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81.
82.
People with seafaring experience and skills are employed in the maritime sector of the UK economy in land-based jobs as well as in seagoing ones. This paper examines the balance of supply and demand in the land-based jobs market. It then considers the likely effects of a shortfall in the supply of British ships’ officers to fill net vacancies in jobs ashore, including the policy implications of this and the consequences for the economy's maritime skills base if the Government fails to act decisively now to correct market failure. 相似文献
83.
James D. Eynard Bernhard Jenny 《International journal of geographical information science》2016,30(10):1923-1943
Shadowed contour lines vary line width. Illuminated contour lines additionally vary color based on an angle of illumination. Illuminated and shadowed contour lines date back to the mid-nineteenth century, but their effectiveness compared to conventional contour lines has not been fully examined. Currently, illuminated and shadowed contour lines are not widely used in computer-based cartography because they are not included in most GIS apmaking software. This article introduces improvements to existing algorithms for creating illuminated and shadowed contour lines from digital elevation data. A software package is made available to allow mapmakers to more easily make customized illuminated and shadowed contour maps. A user study comparing illuminated and shadowed contour lines to conventional contour lines and shaded relief with approximately 400 participants was conducted. Results indicate that map-readers can interpret relative height differences between points better and quicker with illuminated contour lines than regular contour lines or shaded relief. Study participants were able to select absolute maxima on an unlabeled illuminated contour map and a labeled regular contour map with equal accuracy and speed. These findings suggest that illuminated contour lines could be used more frequently for improved visualization of terrain and other surface data on maps. 相似文献
84.
85.
Graciano P. Yumul JR Carla B. Dimalanta Rodolfo A. Tamayo JR Jenny Anne L. Barretto 《Island Arc》2000,9(4):627-637
Abstract The Palawan microcontinental block collided with the Philippine Mobile Belt in the Central Philippine region resulting in the counterclockwise rotation of Mindoro– Marinduque and clockwise rotation of Panay. The collision also brought about the clockwise rotation of north-east Negros, Cebu, north-west Masbate and Bohol (collectively called the Western Visayan block), resulting into their present-day northeast–southwest trend. This suggests a far more dramatic role of the collision than was previously recognized. Furthermore, the south-east Sulu Sea sub-basin is inferred to have also undergone collision-related clockwise rotation which can account for the observed east-west trending magnetic lineations in the basin. Aside from explaining the contrasting morphological trends of the different islands in Central Philippines, the rotation can also explain, albeit in a different way, how the belts of sedimentary basins, ophiolites and arcs in Panay and Negros can extend to Northern Luzon. Published paleomagnetic data suggest that the collision-related rotation commenced during the early to middle Miocene and had ceased by the late Miocene. 相似文献
86.
The Global Earthquake Vulnerability Estimation System (GEVES): an approach for earthquake risk assessment for insurance applications 总被引:4,自引:0,他引:4
Robin Spence Emily So Sarah Jenny Hervé Castella Michael Ewald Edmund Booth 《Bulletin of Earthquake Engineering》2008,6(3):463-483
For the insurance and reinsurance industries, earthquake loss estimation is crucial not only to adequately price its product
but also to manage the accumulation risk in the face of the ever-increasing exposure in highly seismic regions. Changes in
the built environment and a continuously evolving earthquake science make it a necessity for the industry to constantly refine
earthquake loss estimation models. In particular, it has been recognized for a long time that the vulnerability of buildings
to ground shaking is a key parameter in any earthquake risk model. Current methods tend either to rely on the limited historical
damage and loss data or on the numerical simulation of the response of individual buildings to the ground-shaking produced
by earthquakes. Although both methods have their advantages and pitfalls, we are proposing here a simple solution, using transparent
input data, that can be realistically used for the needs of the insurance and reinsurance industry, whether detailed information
about the insured structures is available or not. The resulting product is known as GEVES (Global Earthquake Vulnerability
Estimation System). It is primarily intended for evaluating the mean damage ratio (MDR) suffered by a portfolio of buildings
classified by use, under the action of a given earthquake scenario (i.e. an earthquake of given size at a given distance from
the portfolio of buildings). A key assumption was that macroseismic intensity rather than spectral displacement would be the
basis of loss estimation. The paper describes the model with emphasis on its structure and the justification for the assumptions
made. In addition to a new set of earthquake vulnerability functions, the paper also provides recommendations on some aspects
of the earthquake hazard, in particular about how to define macroseismic intensity at the site of interest, for a given earthquake
scenario. This paper also discusses validation of the GEVES model against calculated vulnerability approaches, and the treatment
of uncertainty within the model. 相似文献
87.
88.
The depiction of pristine countryside in New Zealand film has engendered a cultural disconnection with the environmental stories within the landscape. In this essay, we briefly examined the meaning of rural New Zealand landscape and its role in film. This research was done in part by making a short documentary, River Dog, a film about the rural New Zealand landscape. The character, plot and underlying message of River Dog were framed within visually relevant archetypes to form a constructive environmental message. Here, we examined River Dog's use of empathetic storytelling, an approach used to communicate an environmental issue without promulgating science or politics. 相似文献
89.
Jenny Moehler K. Mathias Wegner Karsten Reise Sabine Jacobsen 《Journal of Sea Research》2011,66(3):256-262
As a result of aquaculture activities Pacific oysters Crassostrea gigas (Thunberg, 1793) have invaded the European Wadden Sea. Using a variable noncoding mitochondrial marker, we show that the invaded range is the result of two independent invasions. Haplotype frequencies point towards two separate groups, one in the southern and the other in the northern Wadden Sea. We found virtually no genetic differentiation throughout the southern range and the putative source from British Columbia, Canada, suggesting that the Southern region can be considered as a closed population. In the North, mismatch distributions, haplotype ordination and isolation-by-distance analysis suggest a stronger, persistent impact of aquaculture on invasive populations. Due to the ongoing supply of new genetic material from hatchery production the northern invasive populations can therefore be considered as an open population highlighting the importance of aquaculture practice on the genetics of this keystone invader in the Wadden Sea. 相似文献
90.
Hammerschmidt Sebastian B Wiersberg Thomas Heuer Verena B Wendt Jenny Erzinger Jörg Kopf Achim 《Geochemical transactions》2014,15(1):1-9