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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.

In Malaysia, there are a few numbers of frameworks and checklists in order to evaluate the sustainable performance of buildings. In addition, most of these assessment frameworks or checklists focus on environmental sustainability disregarding social and economic pillars. The research in social and economic sustainability in the construction industry is pushing forward, albeit at a slow pace. In addition, the growing number of sustainable criteria in the literature highlights the importance of a systematic framework for construction initiatives. This research aims to propose a comprehensive framework based on three pillars of sustainability, and, additionally, to categorize them in a manner that is applicable for all relevant stakeholders based on their level of involvement and needs. Finally, it identifies the relation between each criterion and stage of the construction lifecycle with the assistance of an expert panel. This research produces a framework that is useful for Malaysian construction stakeholders to reinforce their approach towards sustainability through social and economic aspects that are currently underestimated in the construction industry.

This study presents a lifecycle cost model considering multi-level burn-in for operationally unrepairable systems including assembly and warranty costs. A numerical method to obtain system reliability under component replacement during burn-in is also presented with derived error bounds.

The final system reliability after component and system burn-in is obtained and warranty costs are computed. On failure during operation, the system is replaced with another that undergoes an identical burn-in procedure. Cost behaviours for a small and large system are shown in a numerical example.

There are more cost savings when system burn-in is conducted for a large system whereas a strategy focusing on component burn-in only can also result in cost savings for small systems. In addition, a minimum system burn-in duration is required before cost savings are achieved for these operationally unrepairable systems.

The operationally unrepairable system is a niche class of systems which small satellites fall under and no such study has been conducted before. The authors present a different approach towards the testing of small satellites for a constellation mission.

Highways are one of the most critical infrastructure projects with strategic impact on the countries’ development. Asphalt has been historically the main pavement material used in all highway projects, especially in Egypt. However, with the booming in concrete technology in the past two decades, concrete has become a strong rival to asphalt, especially in highway applications. Several factors impact the decision-making criteria for any highway, which differ according to the priorities and requirements of each decision-maker and the nature of the project.

This research focuses on studying and analyzing the different factors that impact the decision for selecting the material type for highways in Egypt’s pavement construction industry. The outputs of the analysis are then incorporated into a multi-decision-making tool to assess the optimum solution as per the priorities of the decision-maker. A holistic framework is developed to compare asphalt and concrete pavements solutions considering; initial cost, maintenance cost on the life cycle, construction duration, embodied energy and fuel consumption. The data collection on local highways was performed through interviewing and surveying experts in the consulting, contracting and building materials fields (total of 15 respondents).

A multi-decision-making tool developed using the superiority and inferiority ranking method for selecting the best alternate. To illustrate the practicality of the proposed framework, a case study for assessment and validation has been done on Sokhna–Quarries highway in Egypt. The framework results reveal that despite a lower initial cost and faster construction of asphalt, concrete pavement is more cost-efficient on the lifecycle time. The multi-decision-making model indicates that concrete is a better alternate for highway applications given the cost, time and energy factors considered.

The proposed model takes into consideration the important parameters in selecting the type of pavement to be constructed considering two alternates asphalt and concrete.

It has been claimed that the private finance initiative (PFI) provides value for money in the overall life of the project through the lifecycle costing (LCC) process under the umbrella of lifecycle management (LCM). The available literature points to the fact that LCC is very important in getting value for money from PFI projects. However, there is no literature available on the effect of the use of LCM in PFI projects in the UK. Therefore, the purpose of this paper is to explore the factors that influence the success of LCM in educational PFI projects.

The paper adopts a post-positivist approach to literature review. Purposive sampling is utilised with a mixed methodological approach. 6 qualitative inductive interviews offer key themes, which are further investigated using quantitative deductive questionnaires, of which 35 were issued and 26 were returned.

The paper provides empirical insights about the key success factors of LCM in the education sector. The results highlight the necessity of quality standardized data collection in a big data form. It highlights the need for a cultural shift from short- to long-term profit maximisation and service provision by the use of LCM in the PFI education sector.

