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541.
With the ever-accelerating economic and social growth in Asia, the sustainable development of environment, economy and society of Asia and beyond, is severely constrained by a series of grave issues, such as global climate change, population explosion, resource shortage, and rampant disasters. The need for study on groundwater resources and environment in Asia as part of the efforts to tackle global climate change looms even larger. In analyzing how global changes of modern times and human activities are related to primary geo-environment, the groundwater environment serial maps of Asia introduces a new concept for mapping geo-environment of Asia that connects the geological background to groundwater environment. The serial maps reveal the geographic environment that is closely related to groundwater, the special-temporal features of the geo-environment and how it is distributed. The study is vital not only to the harmonious development among environment, economy and society as well as ecological progress in Asia, but also to the strategic requirements posed by the “One Belt One Road”. 相似文献
542.
将意识层面的空间意象外化为可被度量及分析的对象,一直是行为学、地理学、旅游学等学科关注的重要课题。本文主要从构建空间意象的结构而非意义入手,对该领域研究中的两种重要方法,即认知地图法和空间句法进行了比较,意图找到两种方法在空间结构性认知方面的相关性。基于句法空间结构的表达模型,分别就长沙太平街历史街区集成度及其认知地图的调研结果进行了比对,通过真实地图句法集成度与579 份认知地图意象要素出现频率等指标的比较,发现集成度指标与意象出现频率等指标存在较好的相关性。在对认知地图样本进行轴线化转换并比照真实地图的轴线索引后,对真实地图句法集成度与579 份认知地图平均句法集成度进行比较,发现认知地图与真实地图的句法分析在结果上仍有较好的相关性,且节点、标志物两要素的出现频次等指标也与所在街道的集成度存在较为明显的对应性。结论说明空间构形对人们结构性意象的形成有着重要的影响力,认知地图的句法分析对揭示人们空间知识的形成机制具有一定的参考价值,两种方法有相互补充的可能性。 相似文献
543.
Different models were developed for evaluating the probabilistic three-dimensional (3-D) stability analysis of earth slopes
and embankments under earthquake loading using both the safety factor and the displacement criteria of slope failure. In the
3-D analysis, the critical and total slope widths become two new and important parameters. The probabilistic models evaluate
the probability of failure under seismic loading and consider the different sources of uncertainties involved in the problem,
i.e. uncertainties stemming from the discrepancies between laboratory-measured and in situ values of shear strength parameters,
randomness of earthquake occurrence, and earthquake-induced acceleration. The models also take into consideration the spatial
variabilities and correlations of soil properties. The developed models are incorporated in a computer program, PTDDSSA (probabilistic
three-dimensional dynamic slope stability analysis). These developed analysis/design procedures are incorporated within a
code named SARETL (stability analysis and remediation of earthquake-triggered landslides) that was developed in this study
for stability analysis and remediation of earthquake-triggered landslides. In addition to the dynamic inertia forces; the
developed system takes into consideration the local site effects. The code is capable of: 1. Prediction of permanent deformations
that result from landslides under seismic loading using both probabilistic and deterministic approaches. 2. The assessment
of landslide hazard that affects major transportation routes in the event of earthquakes, and the preparation of earthquake-induced
landslide hazard maps (i.e. maps that show expected displacements and probability of slope/embankments failure) for different
earthquakes magnitudes and environmental conditions. 3. Proposing a mitigation strategy against landslides and suggesting
guidelines for remedial measures. The developed expert system is applied to a major highway case study. Design maps are developed
for the highway under seismic loading.
Received: 18 March 1999 · Accepted: 11 October 1999 相似文献
544.
建立沙漠化环境监测信息系统图形数据库专题系列地图的编辑与制图 总被引:1,自引:0,他引:1
沙漠化专题系列地图是沙漠化环境信息系统图形数据库的主要信息内容, 目的在于为系统进行空间分析提供数据。沙漠化系列图的编制, 因制图工具是具有图形编辑软件的计算机系统, 地图载体已改变为磁性记录媒体, 制图程序与常规方法差别甚大。本文结合机助制图特点, 介绍了制图编辑中的有关问题, 主要内容包括:(1)用于沙漠化环境监测信息系统专题地图的设计; (2)专题系列地图的制图分类; (3)图形数据库中专题系列图的统一协调; (4)系统中沙漠化专题系列图的编辑特点; (5)沙漠化环境信息系统中系列图件的时间序列。 相似文献
545.
