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61.
在安全生产总体形势逐步好转的情况下,中国职业病危害致病因素中粉尘和噪声占有不可忽视的分量.本文通过对国内外在线监测技术的发展现状的详细分析,引入国内外先进的粉尘和噪声在线监测技术构建了职业安全健康在线监测系统基本架构,对其基本工作性能和实际能产生的工作效果进行描述,并对其产生的科技进步性进行阐述.  相似文献   
62.
Objects in the terrestrial environment interact differentially with electromagnetic radiation according to their essential physical, chemical and biological properties. This differential interaction is manifest as variability in scattered radiation according to wavelength, location, time, geometries of illumination and observation and polarization. If the population of scattered radiation could be measured, then estimation of these essential properties would be straightforward. The only problem would be linking such estimates to environmental variables of interest. This review paper is divided into three parts. Part 1 is an overview of the attempts that have been made to sample the five domains of scattered radiation (spectral, spatial, temporal, geometrical, polarization) and then to use the results of this sampling to estimate environmental variables of interest. Part one highlights three issues: first, that relationships between remotely sensed data and environmental variables of interest are indirect; second, our ability to estimate these environmental variables is dependent upon our ability to capture a sound representation of variability in scattered radiation and third, a considerable portion of the useful information in remotely sensed images resides in the spatial domain (within the relations between the pixels in the image). This final point is developed in Part 2 that explores ways in which the spatial domain is utilized to describe spatial variation in remotely sensed and ground data; to design optimum sampling schemes for image data and ground data and to increase the accuracy with which remotely sensed data can be used to estimate both discontinuous and continuous variables. Part 3 outlines two specific uses of information in the spatial domain; first, to select an optimum spatial resolution and second, to inform an image classification.  相似文献   
63.
基于行为安全的建筑事故预防量化方法与实证研究   总被引:3,自引:2,他引:1  
在阐述安全行为(BBS)预防事故原理及其应用效果的基础上,选取某工程项目作为试验对象,结合我国建筑业一线工人的特点,对BBS实施中的培训方法、关键行为确认、观察方法3个关键环节进行具体试验。试验中建立了行为变化指数的图线,使用了安全行为指数(SI)来评定一线工人的安全行为及变化趋势。试验结果显示施工现场一线工人作业过程中的SI比基线期提高15%,表明所设计的BBS方法对于提高施工现场一线工人的行为安全性具有明显的效果。  相似文献   
64.
引入生态和气象研究领域的本底大气观测技术,提出一种便捷快速的温室气体本底浓度采样方法。该方法需要的设备简单,便于携带,能够快速完成采样。2011年5—7月,利用该方法,自西向东分别在处于我国三大阶梯的青藏高原东北缘、秦巴山区、长江中下游平原,选择不同类型的土地覆盖下垫面开展了地面采样实验,获得了33组以CO2和CH4为主的温室气体浓度数据。根据获得的采样结果,分别开展了人工采样数据分析及其与器测本底数据、卫星反演同期数据产品的对比分析,结果显示,几类数据趋势相符,数值相对偏差较低。总体认为,该方法获得的采样数据可靠、采样效率高,且成本低廉,这在我国温室气体自动监测站还比较少的现实情况下,不失为一种可选的快速便捷监测技术手段。  相似文献   
65.
The particulate matter (PM) pollution has been significantly improved by carrying out various valid emission control strategies since 2013 in China. Meanwhile the variation trend of nitrous acid (HONO) is worthy to investigate due to its vital role in the atmospheric oxidation process. In this study, field observation in the winter is conducted to investigate the concentration of HONO in an urban area of Beijing. In the winter of 2019, the mean HONO concentration is 1.38 ppbV during the whole winter. Photo-enhanced NO2 heterogeneous reactions on the ground and aerosol surfaces were found as the possible daytime sources of HONO. Compared to O3, photolysis of HONO dominates the primary OH sources during the winter time. To understand the HONO pollution patterns by years variation, multi-year data is summarized and finds that primary pollutants including CO and NO decreased, but secondary pollutants i.e., HONO (mostly generated via secondary process) increased. Our study highlights the requirement to mitigate secondary pollution by control HONO concentration.  相似文献   
66.
安徽数字测震台网地震编目分析   总被引:1,自引:0,他引:1  
安徽测震台网数字化系统运行以来,编目工作发生了巨大变化。地震震相分析均在数字化记录波形上进行标注,地震发生时刻、经纬度、震级由软件自动计算,生成地震目录和震相报告,数据质量有了很大提高。台网子台数量增加,地震定位更加准确,在地震预报研究工作中发挥了重要作用。  相似文献   
67.
谈地磁观测中的温度效应   总被引:1,自引:0,他引:1  
地磁场各要素的绝对数值是通过基线值来确定的,而基线值又与温度相关,是一条大致随温度变化的曲线。本文选取通海、贵阳、邵阳、天水等地磁台的基线值资料,计算各分量基线值与记录室温度的相关系数,判定基线值与温度之间的相关关系,掌握在不同记录室温度条件下,温度变化对地磁基线值以及地磁观测仪器的影响程度。以供其他地磁台站新建、改造观测记录室时借鉴。  相似文献   
68.
沙层应变观测是一个全新的前兆观测,目前对它的研究还非常少,用淮安台、怀来台及合肥台的数据进行了对比,通过日变化特征、长期变化特征、年变化特征、干扰因素及噪声分析几个方面,从而对该观测手段进行更进一步的分析。  相似文献   
69.
为评估深厚软土地区临近超浅埋地铁施工对盾构的扰动,结合斜交超浅埋地铁的某客运专线桩板结构路基工程,基于"第三方监测"的工程安全监控模式进行施工及试运营期间的安全评估,并研究了各阶段的变形规律及安全敏感因素。研究结果表明:地铁水平位移只出现于桩基施工阶段;沉降变形与收敛变形则贯穿于整个施工与运营阶段,变形值呈"增大—减小—稳定"的趋势;地铁变形中沉降影响最大,收敛变形次之,水平位移最小,且变形极值均小于安全限值,说明地铁结构是安全的;桩板结构有效控制了后续沉降的发生,大大降低了新建客运专线与既有地铁的相互影响。  相似文献   
70.
INTRODUCTION: The use of hand-held cellular (mobile) phones while driving has stirred more debate, passion, and research than perhaps any other traffic safety issue in the past several years. There is ample research showing that the use of either hand-held or hands-free cellular phones can lead to unsafe driving patterns. Whether or not these performance deficits increase the risk of crash is difficult to establish, but recent studies are beginning to suggest that cellular phone use elevates crash risk. METHODS: The purpose of this study was to assess changes in the rate of hand-held cellular phone use by motor-vehicle drivers on a statewide level in Michigan. This study presents the results of 13 statewide surveys of cellular phone use over a 4-year period. Hand-held cellular phone use data were collected through direct observation while vehicles were stopped at intersections and freeway exit ramps. Data were weighted to be representative of all drivers traveling during daylight hours in Michigan. RESULTS: The study found that driver hand-held cellular phone use has more than doubled between 2001 and 2005, from 2.7% to 5.8%. This change represents an average increase of 0.78 percentage points per year. The 5.8% use rate observed in 2005 means that at any given daylight hour, around 36,550 drivers were conversing on cellular phones while driving on Michigan roadways. The trend line fitted to these data predicts that by the year 2010, driver hand-held cellular phone use will be around 8.6%, or 55,000 drivers at any given daylight hour. CONCLUSIONS: These results make it clear that cellular phone use while driving will continue to be an important traffic safety issue, and highlight the importance of continued attempts to generate new ways of alleviating this potential hazard.  相似文献   
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