scholarly journals A New Multi Echelon Repair Network Model with Multiple Upstream Locations for Level of Repair Analysis Problem

2021 ◽  
Vol 71 (6) ◽  
pp. 762-771
Author(s):  
İsmail Bıçakcı ◽  
Yusuf Tansel İç ◽  
Esra Karasakal ◽  
Berna Dengiz
Keyword(s):  
Life Cycle ◽  
Life Cycles ◽  
Life Cycle Costs ◽  
Capital Goods ◽  
Upper Echelon ◽  
Proposed Model ◽  
Benchmark Instances ◽  
Level Of Repair Analysis ◽  
Total Life ◽  
Support Phase

Level of repair analysis (LORA) determines (1) the best decision during a malfunction of each product component; (2) the location in the repair network to perform the decision and (3) the quantity of required resources in each facility. Capital goods have long life cycles and their total life cycle costs are extremely high. LORA, which can be done repeatedly during the life cycle of the product, both at design and product support phase, plays an important role in minimising the total life cycle costs of capital goods. It is mostly applied to systems that operate in different geographical areas and deployed in different regions, which include different subsystems with special technology and expertise, and have a complex product structure. In this study, we propose a new mathematical model to the LORA problem, which is more comprehensive and flexible than the other pure LORA models in the literature. The proposed model uses the multiple upstream approach that allows the transfer of the components from a location in the lower echelon to the predefined locations in the upper echelon and determines the material movement paths between each facility, defining the facilities’ locations in the repair network. The performance of the proposed model is tested on benchmark instances and the results are compared with the single upstream model. Computational experiments show that the proposed model is more effective than the single upstream model and reduces the total life cycle costs by 4.85% on average, which is an enormous cost saving when total life cycle costs of capital goods are considered.

scholarly journals Energy Consumption and Life Cycle Costs of Overhead Catenary Heavy-Duty Trucks for Long-Haul Transportation

Energies ◽  
2018 ◽  
Vol 11 (12) ◽  
pp. 3446 ◽  
Author(s):  
Ivan Mareev ◽  
Dirk Sauer
Keyword(s):  
Life Cycle ◽  
Energy Consumption ◽  
Power System ◽  
Energy Supply ◽  
Life Cycle Costs ◽  
Heavy Duty ◽  
Energy Consumptions ◽  
The Cost ◽  
Total Life

The overhead catenary truck is an interesting technology for long-haul transportation with heavy-duty trucks because it can combine the advantage of energy supply via catenary while driving and the flexibility of a battery truck on routes without catenary using the traction battery. This study investigates the energy consumptions of overhead catenary trucks on German highways and considers different configurations for the traction battery and catenary power system. Afterwards the life cycle costs of overhead catenary trucks are calculated for a specified long-haul transportation scenario and the results are compared to battery electric truck and diesel truck using the findings of a previous study by the authors. The energy consumption of the considered overhead catenary trucks is approximately equal to that of a battery electric truck but only about a half of the equivalent energy consumption of a conventional diesel truck. According to the cost assumptions in this study, the total life cycle costs of overhead catenary trucks can be in the range of the conventional diesel truck, showing the competitiveness of this alternative truck technology.

Comparative Assessment of Low-Level Radioactive Waste Life-Cycle Disposal Costs of U.S. Commercial Facilities

2001 ◽  
Author(s):  
E. J. Bentz ◽  
C. B. Bentz ◽  
T. D. O’Hora
Keyword(s):  
Life Cycle ◽  
Radioactive Waste ◽  
Life Cycle Cost ◽  
Regulatory Compliance ◽  
Comparative Assessment ◽  
Life Cycle Costs ◽  
Low Level ◽  
Low Level Radioactive Waste ◽  
The U.S ◽  
Total Life

