地理学：从知识、科学到决策

地理学是研究地理要素或者地理综合体空间分布规律、时间演变过程和区域特征的一门学科,是自然科学与人文科学的交叉,具有综合性、交叉性和区域性的特点。随着地理信息技术发展与研究方法变革,新时期的地理学正在向地理科学进行华丽转身,研究主题更加强调陆地表层系统的综合研究,研究范式经历着从地理学知识描述、格局与过程耦合,向复杂人地系统的模拟和预测转变。在服务国内重大需求和国际全球战略过程中,地理学正在扮演愈发重要的角色,在新型城镇化、生态环境保护、水土资源管理、地缘政治等领域拥有广阔发展前景。中国地理学正面临前所未有的机遇,需要紧紧围绕国家重大需求,创新发展综合性的理论、方法和技术,逐步形成具有鲜明中国特色、深远国际影响的地理科学体系,为中国和全球的可持续发展服务。     

灾害范式及其历史演进

随着人类社会的发展,人类对灾害的理解发生了很大的变化,灾害范式也在不断的演进,可以归纳为：荒政范式、工程范式、行为范式、社会范式和可持续范式5种灾害范式。通过分析这些灾害范式形成的社会历史背景、灾害的基本观点、关注的主要问题以及减灾防灾的主要对策和措施,得出以下结论：① 在人类社会历史进程中,人们对灾害的认识和理解是逐步深化和发展的;② 灾害范式与减灾实践的发展是互动生成的;③ 范式的产生与转变都有深刻的社会动因;④ 一定时期,存在一定的主流灾害范式,但其他灾害范式的影响依然存在。     

Cranks, conventionalists and geomorphology

Hypotheses in geomorphology may be conventional or unconventional. It is argued that outrageous hypotheses produced by conventional thinkers with a streak of unconventionality occasionally shift paradigms and are invaluable alternatives to conventional hypotheses, which tend merely to shore up seemingly safe and secure ruling paradigms.     

空间信息的语言学概念模型

文章以空间信息与语言同为人类进行空间相关交流手段这一功能隐喻为基础,总结地图学、地理信息科学、知识工程等学科与语言学模型相关的理论研究成果,探讨空间信息语言学模型对地理信息科学发展的理论意义,包括学科范式观点、本体论观点、方法论观点和定性观点等方面的意义。     

THE EXPANSION METHOD: IMPLICATIONS FOR GEOGRAPHIC RESEARCH*

Geographic phenomena and our models of them are closely linked to the spatial-temporal contexts in which they are observed. The expansion method is a procedure that incorporates contextual effects into mathematical models. More importantly, it is the basis for a movement by some geographers away from the classical spatial science paradigm. The evolving paradigm associated with the expansion method represents a reformulation of the way in which geographers think about and use models, and is consistent with a more realistic perspective on the nature of geographic inquiry.     

When the pendulum doesn’t find its center: Environmental narratives,strategies, and forest policy change in the US Pacific Northwest

Since the 1980s, the US Pacific Northwest has been shattered by a major environmental policy conflict related to the management of Federal forests. These “timber wars” were similar to forest environmental policy conflicts in several other countries, but were particularly polarized. They resulted in a significant change in Federal forest policy from timber production orientation to biodiversity conservation. The change occurred suddenly and had significant economic and social consequences within the region and beyond, but was embedded in long-term societal and institutional trends.In this paper, I adopt an interpretive approach in order to, first, understand contemporary interpretations of the 1993 policy change and, second, to reconstruct the contemporary discursive ‘landscape’ of the Pacific Northwest including the major resource management paradigms and narratives that guide policy making in this region today. Empirically, my interpretation is mostly built on 37 qualitative interviews with policy stakeholders that were conducted in the summer of 2011.Based on this evidence, the paper argues that there are four narratives circulating amongst policy stakeholders that represent different conceptualizations of the 1993 policy change. Yet, all narratives highlight the importance of environmental strategy making that mobilized the socio-institutional setting in order to prepare and finally achieve the change.Current forest policy in the region is characterized by a policy stalemate resulting from the confluence of diverse institutional, context-related factors and the inability of stakeholders to create enough contradictions or crisis by combining these factors in order to promote change-enabling narratives. Four resource management paradigms compete in the region and, within these, narratives and counter narratives on physical and social events are developed. Current forest policy is dominated by an ecosystem management paradigm, but forest management practices aim to reconcile demands arising from the different paradigms to a certain degree, for instance via the concept of “ecological restoration”. Yet, given that the material base that feeds such compromises is finite, a new crisis in Pacific Northwest forest policy in the future is likely.In conclusion, this paper offers an interpretation of Pacific Northwest forest policy (change) as a process in which social and physical events are ‘discursively mobilized’ by means of narratives that are produced against the background of major natural resources paradigms. This includes the art of ‘discourse agents’ in constructing problematizations and intervention logics to either defend the current policy state or to increase the likelihood of change.     

A GRASS GIS parallel module for radio-propagation predictions

Geographical information systems are ideal candidates for the application of parallel programming techniques, mainly because they usually handle large data sets. To help us deal with complex calculations over such data sets, we investigated the performance constraints of a classic master–worker parallel paradigm over a message-passing communication model. To this end, we present a new approach that employs an external database in order to improve the calculation–communication overlap, thus reducing the idle times for the worker processes. The presented approach is implemented as part of a parallel radio-coverage prediction tool for the Geographic Resources Analysis Support System (GRASS) environment. The prediction calculation employs digital elevation models and land-usage data in order to analyze the radio coverage of a geographical area. We provide an extended analysis of the experimental results, which are based on real data from an Long Term Evolution (LTE) network currently deployed in Slovenia. Based on the results of the experiments, which were performed on a computer cluster, the new approach exhibits better scalability than the traditional master–worker approach. We successfully tackled real-world-sized data sets, while greatly reducing the processing time and saturating the hardware utilization.     

高分辨率遥感影像解译中的机器学习范式

高分辨率遥感影像解译是遥感信息处理领域的研究热点之一,在遥感大数据知识挖掘与智能化分析中起着至关重要的作用,具有重要的民用和军事应用价值.传统的高分辨率遥感影像解译通常采用人工目视解译方式,费时费力且精度低.所以,如何自动、高效地实现高分辨率遥感影像解译是亟待解决的问题.近年来,随着人工智能技术的飞速发展,采用机器学习...     

从溺谷湾到三角洲:现代珠江三角洲形成演变研究辨析

现代珠江三角洲经历了从溺谷湾到三角洲的形成演变,富有区域特色.本文提出百余年来珠江三角洲的研究可归纳为4种范式:历史描述、实地考察-学术推理、器测-学科理论和"动力-沉积-地貌"跨尺度范式,各以范例说明.基于笔者及其团队研究,对现有文献关于珠江三角洲形成演变若干重要观点提出不同意见并从多视角作必要辨析,包括:海侵盛期以...