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The paper presents a mathematical problem involving quasistatic contact between a thermo-electro-viscoelastic body and a lubricated foundation, where the contact is described using a version of Coulomb’s law of friction that includes normal damped response conditions and heat exchange with a conductive foundation. The constitutive law for the material is thermo-electro-viscoelastic. The problem is formulated as a system that includes a parabolic equation of the first kind for the temperature, an evolutionary elliptic quasivariational inequality for the displacement and a variational elliptic equality for the electric stress. The author establishes the existence of a unique weak solution to the problem by utilizing classical results for evolutionary quasivariational elliptic inequalities, parabolic differential equations and fixed point arguments.

The author establishes a variational formulation for the model and proves the existence of a unique weak solution to the problem using classical results for evolutionary quasivariational elliptic inequalities, parabolic difierential equations and fixed point arguments.

The author proves the existence of a unique weak solution to the problem using classical results for evolutionary quasivariational elliptic inequalities, parabolic difierential equations and fixed point arguments.

The author studies a mathematical problem between a thermo-electro-viscoelastic body and a lubricated foundation using a version of Coulomb’s law of friction including the normal damped response conditions and the heat exchange with a conductive foundation, which is original and requires a good understanding of modeling and mathematical tools.

Internal gearings are commonly used in transmissions due to their advantages like high-power density. To ensure high efficiency, load-carrying capacity and good noise behavior, a profound knowledge of the local gear mesh is essential. The tooth contact of internal gears relates to a convex and concave surface that form a conformal contact. This is in contrast to external gears, where two convex surfaces form a contraformal contact. This paper aims at a better understanding of conformal contacts under elastohydrodynamic lubrication (EHL) to improve the design of internal gearings.

An existing numerical EHL model is used for studying the characteristic properties of a hard conformal EHL line contact. A hard contraformal EHL line contact is studied as reference. Non-Newtonian fluid behavior and thermal effects are considered. By taking into account the local contact conformity and kinematics, the effects and relevance of the curvature of the lubricant gap and micro-slip are analyzed. In a parameter study, scale effects of the contact radii on film thickness, temperature rise and friction are examined.

The curvature of the lubricant gap and effects of micro-slip are small in hard conformal EHL line contacts. For high micro-slip, it can be neglected. Hence, the modeling of conformal contacts using an equivalent geometry of the contact problem is reasonable. The parameter study shows beneficial tribological aspects of the conformal contact compared to the contraformal contact. Higher film thickness and lower fluid coefficient of friction are observed for conformal contacts, which can be attributed to lower pressures for the case of the same external normal force, or to a higher contact temperature rise for the case of equivalent contact pressure.

Despite its widespread existence, the local geometry and kinematics in hard conformal EHL line contacts like in internal gearings have been rarely studied. The findings help for a better understanding of local contact characteristics and its relevance. The quantified scale effects help to improve the efficiency and load-carrying capacity of machine elements with hard conformal EHL contacts, like internal gearings.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2022-0366/

This paper aims to study the influence of the dimension change of bush-pin on the pressure, oil film thickness, temperature rise and traction coefficient in contact zone by using a thermal elastohydrodynamic lubrication (EHL) model for finite line contact. Concretely, the effects of the equivalent curvature radius of the bush and the pin, and the length of the bush are investigated.

In this paper, the contact between the bush and pin is simplified as finite line contact. The lubrication state is studied by numerical simulation using steady-state line contact thermal EHL. A constitutive equation Ree–Eyring fluid is used in the calculations.

It is found that by selecting an optimal equivalent radius of curvature and prolonging the bush length can improve the lubrication state effectively.

Under specific working conditions, there exists an optimal equivalent radius to maximize the minimum oil film thickness in the contact zone. The increase of generatrix length will weaken the stress concentration effect in the rounded corner area at both ends of the bush, which can improve the wear resistance of chain.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-10-2019-0448.

Simulations exist for the prediction of the behaviour of building structural systems under fire, including two-way coupled fire-structure interaction. However, these simulations do not include detailed models of the connections, whereas these connections may impact the overall behaviour of the structure. Therefore, this paper proposes a two-scale method to include screw connections.

