改性涂料安全帽降温性能及热舒适的优越性分析

为探究高温户外作业下改性涂料安全帽在我国不同地区的隔热降温效果差异，本文采用Fluent数值仿真技术结合我国4个不同地区(北京、广州、南京、西藏)的太阳辐射特性，对比研究了改性安全帽和普通安全帽的降温性能及热舒适性差异。结果表明：改性安全帽相比普通安全帽可使帽体表面温度降低10℃左右，同时帽内外部温差降低3～4℃，说明改性安全帽能够有效降低太阳辐射得热；对于4个不同地区，改性安全帽相比普通安全帽的帽内温度可降低5～7℃，并且当太阳辐射量大于1 200 W/m²时，改性安全帽的降温性能愈发显著。进一步研究发现，相比佩戴普通安全帽，佩戴改性安全帽可使人体TEQ指数降低7.6%～9.6%，说明佩戴改性安全帽能够扩大作业者可从事体力劳动的工作范围，可提高户外安全帽佩戴者的热舒适性。     

基于机器学习方法的安全帽佩戴行为检测

施工现场作业人员是否佩戴安全帽主要依靠人工检查,存在监管效率低、时效性差等问题,为了实时自动监管作业人员是否佩戴安全帽,提出1种基于机器学习的安全帽佩戴行为检测方法。首先利用深度学习YOLOv3算法检测出现场视频中的施工人员脸部位置,根据安全帽与人脸的关系估算出安全帽潜在区域;然后对安全帽潜在区域图像进行增强处理,使用HOG（方向梯度直方图）提取样本的特征向量;再利用SVM（机器学习的支持向量机）分类器对脸部上方是否有安全帽进行判断,进而实现对施工人员安全帽佩戴行为的实时检测与预警。以某高铁站施工现场为例进行验证,研究数据表明在施工通道和塔吊作业区域,该方法可实时有效检测出工人未佩戴安全帽的行为,识别率达90%。     

从管理人员不会戴安全帽说起

这不是笑话,而是一个真实的事,一次下车间劳动,见到安监科的同志教一名“老机关”怎样佩戴安全帽,联想到一些管理人员平时拿安全帽当摆设的现象,不由得想议论上几句。 安全帽的佩戴是有一定要求的,其保护作用与能否正确佩戴有直接关系的道理也是很明显的。按要求佩戴,安全帽才能在关键时刻保安全,反之,其保护作用就会大打折扣。因此,安全帽佩戴得不正确,表现出随意性,实质是拿着安全当儿戏。说它是安全工作中的一个薄弱点,或者是安全观念不强的一个反映,或者是自我安全保护意识不强的一种流露,都不为过份。     

基于深度学习的建筑工人安全帽佩戴识别研究

建筑工人头部伤害是造成建筑伤亡事故的重要原因。佩戴安全帽是防止建筑工人发生脑部外伤事故的有效措施,而在实际工作中工人未佩戴安全帽的不安全行为时有发生。因此,对施工现场建筑工人佩戴安全帽自动实时检测进行探究,将为深入认知和主动预防安全事故提供新的视角。然而,传统的施工现场具有安全管理水平低下、管理范围小、主要依靠安全管理人员的主观监测并且时效性差、不能全程监控等一系列问题。针对上述现状,提出了一种基于Tensorflow框架,具有高精度、快速等特性的Faster RCNN方法,实时监测工人安全帽佩戴状况。为评估模型性能,收集了6 000张图像用于模型的训练与测试,结果表明,该模型识别工人安全监测中佩戴安全帽工人的平均精度达到90. 91%,召回率达到89. 19%;识别未佩戴安全帽工人的精度达到88. 32%,召回率达到85. 08%。同时,针对工人未佩戴安全帽而进入施工现场的违规行为,通过施工现场入口处监控摄像头截取视频流图像帧,设置检验试验,验证了本方法在施工现场实际应用的有效性。     

基于改进的YOLOv4安全帽佩戴检测研究

为了加强建筑工人佩戴安全帽情况的检测,防止安全事故的发生,提出1种改进的轻量级YOLOv4安全帽佩戴检测算法,用于运行在移动设备端,降低现场部署的条件;制作1个8 000幅图像的数据集,用于训练和评估安全帽检测算法;为了评估改进的YOLOv4的性能,从5个不同建筑工地采集到600张施工人员图像和60条施工视频作为验证集;根据建筑工地不同的视觉条件对图像进行分类,用于验证本文算法在不同外界环境下的性能。结果表明:改进后的模型检测速度是YOLOv4的3.4倍,可用于实时检测施工人员在不同施工现场条件下是否佩戴安全帽的情况,有利于提高安全检查和监督水平。     

安全帽

在劳动现场,经常存在坠落物冲击人体的危险。由于高处坠落物的冲击力大,极易造成伤亡事故,戴用安全帽则可在一定程度上防止或减缓这类事故的发生。高空作业者有时不慎坠落,如果戴着安全帽,就可减轻或避免头部的损伤。 国家有关劳动保护法规规定,进入上述现场的人员,都要佩戴安全帽。但长时期以来,只有一个量的规定而缺乏质的标准。有些安全帽由于质量不好,经受不起冲击,实际上是不安全的。人们还习惯地将安全帽使劲摔打,以碎不碎作为唯一的检验标准,但戴用这种“安全”帽,有时却受到了冲击伤害。安全帽国家标准(GB 2811-81)的正式实施,使安…     

