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Energy-efficiency measures have always been important when renovating aging building stock. For property owners, window intervention is a recurring issue. Replacement is common to reduce operational heating energy (OHE) use, something many previous building renovation studies have considered. Maintaining rather than replacing windows has received less attention, especially for multi-residential buildings in a subarctic climate where there is great potential for OHE savings. The objective was to assess the life cycle (LC) climate impact and costs of three window maintenance and replacement options for a 1980s multi-residential building in subarctic Sweden.

The options’ embodied and operational impacts from material production, transportation and space heating were assessed using a life cycle assessment (LCA) focusing on global warming potential (LCA-GWP) and life cycle costing (LCC) with a 60-year reference study period. A sensitivity analysis was used to explore the impact of uncertain parameters on LCA-GWP and LCC outcomes.

Maintaining instead of replacing windows minimized LC climate impact and costs, except under a few specific conditions. The reduced OHE use from window replacement had a larger compensating effect on embodied global warming potential (E-GWP) than investment costs, i.e. replacement was primarily motivated from a LC climate perspective. The LCA-GWP results were more sensitive to changes in some uncertain parameters, while the LCC results were more robust.

The findings highlight the benefits of maintenance over replacement to reduce costs and decarbonize window interventions, challenging property owners’ preference to replace windows and emphasizing the significance of including maintenance activities in future renovation research.

This paper aims to propose a novel model that addresses the limitations of current practices, through considering quantitative and qualitative criteria in the decision-making process for equipment replacement.

Literature review and consultation with professionals in the heavy construction industry was conducted to identify the criteria influencing the replacement of construction machines. A questionnaire survey using analytic hierarchy process and multi-attribute utility theory was used to rank these criteria and establish their utility scores. Sensitivity analysis was performed to assess how adjustments in the weights of main criteria would impact equipment replacement decisions.

The identified criteria were classified into three categories: economic, technical and socioenvironmental, encompassing a total of 15 criteria. The findings indicated that salvage value/meeting payback period/maximizing profitability held the highest importance in the replacement process, followed by considerations like high repair and maintenance cost; working condition and economic conditions. Safety and social benefits scored the least among all criteria and categories.

This study focuses on earth-moving equipment and involves experts from the Eastern Province of Saudi Arabia. The model introduces a novel methodology to aid decision-makers, particularly contractors and project managers, in determining when to replace heavy construction equipment, which results in resource efficiency and time saving.

The model integrates expertise and knowledge from experts to establish criteria for replacing construction equipment. This research aims to improve the functionality of the decision-making process regarding the acquisition or replacement of equipment throughout its lifespan.

Prediction of the duration of the downtime caused by maintenance, especially in the cases where the system considered consists of several repairable items, presents a challenge for maintenance managers, because of possible revenue losses during these intervals of time. Responds to this challenge through the new methodology for the fast, accurate prediction of maintainability measures related to the group replacement maintenance policy. It is applicable to group maintenance tasks in which individual replacement tasks are performed: simultaneously, sequentially, and combined. The method presented could be successfully used at the planning stage of the operations/production process when the information available is based on previous experience only, as well as at the stage when the process is performed. The applicability and usefulness of the methodology proposed is demonstrated through an illustrative numerical example.

A capital budgeting decision procedure appropriate for choosing the continuance, replacement, or abandonment of an asset‐in‐place is examined. The optimal replacement decision on an asset already in service requires simultaneous consideration of project life, project chaining, and possible abandonment points for both the asset‐in‐place and the replacement asset. The additional information required for the suggested procedure over the traditional replacement procedure is generally manageable and a practical solution procedure is feasible.

The subject of investigation reported in this paper is the determination of an optimal replacement time for equipment that deteriorates with time. The following hypothesis is proposed and investigated. While a piece of equipment is in the final stages of its life span, i.e. the wear‐out phase, the application of preventive replacement strategy at constant time intervals reduces total down‐time. The novelty of the approach used in this research lies in the conversion of the more complicated classical constant‐interval replacement model to a simplified but nonetheless effective model. Results are shown for a case where the equipment time‐to‐failure has a normal distribution. These results also hold for a Weibull distribution with known shape and scale parameters. The simplified methods proposed in this paper can assist maintenance managers to better make economic decisions about equipment maintenance.

The merits and demerits of replacement worker legislation continue to be a point of contention. This chapter provides empirical evidence of the impact of replacement worker bans on the outcomes of collective bargaining for the period of 1967–2009. Compared to the existing literature, this study has the advantage of using a merger of two previously separate administrative databases – the collective agreement and work stoppage databases from the Labour Program of Human Resources and Skills Development Canada (HRSDC). Under a temporary replacement worker ban, work stoppage incidence increases in the service sector, but decreases in the nonservice sector; work stoppages last longer but the wage settlements grow more slowly in both sectors. A permanent replacement worker ban increases the work stoppage incidence in the service sector and lowers the wage growth rate in the nonservice sector.

The campaign for striker replacement legislation, which began in the late 1980s and had effectively ended by the mid-1990s, was the most important political battle over labor legislation since the defeat of the Labor Law Reform Bill in 1978. Striker replacement was the AFL-CIO’s top legislative priority in the early 1990s and, coming quickly after the passage of NAFTA, which labor had opposed, the defeat of its campaign solidified organized labor’s reputation for failure in legislative battles. As yet, however, the political campaign for striker replacement legislation has attracted surprisingly little attention from industrial relations scholars.

The main purpose of present study is to model the replacement policy under uncertainty for managerial application based on grey-reliability approach by considering the subjective views of quality control circle (QCC). The study objectively links the optimality between individual replacement and group replacement policies for determining the minimum operational costs. The integrated framework between QCC, replacement theory, grey set theory and supply chain management is presented to plan replacement actions under uncertainty.

The study proposes the concept of grey-reliability index and built a decision support model, which can deal with the imprecise information for determining the minimum operational costs to plan subsequent maintenance efforts.

The findings of the study establish the synergy between individual replacement and group replacement policies. The computations related to the numbers of failures, operational costs, reliability index and failure probabilities are presented under developed framework. An integrated framework to facilitate the managers in deciding the replacement policy based on operational time towards concerning replacement of assets that do not deteriorate, but fails suddenly over time is presented. The conceptual model is explained with a numerical procedure to illustrate the significance of the proposed approach.

A conceptual model under the framework of such items, whose failures cannot be corrected by repair actions, but can only be set by replacement is presented. The study provides an important knowledge based decision support framework for crafting a replacement model using grey set theory. The study captured subjective information to build decision model in the ambit of replacement.

The costs of physical distribution, like the costs of production or marketing, consist of a number of elements whose prices are frequently determined independently and without apparent reference to each other. In the same way that production costs can be controlled by varying the inputs of capital, raw materials and labour according to their current cost relationships; or the efficiency of a marketing programme maximised through judicious adjustment of the marketing mix, so can the costs of physical distribution be minimised by scientific warehouse location, inventory control, transport mix analysis, containerisation and route planning. Widespread application of operational research techniques, industrial engineering and marketing research mean that the spectacular savings available in the past in marketing and production have been achieved.

Information on job openings by occupation is important for those looking for jobs, for those contemplating education and training options and for policy makers in education and training. Job openings in an occupation are a result of employment growth and the replacement of workers who leave the occupation. In this paper, three concepts of replacement demand are outlined and net replacement demand is estimated and projected for 81 occupational groups, covering the whole of employment in Australia. The results show the net replacement demand rate to vary substantially across occupations, with an average annual rate of 2 per cent.