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本文探讨了汽车夜间行驶中对向会车时,大灯远光产生的灯光对驾驶员视线的影响,并且基于该问题研究了大灯远近光自动切换的方案。 相似文献
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A box model has been implemented to understand the large-scale biogeochemical cycles of nitrogen, phosphorus, and silicon in the Gulf of Riga. The large data sets collected within the international Gulf of Riga Project in 1993/1995 were used to validate the model. The comparison to data was useful in scaling up to the gulf-wide level and scrutinizing the conclusions based on short-term field surveys and experimental studies. The simulations indicate that the limiting role was passing from silicon to phosphorus to nitrogen over the seasons of organic production. However, on an annual scale, nutrient limitation was close to the “Redfield equilibrium”. Mass balance considerations, based on modeled coupled fluxes, disagree with the conclusions on low sediment denitrification and high phosphorus retention in the pelagic system, which were derived from isolated measurements.Nutrient budgets constructed with the model revealed the high buffer capacity of the Gulf of Riga. The nutrient residence times span a range from 6 years for N to 70 years for Si. The buffering arises from intensive internal recycling in the water body and by the bottom sediments. The budgets indicate that the Gulf retains about two-thirds of external nitrogen and silicon inputs, while phosphorus retention is only 10%.A slow response to external perturbations is demonstrated with numerical experiments run for 15 years under 50% reductions of terrestrial nutrient inputs. These experiments imply that the most effective is the N+P reduction scenario, which resulted in a 20% decrease of primary production after 12 years. A reduction of P resulted in only a 6% decrease of primary production; however, it yielded an 80% drop in the amount of nitrogen fixation. 相似文献
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驾驶疲劳表现特征是多维度、多侧面。本文重点研究驾驶疲劳的致因因素及其交互作用;驾驶疲劳的形成过程、规律及机理;驾驶疲劳失衡性测试与评价,驾驶疲劳馈选模式,驾驶疲劳效应分析;驾驶疲劳综合评价体系。主要研究内容如下:1 多角度、深层次地研究驾驶行为,进而分析导致驾驶疲劳的各种直接、间接因素,建立了诸因素单独作用及相互作用的数学模型。2 研究驾驶疲劳形成过程,采用传递函数将其量化、简约化、模式化,依据自控理论将驾驶疲劳模型化为惯性环节及比例微分环节的合成。所建模型表明驾驶疲劳具有二阶系统的一般特性。3 对多种疲劳… 相似文献
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The first field experiment with intelligent speed adaptation (ISA) in Malaysia was held in December 2010 in the State of Penang. Eleven private cars were instrumented with an advisory system. The system used in the present study included a vocal warning message and a visual text message that is activated when the driver attempts to exceed the speed limit. When the driver decreases the speed, the warning stops; otherwise it is continuously repeated. The test drivers drove the vehicles for three months with the installed system, and the speed was continuously logged in all vehicles. The warning was however only activated in the second month of the three month period. The present study aimed to evaluate the effects of an advisory ISA on driving speed, traffic safety, and drivers' attitude, behavior, and acceptance of the system. To examine these effects, both the survey and the logged speed data were analyzed and explored. The results show a significant reduction in the mean, maximum and 85th percentile speed due to the use of the system. However, there was no long-lasting effect on the speed when the system was deactivated. In the post-trial survey, drivers declared that the system helped them well in following the speed limits and that it assisted them in driving more comfortably. Furthermore, the warning method was more accepted compared to a supportive system, such as active accelerator pedal (AAP). After the trial, most drivers were willing to keep an ISA system. 相似文献
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In many countries two-lane rural highways constitute a large proportion of the road network. One of the most fatal crash types is head-on collisions. Some of these head-on collisions are caused by failed passing maneuvers, when a driver does not succeed to complete the pass safely. 相似文献
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