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471.
Although viewed by business and commerce as successful solutions, geodemographic profiling of neighbourhoods has attracted wide-ranging criticism in the academic literature. This paper addresses some specific concerns that arise because the derivation of classifications is rarely transparent and open to scrutiny or challenge. The substantive focus of the research reported in this paper is a nationwide geodemographic classification of how people engage with new information and communication technologies (ICTs). In response to the critique of geodemographics as a ‘black box’ technology, we describe how the classification was opened up to public scrutiny and how we conducted a major consultation exercise into the reliability of its results. We assess the message of the 50,000+ searches and 3952 responses collected during the consultation exercise, in terms of possible systematic errors in the shape and detail of the classification. Unusually for Internet-based surveys, we also investigate the likely reliability of the response information received and identify ways in which the outcome of consultation might be used to improve the classification. We believe that this is the first-ever large-scale consultation survey of the validity and remit of a geodemographic classification and that it may have wider implications for the creation of geodemographic classifications.  相似文献   
472.
刘艳宾  弓小平  陈斌  王哲  吴艳爽 《地质学报》2012,86(6):1005-1019
结合地质、物探、化探、遥感等多元找矿信息,通过对多元信息的发现、提取、转换和关联,并利用信息综合技术建立区域综合信息矿产预测模型,进行矿产资源定量评价,是目前矿产资源勘查领域信息找矿的重要途径之一.本文从研究区的地质背景和已知的7个沉积变质型铁矿(点)出发,结合野外验证分析,建立成矿模型与有利区提取模型,基于ArcGI...  相似文献   
473.
Abstract Oxygen and hydrogen isotope analyses have been made of coexisting quartz, ilmenite, muscovite, and biotite from Late Precambrian metapelitic rocks, staurolite-kyanite to K-feldspar-muscovite-sillimanite zones, from Mica Creek, British Columbia. The δ18O and †D values of these minerals are generally uniform and do not decrease significantly with increasing metamorphic grade. This implies that there has not been significant infiltration of deep crustal, possibly magmatic, fluids into the metapelites that has been suggested for other high-grade metamorphic terranes. The uniformity of oxygen isotope compositions of the Mica Creek metapelite rocks may reflect isotopic uniformity in the sedimentary protolith rather than widespread exchange with an isotopically homogeneous metamorphic pore fluid.
Temperature estimates based upon 18O exchange thermometry for samples below the sillimanite zone are in reasonable agreement with the results of garnet-biotite Fe–Mg exchange thermometry. In the higher grade rocks, the oxygen isotope and garnet-biotite thermometry yield results which disagree by about 100°C. The highest temperatures recorded by oxygen isotope thermometry, 595°C, are at least 60°C below the minimum temperatures required by phase equilibria. These discrepancies appear to result from pervasive equilibrium retrograde exchange of oxygen isotopes between coexisting minerals. In addition, there are problems with calibration of garnet-biotite thermometry at higher temperatures. Retrograde oxygen isotope exchange may be a general characteristic of high-grade metamorphic rocks and oxygen isotope thermometry may not usually record peak metamorphic temperatures if they significantly exceed 600°C.  相似文献   
474.
Mike Raco 《Geoforum》2006,37(4):581-595
Spatial and planning policies in Britain have increasingly become focused on regional inequalities and the creation of mixed, sustainable and balanced communities. Within these new policy paradigms the category of the key workers has emerged as an essential element in the socio-economic sustainability of any bounded area programmes have been introduced to support their needs. Yet, defining key workers is an inherently political process as it necessitates the selection of essential and non-essential workers. Theoretical approaches that highlight state selectivity and the ways in which key policy subjects and objects are identified and mobilised have become increasingly popular across the social sciences and key worker support programmes provide a clear example of these processes in action. This paper draws on archival research to explore the formation of the category ‘key’ worker as an object of government in spatial development policies of the post-war period. It examines how key worker programmes were established to tackle the economic problems of Development Areas. It argues that definitions of key workers were forged in and through particular social, political, and economic contexts and that their emergence as an object of government presupposed and reinforced the existence of different classes of workers and different types of citizens. The paper highlights the significance of such historical work in assessments of contemporary policy and academic debates concerning the changing character of sustainable communities and citizenship, regional development, and changing modes of state regulation.  相似文献   
475.
塔河油田盐体覆盖区奥陶系储层发育特征及主控因素研究   总被引:2,自引:0,他引:2  
塔河盐下地区储层分布特征为奥陶系裂缝发育程度较高,溶蚀孔洞和半-未充填的高角度构造缝、溶蚀缝是本区最主要的储集空间类型.大型洞穴发育程度低于土体区,最主要的储集层类型为孔洞。裂缝型或裂缝-孔洞型储层.该区西部储层发育程度优于东部,本区有利储层多呈近NS条带状(或指状)展布;中下奥陶统上部储层发育程度高于下部;中下奥陶统储层发育程度高于上奥陶统良里塔格纽.控制盐下奥陶系储层发育与展布的主要因素是构造变形作用、加里东中期岩溶和沉积相.  相似文献   
476.
滇东北铅锌(银)成矿规律   总被引:2,自引:0,他引:2  
李才先 《云南地质》2005,24(3):275-281
滇东北铅锌(银)矿由峨眉山玄武岩喷发提供成矿热液,通过EW向构造导矿,NE—SW向构造控矿,在特定的岩性(碳酸盐岩)条件下形成,同一矿床又分脉状矿体(主要)、似层状矿体(次要),成因类型应为碳酸盐型中温热液矿床。  相似文献   
477.
苏文宁 《云南地质》2003,22(4):345-359
多年系统研究和大量样品检测证明:正确鉴别天然(A)、优化(B)翡翠玉件,比重、荧光是指示,结构是基础,识别充填物是关键,拉曼、红外作验证,综合分析下结论。而在常规仪器检测过程中,特别抓住结构(基础)、充填物(关键),即:用岩矿显微镜细致观察翡翠玉件结构,辅以针探和微区组分鉴别法区分各种充填物,结合比重、荧光检测结果,可以准确、快捷、经济地鉴别翡翠玉件A货、B货,而不需使用红外、拉曼。借助色源类型鉴别可正确鉴别处理翡翠玉件(C货)。  相似文献   
478.
乌鲁木齐市电业污闪的气象因素分析   总被引:1,自引:0,他引:1  
从认识电业污闪机理入手,了解乌鲁木齐地区气象条件对电业污闪发生的影响,进行污闪发生气象分析预防、预报,从而提出电业污闪的专业气象服务。  相似文献   
479.
尝试应用MAPGIS手段对新疆40年来的气温、积温、降水、蒸发等要素进行了一系列的计算、分析和制图。生成图像、数据可与其它应用系统进行信息交换、输出编辑图文并茂的应用产品。开拓性、探索性地开展气象服务信息化工作。  相似文献   
480.
介绍了新疆铁路大风监测系统的设计思路、系统结构、系统的特点及功能等研制情况。该系统在铁路安全运输中发挥了重要的作用。  相似文献   
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