基于模糊综合识别技术的粉尘危害评价应用研究

针对目前粉尘危害评价存在的不足,采用最优权法确定各评价指标的权系数,利用模糊识别技术对粉尘危害程度进行综合评价,初步建立了粉尘危害评价指标体系和评价分级标准.结合某矿山实例,对粉尘危害进行模糊综合评价.评价结果表明,模糊综合识别技术能够较好反应实际情况,是一种有效的评价方法,对粉尘防治工作具有一定的指导意义.     

基于NDVI指数的骆马湖水生植被分级研究

基于典型时段骆马湖LandsatTM遥感影像,利用归一化植被指数（NDVI）法对骆马湖水生植被进行分级研究.采用标准差分级方法,将骆马湖水生植被分为5个等级.研究结果表明,利用这种分级方法处理的图像能够较准确地反映骆马湖水生植被区域分布和等级分区,能够更准确地给出采砂区和生态保护区域的位置,增强湖区水生态环境保护工作的有效性和针对性.     

精确三维光谱数据活性关系方法应用于ToxCast数据库中雌激素受体数据分类、验证和特征提取的建模策略

本文利用三维光谱数据活性关系方法(3D-SDAR)对ToxCast数据库中1 528种化合物的雌激素潜能(表示为18分复合高通量筛选生物测定)进行建模。由于缺少170核磁共振(NMR)仿真软件,信息量最大的碳-碳3D-SDAR指纹随着一些指标变量增强,这些指标变量包括来自羰基和酰胺的氧原子、酯基、磺酰、硝基、脂肪族羟基和酚羟基官能团。为了评价本文作者所开发模型的预测性能的真实性,美国环境保护署为研究人员提供了2 008种化合物组成一套盲测。其中,543种化合物有文献可查数据—他们的结合力有助于评估开发模型的外部分类精度：得到预测精度0.62,敏感度0.71,和特异度0.53的结果。与其他建模技术相比,本文作者开发的模型几乎没有简化建模集和预测集之间的性能。3D-SDAR映射技术可以识别拟雌激素活性所必需的结构特征：1) 存在一个酚的OH官能团或环己烯酮,2)与第一苯酚环上的氧距离6 ?到8 ?的第二芳香或酚环,3) 存在一个与苯酚环的几何中心距离大约6 ?的甲基官能团,4)一个靠近(距离几何中心～4?)某个苯酚环的羰基官能团。
精选自Svetoslav H. Slavov, Richard D. Beger. Rigorous 3-dimensional spectral data activity relationship approach modeling strategy for toxcast estrogen receptor data classification, validation, and feature extraction. Environmental Toxicology and Chemistry: Volume 36, Issue 3, pages 823–830, July 2017. DOI: 10.1002/etc.3578
详情请见http://onlinelibrary.wiley.com/wol1/doi/10.1002/etc.3578/full
     

基于STAMP模型的建筑事故致因因素定量分析方法研究

为揭示建筑安全事故致因因素间的相互关系从而对其进行有效预防和控制,探讨1种STAMP模型的定量分析方法,用于深入剖析事故致因因素间的逻辑关系和属性特征。基于STAMP系统事故理论模型,从建筑工程安全控制结构入手逐层定性分析事故的致因因素;引入灰色DEMATEL与ISM相结合的方法对系统事故间的复杂逻辑关系进行层级划分;运用MICMAC分析计算各致因因素的驱动力和依赖度数值并判断其属性类别。结果表明:提出的定量分析方法运用到江西丰城冷却塔坍塌事故中的分析结果与事故调查报告相契合,能较全面地说明各层次结构间的相互作用。     

粉煤灰的组分特征及其系统分类

利用光学显微镜、X射线衍射及扫描电镜等手段,从岩石学角度对粉煤灰的组分特征进行了详细观察研究。结果表明:粉煤灰的组分可分为有机组分和无机组分两大类。有机组分包括煤粒和残炭2个亚组;而无机组分则可进一步分为玻璃微珠、磁铁微珠、不定形颗粒、碎屑石英和莫来石。在此基础上,首次提出了粉煤灰显微组分分类系统并对显微组分作了定量统计。      

Developing Rapid Methods for Analyzing Upland Riparian Functions and Values

Regulators protecting riparian areas need to understand the integrity, health, beneficial uses, functions, and values of this resource. Up to now most methods providing information about riparian areas are based on analyzing condition or integrity. These methods, however, provide little information about functions and values. Different methods are needed that specifically address this aspect of riparian areas. In addition to information on functions and values, regulators have very specific needs that include: an analysis at the site scale, low cost, usability, and inclusion of policy interpretations. To meet these needs a rapid method has been developed that uses a multi-criteria decision matrix to categorize riparian areas in Washington State, USA. Indicators are used to identify the potential of the site to provide a function, the potential of the landscape to support the function, and the value the function provides to society. To meet legal needs fixed boundaries for assessment units are established based on geomorphology, the distance from “Ordinary High Water Mark” and different categories of land uses. Assessment units are first classified based on ecoregions, geomorphic characteristics, and land uses. This simplifies the data that need to be collected at a site, but it requires developing and calibrating a separate model for each “class.” The approach to developing methods is adaptable to other locations as its basic structure is not dependent on local conditions.     

