自燃火灾巷道烟流的数值模拟及安全评价

笔者以铜坑矿为工程实例,利用矿井火灾巷道烟气流动所遵循的基本守恒方程组和控制方程组,对烟气流动特性进行数值模拟,得出了自燃火灾巷道内烟气流动的速度场、温度场详细分布情况。并采用预计热舒适指标(PMV)、预计不满意百分比(PPD)对巷道中的空气质量进行了安全评价。结果表明采用数值模拟法对于研究矿山自燃火灾巷道内烟气流动的运动情况更为直观,可视化强;采用的热舒适度评价指标更突出了以人为本。通过模拟计算结果,可以为铜坑矿地下火和毒气蔓延的控制以及火区特大事故应急救援预案的制定提供技术依据。     

Components of information for multiple resolution comparison between maps that share a real variable

This paper presents quantitative methods that allow scientists to compare the patterns in two maps that show a shared real variable. Specifically, this paper shows how to budget various components of agreement and disagreement between maps. The components are based on the separation of a map’s information of quantity from its information of location. The technique also examines how variation in resolution influences the measurement of the components of information. The manner in which the measurements change as a function of spatial resolution can be more important and interesting than the results at any single particular resolution, because the results at a single particular resolution may indicate more about the format of the data than about the overall pattern in the landscape. An example illustrates the mathematical concepts, and an application compares mapped vegetation indices in Africa to illustrate the usefulness of the proposed approach vis-à-vis a conventional approach. The results are presented visually in the form of stacked bar graphs that show separable components of information. The entire analysis is performed twice, each time with a different mathematical measurement of deviation: (1) root mean square error, and (2) mean absolute error. This paper compares these two approaches and discusses their relative advantages and disadvantages. Hopefully, this approach of budgeting components of information at multiple resolutions will become adopted as standard practice in the measurement of patterns.

A systems perspective of managing error recovery and tactical re-planning of operating teams in safety critical domains

Introduction

Research in human error has provided useful tools for designing procedures, training, and intelligent interfaces that trap errors at an early stage. However, this “error prevention” policy may not be entirely successful because human errors will inevitably occur. This requires that the error management process (e.g., detection, diagnosis and correction) must also be supported. Research has focused almost exclusively on error detection; little is known about error recovery, especially in the context of safety critical systems. The aim of this paper is to develop a research framework that integrates error recovery strategies employed by experienced practitioners in handling their own errors.

Method and Results

A control theoretic model of human performance was used to integrate error recovery strategies assembled from reviews of the literature, analyses of near misses from aviation and command & control domains, and observations of abnormal situations training at air traffic control facilities. The method of system dynamics has been used to analyze and compare error recovery strategies in terms of patterns of interaction, system affordances, and types of recovery plans. System dynamics offer a promising basis for studying the nature of error recovery management in the context of team interactions and system characteristics.

Impact on industry

The proposed taxonomy of error recovery strategies can help human factors and safety experts to develop resilient system designs and training solutions for managing human errors in unforeseen situations; it may also help incident investigators to explore why people's actions and assessments were not corrected at the time.     

ISC3模式对高架点源输入参数的探讨

为分析ISC3模式中参变量的相对重要性及各参变量对模式预测结果的影响程度,采用2000年北京市全年气象统计资料,利用ISC3模拟火电厂高架点源排放,对应用广泛的ISC3空气质量模式进行了误差和灵敏度分析,结果表明:高架点源预测过程中,源强、风速、混合层高度和稳定度类型对模拟结果影响较显著,且为全程影响;排放温度、排放速度和环境温度在近距离影响较显著,对于远距离影响较小。     

Adding rigor to ecological network models by evaluating a set of pre-balance diagnostics: A plea for PREBAL

The widespread use of ecological network models (e.g., Ecopath, Econetwrk, and related energy budget models) has been laudable for several reasons, chief of which is providing an easy-to-use set of modeling tools that can present an ecosystem context for improved understanding and management of living marine resources (LMR). Yet the ease-of-use of these models has led to two challenges. First, the veritable explosion of the use and application of these network models has resulted in recognition that the content and use of such models has spanned a range of quality. Second, as these models and their application have become more widespread, they are increasingly being used in a LMR management context. Thus review panels and other evaluators of these models would benefit from a set of rigorous and standard criteria from which the basis for all network models and related applications for any given system (i.e., the initial, static energy budget) can be evaluated. To this end, as one suggestion for improving network models in general, here I propose a series of pre-balance (PREBAL) diagnostics. These PREBAL diagnostics can be done, now, in simple spreadsheets before any balancing or tuning is executed. Examples of these PREBAL diagnostics include biomasses, biomass ratios, vital rates, vital rate ratios, total production, and total removals (and slopes thereof) across the taxa and trophic levels in any given energy budget. I assert that there are some general ecological and fishery principles that can be used in conjunction with PREBAL diagnostics to identify issues of model structure and data quality before balancing and dynamic applications are executed. I humbly present this PREBAL information as a simple yet general approach that could be easily implemented, could be considered for further incorporation into these model packages, and as such would ultimately result in a straightforward way to evaluate (and perhaps identify areas for improving) initial conditions in food web modeling efforts.     

