Life-cycle cost and performance prediction

Optimization is a field where extensive research has been conducted over the last decades. Many types of problems have been addressed, and many types of algorithms have been developed, while their range of applications is continuously growing. The chapter is divided into two parts; in the first part, the life-cycle cost analysis is used as an assessment tool for designs obtained by means of prescriptive and performance-based optimum design methodologies. The prescriptive designs are obtained through a single-objective formulation, where the initial construction cost is the objective to be minimized, while the performance-based designs are obtained through a two-objective formulation where the life-cycle cost is considered as an additional objective also to be minimized. In the second part of the chapter, the problem of inspection of structures and routing of the inspection crews following an earthquake in densely populated metropolitan areas is studied. A model is proposed and a decision support system is developed to aid local authorities in optimally assigning inspectors to critical infrastructures. A combined particle swarm – ant colony optimization based framework is implemented, which proves to be an instance of a successful application of the philosophy of bounded rationality and decentralized decision-making for solving global optimization problems.

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Construction of an evaluation system for selecting an appropriate waterproofing method for the roof of a building

Canadian Journal of Civil Engineering ◽

10.1139/l2012-070 ◽

2012 ◽

Vol 39 (12) ◽

pp. 1264-1273 ◽

Cited By ~ 5

Author(s):

Sung-Min Choi ◽

Sang-Keun Oh ◽

Chee-Ho Seo

Keyword(s):

Life Cycle ◽

Life Cycle Cost ◽

Evaluation System ◽

Evaluation Model ◽

Evaluation Criteria ◽

Value Engineering ◽

Cost Evaluation ◽

Final Decision ◽

Decision Making Processes ◽

And Performance

In this study, the discussion focus on the analysis of evaluation systems for selecting an appropriate waterproofing method, which involves a series of decision-making processes for providing unbiased, methodical, and suitable grounds to facilitate the final decision of the house owner. Thus, the research can potentially develop a decomposable model for validation and a deployable application model for the construction and performance-based design of materials. This paper has determined the performance evaluation criteria of 28 items and the evaluation index that is derived from the application of the value engineering procedure through the analysis for selecting the appropriate waterproofing method, and made a cost evaluation model of the risk based weighted life cycle cost so that life cycle cost evaluation can be performed in consideration of the risk.

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Metaheuristic Optimization in Seismic Structural Design and Inspection Scheduling of Buildings

Data Mining ◽

10.4018/978-1-4666-2455-9.ch109 ◽

2013 ◽

pp. 2132-2152

Author(s):

Chara Ch. Mitropoulou ◽

Vagelis Plevris ◽

Nikos D. Lagaros

Keyword(s):

Life Cycle ◽

Life Cycle Cost ◽

Assessment Tool ◽

Optimization Problems ◽

Construction Cost ◽

Life Cycle Cost Analysis ◽

Decentralized Decision Making ◽

And Performance ◽

Inspection Scheduling ◽

Single Objective

Optimization is a field where extensive research has been conducted over the last decades. Many types of problems have been addressed, and many types of algorithms have been developed, while their range of applications is continuously growing. The chapter is divided into two parts; in the first part, the life-cycle cost analysis is used as an assessment tool for designs obtained by means of prescriptive and performance-based optimum design methodologies. The prescriptive designs are obtained through a single-objective formulation, where the initial construction cost is the objective to be minimized, while the performance-based designs are obtained through a two-objective formulation where the life-cycle cost is considered as an additional objective also to be minimized. In the second part of the chapter, the problem of inspection of structures and routing of the inspection crews following an earthquake in densely populated metropolitan areas is studied. A model is proposed and a decision support system is developed to aid local authorities in optimally assigning inspectors to critical infrastructures. A combined particle swarm – ant colony optimization based framework is implemented, which proves to be an instance of a successful application of the philosophy of bounded rationality and decentralized decision-making for solving global optimization problems.

