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The aviation industry has seen consistent growth over the past few decades. To maintain its sustainability and competitiveness, it is important to have a comprehensive understanding of the environmental impacts across the entire life cycle of the industry, including materials, processes and resources; manufacturing and production; lifetime services; reuse; end-of-life; and recycling. One important component of aircraft engines, integral rotors known as Blisks, are made of high-value metallic alloys that require complex and resource-intensive manufacturing processes. The purpose of this paper is to assess the ecological and economical impacts generated through Blisk production and thereby identify significant ‘hot-spots’.

This paper focuses on the methodology and approach for conducting a full-scale Blisk life cycle assessment (LCA) based on ISO 14040/44. Unlike previous papers in the European Aerospace Science Network series, which focused on the first two stages of LCA, this publication delves into the “life cycle impact assessment” and “interpretation” stages, providing an overview of the life cycle inventory modeling, impact category selection and presenting preliminary LCA results for the Blisk manufacturing process chain.

The result shows that the milled titanium Blisk has a lower CO₂ footprint than the milled nickel Blisk, which is less than half of the global warming potential (GWP) of the milled nickel Blisk. A main contributor to GWP arises from raw material production. However, no recycling scenarios were included in the analysis, which will be the topic of further investigations.

The originality of this work lies in the detailed ecological assessment of the manufacturing for complex engine components and the derivation of hot spots as well as potential improvements in terms of eco-footprint reduction throughout the products cradle-to-gate cycle. The LCA results serve as a basis for future approaches of process chain optimisation, use of “greener” materials and individual process improvements.

The purpose of this study is to examine the application of sustainable building design and operation within a university setting to determine its economic efficacy and potential for further university investment.

This study incorporated a life cycle cost analysis (LCCA), simple payback period and discounted payback period calculations to determine the return on investment, including a sensitivity analysis when comparing the energy use and financial benefits of the sustainable design of a multi-use facility at Toronto Metropolitan University with buildings of similar size and use-type.

It was found that there is a positive business argument for Canadian Universities to consider the use of sustainable design to reduce energy use and greenhouse gas (GHG) emissions. A reasonable payback period and net present value within an institutional context were determined using a life-cycle cost assessment approach.

This study was limited to the measure of only a single location. Certain assumptions regarding energy pricing and interest rates and the related sensitivities were anchored on a single year of time, and the results of this study may be subject to change should those prices or rates become significantly different over time. Considerations for future research include a longitudinal approach combined with a more detailed analysis of the effect of use-type on the variables discussed.

For university administrators, the results of this study may encourage institutions such as universities to approach new building projects through the lens of energy efficiency and environmental sustainability.

GHG emissions are a well-proven contributor to global climate change, and buildings remain a significant source of GHG emissions in Canada due to their winter heating and summer cooling loads. As a result, sustainable building design on university campuses can mitigate this impact by optimizing and reducing energy consumption.

Research related to the economic evaluation of sustainable building design on university campuses is generally limited, and this study represents the first of its kind in regard to an LCCA of a sustainably designed building on a Canadian University campus.

The study aims to design the limited number of random working cycle as a warranty term and propose two types of warranties, which can help manufacturers to ensure the product reliability during the warranty period. By extending the proposed warranty to the consumer's post-warranty maintenance model, besides the authors investigate two kinds of random maintenance policies to sustain the post-warranty reliability, i.e. random replacement first and random replacement last. By integrating depreciation expense depending on working time, the cost rate is constructed for each random maintenance policy and some special cases are provided by discussing parameters in cost rates. Finally, sensitivities on both the proposed warranty and random maintenance policies are analyzed in numerical experiments.

The working cycle of products can be monitored by advanced sensors and measuring technologies. By monitoring the working cycle, manufacturers can design warranty policies to ensure product reliability performance and consumers can model the post-warranty maintenance to sustain the post-warranty reliability. In this article, the authors design a limited number of random working cycles as a warranty term and propose two types of warranties, which can help manufacturers to ensure the product reliability performance during the warranty period. By extending a proposed warranty to the consumer's post-warranty maintenance model, the authors investigate two kinds of random replacement policies to sustain the post-warranty reliability, i.e. random replacement first and random replacement last. By integrating a depreciation expense depending on working time, the cost rate is constructed for each random replacement and some special cases are provided by discussing parameters in the cost rate. Finally, sensitivities to both the proposed warranties and random replacements are analyzed in numerical experiments.

