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Recently, there has been a shift toward the embodied energy assessment of buildings. However, the impact of material service life on the life-cycle embodied energy has received little attention. We aimed to address this knowledge gap, particularly in the context of the UAE and investigated the embodied energy associated with the use of concrete and other materials commonly used in residential buildings in the hot desert climate of the UAE.

Using input–output based hybrid analysis, we quantified the life-cycle embodied energy of a villa in the UAE with over 50 years of building life using the average, minimum, and maximum material service life values. Mathematical calculations were performed using MS Excel, and a detailed bill of quantities with >170 building materials and components of the villa were used for investigation.

For the base case, the initial embodied energy was 57% (7390.5 GJ), whereas the recurrent embodied energy was 43% (5,690 GJ) of the life-cycle embodied energy based on average material service life values. The proportion of the recurrent embodied energy with minimum material service life values was increased to 68% of the life-cycle embodied energy, while it dropped to 15% with maximum material service life values.

The findings provide new data to guide building construction in the UAE and show that recurrent embodied energy contributes significantly to life-cycle energy demand. Further, the study of material service life variations provides deeper insights into future building material specifications and management considerations for building maintenance.

The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

As aging populations lead to longer working lives and increasing automation threatens job security, maintaining lifelong employability is becoming a fundamental challenge for many individuals. The purpose of this study is to examine how lifelong employability can be maintained.

Based on the theoretical perspectives of both movement capital and selection, optimization and compensation (SOC) theories, we used large-scale survey data (N = 2,256) from three European countries to investigate strategies for preserving employability among aging workers. Specifically, we explored the perceived risk of automation, lifelong learner characteristics and self-efficacy for occupational mobility as boundary conditions that may shape the negative relationship between age and employability.

We found a negative relationship between age and employability, which was more pronounced when the perceived risk of automation was higher. Furthermore, lifelong learner characteristics and self-efficacy for occupational mobility mitigated the negative relationship, so that age was not related to employability if people possessed lifelong learner characteristics and were ready for a career change.

Our study implies the importance of investing in enhancing lifelong learner characteristics and self-efficacy for occupational mobility for older employees.

Construction and Demolition (C&D) Waste Management (WM) poses significant challenges in Sri Lanka, contributing to environmental degradation and resource depletion. To address these issues, this study explores the application of Circular Economy (CE) strategies in minimising waste generation and optimising resource utilisation in Sri Lankan construction industry. The research focuses on the construction and building renovation and use and operate stages of the building project life cycle, recognising their significance in waste generation and resource consumption.

The research employed a qualitative approach, utilising the Delphi technique through three rounds of expert interviews. Seventeen experts were involved in the first round, followed by fifteen in the second round, and twelve in the final round. The collected data was analysed using manual content analysis methods.

The research findings revealed fifteen C&D WM issues in the construction and building renovation stage in Sri Lanka, along with suitable strategies to overcome each of them. Similarly, eight C&D WM issues were identified for the use and operate stage of the building, and corresponding strategies were provided to address each issue. By adopting CE strategies such as modular design and material reuse, construction projects can optimise the project's timeline, cost, and quality factors. These strategies enable efficient resource allocation, reduce waste generation, and contribute to the overall sustainability of the project. The impact of CE strategies on mitigating these issues within the project management iron triangle was also discussed.

This paper entails delving into how construction, building renovation, and operation stages of a building's life cycle intersect with CE strategies, which profoundly influence operational efficiency and long-term sustainability. By incorporating principles such as energy efficiency, water conservation, and circular product design, the paper illuminates how these strategies facilitate decreased energy usage, enhanced resource management, and diminished waste production throughout the building's lifespan.

The number of people with special needs, including citizens and military personnel, has increased as a result of terrorist attacks and challenging conditions in Iraq and other countries. With almost 80% of the world’s amputees having below-the-knee amputations, Iraq has become a global leader in the population of amputees. Important components found in lower limb prostheses include the socket, pylon (shank), prosthetic foot and connections.

There are two types of prosthetic feet: articulated and nonarticulated. The solid ankle cushion heel foot is the nonarticulated foot that is most frequently used. The goal of this study is to use a composite filament to create a revolutionary prosthetic foot that will last longer, have better dorsiflexion and be more stable and comfortable for the user. The current study, in addition to pure polylactic acid (PLA) filament, 3D prints test items using a variety of composite filaments, such as PLA/wood, PLA/carbon fiber and PLA/marble, to accomplish this goal. The experimental step entails mechanical testing of the samples, which includes tensile testing and hardness evaluation, and material characterization by scanning electron microscopy-energy dispersive spectrometer analysis. The study also presents a novel design for the nonarticulated foot that was produced with SOLIDWORKS and put through ANSYS analysis. Three types of feet are produced using PLA, PLA/marble and carbon-covered PLA/marble materials. Furthermore, the manufactured prosthetic foot undergoes testing for dorsiflexion and fatigue.

The findings reveal that the newly designed prosthetic foot using carbon fiber-covered PLA/marble material surpasses the PLA and PLA/marble foot in terms of performance, cost-effectiveness and weight.

