用ART2神经网络方法进行结构的损伤识别

用ART2神经网络方法对建筑结构的损伤进行了识别 ,实验证明该方法的识别精度高 ,具有自动从环境中学习的能力 ,对未知的损伤 ,ART2网络将能自动地给出新的识别输出 ,即对未知的损伤类型也能够进行识别     

改进组件树在隧道裂缝识别中的应用*

为提高衬砌裂缝病害事故隐患识别率,解决隧道表面普遍存在的对比度低、噪声污染严重、光照不均匀等问题,采用Retinex方法对图像进行噪声抑制和细节增强,结合组件树算法快速建立组件树并剪枝,建立1种新的隧道衬砌裂缝识别算法。研究结果表明:改进后的算法可有效平衡图像光照,保护图像中裂缝边缘信息,识别精度大于95%。研究结果可为识别隧道裂缝引起的安全隐患提供新的方法。     

石化乙烯工业废水中关键毒性物质的鉴别

借鉴美国环保署制定的毒性物质鉴别评价技术(TIE),直接从企业生产的工艺出发,结合废水的主要水质指标对某石化厂乙烯工业废水进行毒性鉴别试验,发现废水中的苯和硫化物对大型蚤具有明显的致死性,其中苯是废水中的关键毒物。所取废水对测试生物大型蚤的24 h-LC50均值为53.68%,其中主要致毒物质苯的含量大约30 mg/L。     

运用风险管理理念,提高灭火救援水平

根据消防部队灭火救援工作中的职业危险 ,引入了风险管理理念。笔者运用安全系统工程的理论和方法 ,建立了灭火救援工作的风险管理方法以及风险识别、风险评价的方法和步骤 ,并针对当前的情况 ,提出风险控制的具体措施。该方法简单 ,易于操作。在安全管理工作中应用风险管理方法 ,根据现有资料和知识经验 ,针对部门的具体情况 ,找出灭火救援工作中存在的风险 ,并对各种风险及其危险程度进行评价 ,在此基础上 ,采取相应的控制措施。分析和研究表明 ,运用风险管理有利于控制或减少消防人员在灭火救援中存在的风险 ,防范事故发生 ,提高灭火救援的水平。     

一株菲降解菌的鉴定及降解特性

从沈阳北部污水处理厂曝气池活性污泥中驯化和分离得到一株以菲为碳源的降解菌株W12,根据菌株形态和16S r DNA基因测序分析,该菌株鉴定为耳炎假单胞菌(Pseudomonas otitidis.).该菌株降解菲的最佳环境条件为:温度为30℃,p H值为7.0,摇床转速为170 r·min-1,接种量为10%,盐度为0.5%;菲初始质量浓度为1000 mg·L-1培养96 h后,降解率为65.80%,且对菲的最大耐受浓度为2000 mg·L-1;加入蛋白胨和酵母膏后,降解率分别提高到75.65%和70.85%.     

二次爆破个别飞石伤人事故分析

对某矿场二次爆破个别飞石伤人事故进行鉴定,通过实地勘测、调查取证,分析了两种裸露药包法爆破大块时可能发生的空气冲击波和个别飞石安全距离,认为该矿场二次爆破产生的个别飞石,可以飞达160m处对人员造成伤害。     

Monitoring of 943 organic micropollutants in wastewater from municipal wastewater treatment plants with secondary and advanced treatment processes

