•Paper suggests Flyvbjerg knocks down a straw man, not the Hiding Hand.•Paper uses a project management lens and a sample of 161 World Bank projects.•Paper connects the Hiding Hand and the Planning ...Fallacy with project performance.•Paper finds that the Hiding Hand empirically prevails over the Planning Fallacy.•Paper outlines three flaws in Flyvbjerg’s test of the Hiding Hand.
In a recent paper in this journal, “The Fallacy of Beneficial Ignorance: A Test of Hirschman’s Hiding Hand”, Professor Bent Flyvbjerg claims that there is no such thing as beneficial ignorance and that ignorance is detrimental to project success. Moreover, he argues that if Hirschman’s principle of the Hiding Hand were correct, then benefit overruns would exceed cost overruns. Thus, with a statistical test, he demonstrates that the Hiding Hand is in fact less common than its “evil twin”, the Planning Fallacy. In this rejoinder, the author shows that Flyvbjerg’s test is built on a straw man fallacy and that he fails to refute the Hiding Hand. Contrary to Flyvbjerg—who focuses on the narrow costs and benefits—this paper provides evidence that while the Hiding Hand is found among projects that are project management failures but project successes, the Planning Fallacy fits with projects that are both project management and project failures. On that basis, the author analyzes a sample of 161 World Bank-funded projects of different types and finds that the Hiding Hand prevails. While future research should ascertain this finding, the author then points out the methodological limitations of Flyvbjerg’s test. Indeed, it is ironic that the Hiding Hand, a principle crafted against the very idea of cost–benefit analysis, is refuted on that very basis. Even worse, Flyvbjerg, in his cost–benefit analysis, ignores the full life-cycle project costs and benefits, the unintended project effects, the difficulties, and problem-solving abilities so dear to Hirschman, and, thus, treats the management of projects as a kind of “black box”. Finally, the author submits that Hirschman was a behavioral project theorist, and argues that it is more important to shed light on the circumstances where the Hiding Hand works than to question whether the principle of the Hiding Hand is right.
•Multi-objective optimisation is an efficient method in energy and cost-optimality analyses of buildings.•It is more cost-effective to improve the energy performance of the HVAC and energy systems ...than the energy performance of the building envelope.•Heat pump systems are more cost-effective and energy efficient than district heating.•External financial support is needed to encourage apartment building owners to conduct deep renovations towards nZEBs.
The paper presents cost-optimal energy performance improving measures conducted in deep renovations of typical Finnish (cold climate) brick apartment buildings, built in the 1960’s. The study discusses the effects of different renovation measures on the energy performance and economic viability in a selected building. Energy performance is studied from the primary energy consumption’s perspective and cost-effective renovation measures to meet higher energy performance criteria are also studied. The cost-optimal renovation concepts to meet different energy performance criteria were determined from over 2 billion potential renovation measure combinations by using sophisticated simulation-based multi-objective optimisation (SBMOO) analysis, utilising the advanced Pareto-Archive NSGA-II genetic algorithm, as the main research method. The SBMOO analysis was used to minimise the primary energy consumption and the net present value of life-cycle cost over a 25-year discount period simultaneously. The results indicate that the cost optimum renovation solutions of the brick apartment building stock provide the same energy performance criteria as the current national minimum energy performance requirements of new apartment buildings. According to the study, the investments should be focused on high performance renewable energy production systems, which deliver the best return on investment. External financial support mechanisms are also required to encourage apartment building owners to conduct deep renovations towards nearly zero-energy apartment buildings.
Inspection and maintenance (I&M) is essential to ensure the integrity of feeder pipes, which are parts of the primary heat transport system in a nuclear power plant. The pipes are subject to flow ...accelerated corrosion (FAC), which can compromise the integrity of the piping system and lead to high repair costs. We explore the opportunity for improving I&M strategies while ensuring that the system still maintains an acceptable level of reliability. To this aim, a reliability-based planning framework is proposed, in which every pipe in the system meets the minimum thickness requirement at a specified annual probability. With this planning framework we can a) evaluate the performance of any I&M strategy constrained to a fixed reliability criterion, without requiring this strategy to be specifically designed for such a criterion; and b) find an I&M strategy optimized for this reliability level using a heuristic description of the strategy space. We demonstrate the framework with a case study, where the wall thinning due to FAC is modeled as a Gamma process with uncertain parameters. We compare the expected life-cycle cost of multiple strategies for I&M of a feeder system with 480 pipes. The proposed approach is compared with an I&M strategy currently used by the industry, which highlights the efficiency of the proposed optimization method.
