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141.
This conceptual model of avalanche hazard identifies the key components of avalanche hazard and structures them into a systematic, consistent workflow for hazard and risk assessments. The method is applicable to all types of avalanche forecasting operations, and the underlying principles can be applied at any scale in space or time. The concept of an avalanche problem is introduced, describing how different types of avalanche problems directly influence the assessment and management of the risk. Four sequential questions are shown to structure the assessment of avalanche hazard, namely: (1) What type of avalanche problem(s) exists? (2) Where are these problems located in the terrain? (3) How likely is it that an avalanche will occur? and (4) How big will the avalanche be? Our objective was to develop an underpinning for qualitative hazard and risk assessments and address this knowledge gap in the avalanche forecasting literature. We used judgmental decomposition to elicit the avalanche forecasting process from forecasters and then described it within a risk-based framework that is consistent with other natural hazards disciplines.  相似文献   
142.
Confusion surrounding the definition and application of terminology in post-mining ecological repair has resulted in uncertainty for industry, the scientific community and regulators. This lack of clarity may underrepresent high aspirations or could be misused to disguise low aspirations and so is problematic for setting objectives, establishing goals and assessing recovery trajectories. We respond to a recently published analysis of the ecosystem repair literature, where we highlight inconsistencies stemming from inadequate reference to a large proportion of the restoration and rehabilitation literature. We outline increasingly well-accepted and internationally applied definitions concerning the restoration and recovery process and invite both the mining industry and policy-makers to re-examine their terminology in the interests of attaining an internationally agreed nomenclature. Clarity in the use and understanding of terminology will align post-mining targets with community expectation, enhance the capacity of the mining industry to understand and meet these targets, and foster better analysis and more industry-relevant discussion of recovery methodologies by the scientific community and practitioners.  相似文献   
143.
A geoprivacy manifesto   总被引:1,自引:0,他引:1       下载免费PDF全文
As location‐enabled technologies are becoming ubiquitous, our location is being shared with an ever‐growing number of external services. Issues revolving around location privacy—or geoprivacy—therefore concern the vast majority of the population, largely without knowing how the underlying technologies work and what can be inferred from an individual's location (especially if recorded over longer periods of time). Research, on the other hand, has largely treated this topic from isolated standpoints, most prominently from the technological and ethical points of view. This article therefore reflects upon the current state of geoprivacy from a broader perspective. It integrates technological, ethical, legal, and educational aspects and clarifies how they interact and shape how we deal with the corresponding technology, both individually and as a society. It does so in the form of a manifesto, consisting of 21 theses that summarize the main arguments made in the article. These theses argue that location information is different from other kinds of personal information and, in combination, show why geoprivacy (and privacy in general) needs to be protected and should not become a mere illusion. The fictional couple of Jane and Tom is used as a running example to illustrate how common it has become to share our location information, and how it can be used—both for good and for worse.  相似文献   
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Fulani herder and farmer relationships in West Africa have always been troublesome as a result of farmers’ fundamental rejection of the herders’ inroads into their areas and also because of increased competition for available resources. In countries such as Ghana, local and even national campaigns have been launched to expel the herders but they persist. This case-study which utilised interviews and group discussions involving farmers and herders, sought to understand the dynamics and subtleties of herders’ resilience in an environment where natural resource access and use rights are tied to common property principles and where herders have no enshrined land and resource rights. Using territoriality as the analytical capsule, we found that the herders’ persistence is related to mainly non-territoriality where the goal is to influence relationships and resource access but not control area. Categorising their non-territorial expression into persuasive and aggressive forms, we provide a new platform for deconstructing farmer-herder relationships in the West African sub-region.  相似文献   
147.
Connectivity between the western and eastern limbs of the Bushveld Complex   总被引:1,自引:0,他引:1  
The mafic layered rocks of the Bushveld Complex are 6–8 km thick and crop out over an area of 65,000 km2. Previous interpretations of the Bouguer gravity anomalies suggested that the intrusion consisted of two totally separate bodies. However, the mafic sequences in these arcuate western and eastern limbs are remarkably similar, with at least six petrologically distinctive layers and sequences being recognisable in both limbs. Such similarity of sequences in two totally discrete bodies 200–300 km apart is petrologically implausible, and it is suggested that they formed within a single lopolithic intrusion.

