A comparison between the life cycle cost of gravel and of bituminous surfacing options for feeder roads in Ghana

Feeder roads, which constitute a key component of rural transport infrastructure, play a vital role in rural development, but only 5% of the total feeder road network in Ghana has bituminous seal surfacing. The remaining 95% have either gravel or earth surfacing. However, gravel surfacing (G-S) is known to deteriorate rather rapidly necessitating expensive frequent maintenance while bituminous surfacing offers a more durable surfacing. Various life cycle cost studies have suggested that even though G-S may have lower initial construction costs, they tend to have higher life cycle costs than bituminous seal surfaced ones. However, since most of these studies are based on ideal maintenance practices, their conclusions do not reflect actual field conditions. This study seeks therefore to compare the life cycle cost of G-S with that of bituminous seal surfacing options for engineered feeder roads in Ghana using actual cost data. Data were collected from eight feeder road projects with G-S and a similar number with bituminous surfacing from six regions of Ghana completed between 2010 and 2013. The life cycle cost for each road was computed using a discount rate of 12% and an inflation rate of 15% over an analysis period of 21 years. The results for G-S are then compared with those for single bituminous seal surfacing and for double bituminous seal surfacing. The results are further compared with those from trial sections of an experimental study of Otta seal surfacing using natural gravel and using crushed rock as aggregates. The results suggest that based on the high initial construction costs of bituminous seal surfacing and actual low maintenance intervention practices, G-S remain the least cost option. The study recommends the need for alternative surfacing technology that does not involve bitumen.     

产品生命周期成本概念及分析方法

随着人们成本意识的增强,生命周期成本日益引起设计者和用户的重视。对产品生命周期和产品生命周期成本概念进行了论述,介绍了参数模型、类推模型和详细模型3种生命周期成本分析模型,最后以某厂计划购买自动包装生产线为例,说明如何利用生命周期成本概念进行投资决策分析。     

A comprehensive life cycle costs analysis of in-place recycling and conventional pavement construction and maintenance practices

Recent studies based on Life Cycle Assessment (LCA) have highlighted the potential of in-place recycling techniques to enhance the sustainability of agency pavement management decisions for asphalt pavements. However, a solution which an LCA finds environmentally advantageous might not be preferred over another which is technically equivalent, if it is not economically competitive. In this context, it is necessary to evaluate the economic costs of such alternatives taking into account the perspective of the main stakeholders who interact with a pavement system throughout its life cycle. This paper presents a comprehensive pavement life cycle costs (LCC) model that accounts for the different categories of costs incurred by highway agencies and road users in every phase of the pavement life cycle. The results of the application of the pavement LCC model to a specific highway rehabilitation project in the state of Virginia showed that in-place recycling practices are beneficial for both highway agencies and road users.     

Reliability-based optimization of direct and indirect LCC of RC bridge elements under coupled fatigue-corrosion deterioration processes

An optimal bridge design should minimize the life cycle cost (LCC) of the structure without compromising its safety. Various cost components need to be evaluated when assessing the life cycle cost of a reinforced concrete bridge. When the structure is subjected to performance degradation due to aging, the probabilistic modeling of degradation is required. In this paper, the reliability-based design optimization RBDO is performed on the life cycle cost of the structure subject to deterioration processes of fatigue and corrosion. This paper advances the state of the art by: considering the coupled corrosion fatigue model in the design optimization and by developing a new approach to evaluate the user delay costs on a bridge, based on direct and indirect costs related to degradation and failure. Also, a sensitivity analysis of optimal costs and design variables is performed. The improved life cycle cost analysis presented herein can be applied to select the optimal design of reinforced concrete bridge elements, by minimizing both agency and bridge user costs, while providing the required safety along the structure lifetime, taking into account the most severe degradation processes.     

Mechanistic-empirical methodology for the selection of cost-effective rehabilitation strategy for flexible pavements

A well-planned rehabilitation approach helps agencies to optimise the allocation of annual investment in pavement rehabilitation programs. Currently, many agencies are struggling with the selection of an optimal time-based and cost-effective rehabilitation solution to address the long-term needs of pavements. This study offers the use of a mechanistic-empirical methodology to develop a series of time-based rehabilitation strategies for high traffic volume flexible pavements located in Oklahoma. Six different pavement family groups are identified in the state, and comprehensive evaluation of existing pavements are conducted through analysis of falling weight deflectometer data and performance measures available in Oklahoma Pavement Management System database. The inadequacy of performance measures to fully characterise the condition of existing pavements are indicated, and damage factor determined from FWD data are suggested as trigger factor to select rehabilitation candidates. Three levels of rehabilitation activities including light, medium and heavy are considered as potential alternatives for rehabilitation candidates. A mechanistic-empirical methodology is employed to obtain an estimate of the performance of rehabilitation and extension in service lives of pavements. Also, an assessment output matrix is developed, which can be served as a supplemental tool to help the decision-makers in the highway agency with the rehabilitation related decision-making process. Cost-effectiveness of rehabilitation alternatives is determined through life cycle cost analysis, and three time-based renewal solutions are developed for pavement family groups that are in need of rehabilitation.     

