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Flood insurance: the challenge of the uninsured   总被引:1,自引:0,他引:1  
Increasing concern about flooding and its potentially socially-devastating effects has reinforced the need for an effective mechanism to deal with the recovery of losses from these events. This paper highlights the problem of uninsurance in the UK and the potentially growing number of people who do not have flood insurance. A dual challenge of uninsurance is emerging: those who have been traditionally excluded from insurance cover due to price and a new phenomenon, those who live in high-risk areas who may become cost-prohibited through the introduction of risk-related premiums.  相似文献   

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This paper examines the strength of Western Australia's claim to be ‘the resource state’. It traces the history of the state's mineral development and points to close links between the development, the growth of the economy and the spread of settlement. The crucial role of the state government in facilitating capital investment and fostering a growth ideology is also highlighted. The paper argues that while resource development and capital investment have brought tangible economic benefits to Western Australia and the nation, certain costs have also been generated. Growth has caused damage to the physical environment and the once‐numerous Aboriginal population. Moreover, given the international commodity crisis of the 1980s, mineral export strength is no sure recipe for economic success.  相似文献   

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Earthquake prediction: the null hypothesis   总被引:5,自引:0,他引:5  
The null hypothesis in assessing earthquake predictions is often, loosely speaking, that the successful predictions are chance coincidences. To make this more precise requires specifying a chance model for the predictions and/or the seismicity. The null hypothesis tends to be rejected not only when the predictions have merit, but also when the chance model is inappropriate. In one standard approach, the seismicity is taken to be random and the predictions are held fixed. 'Conditioning' on the predictions this way tends to reject the null hypothesis even when it is true, if the predictions depend on the seismicity history. An approach that seems less likely to yield erroneous conclusions is to compare the predictions with the predictions of a 'sensible' random prediction algorithm that uses seismicity up to time t to predict what will happen after time t. The null hypothesis is then that the predictions are no better than those of the random algorithm. Significance levels can be assigned to this test in a more satisfactory way, because the distribution of the success rate of the random predictions is under our control. Failure to reject the null hypothesis indicates that there is no evidence that any extra-seismic information the predictor uses (electrical signals for example) helps to predict earthquakes.  相似文献   

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《The Journal of geography》2012,111(3):95-103
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Thematic maps reveal the geography of any area. A series of such maps introduces the growth, landforms, railroad lines, African-American population, population density, and population change in Chicago. Many of these patterns have been laid down in past times, but they also influence present and future trends.  相似文献   

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The growth of Australian cities was the most prominent aspect of Australia's development during the boom years from the end of World War Two. As the nation pursued a policy of import substitution, the economies of the cities became firmly based on manufacturing. Mass production methods and mass consumption dictated the pattern of urban development. Such growth was premissed on very special conditions that enabled the system to accommodate the fluctuations that inevitably occur within the capitalist mode of production in general, and mass production methods in particular. A nation which had always been highly urbanised and open to international influences became even more deeply enmeshed in the fluctuating fortunes of the global economy. As the special factors supporting the postwar prosperity broke down through the 1970s and 1980s, Australian cities have faced a number of critical problems of adapting to the new environment.  相似文献   

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尹梁明  殷清眉  徐建华  叶超 《地理研究》2018,37(10):2087-2095
地理学思想史研究和教学对学科发展意义重大。地理学发展过程中既有寻求一般性理论的传统,也有对地方特性的强调,二者间的紧张关系是地理学思想史的一个主调。尤其是第二次世界大战之后,实证主义、人文主义、马克思主义、女性主义、后现代、后结构、后人文、关系地理学等众多学派涌现,其核心争论正是追求一般性还是特殊性。聚焦该问题,以《地理学思想:批判性导论》一书为典型案例,通过梳理地理学思想流派更迭的简史,总结一般性和特殊性之间的辩证互动关系,并指出未来中国地理学思想研究和教育的核心在于批判性。只有通过批判性思考和实践,才能更深入地了解学科性质及其演变历程,才能更好地进行学术普及和理论创新。  相似文献   

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《The Journal of geography》2012,111(4):459-461
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How will the National Geography Standards change the way teachers teach? The Standards will provide teachers with a geographic perspective that will enable them to teach improved geography content while building geographic skills and knowledge that will benefit their students for the rest of their lives. By taking a fresh look at the content in the curriculum from a geographic perspective, teachers can make connections between the Geography Standards and our own classrooms. The Standards provide information and strategies for teaching geography. They can be used to create lessons which offer opportunities for students to “do” geography and apply the skills they are learning.  相似文献   

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In May this year, a Briton named Alex Hartley gamely claimed as his personal territory a tiny island in Svalbard that had been revealed by retreating ice. Svalbard's islands have a long history of claims and counter-claims by adventurers of diverse nations: the question of who owns the Arctic is an old one. In this next article in our unreviewed biographical/historical series, Frode Skarstein describes Norway's bid to wrest a corner of Greenland from the Danish crown 75 years ago.  相似文献   

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Viewshed analysis remains one of the most popular GIS tools for assessing visibility, despite the recognition of several limitations when quantifying visibility from a human perspective. The visual significance of terrain is heavily influenced by the vertical dimension (i.e. slope, aspect and elevation) and distance from the observer, neither of which are adjusted for in standard viewshed analyses. Based on these limitations, this study aimed to develop a methodology which extends the standard viewshed to represent visible landscape as more realistically perceived by a human, called the ‘Vertical Visibility Index’ (VVI). This method was intended to overcome the primary limitations of the standard viewshed by calculating the vertical degrees of visibility between the eye-level of a human and the top and bottom point of each visible cell in a viewshed. Next, the validity of the VVI was assessed using two comparison methods: 1) the known proportion of vegetation visible as assessed through imagery for 10 locations; and 2) standard viewshed analysis for 50 viewpoints in an urban setting. While positive, significant correlations were observed between the VVI values and both comparators, the correlation was strongest between the VVI values and the image verified, known values (r = 0.863, p = 0.001). The validation results indicate that the VVI is a valid method which can be used as an improvement on standard viewshed analyses for the accurate representation of landscape visibility from a human perspective.  相似文献   

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The Israeli Desert constitutes 60% of the country's total area. Regional annual precipitation is 100–200 mm and evaporation reaches 2,500 mm. Traditional desert agriculture of rain fed wheat and sheep, goat and camels grazing is common. Despite the harsh climate conditions, advance agriculture is concentrated in foci where water resources exist. Desert agriculture takes advantage of the winter(October–April) due to a mild climate season for growing vegetables, flowers, herbs and fruit which are mostly exported to European countries. The key factor is the sustainable management of the local natural resources. The regional research and development(RD) system is generating adequate local knowledge and technologies. The most important key factor is developing water resources, and using irrigation saving water systems such as drip irrigation. Technologies of protected agriculture such as greenhouses and plastic tunnels are used. The unfit desert soil is substitute by sand and artificial growing media. For gaining market purposes, introduction of botanical species was implemented for various flowers and vegetable varieties, avocado, pitaya, and jojoba. Controlled drip irrigation and drainage helps to solve salinity problems. Integrated Pest Management(IPM) is used to overcome plant protection issues. Advance raising of milking cows was developed by using reduction heat stress methods. Tilapia are raised in open ponds and greenhouse ponds, and ostriches adapted to desert conditions were introduced. On the southern Judean hills where precipitation is 250 mm, through soil conservation and rain harvesting, significant afforestation is changing the desert scenery. The human factor on this process such as farmers, agricultural extension agents and research scientists is the leading factor.  相似文献   

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