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The purpose of this paper is to analyze the stress‐relaxation behavior of different woven fabrics under constant torsional strain in a wrinkled state. For this purpose, a new method for determination of stress‐relaxation behavior of the fabric was used while keeping the torsional strain constant.

In this study, the behavior of stress relaxation of fabric is examined with modification of wrinkle force tester sophisticated electro‐mechanical method and fabricating a device which uses a computer and micro controller, with constant torsional strain by a rotational level of 9.1 turn/m in 280°, and in 300 s.

The results depict that stress‐relaxation percentage in fabric in weft alignment is more than warp alignment and the fabrics which tolerate more torsional force, possess less stress‐relaxation percentages. In this way, with increasing polyester percentage in fabric the scale of stress‐relaxation percentage decreases. Also, adoption of data derived from experiments with Maxwell model shows that the interlaced model is a suitable model for explaining the stress relaxation decline in fabric. Correlation coefficient of fabrics in weft alignment with Maxwell model is more than warp alignment.

This study has practical implications in the clothing as well as in technical textiles areas.

Knowing visco‐elastic properties is very important. However, there is no information available to study the stress relaxation of woven fabrics under the combined influences of compression and constant torsional strains.

This paper aims to investigate the suitability of additive manufacturing to produce O-ring seals.

The O-rings were made by the PolyJet-Matrix technology using four different digital materials and then tested for relaxation properties under static and dynamic (sliding) conditions. The approximation of the relaxation curves involved modelling with a Prony series.

The PolyJet-Matrix technology offers new opportunities to model elastomeric elements, with examples being the O-rings produced and tested for their relaxation properties. Describing the behaviour of the particular materials fabricated with this technology by using relaxation functions will extend the knowledge base on digital materials.

The four types of photopolymers used in the experiment differed in viscoelastic properties. The analysis of the stress relaxation of the O-ring models was performed at four different step displacements of the loading element.

The test results may be useful for the design of O-ring seals made of new elastomeric materials. The relaxation properties of the O-rings made of such materials can be applied to analyse the dynamics of seals, for instance, face seals.

The originality of the work lies in the use of digital materials to design and produce elastomeric elements with different relaxation properties, which was confirmed by the test results. This paper presents results of a relaxation analysis for a ring model and the material that the ring is made of. It also discusses how 3D printing and digital materials can be applied in practice.

Clinical staff working in mental health services experience high levels of work-related stress, burnout and poor well-being. Increased levels of stress, burnout, depression and anxiety and poorer mental well-being among health-care workers are associated with more sick days, absenteeism, lower work satisfaction, increased staff turnover and reduced quality of patient care. Virtual reality (VR) relaxation is a technique whereby experiences of pleasant and calming environments are accessed through a head-mounted display to promote relaxation. The purpose of this paper is to describe the design of a study that assesses the feasibility and acceptability of implementing a multi-session VR relaxation intervention amongst mental health professionals, to improve their relaxation levels and mental well-being.

The study follows a pre–post-test design. Mental health staff will be recruited for five weeks of VR relaxation. The authors will measure the feasibility and acceptability of the VR relaxation intervention as primary outcomes, alongside secondary outcomes evaluating the benefits of VR relaxation for mental well-being.

The study aims to recruit 20–25 health-care professionals working in both inpatient and specialist community mental health settings.

Research indicates the potential of VR relaxation as a low-intensity intervention to promote relaxation and reduce stress in the workplace. If VR relaxation is shown to be feasible and acceptable, when delivered across multiple sessions, there would be scope for large-scale work to investigate its effectiveness as an approach to enable health-care professionals to de-stress, relax and optimise their mental well-being. In turn, this may consequently reduce turnover and improve stress-related sick leave across health-care services.

The purpose of this paper is to investigate the two-phase flow problems involving gas–liquid mixture.

The governed equations consist of a range of conservation laws modeling a classification of two-phase flow phenomena subjected to a velocity nonequilibrium for the gas–liquid mixture. Effects of the relative velocity are accounted for in the present model by a kinetic constitutive relation coupled to a collection of specific equations governing mass and volume fractions for the gas phase. Unlike many two-phase models, the considered system is fully hyperbolic and fully conservative. The suggested relaxation approach switches a nonlinear hyperbolic system into a semilinear model that includes a source relaxation term and characteristic linear properties. Notably, this model can be solved numerically without the use of Riemann solvers or linear iterations. For accurate time integration, a high-resolution spatial reconstruction and a Runge–Kutta scheme with decreasing total variation are used to discretize the relaxation system.

The method is used in addressing various nonequilibrium two-phase flow problems, accompanied by a comparative study of different reconstructions. The numerical results demonstrate the suggested relaxation method’s high-resolution capabilities, affirming its proficiency in delivering accurate simulations for flow regimes characterized by strong shocks.