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Turbo-Machinery Monitoring Measures for Propulsion Safety and Affordable Readiness

Volume 3: Controls, Diagnostics and Instrumentation; Education; Electric Power; Microturbines and Small Turbomachinery; Solar Brayton and Rankine Cycle ◽

10.1115/gt2011-45741 ◽

2011 ◽

Author(s):

Richard C. Millar

Keyword(s):

Life Cycle ◽

Systems Engineering ◽

Military Service ◽

Life Cycle Cost ◽

Stress Measurement ◽

Elastic Response ◽

System Integrity ◽

Turbo Machinery ◽

And Performance ◽

Aircraft Propulsion System

The US Department of Defense initiative for propulsion safety and affordable readiness (P-SAR) has been engaged by all three services as a means to mitigate the operational and environmental hazards to aircraft propulsion system integrity, dependability and life cycle cost in military service. This paper focuses on the turbo-machinery of military propulsion systems and addresses the options available to manage turbo-machinery health and life cycle cost. Three primary turbo-machinery integrity and performance degraders are identified: foreign object damage, erosion and corrosion, and high cycle fatigue due to aero-elastic response of turbo-machine blades & vanes. A variety of sensors have been proposed as measures to monitor and mitigate the hazards created by such degradation. Many of these were developed as tools for use in component models & design verification, such as non-intrusive stress measurement systems [NSMS] — an indirect means to supplement direct on-blade strain measurements. Others tools have been defined specifically for in service monitoring, such as the use of miniature radar to detect blade motion. This paper follows a systems engineering analysis identifying alternative functional hazard mitigations and a qualitative reliability centered maintenance (RCM) view to assess alternative approaches to mitigation of each hazard. Finally, synergies across the three priority degraders are considered to recommended topics for research.

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Risk-Based Life-Cycle Cost Analysis of Privatized Infrastructure

Transportation Research Record Journal of the Transportation Research Board ◽

10.1177/0361198105192400124 ◽

2005 ◽

Vol 1924 (1) ◽

pp. 192-196 ◽

Cited By ~ 2

Author(s):

Hesham Osman

Keyword(s):

Life Cycle ◽

Cost Analysis ◽

Life Cycle Cost ◽

Life Cycle Cost Analysis ◽

Infrastructure Projects ◽

Financial Investment ◽

Relative Risks ◽

Investment Opportunities ◽

Probabilistic Values ◽

And Performance

One main shortcoming in the use of life-cycle cost analysis (LCCA) for analyzing long-term infrastructure projects is the uncertainty in the value of the LCCA parameters. Probabilistic LCCA incorporates these elements of uncertainty by assigning probabilistic values to cost and performance parameters. Studies that have performed probabilistic LCCA in the infrastructure domain propose a probability-based framework for alternative comparison. Although such frameworks convey a wealth of probabilistic information, they are not well suited to decision making. This study proposes a risk-based framework that is similar to techniques used in portfolio risk management. To illustrate the use of such a framework, a Monte Carlo simulation is used to perform probabilistic LCCA for a highway project. Two highway investment opportunities with varying risks and returns are analyzed. The decision framework is used to compare the simulation results with some common investment opportunities in the market. This framework enables private-sector investors to assess the relative risks and returns of alternative infrastructure projects. The fact that similar frameworks are used in the financial investment domain makes this approach suitable for the economic analysis of privatized infrastructure.

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A Sensitivity Study of RAP Cost and Performance on its Life Cycle Benefits

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.723.567 ◽

2013 ◽

Vol 723 ◽

pp. 567-574 ◽

Cited By ~ 2

Author(s):

Chia Pei Chou ◽

Ning Lee

Keyword(s):

Life Cycle ◽

Service Life ◽

Life Cycle Cost ◽

Sensitivity Study ◽

Cost Ratio ◽

Environmental Benefit ◽

Emission Data ◽

Carbon Reduction ◽

Financial Perspective ◽

And Performance

This study inspects the benefits of using RAP on both financial and environmental aspects from life cycle viewpoints. The Life Cycle Cost Saving (LCCS) and the Life Cycle Carbon Reduction (LCCR) of various RAP mixtures (RAP content 10%, 20%, 30%, and 40%) to the virgin mixture are introduced and applied in this study. Carbon emission data of associated materials are obtained from PaLATE database. According to calculations, the RAP mixtures corresponding cost ratio and service life ratio exceed certain thresholds to have advantages over virgin mixtures. From a financial perspective, the service life ratio of RAP mixtures to virgin mixtures must be larger than the cost ratio of these two materials. For environmental benefit, the service life of RAP mixtures must be over 70% (40% RAP) to 90% (10% RAP) of that of the virgin mixture.

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