Work environment risk factors for injuries in wood processing

Problem

The reported injury rate for wood product manufacturing in Maine, 1987-2004, was almost twice the state-wide average for all jobs. Method: A case-control study was conducted in wood processing plants to determine preventable risk factors for injury. A total of 157 cases with injuries reported to workers' compensation and 251 controls were interviewed. Results: In multivariable analyses, variables associated with injury risk were high physical workload, machine-paced work or inability to take a break, lack of training, absence of a lockout/tagout program, low seniority, and male gender. Different subsets of these variables were significant when acute incidents and overexertions were analyzed separately and when all injuries were stratified by industry sub-sector. Impact on industry: Generalizability may be limited somewhat by non-representative participation of workplaces and individuals. Nevertheless, these findings provide evidence that many workplace injuries occurring in wood processing could be prevented by application of ergonomics principles and improved work organization.     

Using conditional inference forests to identify the factors affecting crash severity on arterial corridors

Introduction

The study aims at identifying traffic/highway design/driver-vehicle information significantly related with fatal/severe crashes on urban arterials for different crash types. Since the data used in this study are observational (i.e., collected outside the purview of a designed experiment), an information discovery approach is adopted for this study.

Method

Random Forests, which are ensembles of individual trees grown by CART (Classification and Regression Tree) algorithm, are applied in numerous applications for this purpose. Specifically, conditional inference forests have been implemented. In each tree of the conditional inference forest, splits are based on how good the association is. Chi-square test statistics are used to measure the association. Apart from identifying the variables that improve classification accuracy, the methodology also clearly identifies the variables that are neutral to accuracy, and also those that decrease it.

Results

The methodology is quite insightful in identifying the variables of interest in the database (e.g., alcohol/ drug use and higher posted speed limits contribute to severe crashes). Failure to use safety equipment by all passengers and presence of driver/passenger in the vulnerable age group (more than 55 years or less than 3 years) increased the severity of injuries given a crash had occurred. A new variable, ‘element’ has been used in this study, which assigns crashes to segments, intersections, or access points based on the information from site location, traffic control, and presence of signals.

Impact

The authors were able to identify roadway locations where severe crashes tend to occur. For example, segments and access points were found to be riskier for single vehicle crashes. Higher skid resistance and k-factor also contributed toward increased severity of injuries in crashes.     

Air classification of blast furnace dust collected in a fabric filter for recycling to the sinter process

Totally dry cleaning has become a common technology for top gas cleaning in blast furnaces in recent years. A significant advantage of totally dry gas cleaning is that the dust collected is obtained as dry powder, thus simplifying the recycling of the dust in the sinter plant and avoiding aqueous emissions. The concentration of some heavy metals, especially zinc, in the collected dust is usually higher than the maximum tolerable concentration for recycling to the sinter process. Therefore, a process for separation of dust with a low level of contamination from the rest is necessary to make partial recycling possible. This is possible because the limited components are more volatile and accumulate in the finer dust fraction. In wet blast furnace top gas cleaning, hydrocyclones are well established for this separation. For the separation of dry powder from the dry dedusting process air classification can be used. Dust from the top gas of a blast furnace with a fabric filter for dry top gas cleaning was split into several size fractions using a laboratory air classifier. The concentration of Ca, Cd, Cl, Cu, Fe, K, Na, Pb and Zn was analysed for each particle class and the loss on ignition was determined. A strong dependence of the concentration on the particle size was found for the more volatile metals, whereas the Fe and Ca concentration and the loss on ignition were quite evenly distributed. With the calculated recovery–removal-functions the possible recycling rate can be estimated for a given removal rate for the limited components.     

Maintenance-related major accidents: Classification of causes and case study

The potential for major accidents is inherent in most industries that handle or store hazardous substances, for e.g. the hydrocarbon and chemical process industries. Several major accidents have been experienced over the past three decades. Flixborough Disaster (1974), Seveso Disaster (1976), Alexander Kielland Disaster (1980), Bhopal Gas Tragedy (1984), Sandoz Chemical Spill (1986), Piper Alpha Disaster (1988), Philips 66 Disaster (1989), Esso Longford Gas Explosion (1998), Texas City Refinery Explosion (2005), and most recently the Macondo Blowout (2010) are a few examples of accidents with devastating consequences.Causes are being exposed over time, but in recent years maintenance influence tends to be given less attention. However, given that some major accidents are maintenance-related, we intend to concentrate on classifying them to give a better insight into the underlying and contributing causes.High degree of technological and organizational complexity are attributes of these industries, and in order to control the risk, it is common to deploy multiple and independent safety barriers whose integrity cannot be maintained without adequate level of maintenance. However, maintenance may have a negative effect on barrier performance if the execution is incorrect, insufficient, delayed, or excessive. Maintenance can also be the triggering event.The objectives of this article are: (1) To investigate how maintenance impacts the occurrence of major accidents, and (2) To develop classification schemes for causes of maintenance-related major accidents.The paper builds primarily on model-based and empirical approaches, the latter being applied to reports on accident investigation and analysis. Based on this, the Work and Accident Process (WAP) classification scheme was proposed in the paper.