危岩崩塌运动分析及Rockfall数值模拟分析比较研究

边坡危岩崩塌是一种危害性极大的地质灾害,本文通过落石的运动轨迹,根据牛顿运动定律和能量守恒定律,分析总结了落石的运动速度及落石的撞击能量,最后再利用rockfall软件进行计算比较,为边坡防护提供科学合理的防护形式。     

Generalized thin sheet analysis in magnetotellurics: an extension of Price's analysis

Summary. Price's thin sheet analysis for electromagnetic fields has been extended in order to model the effects of crustal resistivity and conductivity variations on magnetotelluric fields. These extensions allow for a general layered medium below the crust and also account for the vertical resistance of the crust as well as its horizontal conductance. An important parameter emerges from the analysis which determines the distance it takes for the crustal current levels to readjust to changes in the crustal conductance. This adjustment distance is given by the square root of the conductivity thickness product multiplied by the resistivity thickness product. Approximate analytical solutions were developed for two-dimensional geometries in order to demonstrate these effects as well as the modifications produced by finite source wavelengths.     

Two-tier analysis in palaeomagnetism

Summary. The statistical analysis necessary for isolating the between-site dispersion in palaeomagnetic studies is presented, both for the case of a common within-site precision and for variable within-site precision.
Approximate distributions are derived for all the relavant statistics. It is shown that if it is necessary to perform a two-tier analysis the overall true mean direction should be estimated as the mean of individual site mean directions and an equation for the semi-angle of the cone of confidence about this mean direction is derived.
The last section of the paper lays out the process by which a two-tier analysis should be performed together with relevant equations.     

Attribute trajectory analysis: a framework to analyse attribute changes using trajectory analysis techniques

Trajectory analysis has attracted growing attention in the research field of geography. Beyond traditional moving object trajectories, another type of trajectory exists in which the coordinates are object attributes rather than geographical coordinates. In this paper, a framework to analyse these so-called attribute trajectories is proposed that uses four techniques typically employed in the analysis of moving object trajectories: the Reeb graph, the similarity matrix, the convoy and the mega-convoy. The Reeb graph provides the ability to visualise the temporal dynamics of attribute similarities. The similarity matrix is a supplement of the Reeb graph whose purpose is to visualise the pairwise similarities among the attributes. Moreover, the similarity matrix forms a basis for clustering. The convoy highlights objects whose attributes remain similar for a sufficiently long period. The mega-convoy reduces the number of convoys and reveals their evolutionary histories by merging overlapping convoys. A small real-world meteorological dataset is used as an example to illustrate the attribute trajectory analysis framework and the techniques. This paper aims to form a starting point for applying trajectory analysis techniques in many research fields.     

Geographically weighted principal components analysis

Principal components analysis (PCA) is a widely used technique in the social and physical sciences. However in spatial applications, standard PCA is frequently applied without any adaptation that accounts for important spatial effects. Such a naive application can be problematic as such effects often provide a more complete understanding of a given process. In this respect, standard PCA can be (a) replaced with a geographically weighted PCA (GWPCA), when we want to account for a certain spatial heterogeneity; (b) adapted to account for spatial autocorrelation in the spatial process; or (c) adapted with a specification that represents a mixture of both (a) and (b). In this article, we focus on implementation issues concerning the calibration, testing, interpretation and visualisation of the location-specific principal components from GWPCA. Here we initially consider the basics of (global) principal components, then consider the development of a locally weighted PCA (for the exploration of local subsets in attribute-space) and finally GWPCA. As an illustration of the use of GWPCA (with respect to the implementation issues we investigate), we apply this technique to a study of social structure in Greater Dublin, Ireland.     