All previous Bouguer gravity models failed to consider the isostatic response of the crust to emplacement of this huge mass of mafic magma. Isostatic adjustment as a result of this intrusion would have caused the base of the crust to be depressed by as much as 6 km. With this revised whole crustal model, it becomes possible to construct a gravity model, consistent with observed data, which includes a 6 km-thick sequence of mafic rocks connecting the western and eastern limbs of the Bushveld Complex. The exact depth at which the mafic rocks of the Bushveld Complex lie in the centre of the structure cannot be constrained by the gravity data.

Such a first-order model is an approximation, because there have been subsequent deformation and structural readjustments in the crust, some of them probably related to the emplacement of the Bushveld Complex. Specifically, the observed geometry of the rocks around the Crocodile River, Dennilton, Marble Hall and Malope Domes suggests that major upwarping of the crust occurred on a variety of scales, triggered by emplacement of the Bushveld Complex.  相似文献   

148.
Very little existing literature has addressed the issues of the perceived usefulness of 3D visualizations over 2D and the use of cartographic shadow representations in the planning community. Urban planning has moved toward a 3D, geographic-information-system-centric, and functional decision support framework. This study aims to examine the preferences of urban planning professionals with respect to 2D and 3D visualizations in a case study. The authors built a 3D representation of a proposed building along with the existing urban environment in Queenstown, New Zealand and conducted a usefulness test through a survey and interview. Based on the survey, the study evaluated the degree of task utility perceived in each visualization method, the effect on the mental image, and shadow representation preferences. The findings support the literature that the benefits of using a 2D or 3D model are closely related to the types of planning tasks undertaken. The findings also reveal a complex view of planning activities, suggesting that planners themselves cannot be treated as a single group for research purposes.  相似文献   
149.
This paper describes the observations made by a reconnaissance team following the 22nd February 2011, Mw 6.3, Christchurch, New Zealand earthquake (GNS Science, 2011). The team comprised of members of the UK based Earthquake Engineering Field Investigation Team who spent 5 days collecting observations on damage resulting from the earthquake. Although the magnitude of this earthquake was not particularly high (Mw 6.3), the shallow focus and close proximity resulted in locally very high ground motions, widespread damage and 182 fatalities. The earthquake is also particularly notable for the widespread liquefaction it caused, landslides and rockfalls in the hills south of Christchurch, and the significant damage suffered by unreinforced masonry and historic structures. Over wide areas of central Christchurch, recorded accelerations were in excess of those required by the current New Zealand seismic loadings standard (NZS1170.5:2004: Standards New Zealand 2004) and therefore the earthquake presented a valuable opportunity to assess performance of modern buildings under code-level ground acceleration.  相似文献   
150.
In the Philippines, a Catholic social movement for local development and broad structural transformation, referred to as Basic Ecclesial Communities, offers a counter‐narrative to state development. Predicated on the power of networked local groups, the Diocese of San Carlos has taken the original concept and rescaled it, operating a variety of social‐action programmes at the diocese level. The focus of this paper is a unique partnership between the diocese and the Armed Forces of the Philippines, which has produced a number of measurable positive changes in under‐serviced areas. We remain uncertain, however, about the extent to which the church is cooperating with, or being co‐opted by, the military as it enters into partnership, and many members of the clergy share our scepticism. In this paper we draw upon Gramsci's concept of passive revolution (1971) as a means to conceptualize both the efforts of the church to reform society from within, and the reaffirmation of the hegemonic discourse that seems inevitable.  相似文献   
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