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161.
国内外铁矿石市场形势分析 总被引:2,自引:1,他引:2
铁矿石是钢铁工业稳健发展的基石。长期以来,我国铁矿石都处于供不应求状态,目前已经成为国际市场的最大买主,被号称为“全球吸铁石”。由于我国在国际市场上大量采购铁矿石,使得近年铁矿石价格变得扑朔迷离,为此付出了沉重的经济代价。为了更好地利用国外铁矿资源,更加理性地看待国内外铁矿石的供需问题,对国内外铁矿石的供需状况、进出口贸易及价格走势等市场方面的问题进行了分析,并提出了相应的政策建议。 相似文献
162.
In this paper, we map the gendered contours of contemporary water management in order to demonstrate that regimes for individual ownership of water rights, markets, and the productive use of water simply reinscribe and simultaneously submerge in their apparent gender-neutrality a normative masculinity that underpins economic globalization and fortifies existing power relations. Not only do such arrangements disadvantage reproductive values and non-consumptive users; more generally, they also lack the capacity to ensure water’s sustainable development. Consequently, new management institutions for sustainability are demanded and, in making a case for equity-enhancing and adaptive institutions that better reflect water’s materiality, its multiple values and emerging water scarcity, we argue the need to invoke the conserving and ecologically protective feminine principle. To support our reasoning, we analyse water reform processes instituted in Australia and specifically by the State of Tasmania, referring to the latter jurisdiction to illustrate the gendered nature of resource management and to underscore tensions between economic globalization and sustainability, concluding that the tensions between the two agendas are probably irresolvable. We position our work in the borderlands among gender studies, feminist geography and philosophy, and political ecology, drawing together insights about the construction of resource management, the possibilities of the feminine care ethic, and ideas about the characteristics of institutional systems that could ensure equitable allocation and sustainable use of the planet’s resources. 相似文献
163.
This paper is about a single event: a conference (A.K.A. ‘the health event’) held in the English East Midlands in July 2005, at which findings from a policy-led research project regarding young people’s health needs were fed back to research participants. The paper foregrounds some of the everyday work, happenings, emotions, conversations and materialities which were fundamentally constitutive of ‘the health event’ and, thus fundamentally constituted the moments of affirmative, politically-charged participation which could and did happen therein. Thus the paper bears witness to the sorts of practices, minutiae and highs and lows which are surely fundamentally constitutive of participation, policy and politics per se, but which (despite the growing visibility of nonrepresentational theories) are typically absent from salient accounts of participation, Children’s Geographies and Post-medical Geographies. 相似文献
164.
介绍了利用地面获取的单幅房屋近景影像计算房檐改正值的方法。该方法使用数码相机倾斜影像和房屋外观的几何约束条件,根据交比不变与透视旋转原理,确立了灭点、物方直线段与影像投影直线段之间的关系,并由此计算房檐宽度。实验结果表明,该方法能够满足实际需求。 相似文献
165.
Assessing the environmental impact due to consumption of goods and services is a pivotal step towards achieving the sustainable development goal related to responsible production and consumption (i.e. SDG 12). Household appliances plays a crucial role and should be assessed in a systemic manner, namely considering all life cycle stages, technological efficiency, and affluence aspects. The present study assess the impact of such household appliances used in Europe, and tests scenarios of potential impact reduction at various scales. Life cycle assessment is applied to 14 different household appliances (ranging from dishwashers to television devices) selected to build a set of representative products, based on their economic value and diffusion in households in Europe. Related impacts are calculated with the Environmental Footprint method for calculating a Consumer Footprint “appliances” for the baseline year 2010. A number of scenarios encompassing eco-solutions on a technical level, changes in consumption pattern, behavioral changes, as well as the combination of all these aspects are run to estimate the Consumer Footprint related to household appliances for the year 2030, compared against this baseline scenario. The baseline Consumer Footprint is confirming the importance of the use phase in leading the impacts in almost all impact categories. Testing different scenarios concludes that there is a reduction of the impact for most of the categories (with up to 67% for the ozone depletion potential, and still around 35% for the global warming potential), while two of the here examined impact categories (i.e. land-use and mineral resource depletion) show an overall potential that is even negative – i.e. the results of all scenarios are higher than the ones of the 2010 baseline scenario. The increase in purchase and use of such appliances may offset energy efficiency benefits in some of the examined categories. Hence, the assessment of sustainability of appliances consumption should always include several scales, from the efficiency of the products (micro scale), to the improvement of the energy mix (meso scale), up to accounting for socio-economic drivers and patterns of consumption affecting the overall appliances stock (macro scale). 相似文献
166.