入室盗窃多尺度地理因子分析

选取N市作为研究区域,以该市2013年全年的入室盗窃案件作为研究对象。将研究区域内入室盗窃与地理因子在不同空间尺度上进行关联性对比分析。首先,从环境犯罪学理论和现有犯罪地理特征研究两方面出发,分析现有研究中的尺度依赖性。每一套环境犯罪学理论均有其适用的空间尺度,在犯罪地理特征研究中会有相应的地理因子与之关联;其次,引入似不相关回归模型获取入室盗窃与地理因子在小区、街区、社区、街道以及区等多个空间尺度上的关联性。并用瓦尔德检验来测试各个关联系数之间差异的显著性。实验结果表明,随着尺度的变化,有些地理因子与入室盗窃的关联性并未变化,有些则发生了显著变化。这些变化可用不同尺度的犯罪地理学理论进行解释;最后,将多个尺度地理因子反演入室盗窃空间分布的结果进行综合,并将之与单一尺度的反演结果进行比较。结果证明,与单一尺度的地理因子反演犯罪空间分布的精度相比,利用多个尺度地理因子解释犯罪空间分布的精度更高。研究表明：在犯罪地理学研究中,环境犯罪学理论、地理因子分析以及犯罪空间分布反演均存在尺度依赖性。综合多个尺度的结果进行分析,不仅有利于准确认识犯罪的地理因子及其对应理论,对于犯罪反演精度也有所提高。     

地理学时空数据分析方法

随着地理空间观测数据的多年积累,地球环境、社会和健康数据监测能力的增强,地理信息系统和计算机网络的发展,时空数据集大量生成,时空数据分析实践呈现快速增长。本文对此进行了分析和归纳,总结了时空数据分析的7类主要方法,包括：时空数据可视化,目的是通过视觉启发假设和选择分析模型;空间统计指标的时序分析,反映空间格局随时间变化;时空变化指标,体现时空变化的综合统计量;时空格局和异常探测,揭示时空过程的不变和变化部分;时空插值,以获得未抽样点的数值;时空回归,建立因变量和解释变量之间的统计关系;时空过程建模,建立时空过程的机理数学模型;时空演化树,利用空间数据重建时空演化路径。通过简述这些方法的基本原理、输入输出、适用条件以及软件实现,为时空数据分析提供工具和方法手段。     

Likelihood analysis of earthquake catalogues

We apply several classes of stochastic multidimensional models to statistical analysis of earthquake catalogues using likelihood methods. We investigate the importance of including different earthquake parameters in the model: epicentral coordinates, hypocentral depth, time limits for interearthquake interaction, and especially spatial distribution of earthquakes as well as spatial aftershock patterns. Results of this study combined with other investigations, suggest that most distributions controlling earthquake interaction have a fractal or scale-invariant form. Developed models are used for statistical analysis of several earthquake catalogues to evaluate parameters of earthquake occurrence. These parameters are shown to be similar for shallow earthquakes of different magnitude ranges and seismogenic regions, confirming self-similarity of the earthquake process. Whereas intermediate earthquakes seem to emulate the pattern of shallow earthquake occurrence, albeit at a much smaller aftershock rate, deep earthquakes differ significantly in their properties. Predictability of standard shallow earthquake catalogues has been analysed; we present evidence that for the best available catalogues the predictability is close to 10 bits per earthquake. Several synthetic earthquake catalogues have been created and processed through the likelihood inversion scheme. The results from likelihood analysis of these catalogues confirm our approach.     

空间信息分析技术

在GIS技术日趋成熟和空间数据极大丰富的今天,通过分析空间数据探索空间过程机理正变得日益迫切。空间信息分析技术至少包括以下六个主要方面:(1)空间数据获取和预处理;(2)属性数据空间化和空间尺度转换;(3)空间信息探索分析;(4)地统计;(5)格数据分析;(6)复杂信息反演和预报。本文提出了解决具体应用问题一般的空间数据分析计算、结果解释和反馈程序。认为空间过程的一般共性和作为共同的研究对象,各种不同的方法技术最终可能导致空间数学(spatialmathematics)的产生,同时发展鲁棒的空间分析软件包对于普及空间数学是必要的。     

Geomagnetic lunar analysis by least-squares

Summary. A simple and accurate method is presented for the determination of lunar and solar harmonic terms present in a series of geomagnetic data. It is based on least-squares and incorporates a direct means for determining the confidence limits. The method is tested by applying it to a series of artificially generated data, and comparing the results both with the true answers and with results obtained using existing methods.     

Resolution analysis for discrete systems

summary . Treatments of geophysical inverse problems have tended to polarize into approaches intended to generate models either described by piecewise continuous functions or with some prior discretization. The two approaches are here developed in parallel, and the ideas of a trade-off between the anticipated error and the attainable level of detail in the model estimate are extended to the discrete case, either with even or uneven discretization.
An alternative approach to specifying the potential resolution of a model is to establish upper and lower bounds on parameter values. Linear programming methods are extended to determine bounds which allow for subjective limits on parameter values.
For a non-linear system the possible resolution may be investigated by estimation procedures based on the full set of successful solutions obtained by Monte-Carlo inversion.     

