A system model for green manufacturing

Manufacturing systems evolution is afunction in multiple external and internal factors. With today’s global awareness of environmental risks as well as the pressing needs to compete through efficiency, manufacturing systems are evolving into a new paradigm. This paper presents a system model for the new green manufacturing paradigm. The model captures various planning activities to migrate from a less green into a greener and more eco-efficient manufacturing. The various planning stages are accompanied by the required control metrics as well as various green tools in an open mixed architecture. The system model is demonstrated by an industrial case study. The proposed model is a comprehensive qualitative answer to the question of how to design and/or improve green manufacturing systems as well as a roadmap for future quantitative research to better evaluate this new paradigm.     

我国再生锌行业二噁英污染有效控制技术探讨

分析了我国再生锌行业产生二噁英污染的概况,为我国再生锌行业二噁英污染控制提供了基本依据;在对我国再生锌行业二噁英污染节点分析基础上,阐述了我国再生锌行业二噁英污染的控制方法;并提出了再生锌二噁英污染控制的有效技术途径.     

基于PLC的MBR小型污水处理工艺的自动控制系统设计

本设计以沈阳市某污水处理及中水回用设施的控制系统为研究背景,结合污水处理工艺,探讨以日本三菱公司的FX2N系列的PLC在采用膜生物反应器(MBR)工艺的小型污水处理设施中的应用,重点阐述了系统的硬件构成及系统软件的设计思路,具有自动/手动两种工作模式,根据气水比比值以及自吸泵占空比确定鼓风机曝气启动时间,鼓风机自动定时...     

南水北调东线河流水环境污染特征及治理对策

利用2006～2009年例行监测数据以及2010年加密补充监测数据对复新河水环境状况进行了分析,通过对该地区污染源详细调查,利用等标污染负荷法对研究区域污染源状况进行了评价,在此基础上,对沙庄桥断面不达标原因进行了分析,并提出保障复新河水质达标的治理措施。结果表明:复新河流域水质超标现象显著,水质总体呈现先下降后上升趋势,原有治理措施达到一定的效果,但沙庄桥断面与稳定达Ⅲ类水标准仍有较大差距。研究区内污染负荷以畜禽粪尿的排放所造成的污染的贡献率最大,占36.55%,生活污水排放所造成的污染次之,占33.46%。流域内污染源是复新河水质受污染的主要影响因素,来水不畅,尾水无出路是断面不达标的首要原因。     

我国雾霾成因及防控策略研究

针对近年来我国雾霾频发的现象,通过对我国雾霾现状、污染物来源分析,阐明雾霾成因及危害,并从监测、评价、控制等角度阐述我国雾霾防控策略。     

天津市人为源VOCs排放现状及控制对策研究

根据2010年天津市公布的各类排放源活动水平数据,采用排放因子法,估算天津市人为源挥发性有机物排放量。结果表明:天津市人为源VOCs排放量中工业源贡献率最大,其次是流动源,生活源和生物质燃烧源贡献较小。根据天津市人为源挥发性有机物排放现状,提出VOCs控制对策及建议,为大气环境治理提供参考价值。     

沈阳市城市环境空气质量演替和PM_(2.5)的污染与达标措施探讨

沈阳市"九五"至"十一五"期间环境空气中的主要污染物为SO2、TSP、NO2,"十二五"以来,空气中PM2.5的污染凸显,形成以PM2.5为主要污染物的雾霾天气。通过科学规划、优化能源和产业结构及布局,实施燃煤和交通及扬尘污染综合整治,强化重污染行业控制及污染治理,推行区域大气污染联防联控,科学规划城市空间布局,开展科学技术及政策法规研究,加强环境空气质量监控与预报,强化公众参与等综合措施可以控制PM2.5的污染。     

Plasma arc welding: Process,sensing, control and modeling

This article introduces the basic principles of plasma arc welding (PAW) and provides a survey of the latest research and applications in the field. The PAW process is compared to gas tungsten arc welding, its process characteristics are listed, the classification is made, and two modes of operation in PAW, i.e., melt-in and keyhole, are explained. The keyhole mechanism and its influencing factors are introduced. The sensing and control methodologies of the PAW process are reviewed. The coupled behaviors of weld pool and keyhole, the heat transfer and fluid flow as well as three-dimensional modeling and simulation in PAW are discussed. Finally, a novel PAW process variant, the controlled pulse keyholing process and the corresponding experimental system are introduced.     

Work Content and Eye Discomfort in VDT Work

A questionnaire study of Swedish public employees with frequent and different types of VDT work (n = 2,025) was conducted. Eight different kinds of eye discomfort were examined, and an additive index was constructed. Eye discomfort was statistically related to aspects of work organization. The highest levels of discomfort were reported by computer-aided design (CAD), data entry, and word processing groups; groups with mixed VDT tasks displayed the lowest level of symptoms. Time spent at a VDT, low degree of work control, time pressure, and high pace of work were all associated with relatively high levels of eye discomfort. There was significant interaction between experience of stress and time spent at a VDT with respect to both the eye discomfort index and three specific symptoms (itching, gritty feeling, and dryness). Whereas dryness, smarting, and itching of the eyes seem most strongly related to work conditions, redness and watery eyes seem most weakly related.     

An evaluation of risk assessment framework for industrial accidents in India

Due to rapid industrialization, with high population density and constraints of land, it is expected that level of risks arising from the hazardous industries will increase in India in the coming decades. However, 30 years after the Bhopal accident (1984), except a few discrete regulations, there is as yet no integrated system for assessing and managing risks arising out of these hazardous industries in India. The gravity of aspects related to the management of industrial risk still remains crucially important. In particular, there is no standard guideline on risk analysis methodology, acceptability or tolerability criteria, nor is there an accident database or a risk reduction strategy for the areas where risk levels are already high. On top of this, there are technical and legislative gaps in the institutional framework to implement any of the above mentioned issues. With the backdrop of the Bhopal gas tragedy, the objective of this paper is therefore to evaluate the effectiveness of a comprehensive risk assessment framework for the emerging economy of India, in order to control and/or to reduce the risk level that exists. In this context, regulations and policies pertaining to industrial risk assessment were reviewed.