•Reliability-based inspection and maintenance (I&M) of nuclear piping systems.•Performance assessment of any I&M strategy under a fixed reliability constraint.•Heuristic description of I&M rules for optimal strategy at given reliability level.•Framework demonstrated on a 480-pipe system subject to flow accelerated corrosion.•Lower strategy cost when including reliability computations in the decision process.
Penalty parameter γ and kernel parameter σ2 are two important parameters of LSSVM. In this paper, the GA-LSSVM prediction model is constructed, which the genetic algorithm was used to optimize the ...parameters. Comparing with LSSVM model, the GA-LSSVM model improves the disadvantage that the parameters can only obtained by experience. Also in order to check model prediction accuracy, the posterior difference method(PDM) was used. The calculation results show that the GA-LSSVM model has higher prediction accuracy than other models, and it is a feasible and reliable method for equipment life cycle cost prediction, also the model can be extended to other prediction fields.
The development of higher education has led to an increasing demand for campus buildings. To promote the sustainable development of campus buildings, this paper combines social willingness-to-pay ...(WTP) with the analytic hierarchy process (AHP) based on the characteristics of Chinese campus buildings to establish a life cycle assessment–life cycle cost (LCA–LCC) integrated model. Based on this model, this paper analyses the teaching building at a university in North China. The results show that the environmental impacts and economic costs are largest in the operation phase of the life cycle, mainly because of the use of electric energy. The environmental impacts and economic costs during the construction phase mainly come from the building material production process (BMPP); in this process, steel is the main source. Throughout the life cycle, abiotic depletion-fossil fuel potential (ADP fossil) and global warming potential (GWP) are the most prominent indexes. Further analysis shows that these two indexes should be the emphases of similar building assessments in the near future. Finally, this study offers suggestions for the proposed buildings and existing buildings based on the prominent problems found in the case study, with the aim to provide reference for the design, construction, and operation management of similar buildings.
•Distributed fibre optic sensors (DFOS) can be integrated with FRP laminates.•Installation during production allows the analysis to be done from real “zero state”.•Integrated DFOS system can ...accurately measure extremely large strains.•Appropriate arrangement of DFOS sensors allows for displacement (shape) analysis.•Smart, self-diagnostic components can improve the safety of bridge infrastructure.
An increase in application of advanced materials and high-tech monitoring systems is being observed in bridge engineering in recent years. The main goal is aimed at optimizing maintenance costs spent during entire lifecycle of a bridge. The paper describes the concept of the smart fibre reinforced polymer (FRP) sandwich deck panel, dedicated for newly-designed and renovated bridges. This panel is equipped with the distributed fibre optic sensing (DFOS) system, integrated with composite laminates. The DFOS system is provided to control strain and displacement measurement, further used in the structural health monitoring of a bridge. The DFOS system is characterized by the following features: accurate, reliable and distributed strain measurements, possibility of assessing shape and displacements, detection of local damages, reliable protection of the sensors, no need for surface installations, high durability, measurements from the real zero state of the structural element. Exemplary results of distributed fibre optic strain and displacement measurements performed under laboratory conditions on laminate specimens as well as the beam cut from the prototype panels are presented and compared to conventional measurements and FEM predictions.
•Bus fleet replacement can be optimized by minimizing life-cycle cost and GHG emission.•Optimizing fleet replacement with battery electric buses results in lowest emission.•Optimized life-cycle cost ...of battery electric buses is lower than hybrid buses.•An optimized percent of diesel buses in the fleet results in substantially lower LCC.•Constraints and parameters can be edited to represent individual agency requirement.
United States in 2017 emitted about 14.36% of the total global Greenhouse Gas (GHG), 27% of which comes from the transportation sector. In order to address some of these emission sources, alternative fuel technology vehicles are becoming more progressive and market ready. Transit agencies are making an effort to reduce their carbon footprint by adopting these technologies. The overarching objective of this paper is to aid transit agencies make more informed decisions regarding the process of replacing a diesel fleet with alternative-technology buses to minimize GHG emissions. This study investigates the complete course of fleet replacement using a deterministic mixed integer programming. Bus fleet replacement is optimized by minimizing the Life Cycle Cost (LCC) of owning and operating a fleet of buses and required infrastructures while reducing GHG emission simultaneously. Buses operated by Connecticut Department of Transportation (CTDOT) were used as a case-study. Results also show a significant reduction in both cost and emission for optimized replacement schedule vs the unoptimized one. Results also show that a fleet consisting of 79% Battery Electric Bus and 21% Diesel Hybrid Bus yields the least cost solution which conforms to the other operational and environmental constraints. This study also includes various sensitivity tests, that illustrates that although the magnitude of the results may vary depending on the input data, the direction remains the same. The problem formulated in this study can help any transit agencies determine the most optimized solution to their fleet replacement problem under customizable constraints or desired set of outcomes.
