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71.
驾驶员感知特性对隧道群交通安全的影响 总被引:1,自引:1,他引:0
针对高速公路隧道群对驾驶员感知特性的影响,以驾驶员的感知特性与高速公路隧道群行车安全的关系为研究对象,采用速度估计测试仪和深度知觉测试仪,在"铜汤高速-安徽段"沿线对高速公路隧道群行车途中的160名驾驶员进行实地测试,所得数据进行t检验和方差分析,用灰色建模软件V2.1进行关联度分析。结果表明:驾驶员的速度估计特性与高速公路隧道群驾驶员的年龄、驾龄以及连续行车时间具有较强的相关性,其中连续驾车时间的影响最大。年龄对驾驶员深度知觉准确性无显著影响;驾龄、连续行车时间对驾驶员的深视力准确性有显著影响。 相似文献
72.
豫东黄河故道湿地鸟类自然保护区现状调查及生态保护规划 总被引:4,自引:0,他引:4
对豫东黄河故道湿地鸟类自然保护区现状进行了调查,并提出了生态保护规划。 相似文献
73.
How and when migrants integrate directional information from different sources may depend not only on the bird’s internal
state, including fat stores, but also on the ecological context during passage. We designed experiments to (1) examine the
influence of stored fat on the decision to migrate and on the choice of migratory direction and (2) investigate how the integration
of orientation cue information is tied to energetic status in relation to migration across an ecological barrier. Migratory
orientation of red-eyed vireos (Vireo olivaceus) at twilight was recorded using two different techniques, orientation cage experiments and free-flight release tests, during
both fall and spring migration. During fall migration, the amount of stored fat proved decisive for directional selections
of the vireos. Fat birds chose directions in accordance with migration across the Gulf of Mexico. Lean birds oriented either
parallel to the coast line (cage tests) or moved inland (free-flight releases). Whereas only fat birds showed significant
responses to experimental deflections of the geomagnetic field, lean birds displayed a tendency to shift their activity in
the expected direction, making it difficult to evaluate the prediction that use of the magnetic compass is context dependent.
Fat loads also had a significant effect on the decision to migrate, i.e., fat individuals were more likely to embark on migration
than were lean birds (true for both cage and release experiments). During spring migration, a majority of experimental subjects
were classified as lean, following their arrival after crossing the Gulf of Mexico, and oriented in seasonally appropriate
directions. The vireos also showed significant responses to experimental deflections of the geomagnetic field regardless of
their energetic status. Free-flight release experiments during spring migration revealed a significant difference in mean
directions between clear sky and overcast tests. The difference may indicate a compensatory response to wind drift or possibly
a need for celestial cues to calibrate the magnetic compass. Finally, this is the first demonstration of magnetic compass
orientation in a North American vireo.
Received: 15 December 1995/Accepted after revision: 24 March 1996 相似文献
74.
Dennis D. Mwanza 《Environment, Development and Sustainability》2003,5(1-2):95-115
Water is a precious yet non-renewable resource. Yet in Africa, the same water can be a source of life and death. Water is not only the most basic of need but also at the centre of sustainable development and essential for poverty eradication. Water is intimately linked to health, agriculture, energy and biodiversity. Without progress on water, reaching other Millennium Development Goals (MDGs) will be difficult if not impossible. The fight against poverty will remain a pipe dream.A lot of activities have been undertaken with the aim of highlighting the importance of water, linking water with sustainable development and indeed developing strategies for resolving the ever-increasing problems of water. These include the adoption of the Africa Water Vision in The Hague, Netherlands in March, 2000.In order to address the many problems of water in Africa especially related to the coordination of the increasing number of initiatives in the Water sector in Africa, the African Water Task Force (AWTF) was established.As part of developing solutions to the African water crisis, the AWTF held a regional conference in Accra Ghana. Some of the emerging issues from the Accra Conference are highlighted in the Accra declaration.This paper highlights the linkages between water and sustainable development, water and poverty and the many facets that relate to water. It mainly addresses issues of water from the African perspective. A number of key events that have taken place and which have served as a basis for many policy pronouncements have been given.The last section concentrates on what happened to water at the World Summit for Sustainable Development (WSSD) held in Johannesburg in September 2002. 相似文献
75.
澳大利亚职业眼睛健康管理 总被引:1,自引:0,他引:1
郭德华 《中国个体防护装备》2012,(3):41-45
在由于从事具有眼睛伤害风险工作而导致的职业眼睛健康问题之外,随着新兴技术的发展,工作场所电子设备的长时间使用也会导致电脑视觉综合症(CVS)等职业眼睛健康问题。本文主要介绍了澳大利亚职业眼睛健康管理的方法,包括职业眼睛健康风险、单位与职工的职责、预防措施等.以对我国职业眼睛健康风险进行有效管理提供帮助。 相似文献
76.