The two-scale method consists of (a) a global-scale model that models the overall structural system and (b) a small-scale model to describe a screw connection. Components in the global-scale model are connected by a spring element instead of a modelled screw, and the stiffness of this spring element is predicted by the small-scale model, updated at each load step. For computational efficiency, the small-scale model uses a proprietary technique to model the behaviour of the threads, verified by simulations that model the complete thread geometry, and validated by existing pull-out experiments. For four screw failure modes, load-deformation behaviour and failure predictions of the two-scale method are verified by a detailed system model. Additionally, the two-scale method is validated for a combined load case by existing experiments, and demonstrated for different temperatures. Finally, the two-scale method is illustrated as part of a two-way coupled fire-structure simulation.

It was shown that proprietary ”threaded connection interaction” can predict thread relevant failure modes, i.e. thread failure, shank tension failure, and pull-out. For bearing, shear, tension, and pull-out failure, load-deformation behaviour and failure predictions of the two-scale method correspond with the detailed system model and Eurocode predictions. Related to combined load cases, for a variety of experiments a good correlation has been found between experimental and simulation results, however, pull-out simulations were shown to be inconsistent.

More research is needed before the two-scale method can be used under all conditions. This relates to the failure criteria for pull-out, combined load cases, and temperature loads.

The two-scale method bridges the existing very detailed small-scale screw models with present global-scale structural models, that in the best case only use springs. It shows to be insightful, for it contains a functional separation of scales, revealing their relationships, and it is computationally efficient as it allows for distributed computing. Furthermore, local small-scale non-convergence (e.g. a screw failing) can be handled without convergence problems in the global-scale structural model.

The purpose of this paper is to share a model of skilled outreach working to find and engage the hidden group of socially isolated and lonely older people who are reluctant or unable to access community activities, formal services or support. The model can inform the practice of community development, housing or other workers concerned with initiating behaviour change among older people to increase their social connectedness.

This practice-focused paper presents a description of key elements of the Ageing Better in Camden (ABC) outreach approach along with a snapshot of operational data and examples from interviews/case studies to indicate impact of the work.

ABC’s Outreach Team engaged with individuals facing significant barriers to social connection including physical and mental health problems, living alone, bereavement and caring responsibilities. A high proportion of Team engagements were with men (41%) who are typically hard to engage. In total, 23% of people who the Team met took some “Action” towards social connection. Qualitative examples indicated that encounters with the Team could be uplifting and act as a “nudge” towards “Action”. This paper discusses the need to strengthen evidence of the impact of the approach and challenges of doing so.

There are few descriptions in practice or research literature of outreach work with older people and the elements which make it effective. This paper addresses this gap.

This study aims to gain a comprehensive understanding of adolescent’s experiences of individual school social work counselling in Swedish elementary schools.

The study encompasses interviews with 16 adolescents about their experiences of individual counselling with school social workers (SSWs). The data was analysed using conventional content analysis.

The main result was the adolescents’ desire “to navigate to shore” to speak freely about their whole lives with a professional SSW and find a “ safe haven,” […] where a trusting professional cared for and comforted them in counselling. The counselling contact contributed to increased knowledge about oneself. The results reveal the importance of the SSWs paying attention and listening to the adolescents’ narratives. The creation of a coherent life narrative enables to finally end counselling and “Cast off.”

The results highlight the importance of Swedish SSWs focusing on individual counselling sessions with adolescents to provide a setting for growth.

COVID-19 has changed the way we teach and learn, including service-learning (S-L). This study examines the impacts of the work-from-home (WFH) mode on the work performance and learning outcomes of student interns on an eight-week S-L internship programme, and the key factors in terms of its success.

A qualitative research methodology is adopted by interviewing nine student interns and four supervisors from three community partner organisations (CPOs) to understand their experiences of how the WFH mode has impacted intern work performance and learning outcomes. Thematic analysis is used for the data analysis.

