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231.
针对民机人因防错设计对飞行安全的影响,从世界民航安全事故/事件数据库中筛选出92起典型的人为因素事故案例,采用基元事件分析法进行深度分析,提炼出民机人因防错设计需要考虑的重要设计因素,并建立重要设计因素集。基于系统工程学的“人机环”模型,结合国内外飞机设计相关标准,建立民机人因防错设计重要因素指标体系。运用模糊层次分析法对因素指标进行权重计算,确立影响飞行安全的14项人因防错设计关键因素,并针对这些关键因素提出民机人因防错设计通用要求,以期为民机人因防错设计满足初始适航要求提供参考。  相似文献   
232.
本文对自制管理样的定值及应用做了描述,样品采自新疆吐鲁番地区红、黄壤土,分析定值采用内检、外检方式,数据经统计检验处理,以多组均值求得总平均值作为元素的含量估计值,用±2S表示测量的单项不确定度.在土壤背景值研究等工作中应用的结果,各元素相对标准偏差(RSD)为:汞、镉大于 10%,铜、铅、锌、镍、氟均小于 10%。  相似文献   
233.
利用合适的坐标变换将钢筋混凝土板的弯曲问题变换为各向同性板弯曲问题。由弹性薄板的虚功原理及最小平方误差法计算各向同性板弯曲变形,得到原正交各向异性薄板的挠度方程。算例表明,在近似函数选取合理的情况下,该方法简单,计算时间短,具有较高的精确度。  相似文献   
234.
以安全管理理论、组织理论、风险管理理论为基础,在对多家煤矿实地调研的基础上,提出第三类危险源是造成组织失误的根本原因,预防第三类危险源的根本方法是编制风险管理计划;实例分析了陈家山矿某巷道实施风险管理整个过程,通过风险管理计划实施与运用,检查危险源是否在可接受风险水平下得到控制。风险管理可以对危险源的风险状态持续的检查,发现问题及时纠正,使危险源的风险状态降级,以便消除危险源。根据风险管理计划进行煤矿安全组织风险预警,其目的是为了保证煤矿安全管理组织活动处于安全、可靠的运行状态,并预测、监控、纠正各种不安全行为。陈家山矿风险管理研究对预防组织失误有现实意义。  相似文献   
235.
ABSTRACT: The Hanging Gardens are a unique feature of Zion National Park. Knowledge of the source and residence time of water discharging from the Hanging Gardens is necessary to help preserve these features. Ground-water chemical and isotopic data distinguish the discharge from seeps and springs into two groups, one of low and one of high conductivity. Water with low conductivity likely originates as recharge near the seeps and springs, and it only interacts with the Navajo Sandstone. High conductivity water, on the other hand, originates as recharge on the tops of plateaus to the east, where it interacts with marine rocks of the Carmel Formation. Carbon dating of these ground waters indicates that the low conductivity water is essentially modern recharge, while the high conductivity water was recharged 1,000 to 4,000 years ago.  相似文献   
236.
主要从行为科学的基本理论出发,通过对航空维修人为差错的统计分析,寻求人为差错的行为类型、特点及预防人为差错的基本对策  相似文献   
237.
ABSTRACT Necessary input parameters for studying mixing zone characteristics of thermal plumes are horizontal surface and subsurface water velocities. Using time lapse aerial photography and analytical photogrammetric techniques, movements of drogues in an effluent plume were traced. From these traces accurate velocity vectors were obtained. Photographic coordinates of drogue images were measured using a glass scale. From the photo coordinates and the results of a ground control survey, an analytical solution was made for positions of drogues in the water at known intervals of time. Drogue positions were mapped for selected exposures thereby providing a visual display of velocity vectors in the study area. A rigorous error analysis was performed to determine the validity of the computed results.  相似文献   
238.
PROBLEM: How can human contributions to accidents be reconstructed? Investigators can easily take the position a of retrospective outsider, looking back on a sequence of events that seems to lead to an inevitable outcome, and pointing out where people went wrong. This does not explain much, however, and may not help prevent recurrence. METHOD AND RESULTS: This paper examines how investigators can reconstruct the role that people contribute to accidents in light of what has recently become known as the new view of human error. The commitment of the new view is to move controversial human assessments and actions back into the flow of events of which they were part and which helped bring them forth, to see why assessments and actions made sense to people at the time. The second half of the paper addresses one way in which investigators can begin to reconstruct people's unfolding mindsets. IMPACT ON INDUSTRY: In an era where a large portion of accidents are attributed to human error, it is critical to understand why people did what they did, rather than judging them for not doing what we now know they should have done. This paper helps investigators avoid the traps of hindsight by presenting a method with which investigators can begin to see how people's actions and assessments actually made sense at the time.  相似文献   
239.
ABSTRACT: Developing a mass load estimation method appropriate for a given stream and constituent is difficult due to inconsistencies in hydrologic and constituent characteristics. The difficulty may be increased in flashy flow conditions such as karst. Many projects undertaken are constrained by budget and manpower and do not have the luxury of sophisticated sampling strategies. The objectives of this study were to: (1) examine two grab sampling strategies with varying sampling intervals and determine the error in mass load estimates, and (2) determine the error that can be expected when a grab sample is collected at a time of day when the diurnal variation is most divergent from the daily mean. Results show grab sampling with continuous flow to be a viable data collection method for estimating mass load in the study watershed. Comparing weekly, biweekly, and monthly grab sampling, monthly sampling produces the best results with this method. However, the time of day the sample is collected is important. Failure to account for diurnal variability when collecting a grab sample may produce unacceptable error in mass load estimates. The best time to collect a sample is when the diurnal cycle is nearest the daily mean.  相似文献   
240.
大空间火灾实验中温度测量的误差分析   总被引:2,自引:0,他引:2  
在大空间火灾实验中,由于测温系统的庞大和复杂,导致影响温度测量的误差因素增多。该文主要从热电偶测温误差理论分析入手,讨论全尺寸火灾实验温度测量误差的因素和大小,阐述了大空间烟气温度测量的误差引入方式和减少误差的措施,并对一组大空间内火灾机械排烟实验的温度数据进行了误差分析。  相似文献   
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