546.
顾及尺度效应和景观格局的土地利用数据综合指标研究 总被引:6,自引:0,他引:6
从尺度效应和土地利用案观格局影响两个层面研究土地利用数据综合的宏观和微观综合指标,设计土地利用数据综合的指标体系和指标定量化描述模型.在全国各个土地利用分区采集不同尺度的具有典型代表性的土地利用数据样本集,通过空间统计分析等方法,得到土地利用数据综合中的宏观控制性指标和微观图形综合指标的尺度变化规律及其与土地利用格局的关系.以一个县为试验区,验证其合理性.Abstract: Indices for land use data generalization are critical for generating multiscale land use maps and databases. Previous research suffers from two major setbacks. Firstly, determination of threshold values for multi-scale land use data generalization in a large area, such as a nation, remains subjective. A second problem is general ignorance of landscape pattern. This paper studies the index system of land use data generalization from both scale and landscape pattern perspective. We discuss the macro and micro indices of land use data generalization with consideration of spatial scales and landscape pattern. To quantitatively relate the indices and scale and landscape pattern metrics, land use data samples have been collected at multiple spatial scales in various land use regions across China. Based on statistic analysis, we then generate both macro and micro control rules for land use data generalization at various spatial scales and land use patterns. Finally, we prove the proposed method and achieved results to be effective and reasonable with sample data at county level. 相似文献
547.
Jamal Jokar Arsanjani 《International Journal of Digital Earth》2019,12(6):642-660
Global land cover maps are important sources of information for a wide range of studies including land change analysis and climate change research. While the global land cover maps attempt to present a consistent and homogenous data in terms of the production process, the existing datasets offer coarse resolution data, e.g. 1000 m for IGBP DISCover and 300 m for GlobeCover 2009 that is oftentimes challenging. Recently, GlobeLand30 data based on Landsat archive for two timestamps of 2000 and 2010 has been released. It presents a finer spatial resolution of 30 m, which provides numerous opportunities for a wide range of studies. The main objective of this study is to use this dataset for characterizing global land cover patterns, monitoring, and identifying extreme land change cases with their types and magnitude. The findings reveal massive land change patterns including deforestation, desertification, shrinkage of water bodies, and urbanization across the globe. The results and discussions of this research can help policy-makers, environmental planners, ecosystem services providers and climate change researchers to gain finer insights about the forms of global land change. Future research calls for further investigation of the underlying causes of the massive changes and their consequences on our ecosystems and human populations. 相似文献
548.
The visual analysis of remote sensing imagery is useful for the extraction of information not readily available through automated image analysis. Previous studies have shown that the replication of human reasoning about image content is difficult due to human creativity and mental flexibility. Development of automated image analysis programs continues; however, geovisual analytics suggests that it may be more beneficial to design symbiotic computer-human interpretation systems. It is imperative to understand the experiences, knowledge, and cognitive processes that image interpreters rely on. Cognitive Task Analysis (CTA) is a methodological framework developed from Cognitive Systems Engineering (CSE) where expert users are studied with the goals of explicating their needs, wants, and cognitive abilities for dealing with complex technological systems. Here we report the results of a CTA process carried out with users of a geovisual analytic tool to support forest disturbance detection and signification. These results suggest that different facets of the cognitive processes undertaken by users are not always explicit, and differences in the participant’s attentiveness to their mental processes vary greatly. Despite these differences and pathways to their final interpretations, participants were able to successfully come to similar judgments as for their peers. 相似文献
549.
This article deals with the cartometric analysis of various seventeenth-century urban maps of the city of Cadiz (Spain), from among which the so-called Vista Arámburu and the map belonging to the atlas of the Marquis of Heliche, discovered in the Krigsarkivet (Military Archive) of Stockholm, stand out for their uniqueness. These hitherto relatively unknown documents present evidence of an evolution of cartographic style towards greater topographic accuracy and hence cannot just be considered as simple drawings. In this seventeenth-century period of transition, the cartography of the city evolved from sixteenth-century aerial-view perspectives to the exhaustive planimetric maps of the eighteenth century, made by Spanish and French Military Corps of Engineers. These documents hold great historical value, not only due to the importance of Cadiz during the Modern Age but also because these maps constitute a graphic testimony of the fortification and growth of the city in this period. 相似文献
550.