基于遗传算法对A公司生产线平衡的分析

在对A公司总装车间底盘装配生产线平衡现状进行分析的基础上,应用遗传算法对A公司总装车间底盘装配生产线进行分析改善,使得A公司总装车间底盘生产线瓶颈工序时间得到了有效地降低,生产线平衡率从76.3%提高到95.1%,生产线平衡损失率由原来的23.7%降低到4.9%,提高了生产线的平衡性。     

基于遗传算法对A公司生产线平衡的分析

在对A公司总装车间底盘装配生产线平衡现状进行分析的基础上,应用遗传算法对A公司总装车间底盘装配生产线进行分析改善,使得A公司总装车间底盘生产线瓶颈工序时间得到了有效地降低,生产线平衡率从76.3%提高到95.1%,生产线平衡损失率由原来的23.7%降低到4.9%,提高了生产线的平衡性。     

浅谈序间外委控制程序

汽车整车的生产是由冲压、焊装、涂装、总装四大车间完成,白车身是由多种冲压件、标准件、焊接小总成等多种金属件通过焊接工艺焊装而成,白车身经过涂装车间的喷涂、总装车间的装配后,完成整车生产。对规范四大车间的序间外委/转回的操作以及外委供应商选定的管理工作流程做出分析。     

再创新纪录 跃上新高度 北京奔驰月产超万辆

5月30日，北京奔驰公司在二工厂总装车间举行了“庆祝北京奔驰月产超万辆”的下线仪式。北京奔驰5月生产的第10000辆车驶下总装车间检测线，意味着北京奔驰自成立以来首次月产量超过10000辆，标志着北京奔驰生产经营跃上新的高度。     

汽车整车总装车间生产进度信息实时管理系统

在面向订单制造的生产模式下,借助信息化手段提高汽车总装车间生产进度信息透明化与实时化管理能力已成为汽车整车企业的重要发展趋势之一。文章结合MES(Manufacturing Execution System,MES,制造执行系统)思想,提出了一种汽车整车总装车间生产进度信息实时管理系统,研究了该系统的体系结构、功能结构、运行模式及其实现技术,并将其应用于一个汽车整车制造企业,取得了良好效果。     

汽车总装车间物流配送仿真及优化研究

本文以汽车工厂总装车间为研究背景,选取内饰线及零件的物流配送为研究对象,在建立总装车间基础仿真模型的基础上,建立物流配送模型,并对内饰线的线边物料缓存容量、物料呼叫提前期和配送车辆利用率进行仿真验证与优化研究,可有效优化物流配送过程中的资源配置。     

改进机械总装车间成本计算方法的尝试

机械制造企业总装车间的成本核算，在原材料成本的计算上比较繁重，是具有一定难度的。机械制造厂在二级核算制的情况下，原材料成本项目在总装车间一般反映为外购半成品和自制半成品两个项目。前者是指从厂外购入的直接用于装配的半成品；后者是指本厂其它工序加工完成的直接用于装配的半成品。无论是外购半成品还是自制半成品，反映在总装车间都具有两个特点：一是品种多、数量大；二是领入总装车间后即直接进入装配线，车间不另设库保管。这两个特点使得总装车间的原材料成本项目在计算上具有较大的难度，其主要问题表现在两个方面：     

浅谈6376制动液储液壶口漏油原因分析及解决方法

文章主要介绍6376车在上汽通用五菱东部总装车间进行负压加注制动液时,制动液从储液壶口泄漏的现象,并通过原因分析和采用新方法来解决制动液泄漏这一难题,从而满足了现场生产的要求,同时解决了由于制动液泄漏造成的一系列成本浪费和员工可能滑倒的安全隐患.     

