二维空间关系定性表达模型的研究

通过对几种典型的定性表达模型的分析及比较,论述了单一模型实现空间查询所存在的局限,提出利用组合模型来表达空间关系的方法。最后结合空间查询中的实例,通过介绍如何同时运用二值拓扑关系模型和符号空间索引模型来实现同时包含拓扑关系和方向关系的复杂空间查询来说明这种方法。     

基于数值模拟和统计拟合分析华北冬季一次大范围重污染过程的形成机理

基于WRF/Chem（Weather Research Forecasting/Chemistry）模式对2015年11月25日至12月2日我国北方一次大范围PM2.5（空气动力学当量直径小于等于2.5 μm的颗粒物,即细颗粒物）重污染过程进行了模拟。与观测资料对比表明,模式能够较好地模拟出PM2.5浓度及气象因素的变化趋势,结果适用于此次污染事件的机理分析。动力、热力条件及化学转化等因素对此次强污染事件形成的机理分析表明,动力因子主要通过表面风和垂直风切变的减弱对此次污染事件造成影响,边界层逆温等热力因子促进了大气稳定性的增强,不利于污染物扩散。依据PM2.5组成成分变化分析可知,硝酸盐、硫酸盐和有机碳在此次事件中含量增加,说明机动车汽车尾气和燃煤排放所致的二次气溶胶生成对PM2.5污染加剧起重要贡献。多元线性回归分析和多因子相对贡献率量化解析结果表明,热力因子在此次污染过程中起主要作用,方差贡献率为52%,动力因子次之,方差贡献率为34%,而化学转化方差贡献率约为14%,说明气象条件,尤其是热力条件是引起此次污染事件的主要原因。     

基于事件数据的雅鲁藏布江-布拉马普特拉河国际河流安全分析

雅鲁藏布江-布拉马普特拉河是我国重要的国际河流,近年的水电开发活动,使其日益成为国内外国际河流研究关注的热点。本文基于国际关系研究中常用的事件分析方法,在构建事件数据库的基础上,从事件类型、涉及国别、事件频率、影响程度四方面进行分析,结果表明：水资源分配问题是雅江流域主要问题;中国在雅江国际河流问题上与下游国家的联系主要以与印度或孟加拉国的双边联系为主;随着时间的推移,雅江冲突与合作事件的频率都表现出增加的趋势;雅江围绕国际河流的国际关系局势大致可分为4个阶段：60年代的平稳阶段、70年代的紧张阶段、80年代的沉寂阶段、90年代后的持续关注阶段。     

Phenomenological model of phase transformations of gas hydrates in porous media: Visco-plastic consolidated skeleton

We develop a phenomenological model to describe the behavior of natural porous media saturated with phases that can experience phase transformations which result in changes of the strength, rheology, and transport properties of the medium. A porous medium saturated with gas hydrates cementing the grains of a mineral skeleton is an example of such behavior. On a decrease in pressure or increase in temperature, hydrates in such a medium dissociate into gas and water. The resulting fluid acts as a lubricant between the skeleton grains: the elastic response is changed by the viscous response, and the processes of consolidation and multiphase filtration in the deforming skeleton are initiated.     

On the relevancy of the combination of macroseismic and paleoseismic data

Earthquakes that occurred in the Baikal seismic region in 1725, 1742, 1769, and 1829 are studied on the basis of original macroseismic information. Due to the fact that their parameters were previously determined using the combination of macroseismic and paleoseismic data, the goal of our investigation is to verify how well the solutions agree with the macroseismic evidence. Careful examination of macroseismic data includes, first of all, the searching for original sources, which cannot be replaced by any other data types, for instance, paleoseismic information characterized by questionable reliability. The completeness of analysis is achieved when different components are inspected separately before mixing. In the case when unequivocal data interpretation is impossible, it is better to consider different alternative solutions characterized by relatively narrow error ranges. Variants can be weighted correspondingly (at least, evaluated qualitatively). Otherwise we have to deal with the so-called “average” solutions, often useless due to great determination errors. Magnitudes of all earthquakes estimated previously on the basis of macroseismic and paleoseismic data are not confirmed by the original macroseismic information, and revised magnitudes are essentially lower.     

The development of the system of integrated instrumental monitoring of volcanoes in the Far East Region

This work presents the project of the first stage of implementation of the integrated instrumental system of volcanic activity monitoring in Kamchatka and the Kuril Islands. The system of monitoring was designed for the purpose of ensuring public safety, aviation safety, and reducing economic losses caused by volcanic eruptions. The most active and dangerous volcanoes in Kamchatka (North and Avacha groups of volcanoes) and the Kuril Islands (volcanoes on the islands of Kunashir and Paramushir) are of first priority for monitoring. For this purpose, special observation points are planned to be installed on the volcanoes. The system of monitoring will include a complex of observations (broadband seismic station with a large dynamic range, tiltmeter, devices for gas, acoustic, and electromagnetic observations, and video camera). All the data will be passed to information processing centers in real time. New methods and algorithms of automatic and automated identification of the volcanic activity level and the probabilistic volcano hazard assessment have been developed.     

Diurnal periodicity of the representative earthquakes in Greece

The diurnal periodicity of seismic events of different energy from the Greece earthquake catalog was studied. Earthquake samplings of different energy with a known level of magnitude of completeness were compiled. Parameters of the diurnal periodicity of earthquakes in different time and magnitude intervals were analyzed. Significant diurnal periodicity of earthquakes with M ≤ 4.1 was revealed. The most important result of the paper is the discovery of the diurnal periodicity of the representative earthquakes with M = 3.2–4.1. The diurnal periodicity of representative earthquakes cannot be explained at the base of the prevailing hypothesis considering the diurnal periodicity of earthquakes as an apparent phenomenon resulting from diurnal changes in the real sensitivity of the seismic network due to diurnal variations of seismic noise.     

Natural-resource space: Differentiation, boundaries, types

Natural-resource space (NRS) is a set of resource-containing components of geographical environment as taken in a spatiotemporal continuum. We suggest different types and levels of NRS: global, national, regional and local; space of homogeneous resources, and territorial combinations of natural resources, and others. Borders are identified as really existing transitional zones between NRS of different types and levels, and institutional boundaries. Ecological-resource space is singled out, given a connectivity of national and regional NRS, with portions of transboundary geosystems going beyond their boundaries.     

重庆及邻区震后烈度分布评估模型构建

选取重庆及邻区作为研究区域,将典型历史地震震例的等震线图数字化,通过回归分析分别构建了基于烈度衰减关系的烈度分布评估模型、基于等震线长短轴半径的“王景来”烈度分布评估模型和基于面积的烈度分布评估模型.最后利用算例验证了上述三种模型的适用性.震后烈度分布评估模型对于震后灾害损失评估有重要的意义.