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231.
This paper considers whether the deployment of a topographical metaphor may add value to the recent discussion of networked relations. The paper discusses how viewing relations as part of a relational landscape may add a third dimension to the discussion by allowing an appreciation of the strength, or entrenchment, of relations, and how these entrenchments impact on the development of new relations and the resistance to watershed events. The heuristic device is explored through the case of air survey in the 1920s and 1930s. This illustrative case demonstrates how relations are held together, resisted and reformed to different degrees depending on the varying topography of the relational landscape. 相似文献
232.
In this paper, we examine the development and implementation of new technical systems designed to more effectively manage and produce driving, drivers and driving spaces. These new systems change the governmentality of automobilities by altering the relationship between driver, vehicle and transport infrastructure and produce new subjects and spaces. They do this principally through the process of automation, creating a system of regulation that we term ‘automated management’. Automated management consists of two interlocking sets of regulatory technologies: automated surveillance that seeks to enforce more effective (self)disciplining and capture systems that actively reshape activity. We argue that these work together to alter the automobilities landscape creating new socio-spatial arrangements with respect to access, movement, flow, and behaviour. Some of these arrangements are benign and empowering to individuals, others enhance the power of state and corporations. We illustrate our argument with examples predominately drawn from the UK, though the technologies we discuss are increasingly being developed and implemented throughout Western countries and beyond. 相似文献
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234.
A micromorphologically based pedosedimentary reconstruction of a 40‐m loess–palaeosol sequence from the western part of the Chinese Loess Plateau provides a sensitive proxy record of changing processes and associated environmental conditions in this region between ca. 150 000 and 10 000 yr BP. Depth functions of more traditional climate proxies, such as magnetic susceptibility, calcium carbonate content and median grain size, support the broad pattern of environmental changes inferred from the micromorphology, although the bulk properties sometimes lag behind or are out of phase with each other and do not match all the fluctuations in the micromorphological record. The reasons for the disparities are probably complex, although they partly reflect differences in response rates and sensitivities of proxies to different climate parameters, as well as genuine out‐of‐phase changes in strength of monsoonal climate controls. This work illustrates the sensitivity of micromorphology in detecting past environmental changes within rapidly aggrading landscapes, and emphasises the need to understand more fully the local and regional significance of bulk proxies currently used in global correlations with marine‐ and ice‐core records. Copyright © 1999 John Wiley & Sons, Ltd. 相似文献
235.
This paper presents a critique of current methods of sampling and analyzing soils for metals in archaeological prospection. Commonly used methodologies in soil science are shown to be suitable for archaeological investigations, with a concomitant improvement in their resolution. Understanding the soil‐fraction location, concentration range, and spatial distribution of autochthonous (native) soil metals is shown to be a vital precursor to archaeological‐site investigations, as this is the background upon which anthropogenic deposition takes place. Nested sampling is suggested as the most cost‐effective method of investigating the spatial variability in the autochthonous metal concentrations. The use of the appropriate soil horizon (or sampling depth) and point sampling are critical in the preparation of a sampling regime. Simultaneous extraction is proposed as the most efficient method of identifying the location and eventual fate of autochthonous and anthropogenic metals, respectively. © 2004 Wiley Periodicals, Inc. 相似文献
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237.
Barend Köbben Rolf De By Theodor Foerster Otto Huisman Rob Lemmens Javier Morales 《Transactions in GIS》2010,14(Z1):25-37
ITC, the Faculty of Geo–Information Science and Earth Observation of the University of Twente, is an institute that aims at capacity building and institutional development, specifically in developing countries. In our Geoinformatics curriculum, we emphasise two principles. The first addresses the systematics of purposeful spatial data production and uptake into computerised systems; the second addresses the methodical construction of these computerised systems, applying principles of model – driven architecture, formal specification and transformational design of SDI nodes. The term Spatial Data Infrastructure (SDI) usually denotes large, complex systems, but its principles can also be applied in simple and cost–effective ways. This approach we have called SDIlight and it is of particular interest to our students that come from developing countries. We work with and build a software stack consisting of free and open source components. To achieve interoperability, we emphasise the use of open standards from the Open Geospatial Consortium and others. In this paper, we explain how our students apply the SDIlight approach in the GeoinformaticsMaster degree course. An important part of that course is a Case Study Application Building & Programming, in which students apply their knowledge in a ‘real–world’ project, with a focus on geo–information engineering skills. We conclude with a section that evaluates the effectiveness of using the SDIlight concept in teaching our Geoinformatics Master, and on the more general applicability of the methodology. 相似文献
238.
There are a number of techniques for estimating the amount of weathering a clast has undergone. These usually have the objective of establishing an ordinal chronology of geomorphological surfaces, or investigation of site-specific conditions affecting weathering rates. Three such techniques are applied to a dated sequence of alluvial fan segments in southern Tunisia. Two of these techniques depend on measuring surface roughness (the micro-roughness meter and a displacement approach) and one uses the structural weakening of the rock fabric (Schmidt hammer). The micro-roughness meter enables calculation of standard deviation of surface height variation, root mean square roughness and surface autocorrelation function. Of these techniques, Schmidt hammer rebound values, standard deviation, root mean square roughness and the displacement technique show systematic changes on the three fan segments which are statistically significant at the 0·05 level. However, the amount of variance in all datasets is very large, indicating the need for caution in application of these techniques for relative dating. © 1998 John Wiley & Sons, Ltd. 相似文献
239.
The pedogenic histories of four adjacent profiles of a polygenetic palaeosol developed on a Middle Pleistocene terrace of the proto-Thames from Wivenhoe in southeast England are reconstructed on the basis of superposition of key micromorphological features. Despite a considerable variation in macromorphology, partly resulting from large-scale periglacial features, three of the profiles have similar micromorphological records in that they retain evidence for two phases of clay illuviation separated by a period of periglacial disruption. This reconstruction, however, seems to be incomplete because the fourth profile contains micromorphological evidence for a further illuviation–disruption cycle. The extent of this variation suggests that soil micromorphology should be used only with care to reconstruct pedogenic or pedosedimentary histories of complex polygenetic palaeosols, or to compare such palaeosols on different surfaces of chronosequences spanning periods of major climatic change. The variable and possibly limited resolution of micromorphology, together with the current uncertainty over the exact environmental signifiance of illuvial clay features, means that inferred pedogenic phases should be correlated with specific climatic stages only with considerable caution. © 1998 John Wiley & Sons, Ltd. 相似文献
240.