Assessment of exposure to PCB 153 from breast feeding and normal food intake in individual children using a system approach model

Investigators have typically relied on a single or few discrete time points as measures of polychlorinated biphenyl (PCB) body burden, however health effects are more likely to be the result of integrative exposure in time, optionally expressed as an area under the time curve (AUC) of PCB serum concentration. Using data from a subgroup of 93 infants from a birth cohort in eastern Slovakia—a region highly polluted by PCBs—we fit a system type model, customized to our longitudinal measures of serum PCB concentrations in cord, 6, 16, and 45 month blood specimens. The most abundant congener, PCB 153, was chosen for modeling purposes. In addition to currently used methods of exposure assessment, our approach estimates a concentration time profile for each subject, taking into account mean residence time of PCB 153 molecules in the body, duration of breast feeding, hypothetical PCB 153 concentration in steady-state without breast feeding and alternately without normal food intake. Hypothetical PCB 153 concentration in steady-state without normal food intake correlates with AUC (r = 0.84, p < 0.001) as well as with duration of breast feeding (r = 0.64, p < 0.001). It makes possible to determine each subject’s exposure profile expressed as AUC of PCBs serum concentration with a minimum model parameters. PCB body burden in most infants was strongly associated with duration of breast feeding in most, but not all children, was apparent from model output.     

完善环境监测技术监督体系的思考

阐述了环境监测技术监督的概念及其重要性和必要性,分析了由于认识不到位、手段欠缺、机制不完善等原因而导致的技术监督作用的弱化表现。提出开展环境质量现状、污染源状况、开发区环境质量、环境管理措施绩效、监测科研课题等多项技术监督,利用报告、会议、区域目标考核等形式,建立多部门联动的环境质量分析会机制、项目审批过程的跟踪监测机制、环境管理污染防治的目标考核机制、监察处罚的效果点评机制、环境监测部门内部的资源整合机制,进一步完善技术监督体系。     

中国工业粉尘排放影响因素分解研究

粉尘排放是工业环境污染的重要部分,为了研究工业粉尘排放的主要动力以及应对措施,文章对2001-2009年的中国工业粉尘排放进行了趋势分析及影响因素分解。首先利用2001-2009年中国工业的产值与环境排放数据,描述了工业粉尘排放的基本情况,再采用对数平均迪氏指数法(LMDI)将工业粉尘排放的影响因素分解为规模效应、结构效应、技术效应和治理效应四部分,并比较分析了各子效应的影响程度及发展变化情况,结果表明规模效应仍是工业粉尘排放的重要动力,而结构效应将会是未来粉尘减排的关键方向。文章在将工业划分为6个子行业之后,根据粉尘的产生与排放量,选择化工及金属行业作为重点工业子行业进行影响因素分析,指出目前该子行业粉尘减排的主要方向应为充分发挥治理效应的减排作用。     

EDTA容量法测定硫酸根离子的误差分析

系统分析了ＥＤＴＡ容量法测定硫酸根离子的误差产生环节,并对各个环节提出了相应的误差控制办法。文中着重分析了由移液过程和滴定过程所产生的误差,最后指出,作为测定硫酸根离子的方法标准,ＥＤＴＡ容量法无法保证应有的精度,应由离子色谱法取代之     

在较高位置构筑大型隔声屏的降噪工程

在控制工厂二层楼顶的风机群及冷却塔群的噪声工程中，复式隔声屏获１８ｄＢ（Ａ）的降噪效果。主屏由轻结构板及隔振底盘组成。主习体被若干伸缩隔断以消除热应力。副屏是为了减少主屏隔振底盘缝的漏声。迷路消声构造减少伸缩缝的漏声。为了抗风，主习必须锚固，并且屏体自身应有良好的结构。