三宝

安全帽皇冠只有一个人佩戴,却给千万人酿造了灾难。安全帽人人一顶,却是救生的宝船。 安全带挂上这根缆绳,把生命之船停稳在每一个平安的港湾。 安全网鱼网能打捞肥美,安全网可以兜住幸福。三宝@陈雨田     

四面八方

北京城建二公司示范安全帽佩戴法安全帽不仅要质量合格,而且要使职工正确佩戴使用,这是北京市城建二公司现场抓安全管理"严细深实"所提出的明确要求。日前,北京城建二公司二经理部承建的海淀看守所工程开工后,项目部狠抓现场安全管理教育工作,对外施民工入场一批教育     

谈谈安全帽

安全帽在保护劳动者头部在生产作业中免受损伤或减轻伤害方面,发挥了相当有效的作用。许多企业中工人都称安全帽为救命帽;建筑部门把它作为安全生产三宝之一,并规定进入作业场所必须佩戴。 在国外,工业管理比较先进的国家都明确规定:上至厂长,下至任何工作人员,只要进入厂区,都必须佩戴安全帽,而且对不同职务的人员,在其安全帽上,都做有明显的不同标记,以便于指挥。国外安全帽的品种很多,除一般工业用和军用外,还有乘车用安全帽(保护摩托车驾驶员和乘员)、电业专用安全帽、消防安全帽、运动防护帽(爬山、骑马、赛车等)。此外,国外还生产一些…     

嵌入式智慧工地安全帽检测系统设计与实现

针对施工作业人员不佩戴安全帽的问题,设计了一种基于计算机视觉的嵌入式智慧工地安全帽检测系统并进行了实用性的算法改进,解决了人力检测效率低下、标准不一的问题,同时提升了在目标检测领域小目标检测的精度。介绍了人工和传统算法在安全帽佩戴监管方面的弊端以及嵌入式系统的优势,详细介绍了算法优化的方法以及本系统的实验结果。     

基于雷电监测预警的加油站防雷预案执行研究

基于雷电监测预警技术,提出了一种新型的加油站防雷预案执行方案,解决了现有的应急预案无准确执行依据的问题。方案引入近几年成熟的电场监测和雷电定位技术,对加油站周边地区的电场和雷击情况进行实时监测,并基于监测数据和加油站业务特点建立数学模型,结合先进的物联网和云计算技术,在雷电发生前获得高精度的短时雷电预警信息,在此基础上设计了加油站防雷预案执行方案,最后对方案的应用效果进行了分析。     

LFT-G注塑工艺在玻璃钢安全帽生产中的应用

玻璃钢安全帽因具有强度高、耐高温,耐水、酸、碱、油、化学腐蚀及良好的绝缘性等特点,被广泛应用于石油化工、矿山、电力、冶炼等多个行业。目前,玻璃钢安全帽的生产工艺仅有两种,一是手糊,二是模压。但这两种生产工艺不仅存在粉尘、噪声、有毒物质等多种职业危害因素,而且由于部分关键工序采用手工制作,因而造成玻璃钢安全帽的质量性能的不稳定。使用LFT-G（长纤维增强热塑性塑料颗粒）作为原材料,将注塑工艺引进玻璃钢安全帽的生产中,实现了玻璃钢安全帽的注塑生产。这种工艺,不仅职业危害因素大大减少,而且也因关键工序中不存在手工作业,从而大大增加了玻璃钢安全帽质量的稳定性,同时,由于LFT-G粒料的长度增加,经过加工后,安全帽成品中的纤维长度也会增加,使得安全帽的抗冲击性能等满足标准要求。为此,以LFT-G为基础的玻璃钢安全帽的注塑工艺具有广阔的应用前景。     

采用冲击加速度指标评价安全帽抗侧向冲击性能的研究

安全帽是应用最为广泛的一种重要的劳动作业人员头部安全防护用品,广泛使用在机械、建筑、矿山、交通、冶金、电力等行业中。在实际工作中,作业人员除可能受到来自顶部的坠落冲击外,还切实存在着受到侧面冲击的可能。现行安全帽国家标准主要采用头部受到的冲击力数值大小作为依据评价安全帽防护性能的优劣,此种方法无法用来考察安全帽的抗侧向冲击性能。本文讨论引入冲击加速度作为新的评价指标,以达到科学评价安全帽抗侧向冲击防护性能的目的。     

基于YOLOv3的电网作业人员安全帽佩戴检测

为了有效监测电网作业人员不规范佩戴安全帽行为,提出1种基于YOLOv3的电网作业现场安全帽佩戴检测方法.针对安全帽佩戴规范性问题,构建正确佩戴、不正确佩戴和未佩戴安全帽3种情况下的图像样本库;并利用该数据库对YOLOv3模型进行训练与测试,结合模型参数、样本比例及算法对比分析,开展电网作业人员安全帽佩戴检测算例.结果表...     

