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1 – 10 of 268Mohammad A Gharaibeh, Markus Feisst and Jürgen Wilde
This paper aims to present two Anand’s model parameter sets for the multilayer silver–tin (AgSn) transient liquid phase (TLP) foils.
Abstract
Purpose
This paper aims to present two Anand’s model parameter sets for the multilayer silver–tin (AgSn) transient liquid phase (TLP) foils.
Design/methodology/approach
The AgSn TLP test samples are manufactured using pre-defined optimized TLP bonding process parameters. Consequently, tensile and creep tests are conducted at various loading temperatures to generate stress–strain and creep data to accurately determine the elastic properties and two sets of Anand model creep coefficients. The resultant tensile- and creep-based constitutive models are subsequently used in extensive finite element simulations to precisely survey the mechanical response of the AgSn TLP bonds in power electronics due to different thermal loads.
Findings
The response of both models is thoroughly addressed in terms of stress–strain relationships, inelastic strain energy densities and equivalent plastic strains. The simulation results revealed that the testing conditions and parameters can significantly influence the values of the fitted Anand coefficients and consequently affect the resultant FEA-computed mechanical response of the TLP bonds. Therefore, this paper suggests that extreme care has to be taken when planning experiments for the estimation of creep parameters of the AgSn TLP joints.
Originality/value
In literature, there is no constitutive modeling data on the AgSn TLP bonds.
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Nor Salwani Hashim and Fatimah De’nan
It is generally known that the perforated section such as the castellated section is good to sustain distributed loads but inadequate to sustain highly concentrated loads…
Abstract
Purpose
It is generally known that the perforated section such as the castellated section is good to sustain distributed loads but inadequate to sustain highly concentrated loads. Therefore, it is possible to design the opening in a different arrangement of web opening to achieve section efficiency, thus improving the strength and torsional behaviour of the section with web opening. This study aims to focus on the finite element analysis of I-beam with and without openings in steel section dominated to lateral-torsional buckling behaviour.
Design/methodology/approach
In this work, the analysis of different sizes, shapes and arrangements of web opening is performed by using LUSAS application to conduct numerical analysis on lateral-torsional buckling behaviour. This involves three diameter sizes of web opening, five types of opening shapes and two criteria of the model.
Findings
The section with c-hexagon web opening was placed about 200-mm centre to centre and 100-mm edge distance, contribute to 7.26% increase of buckling capacity. For the section with 150-mm centre to centre and 50-mm edge distance, the occurrence of local buckling contributes to decrease of lateral buckling section capacity to 19.943 kNm, where pure lateral-torsional buckling mostly occurred because of prevented section. Besides that, the web opening diameter was also analysed. The web crippling was observed because of the increase of opening diameter from 0.67 to 0.80 D.
Originality/value
This contributes to a decrease in buckling capacity as figured in the contour of the deformed shape. For Model 1, an increase of buckling capacity (31.46%) is observed when the opening diameter are changed from 0.67 to 0.80 D.
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Mustafa S. Al-Khazraji, M. J. Jweeg and S. H. Bakhy
The purpose of this paper is to investigate the free vibration response of a laminated honeycomb sandwich panels (LHSP) for aerospace applications. Higher order shear deformation…
Abstract
Purpose
The purpose of this paper is to investigate the free vibration response of a laminated honeycomb sandwich panels (LHSP) for aerospace applications. Higher order shear deformation theory (HSDT) was simplified for the dynamic analysis of LHSP. Furthermore, the effects of honeycomb parameters on the value of natural frequency (NF) of vibration were explored.
Design/methodology/approach
This paper applies HSDT to the analysis of composite LHSP to derive four vibration differential equations of motion and solve it to find the NF of vibration. Two analytical models (Nayak and Meunier models) were selected from literature for comparison of the NF of vibration. In addition, a numerical model was built by using ABAQUS and the results were compared. Furthermore, parametric studies were conducted to explore the effect of honeycomb parameters on the value of the NF of vibration.
Findings
The present model is successful in simplifying HSDT for the analysis of LHSP. The first five natural frequencies of vibration were calculated analytically and numerically. In the parametric study, increasing core height or young’s modulus or changing laminate layup will increase the value of NF of vibration. Furthermore, increasing plate constraint (using clamped edge boundary condition) will increase the value of NF of vibrations.
Research limitations/implications
The current analysis is suitable for all-composite symmetric LHSP. However, for isotropic or non-symmetric materials, minor modifications might be adopted.