Abstract This paper provides a comparative assessment of low-level radioactive waste (LLW) life-cycle costs for U.S. commercial disposal facilities. This assessment includes both currently operational facilities and planned commercial facilities. After identifying the individual facility’s operational period, current or planned capacity, and historical disposal volumes (where applicable), the paper describes the respective facilities’ waste acceptance criteria, anticipated waste characteristics, and disposal technologies employed. A brief identification of key components of cost categories that constitute life-cycle cost for the disposal facilities is provided, as well as an identification of factors that affect life-cycle cost. A more specific comparison of certain life-cycle cost components for the disposal facilities is provided, with regard to U.S. LLW disposal volumes and characteristics. Similarities and differences in total life-cycle cost and life-cycle category-specific costs among the U.S. facilities are presented and discussed. The data presented reveals that: • No new LLW commercial disposal facilities have been sited in the U.S. since 1988, and that siting of LLW disposal facilities in the U.S. has become increasingly difficult and contentious, necessitating long lead times and significant up-front costs — without any certainty of success. • Overall, life-cycle costs for LLW disposal at U.S. commercial facilities have increased significantly over time, reflecting increased regulatory compliance requirements, state-imposed access fees and taxes, local community hosting incentive costs, and cost escalation inherent in delays in establishing facilities or modifying existing licensed facilities. • Life-cycle costs are also significantly affected by the nature of the engineered isolation technology employed, reflecting the geologic characteristics of the siting location and the activity levels of the wastes accepted. • Since many of the newly-planned facilities anticipate receiving lower total volumes with an increasingly greater percentage of higher activity wastes (than historical volumes disposed) and are to be sited in more ecologically sensitive geologic regions, they will require more comprehensive — and hence more expensive — engineered isolation technologies. As a result, currently planned facilities are anticipated to experience significantly higher total life-cycle costs than existing operational facilities.

Cost–Benefit Analysis of Continuous Pavement Preservation Design Strategies versus Reconstruction

2005 ◽  
Vol 1933 (1) ◽  
pp. 83-93
Author(s):  
Kelly L. Smith ◽  
Leslie Titus-Glover ◽  
Michael I. Darter ◽  
Harold Von Quintus ◽  
Richard Stubstad ◽  
...  
Keyword(s):  
Life Cycle ◽  
Cost Benefit Analysis ◽  
Cost Benefit ◽  
Cost Effective ◽  
Life Cycle Costs ◽  
Design Strategies ◽  
Pavement Preservation ◽  
And Performance ◽  
Break Even Point ◽  
Total Life

The Arizona Department of Transportation (ADOT) has traditionally employed continuous pavement preservation as part of an overall design strategy to maintain the highest levels of service for highway users. Concerned about the effects of continual weakening of substructure material layers on preservation treatment cost and performance (i.e., more extensive and more frequent preservation activities), ADOT sponsored a study to determine the cost-effectiveness of the continuous preservation approach as compared with a reconstruction strategy. One goal of the study was to determine the break-even point for the two strategies (i.e., after how many rehabilitation treatments reconstruction becomes as cost-effective as continuous preservation). With inputs such as ( a) service life estimates, ( b) best estimates of unit costs, ( c) work zone-related user costs, and ( d) the typical analysis period and discount rate used by ADOT, the total life-cycle costs for four alternative strategies were determined and compared for the 15 commonly occurring pavement scenarios in Arizona. The results of the analysis showed a consistent reduction in total life-cycle costs as the number of rehabilitation treatments performed between original construction and reconstruction increased from none to two. Results also showed that for nine of the 15 scenarios, total life-cycle costs associated with the third reconstruction alternative (two rehabilitations occurring prior to the first reconstruction event) were within 3% of the total life-cycle costs of the continuous preservation strategy. Hence, the break-even point occurs when two to three rehabilitation treatments are performed prior to reconstruction.

scholarly journals Residential Construction with a Focus on Evaluation of the Life Cycle of Buildings

Buildings ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 524
Author(s):  
Eduard Hromada ◽  
Stanislav Vitasek ◽  
Jakub Holcman ◽  
Renata Schneiderova Heralova ◽  
Tomas Krulicky
Keyword(s):  
Life Cycle ◽  
Residential Buildings ◽  
Life Cycle Costs ◽  
The Czech Republic ◽  
Implementation Phase ◽  
Acquisition Costs ◽  
Residential Projects ◽  
Total Life

The article focuses on highlighting the role of life cycle costing (LCC) in the preparatory and implementation phase of residential projects. It involves the evaluation of several investment scenarios in the pre-investment phase, the choice between variants of the design of the entire building or its parts, and the choice of variants of structures and equipment with acceptable parameters. An innovative method of evaluating the life cycle of buildings is described in the article. This method was tested in selected residential projects realized by Skanska in the Czech Republic. Experience from construction practice shows that the choice of variants, constructions, or equipment of buildings only on the basis of the lowest acquisition costs (lowest bid prices) is wrong. The LCC calculation tool has been designed to model life cycle costs of individual variants of construction designs with different input parameters. It is possible to analyze the components or equipment that have the greatest impact on total life cycle costs. The article presents a tool that evaluates the long-term economic efficiency of the proposed residential buildings in terms of analysis of life cycle costs. The article will also expand the knowledge of the professional and general public about the importance of examining investment and operating costs already in the phase of construction preparation.