To perform a systematic survey on the occurrence and removal of micropollutants during municipal wastewater treatment, 943 semi-volatile organic chemicals in 32 wastewater samples including influents of secondary treatments, secondary effluents and final effluents(effluents of advanced treatments), which were collected from seven full-scale municipal wastewater treatment plants(MWTPs) in China, were examined by gas chromatography-mass spectrometry(GC-MS) coupled with an automated identification and quantification system with a database(AIQS-DB). In total, 196 and 145 chemicals were detected in secondary and final effluents, respectively. The majority of the total concentrations(average removal efficiency, 87.0%±5.9%) of the micropollutants were removed during secondary treatments. However, advanced treatments achieved different micropollutant removal extents from secondary effluents depending on the different treatment processes employed. Highly variable removal efficiencies of total concentrations(32.7%–99.3%) were observed among the different advanced processes. Among them,ozonation-based processes could remove 70.0%–80.9% of the total concentrations of studied micropollutants. The potentially harmful micropollutants, based on their detection frequency and concentration in secondary and final effluents, were polycyclic aromatic hydrocarbons(PAHs)(2-methylnaphthalene, fluoranthene, pyrene, naphthalene and phenanthrene), phosphorus flame retardants(tributyl phosphate(TBP), tris(2-chloroethyl)phosphate(TCEP) and tris(1,3-dichloro-2-propyl) phosphate(TDCP)), phthalates(bis(2-ethylhexyl)phthalate(DEHP)), benzothiazoles(benzothiazole,2-(methylthio)-benzothiazol, and 2(3H)-benzothiazolone) and phenol. This study indicated that the presence of considerable amounts of micropollutants in secondary effluent creates the need for suitable advanced treatment before their reuse.     

基于描述函数法的典型结构非线性识别方法研究

目的为典型的结构非线性提供识别方法。方法基于动力学基本理论,对典型结构非线性系统在建模时,将非线性单元产生的非线性力作为位移或速度的函数加入到潜在的线性系统中,对不同激励量级的频响函数加以分析,通过描述函数法识别非线性单元的位置、类型和参数。结果通过Matlab编程进行仿真验证,使用描述函数法对非线性系统进行识别,成功对三种不同情况的非线性系统实现了非线性单元识别。结论描述函数法识别的非线性位置是准确的,类型是匹配的,参数准确度极高。     

Does the potential safety risk affect whether particular construction hazards are recognized or not?

Introduction: Evidence from the global construction industry suggests that an unacceptable number of safety hazards remain unrecognized in construction workplaces. Unfortunately, there isn’t a sufficient understanding of why particular safety hazards remain unrecognized. Such an understanding is important to address the issue of poor hazard recognition and develop remedial interventions. A recent exploratory effort provided anecdotal evidence that workers often fail to recognize safety hazards that are expected to impose relatively lower levels of safety risk. In other words, the research demonstrated that the underlying risk imposed by a safety hazard can affect whether a hazard will be recognized or not. Method: The presented research focused on empirically testing this preliminary finding. More specifically, the study tested the proposition that Construction workers are more likely to recognize safety hazards that impose higher levels of safety risk than those that impose relatively lower levels of safety risk. The research goals were accomplished through a number of steps. First, a set of 16 construction case images depicting a variety of construction operations that included a number of known safety hazards was presented to a panel of four construction safety experts. The experts were tasked with examining each of the known safety hazards and providing a rating of the relative safety risk that the individual hazards impose. Having obtained an estimate of the underlying safety risk, a hazard recognition activity was administered to 287 workers recruited from 57 construction workplaces in the United States. The hazard recognition activity involved the examination of a random sample of two construction case images that were previously examined by the expert panel and reporting relevant safety hazards. Results: The results of the study provided support for the proposition that workers are more likely to recognize hazards that impose relatively higher levels of safety risk. Practical Applications: The findings of the study can be leveraged to improve existing hazard recognition methods and develop more robust interventions to address the issue of poor hazard recognition levels.     

煤制油基地安全激励因素识别及安全动机模型的实证研究

为探求安全是否需要激励以及如果采用激励、从何激励的问题,对848名煤制油基地的员工进行问卷调查,将员工需求分为低层次需求、尊重需求、成就实现需求和超越自我需求4个方面,对每个具体需求构建需求场景。对控制变量进行差异性检验分析和相关性分析,得出文化程度和年龄对不同层次需求的影响,在此基础上进行结构方程模型验证分析。结果表明:安全需要激励,低层需求和成就需求大于尊重需求,超我需求最小,负向激励不受欢迎;受欢迎的因素在不同年龄和文化下略有差异,考核制度、人际关系、物质激励等均排在前列,且安全动机由经济性满足和自我价值实现共同确定,精神激励制度不是安全动机的核心要素。