An integrated approach to evaluating conceptual design alternatives in a new product development environment

As many companies have demonstrated over time, a conceptual design for a new product contributes greatly to an improvement in competitiveness, because it permits a reduction of costs, an increase in quality, and, often, a shortening of the time necessary to get the product on the market. That is why the evaluation of conceptual design alternatives created in a new product development (NPD) environment has long been very vital and a critical point for the future success of companies in fast-growing markets. These alternatives can be evaluated using the analytic hierarchy process (AHP), one of the most commonly used multiple criteria decision making (MCDM) techniques. This technique is used to reduce the number of conceptual design alternatives after ranking them using the scores obtained from the process. Furthermore, another technique, simulation analysis integrated with the AHP, is also used to help decision makers (product engineers or managers) perform economic analyses of the AHP's high-score alternatives using data from the generated simulation model of a real-life manufacturing system in which the final alternative is produced. In short, the objectives of this research are: first, to use the AHP technique to evaluate conceptual design alternatives in a NPD environment; second, to use a simulation generator integrated with this technique in order to perform economic analyses for the AHP's high-score alternatives. Finally, the results of both techniques, simulation and AHP, are used in a benefit/cost (B/C) analysis to reach a final decision on the conceptual design alternatives.     

基于全寿命周期费用分析法的风管系统的选择

针对目前国内还没有一种有效的方法用于选择和评价风管系统的现状,提出采用全寿命周期费用分析法来选择和评价风管系统,并在实际工程中,采用该方法比较和分析国内4种常见风管系统的一次性投资、能耗费和维护费,重点对各风管的全寿命周期费用进行评估,认为酚醛铝箔复合风管的费用最低,是一种值得推广的风管系统。     

工业节能降耗的全生命周期成本研究

基于节能降耗与可持续发展,将全生命周期成本分析方法用于工业节能降耗的研究,对工业产品的全生命周期成本及能耗进行了分析．在利用LCC方法分析工艺全生命周期成本的同时,还考虑了影响能源消耗的成本因素．力图在兼顾节能降耗的同时,考虑企业成本最小化与利益最大化,为有效指导工业节能降耗生产、合理选择工艺设施提供了新的思路,也为设备规划和选型、计算设备的经济寿命、管理控制设备投资以及项目的方案论证等提供方法和工具．     

Levelized costs of the energy chains of new energy vehicles targeted at carbon neutrality in China

The diffusion of new energy vehicles (NEVs), such as battery electric vehicles (BEVs) and fuel cell vehicles (FCVs), is critical to the transportation sector’s deep decarbonization. The cost of energy chains is an important factor in the diffusion of NEVs. Although researchers have addressed the technological learning effect of NEVs and the life cycle emissions associated with the diffusion of NEVs, little work has been conducted to analyze the life cycle costs of different energy chains associated with different NEVs in consideration of technological learning potential. Thus, relevant information on investment remains insufficient to promote the deployment of NEVs. This study proposes a systematic framework that includes various (competing or coordinated) energy chains of NEVs formed with different technologies of power generation and transmission, hydrogen production and transportation, power-to-liquid fuel, and fuel transportation. The levelized costs of three typical carbon-neutral energy chains are investigated using the life cycle cost model and considering the technological learning effect. Results show that the current well-to-pump levelized costs of the energy chains in China for BEVs, FCVs, and internal combustion engine vehicles (ICEVs) are approximately 3.60, 4.31, and 2.21 yuan/GJ, respectively, and the well-to-wheel levelized costs are 4.50, 6.15, and 7.51 yuan/GJ, respectively. These costs primarily include raw material costs, and they vary greatly for BEVs and FCVs from resource and consumer costs. In consideration of the technological learning effect, the energy chains’ well-to-wheel levelized costs are expected to decrease by 24.82% for BEVs, 27.12% for FCVs, and 19.25% for ICEVs by 2060. This work also summarizes policy recommendations on developing energy chains to promote the diffusion of NEVs in China.     