The interns uncover a number of negative WFH impacts on the S-L internship, including ineffective communication and management practice, low work efficiency and quality, a lack of task variety and learning opportunities and distractions in the home environment. Furthermore, five critical factors for WFH success are also identified, including prior preparation, effective communication systems, personal motivators at work, the nature of the job in relation to it being suited to the WFH mode, and organisational support.

The study examines impacts on student work performance and learning outcomes in an S-L summer internship programme operating under the WFH mode as a result of the COVID-19 pandemic. Key success factors and practical recommendations have been developed for enhancing the future success of S-L internships operating under the WFH mode.

Integrated care (IC) is mainly studied from the perspectives of organisations or employees. However, less research is focussed on how patients themselves experience person-centred (PC) IC in practice. This context-specific, small-scale study examines what PC-IC means to older patients who went through joint replacement surgery (JRS).

The data consists of ten in-depth interviews of older patients, focussing on their experiences of care during their patient journey related to joint knee or hip replacement surgery. The data were analysed with thematic analysis.

Three central dimensions of PC-IC for older patients were identified: information sharing, continuity of care and compassionate encountering. Human validation and compassionate encountering were experienced as important aspects of PC-IC. Compassionate encountering was concretised through professionals’ very small everyday practices, which made the patient feel comfortable and respected. Instead, probably due to the medical and quite straight-forward nature of the joint replacement care process, patients seem to be pleased to trust the expertise of professionals and did not necessarily expect an active role or participation in the decision-making.

This Finnish case study focusses on the patients’ authentic perceptions of what is central to person-centred IC in the specific context of JRS.

Studies on the coronavirus disease 2019 (COVID-19) tracing apps have mostly focused on how to optimize adoption and continuous use, but did not consider potential long-term effects of their introduction. This study aims to analyse whether the characteristics of the recent introduction of tracing apps may negatively impact individuals' attitudes and intentions to adopt future tracking technology.

In an online experiment across three countries (Australia, Germany, UK), the authors measured how perceived benefits of COVID-19 tracing apps as well as specific government and campaign-related factors affect privacy concerns, attitude towards future tracking apps and intention to adopt. The authors manipulated the type of provider (governmental vs private) and the type of beneficiaries of the future tracking technology app (the individual alone or also the public) as determinants of adoption.

The authors find that privacy concerns towards the COVID-19 tracing apps negatively impact attitude and intention to adopt future tracking apps. Future adoption is more likely if the app is provided by the government, whereas additional benefits to the public do not positively stimulate adoption. Second, the study analyzed different factors, including perceptions on governments and the app introduction, as well as perceived benefits.

Taking the introduction of COVID-19 apps in different countries as a basis, the authors link both perceived benefits and contextual factors to privacy concerns, attitudes towards and intention to adopt the related technology in the future. The authors hereby clarify the responsibility of governmental actors who conduct large-scale technology introductions for the future diffusion of related technologies.

The idea that user comments on journalistic articles would help to increase the quality of the media has long been greeted with enthusiasm. By now, however, these high hopes have mostly evaporated. Practical experience has shown that user participation does not automatically lead to better journalism but may also result in hate speech and systematic trolling – thus having a dysfunctional impact on journalistic actors. Although empirical journalism research has made it possible to describe various kinds of disruptive follow-up communication on journalistic platforms, it has not yet succeeded in explaining what exactly drives certain users to indulge in flaming and trolling. This paper intends to fill this gap.

It does so on the basis of problem-centered interviews with media users who regularly publish negative comments on news websites.

The evaluation allows for a nuanced view on current phenomena of dysfunctional follow-up communication on journalistic news sites. It shows that the typical “troll” does not exist. Instead, it seems to be more appropriate to differentiate disruptive commenters according to their varying backgrounds and motives. Quite often, the interviewed users display a distinct political (or other) devotion to a certain cause that rather makes them appear as “warriors of faith.” However, they are united in their dissatisfaction with the quality of the (mass) media, which they attack critically and often with a harsh tone.

The study reflects these differences by developing a typology of dysfunctional online commenters. By helping to understand their aims and intentions, it contributes to the development of sustainable strategies for stimulating constructive user participation in a post-truth age.