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This paper aims to present a novel hybrid time integration approach for efficient numerical simulations of multiscale problems involving interactions of electromagnetic fields with fine structures.

The entire computational domain is discretized with a coarse grid and a locally refined subgrid containing the tiny objects. On the coarse grid, the time integration of Maxwell’s equations is realized by the conventional finite-difference technique, while on the subgrid, the unconditionally stable Krylov-subspace-exponential method is adopted to breakthrough the Courant–Friedrichs–Lewy stability condition.

It is shown that in contrast with the conventional finite-difference time-domain method, the proposed approach significantly reduces the memory costs and computation time while providing comparative results.

An efficient hybrid time integration approach for numerical simulations of multiscale electromagnetic problems is presented.

This paper aims to provide a simple and accurate higher order predictor‐corrector integration which can be used in dynamic analysis and to compare it with the previous works.

The predictor‐corrector integration is defined by combining the higher order explicit and implicit integrations in which displacement and velocity are assumed to be functions of accelerations of several previous time steps. By studying the accuracy and stability conditions, the weighted factors and acceptable time step are determined.

Simplicity and vector operations plus accuracy and stability are the main specifications of the new predictor‐corrector method. This procedure can be used in linear and nonlinear dynamic analysis.

In the proposed integration, time step is assumed to be constant.

The numerical integration is the heart of a dynamic analysis. The result's accuracy is strongly influenced by the accuracy and stability of the numerical integration.

This paper presents simple and accurate predictor‐corrector integration based on accelerations of several previous time steps. This may be used as a routine in any dynamic analysis software to enhance accuracy and reduce computational time.

The time‐discretization process of transient equation systems is an important concern in computational heat transfer applications. As such, the present paper describes a formal basis towards providing the theoretical concepts, evolution and development, and characterization of a wide class of time discretized operators for transient heat transfer computations. Therein, emanating from a common family tree and explained via a generalized time weighted philosophy, the paper addresses the development and evolution of time integral operators [IO], and leading to integration operators [InO] in time encompassing single‐step integration operators [SSInO], multi‐step integration operators [MSInO], and a class of finite element in time integration operators [FETInO] including the relationships and the resulting consequences. Also depicted are those termed as discrete numerically assigned [DNA] algorithmic markers essentially comprising of both: the weighted time fields, and the corresponding conditions imposed upon the dependent variable approximation, to uniquely characterize a wide class of transient algorithms. Thereby, providing a plausible standardized formal ideology when referring to and/or relating time discretized operators applicable to transient heat transfer computations.

Post-merger integration (PMI) is driven by coevolving processes. By integrating the literature on acquisitions with that of knowledge networks, this paper highlights different reconstruction mechanisms for dual knowledge networks during PMI – namely, internal knowledge network coupling and external knowledge network embeddedness. This paper aims to examine their coevolutionary relationships with PMI.

A coevolutionary framework is tested using a latent growth model and cross-lagged models. The analysis is based on longitudinal data collected from 116 Chinese technology-sourcing overseas merger and acquisition firms.

This paper unearths a novel idea that variations in post-merger reconstruction of dual knowledge networks can explain why some acquirers increase the degree of integration faster than the others. The results show that the internal knowledge network coupling leads to more knowledge similarity and, in turn, causes a higher degree of integration. The external knowledge network embeddedness also causes higher relative network status of the acquirer, which consequently leads to a higher degree of integration. Furthermore, results from cross-lagged models confirm that an increase in the degree of integration positively influences subsequent changes in the internal knowledge network coupling and external knowledge network embeddedness, thus forming a coevolutionary relationship over time.

This paper responds to recent calls for more insights into the dynamics of PMI. By highlighting different reconstruction mechanisms for internal and external knowledge networks during PMI, this paper explains why it is important to understand PMI dynamics from a dual knowledge network perspective. This paper is the first to adopt a coevolutionary perspective and provide a more comprehensive dynamic framework between PMI and reconstruction of dual knowledge networks. Besides, this paper contributes to the research on emerging market multinational corporations’ cross-border merger and acquisition integration from a dynamic perspective, revealing the time effects of traditionally favored light-touch integration.

The distinct element method as proposed by Cundall and Strack uses the computationally efficient, explicit, central difference time integration scheme. A limitation of this scheme is that it is only conditionally stable, so small time steps must be used. Some researchers have proposed using an implicit time integration scheme to avoid the stability issues arising from the explicit time integrator typically used in these simulations. However, these schemes are computationally expensive and can require a significant number of iterations to form the stiffness matrix that is compatible with the contact state at the end of each time step. In this paper, a new, simple approach for calculating the critical time increment in explicit discrete element simulations is proposed. Using this approach, it is shown that the critical time increment is a function of the current contact conditions. Considering both two‐ and three‐dimensional scenarios, the proposed refined estimates of the critical time step indicate that the earlier recommendations contained in the literature can be unconservative, in that they often overestimate the actual critical time step. A three‐dimensional simulation of a problem with a known analytical solution illustrates the potential for erroneous results to be obtained from discrete element simulations, if the time‐increment exceeds the critical time step for stable analysis.

The purpose of this paper is to investigate the merger arranged in the audiovisual sector between Antena 3 and La Sexta, and specifically the pre- and post-merger factors. This study adopts a comprehensive approach for the analysis of the reasons behind this strategic decision and the role that structural and human integration and the decision on the right momentum and integration speed played in the merger success.