It is shown that the manufacturer can control the warranty cost by limiting number of random working cycle. For the consumer, when the number of random working cycle is designed as a greater warranty limit, the cost rate can be reduced while the post-warranty period can't be lengthened.

The contribution of this article can be highlighted in two key aspects: (1) the authors investigate early warranties to ensure reliability performance of the product which executes successively projects at random working cycles; (2) by integrating random working cycles into the post-warranty period, the authors is the first to investigate random maintenance policy to sustain the post-warranty reliability from the consumer's perspective, which seldom appears in the existing literature.

The aim of this study is to understand the environmental benefits and economic savings associated with adoption of circular economy in the construction sector. The research findings will support different stakeholders and decision makers to develop business models based on responsible consumption of resources and build sustainable business models.

The research uses mixed methodology wherein inventory for life cycle assessment and life cycle costing for environmental and economic impacts is based on primary data using on-site visits for qualitative and quantitative data.

Different types of land transportation infrastructures are compared for their environmental impacts. It is found that bridges have the highest environmental impacts as compared to tunnels, roads and railways. Further, the results affirm the environmental and economic benefits of adopting circular economy practices.

This is one of a kind research that compares the environmental and economic tradeoffs of adopting circular economy in different types of land transportation infrastructures.

The aim of this study is to assess the opportunity for the development of hydrocarbon transportation using high-strength steel (HSS) in pipeline construction in terms of cost savings and reliability.

Several optimizations of pipeline design and operations were performed to estimate the total life-cycle cost variation associated with different grades of high-strength steel. The generalized reduced gradient (GRG) method was used in an Excel table to determine optimal total life cycle each pipeline. Variables used in this optimization with respect to each steel grade were as follows: pipeline external diameter, wall thickness, number of compression stations and installed power in each compression station. The reliability of a pipeline with optimal cost was assessed to highlight the impact of steel grade on pipeline reliability.

The study showed that the cost reduction is strongly dependent on the adopted gas pipeline configuration. The number of compression stations and external diameter are the main factors influencing the pipeline total life cycle cost, while the steel price seems to have a minor effect, the reduction of the gas pipeline total life cycle does not exceed 5% even with a 50% difference in pipe steel prices between X70 and X100 steels. On the other side, for the same external diameter, X100 steel presents better pipeline reliability against carbonic corrosion compared to X70 steel.

The main contribution of this study is to provide a decision-support tool to help pipeline constructors enhance the profitability of natural gas transmission pipelines. The optimization method used is simple to use for design engineers during a feasibility study.

The present study presents one step to fill the gap concerning the question of balancing the trade-off between cost savings and structural reliability in high-strength steel pipelines during the early stages of feasibility studies. The optimal design and operations parameters ensuring cost savings on total life cycle costs are identified via an optimization method. The impact of selected optimal parameters on the long-term pipeline service life was estimated via a structural reliability analysis.

Cost-benefit (C/B) analysis helps to determine the economic feasibility of business software investments. Research literature and published practices do not recognize substantial software maintenance costs in C/B analysis. Current analyses emphasize the benefits of an initial investment but do not consider the recurring benefits of each enhancement during the software lifecycle. Such analyses could lead to incorrect investment decisions and lost business opportunities. This article aims to review current research on software lifecycle costs and develop a theoretically sound C/B analysis.

This article reviews current C/B analyses and discusses their shortcomings in treating the significant recurring maintenance costs. It analyzes the findings of various studies on software maintenance and synthesizes these findings to identify the nature of various maintenance costs and their benefits. Based on the synthesis, it theorizes various cost and benefit elements for inclusion in a revised C/B analysis.

This article identifies each recurring maintenance cost relevant to C/B analysis. It also identifies recurring benefits from each enhancement that hitherto have been omitted. Finally, this article discusses how these costs and benefits should be treated in the revised C/Bs analysis.

This is a conceptual paper proposing a new C/B analysis and requires an empirical validation.

This article provides a revision of the C/B analysis that is long overdue. It will help to justify a software investment correctly, rank software projects that compete for limited funds and help create a sound software project portfolio. Since 20% of software products may incur 80% of software investment, this analysis will help to make correct software investments and avoid lost business opportunities. This article also describes a practical method to use the revised C/B analysis.