The Federal Aviation Administration (FAA) has taken measures to improve safety, reduce costs, increase resilience, and improve the sustainability of the United States (U.S.) airfield infrastructure ...by using a life-cycle cost analysis methodology to increase the efficient use of economic resources needed for expanding and preserving the airfield system. However, a life-cycle assessment (LCA) approach for evaluating the environmental impacts of decisions regarding airfield infrastructure has yet to be fully developed and applied. The objective of this study is to demonstrate the use of the airfield LCA framework that was developed for the FAA and can be used by U.S. airports. The comparison of alternative pavement designs at Nashville International Airport (BNA) is presented. The scope of the study was from cradle to laid; materials, materials transportation, and construction stages of the pavement life cycle are considered, and the maintenance, use and end of life stages are not considered. Primary data were acquired from BNA and secondary data were used in situations of unavailability of primary data. The case study showed that performing LCA provides opportunities for airports to consider energy use and environment-related impacts in the decision-making process.
•Life-cycle-cost of different corrosion management strategies is compared using reliability-based approach.•Reliability-based design optimization technique is used for optimum design of the RC bridge ...beams using different materials.•Time-dependent serviceability and ultimate performances of each beam subjected to corrosion is evaluated.•The time-to-repair and the number of repair operations are predicted for each beam.•The optimum corrosion management strategy is determined based on the LCCA results.
Very limited studies have been done in the past regarding quantitative comparison of different corrosion management strategies in terms of using different materials in design and repair of reinforced concrete (RC) structures from a life-cycle-cost (LCC) point of view. In this paper, a reliability-based LCC analysis (LCCA) approach is developed to compare the long-term cost effectiveness of using six commonly-used groups of materials in design and repair of RC structures, including: normal strength concrete (NSC) with traditional black steel (BS) rebars (named as NSC-BS), NSC with epoxy coated (EC) rebars (named as NSC-EC), NSC with stainless steel (SS) rebars (named as NSC-SS), high performance concrete (HPC) containing Silica Fume (SF) with BS rebars (named as HPC-SF-BS), HPC containing Slag (SL) with BS rebars (named as HPC-SL-BS), and HPC containing Fly Ash (FA) with BS rebars (named as HPC-FA-BS). In particular, an interior T-beam of an RC bridge is used as the case study structure. First, a reliability-based design optimization (RBDO) technique is proposed and is used to achieve an optimum initial design of the T-beam for each group of materials through minimizing the initial design costs, given a target ultimate reliability index for the design. Then, reliability analysis considering prevailing uncertainties is conducted to evaluate the time-dependent serviceability and ultimate performances of the structure affected by corrosion. Next, based on the evaluated time-dependent performances, the time-to-repair and the number of repair operations are predicted for each beam. Lastly, LCCA is conducted to determine the optimum corrosion management strategy.
The sustainability of housing units can be improved by integrating green building equipment and systems such as energy-efficient HVAC systems, building envelopes, water heaters, appliances, and ...water-efficient fixtures. The use of these green building measures often improves the environmental and social performances of housing units; however they can increase their initial cost and life cycle cost. This paper presents a multi-objective optimization model that is capable of optimizing housing design and construction decisions in order to generate optimal/near-optimal tradeoffs among the three sustainability objectives of maximizing the operational environmental performance of housing units, maximizing the social quality of life for their residents, and minimizing their life cycle cost. The model is designed as a multi-objective genetic algorithm to provide the capability of optimizing multiple housing objectives and criteria that include minimizing carbon footprint and water usage during housing operational phase, maximizing thermal comfort, enhancing indoor air and lighting quality, improving neighborhood quality, and minimizing life cycle cost. An application example is analyzed to illustrate the use of the developed model and evaluate its performance. The results of this analysis illustrate the novel capabilities of the model in generating 210 near-optimal tradeoff solutions for the analyzed housing example, where each represents an optimal/near-optimal and unique tradeoff among the aforementioned three sustainability optimization objectives of maximizing the operational environmental performance of housing units, maximizing the social quality of life for their residents, and minimizing their life cycle cost. These novel capabilities of the developed model are expected to improve the design and construction of housing units and maximize their overall sustainability.
•We developed a multi-objective optimization model that maximizes housing sustainability.•Objective functions of the model are housing environmental, social, and economic performances.•Environmental performance is analyzed based on its carbon footprint and water usage.•Social performance is analyzed based on thermal comfort, lighting, air, and neighborhood quality.•We examine the economic performance based on the life cycle cost of the housing unit.
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