杨万钟 《云南地理环境研究》1991,3(1):15-21
本文论述了产业结构、产业布局和产业政策一体化研究的辩证关系,指出经济地理必须拓展研究领域,不能局限于产业布局的狭窄范围内,而应把结构、布局和政策综合进行研究,才能提高研究成果的科学水平。产业结构和产业布局是一个事物的两个侧面,全国产业合理布局是优化产业结构的前提,地区产业结构合理化又是优化产业布局的前提。而加强产业政策研究又是实现产业结构和合理布局调整的必要保证。文内以上海市的实例进行系统分析与论述。 相似文献
167.
168.
The graphical representation and interactive manipulation of accurate three dimensional (3D) models of reality is rapidly becoming an inescapable necessity for many applications of geographical information systems (GIS). There are many problems and difficulties that must be overcome in order to facilitate such 3D models. Can accurate measurements, at sufficient resolution and using affordable resources, be obtained? Will application software usefully process, in all aspects, models of the real world, held in full 3D? Can a topology of containment, adjacency and contiguity in 3D be integrated into the conventional procedural and recording functionality of two dimensional (2D) GIS and still provide workable spatial analysis tools? A 3D GIS applied to an urban environment should maintain a model that would typically consist of solid representations of individual buildings, roads and utilities, providing both external and internal detail, all assigned to a suitable digital terrain model (DTM). The particular 3D application considered here addresses the need for accurate reconstruction of historical urban buildings. The creation, manipulation and exploration of such models is often referred to as “virtual heritage”. Much of this paper describes an effective methodology, called the Phoenix algorithm, requiring only a single image of an urban object, for the construction of 3D models of buildings at high resolution. The development of this algorithm is discussed and the results obtained from it are compared with those obtained using traditional 3D capture techniques. An outline of further potential GIS applications is presented. 相似文献
169.
自然地理学方向的古地理学开创了时间维地理学研究的领域,其在我国的发展经历了一个从古地理学向环境演变研究拓展的过程。以现代自然环境的历史建构为主体的古地理学,以时间坐标系下自然地理过程研究为主的环境演变研究,以从时间的维度探索人地关系为主的人地系统演变研究,分别体现了地理学的区域研究传统、地球科学传统和人地关系传统,构成了自然地理学时间维研究的3个基本方面。广义地理解自然地理学方向的古地理学、环境演变以及人地系统演变,它们可以看作是相通的,人地系统演变可以理解为包括了人类作为驱动力和承受者的环境演变,用人地关系来定义自然学地理方向的古地理学,则可以将其定义为关于人地(人类-环境)系统历史演变的科学。 相似文献
170.
赣东北中—新生代超基性岩与金刚石找矿前景 总被引:2,自引:0,他引:2
赣东北地区发现有中-新生代超基性岩。超基性岩侵入白垩系红色盆地中,主要有玻基辉橄岩、角砾状玻基辉橄岩等。角砾状玻基辉橄岩呈岩筒状。岩石化学分析结果显示,该处超基性岩中,SiO2含量为38.19%-44.28%,K2O+Na2O含量为2.01%-2.93%,MgO含量为7.67%-11.10%,CaO含量为8.25%-12.67%,Al2O3含量为11.94-14.51%,与曲型的玻基辉橄岩岩石化学成分相近。赣东北地区中-新生代超基性岩的发现,为重新分析评价赣东北地区金刚石找矿前景提供了重要的信息。 相似文献