This article provides a revision of the C/B analysis that is long overdue. It will help to justify a software investment correctly, rank software projects that compete for limited funds and help create a sound software project portfolio. Since 20% of software products may incur 80% of software investment, this analysis will help to make correct software investments and avoid lost business opportunities. This article also describes a practical method to use the revised C/B analysis.

The aim is to holistically assess the environmental performance of windows and analyse how their design and characteristics contribute to the overall performance of the building/space. This study focuses on the performance of windows in patient rooms hosting less mobile people.

This study investigates the life cycle environmental impacts of different glazing types, window frames and fire safety doors at the product level. This article also presents a building-integrated environmental analysis of patient rooms that considers the multiple functionalities of windows by incorporating dynamic energy analysis, comfort and daylighting performance with a life cycle assessment (LCA) study.

The results indicate that the amount of flat glass is the main contributor to the environmental impacts of the glazing units. As for the patient rooms, global warming shows the most significant contribution to the environmental costs, followed by human toxicity, particulate matter formation and eutrophication. The key drivers for these impacts are production processes and operational energy use. This study highlights the significance of evaluating a wide range of criteria for assessing the performance of windows.

An integrated assessment approach is used to investigate the influence of windows on environmental performance by considering the link between window/design parameters and their effects on energy use/costs, daylighting, comfort and environmental impacts. The embodied impacts of different building elements and the influence of various design parameters on environmental performance are assessed and compared. The environmental costs are expressed as an external environmental cost (euro).

The main purpose of this study is to provide healthcare institutions with a management accounting framework that helps them achieve their quality goals and cost targets when providing services under bundled payment schemes.

After providing a theoretical framework on both bundled payments and target costing, the success factors of the former are compared with the principles of the latter in order to analyze the compatibility and complementarity of these models. Afterwards, an example of their potential combination in practice is introduced and ideas for future research are suggested.

It is concluded that, apart from presenting similar underlying goals as regards quality and cost, bundled payments and target costing display elements in common that make them compatible from a theoretical standpoint.

Because bundled payments models are relatively new, studies on their compatibility with managerial techniques emerging from industries other than healthcare do not abound in the literature.

Firm-specific factors such as size, profitability, growth, risk and complexity, in addition to agency-related issues determine both auditor selection and firm life-cycle stage. This paper aims to examine whether and how the effect of Big-4 auditors (B4As) on client firms’ audit quality varies across firms’ life-cycle stages.

The sample comprises 1,813 firm-year observations in India’s emerging economy from 2011 to 2020. The Modified Jones model and Jones (signed, unsigned) model are used to compute discretionary accruals/audit quality. The authors use Koh et al.’s (2015) methodology to determine the firm life cycle.

The authors’ key findings show that the client firms employing B4As have superior audit quality than those employing non-Big-4 auditors (NB4As). The authors also show that the life-cycle stage significantly impacts the relationship between B4As and a firm’s audit quality. Furthermore, B4A client firms report superior audit quality vis-à-vis NB4A firms only in the birth- and decline-stages. The audit quality of growth- and mature-stage B4A and NB4A client firms is not significantly different.

Implications for managers include the decision to hire B4As. Given that B4As earn a significant fee premium, managers leading birth- and decline-stage firms should hire B4As, while managers of growth- and mature-stage firms should not.

To the best of the authors’ knowledge, this is the first paper to examine the moderating effect of the firm life-cycle stage on the selection of B4As and their impact on audit quality.

The purpose of the paper is the identification of the main factors affecting the cost of urban air mobility (UAM) based on results of ASSURED-UAM project. These factors can be found among such cost areas as investments (infrastructure, aircraft), operational, energy, end of life, delay and environmental. Once determined, they can be of great value for all UAM stakeholders, including manufacturers, urban planners and air service providers.

The obtained results were based on the outcomes of ASSURED-UAM project. Having the information about the magnitude of each cost category, we were able to identify the most costly factors of UAM. As a result, it was possible to suggest feasible cost reduction means.

For each cost category, there is the possibility to lower its value among the total cost of UAM. Each cost category has its own cost reduction means. It is vital however that the obtained results depend strongly on the assumptions made at the beginning of cost calculations.

The value of this paper is the identification of key UAM costs reduction means which may be found beneficial for all UAM stakeholders involved in the development of UAM infrastructure and services.