浅谈6376制动液黼口漏油原因分析及解决方法

文章主要介绍6376车在上汽通用五菱东部总装车间进行负压加注制动液时，制动液从储液壶口泄漏的现象，并通过原因分析和采用新方法来解决制动液泄漏这一难题。从而满足了现场生产的要求，同时解决了由于制动液泄漏造成的一系列成本浪费和员工可能滑倒的安全隐患。     

WH公司生产线平衡研究

生产线平衡研究一直以来都是制造业生产车间提高生产效率的一项重要课题。文章以WH公司燃气采暖热水器产品生产线为研究背景,通过改进车间布局将总装流水线和离散部装生产区进行重组,使该生产线平衡率由改善前的65%提升到90.1%,从而达到改善效果。     

我国轿车性价比评价模型

我国轿车市场日渐成熟,消费者购车更加理性,希望购买到性价比高的车子。目前市场上关于轿车性价比的评价多为定性的描述。运用价值工程理论构建出我国家用轿车性价比的评价模型,对家用轿车进行定量描述,期望能为消费者的购车提供一定的参考。     

Autoverkopen en autopark in Nederland, 1950–1970

Summary  This is a study of the demand for the ownership of new or firsthand cars, i.e. the demand of 'first owners' who habitually buy new cars which are then traded in long before they are obsolescent. Upon combining the evidence of various surveys with time-series for 1950-64 it is found that this ownership has an income elasticity of 2 and a price elasticity of – 1.25 in respect of the constant-quality index of new car prices earlier provided. On the average new cars are traded in after three years so that roughly one third of the existing stock is replaced every year. These values together determine an equation for purchases of new cars which accurately predicts new registrations in 1965 and 1966. Projections for the years 1967-70 are provided.
In the model employed the total number of cars (including used cars) is determined by the active demand exerted by 'first owners' on one hand and by the hitherto fairly constant scrappage rates on the other. Projections of the overall ownership rate can therefore be derived from the forecasts of new registrations. The ownership rate will approach 80% around 1970, and it is likely that at that stage the current scrappage rates will cease to apply in view of the greater predilection for comparatively younger cars.     

Autoverkopen en autopark in Nederland, 1950–1970

Summary This is a study of the demand for the ownership of new or firsthand cars, i.e. the demand of ‘first owners’ who habitually buy new cars which are then traded in long before they are obsolescent. Upon combining the evidence of various surveys with time-series for 1950-64 it is found that this ownership has an income elasticity of 2 and a price elasticity of – 1.25 in respect of the constant-quality index of new car prices earlier provided. On the average new cars are traded in after three years so that roughly one third of the existing stock is replaced every year. These values together determine an equation for purchases of new cars which accurately predicts new registrations in 1965 and 1966. Projections for the years 1967-70 are provided. In the model employed the total number of cars (including used cars) is determined by the active demand exerted by ‘first owners’ on one hand and by the hitherto fairly constant scrappage rates on the other. Projections of the overall ownership rate can therefore be derived from the forecasts of new registrations. The ownership rate will approach 80% around 1970, and it is likely that at that stage the current scrappage rates will cease to apply in view of the greater predilection for comparatively younger cars.     

An econometric model of new-car demand in the UK

An econometric model which explains the demand for new cars is specified and estimated, and good empirical results are obtained which imply that the model should provide reliable forecasts of new-car demand. Furthermore, these forecasts are likely to be greatly superior to those generated by simple naive models.     

An empirical analysis of effects of gasoline price change on transportation behavior in Japan,with consideration of regional differences

This empirically analyzes the effect of gasoline price change on various aspects of surface transport behavior comprehensively, with consideration of regional differences as to whether or not the region includes a major metropolitan agglomeration area (hereafter, “megalopolis”), by means of carefully arranging yearly time-series data from fiscal 1987 to fiscal 2008 in Japan. The aim is to look at common as well as different effects among regions and to draw policy implications relating to fuel price, as well as to fuel tax, towards developing a low-carbon transport system, which are applicable to other countries including emerging countries where a demographic disparity between megalopolis areas and rural areas might be increasing. The methodology includes the multiple regression models complemented by the 1st order auto-regressive models of error terms, where the elasticities of gasoline price and those of income regarding usage of personal automobiles, of public transport and of passenger railways with or without periodic tickets, and fuel consumption on cars, as well as ownership of various types of cars, are estimated for individual gross-regions. In both gross-regions, higher gasoline prices are commonly shown to be related to lower ownership of larger private passenger cars, higher ownership of light cars, lower ownership of the total private passenger cars, lower passenger-km per capita in cars, lower fuel consumption on cars and higher transit ridership. The result suggests general automobile-fuel-price policy implications, the extent of which is differentiated by spatial characteristics, and estimates the adverse effect of the possible abolition of the provisional gasoline tax rate on the emissions in both gross-regions. The application of result is also tried in exploring effect of other policy measures such as expressway tolls.     

