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The purpose of this study was to use bridge curvature method (BCM) to quantify stress, while multiscale modeling with adaptive coarsening predicted distortions based on experimentally validated models. Taguchi method and response surface method were used to optimize process parameters (energy density, hatch spacing, scanning speed and beam diameter).

Laser powder bed fusion (LPBF) offers significant design freedom but suffers from residual stresses due to rapid melting and solidification. This study presents a novel approach combining multiscale modeling and statistical optimization to minimize residual stress in SS316L.

Optimal parameters were identified through simulations and validated with experiments, achieving an 8% deviation. This approach significantly reduced printing costs compared to traditional trial-and-error methods. The analysis revealed a non-monotonic relationship between residual stress and energy density, with an initial increase followed by a decrease with increasing hatch spacing and scanning speed (both contributing to lower energy density). Additionally, beam diameter had a minimal impact compared to other energy density parameters.

This work offers a unique framework for optimizing LPBF processes by combining multiscale modeling with statistical techniques. The identified optimal parameters and insights into the individual and combined effects of energy density parameters provide valuable guidance for mitigating residual stress in SS316L, leading to improved part quality and performance.

The ability to use laser powder bed fusion (LPBF) to print parts with tailored surface topography could reduce the need for costly post-processing. However, characterizing the as-built surface topography as a function of process parameters is crucial to establishing linkages between process parameters and surface topography and is currently not well understood. The purpose of this study is to measure the effect of different LPBF process parameters on the as-built surface topography of Inconel 718 parts.

Inconel 718 truncheon specimens with different process parameters, including single- and double contour laser pass, laser power, laser scan speed, build orientation and characterize their as-built surface topography using deterministic and areal surface topography parameters are printed. The effect of both individual process parameters, as well as their interactions, on the as-built surface topography are evaluated and linked to the underlying physics, informed by surface topography data.

Deterministic surface topography parameters are more suitable than areal surface topography parameters to characterize the distinct features of the as-built surfaces that result from LPBF. The as-built surface topography is strongly dependent on the built orientation and is dominated by the staircase effect for shallow orientations and partially fused metal powder particles for steep orientations. Laser power and laser scan speed have a combined effect on the as-built surface topography, even when maintaining constant laser energy density.

This work addresses two knowledge gaps. (i) It introduces deterministic instead of areal surface topography parameters to unambiguously characterize the as-built LPBF surfaces. (ii) It provides a methodical study of the as-built surface topography as a function of individual LPBF process parameters and their interaction effects.

The increased use cases for laser powder bed fusion (LPBF) in the research and commercial domains necessitate a better understanding of the inputs and the processing parameters. Porosity in parts manufactured by LPBF could lead to premature failure and increased cost. The powder bed, which is selectively laser melted, must be as densely packed as possible to ensure high-density parts. This paper aims to identify and qualify the variables that affect the packing density of the powder bed.

Six different independent variables that affect the packing density of the powder were identified and quantified. The chemical composition, true powder density, powder size distribution, powder circularity and convexity and powder morphology were studied. A powder bed density capsule was printed in place to determine the actual powder bed density in the LPBF unit.

Particle size destitution is the most critical aspect of the packing density in the LPBF unit. Powder with better circularity, convexity and higher powder density has proven to pack less densely than powder with many smaller particles. A more significant number of fine particles will ensure the voids between larger particles are filled, and a denser item, with less porosity, can be manufactured.

The independent variables quantified in this study to determine their effect on the packing densities are discussed. Adherence to the ASTM standard applicable to this industry is discussed, and the quantification method is evaluated. This work’s original contribution is identifying the effect of the ratio of D₉₀ to D₁₀ values based on particle diameter and its interaction within the LPBF unit to result in the highest possible packing density.

In the present study, a steel lifting lug is replaced with a composite (carbon fiber-reinforced epoxy [CFRP]) lifting lug made of a carbon/epoxy composite. The purpose of this paper was to obtain a composite lifting lug with a higher level of strength that is capable of carrying loads without failure.

The vibration and static behaviors of steel and composite lifting lugs have been investigated using finite element analysis (FEA), ANSYS software. The main consideration in the design of the composite (CFRP) lifting lug was that the displacement of both steel and composite lugs was the same under the same load. Hence, by using the FEA displacement result of the steel lifting lug, the thickness of the composite lifting lug is determined using FEA.

