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131.
信息时代到来 ,网络对人们的生活方式产生了深刻的影响。通过对网络社会、网络伦理的概念和现象的分析 ,尝试对当前存在的网络伦理危机和网络犯罪等问题进行初步的探讨。  相似文献   
132.
Reserves of some kinds of the crisis mines will be lack now or from now on, because of lacking seriously reserves of mineral resources and the crisis of exploring bases in support. So that it is urgent to predict, appraise, development and utilize the replaceable resources of the crisis mines. The mineral resources prediction software system of synthetic information is intelligent GIS which is used to quantitative prediction of large-scale synthetic information mineral target. It takes the geological body and the mineral resource body as a unit. And it analyzes the ore deposit genesis and metallotect, knows the spatial distribution laws of the ore deposit and ore body, and establish the prospecting modelbased on the concept of establishing the three-dimensional space of a mine. This paper will primarily discuss some important problems as follows: the secondary development of various kinds of data( including geology, geophysical prospecting, geochemical prospecting and remote sensing, etc); process synthetically and establish the synthetic information interpretative map base; correspond prospecting model with synthetic information of ore deposit; divided into statistical units of metallogenic information synthetic anomalies based on the synthetic information anomalies of ore control, then research the metallogenic information variable of unit synthetically and make quantitative prediction according to choose the quantitative prediction math model which is suitable to the demands of large-scale precision; at last, finish the target area optimization of ore deposit (body).  相似文献   
133.
Abstract

This paper provides an overview of the multiple ways of envisioning the relationships between maps and narratives. This is approached from a map making perspective. Throughout the process of editing this special issue, we have identified two main types of relationships. Firstly, maps have been used to represent the spatio-temporal structures of stories and their relationships with places. Oral, written and audio-visual stories have been mapped extensively. They raise some common cartographic challenges, such as improving the spatial expression of time, emotions, ambiguity, connotation, as well as the mixing of personal and global scales, real and fictional places, dream and reality, joy and pain. Secondly, the potential of maps as narratives and the importance of connecting the map with the complete mapping process through narratives is addressed. Although the potential of maps to tell stories has already been widely acknowledged, we emphasize the increasing recognition of the importance of developing narratives that critically describe the cartographic process and context in which maps unfold - the core idea of post-representational cartography. Telling the story about how maps are created and how they come to life in a broad social context and in the hands of their users has become a new challenge for mapmakers.  相似文献   
134.
Qualitative GIS and the visualization of narrative activity space data   总被引:1,自引:0,他引:1  
Qualitative activity space data, i.e. qualitative data associated with the routine locations and activities of individuals, are recognized as increasingly useful by researchers in the social and health sciences for investigating the influence of environment on human behavior. However, there has been little research on techniques for exploring qualitative activity space data. This research illustrates the theoretical principles of combining qualitative and quantitative data and methodologies within the context of geographic information systems (GIS), using visualization as the means of inquiry. Through the use of a prototype implementation of a visualization system for qualitative activity space data and its application in a case study of urban youth we show how these theoretical methodological principles are realized in applied research. The visualization system uses a variety of visual variables to simultaneously depict multiple qualitative and quantitative attributes of individuals' activity spaces. The visualization is applied to explore the activity spaces of a sample of urban youth participating in a study on the geographic and social contexts of adolescent substance use. Examples demonstrate how the visualization can be used to explore individual activity spaces to generate hypotheses, investigate statistical outliers, and explore activity space patterns among subject subgroups.  相似文献   
135.
The Indian economy suffered a balance of payment crisis in 1991, which provided the context for the rolling out of neoliberal policies, also referred to as the New Economic Policy in India. This paper examines the national and global causes and context of India's economic crisis and adoption of neoliberal policies. While grounding my analysis in historical‐geographical materialism, I argue that India's economic crisis was a product of certain contingent conditions. I draw attention to India's pre‐neoliberal economic regime and analyse how the earlier‐established relationship between revenue generation and expenditure ran into trouble; what changes occurred in the organization and management of revenues and capital; nature of interventions of the state in the circulation of capital; changes in the physical aspects of circulation of commodities, together with foreign trade and the formation of the ‘world market’; and the rise of the United States as the only global superpower. I conclude that India's economic crisis of 1990–91, and the neoliberal policies that followed, are products of contingent historical and geographical conditions. A teleological approach towards examining global capitalism and production of economic crisis often neglect such contingencies and provide a set of causalities that may, at best, be classified as incomplete.  相似文献   
136.
