新版GB/T19056电磁环境适应性要求分析

介绍了GB/T 19056新版本对汽车行驶记录仪电磁环境适应性要求,比较和分析了新旧版本在电磁环境适应性方面的的异同,重点介绍了新版标准中瞬态抗扰性脉冲的波形和参数要求,研究和探讨了标准中对产品电磁环境适应性要求的内涵.     

成都及其周边地区轻型载客汽车行驶里程调查与分析

研究目的是通过实地调查和统计分析及检验确定成都及其周边地区轻型载客汽车的活动水平(用行驶里程表征)及规律,并比较不同地区间的差异。统计表明,成都及周边城市轻型载客汽车的年均行驶里程为1.5~2.0万km/年。其中绵阳和其他城市间的差异比较显著,而其他城市间的差异在绝对值上较小。成都及其周边地区轻型载客汽车年均行驶里程随车龄呈递减趋势,以成都市最为明显,而周边其他地区稍差。结果表明,为提高机动车尾气排放清单的准确度,对城市差异较大的不同地区的轻型载客汽车的行驶里程进行分别调查是必要的。     

我国成功发射第54颗北斗导航卫星5月将完成全球星座部署

正3月9日19时55分,我国在西昌卫星发射中心用长征三号乙运载火箭,成功发射北斗系统第54颗导航卫星。卫星顺利进入预定轨道,后续将进行变轨、在轨测试、试验评估,适时入网提供服务。这是北斗三号第29颗全球组网卫星,同时也是第2颗地球静止轨道卫星。此类卫星在星基增强、短报文通信、精密单点定位等特色服务上发挥关键作用。北斗系统建设先后经历了北斗一号系统、北斗二号系统、北斗三号系统三个阶段。目前北斗一号4颗试验卫星已全部退役,从北斗二号首颗星起算,我国已发射     

新闻资讯

正北斗三号全球卫星导航系统星座部署全面完成6月23日9时43分,我国在西昌卫星发射中心用长征三号乙运载火箭,成功发射北斗系统第五十五颗导航卫星,暨北斗三号最后一颗全球组网卫星,至此北斗三号全球卫星导航系统星座部署比原计划提前半年全面完成。此次发射的卫星属地球静止轨道卫星,经过一系列在轨测试入网后,我国将进行北斗全系统联调联试,在确保系统运行稳定可靠、性能指标优异基础上,择机面向用户提供全天时、全天候、高精度全球定位导航授时服务,以及星基增强、短报文通信、精密单点定位等特色服     

GPS卫星定位技术在河道整治与环境保护方面的应用

结合GPS卫星定位技术在河道整治与环境保护的应用实例,简要介绍了卫星定位技术的工作原理、基准站设置与应用效果。     

莫斯科实行“关闭政策”为净化空气保护环境

长期以来,莫斯科市空气污染问题一直被列为该市重点治理的灾难之一。为了保护大气环境,改进空气质量,莫斯科市政府最近宣布,对一切外来汽车和过路汽车实行『关闭政策』。这一新政策规定,只有在莫斯科市登记的本市汽车可以在市区行驶,外来汽车和过路汽车一律不得进入市区。莫斯科市市区界线为距市中心十五英里以外的外环路。路过莫斯科的来往车辆必须从外环路绕行,不得横穿市区;到莫斯科去的车辆则必须停放在外环路附近,然后换乘莫斯科市的出租车、公共汽车或地铁进入市区。     

浅谈汽车内饰材料挥发成雾性测试

汽车内饰材料中所含挥发性物质的释放是造成车内环境污染最直接的也是最主要的原因。对汽车内饰材料进行挥发性物质测试的重要方法之一就是挥发成雾性测试。本文中,笔者将对汽车内饰材料挥发成雾性测试的测试原理、测试设备、当前业界流行的主要测试方法和相关的标准作一些介绍。     

IEEE协会公布汽车黑匣子通用标准IEEE1616a

极富争议的机动车行驶记录仪终于有了最新的标准,公众关心的隐私泄露的问题也有了解决方案。国际电气与电子工程师协会（IEEE）已经宣布了基于IEEE1616的一项新标准IEEE1616a,第一个机动车辆事故数据记录仪通用标准（MVEDRs）,这种记录仪同在飞机和火车上安装的仪器极为相似。     

汽车电子电器零部件产品通用测试要求解析

汽车电子电器零部件性能在各种环境下的可靠性测试具有通用性,本文简单解析了国内外汽车电子电器零部件产品通用测试要求的差异,对通用测试要求中常见的微小电信号实时监控方案做出了一点探讨.     