Compared to the steel lifting lug, the composite (CFRP) lifting lug has much lower stresses and much higher natural frequencies. Static behavior was experienced by the composite lifting lug, showing a reduction in von Mises stress, third principal stress and XZ shear stress, respectively, by 48.4%, 34.6% and 89.8%, respectively, when compared with the steel lifting lug. A higher natural frequency of mode shape swaying in X (258.976√1,000 Hz) was experienced by the composite lifting lug when compared to the steel lifting lug (195.935√1,000 Hz). The safe strength of the design composite lifting lug has been proven by FEA results, which showed that the composite (CFRP) lifting lug has a higher factor of safety in all developed stresses than the steel lifting lug. According to von Mises stress, the factor of safety of the composite lifting lug is increased by 76% when compared to the steel lifting lug. The von Mises stress at the edge of the hole in the composite lifting lug is reduced from 23.763 MPa to 20.775 MPa when compared to the steel lifting lug.

This work presents the designed composite (CFRP) lifting lug, which will be able to carry loads with more safety than a steel one.

This study aims to explore the intention to quit and its associations among ambulance personnel and to compare the intention to quit and its associations between paramedic and non-paramedic staff.

A cross-sectional study was conducted on 492 Australian ambulance personnel. Participants were selected by stratified random sampling. Data were collected using phone interview-administered questionnaires. Descriptive analyses, bivariate associations and structural equation modelling were performed for data analysis.

The study found that 70% of ambulance personnel intended to quit their jobs. Intention to quit was similar between paramedics and non-paramedic staff. In both staff groups, supervisors' and colleagues' support was associated with mental health symptoms; job satisfaction was associated with the intention to quit. Supervisors' and colleagues' support was indirectly associated with the intention to quit via increasing job satisfaction and reducing the experience of mental health symptoms among paramedics only. Mental health symptoms were directly associated with the intention to quit and indirectly associated with the intention to quit via reducing job satisfaction among paramedics only.

The study findings provide evidence for resource allocation in human resource management. The findings suggest that interventions to increase job satisfaction may reduce the intention to quit for all ambulance personnel. Interventions to improve supervisors' and colleagues' support and to manage depression, anxiety and stress symptoms may help to reduce the intention to quit for paramedics only.

This is the first study to model and compare the direct and indirect associations of intention to quit between paramedics and non-paramedic staff in ambulance personnel.

The aim of this study was to explore empirical literature on the experiences of pre-registration student nurses during mental health clinical placements and identify factors that enhance practice learning.

An integrative mixed-methods approach and constant comparative synthesis were chosen. Eligible studies were from 2009 onwards sampling student experiences of mental health placements within undergraduate and postgraduate degree entry to practice nursing programmes, excluding academic-only experiences. The search was last conducted on 14th August 2021 and included MEDLINE, CINAHL and APA PsycINFO databases.

The search strategy identified 579 studies, of which 10 met the eligibility criteria. Seven of the articles reported qualitative research; two were based on quantitative studies, and one had a mixed-methods design. There was international representation across six countries. All studies examined the experiences of pre-registration student nurses during mental health clinical placements. The total number of participants was 447, comprised of students, nongovernmental organisations and community members.

The review identified four influential themes that enhance practice learning: immersion in the nursing role; relationships that empower autonomous learning; opportunity for defined and subtle skill development; and student experiences of people with mental health needs. Further research is required on culture, subtle skill development and the socialisation process of students with the mental health nurse professional identity.

This paper offers a new perspective on the potential motivation for the adoption of employee ownership based on market power. Employee ownership may be linked to market power, either through contributing to firm growth that leads to market power or through industry leaders adopting employee ownership as part of rent sharing or a broader consolidation of market position. Both employee stock ownership plan (ESOP) coverage and product market concentration (PMC) have been increasing in the past two decades, providing a good opportunity to see if and how these are related.

The authors predict ESOP adoption and termination using multilevel regressions based on 2002–2012 firm- and industry-level data from the Census Bureau, Compustat and Form 5500 pension datasets.

