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141.
Abstract

Objective: The objective of this research study was to estimate the number of left turn across path/opposite direction (LTAP/OD) crashes and injuries that could be prevented in the United States if vehicles were equipped with an intersection advanced driver assistance system (I-ADAS).

Methods: This study reconstructed 501 vehicle-to-vehicle LTAP/OD crashes in the United States that were investigated in the NHTSA National Motor Vehicle Crash Causation Survey (NMVCCS). The performance of 30 different I-ADAS system variations was evaluated for each crash. These variations were the combinations of 5 time-to-collision (TTC) activation thresholds, 3 latency times, and 2 different response types (automated braking and driver warning). In addition, 2 sightline assumptions were modeled for each crash: One where the turning vehicle was visible long before the intersection and one where the turning vehicle was only visible within the intersection. For resimulated crashes that were not avoided by I-ADAS, a new crash delta-V was computed for each vehicle. The probability of Abbreviated Injury Scale 2 or higher injury in any body region (Maximum Abbreviated Injury Scale [MAIS] 2+F) to each front-row occupant was computed.

Results: Depending on the system design, sightline assumption, I-ADAS variation, and fleet penetration, an I-ADAS system that automatically applies emergency braking could avoid 18–84% of all LTAP/OD crashes. Only 0–32% of all LTAP/OD crashes could have been avoided using an I-ADAS system that only warns the driver. An I-ADAS system that applies emergency braking could prevent 47–93% of front-row occupants from receiving MAIS 2?+?F injuries. A system that warns the driver in LTAP/OD crashes was able to prevent 0–37% of front-row occupants from receiving MAIS 2?+?F injuries. The effectiveness of I-ADAS in reducing crashes and number of injured persons was higher when both vehicles were equipped with I-ADAS.

