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511.
Objective: Drivers’ use of lane departure warning and prevention systems is lower than use of other crash avoidance technologies and varies significantly by manufacturer. One factor that may affect use is how well a system prevents unintended departures. The current study evaluated the performance of systems that assist in preventing departures by providing steering or braking input in a 2016 Chevrolet Malibu, 2016 Ford Fusion, 2016 Honda Accord, and 2018 Volvo S90. These vehicles were selected because a prior observational study found that the percentage of privately owned vehicles that had lane departure prevention systems turned on varied among these 4 automakers.Method: In each vehicle, a test driver induced 40 lane drifts on left and right curves by steering the vehicle straight into the curve so that vehicles departed in the opposite direction and 40 lane drifts on straightaways by slight steering input to direct the vehicle to left and right lane markers.Results: Vehicles from automakers with higher observed lane departure prevention use rates (Volvo, Chevrolet) featured systems that provided steering input earlier and more often avoided crossing lane markers by more than 35?cm compared to vehicles from automakers with lower observed use rates (Ford, Honda).Conclusion: The study identified functional characteristics (i.e., timing of steering input, prevention of departures more than 35?cm) of lane departure prevention systems that were strongly associated with observed activation of these systems in privately owned vehicles. Although this relationship does not imply causation, the findings support the hypothesis that functional characteristics of lane departure prevention systems affect their use. Designers may be able to use these results to maximize driver acceptance of future implementations of lane departure prevention. 相似文献
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Heinrich Sandermann Jr. 《Die Naturwissenschaften》1987,74(12):573-578
The plant metabolism of pesticides typically leads to various classes of persistent "soluble" and "insoluble" conjugates whose structures and modes of formation and storage have been characterized only in recent years. Pesticide risk assessment should include studies on animal bioavailability and toxicological properties of the conjugates. 相似文献
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自然保护区、恢复力和动态景观 总被引:18,自引:0,他引:18
Carl Folke Margareta Ihse Fredrik Moberg Magnus Nystrm Janne Bengtsson Per Angelstam Thomas Elmqvist Urban Emanuelsson 《Ambio-人类环境杂志》2003,32(6):389-396
在这个日益被人类活动所改变的世界里,保护生物多样性对于维持有恢复力的生态系统和确保生态系统产品的可持续流动以及对社会的服务是至关重要的.但是,现有的自然保护区和国家公园不大可能结合生态系统的长期和大尺度的动态.因此,保护策略必须包括大面积的人类利用经营的土地.为了能使生态系统在大规模的自然和人为干扰之后得以重组,以生态存储形式出现的空间恢复力是必备的前提.生态存储包括那些能使生态系统得以重组的物种、相互作用和结构,它的组成部分可能出现在干扰斑块中,也可能出现在周围的景观中.现有的静态自然保护区应该由动态自然保护区加以补充,例如生态休闲地和动态演替保护区,这些都是在景观尺度上模拟自然干扰状况,进行生态系统经营的组成部分. 相似文献
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Identification of sex pheromone components of the pea midge, Contarinia pisi (Diptera: Cecidomyiidae) 总被引:1,自引:0,他引:1
Ylva Hillbur Peter Anderson Heinrich Arn Marie Bengtsson Jan Löfqvist Anthony J. Biddle Olof Smitt Hans-Erik Högberg Ernst Plass Stephan Franke Wittko Francke 《Die Naturwissenschaften》1999,86(6):292-294
Three components in extract of pheromone glands of female pea midges, Contarinia pisi, were found to be active on male pea midge antennae by coupled gas chromatographic-electroantennographic detection. The EAD
active components were identified as 2-acetoxytridecane, (2S,11S)-diacetoxytridecane, and (2S,12S)-diacetoxytridecane. A blend of these compounds proved to be highly attractive to males in windtunnel experiments.
Received: 12 November 1998 / Accepted in revised form: 26 january 1999 相似文献
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