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The purpose of this paper is to develop a method suitable for the design of reinforced concrete columns subjected to a standard fire.

The Zone Method – a ’simplified calculation method” included in Eurocode 2 – has been developed by Hertz as a manual calculation scheme for the check of fire resistance of concrete sections. The basic idea is to disregard the thermal strains and to calculate the resistance of a cross-section by reducing the concrete cross-section by a “damaged zone”. It is assumed that all fibers can reach their ultimate, temperature dependent strength. Therefore, it is a plastic concept; the information on the state of strain is lost. The calculation of curvatures and deflections is thus only possible by making further assumptions. Extensions of the zone method toward a general calculation method, suitable for the implementation in commercial design software and using the temperature dependent stress–strain curves of the Advanced Calculation Method, have been developed in Germany. The extension by Cyllok and Achenbach is presented in detail. The necessary assumptions of the Zone Method are reviewed, and an improved proposal for the consideration of the reinforcement in this extended Zone Method is presented.

The principles and assumptions of the Zone Method proposed by Hertz can be validated.

An extension of the Zone Method suitable for the implementation in design software is proposed.

The “chiralisation” of Euclidean polygonal tessellations is a novel, recent method which has been used to design new auxetic metamaterials with complex topologies and improved geometric versatility over traditional chiral honeycombs. This paper aims to design and manufacture chiral honeycombs representative of four distinct classes of 2D Euclidean tessellations with hexagonal rotational symmetry using fused-deposition additive manufacturing and experimentally analysed the mechanical properties and failure modes of these metamaterials.

Finite Element simulations were also used to study the high-strain compressive performance of these systems under both periodic boundary conditions and realistic, finite conditions. Experimental uniaxial compressive loading tests were applied to additively manufactured prototypes and digital image correlation was used to measure the Poisson’s ratio and analyse the deformation behaviour of these systems.

The results obtained demonstrate that these systems have the ability to exhibit a wide range of Poisson’s ratios (positive, quasi-zero and negative values) and stiffnesses as well as unusual failure modes characterised by a sequential layer-by-layer collapse of specific, non-adjacent ligaments. These findings provide useful insights on the mechanical properties and deformation behaviours of this new class of metamaterials and indicate that these chiral honeycombs could potentially possess anomalous characteristics which are not commonly found in traditional chiral metamaterials based on regular monohedral tilings.

To the best of the authors’ knowledge, the authors have analysed for the first time the high strain behaviour and failure modes of chiral metamaterials based on Euclidean multi-polygonal tessellations.

The purpose of the work is to provide a comprehensive review of the digital image correlation (DIC) technique for those who are interested in performing the DIC technique in the area of manufacturing.

No methodology was used because the paper is a review article.

no fundings.

Herein, the historical development, main strengths and measurement setup of DIC are introduced. Subsequently, the basic principles of the DIC technique are outlined in detail. The analysis of measurement accuracy associated with experimental factors and correlation algorithms is discussed and some useful recommendations for reducing measurement errors are also offered. Then, the utilization of DIC in different manufacturing fields (e.g. cutting, welding, forming and additive manufacturing) is summarized. Finally, the current challenges and prospects of DIC in intelligent manufacturing are discussed.

The study assessed the impact of technostress creators, work–family conflict and perceived organisational support (POS) on work engagement for employees operating within the virtual and hybrid work settings. The idea is to redefine the antecedents of work engagement in work settings that are characterised by excessive technology and work–family conflict.

Data gathered from 302 academics and support staff employees at a selected university in South Africa were utilised to assess the abovementioned relationships via variance-based structural equation modelling.

The combined effect of technostress, work–family conflict and POS on work engagement indicates that work–family conflict is a critical component in the relationship between technostress and work engagement. Although POS is seen as a job resource that lessens stress, the study found that the influence of work–family conflict is stronger than that of POS; hence, a negative influence is reported on work engagement. Despite the presence of support, overwhelming technostress creators and work–family conflict issues increase demands and influence work engagement negatively.

The results noted that, in hybrid and virtual work settings, managers can drive employee engagement by focussing on designing more favourable work–life balance (WLB) policies, providing adequate information communication technology (ICT) support, fostering aspects of positive technology and defining the boundaries between work life and family time.

The managers need to realise the detrimental effects of both technostress and work–family conflict on work engagement in virtual and hybrid work settings. Expanding the personal and job resources of individuals in hybrid and virtual settings is critical to enable them to meet the additional work demands and to manage the strain imposed by technostress. Instituting relevant organisation support has proved to be inadequate to address the challenges relating to technostress and work–family conflict. Therefore, introducing WLB policies that assist employees to set clear boundaries between work and family time to avoid burn out and spillover is critical. This is especially important when dealing with technostress creators in the remote work setting. Additionally, providing adequate ICT support as well as training related to use of different devices and software should be part of the organisational culture.

A manageable and reasonable workload should be maintained bearing in mind the complexity and ambiguity associated with the hybrid work setting. Managers should make allowances for employees to adjust managers' schedules to accommodate personal obligations, as well as adjust employees' workloads to accommodate family responsibilities. As for the coping strategy of technostress and work–family conflict, considering the positive effects of the supportive work environment is important.

This study provides a model on the interaction of the redefined antecedents (technostress and work–family conflict) of work engagement in high-tech environments such as virtual and hybrid work settings.

This study aims to model scale effects in nano-beams under torsion.

The elastostatic problem of a nano-beam is formulated by a novel stress-driven nonlocal approach.