A purposive sample was used to maximise the validity of data collection. Although this method has garnered concise and clear results, it is understood that this study is limited into a niche sector and a set of subsequently niche professionals. It is recommended that a larger sample be utilised and the spectrum of PFI sectors be opened up to further explore the topic.

Further investigations across different sectors of PFI project may be viewed as a good comparison, sectors such as health, accommodation and prisons. Gathering responses across all sector types could have resulted in a greater number of responses received and offer greater validity to this study.

While key success factors are clearly identified, fragmentation is seen as a barrier to the wholesale collection of such data. The responsibility, obligation to collect data for the benefit of future projects is not a priority for SMEs with little or no incentive to consider the progression of the sector. Albeit, there is evidence of one particular successful constructor/SPV, which is consolidating their business and are experiencing greater and sustained success.

This paper identifies previously unknown key influencing factors of success for educational PFI projects in relation to LCM.

The purpose of this paper is to identify appropriate concepts of multi-active façades for the renovation of multifamily buildings in Sweden and to determine which, if any, are financially viable.

A lifecycle profit (LCP) analysis was used to examine financial viability through a ten-step process, which included identifying concepts, assessing costs and prices, calculating the LCP and performing sensitivity analysis. Two existing buildings – one low rise and the other high rise – were used as reference models.

The findings were contradictory. Implementing any of the multi-active façade concepts on the high-rise building would be financially beneficial. The opposite was, however, the case for the low-rise building. Two factors causing this contradiction have been identified: the façade material before renovation and the size of the building.

The study is limited to two case buildings situated in Sweden; however, similar buildings represent a significant amount of the existing building stock. Part of the purpose of the study is also to investigate the merits of LCP analysis to evaluate energy-efficient retrofitting. The study implicates the benefits and pitfalls of LCP analysis needed to be considered by researchers and practitioners alike.

The research findings contribute to the understanding of energy-efficient retrofitting of existing multifamily buildings based on prefabricated multi-active façade concepts.

Since technological lifecycles do not always match hardware/software (HW/SW) lifecycles, obsolescence becomes a major issue in system lifecycle management as it can cause premature and unscheduled replacement of HW/SW subsystems. The purpose of this paper is to report a dynamic model to predict the obsolescence dates for HW/SW subsystems.

The dynamic model estimates obsolescence dates for HW/SW subsystems based on graph theory concept. The model depicts the stages of subsystem obsolescence through transmittances composed of probability and time-distribution elements. The model predicts probability and mean time to obsolescence for line replaceable units (LRUs) over the lifetime of the system. An illustrative example in signaling systems used in a train control system was used to demonstrate the application of this model.

Generally, the short timespan for HW/SW subsystems, which are periodically replaced with newer technologies, results in the development of new product lines by suppliers while they try to support legacy systems for a reasonable period of time. Obsolescence of HW/SW subsystems increases operation and maintenance costs as legacy systems are typically more expensive to maintain. The costs can be reduced by an optimum time to obsolescence derived from the model.

This research adds to the body of knowledge on asset management and maintenance strategy. This paper may be of particular interest to reliability, maintainability and availability practitioners and project managers.

The originality of this paper lies in developing a graph-based model that predicts probability and mean time to obsolescence for LRUs over the lifetime of the system.

In recent years, steadily rising and ever‐changing energy prices have required the development of sustainable strategies to reduce the energy consumption of buildings. Measures to improve the energy efficiency of detached houses have already been implemented. This new procedure addresses the energy efficient modernization to entire building stocks of public authorities and therefore targets to meet a key niche issue.

As result of literature research the demand for a strategic approach for energy efficient improvement was pointed out. The model framework refers to four main requirements for a new procedure within a comprehensive view of facilities management (FM), lifecycle orientation, efficient working processes, setting of objectives and monitoring of results. In addition the literature research recorded five main methods and tools which were utilized for the model development.

