory – Richard-Aßmann-Observatory, operated by the German Meteorological Service (DWD). The ETr rates and soil water contents were compared with the results of a modelling approach consisting of the Penman-Monteith equation and the soil water balance model Hydrus-1D using a noncompensatory and a compensatory root-water uptake model. After optimization of soil hydraulic parameters by inverse modelling, using measured soil water contents as the objective function, simulated and measured model outputs showed good agreement for soil water contents above 90 cm depth and for ETr rates simulated by our modelling approaches using noncompensatory root-water uptake. The application of a compensatory root-water uptake model led to a decrease in the simulation quality for the total investigation period.

Editor Z.W. Kundzewicz

Citation Wegehenkel, M. and Beyrich, F., 2014. Modelling of hourly evapotranspiration and soil water content at the grass-covered boundary-layer field site Falkenberg, Germany. Hydrological Sciences Journal, 59 (2), 376–394.  相似文献   

基于格式塔识别原则挖掘空间分布模式   总被引：9，自引：2，他引：9  

艾廷华  郭仁忠 《测绘学报》2007,36(3):302-308

面向空间群目标的分布模式识别是空间数据挖掘比较关注的问题。本研究基于空间认知原理与视觉识别格式塔完形原则并结合空间聚类方法对该问题进行研究,提出用于描述实体间差异的"视觉距离"概念,其定义综合考虑视觉识别中的位置、方向、大小差异,通过Delaunay三角网计算几何构造建立该距离计算的模型。在实验基础上提出基于最小支撑树MST的聚类方法,获得与视觉认知相一致的结果。研究试图表明一个观念,即通用性的数据处理模型在GIS实际应用时,需要根据GIS作为"空间认知"科学的原理,作技术方法上的改进,需要考虑认知主体在感知、辨析、识别、推理不同思维过程中的认知心理原则。  相似文献   

Editorial     

none 《The Cartographic journal》2013,50(1):3-4

Abstract

This paper describes the conservation of the first edition of the six-inches-to-one-mile Ordnance Survey maps of Ireland. It outlines the general problem of the acidity of paper on which nineteenth-century Ordnance Survey maps are printed and the peculiar problems of conserving a hand-coloured presentation set. Each stage in the process is described up to the final encapsulation of the maps in Melinex polyester film.  相似文献   

一种信息量和专家证据权重法耦合的成矿预测方法     

陈广洲  徐晓春  汪家权 《测绘科学》2013,38(1):146-149

本文选取安徽石台县丁香地区,以铜多金属矿为例,分析该区的地、物、化、遥数据,选择7个预测变量进行成矿定位预测研究。利用客观成矿预测法-信息量法进行计算,得到成矿预测变量所占的信息量,归一化得到变量的客观权重,依据专家知识,获得上述变量的主观权重,随后,采用D-S证据理论将上述主、客观权重进行融合得到综合权重,并采用该综合权重结合专家证据权重法获得单元格的后验概率,制作成矿有利度的分级色阶图。预测结果表明:该法能有效地综合来自主、客观方面的知识,预测结果更加科学、合理。与单纯的信息量法、专家证据权重法相比,取得了更好的成矿预测效果。  相似文献   

农村劳动力转移就业环境认知研究体系与方法   总被引：1，自引：0，他引：1  

赵春雨  苏勤  方觉曙 《地理研究》2013,32(5):891-901

根据行为地理学观点,通过农村劳动力转移就业决策过程分析,认为农村劳动力转移就业环境认知,是指农村劳动力面临多样化的就业地和就业环境,对其进行的环境外观感觉以及整体认识和综合解释过程。依据地理认知理论,构建了农村劳动力转移就业环境认知研究体系:基于目标与过程的转移就业环境认知研究;基于个体变量与群体文化因子的转移就业环境认知研究;转移就业环境认知层次(环境特征感知、环境对象认知、环境格局认知)研究。探讨了农村劳动力转移就业环境认知研究的基本方法:民族志方法、定量关系模型、时空路径等。可以预测,农村劳动力转移就业环境认知研究将促进混合研究路径的发展。  相似文献   

Extracting urban landmarks from geographical datasets using a random forests classifier     

Yue Lin  Yuyang Cai  Yue Gong  Lin Li 《International journal of geographical information science》2013,27(12):2406-2423