汽车用电子控制装置的可靠性保证

1.前言 近些年来,汽车用的各种控制系统的功能日趋复杂化,汽车电子控制化的倾向与日俱增。出现这种情况的背景是:(1)对排出气体、燃料费的规定等更为严格,为了把这些规定与一般行驶的汽车发动机能力相协调,要逐步谋求精密的控制。(2)人们对汽车安全性、舒适性需要提高,在众多的车种上开始采用刹车控制、四轮控制、牵引力控制等等安全     

Prediction and uncertainty source analysis of the spatial and temporal disturbance from off-road vehicular traffic in a complex ecosystem

Vehicle use during military training activities results in soil disturbance and vegetation loss. The capacity of lands to sustain training is a function of the sensitivity of lands to vehicle use and the pattern of land use. The sensitivity of land to vehicle use has been extensively studied. Less well understood are the spatial patterns of vehicle disturbance. Since disturbance from off-road vehicular traffic moving through complex landscapes varies spatially, a spatially explicit nonlinear regression model (disturbance model) was used to predict the pattern of vehicle disturbance across a training facility. An uncertainty analysis of the model predictions assessed the spatial distribution of prediction uncertainty and the contribution of different error sources to that uncertainty.For the most part, this analysis showed that mapping and modeling process errors contributed more than 95% of the total uncertainty of predicted disturbance, while satellite imagery error contributed less than 5% of the uncertainty. When the total uncertainty was larger than a threshold, modeling error contributed 60% to 90% of the prediction uncertainty. Otherwise, mapping error contributed about 10% to 50% of the total uncertainty. These uncertainty sources were further partitioned spatially based on other sources of uncertainties associated with vehicle moment, landscape characterization, satellite imagery, etc.     

Spatial Relations Between Floodplain Environments and Land Use – Land Cover of a Large Lowland Tropical River Valley: Pánuco Basin, México

Large lowland river valleys include a variety of floodplain environments that represent opportunities and constraints for human activities. This study integrates extensive field observations and geomorphic data with analysis of satellite remote sensing data to examine spatial relations between land use/land cover (LULC) and floodplain environments in the lower Pánuco basin of eastern Mexico. The floodplain of the lower Pánuco basin was delineated by combining a digital elevation model with a satellite image of a large flood event. The LULC was classified by combining a hybrid classification strategy with image stratification, applied to 15-m-resolution ASTER data. A geomorphic classification of floodplain environments was performed using a dry-stage image (ASTER data) and a 1993 Landsat image acquired during a large flood event. Accuracy assessment was based on aerial photographs (1:38,000), global positioning satellite ground-truthing, and a Landsat 7ETM⁺ image from 2000, which resulted in an overall accuracy of 82.9% and a KHAT of 79.8% for the LULC classification. The geomorphic classification yielded 83.5% overall accuracy, whereas the KHAT was 81.5%. LULC analysis was performed for the entire floodplain and individually within four valley segments. The analysis indicates that the study area is primarily utilized for grazing and farming. Agriculture is primarily associated with coarse-grained (sandy/silty) natural levee and point bar units close to the river channel, whereas cattle grazing occurs in distal and lower-lying reaches dominated by cohesive fine-grained (clayey) deposits, such as backswamps. In the Pánuco valley, wetlands and lakes occur within backswamp environments, whereas in the Moctezuma segments, wetlands and lakes are associated with relict channels. This study reveals considerable variation in LULC related to spatial differences in floodplain environments and illustrates the importance of considering older anthropogenic influences on the landscape. The research design should be applicable for other large lowland coastal plain river valleys where agriculture is a major component of the floodplain landscape.     

Detection and Classification of Motor Vehicle Noise in a Forested Landscape

Noise emanating from human activity has become a common addition to natural soundscapes and has the potential to harm wildlife and erode human enjoyment of nature. In particular, motor vehicles traveling along roads and trails produce high levels of both chronic and intermittent noise, eliciting varied responses from a wide range of animal species. Anthropogenic noise is especially conspicuous in natural areas where ambient background sound levels are low. In this article, we present an acoustic method to detect and analyze motor vehicle noise. Our approach uses inexpensive consumer products to record sound, sound analysis software to automatically detect sound events within continuous recordings and measure their acoustic properties, and statistical classification methods to categorize sound events. We describe an application of this approach to detect motor vehicle noise on paved, gravel, and natural-surface roads, and off-road vehicle trails in 36 sites distributed throughout a national forest in the Sierra Nevada, CA, USA. These low-cost, unobtrusive methods can be used by scientists and managers to detect anthropogenic noise events for many potential applications, including ecological research, transportation and recreation planning, and natural resource management.     