Design of Competitive Maintenance Service for Durable and Capital Goods Using Life Cycle Simulation

2009 ◽  
Vol 3 (1) ◽  
pp. 63-70 ◽  
Author(s):  
Hitoshi Komoto ◽  
◽  
Tetsuo Tomiyama ◽  
Keyword(s):  
Life Cycle ◽  
Durable Goods ◽  
User Behavior ◽  
Life Cycles ◽  
Economic Feasibility ◽  
Industrial Robots ◽  
User Preference ◽  
Capital Goods ◽  
Cycle Simulation ◽  
Maintenance Service

Maintenance is crucial in the life cycles of such durable goods as computers, cars, and office equipment and of such capital goods as machine tools and industrial robots. We developed a life cycle simulation model for analyzing maintenance in a life cycle while varying user behavior in a competitive environment to study the economic feasibility of integrating maintenance with other services from an auto manufacturer's perspective. We found that the feasibility of integration depends on user preference for specific service content and purchase timing and on the types of service content provided and discounted by competitors. We also found that a comprehensive maintenance package must be carefully designed considering the diversity of user behavior if sales are to be raised over those of on-the-spot maintenance.

Effect of Poor Workmanship and Lack of Smoothness Testing on Pavement Life-Cycle Costs

1996 ◽  
Vol 1539 (1) ◽  
pp. 102-109 ◽  
Author(s):  
Sameh M. Zaghloul
Keyword(s):  
Life Cycle ◽  
Evaluation Criteria ◽  
Life Cycles ◽  
Life Cycle Costs ◽  
Long Term Effects ◽  
International Roughness Index ◽  
Pavement Roughness ◽  
High Roughness ◽  
Roughness Control ◽  
Project Life

Pavement performance is commonly evaluated using the concept of pavement serviceability, in which pavement failure is defined by terminal serviceability instead of strict structural failure. The present serviceability index (PSI), the measure of pavement serviceability, is a function of pavement roughness, cracking, patching, and rutting. Pavement roughness is the major component of PSI and represents more than 95 percent of its value. Because roughness is such an important consideration, changes in roughness control pavement life cycles, and, therefore, construction quality, which influences roughness, influences performance and life cycle as well. A case study of a $120,000,000 project is presented. In this project, poor workmanship and lack of smoothness testing led to a considerably high initial roughness. A study was conducted to quantify the long-term effects of the high initial roughness. Results of this study indicate that the pavement service life of the project will be reduced significantly. In addition, a huge increase in the project life-cycle costs is expected. In another study, consideration was given to some of the available smoothness evaluation criteria in which roughness indices, such as the international roughness index and PSI, are used. Results of the study showed that most of these criteria are not capable of adequately addressing the high roughness associated with repeated transverse pumps. Recommendations for overcoming this inadequacy are presented.

Use of Heavy Duty, Lipped Channel Connections to Improve Rolling Stock Life Cycle Costs: An Analysis of Commonly Used Connection Methods

2015 ◽  
Author(s):  
Mark Lesher ◽  
Guy Prendergast ◽  
Rafael Moras
Keyword(s):  
Life Cycle ◽  
Life Cycle Cost ◽  
Rolling Stock ◽  
Life Cycle Costs ◽  
Heavy Duty ◽  
Heavy Loads ◽  
The Cost ◽  
Hot Rolled ◽  
Lower Production ◽  
Total Life

We present the results of a study in which we examined how different types of heavy-duty mechanical connections can affect total life cycle costs of rolling stock or similar equipment. The three commonly used methods for mechanical connection in the rolling stock industry include: welding, standard – through-hole bolting, and lipped channel, a newer technology. Newer designs of lipped channel connections have high/dynamic load capacities that are not considered possible with common, cold rolled channel products. Hot rolled channel products are capable of withstanding heavy loads typically experienced in welded or bolted joints. Throughout the life of rolling stock equipment, components may need to be replaced or upgraded from a new source, which may require a new mounting pattern or position. We have evaluated the total life cycle costs for the three techniques, when one includes costs for changing the mounting location or size of the bolt pattern. After evaluation of the cost results, we present several examples to show how rolling stock manufactures have used lipped channels to help them lower life cycle cost of their equipment. In addition to yielding flexibility in mounting position, the lipped channel connections facilitate the modularization and customization of products at the lower production levels associated with this industry.

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