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Microtextured surfaces can reduce friction in tribological systems under certain contact conditions. Because it is very time-consuming to determine suitable texture patterns experimentally, numerical approaches to the design of microtextures are increasingly gaining acceptance. The purpose of this paper is to investigate to what extent the selected modeling approach affects optimized texturing.

Using the cam/tappet contact as an application-oriented example, a simplified 2D and a full 3D model are developed for determining the best possible texturing via a design study. The study explores elongated Gaussian-shaped texture elements for this purpose. The optima of the simplified 2D simulation model and the full 3D model are compared with each other to draw conclusions about the influence of the modeling strategy. The target value here is the solid body friction in contact.

For the elongated texture elements used, both the simplified 2D model and the full model result in very similar optimal texture patterns. In the selected application, the simplified simulation model can significantly reduce the computational effort without affecting the optimization result.

Depending on the selected use case, the simulation effort required for microtexture optimization can be significantly reduced by comparing different models first. Therefore, an exact physical replica of the real contact is not necessarily the primary goal when it comes to texture selection based on numerical simulations.

This article aims to develop a measurement scale for assessing agripreneurial competencies relevant to emerging economies in alignment with the SDG2 of the UN Sustainable Development Goals 2030.

The scale development procedure includes item development and refinement, data collection, reliability and validity tests and scale purification with exploratory factor analysis (EFA) and confirmatory factor analysis (CFA).

The validated scale carries eight dimensions of competencies: Agreeableness (AG), Technological Competency (TC), Competitive Spirit (CS), Innovativeness (IN), Self-Confidence (SC), Social Responsibility (SR), Conscientiousness (CO) and Leadership (LS). The analysis puts forth a good and fit model, and the new scale reports sufficient convergent and discriminant validity.

This study is focused on the agripreneurial competencies of individual agripreneurs; institutional agripreneurs are excluded from the study.

Identifying prominent agripreneurs using the scale developed from this study will aid in allocating various government and non-governmental organisations' assistance to agripreneurs. Since developing economies rely heavily on agriculture, any positive contribution can help alleviate poor economic growth, end hunger, and promote sustainable agriculture (SDG 2 of 2030).

Though several scales for measuring entrepreneurial competencies are available, there is no standard scale to measure agripreneurial competencies. This article presents the development and validation of a measurement scale to assess the major competencies of agripreneurs that influence agripreneurship performance.

Efficacious self-management at older ages requires the ability to make an accurate appraisal of one’s current and future health situation. Therefore, the purpose of this study is to explore how community living older adults, with different self-perceived health status, appraise their future health status and their future health-care and housing needs.

The study population, 555 community living older adults, aged 65–75, completed a questionnaire for self-screening of their general health status.

The results show that over 70% of the older adults, even many of those who perceive their own health status to be “poor” or “fair” and those who are “frail”, do not expect deterioration in their physical or mental health nor extra health-care or housing needs within the next half year. In addition, a substantial part of the respondents, particularly those who perceive their general health as less favourable, tend to have a “wait-and-see” attitude and want to live their life day-to-day.

Community living older adults may not always be able or motivated to monitor their own health condition and prepare themselves for changing needs. Supporting older adults by motivating and teaching them to monitor their condition and overcome barriers to engage in pro-active coping can help older adults to manage the negative consequences of ageing while they have still sufficient resources available.

The findings of this study can help health-care professionals to tailor the support of older adults’ self-management.

This study aims to investigate the influence of commercially available resins in water-based magenta pigment inkjet ink formulations on the properties of ink printability and the characteristics of ink application in food packaging. The impact of the resin on the jettability of the existing printability phase diagrams was also assessed.

Inks with different resin loadings were tested for selected properties, such as viscosity, particle size and surface tension. Stability was determined using a Turbiscan AGS turbidimeter and LumiFuge photocentrifuge analyzer. The ink layer fastness against abrasion and foodstuffs was evaluated using an Ugra device and according to PN-EN 646, respectively. JetXpert was used to assess Ricoh printhead jetting performance.

Printability diagrams successfully characterized the jettability of polyurethane inkjet inks on a multi-nozzle printhead and the binder improved droplet formation and printing precision.

Magenta water-based inkjet inks with commercial resins have been developed for printing on paper substrates. To the best of the authors’ knowledge, for the first time, inkjet ink stability was evaluated using the Turbiscan AGS and LumiFuge analyzers, and jettability models were verified using an industrial multi-nozzle printhead.

This study aims to examine the effects of firm performance on chief executive officer (CEO) turnover and the moderating role of CEO attributes on the firm performance–CEO turnover relationship.

