The use of flying robots (drones) is increasing rapidly, but their utility is limited by high power demand, low specific energy storage and poor gust tolerance. By contrast, birds demonstrate long ...endurance, harvesting atmospheric energy in environments ranging from cluttered cityscapes to open landscapes, coasts and oceans. Here, we identify new opportunities for flying robots, drawing upon the soaring flight of birds. We evaluate mechanical energy transfer in soaring from first principles and review soaring strategies encompassing the use of updrafts (thermal or orographic) and wind gradients (spatial or temporal). We examine the extent to which state-of-the-art flying robots currently use each strategy and identify several untapped opportunities including slope soaring over built environments, thermal soaring over oceans and opportunistic gust soaring. In principle, the energetic benefits of soaring are accessible to flying robots of all kinds, given atmospherically aware sensor systems, guidance strategies and gust tolerance. Hence, while there is clear scope for specialist robots that soar like albatrosses, or which use persistent thermals like vultures, the greatest untapped potential may lie in non-specialist vehicles that make flexible use of atmospheric energy through path planning and flight control, as demonstrated by generalist flyers such as gulls, kites and crows.
In order to compensate for the low partial pressure of oxygen at altitude, the human body undergoes a number of physiological changes. A vital component in this process is the increase in the ...concentration of circulating haemoglobin. The role of HIF-1α, erythropoietin and red blood cells in this acclimatisation process is described, together with the fall in plasma volume that increases the concentration of haemoglobin in the early stages of hypoxic exposure.
Understanding risks faced by firms and their reactions in response to those risks requires analysis of the ambiguities inherent in human behaviour. Yet, evidence from two case studies on investment ...and insurance professionals in the finance industry suggests that more focus on human capital may be prudent in reducing epistemic uncertainty particularly considering recent events in which the investing public has had a crisis of confidence in corporate leaders. It is particularly appropriate for regulators to provide a context in which market participants exercise due diligence by ensuring that human capital is enhanced by as much knowledge as possible where more human capital knowledge could reduce both risk in investments and insurance, ultimately challenging the sustainability of organisations during periods of epistemic uncertainty. This paper suggests that investment analysts, fund managers and insurance professionals lack the appropriate competencies, skills, knowledge and abilities required to meet the demands of the analysis of human capital in relation to understanding risk. Such competencies include disciplinary knowledge of sustainable human resource management (HRM) and organisational change systems and their links to corporate performance and risk mitigation. An alignment with HRM/HR that is equally focused on internal and external risk is of strategic importance for such professionals and their organisations in human capital risk mitigation.
The growing popularity of activities such as hiking, climbing, skiing and snowboarding has ensured that the number of visitors to mountain environments continues to increase. Since such areas place ...enormous physical demands on individuals, it is inevitable that deaths will occur. Differences in the activities, conditions and methods of calculation make meaningful mortality rates difficult to obtain. However, it is clear that the mortality rate for some mountain activities is comparable to hang gliding, parachuting, boxing and other pastimes that are traditionally viewed as dangerous. Deaths in the mountains are most commonly due to trauma, high altitude illness, cold injury, avalanche burial and sudden cardiac death. This review describes the mortality rates of those who undertake recreational activities in the mountains and examines the aetiology that lies behind them.
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