Attribute error and sensitivity analysis of map operations in geographical informations systems: suitability analysis

The theory and methods for attribute error and sensitivity analysis associated with map-based suitability analysis are developed. In particular, this paper delineates the underlying types of sensitivities for suitability analysis and derives ways to measure these sensitivities. Additionally, it shows how to undertake geographical sensitivity analyses given a generic geographical information system. The uses of these methods include understanding the relationship of the attribute errors in the output map generated by errors in the input maps for a given geographical analysis. This information provides a means to assess the quality and reliability of conclusions inferred from the output map created by such an analysis.     

Network-scape metric analysis: a new approach for the pattern analysis of urban road networks

The spatial patterns of road networks reflect the morphological and structural characteristics of cities. Previous studies have focused mainly on seeking universal laws in road networks rather than explaining their differences. A new approach for road network pattern analysis is proposed that has been inspired by landscape metric analysis. The utility of this approach is illustrated through (but is not limited to) the extraction of the main factors in network landscapes, or network-scapes for short. Twenty-four metrics were calculated for network-scapes of 100 cities worldwide, before an exploratory analysis is performed to detect the main factors. Four main factors were revealed and may be regarded as the characteristic indicators of road networks, which were identified to be evenness, richness-density, shape irregularity, and size and shape variation. The meanings of these factors are explained, and their spatial distributions are illustrated. Compared to existing road network analytics, these factors depict better the characteristic differences of road networks. The proposed approach provides a new framework for road network pattern analysis from a cellular perspective.     

城市老年人居家养老满意度的影响因子与社区差异

针对社区居家养老服务供给滞后、设施及服务功能单一、布局不合理等问题,基于北京市区内6 类典型社区的问卷调查数据,运用结构方程模型,构建了包含老年人居住环境因子在内的城市老年人居家养老满意度模型;并引入社会学及心理学常用的结构方程模型多群组分析(SEM Multiple-Group Analysis) 方法,以分析不同社区内各个老年特征群体的不同养老需求。分析结果表明：① 老年人的社会支持度(指来自家庭、朋友、邻里和社会的各种支援) 构成居家养老满意度的首要影响因子;② 社区养老服务发展程度对居家养老满意度的影响广泛而显著;③ 按照不同社区的居家养老模型及其影响路径特征,可将城市居住社区划分为居住环境影响型社区、基本因子影响型社区、社会环境影响型社区、社会环境+居住环境影响型社区等4 种类型,不同类型社区的老年人在居家养老需求方面具有显著差异。以上结果揭示了提升对老人的社会支持度的重要意义以及因地制宜完善社区居家养老服务的迫切性。     

新安江模型参数的不确定性分析

水文模型的不确定性研究是水文科学研究的重要课题。模型参数的不确定性分析是水文模型不确定性研究的重要内容之一。本文采用GLUE方法分析新安江模型参数的不确定性,结论基于对不同水文特征流域的长时间径流模拟,研究发现大量"等效性"参数组存在。据此将参数总结为三类:第一类为非敏感参数,如上层张力水容量UM等。它们对似然判据,及确定性系数(R²)影响小。第二类为敏感性参数,如河网蓄水消退系数CS等,其特点是对R²的影响大。第三类为区域性敏感参数,如张力水蓄水容量曲线的方次B等,它们对R²的影响力跟流域特征密切相关。这些结论有助于理解新安江模型参数,为今后流域水文模拟提供参考。文中还展望了未来水文模型不确定性研究的发展方向。     

乡村空间辨析

伴随着城镇化、信息化、全球化等多种内外因素的交互作用,中国的乡村正经历着社会经济形态重组、地域功能提升等一系列转型与重构的过程,乡村地域面临着前所未有的机遇与挑战,而“乡村振兴战略”的提出也给乡村发展及乡村地理学的研究提出了新要求,全面系统地认识乡村空间系统,准确把握乡村空间是开展进一步研究的必要前提。本文在系统梳理国内外对乡村空间的认知与发展基础上,指出国内乡村地理学在乡村社会—文化空间研究上的不足。本文以人地关系地域系统为理论基础,尝试建构了由“物质空间—社会空间—文化空间”组成的乡村空间系统,以期为全面认识日益复杂的乡村地域提供理论指导。