Tradeoff Analysis for RMS of Equipment Based Operation Availability and Life Cycle Cost

Reliability, maintainability, supportability (RMS) are the important performance indexes of equipment, which affect not only the availability, but also the life cycle cost (LCC) of the equipment. First discussed is the qualitative relation between reliability and LCC and the costs which may be used to enhance the reliability. Secondly, the factors that affect the maintainability are summarized, and if maintainability is advanced, the trend of the LCC is depicted. Thirdly, the qualitative relation between th...     

Eco‐efficient Value Creation: An Alternative Perspective on Packaging and Sustainability

The classical sustainability perspective on packaging is to reduce the environmental impact or eco‐burden of the packaging, using life cycle assessment to evaluate different design alternatives. Simultaneously, the classical marketing perspective on packaging is to generate value through differentiation, for instance, by providing additional convenience. These two perspectives often conflict. In business reality, there is currently no established method to deal with these conflicts. Life cycle assessment is methodologically incapable of incorporating the difference in convenience. This article uses the eco‐costs/value ratio (EVR), as a method for dealing with the environmental assessment of packaging design alternatives with such unequal ‘soft’ functionality. The article reviews the current debate on packaging and sustainability, highlighting some of the shortcomings of the methods currently applied. Subsequently, the EVR model is introduced and applied to five examples. These examples consist of pairs of products, where the product, the amount, the brand and the retail outlet are identical and only the packaging design and the value differ. The examples illustrate how the EVR model fits better to design decision making in business reality than classical life cycle assessment. Copyright © 2012 John Wiley & Sons, Ltd.     

Materials Selection of Marine Seawater Pipelines Based on Life Cycle Costing

Marine seawater pipelines can be manufactured from different materials that vary in their purchase costs and lifetimes, thus presenting a challenge when selecting proper materials for a particular project. To solve this problem, a life cycle cost model for marine seawater pipelines was developed after identifying key corrosion features of pipeline materials. An offshore oilfield ship was used as a case study to compare the differences in the life cycle costs of marine seawater pipelines made of plain-carbon steel, seamless galvanized steel, stainless steel, stainless galvanized steel, and copper-nickel alloy. It was found that the seamless galvanized steel pipeline was a robust and economic choice for marine seawater pipelines for the offshore oilfield ship. The results showed that the proposed life cycle cost model was efficient and could be used in the design phase of ships.     

Methodology for fitting and updating predictive accident models with trend

Reliable predictive accident models (PAMs) (also referred to as Safety Performance Functions (SPFs)) have a variety of important uses in traffic safety research and practice. They are used to help identify sites in need of remedial treatment, in the design of transport schemes to assess safety implications, and to estimate the effectiveness of remedial treatments. The PAMs currently in use in the UK are now quite old; the data used in their development was gathered up to 30 years ago. Many changes have occurred over that period in road and vehicle design, in road safety campaigns and legislation, and the national accident rate has fallen substantially. It seems unlikely that these ageing models can be relied upon to provide accurate and reliable predictions of accident frequencies on the roads today. This paper addresses a number of methodological issues that arise in seeking practical and efficient ways to update PAMs, whether by re-calibration or by re-fitting. Models for accidents on rural single carriageway roads have been chosen to illustrate these issues, including the choice of distributional assumption for overdispersion, the choice of goodness of fit measures, questions of independence between observations in different years, and between links on the same scheme, the estimation of trends in the models, the uncertainty of predictions, as well as considerations about the most efficient and convenient ways to fit the required models.     

共享单车生命周期评价对比分析

目的 对共享单车的环境影响进行对比分析,从设计的角度提出改进建议,旨在弥补作为可持续产品服务系统的共享单车,在产品可持续上的欠缺,让共享单车更可持续。方法 在生命周期评价理论的框架指导下,对ofo 4.0与摩拜经典版2.0的环境影响进行对比分析,采用敏感性分析方法,分析共享单车生命周期对影响因素变化的敏感性。结果 提供等量的出行服务,ofo 4.0比摩拜经典版2.0对环境产生的影响更大,共享单车生命周期的环境影响对使用寿命最敏感。结论 延长使用寿命可以有效减少共享单车对环境的影响,具体建议是,在设计过程中应注意节材,在保证性能的情况下,优先使用环境影响低且耐用的材料;注意共享单车的拆卸回收性以及面向用户的不易拆卸性;通过面向服务的模块化设计,实现单车的快速更新换代和低成本的个性化服务。     

空调能效比发展趋势的研究

分析当前国内外空调能效标准的现状,指出我国空调能效比仍有较大提升空间.从理论上分析空调能效比的极限,同时对提高能效比的措施所影响到的生命周期成本进行分析,明确空调器不能一味追求高能效比,而应将生命周期成本作为衡量产品的尺度,寻找最佳的生命周期成本,这样即可以节能又能够减少消费者投资.     