To the best of the author’s knowledge, this is the first study to use composite filaments not previously used, such as PLA/wood, PLA/carbon fiber and PLA/marble, to design and produce a new prosthetic foot with a longer lifespan, improved dorsiflexion, greater stability and enhanced comfort for the patient. Beside the experimental work, a numerical technique specifically the finite element method, is used to assess the mechanical behavior of the newly designed foot structure.

This paper aims to establish the link between the attitudes older adults hold toward governmental websites, their subjective online public service use skills and their e-government use for bureaucratic (e.g. document downloading or filling them out online) and transactional (e.g. payment) purposes.

Data were obtained from the 2020 Israel Social Survey and analyzed using binary logistic regression models. The sample included internet users aged 60 years and older (N = 735).

Subjective use skills were positively associated with each studied type of e-government use. Perception of security in providing personal information on governmental websites was also positively associated with both types of use. Perceived clarity and simplicity of governmental websites was (positively) related to transactional e-government use only.

The results suggest that the types of e-government use in older adulthood are not contingent upon exactly the same factors. Moreover, attitudes toward e-government seem to be more relevant for transactional rather than bureaucratic e-government use in this lifespan period.

The study examines factors related to government website uses of various types in later life – a rarely studied topic in e-government research.

The study attempts to explore the effectiveness of green supply chain strategies (GSCS) and sustainable practices (SP) in achieving a circular supply chain (CSC) within a business-to-business (B2B) context. The study further investigates the moderating role of green innovation (GIN) on the relationship between GSCS and SP.

The conceptual model was developed by adopting constructs from the existing studies. A self-administered tool was created, and data were gathered from supply chain (SC) specialists in the food, energy, tire, textile and paper industries. The structural equation model was employed to test the hypothesis, analyzing 243 responses obtained.

The findings indicate an affirmative association between GSCS, SP and the achievement of CSC, with SP acting as a partial mediator between GSCS and CSC. Results show that GSCS and SP are crucial for transitioning toward a circular model in the SC, emphasizing resource regeneration and sustainability. The data from our sample suggest that GIN significantly moderates the relationship between GSCS and CSC. These insights underline the importance of green strategies and sustainable practices (SP) in fostering CSCs in a B2B setting. The study’s implications are significant for SC management, suggesting that firms must integrate green and SP to achieve circularity and long-term viability.

This article brings forward a distinctive perspective on sustainability within the field of SC management emphasizing the crucial need for implementing CSC and GSCS in a B2B context.

There is a renowned interest in adaptability as an important principle for achieving circularity in the built environment. Circular building adaptability (CBA) could enable long-term building utilisation and flexible use of space with limited material flows. This paper identifies and analyses design strategies facilitating CBA to propose a framework for enhancing the implementation of the concept.

Interviews were conducted with professionals experienced in circular building design to explore the questions “How do currently applied design strategies enable CBA?” and “How can CBA be implemented through a conceptual design framework?”. The interviews encircled multi-residential building examples to identify currently applied circular design strategies. The interviews were analysed through qualitative content analysis using CBA determinants as a coding framework.

The results show that all ten CBA determinants are supported by design strategies applied in current circular building design. However, some determinants are more supported than others, and design strategies are often employed without explicitly considering adaptability. The design strategies that enable adaptability offer long-term solutions requiring large-scale modifications rather than facilitating low-impact adaptation by dwelling occupants. The proposed conceptual design framework could aid architects in resolving these issues and implementing CBA in their circular building design.

This paper’s contribution to CBA is threefold. It demonstrates design strategies facilitating CBA, proposes a conceptual design framework to apply the concept and identifies the need for a more comprehensive application of available adaptability strategies.

This study investigates the fitting techniques for notch fatigue curves, seeking a more reliable method to predict the lifespan of welded structures.

Building on the fatigue test results of butt and cruciform joints, this research delves into the selection of fitting methods for the notch fatigue curve of welded joints. Both empirical formula and finite element methods (FEMs) were employed to assess the notch stress concentration factor at the toe and root of the two types of welded joints. Considering the mean stress correction and weld misalignment coefficients, the notch fatigue life curves were established using both direct and indirect methods.

An engineering example was employed to discern the differences between the direct and indirect approaches. The findings highlight the enhanced reliability of the indirect method for fitting the fatigue life curve.

While the notch stress approach is extensively adopted due to its accurate prediction of component fatigue life, most scholars have overlooked the importance of its curve fitting methods. Existing literature scantily addresses the establishment of these curves. This paper offers a focused examination of fatigue curve fitting techniques, delivering valuable perspectives on method selection.

The purpose of this paper is to meet Dr Joyce Shaffer, PhD, ABPP, Clinical Associate Professor at the University of Washington.

This case study is presented in two sections: a positive autoethnography written by Joyce Shaffer, followed by her answers to ten questions.

In this positive autoethnography, Shaffer shares her life story and reveals numerous mental health and positive aging recommendations and insights for us to reflect on.

This is a personal narrative, albeit from someone who has been a clinical psychologist and active in the field of aging for many decades.

A pragmatic approach to aging is recommended. According to Shaffer, “those of us who can recognize the beat of the historical drummer can harvest the best of it and learn from the rest of it.”

Positive aging has strong social implications. Shaffer considers that it is not only about maximizing our own physical, mental, emotional and social health but also about maximizing that of others, to make our world a better place for everyone.

Positive aging can be experienced despite adversity. As Shaffer says, “Adversity used for growth and healed by love is the answer.”