137.
Narrative analysis produces strategies to inform the conduct, interpretation and presentation of interview talk, and encourages and enables researchers to take account of research participants' own evaluations. We suggest this to be a useful method for geographers because it focuses on how people talk about and evaluate places, experiences and situations, as well as what they say. With an example from health geography, we show how it allows for interactive texts, thus providing a tool for geographers doing qualitative research to connect intimate details of experience to broader social and spatial relations.  相似文献   
138.
At the transition from the Permian to the Triassic, Eurasia was the site of voluminous flood-basalt extrusion and rifting. Major flood-basalt provinces occur in the Tunguska, Taymyr, Kuznetsk, Verkhoyansk–Vilyuy and Pechora areas, as well as in the South Chinese Emeishen area. Contemporaneous rift systems developed in the West Siberian, South Kara Sea and Pyasina–Khatanga areas, on the Scythian platform and in the West European and Arctic–North Atlantic domain. At the Permo–Triassic transition, major extensional stresses affected apparently Eurasia, and possibly also Pangea, as evidenced by the development of new rift systems. Contemporaneous flood-basalt activity, inducing a global environmental crisis, is interpreted as related to the impingement of major mantle plumes on the base of the Eurasian lithosphere. Moreover, the Permo–Triassic transition coincided with a period of regional uplift and erosion and a low-stand in sea level. Permo–Triassic rifting and mantle plume activity occurred together with a major reorganization of plate boundaries and plate kinematics that marked the transition from the assembly of Pangea to its break-up. This plate reorganization was possibly associated with a reorganization of the global mantle convection system. On the base of the geological record, we recognize short-lived and long-lived plumes with a duration of magmatic activity of some 10–20 million years and 100–150 million years, respectively. The Permo–Triassic Siberian and Emeishan flood-basalt provinces are good examples of “short-lived” plumes, which contrast with such “long lived” plumes as those of Iceland and Hawaii. The global record indicates that mantle plume activity occurred episodically. Purely empirical considerations indicate that times of major mantle plume activity are associated with periods of global mantle convection reorganization during which thermally driven mantle convection is not fully able to facilitate the necessary heat transfer from the core of the Earth to its surface. In this respect, we distinguish between two geodynamically different scenarios for major plume activity. The major Permo–Triassic plume event followed the assembly Pangea and the detachment of deep-seated subduction slabs from the lithosphere. The Early–Middle Cretaceous major plume event, as well as the terminal–Cretaceous–Paleocene plume event, followed a sharp acceleration of global sea-floor spreading rates and the insertion of new subduction zone slabs deep into the mantle. We conclude that global plate kinematics, driven by mantle convection, have a bearing on the development of major mantle plumes and, to a degree, also on the pattern of related flood-basalt magmatism.  相似文献   
139.
再论我国耕地的保护和完善保护机制的问题   总被引:2,自引:4,他引:2  
陈朝辉 《热带地理》2002,22(3):253-256
耕地是保证社会经济发展最重要的自然资源,由于耕地必须具备特殊的自然条件。因而决定其数量的有限性,在人多地少的我国,保护好耕地尤为重要,目前我国耕地安全存在严重危机,必须采取有效措施使之得到切实保护,以保证我国社会经济的顺利发展。  相似文献   
140.
An extended narrative dataset of the Medieval time AD 708-1426 in continental western Europe was set up. Some 30-year-moving mean seasonal temperature deviation series were reconstructed. A- warming trend occurred around AD 1200. During the warm stage, seasonal cycle might be weak due to frequent cool summers. Significant warm summer conditions did not occur until the late 14th century, when the annual temperature level began decreasing. The mean warm season temperature level during the late 14th to the early 15th century might be about 0.3°C higher than the present. It was suggested to cautiously comment on historical climates for different seasons.  相似文献   
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