Coopetitive games for environmental sustainability: Climate change and decision global policies

In this work, we propose and analyze a coopetitive model for the Climate Change environmental sustainability: a global duopoly type game structure, involving a generic type of green technological good. Our model allows to select certain strategy profile solutions within a continuous horizon of possible global scenarios, in the context of the Paris agreement COP21 and after Trump’s decision to abandon the agreement itself. More specifically, we construct a parametric coopetitive game with two great actors, US and the group of countries which still agree to COP21. The two actors of our duopoly game compete on the global market by producing and selling green technological goods (for example: electric cars, electric airplanes, hydrogen cars, solar panels, low impact batteries for smart houses, electric cars or self phones, and so on). Our multi-dimensional coopetitive model suggests possible cooperative strategies in order to improve the efficiency and strength of the actions enforced by the countries to mitigate the Climate Change catastrophic risk at the level of its causes and effects.     

我国废旧汽车回收模式选择探析

废旧汽车回收模式影响回收效率。文章归纳总结了废旧汽车回收模式类型,分析了各种回收模式的利与弊,从经济、管理、技术方面阐述了影响回收模式选择的因素,并建立了回收模式评价指标体系,对我国建立有效、快捷的废旧汽车回收模式具有指导意义。     

Is econometrics useful for private policy making? A case study of replacement policy at an auto rental company

The goal of this paper is to illustrate the potential usefulness of econometrics as a tool to assist private policy makers. We provide a case study and detailed econometric analysis of the automobile replacement policy adopted by a large car rental company. Unlike public policy making–where the benefits from using econometric models and “science-based” approaches to policy making are hard to quantify because the outcomes of interest are typically subjective quantities such as “social welfare”–in the case of firms there is an objective, easily quantifiable criterion for judging whether policy A is better than policy B: profits. We introduce and estimate an econometric model of the rental histories of individual cars in the company’s fleet. Via stochastic simulations, we show that the model provides a good approximation to the company’s actual operations. In particular, the econometric model is able to reproduce the extraordinarily high rates of return that the company obtains on its rental cars, with average internal rates of return between purchase and sale of approximately 50%. However, the econometric model can simulate outcomes under a range of counterfactual vehicle replacement policies. We use the econometric model to simulate the profitability of an alternative replacement policy under pessimistic assumptions about the rate maintenance costs would increase and rental rates would have to be decreased if the company were to keep its rental cars longer than it does under the status quo. Depending on the vehicle type, we find that the company’s expected discounted profits would be between 6% to over 140% higher under the suggested alternative operating strategy where vehicles are kept longer and rental rates of older vehicles are discounted to induce customers to rent them. The company found this analysis to be sufficiently convincing that it undertook an experiment to verify the predictions of the econometric model.     

云南报废汽车逆向物流体系构建研究

通过界定逆向物流以及报废汽车逆向物流的概念及类型,从国家、企业和社会三方面说明云南构建报废汽车逆向物流体系的必要性。然后从云南该体系的发展现状着手,找出不足。最后具体结合云南报废汽车逆向物流产业的特点,对构建云南报废汽车逆向物流体系提出几点建设性意见。     

A bathtub model of downtown traffic congestion

In standard economic models of traffic congestion, traffic flow does not fall under heavily congested conditions. But this is counter to experience, especially in the downtown areas of major cities during rush hour. This paper analyzes a bathtub model of downtown rush-hour traffic congestion that builds on ideas put forward by William Vickrey. Water flowing into the bathtub corresponds to cars entering the traffic stream, water flowing out of the bathtub to cars exiting from it, and the height of water in the bathtub to traffic density. Velocity is negatively related to density, and outflow is proportional to the product of density and velocity. Above a critical density, outflow falls as density increases (traffic jam situations). When demand is high relative to capacity, applying an optimal time-varying toll generates benefits that may be considerably larger than those obtained from standard models and that exceed the toll revenue collected.