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The spectral boundary element method for solving two‐dimensional transient heat conduction problems is developed. This method is combined with the fast Fourier transform (FFT) to convert the solution between the time and frequency domains. The fundamental solutions in the frequency domain, required for the present method, are discussed. The resulting line integrations in the frequency domain are discretized using constant boundary elements and used in a Fortran boundary element program. Three examples are used to illustrate the accuracy and effectiveness of the method in both the frequency and time domains. First, the frequency domain solution procedure is verified using the steady‐state example of a semi‐infinite half space with a heat flux applied to a patch of the surface. This spectral boundary element method is then applied to the problem of a circular hole in an infinite solid subjected to a time‐varying heat flux, and solutions in both the frequency and time domains are presented. Finally, the method is used to solve the circular hole problem with a convection boundary condition. The accurary of these results leads to the conclusion that the spectral boundary element method in conjunction with the FFT is a viable option for transient problems. In addition, this spectral approach naturally produces frequence domain information which is itself of interest.

The purpose of this study is to investigate the thermal elastohydrodynamic lubrication (TEHL) analysis of a deep groove ball bearing.

The TEHL model for the groove ball is first established, into which the elastic deformation is incorporated. In doing so, the elastic deformation is solved with the fast Fourier transform (FFT). And the bearing temperature rise is solved by the point heat source integration method. Then, effects of the applied load, relative velocity and the slide-roll ratio on the TEHL of the bearing are analyzed.

There exist the large pressure peaks at two edges of the raceway along its width direction and the increment in the relative velocity between the roller and the raceway, or one in the slide-roll ratio arguments the temperature rise.

This study conducts a detailed discussion of the TEHL analysis of deep groove ball bearing and gives a beneficial reference to the design and application of this kind of bearings.

Pin-loaded hubs with fitted bush are used in industrial connector-type elements. They are subjected to varying radial forces leading to variable stress distribution. The literature provides various pressure distribution expressions adapted essentially for symmetric geometries and fixed load condition (circular hubs, half-infinite geometries, axial load, tangential load, etc.). This study aims to take into account the geometrical conditions of industrial connector-type elements and presents a model for pressure distribution based only on geometric parameters, maximal pressure and contact angle value for the case of fit pin-loaded hub.

The finite element computation for the contact problem shows that the pressure distribution of the pin-loaded hub under various inclined forces (from 0° to 180°) is a parabolic distribution. This distribution can be defined by three parameters which are θ_A, θ_B and P_max. The study assumes that the distribution is symmetric and that P_max can be modeled using force F, hub radius R, hub thickness b and the half contact angle are θ_A.

The new proposal pressure distribution parameters are easy to identify. Even for the non-symmetric pressure distribution, the study denotes that the errors on evaluating θ_A and θ_B keep the analytical model still in good agreement with finite element computations.

Only the neat fit case was studied.

Pin-loaded joints are connector-type elements used in mechanical assemblies to connect any structural components and linkage mechanisms such as connecting rod ends of automotive or shear joints for aircraft structure.

The good correlation between finite element computations and model results shows the validity of the assumptions adopted here. Analytical fatigue models, based on this stress distribution, could be derived in view of a fatigue lifetime calculation on connecting hub. Friction, pin deformation and local plastic effects under pin-loading are the main phenomena to take into account to further enrich this model.

The riveting process is a metal forming process involving complex elastic-plastic deformation, which will induce a compressive residual stress field and cause local distortions in the connecting areas. Regarding to the aircraft panel assemblies with plenty of rivets, the global deformation is inevitable and undesired, leading difficulties to downstream assembly processes. This paper aims to present a new method for the local distortion calculation and the global deformation prediction of sheet panel assemblies during the automated riveting process.

In this paper, a simplified algebraic study is presented to analyze the local distortion of single countersunk rivet joint with the consideration of the barrel-like shape of the driven head and the through-thickness variations along the rivet shank. Then, an equivalent rivet unit is proposed based on the result of the algebraic study and embedded into the global-level model for the prediction of the overall distortions of riveted panels.

The algebraic study is able to reach a more precise contour of the deformed rivet than the traditional assumption of cylindrical deformations and rapidly determine the equivalent coefficients of the riveting unit. The result also shows an industrial acceptable accuracy of the prediction for the global deformations of the double-layered panel assemblies widely used in the aircraft panel structures.

A new local-global method for predicting the deformations of the riveted panel assembly based on the algebraic study of the local distortions is proposed to help the engineers in the early design stages or in the assembly process planning stage.

The fuselage riveted lap-joints are susceptible to multiple site damage (MSD) and should be considered in damage tolerance analysis. This paper aims to investigate the stress intensity factor (SIF) and crack growth simulation for lap-joints based on three-dimensional (3D) finite element analysis.

The 3D finite element model of lap-joints is established by detailed representation of rivets and considering the rivet clamping force and friction. Numerical study is conducted to investigate the SIF distribution along the thickness direction and the effect of clamping force. A predictive method for the cracks propagation of MSD is then developed, in which an integral mean is adopted to quantify the SIF at crack tips, and the crack closure effect is considered. For comparison, a fatigue test of a lap-joint with MSD cracks is conducted to determine the cracks growth live and measure the cracks growth.

The numerical study shows that the through-thickness crack at riveted hole in lap-joints can be treated as mode I crack. The distribution of SIF along the thickness direction is inconstant and nonmonotonic. Besides, the increase in clamping force will lead to more frictional load transfer at the faying surfaces. The multiple crack growth simulation results agreed well with the experimental data.

The novelty of this work is that the SIF distribution along the thickness direction and the MSD cracks growth simulation for lap-joints are investigated by 3D finite element analysis, which can reflect the secondary bending, rivet clamping, contact and friction in lap-joints.

