大体积钢筋混凝土拱形构件一次成型施工技术

为降低成本,缩短工期,对大体积钢筋混凝土拱形构件预制采用一次成型技术。阐述采用一次成型施工技术工艺原理。详细介绍施工操作要点。该工艺具有很高的社会和经济效益。     

Forecasting petrol demand and assessing the impact of selective strategies to reduce fuel consumption

Abstract

The use of fossil fuels in transportation is an important topic as a result of growing concerns over global warming. Automobile petrol demand has been of particular interest to researchers and policy-makers, given that the automobile is a major contributor to the enhanced greenhouse effect. This paper forecasts Australia's automobile petrol demand up to the year 2020 based on the best performing forecasting model selected out of eight models. In order to establish ways to reduce the demand for petrol, and the consequent by-product of reducing the amount of greenhouse gas emissions, we have estimated the impact on CO₂ for several potential policy instruments, using Transportation and Environment Strategy Impact Simulator (an integrated transport, land use and environmental strategy impact simulation programme). We find that a carbon tax of AU$0.50/kg can reduce automobile kilometres by 5.9%, resulting in reduced demand for petrol and a reduction in CO₂ of 1.5%.     

电控发动机节气门体故障分析

介绍了电控发动机节气门体的三种类型及特点。分析了各种节气门体的典型电路、信号特征和故障特征。     

广西甩挂运输发展对策研究

道路汽车甩挂运输在货物运输效率和节能减排效果上有显著的效益,正逐步得到社会各界的广泛关注。文章基于广西甩挂运输发展现状,预测分析广西发展道路甩挂运输的市场前景,并提出了广西发展甩挂运输的对策。     

A network-based dispatch model for evaluating the spatial and temporal effects of plug-in electric vehicle charging on GHG emissions

The well-to-wheel emissions associated with plug-in electric vehicles (PEVs) depend on the source of electricity and the current non-vehicle demand on the grid, thus must be evaluated via an integrated systems approach. We present a network-based dispatch model for the California electricity grid consisting of interconnected sub-regions to evaluate the impact of growing PEV demand on the existing power grid infrastructure system and energy resources. This model, built on a linear optimization framework, simultaneously considers spatiality and temporal dynamics of energy demand and supply. It was successfully benchmarked against historical data, and used to determine the regional impacts of several PEV charging profiles on the current electricity network. Average electricity carbon intensities for PEV charging range from 244 to 391 gCO₂e/kW h and marginal values range from 418 to 499 gCO₂e/kW h.     

船舶舱室的通风超压计算法

文章列举船舶舱室超压保护区通风建压涉及的各种因素,并从国内外文献资料、各国规范和实船经验中,分析总结推导出实用可行的针对各影响因素的船舶舱室通风超压计算法,对今后船舶密闭超压通风设计具有指导意义。     

基于事故树分析法的船舶LNG燃料加注火灾防控研究

文章采用事故树分析法,对船舶LNG燃料加注时可能引起火灾的事件进行了分析,提出了相应对策,为LNG动力船舶燃料加注的安全管理提供了参考。     

Research on Energy Efficiency Design Index for Sea-going LNG Carriers

This paper describes the characteristics of liquefied natural gas （LNG） carriers briefly. The LNG carrier includes power plant selection, vapor treatment, liquid cargo tank type, etc. Two parameters fuel substitution rate and recovery of boil of gas （BOG） volume to energy efficiency design index （EEDI） formula are added, and EEDI formula of LNG carriers is established based on ship EEDI formula. Then, based on steam turbine propulsion device of LNG carriers, mathematical models of LNG carriers＇ reference line value are established in this paper. By verification, the EEDI formula of LNG carriers described in this paper can provide a reference for LNG carrier EEDI calculation and green shipbuilding.     

散装货物运输中水尺计重研究

通过对水尺计重的原理及方法的研究,分析了在水尺计重过程中产生误差的主要原因;结合实践经验,阐述了作为承运人代表的船舶大副在水尺计重中应注意的一些事项,以免承运人在水尺计重这一工作中遭受不必要的损失。     

Assessing greenhouse gas and related air pollutant emissions from road traffic counts: A case study for Mauritius

The road transport sector is one of the major contributors of greenhouse gases and other air pollutants emissions. Regional emissions levels from road vehicles were investigated, in Mauritius, by applying a fuel-based approach. We estimated fuel consumption and air emissions based on traffic counts on the various types of classified roads at three different regional set ups, namely urban, semi urban and rural. The Relative Development Index (RDI), a composite index calculated from socio-economic and environmental indicators was used to classify regions. Our results show that the urban motorways were the most polluting due to heavy traffic. Some rural areas had important pollution levels as well. Our analysis of variance (ANOVA), however, showed little difference in emissions among road types and regions. The study can provide a simple tool for researchers in countries where data are very scarce, as is the case for many developing countries.