Originality/value
The application of simplified HSDT to the analysis of LHSP is one of the important values of this research. The other is the successful and complete dynamic analysis of all-composite LHSP.
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Shameem Shagirbasha, Juman Iqbal, Kumar Madhan, Swati Chaudhary and Rosy Dhall
COVID-19 pandemic has overturned the work and family life challenging the world in unpredictable ways that were previously unimaginable. With universities shutting down and…
Abstract
Purpose
COVID-19 pandemic has overturned the work and family life challenging the world in unpredictable ways that were previously unimaginable. With universities shutting down and emergence of online classes, this phenomenon is prevalent among academicians as well. With this background, the current study aims to investigate the direct relationships between workplace isolation (WPI) during COVID-19 and work–family conflict (WFC) with psychological stress (PS) mediating and organizational identification (OI) moderating the relationship between the two.
Design/methodology/approach
The authors employed time lagged survey and collected data at three different time intervals (T1, T2, T3) from 203 academicians working across various universities and colleges in India. The data were analyzed quantitatively using SPSS PROCESS Macro and AMOS.
Findings
The results indicated that WPI during COVID-19 has a significant positive relationship with PS and WFC . It was also found that PS partially mediated the relationship between WPI during COVID-19 and WFC. Further, OI emerged as a potential moderator.
Originality/value
Based on the current empirical studies, it remains unclear if WPI during COVID-19 is associated with WFC. Therefore, drawing upon stress–strain–outcome (SSO) model and the conservation of resource theory, this study makes a significant contribution to the existing body of literature by exploring the unexplored associations. To the best of the authors’ knowledge, such an association has not received much scholarly attention before.
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Siqin Yao, Jintao Lu, Hanying Wang, Joel John Wark Montgomery, Tomasz Gorny and Chidiebere Ogbonnaya
Using role stress theory, this study examines how work connectivity behavior (WCB) blurs the lines between employees' work and personal lives, thereby encouraging procrastination…
Abstract
Purpose
Using role stress theory, this study examines how work connectivity behavior (WCB) blurs the lines between employees' work and personal lives, thereby encouraging procrastination at work (PAW). The study also investigates the importance of role stress and remote work self-efficacy (RWSE) as mediating and moderating factors, respectively.
Design/methodology/approach
The study examines the direct and indirect relationships between WCB and PAW using hierarchical regression and data from 415 Chinese teleworkers. RWSE is also estimated as a second-stage moderator.
Findings
The findings indicate that WCB has a direct and indirect (via role stress) positive influence on PAW; however, these effects are weaker among employees with higher (vs lower) RWSE.
Practical implications
This study assists managers and organizations in developing more efficient ways of maximizing employee and organizational performance while minimizing the counterproductive behaviors associated with excessive technology use.
Originality/value
By investigating the links between WCB and PAW in the post-pandemic context, this study adds a new perspective on how excessive technology use for work and non-work purposes can be counterproductive.
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Joeri Van den Bergh, Patrick De Pelsmacker and Ben Worsley
The purpose of this study is to identify segments in the Gen Z population (born between 1996 and 2010) in Europe, the USA and Australia, based on brand- and lifestyle-related…
Abstract
Purpose
The purpose of this study is to identify segments in the Gen Z population (born between 1996 and 2010) in Europe, the USA and Australia, based on brand- and lifestyle-related variables and perceptions about their online activities. This study explores how these segments differ and provide insights into cross-country similarities and differences.
Design/methodology/approach
An online survey was conducted with 4,304 participants, and cluster analysis and analysis of variance were used to identify and profile Gen Z segments in each of three geographical areas.
Findings
Five segments in Europe and four segments in the USA and in Australia were identified. Segments differ in terms of the importance they attach to exclusivity, inclusivity and sustainability of brands, how Gen Z members perceive money issues and stand in life and how they perceive their online activities. Similar segments are found in the three geographical areas.
Research limitations/implications
This study proposes a conceptual and analytical approach for exploring intra-cohort diversity. Future research can apply this approach to different generational cohorts and use it to study intra-cohort diversity in other parts of the world.
Practical implications
This study provides input for marketing practitioners to create better focused and more effective campaigns.
Originality/value
Cross-country generational cohort research is scarce, and especially intra-cohort diversity is under-researched. This study offers a deep and fine-grained insight into the diversity of the Gen Z cohort across three geographical areas, based on representative samples in these areas.