To provide a selective bibliography for researchers working with bulk material forming (specifically the forging, rolling, extrusion and drawing processes) with sources which can help them to be up‐to‐date.

A range of published (1996‐2005) works, which aims to provide theoretical as well as practical information on the material processing namely bulk material forming. Bulk deformation processes used in practice change the shape of the workpiece by plastic deformations under forces applied by tools and dies.

Provides information about each source, indicating what can be found there. Listed references contain journal papers, conference proceedings and theses/dissertations on the subject.

It is an exhaustive list of papers (1,693 references are listed) but some papers may be omitted. The emphasis is to present papers written in English language. Sheet material forming processes are not included.

A very useful source of information for theoretical and practical researchers in computational material forming as well as in academia or for those who have recently obtained a position in this field.

There are not many bibliographies published in this field of engineering. This paper offers help to experts and individuals interested in computational analyses and simulations of material forming processes.

The purpose of this study is to investigate the microstructure of fretting wear behavior in 6061-T6 aluminum alloy. The fretting wear of blind riveted lap joints of 6061-T6 aluminum alloy plates, which are widely used in aircraft construction, was investigated. Fretting damages were investigated between the contact surface of the plates and between the plate and the rivet contact surface.

Experiments were carried out using a computer controlled Instron testing machine with 200 kN static and 100 kN dynamic load capacity. Max package computer program was used for the control of the experiments. Fretting scars, width of wear scars, microstructure was investigated by metallographic techniques and scanning electron microscopy.

It was found that fretting damages were occurred between the plates contacting surface and between the plate and rivet contact surface. As load and cycles increased, fretting scars increased. Fretting wear initially begins with metal-to-metal contact. Then, the formed metallic wear particles are hardened by oxidation. These hard particles spread between surfaces, causing three-body fretting wear. Fretting wear surface width increases with increasing load and number of cycles.

The useful life of many tribological joints is limited by wear or deterioration of the fretting components due to fretting by oscillating relative displacements of the friction surfaces. Such displacements are caused by vibrations, reciprocating motion, periodic bending or twisting of the mating component, etc. Fretting also tangibly reduces the surface layer quality and produces increased surface roughness, micropits, subsurface microphone.

The purpose of this paper is to develop a numerical approach to solve the transient rolling contact problem with the consideration of velocity dependent friction.

A three dimensional (3D) transient FE model is developed in elasticity by the explicit finite element method. Contact solutions with a velocity dependent friction law are compared in detail to those with the Coulomb’s friction law (i.e. a constant coefficient of friction).

The FE solutions confirm the negligible influence of the dependence on the normal contact. Hence, analysis is focussed on the tangential solutions under different friction exploitation levels. In the trailing part of the contact patch where micro-slip occurs, very high-frequency oscillations are excited in the tangential plane by the velocity dependent friction. This is similar to the non-uniform sliding or tangential oscillations observed in sliding contact. Consequently, the micro-slip distribution varies greatly with time. However, the surface shear stress distribution is quite stable at different instants, even though it significantly changes with the employed friction model.

This paper proposes an approach to solve the transient rolling contact problem with the consideration of velocity dependent friction. Such a problem was usually solved in the literature by the simplified contact algorithms, with which detailed contact solutions could not be obtained, or with the assumption of steady rolling.

Market share gain is one of the key objectives for all firms for seeking growth. It is also a fundamental aspect of competitive rivalry. The extant review of the literature points to a gap among market share performances of emerging market multinationals (EMNEs) firms, advanced economy multinationals (AMNEs) and local firms. The purpose of this study is to delineate and contrast the market share performance of EMNEs, AMNEs and local firms in Africa.

The study used available longitudinal data (2013–2022) of six industries across four African countries from Euromonitor Passport, a rich, proprietary database.

Applying contingency theory, the study shows that, over time, there is no clear-cut winner in all markets and industries. Rather, market share gain is contingent on country and industry settings in Africa. Empirical analysis demonstrates that high-tech EMNE firms operating in Africa will exceed those of high-tech AMNEs and local firms. The findings also show that local firms generally performed better during the pandemic.

As Africa is a region of interest for scholars and practitioners, critical international business (IB) research contributions in Africa have predominantly focused on foreign investments from a particular nation. The present study enriches the literature by comparing the market share performance of AMNEs, EMNEs and local firms in this important region – during and prepandemic. The study offers theoretical and managerial implications for understanding the long-term performance of these three types of firms.

The purpose of this paper is to investigate how students in a Malaysian context, as a result of their experience of a Higher Education Institution (HEI) undergraduate teaching and learning experience in the subject of Marketing, perceive the knowledge, skills and competencies required of a practicing marketer and, conversely, what curriculum developers need to do if there is a “shortfall”.

Based on a total sample of a UG student population from an Accountancy, Finance and Business Faculty, the primarily descriptive, positivist, cross-sectional study used inferential statistics to measure the relationship between the four components of marketing knowledge, skills and competencies (the marketing mix, performance, social and emotional competencies, and responsible decision making).

Quantitative results revealed that all student perceptions of the requirements to be a “fit for purpose” marketer were highly correlated with requirements from the literature, subject benchmarks and practice with few exemptions.

The findings are based on one institution. Moreover, knowledge, skills and competency requirements by students’ level of study and practitioner experience may vary by type of HEI, organisation and geographic location.

Recommendations are made for curriculum development to address both employability and career development, particularly in terms of interdisciplinary co-operation and the teaching and learning of concepts.

Using the student perceptions of the requirements for being a practicing marketer, HEIs can adjust/add to their curriculum by comparing these to documented sources from academia and practice and by making any necessary adjustments by course of study.