Conclusions: This study presents the simulated effectiveness of a hypothetical intersection active safety system on real crashes that occurred in the United States. This work shows that there is a strong potential to reduce crashes and injuries in the United States.  相似文献   
142.
A number of different approaches have been used to explain the successes and failures of biodiversity conservation strategies in developing countries. However, to date, little attention has been paid toward assessing the influence of knowledge transfer between science, policy, and conservation practices in the implementation of these strategies. Vietnam’s Pu Luong Cuc Phuong Conservation Area is a globally important ecosystem, situated within a limestone landscape and inhabited by hundreds of local communities. Biodiversity conservation has become an important part of sustainable development in this area. This study analyzes three conservation strategies employed in the Pu Luong Cuc Phuong Conservation Area by applying the Research–Integration–Utilization (RIU) model of scientific knowledge transfer. Our analyses reveal weaknesses in scientific knowledge transfer arising from low-quality research and poor integration strategies. Based on our results, we developed recommendations to improve research and integration in an effort to enhance science-based policy support.  相似文献   
143.
The Caribbean is highly vulnerable to coastal hazards. Based on their short recurrence intervals over the intra-American seas, high-category tropical cyclones and their associated effects of elevated storm surge, heavy wave impacts, mudslides and floods represent the most serious threat. Given the abundance of historical accounts and trigger mechanisms (strike-slip motion and oblique collision at the northern and southern Caribbean plate boundaries, submarine and coastal landslides, volcanism), tsunamis must be considered as well. This paper presents interdisciplinary multi-proxy investigations of sediment cores (grain size distribution, carbonate content, loss-on-ignition, magnetic susceptibility, microfauna, macrofauna) from Washington-Slagbaai National Park, NW Bonaire (Leeward Antilles). No historical tsunami is recorded for this island. However, an allochthonous marine layer found in all cores at Boka Bartol reveals several sedimentary criteria typically linked with tsunami deposits. Calibrated 14C data from these cores point to a palaeotsunami with a maximum age of 3,300 years. Alternative explanations for the creation of this layer, such as inland flooding during tropical cyclones, cannot entirely be ruled out, though in recent times even the strongest of these events on Bonaire did not deposit significant amounts of sediment onshore. The setting of Boka Bartol changed from an open mangrove-fringed embayment into a poly- to hyperhaline lagoon due to the establishment or closure of a barrier of coral rubble during or subsequent to the inferred event. The timing of the event is supported by further sedimentary evidence from other lagoonal and alluvial archives on Bonaire.  相似文献   
144.
Constraints on global fire activity vary across a resource gradient   总被引:4,自引:0,他引:4  
Krawchuk MA  Moritz MA 《Ecology》2011,92(1):121-132
We provide an empirical, global test of the varying constraints hypothesis, which predicts systematic heterogeneity in the relative importance of biomass resources to burn and atmospheric conditions suitable to burning (weather/climate) across a spatial gradient of long-term resource availability. Analyses were based on relationships between monthly global wildfire activity, soil moisture, and mid-tropospheric circulation data from 2001 to 2007, synthesized across a gradient of long-term averages in resources (net primary productivity), annual temperature, and terrestrial biome. We demonstrate support for the varying constraints hypothesis, showing that, while key biophysical factors must coincide for wildfires to occur, the relative influence of resources to burn and moisture/weather conditions on fire activity shows predictable spatial patterns. In areas where resources are always available for burning during the fire season, such as subtropical/tropical biomes with mid-high annual long-term net primary productivity, fuel moisture conditions exert their strongest constraint on fire activity. In areas where resources are more limiting or variable, such as deserts, xeric shrublands, or grasslands/savannas, fuel moisture has a diminished constraint on wildfire, and metrics indicating availability of burnable fuels produced during the antecedent wet growing seasons reflect a more pronounced constraint on wildfire. This macro-scaled evidence for spatially varying constraints provides a synthesis with studies performed at local and regional scales, enhances our understanding of fire as a global process, and indicates how sensitivity to future changes in temperature and precipitation may differ across the world.  相似文献   
145.
Summary This, The First World Conservation Lecture, was presented at the Royal Institution, London, UK, on 12 March 1981. The Lecture celebrated the 20th anniversary of the World Wildlife Fund, and the first anniversary of the World Conservation Strategy. The Lecture was organized by the World Wildlife Fund, UK.Published with the kind permission of the World Wildlife Fund, UK.Edward Max Nicholson, CB, CVO, Commandeur (Netherlands), Order of the Golden Ark, holds honorary doctorates from the University of Aberdeen, and The Royal College of Art London. He was educated at the University of Oxford, and was a member of the University's expeditions to Greenland (1928) and to British Guiana (1929). He was General Secretary (until 1940), later Chairman of PEP (Political and Economic Planning): now Vice-President of its successor body, the Policy Studies Institute. From 1945 to 1952 he was Secretary of the Office of the Lord President of the Council, then Deputy Prime Minister of the United Kingdom. He was member of the Advisory Council on Scientific Policy from 1948–1964. In 1952 he was leader of the joint UN/FAO Development Team in Baluchistan. Charter Member from 1949, and Director-General (1952–1966) of the Nature Conservancy, London, UK. From 1963 to 1974 he was Convenor of the Conservation Section of the International Council of Scientific Unions' International Biological Programme. President of the IUCN Technical Meeting in Edinburgh in 1956, concerned with rehabilitation of areas biologically devastated by human disturbance, and relation of ecology to landscape planning. Member, Panel on Landscape Action Program, The White House Conference (USA) on Natural Beauty (1965). Secretary, HRH The Duke of Edinburgh's Study Conference on The Countryside in 1970 (1963 and 1965). Council and Board Member of IIED. Godman-Salvin Medallist British Ornithologist Unions. Phillips Medallist and Member of Honour IUCN, Geoffroy St. Hilaire Gold Medal, Société Nationale de Protection de Nature de France, Premio Europeo Cortina-Ulisse (1971), Europa Preis für Landespflege (1972), Hon Member of World Wildlife Fund, Chairman Ecological Parks Trust, President RSPB, 1980. Principal Consultant and Chairman of Land Use Consultants Ltd (London) since 1966. Author of many books,Birds and Men (1951);Britain's Nature Reserves (1958),The System (1967);The Environmental Revolution (1970).  相似文献   
146.
147.
Crystalline NiS and CoS particles have considerably greater toxic and cell transforming activity than amorphous NiS and CoS particles. These differences in biological activities were attributable to the active phagocytosis of crystalline metal sulfides particles compared with low uptake of amorphous particles. An examination of the surface of crystalline and amorphous metal sulfide particles revealed that cry-stalline NiS and CoS have a net negative surface charge while the surface charge of the amorphous derivatives appears to be positive. Additionally, chemical reduction of NiS particles with LiAlH4 enhanced their entry into cells. X-ray photoelectron spectroscopy analysis of amorphous and crystalline NiS showed that the outermost surface of the two compounds (1–4 nanometers) differed with respect to the Ni/S ratio and the sulfur oxidation state.  相似文献   
148.
149.
Stephenson M 《Disasters》2005,29(4):337-350
Effective coordination of humanitarian assistance activities remains elusive. This paper briefly addresses some of the reasons for what is widely perceived as a coordination dilemma in humanitarian affairs and argues for a new conceptualisation of the issue. Rather than continue to request that more authority be vested in a single organisation to secure coordination through top-down control, it contends that it may be timely to consider whether relief agencies involved in an emergency should be reconceived as social networks and efforts made to achieve changes in their organizational cultures that encourage operational coordination across institutional lines. Since such labours imply the need to trust, this article explores what forms of trust might be employed to promote improved coordination among relief institutions and how those relationships could themselves be conceptualised. Finally, while acknowledging that coordination is not costless, it suggests that its effective pursuit may be advantageous even in scenarios where aid organisations balk at cooperating to secure it.  相似文献   
150.
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