Life cycle assessment framework for asphalt pavements: methods to calculate and allocate energy of binder and additives

The construction, maintenance and disposal of asphalt pavements may lead to considerable environmental impacts, in terms of energy use and emissions during the life of the pavement. In order to enable quantification of the potential environmental impacts due to construction, maintenance and disposal of roads, an open life cycle assessment (LCA) framework for the asphalt pavements is presented in this paper. Emphasis was placed on the calculation and allocation of energy used for binder and additives at the project level. It was concluded from this study that when progressing from LCA to its corresponding life cycle cost, the feedstock energy of the binder becomes highly relevant as the cost of the binder will be reflected in its alternative value as fuel. Regarding additives like wax, a framework for energy allocation was suggested. The suggested project level LCA framework was demonstrated in a limited case study of a Swedish asphalt pavement. It was concluded that the asphalt production and transporting materials were the two most energy-consuming processes, emitting most greenhouse gases depending on the fuel type and electricity mix.     

Aircraft Combat Survivability Estimation and Synthetic Tradeoff Methods

A new concept is proposed that susceptibility, vulnerability, reliability, maintainability and supportability should be essential factors of aircraft combat survivability. A weight coefficient method and a synthetic method are proposed to estimate aircraft combat survivability based on the essential factors. Considering that it takes cost to enhance aircraft combat survivability, a synthetic tradeoff model between aircraft combat survivability and life cycle cost is built. The aircraft combat survivability estimation methods and synthetic tradeoff with a life cycle cost model will be helpful for aircraft combat survivability design and enhancement.     

A risk-based optimisation for pavement preventative maintenance with probabilistic LCCA: a Chinese case

Compared to major structural repair or even replacement, preventative preservation of in-service pavements has been more popular in engineering practices, but recently, pavement preventative maintenance (PPM) has become more complex in China as the competition for pavement preservation funds has grown and the need to justify decisions has increased. Therefore, the life cycle cost analysis (LCCA) has increasingly attracted attention from transportation agencies. However, most of previous studies were conducted deterministically or only focused on a single factor, while PPM is apparently affected by many potential sources of uncertainty. The risk-based analysis to investigate potential risks and combined effects of multiple factors is a necessary component of PPM. This paper aims at presenting a risk-based PPM with the probabilistic LCCA for a Chinese highway case. Major analysis variables of different range are examined to probe risks of different scenarios, investigate combined effects of multiple variables and identify an optimal preservation strategy.     

面向成本的产品包装设计

面向成本的设计（design for cost,DFC)是指在满足用户需求的前提下，在尽可能降低产品成本的设计过程中所提供的技术支持。面向成本的产品包装设计是DFC在产品包装设计领域的应用，其主要特点是在包装研制开发中，将成本作为一个与产品包装功能性、可加工性等要求同等重要的参数给予确定。文中分析了主要包装物（玻璃瓶、塑料瓶、铝罐、纸盒）在其全生命周期内的成本构成，并在此基础上提出了产品包装成本的估算框架。     

The Role of Household Food Waste in Comparing Environmental Impacts of Packaging Alternatives

This paper examines the environmental impacts of food waste and the influence that packaging alternatives can have on causing food waste. This paper presents the results of three life cycle assessment case studies on packed food products. The life cycle assessments were conducted for ham, dark bread and Soygurt drink (fermented soy‐based drink). In each case study, the environmental impacts of the products were assessed with different assumptions about the packaging sizes and alternative materials. The studies especially considered the environmental impacts resulting from food waste generated by consumers as a function of the variable packaging options. The food waste of other parts of the production chain of the studied products was also taken into account. A consumer survey was carried out to estimate the amounts of product waste generated in Finnish households connected to the three investigated products. The environmental impacts of the food products, household food waste and packaging were modelled by scenarios with varying rates of household food waste and different waste management options. The results indicated that the significance of the production and post‐consumer life of packaging was relatively low for climate change, eutrophication and acidification, in comparison with the production chain of the ham, dark bread and Soygurt. According to the results, packaging solutions that minimize the waste generation in households as well as in distribution and retail will lead to the lowest environmental impacts of the entire product‐packaging chain. Therefore, it is important to design packages that protect the food properly and allow the consumer to use the product fully. Copyright © 2013 John Wiley & Sons, Ltd.