The new constructed facility‐energy‐efficiency model (FEE‐model) supports the decision process. The starting point is the selection of the buildings with the highest energy saving potential. The next step is a deeper analysis of the as‐is‐state in comparison with a defined target state. After that improvement areas were identified and finally a recommendation for the implementation is given. The model was tested within practical cases of which a municipal kindergarten is documented as example in this article.

The paper provides useful information on energy efficient improvement of entire building stocks.

Traditionally, early-stage investment decisions on buildings purely based initial capital costs and simply ignored running costs and total lifecycle cost. This was basically due to the absence of estimating models that yield running costs at the early design stage. Often, when the design of a building, which is responsible for 10–15% of its total cost, is completed, 80% of the total cost is committed. This study aims to develop a building characteristic-based model, which is an early-stage determinant of running costs of buildings, to predict the running costs of commercial buildings.

A desk study was carried out to collect running costs data and building characteristics of 35 commercial buildings in Sri Lanka. A Pareto analysis, bivariate correlation analysis and hedonic regression modelling were performed on collected data.

According to Pareto analysis, utilities, services, admin work and cleaning are four main cost constituents, responsible for 80% of running costs, which can be represented by highly correlated building characteristics of building height, number of floors and size. Approximately 94% of the variance in annual running costs/sq. m is expressed by variables of number of floors, net floor area and working hours/day together with a mean prediction accuracy of 2.89%.

The study has utilised a sample of 35 commercial buildings due to non-availability and difficulty in accessing running cost data.

Early-stage supportive running costs estimation model proposed by the study would enable construction professionals to benchmark the running costs and thereby optimise the building design. The developed hedonic model illustrated the variance of running costs concerning the changes in characteristics of a building.

Railway transport maintenance plays an important role in delivering safe, reliable and competitive transport services. An appropriate maintenance strategy not only reduces the assets’ lifecycle cost, but also will ensure high standards of safety and comfort for rail passengers and workers. In recent years, the majority of studies have been focused on the application of risk-based tools and techniques to maintenance decision making of railway infrastructure assets (such as tracks, bridges, etc.). The purpose of this paper is to present a risk-based modeling approach for the inspection and maintenance optimization of railway rolling stock components.

All the “potential failure modes and root causes” related to rolling stock systems are identified from an extensive literature review followed by an expert’s panel assessment. The failure causes are categorized into six groups of electrical faults, structural damages, functional failures, degradation, human errors and natural (external) hazards. Stochastic models are then proposed to estimate the likelihood (probability) of occurrence of a failure in the rolling stock system. The consequences of failures are also modeled by an “inflated cost function” that involves safety-related costs, corrective maintenance and renewal (M&R) costs, the penalty charges due to train delays or service interruptions as well as the costs associated with loss of reputation (or loss of fares) in the case of trip cancellation. Lastly, a time-varying risk-cost function is formulated to determine the optimal frequency of preventive inspection and maintenance actions for rolling stock components.

For the purpose of clearly illustrating the proposed risk-based inspection and maintenance modeling methodology, a case study of the Class 380 train’s pantograph system from a Scottish train operating company is provided. The results indicate that the proposed model has a substantial potential to reduce the M&R costs while ensuring a higher level of safety and service quality compared to the currently used inspection methodologies.

The railway rolling stocks should be regularly inspected and maintained so as to ensure network availability and reliability, passenger safety and comfort, and operations efficiency. Despite the best efforts of the maintenance staff, it is reported that a considerable amount of maintenance resources (e.g. budget, time, manpower) is wasted due to insufficiency or inefficiency of current periodic M&R interventions. The model presented in this paper helps the maintenance engineers to assess the current maintenance practices and propose or initiate improvement actions when needed.

There are few studies investigating the application of risk-based tools and techniques to inspection and maintenance decision making of railway rolling stock components. This paper presents a modeling approach aimed at planning the preventive repair and maintenance interventions for rolling stock components based on risk measures. The author’s model is also capable of incorporating real measurement information gathered at each inspection epoch to update future inspection plans.