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Francesco Romanò, Mario Stojanović and Hendrik C. Kuhlmann
This paper aims to derive a reduced-order model for the heat transfer across the interface between a millimetric thermocapillary liquid bridge from silicone oil and the…
Abstract
Purpose
This paper aims to derive a reduced-order model for the heat transfer across the interface between a millimetric thermocapillary liquid bridge from silicone oil and the surrounding ambient gas.
Design/methodology/approach
Numerical solutions for the two-fluid model are computed covering a wide parametric space, making a total of 2,800 numerical flow simulations. Based on the computed data, a reduced single-fluid model for the liquid phase is devised, in which the heat transfer between the liquid and the gas is modeled by Newton’s heat transfer law, albeit with a space-dependent Biot function Bi(z), instead of a constant Biot number Bi.
Findings
An explicit robust fit of Bi(z) is obtained covering the whole range of parameters considered. The single-fluid model together with the Biot function derived yields very accurate results at much lesser computational cost than the corresponding two-phase fully-coupled simulation required for the two-fluid model.
Practical implications
Using this novel Biot function approach instead of a constant Biot number, the critical Reynolds number can be predicted much more accurately within single-phase linear stability solvers.
Originality/value
The Biot function for thermocapillary liquid bridges is derived from the full multiphase problem by a robust multi-stage fit procedure. The derived Biot function reproduces very well the theoretical boundary layer scalings.
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Manju Mahipalan and Naval Garg
This paper aims to examine the relationship between workplace toxicity and psychological capital (PsyCap). It also investigates the moderating role of gratitude in the…
Abstract
Purpose
This paper aims to examine the relationship between workplace toxicity and psychological capital (PsyCap). It also investigates the moderating role of gratitude in the toxicity–PsyCap link.
Design/methodology/approach
The study is based on explorative-cum-descriptive research design. The sample comprises 411 employees engaged in banking, insurance, IT, automobile and oil and gas companies. The collected data is explored for reliability, validity, multicollinearity and common method variance estimates. Also, the relationship between workplace toxicity and PsyCap and the moderating effect of gratitude are examined using structural equation modelling.
Findings
The findings report a negative association between toxicity and PsyCap. Also, the study concludes a significant moderating effect of gratitude. The study recommends the institutionalisation of a gratitude-based organisation to reduce the impact of workplace bullying and uncivil behaviour.
Originality/value
The study is based on primary data and one of the few studies that explore psychological capital as a dependent variable, which is influenced by toxic behaviours at work.
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The author develops a bilateral Nash bargaining model under value uncertainty and private/asymmetric information, combining ideas from axiomatic and strategic bargaining theory…
Abstract
The author develops a bilateral Nash bargaining model under value uncertainty and private/asymmetric information, combining ideas from axiomatic and strategic bargaining theory. The solution to the model leads organically to a two-tier stochastic frontier (2TSF) setup with intra-error dependence. The author presents two different statistical specifications to estimate the model, one that accounts for regressor endogeneity using copulas, the other able to identify separately the bargaining power from the private information effects at the individual level. An empirical application using a matched employer–employee data set (MEEDS) from Zambia and a second using another one from Ghana showcase the applied potential of the approach.
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Hubannur Seremet and Nazim Babacan
This paper aims to examine the static compression characteristics of cell topologies in body-centered cubic with vertical struts (BCCZ) and face-centered cubic with vertical…
Abstract
Purpose
This paper aims to examine the static compression characteristics of cell topologies in body-centered cubic with vertical struts (BCCZ) and face-centered cubic with vertical struts (FCCZ) along with novel BCCZZ and FCCZZ lattice structures.
Design/methodology/approach
The newly developed structures were obtained by adding extra interior vertical struts into the BCCZ and FCCZ configurations. The samples, composed of the AlSi10Mg alloy, were fabricated using the selective laser melting (SLM) additive manufacturing technique. The specific compressive strength and failure behavior of the manufactured lattice structures were investigated, and comparative analysis among them was done.
Findings
The results revealed that the specific strength of BCCZZ and FCCZZ samples with 0.5 mm strut diameter exhibited approximately a 23% and 18% increase, respectively, compared with the BCCZ and FCCZ samples with identical strut diameters. Moreover, finite element analysis was carried out to simulate the compressive response of the lattice structures, which could be used to predict their strength and collapse mode. The findings showed that while the local buckling of lattice cells is the major failure mode, the samples subsequently collapsed along a diagonal shear band.
Originality/value
An original and systematic investigation was conducted to explore the compression properties of newly fabricated lattice structures using SLM. The results revealed that the novel FCCZZ and BCCZZ structures were found to possess significant potential for load-bearing applications.
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