Unlike the standard strain-driven nonlocal methodology, the proposed stress-driven nonlocal model is mathematically and mechanically consistent. The contributed results are useful for the design of modern devices at nanoscale.

The innovative stress-driven integral nonlocal model, recently proposed in literature for inflected nano-beams, is formulated in the present submission to study size-dependent torsional behavior of nano-beams.

The current study aims to investigate if different measures related to online psychosocial well-being and online behavior correlate with social media fatigue.

To understand the antecedents and consequences of social media fatigue, the stressor-strain-outcome (SSO) framework is applied. The study consists of two cross-sectional surveys that were organized with young-adult students. Study A was conducted with 1,398 WhatsApp users (aged 19 to 27 years), while Study B was organized with 472 WhatsApp users (aged 18 to 23 years).

Intensity of social media use was the strongest predictor of social media fatigue. Online social comparison and self-disclosure were also significant predictors of social media fatigue. The findings also suggest that social media fatigue further contributes to a decrease in academic performance.

This study builds upon the limited yet growing body of literature on a theme highly relevant for scholars, practitioners as well as social media users. The current study focuses on examining different causes of social media fatigue induced through the use of a highly popular mobile instant messaging app, WhatsApp. The SSO framework is applied to explore and establish empirical links between stressors and social media fatigue.

The purpose of this paper is to demonstrate the impact of the welding sequence on the substrate plate distortion during the wire and arc additive manufacturing (WAAM) process. This paper also aims to show the capability of finite element simulations in the prediction of those thermally induced distortions.

An experiment was conducted in which solid aluminum blocks were manufactured using two different welding sequences. The distortion of the substrates was measured at predefined positions and converted into bending and torsion values. Subsequently, a weakly coupled thermo-mechanical finite element model was created using the Abaqus simulation software. The model was calibrated and validated with data gathered from the experiments.

The results of this paper showed that the welding sequence of a part significantly affects the formation of thermally induced distortions of the final part. The calibrated simulation model was able to capture the different distortion behavior attributed to the welding sequences.

Within this work, a simulation model was developed capable of predicting the distortion of WAAM parts in advance. The findings of this paper can be used to improve the design of WAAM welding sequences while avoiding high experimental efforts.

This study aims to carry out an investigation of design approaches that should be used for the design of unconventional, innovative transmission system for construction yards to privilege a smooth behaviour efficiency, and the use of innovative production techniques. Results are quite surprising, as with a proper method it is possible to demonstrate that a cycloidal drive with Wolfrom topology should be an interesting solution for the proposed application.

With a functional approach, also considering materials and specifications related to the investigated application, it is possible to demonstrate that possible optimal solutions should be quite different respect to the ones that can be suggested with a conventional approach. In particular for proposed applications constraints related to encumbrances, the choice of new material has led to the innovative unconventional choice of a Wolfrom cycloidal speed reducer.

Provided solution is innovative respect current state of the art for machine currently used in construction yards: in terms of adopted transmission layout; in terms of chosen materials, resulting in an innovative solution.

Current research has strong implications on the adoption of polimeric materials for the construction of reliable transmission for harsh industrial environment as the proposed case study (concrete mixer for construction yard).

Proposed transmission system is absolutely original and innovative respect current state of art also considering proposed materials and consequently production methods. This is an example of transmission designed to be built with polymeric materials by optimizing chosen topology respect to chosen material.

This paper aims to explore how the Celtic Tiger economic boom and Great Recession influenced drug and alcohol use in one Irish city.

Semi-structured interviews were conducted with 48 people, living in Cork City, who had previously used drugs and/or alcohol problematically. All participants had engaged with services for their problematic use and had at least one year of abstinence at time of interview.

Some participants reported that their drug and/or alcohol consumption increased during the economic boom; others, who were already in (self-defined) active addiction, reported how full employment lessened some of the harms of their problematic use. For others, problematic use struck once the economy entered a downturn and, heavy drink and drug use became a means of soothing the strains of economic recession.

The paper provides two key contributions. Methodologically, it demonstrates how large-scale national quantitative data can mask local idiosyncratic tendencies, suggesting the need for mixed-method approaches for understanding drug market trends. The paper also provides insights into the impact of global and local economic conditions on drug and alcohol consumption in Ireland.

Ethics is fundamentally a science of social and collective responsibility. Ethics concerns human behavior as responsible or accountable. Because of the nature of social interaction, certain members of the society will bear greater authority, and hence, greater individual and social responsibility than others. In our world, personal responsibility and social responsibility are hardly separable. Personal responsibility becomes responsibility for the world because the person and the world are inseparable. In this chapter, we use the term responsibility from a legal, ethical, moral, and spiritual (LEMS) standpoint as some promise, commitment, obligation, sanctioned by self, morals, law, or society, to do good, and if harm results, to repair harm done on another. Hence, responsibility from a moral perspective is trustworthiness and dependability of the agent in some enterprise. Its inverse is exoneration – the extent to which one is excused from commitment and repairing the harm done to others by one’s actions. We apply the theories and constructs of executive responsibility to two contemporary cases: (1) India’s Super Rich in 2014 and (2) the Fall and Rise of Starbucks. After exploring the basic notion of responsibility, we present a discussion on the nature and obligation of corporate responsibility into three parts: Part I: Classical Understanding and Discussion on Corporate Responsibility; Part II: Contemporary Understanding and Discussion on Corporate Responsibility, and Part III: A synthesis of classical and contemporary views of responsibility and their applications to corporate executive responsibility.