Three-Dimensional Lifting Model For Non-Homogeneous Loads

A 3-dimensional model and analysis methodology is suggested for treating lifting tasks when unbalanced loads are involved. The paper describes the biomechanical equations that are coupled with the worker’s posture geometry, to address a practical problem of non-symmetric lifting. The analysis has a dominant biomechanical modeling scope, as it contains a breakdown of the internal lifting forces resulting from posture and external loads acting on the body. The load model represents the acting forces due to unbalanced lifting, which is commonly found in industrial situations. The suggested model allows the user to simulate the influence of the practical load distribution, aiding safe design of a lifting job.     

A Whole Body Postural Loading Simulation and Assessment Model for Workplace Analysis and Design

Abstract

This study reports on the development and validation of a new computer model for simulating human postures at work, and assessing the reaction forces and bending moments in 43 human articulation joints. The proposed model estimates the intradiscal pressure in the vertebral column in response to external loading forces encountered during human interactions with work objects or processes. The model was implemented in a self-contained interactive software package. The simulation results compare favorably with the reported experimental data, and provide reasonable confidence in the quality of the model. Its characteristics and its applications in evaluating physical task performance are also discussed     

岳阳市南湖水体富营养化趋势研究

监测了湖南岳阳市南湖水体富营养化指标和纳污状况,分析了南湖水体富营养化趋势,探讨了人工水产养殖对南湖水体富营养化的影响。     

Shopping studies for regional planning

This paper is based on a shopping study carried out by the Department of Geography, University of Utrecht, during 1983. It is concerned with retail planning research for larger regions and starts with a state of the art review of retail planning research in the Netherlands. The aim, in developing a new research strategy, was to reduce time and costs through using computer facilit es for both data handling and data collection. There is discussion of methodology and some outcomes to demonstrate the possibilities of the strategy.     

Aerial photographs: their use in guiding pilgrims and pointers for developing countries

The problems faced by authorities in Saudi Arabia in managing the large numbers of pilgrims visiting Muna during a brief period each year has led to experiments with aerial photography and computer techniques. This paper describes briefly the new method initiated in 1981 emphasising the remarkably short time available for information assembly and interpretation and concludes with pointers towards the development of the techniques for Third World urbanisation studies.     

大型气候实验室高低温模拟系统关键技术研究

目的突破关键技术,获得适用于大型气候实验室的高低温环境模拟系统方案。方法通过分析大型气候实验室载冷/载热系统和空气处理系统的工作原理和工作模式,指出高低温环境模拟系统在可能遇到的极端温度下存在的安全风险,从低温试验工况推断出换热器结霜的必然性。根据载冷剂物性设计规避系统安全风险和融霜的技术方案。结果在AS-6系统和CH2CL2系统的二次循环中设计了充注/排空功能,规避了载冷/载热系统的安全风险。设计了内外融霜结合的融霜方案,进行换热器融霜。结论试验和工程应用证明,通过增加载冷剂充注/排空方案和换热器融霜方案完善的大型气候实验室的高低温环境模拟系统方案合理可行,采用的关键技术可以指导类似系统设计。     

Epidemiological and biomechanical evaluation of airline baggage handling

Objectives. Musculoskeletal disorders (MSDs) are prevalent among airline baggage handlers due to manual materials handling. In this study, the Nordic musculoskeletal questionnaire (NMQ), the revised National Institute for Occupational Safety and Health (NIOSH) lifting equation, and the University of Michigan 3D Static Strength Prediction Program? (3DSSPP) were used to analyze MSDs among baggage handlers. Methods. The NMQ was filled out by 209 baggage handlers and 46 arbitrarily selected baggage handlers were evaluated using the NIOSH method and 3DSSPP. Results. The obtained results showed that the most common MSDs occurred in the lower back region. The next risky regions included knees, neck, and upper back, respectively. The NIOSH results confirmed that the subjects lifted loads heavier than the permitted limit and their lifting postures were inappropriate. The results of the 3DSSPP also indicated that compression forces exceeded the NIOSH limit in these awkward postures. Conclusions. Relying on this study, holding compulsory ergonomic lifting training courses could be proposed for workers and regulations adjusting an upper limit for maximum baggage weight must be also enacted in order to improve occupational health and prevent the prevalence of increasing MSDs.     

基于污泥转移的SBR工艺污泥沉降性能研究

具有污泥转移功能的SBR工艺是利用SBR工艺的间歇运行特性,通过污泥回流的方式在并联运行的SBR间实现活性污泥的转移,使各SBR反应器中反应阶段污泥量增加,沉淀撇水阶段减少,从而提高系统除污效能和处理能力。以某低浓度城市污水为水源,进行了中试研究。分析了在不同污泥转移量下系统中污泥的沉降界面、污泥指数等关系,考察了污泥转移对SBR处理能力的影响。试验结果表明:污泥转移可改善污泥沉降性能,30%的污泥回流比下反应器中污泥的SVI值由无污泥转移时的140降低为93左右;采用30%的污泥回流比进行污泥转移可将传统SBR工艺处理能力提高近1/2。     

NIOSH手工提举方程在缸盖搬运中的应用

为了平衡操作人员的精力和体力,在保证人安全的前提下,提高生产力。采用NIOSH（National Institute of Occupational Safety and Health）提举方程对机加工车间缸盖搬运上线工位进行人机工程安全评估,通过对操作工作业的水平距离（H）、垂直距离（V）、提升距离（D）以及频率（F）进行研究,并对修订版NIOSH提举方程的重量常量与高度系数进行了修正。结果表明,经过合理调整四大参数,可在不设起吊、机器人等设备的情况下,保证人的身心健康,节约成本,提高人的工作效能。     

西安市某工业园夏季VOCs浓度特征及O3、SOA生成潜势

2020年7月30日—10月10日对西安市某工业园区大气中的70种VOCs开展了为期73 d的VOCs手工采样监测,分析了上、下风向2个点位VOCs浓度组成特征、O₃生成潜势和SOA生成潜势,并运用PMF进一步分析该区域VOCs的主要来源。结果显示：监测期间工业园区平均VOCs浓度为203.50 μg/m³,以甲醛和乙醛为主的醛酮类（148.37 μg/m³）是主要污染物,占TVOC浓度的57%~84%,其次是烷烃。通过上、下风向VOCs成分比较发现,醛酮类为高污染时段特征污染物,工业园区平均OFP为969.66 μg/m³,醛酮类对O₃生成的贡献最大,占TOFP的80%~97%,其次是烯烃。工业园区平均SOAFP为0.50 μg/m³,芳香烃对SOA生成的贡献最大,占TSOAFP的48%~98%,其次是烷烃。PMF源解析得到5个因子,分别为工业源、溶剂涂料、燃烧源、移动源及其他源,贡献率分别占35.2%、20.4%、18.3%、12.8%、13.3%,解析显示该区域受到下风向电子产业影响较大。