Probit regressions were used to examine the relationship between various CEO attributes and CEO turnover and the moderation effect of firm performance on the CEO attributes–CEO turnover relationship. The sample comprises firms from the FTSE 350 Index covering the period 1999–2018.

The results indicate that firm performance negatively and significantly impacts CEO turnover. Further analysis reveals that selected CEO attributes, namely, CEO internal experience, CEO network size and CEO age, moderate the relationship between firm performance and CEO turnover. Specifically, CEO internal experience and performance combine to reduce the likelihood of CEO turnover. However, CEO network size and age when combined with firm performance increase the likelihood of CEO turnover.

The results imply that boards should pay more attention to CEO attributes in their decisions to hire and fire executive managers as these factors may affect a wide variety of firm outcomes.

This paper makes key contributions to the CEO turnover and corporate governance literature by providing evidence of key factors other than performance that can affect the CEO dismissal decision. Specifically, this study shows that CEO attributes such as CEO internal experience, CEO networks and CEO age far outweigh the importance of performance as a factor influencing CEO turnover decisions.

Externalities influence the career trajectories of self-initiated expatriates (SIEs) and their respective career crafting. This study aims to explore the international career crafting of SIEs (encompassing their proactive career reflection and construction), taking the combined external influences of complexity, chance and change into consideration.

The authors employ a qualitative (interpretative) approach, combining career crafting and the chaos theory of careers (CTC) to further understand, from an individual standpoint, the impact of externalities on the career crafting strategies of 24 SIEs who have relocated within the European Union.

The authors show that SIEs' proactively craft their careers to varying degrees and with varying frequency. The CTC – incorporating complexity, chance and change – allows for a more nuanced understanding of SIEs' career crafting.

This paper applies the concept of career crafting to an international context, exploring the impact of externalities on SIEs' careers. In this way, the authors combine two previously separate theories, extend the application of career crafting to an international career context and emphasise the role of temporality and the whole-life view of career in SIEs’ career crafting approach.

The evaluation of the haptics of water taps and wear-related changes during usage usually involves time- and cost-intensive testing. The purpose of this paper is to abstract the tribo-system between technical ceramic disks of water tap mixer cartridges to the model level and study the tribological behavior.

The friction and wear behavior was studied by means of an alumina ball-on-original alumina disk setup at different temperatures as well as under dry conditions and under lubrication by different greases. Thereby, the frictional behavior was measured in situ, and the wear losses were analyzed by means of laser scanning microscopy.

It was shown that friction and wear can behave in a contrasting way, whereby one grease might lead to low friction, that is, an easy-going movability of the water tap, but to increased wear losses. The latter, in turn, is an indicator for the usability and service life, which cannot be explained from friction alone. Thereby, the viscosity of the base oil, the grease consistency and additives were identified as relevant grease formulation parameters to allow for fluid film (re-)formation and removal of wear particles.

To the authors’ best knowledge, this is the first approach to systematically analyze the friction and wear behavior of technical ceramic disks of water tap mixer cartridges in dependency on the temperature as well as the used lubricating grease. This approach is relevant for developing screening test strategies as well as for the selection of lubricants for water tap applications.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2022-0334/

Tribological research is complex and multidisciplinary, with many parameters to consider. As traditional experimentation is time-consuming and expensive due to the complexity of tribological systems, researchers tend to use quantitative and qualitative analysis to monitor critical parameters and material characterization to explain observed dependencies. In this regard, numerical modeling and simulation offers a cost-effective alternative to physical experimentation but must be validated with limited testing. This paper aims to highlight advances in numerical modeling as they relate to the field of tribology.

This study performed an in-depth literature review for the field of modeling and simulation as it relates to tribology. The authors initially looked at the application of foundational studies (e.g. Stribeck) to understand the gaps in the current knowledge set. The authors then evaluated a number of modern developments related to contact mechanics, surface roughness, tribofilm formation and fluid-film layers. In particular, it looked at key fields driving tribology models including nanoparticle research and prosthetics. The study then sought out to understand the future trends in this research field.

The field of tribology, numerical modeling has shown to be a powerful tool, which is both time- and cost-effective when compared to standard bench testing. The characterization of tribological systems of interest fundamentally stems from the lubrication regimes designated in the Stribeck curve. The prediction of tribofilm formation, film thickness variation, fluid properties, asperity contact and surface deformation as well as the continuously changing interactions between such parameters is an essential challenge for proper modeling.

This paper highlights the major numerical modeling achievements in various disciplines and discusses their efficacy, assumptions and limitations in tribology research.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2023-0076/