A single case study research method is used. This qualitative methodology provides richer data to understand complex transactions such as mergers and acquisitions (M&As). According to the data triangulation technique, two research methods were used, in-depth interviews and archival secondary data, including confidential reports and archival trade press.

The merger involving Antena 3’s takeover of La Sexta in October 2012 has been seen as one of the most successful operations ever undertaken in Spain’s audiovisual industry. The main motivation was to increase the organisation’s size to make it more competitive in the market, thus reducing costs, generating synergies and improving performance. Structural and human integration has provided the backbone for this success, all at a time marked by the global financial crisis and its knock-on effect on the downturn in the advertising market. Another of the key factors of success was that the changes in the organisational systems and processes were designed and partially implemented before the incorporation of La Sexta.

This work has highlighted the need for proper planning and a suitable choice of timing in M&A operations. Management should pay special attention to the integration of human and productive resources to generate synergies on the road to success.

This paper’s main contribution is to highlight an example of a successful M&A in the audiovisual sector in Spain by adopting a holistic perspective. While there are scarce studies in this industry, previous research on this topic is mostly quantitative and, moreover, the rate of success in M&A is quite low.

While existing literature extensively explores manufacturing firms expanding into services, little is known about the modes of servitisation, the means by which they carry it out. This paper concentrates on acquisitions as a mode of servitisation. Post-acquisition integration is when the potential of an acquisition is realised. The paper therefore aims to categorise types of integrations following the acquisition of servitised firms and discusses their consequences for servitisation.

The empirical part of the paper is based on two case studies, each involving the acquisition of servitised firms. Both acquirers changed their integration approach over time.

The paper conceptualises three types of integrations: rhetorical, insulated and transformative integrations, indicating whether and how the acquirer becomes servitised following the integration. These highlight the analysis of integration based on business models and customer orientation in relation to servitisation.

This paper contributes to research on servitisation by emphasising acquisitions as a mode of servitisation and conceptualising three integration types related to business models and customer orientations. Furthermore, the paper highlights how an acquirer's servitisation leads to new offerings targeting new customers, as opposed to strengthening existing relationships.

The purpose of this paper is to report the implementation of an alternative time integration procedure for the dynamic non-linear analysis of structures.

The time integration algorithm discussed in this work corresponds to a spectral decomposition technique implemented in the time domain. As in the case of the modal decomposition in space, the numerical efficiency of the resulting integration scheme depends on the possibility of uncoupling the equations of motion. This is achieved by solving an eigenvalue problem in the time domain that only depends on the approximation basis being implemented. Complete sets of orthogonal Legendre polynomials are used to define the time approximation basis required by the model.

A classical example with known analytical solution is presented to validate the model, in linear and non-linear analysis. The efficiency of the numerical technique is assessed. Comparisons are made with the classical Newmark method applied to the solution of both linear and non-linear dynamics. The mixed time integration technique presents some interesting features making very attractive its application to the analysis of non-linear dynamic systems. It corresponds in essence to a modal decomposition technique implemented in the time domain. As in the case of the modal decomposition in space, the numerical efficiency of the resulting integration scheme depends on the possibility of uncoupling the equations of motion.

One of the main advantages of this technique is the possibility of considering relatively large time step increments which enhances the computational efficiency of the numerical procedure. Due to its characteristics, this method is well suited to parallel processing, one of the features that have to be conveniently explored in the near future.

The great magnitude differences between the integral tunnel and its structure details make it impossible to numerically model and analyze the global and local seismic behavior of large-scale shield tunnels using a unified spatial scale, even with the help of supercomputers. The paper aims to present a combined equivalent & multi-scale simulation method, by which the tunnel's major mechanical properties under seismic loads can be represented by the equivalent model, and the seismic responses of the interested details can be studied efficiently by the coupled multi-scale model.

The nominal orthotropic material constants of the equivalent tunnel model are inversely determined by fitting the modal characteristics of the equivalent model with the corresponding segmental lining model. The critical sections are selected by comprehensive analyzing of the integral compression/extension and bending loads in the equivalent lining under the seismic shaking and the coupled multi-scale model containing the details of interest is solved by the mixed time explicit integration algorithm.

The combined equivalent & multi-scale simulation method is an effective and efficient way for seismic analyses of large-scale tunnels. The response of each flexible joint is related to its polar location on the lining ring, and the mixed time integration method can speed-up the calculation process for hybrid FE model with great differences in element sizes.

The orthotropic equivalent assumption is, to the best of the authors’ knowledge, for the first time, used in the 3D simulation of the shield tunnel lining, representing the rigidity discrepancies caused by the structural property.

This paper proposes to extend the combination of Extended Finite Element Method (XFEM) and Level Set Method (LSM) from structural mechanics to electromagnetics. Based on this approach, the actual stage of the research work, dedicated to the investigation, development, implementation and validation of a shape optimization methodology, particularly tailored for 2D electric structures is described.

The proposed numerical approach is based on the efficiency of the XFEM and the flexibility of the LSM, to handle moving material interfaces without remeshing the whole studied domain at each optimization step.

This approach eliminates the conventional use of discrete finite elements and provides efficient, stable, accurate and faster computation schemes in comparison with other methods.

This research is limited to shape optimization of two‐dimensional electric structures, however, the work can be extended to 3D ones too.

The implementation of the proposed numerical approach for the shape optimization of a planar resistor is hereby described.

The main value of the proposed approach is a powerful and robust numerical shape optimization algorithm that demonstrates outstanding suppleness of handling topological changes, fidelity of boundary representation and a high degree of automation in comparison with other methods.