The effects of a mandatory motorcycle helmet law on helmet use and injury patterns among motorcyclist fatalities

BACKGROUND: The National Highway Traffic Safety Administration (NHTSA) has found that motorcycle helmets are 37% effective in preventing death and 65% effective in preventing brain injuries in a crash. Unfortunately, in 1995 Congress lifted federal sanctions against states without helmet laws and since then there have been a number of primary motorcycle helmet laws repealed or weakened. More lives could be saved and serious injuries avoided if there was increased helmet use throughout the United States. METHODS: This study analyzed helmet use and injury patterns among motorcycle riders in the United States involved in fatal crashes from 1995 through 2003 and compared the results between states with and without a primary helmet law. Age, sex, injury severity and helmet use are some of the variables obtained from the Fatality Analysis Reporting System (FARS). RESULTS: In the 20 states and the District of Columbia, which currently have a primary helmet law, 84.0% of fatally injured riders were wearing a helmet. In the 27 states with a secondary helmet law, 36.2% of fatalities used a helmet, and in the remaining three states with no law at all, helmet use dropped to 17.6%. In the two states (Arkansas and Texas) that changed from a primary helmet law to a secondary helmet law in 1997, helmet use decreased from 78.2% in 1996 to 31.7% in 2000. CONCLUSION: If all states were to enact a primary motorcycle helmet law, helmet use would dramatically increase while decreasing the number of motorcyclist head injuries and fatalities. IMPACT ON INDUSTRY: The results of this study will hopefully persuade law makers to enact primary helmet laws in all states throughout the nation. Helmet manufacturers can use this data to design more comfortable helmets while also improving upon the protective qualities of these safety devices.     

Risk compensation? The relationship between helmet use and cycling speed under naturalistic conditions

Introduction: An argument against mandatory helmet use is based on the idea of risk compensation, which means that cyclists might ride faster when wearing a helmet (Lardelli-Claret et al., 2003). However, questionnaire and experimental studies were unable to find evidence for this assumption (Fyhri et al., 2012; Fyhri & Philipps, 2013). Simultaneously, other factors with a potential role in helmet use and cycling speed, such as trip length and rider characteristics have been neglected in such considerations. The goal of the analysis presented in this paper was therefore to investigate the relationship between helmet use and cycling speed under naturalistic conditions while taking characteristics of cyclists and bicycles into account. Method: As part of a naturalistic cycling study, we equipped the bicycles of conventional and e-bike riders with data acquisition systems to record speed and trip distance. It included two cameras (one for the face of the participant, another one for the forward scenery). For the analysis presented in this paper, we used the data of 76 participants (28 conventional bicycles, 48 e-bikes). Results: In total, participants used their helmet for 56% of all trips. Helmets were used more frequently for longer trips. A linear mixed model, in which trip length, helmet use, bicycle type, age, and gender were used as predictors showed that helmet use did not play a significant role for cycling speed. Instead, all other factors that were analyzed, with the exception of gender, had a significant relationship to cycling speed. Discussion: The assumption of risk compensation as a result of the use of a helmet could not be confirmed. Instead, the findings seem to support the suggestion that cyclists who undertake trips at potentially higher speed levels are aware of their increased risk, and actively try to reduce it through the use of a helmet.     

一种分离式可降温安全帽设计

为了解决高温作业环境下安全帽内部微环境积热严重问题,运用ANSYS软件模拟分析了安全帽内部微环境积热的空间和时间分布情况。基于模拟结果,设计了一款分离式可降温安全帽,其由帽体、喷嘴、风管、风机和开关组成。在高温高湿环境下,模拟人员分别佩戴在帽衬带上装有温度传感器的普通安全帽和分离式可降温安全帽进行剧烈运动模拟高温作业人员高强度劳动,记录其温度变化。结果表明:分离式可降温安全帽有良好的降温效果,同时具有不破坏安全帽的结构和强度,几乎不增加安全帽重量,无噪声、无电磁辐射,拆装简便等优点。     

Measurements and predictions of harmful releases of the gathering station over the mountainous terrain

Having a risk analysis of harmful releases over mountainous terrains through wind tunnel experiment is a frontier problem in China. In this paper, a straight-flow wind tunnel is applied to simulate the atmospheric boundary layer and research the motion of high-sulfur gas released to atmosphere when accidental releases occur in a gathering station over the mountainous terrain. After an analysis of hourly concentration in the field accident for eight wind directions, experimental results reveal that nearby concentration fields are dominated by wind and far-field concentration distribution is dominated by topography, which leads to complete levels of consequence impact for the personnel risk inside and around the gathering station. Based on CFD techniques, a three-dimensional modelling was established in comparison with the wind tunnel experiment, which suggests that CFD prediction had underestimated the near-field gas concentration and the performance could not precisely match actual risks the gathering station causes to the mountainous terrain, which leads to a modified equation for numerical prediction. Instead of proposing a lower personnel risk evaluation obtained through the use of CFD techniques, the wind tunnel experiment offers a new choice for the consequence impact analysis for the petrochemical industry in China.