ABSTRACT

Urban landmarks are of significant importance to spatial cognition and route navigation. However, the current landmark extraction methods mainly focus on the visual salience of landmarks and are insufficient for obtaining high extraction accuracy when the size of the geographical dataset varies. This study introduces a random forests (RF) classifier combining with the synthetic minority oversampling technique (SMOTE) in urban landmark extraction. Both GIS and social sensing data are employed to quantify the structural and cognitive salience of the examined urban features, which are available from basic spatial databases or mainstream web service application programming interfaces (APIs). The results show that the SMOTE-RF model performs well in urban landmark extraction, with the values of recall, precision, F-measure and AUC reaching 0.851, 0.831, 0.841 and 0.841, respectively. Additionally, this method is suitable for both large and small geographical datasets. The ranking of variable importance given by this model further indicates that certain cognitive measures – such as feature class, Weibo popularity and Bing popularity – can serve as crucial factors for determining a landmark. The optimal variable combination for landmark extraction is also acquired, which might provide support for eliminating the variable selection requirement in other landmark extraction methods.  相似文献   

雅鲁藏布江表层沉积物地球化学元素研究   总被引：4，自引：0，他引：4  

陈鹏飞  李潮流  康世昌  张强弓  高少鹏 《地球化学》2012,(4):387-392

雅鲁藏布江流域还没有大的工业污染源,仍然属于自然河流.对雅鲁藏布江16个表层沉积样品的全样、小于20μm 和小于63μm 粒级的32种元素含量进行了测定,并分析了与人类活动密切相关的元素 Cr、Mn、Fe、Co、Ni、Cu、Zn、As、Cd 和 Pb 的含量分布特征,以及这些元素含量与粒径之间的关系.结果表明,多数元素(Cs 除外)与西藏土壤元素背景值相差不大, B、Cr、Ni、As 和 Cs 含量高于中国陆壳元素丰度值,但这些元素主要来源于该流域富含这些元素的页岩、片岩和千枚岩等母岩.由于相似的地球化学行为,沉积物中 Cr、Mn、Fe、Co、Ni、Cu、Zn 之间显著正相关;除 Pb、As 外,一些元素(如 Zn、Ni)与沉积物的粒径显著负相关  相似文献   

珠江三角洲环境梯度上葫芦藓中硫、氮含量 和δ13C、δ15N的差异及其环境指示     

吴清华  闵兴玲  周永章  卢强 《热带地理》2013,33(5):542-548

以华南地区广泛分布的葫芦藓为研究对象,以珠江三角洲环境梯度上的中心城区广州、近郊区肇庆及边缘区怀集3个地理单元作为样品采集地,对样本葫芦藓植物中的硫、氮元素含量和δ13C、δ15N的组成进行了研究。结果表明：葫芦藓植物中硫含量与工业化程度表现出正相关关系,其中硫含量广州、肇庆和怀集依次为2 485.86、1 778.15、1 339.84 mg/kg;葫芦藓氮含量与工业化程度表现出正相关关系,广州、肇庆和怀集依次为 2 106.50mg/kg、2 007.39mg/kg和1 661.88 mg/kg;葫芦藓的C/N值与交通量呈负相关关系,其中C/N值广州为18.377,肇庆18.513,怀集23.905,3地C/N值大小差异揭示了从广州到怀集的环境梯度上,大气氮的主要组份发生了变化,即广州大气中的氮元素来源以工业排放的NOx-N（硝态氮）为主,怀集大气中的氮元素来源以农业排放的NHx-N（铵态氮）为主。  相似文献   

Cognitive effects of long-term residence in the Antarctic environment     

YAN Gonggu  ;WU Songdi  ;WANG Tianle  ;ZHANG Xuemin  ;SAKLOFSKE Donald H 《极地研究(英文版)》2012,(3):170-175

This study examined whether prolonged residence in the Antarctica had a significant impact on cognitive performance. Participants were members of the 24th and 25th Chinese National Antarctic Research Expeditions. Cognitive performance was measured with tests designed to evaluate short-term recognition, memory search and spatial cognition, measured four times： January, March, April, and June 2010. Age was controlled as a covariate, and data were analyzed using repeated-measures ANOVA. The results revealed that subjects＇ short-term memory and recognition ability remained stable, while 82% of team members exhibited improved scores on a spatial cognitive ability test. These findings have important implications for furthering our understanding of cognitive functioning in extreme environments.  相似文献