国内旅游者人口学特征与行为分析——以延边朝鲜族自治州为例

边境型旅游地因其独特的边境自然风貌、浓厚的异族风情在我国丰富的旅游资源中占有重要地位。通过实地考察，根据游客调查问卷数据和二手资料，与海滨型旅游地普陀山、古村落型旅游地西递和宏村、山岳型旅游地泰山进行了对比分析，揭示了延边朝鲜族自治州国内旅游者的人口学特征、旅游行为、旅游效果等，并就促进其旅游业的进一步发展提出了建议。     

女性旅游者行为特征分析及其动机研究——以西递、宏村为例

利用SPSS社科统计软件对2005年西递、宏村调查数据进行交互分析和主成分分析，得出女性旅游者客源地结构特征、人口统计学特征、决策行为模式、出游动机等一般规律，最后比较分析了我国与美国高学历女性出游动机的异同，试图为国内外女性旅游市场开发和营销人员提供有价值的参考。     

DEVELOPMENT OF EARTH SATELLITE TECHNOLOGY FOR THE TELEMETRY OF HYDROLOGIC DATA1

ABSTRACT The use of satellite telemetry is playing a major role in the collection of hydrologic data. Advancing technology and availability of government satellites have permitted many agencies to take advantage of new procedures for acquiring data from automated remote data collection stations. Experiments with Earth satellite technology started in the 1960's and 1970's, with the polar-orbiting National Aeronautics and Space Administration Nimbus and Landsat satellites. Subsequent advancements took place through the development phase to operational systems using the Geostationary Operational Environmental Satellite (GOES) of the National Oceanic and Atmospheric Administration. This satellite system supports more than 2,500 active telemetry sites, of which approximately 1,200 are Geological Survey stream-gaging stations for the collection of hydrologic data. A satellite data collection system is made up of three primary components; a small battery-operated radio, and Earth-orbiting satellite, and an Earth receive and data processing station. The data relay satellites' vast aerial view of the Earth's surface gives satellite telemetry a large advantage over ground-based systems for the collection of real-time hydrologic data for flood warning, reservoir management, irrigation water control, hydropower generation, and the operation of hydrologic stations.     

Cluster analysis of structural stage classes to map wildland fuels in a Madrean ecosystem

Geospatial information technology is changing the nature of fire mapping science and management. Geographic information systems (GIS) and global positioning system technology coupled with remotely sensed data provide powerful tools for mapping, assessing, and understanding the complex spatial phenomena of wildland fuels and fire hazard. The effectiveness of these technologies for fire management still depends on good baseline fuels data since techniques have yet to be developed to directly interrogate understory fuels with remotely sensed data. We couple field data collections with GIS, remote sensing, and hierarchical clustering to characterize and map the variability of wildland fuels within and across vegetation types. One hundred fifty six fuel plots were sampled in eight vegetation types ranging in elevation from 1150 to 2600 m surrounding a Madrean 'sky island' mountain range in the southwestern US. Fuel plots within individual vegetation types were divided into classes representing various stages of structural development with unique fuel load characteristics using a hierarchical clustering method. Two Landsat satellite images were then classified into vegetation/fuel classes using a hybrid unsupervised/supervised approach. A back-classification accuracy assessment, which uses the same pixels to test as used to train the classifier, produced an overall Kappa of 50% for the vegetation/fuels map. The map with fuel classes within vegetation type collapsed into single classes was verified with an independent dataset, yielding an overall Kappa of 80%.     

九华山佛茶文化旅游开发研究

九华山佛茶文化旅游既有历史优势,又有区位优势,开发九华山佛茶文化旅游是将九华山的佛教旅游资源与茶文化旅游资源中的寺院茶文化相结合。更新观念、重视特形象设计、丰富完善旅游产品、加大旅游商品开发和不断开拓旅游市场等是九华山佛茶文化旅游开发的重要举措。     

四川若尔盖湿地退化成因分析与对策研究

本文以四川若尔盖湿地为研究对象,主要贡献为：（1）应用卫星遥感数据对若尔盖湿地退化趋势进行了科学定量分析;（2）采用博弈论的分析方法对相关利益主体进行解析,在寻求利益均衡点的基础上,提出湿地保护性开发对策;（3）针对湿地退化因素提出了多种对策,其中生态移民的设想对保护四川若尔盖湿地较为适宜;（4）提出了“禁止-限制-发展”的产业结构调整思路,以指导湿地的合理开发利用。