Tuomas Väisänen Vuokko Heikinheimo Tuomo Hiippala Tuuli Toivonen 《Conservation biology》2021,35(2):424-436
Understanding the activities and preferences of visitors is crucial for managing protected areas and planning conservation strategies. Conservation culturomics promotes the use of user-generated online content in conservation science. Geotagged social media content is a unique source of in situ information on human presence and activities in nature. Photographs posted on social media platforms are a promising source of information, but analyzing large volumes of photographs manually remains laborious. We examined the application of state-of-the-art computer-vision methods to studying human–nature interactions. We used semantic clustering, scene classification, and object detection to automatically analyze photographs taken in Finnish national parks by domestic and international visitors. Our results showed that human–nature interactions can be extracted from user-generated photographs with computer vision. The different methods complemented each other by revealing broad visual themes related to level of the data set, landscape photogeneity, and human activities. Geotagged photographs revealed distinct regional profiles for national parks (e.g., preferences in landscapes and activities), which are potentially useful in park management. Photographic content differed between domestic and international visitors, which indicates differences in activities and preferences. Information extracted automatically from photographs can help identify preferences among diverse visitor groups, which can be used to create profiles of national parks for conservation marketing and to support conservation strategies that rely on public acceptance. The application of computer-vision methods to automatic content analysis of photographs should be explored further in conservation culturomics, particularly in combination with rich metadata available on social media platforms. 相似文献
77.
Many animal signals are performed in a highly redundant manner as in some bird species where males sing several renditions of one song type before switching to another. However, differences in signal redundancy between contexts and between individuals are only poorly understood. We found that chaffinches (Fringilla coelebs) in noisier areas (i.e., close to waterfalls and torrents) sang longer bouts of the same song type before switching to a new type, suggesting that they use increased serial redundancy to get the message across in noisy conditions. This is the first evidence of a noise-dependent adjustment of signal redundancy in a songbird. In addition, we found that song types with faster trills were sung in shorter bouts suggesting that the performance of highly redundant song series is probably limited by motor constraints. Thus, in noisy environments, serial redundancy in bird song may reflect a trade-off between successful signal transmission and preventing motor fatigue. 相似文献
78.
针对石油石化企业HSSE管理体系运行中存在的问题,基于企业实际情况,采用系统方法设计提出了石油石化企业HSSE管理体系运行模式。从企业整体角度,运用战略思维提出HSSE管理体系运行的推进模型和方法,从战略、组织、能力、信息、流程、绩效6个方面,提出HSSE管理体系运行要求。通过创新HSSE管理体系运行模式和推进方法,企业能够从更加宏观的角度,整合有限资源实现HSSE管理体系有效运行,从而提升企业HSSE绩效。 相似文献
79.
基于多信息检测的车辆智能防撞预警技术研究 总被引:3,自引:2,他引:1
运用多源信息检测技术对驾驶状态进行综合检测,利用架设在车辆外部的摄像机获取本车与前方车辆之间的相对距离、相对速度信息,利用架设在车辆内部的摄像机获取驾驶人状态信息,通过综合判断降低车辆防撞检测的漏警率、误警率以及冗余报警率;构建车辆行驶安全判定规则,对行车实时危险和潜在危险进行检测、分析与判断,获取可靠的防撞警示提醒;使反应时间、相对距离、相对速度3个方面都能得到优化控制,从而避免车辆碰撞事故;同时也为提高车速、增加道路通行能力、实现自动驾驶等奠定良好的基础。 相似文献
80.
Food restrictions early in life can have adverse effects on the development of adult avian song structure. Nutritional deficiencies
during brain development are thought to impair the growth of neural circuits responsible for learning and production of song
in adulthood. Thus, the quality of song may reflect the quality of the singer due to the costs associated with neural development
early in life. Recent investigations have focused on domesticated laboratory strains of zebra finches where early dietary
deficiencies have significantly reduced the complexity of song and its sexual attractiveness. Domesticated zebra finches may
be more sensitive to the early effects of moderate under-nutrition on song complexity than their non-domesticated counterparts.
In an aviary experiment with non-domesticated zebra finch stock, we found that song complexity when measured by a linear combination
of six variables was reduced in food-restricted birds, with syllable rate and maximum syllable frequency as the principal
variables affected. The restriction had no effect on learning accuracy when song phrases of experimental birds were compared
to those of their fathers.This result demonstrates that early nutrition may differentially affect the development of neural
processes that influence learning accuracy and song complexity. While the finding of negative effects of dietary restriction
on song complexity is robust for zebra finches and is not an artefact of domestication, it does not explain why some nutritionally
stressed populations of wild zebra finches have more complex songs than those from other regions of Australia characterised
by greater food availability. 相似文献