The authors find that the top four firms in concentrated industries are more likely to adopt Employee Stock Ownership Plans (ESOPs), while having an ESOP does not predict entering the top four, apart from firm-level predictors. Tests indicate the first result does not reflect simple rent sharing with employees but instead appears to reflect an effort by firms to consolidate market power through the attraction and retention (or “locking in”) of industry talent. Other positive predictors of ESOPs include company size, being in a high-wage industry and having a defined benefit (DB) pension.

To better distinguish among hypotheses, it would be helpful to have firm-level data on managerial attitudes, strategies, networks and monopsony measures. Therefore, future research using such data would be highly useful and encouraged.

The paper includes implications for the potential usefulness of ESOPs in attracting and retaining talent and for the design of nuanced policy to encourage more broadly based sharing of economic rewards.

While prior research focuses on firm-level predictors of employee ownership, this study uses market concentration and other industry-level variables to predict the use of ESOPs. This study makes a unique contribution, broadening the current thinking on firm motives and environmental conditions predictive of firm ESOP adoption.

This paper aims to explore challenges and opportunities associated with young carers' employment in Australia.

Using a multi-stakeholder approach, this study captures the reflections of stakeholders (n = 8) and young carers (n = 10) about opportunities for, and experiences of, paid employment for young carers.

Despite many organisations internationally increasingly pushing diversity agendas and suggesting a commitment to equal opportunity experiences, this study found that young carers' work opportunities are often disrupted by their caring role. For young carers to be successful in their careers, organisations need to provide further workplace flexibility, and other support is required to attract and retain young carers into organisations and harness their transferrable skills for meaningful careers.

The paper highlights important implications for human resource management practitioners given the need to maximise the participation of young carers as workers, with benefits for young carers themselves, employers and society.

The research adds to the human resource management and work–family conflict literature in examining young carers through drawing on Conservation of Resources theory to highlight resources invested in caring leads to loss of educational and work experience resources. This leads to loss cycles and spirals, which can potentially continue across a lifetime, further contributing to disadvantage and lack of workplace and societal inclusion for this group of young people.

Understanding the effect of assortment composition on attentional levels is an essential topic for academic researchers and practitioners. This work has important implications when analyzing the influence of shopping frame time and search effort on the relationship between the reaction to assortment composition and visual attention to stock-keeping units (SKUs) pricing.

Two experimental studies through gauze behavior analysis technology (using eye-tracking equipment) analyze the variable's large assortment, visual attention to SKU pricing, search effort and shopping frame time.

The results suggest that, although it increases the search effort, a large assortment decreases the visual attention to SKU pricing. Further, our results indicate a moderating effect associated with mitigating the negative effect by medium-low levels of search effort and a moderating impact of time in this relation.

Marketing professionals can carefully optimize the in-store experience by managing the assortment and variety and by influencing consumers' visual attention to SKU pricing along the journey as part of the experience. Assortment and SKU pricing strategies need to be aligned with consumer journey design.

Our findings contribute to assortment theory and management by detailing the relationship between consumers' reactions to assortment perception and visual attention to SKU pricing in time flow. We reinforce the importance of considering assortment strategies from the consumer perspective and giving reliable information about in-store behavior.

The well-being of employees in distributed work has never been of more importance. This study aims to investigate the factors that empower or undermine the connectivity agency of teleworkers. Connectivity agency is an important form of autonomy for managing work–home boundaries, recuperation from work and psychological detachment. With this in mind it becomes vital to understand how connectivity agency is shaped by various contextual factors.

This qualitative study draws upon data collected from 27 teleworkers representing a variety of industries and roles. We employed a semi-structured interview protocol and analysed the data using Tracy’s (2013) iterative coding technique.

Factors that influence one’s likelihood or capacity to exercise connectivity agency exist at the individual, group or organisational level. Our data elucidate factors such as the provision of home and technological resources, the state of team norms and shared expectations and the level of organisational (dis)trust as having significant influence on whether a teleworker exercises connectivity agency, or whether attempts to do so fail altogether.

Whilst we have a comprehensive understanding of types of connectivity agency behaviours, it is unclear how one’s agency may be influenced by contextual factors. The originality and key contribution of our study is in enriching our understanding of connectivity agency to appreciate it as a dynamic phenomenon that is shaped by various contextual factors. This presents a variety of important insights for professionals leading, implementing or partaking in distributed work.