While relaxation methods exhibit notable performance and competitive features, as far as we are aware, there has been no endeavor to address nonequilibrium two-phase flow problems using these methods.

This study aims to investigate the impact of overnight off-work relaxation on the performance of frontline service employees (FLEs). Specifically, the authors focused on FLEs' customer-directed extra-role service behavior (C-ERSB) and coworker-directed extra-role service behavior (CW-ERSB) as indicators of outstanding service performance. Drawing on the conservation of resources (Hobfoll, 1989) and ego depletion theories (Baumeister, 2002), the authors hypothesized that the positive effect of overnight relaxation on ERSBs will be mediated by the state of recovery. Additionally, the authors examined the boundary conditions of these relationships by testing the moderating effects of work–family conflict (WFC) and family–work conflict (FWC).

The study employed an episodic sampling method. One hundred thirty-five FLEs completed two daily surveys (before- and after-work) over five consecutive workdays, yielding 636 time-lagged day-level observations. Multilevel path modeling was performed to analyze the mediation and second-stage moderated mediation effects.

Results showed that overnight off-work relaxation was positively related to FLEs' next-day C-ERSB and CW-ERSB via next-morning recovery state. The positive relationship between overnight off-work relaxation and the next-morning recovery state was weaker for FLEs who experienced overnight WFC. FWC during work hours weakened the positive relationship between the next-morning recovery state and CW-ERSB, but not the relationship between the next-morning recovery state and C-ERSB.

The study used an episodic sampling method to reveal the significance of off-work relaxation, recovery and family–work interface on FLEs' ERSBs, a critical yet underexplored phenomenon in service literature. This study sheds light on the pathways to achieve exceptional service performance by revealing the importance of overnight off-work relaxation and the conditions that promote ERSBs.

The purpose of this paper is to propose a warranty-based bilateral automated multi-issue negotiation approach.

A methodology for bilateral automated negotiation process is developed considering the targets such as warranty attractiveness, warranty cost, mean time between failures, spare parts cost to the end user over the useful life of the life. The negotiation methodology is explained using different cases of negotiation. The optimization for each negotiation step is carried out using genetic algorithm with elitism strategy.

The result after optimization indicates that the desired target values are achieved and manufacturer obtained desired profit margin.

Application of automated negotiation model is illustrated using a real life case of an automobile engine manufacturer. The proposed approach helps the manufacturer of any product to develop a methodology for carrying out the negotiation process. The approach also results into taking warranty-related decisions at the design stage.

This paper contributes in proposing a generalized methodology for warranty-based negotiation in which the negotiation is carried out between the manufacturer and the customer.

This paper aims to present an evolutionary algorithm (EA) to accelerate the convergence for the radiative transfer equation (RTE) numerical solution using high-order and high-resolution schemes by the relaxation coefficients optimization.

The objective function minimizes the residual value difference between iterations in each control volume until its difference is lower than the convergence criterion. The EA approach is evaluated in two configurations, a two-dimensional cavity with scattering media and absorbing media.

Experimental results show the capacity to obtain the numerical solution for both cases on all interpolation schemes tested by the EA approach. The EA approach reduces CPU time for the RTE numerical solution using SUPERBEE, SWEBY and MUSCL schemes until 97% and 135% in scattering and absorbing media cases, respectively. The relaxation coefficients optimized every two numerical solution iterations achieve a significant reduction of the CPU time compared to the deferred correction procedure with fixed relaxation coefficients.

The proposed EA approach for the RTE numerical solution effectively reduces the CPU time compared to the DC procedure with fixed relaxation coefficients.

The purpose of this paper is to present numerical studies on thermally induced vibrations of piezo‐thermo‐viscoelastic composite beam subjected to a transient thermal load using coupled finite element method.

The thermal relaxation and viscoelastic relaxations are taken into consideration to obtain the system response. The concept of “memory load” along with the thermal relaxation is accounted for viscoelastic core material. The influence of type of core material on the response of the system also analyzed.

The findings show viscoelastic behavior with relaxation times in composite sandwich structures.

The paper shows accounting relaxation times as a memory load in composite sandwich structures.

In this paper, special attention is focused on the study of the relaxation phenomena of fabrics containing elastane yarn.

For this purpose, the relaxation phenomena of wound fabric under constant deformation, as the consequence of accumulated stress during winding, were analysed. Maxwell's model and the modified standard linear solid model are used for explaining the relaxation.

The results of the study of the relaxation phenomena of fabrics containing elastane yarn show a close connection between stress relaxation under constant deformation in the fabric roll and the degree of deformation with manual unwinding. Expert knowledge of the relaxation phenomena in fabrics containing elastane yarns has a big influence on explaining the problem of dimensional changes and instability in such fabrics.

A better understanding of the relaxation phenomena in fabrics containing elastane yarns.