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An exact multiple‐level dynamic substructure technique was developed by a combination of WYD algorithm and static multiple‐level substructuring technique. This method is essentially different from the traditional mode component synthesis. The eigenvalues and eigenvectors created by the method are the eigenpairs for the whole structure and not for the components of structure. On the other hand, the dynamic response by using mode superposition can also be implemented in substructure level. This algorithm actually is an exact substructuring technique which means that substructuring itself did not introduce any additional error except the round‐off when a structure was split into some arbitrary subdomains and the error of WYD or mode superposition themselves. It is no longer necessary to assume any connective condition on the interface between substructures. This method makes the capacity of dynamic analysis of a structural analysis program unlimited. It is especially attractive for the programs on microcomputers. Of course, the method leads to a frequent I/O for a subsequent search of the files from each substructure. It is time consuming compared to the mode component synthesis. But the potential still exists to improve the efficiency by using parallel computation on concurrent computers. In this paper the theory and procedure of the algorithm are presented.

The purpose of this paper is to apply the novel instantaneous power flow balance (IPFB)-based identification strategy to a specific practical situation like nonlinear lap joints having single and double bolts. The paper also investigates the identification performance of the proposed power flow method over conventional acceleration-matching (AM) methods and other methods in the literature for nonlinear identification.

A parametric model of the joint assembly formulated using generic beam element is used for numerically simulating the experimental response under sinusoidal excitations. The proposed method uses the concept of substructure IPFB criteria, whereby the algebraic sum of power flow components within a substructure is equal to zero, for the formulation of an objective function. The joint parameter identification problem was treated as an inverse formulation by minimizing the objective function using the Particle Swarm Optimization (PSO) algorithm, with the unknown parameters as the optimization variables.

The errors associated with identified numerical results through the instantaneous power flow approach have been compared with the conventional AM method using the same model and are found to be more accurate. The outcome of the proposed method is also compared with other nonlinear time-domain structural identification (SI) methods from the literature to show the acceptability of the results.

In this paper, the concept of IPFB-based identification method was extended to a more specific practical application of nonlinear joints which is not reported in the literature. Identification studies were carried out for both single-bolted and double-bolted lap joints with noise-free and noise-contamination cases. In the current study, only the zone of interest (substructure) needs to be modelled, thus reducing computational complexity, and only interface sensors are required in this method. If the force application point is outside the substructure, there is no need to measure the forcing response also.

The latest release of the stress analysis finite element system BERSAFE contains a new general substructuring facility for use in either elastic or non‐linear analysis. The technique allows a considerable extension to the available facilities in that parts of the structure can be stored on datafiles for current or subsequent use. In the latter case, repeated computations are avoided for components with identical geometric and material properties, so effectively larger problems can be solved without a proportional increase in cost and effort. For non‐linear analysis, the technique is well suited to cases where non‐linear behaviour is confined to certain parts of the structure, such as in the vicinity of stress concentrations and crack tips. The elastic areas can be replaced by a substructure boundary, thereby concentrating the analysis on the higher‐stressed portions of the structure and so reducing the extent and cost of each iteration. The non‐linear substructuring technique is described in detail and illustrated by examples.

The purpose of this paper is to bridge the gap by addressing the substructures of perceived knowledge quality (PKQ) drawn upon the theory of sensemaking. It also examines interactions of the substructures which, in turn, have differing impacts on innovativeness. Additionally, this study illustrates which PKQ substructure is most affected by knowledge sharing. PKQ has become imperative, not an option, for innovativeness in the environment characterized by knowledge overload. However, there is little research on PKQ due to its abundant, variable nature.

The survey methodology was used to collect data. A total of 368 individuals in the USA participated in the study. The partial least squares analysis for structural equation modeling was used to test the research model.

Perceived intrinsic knowledge quality is most affected by knowledge sharing, while knowledge sharing is a critical determinant of three PKQ substructures (i.e. perceived intrinsic, contextual and actionable knowledge quality). Perceived intrinsic knowledge quality, however, is inadequate by itself and should be transformed into perceived contextual, actionable knowledge quality to produce innovativeness.

This study addresses the shortfall of understanding the dynamics of PKQ’s substructures and unfolds theoretical links to knowledge sharing and innovativeness.

This study offers valuable insights to managers who face ongoing challenges in sharing knowledge and improving knowledge quality, thereby leading their quality of knowledge into innovativeness.

Despite growing recognition, few empirical studies on PKQ are present in the literature. This study contributes to understanding a holistic view of PKQ and its substructures with unique relationships by knowledge sharing and innovativeness.

This study aims to propose a vertical coupling dynamic analysis method of vehicle–track–substructure based on forced vibration and use this method to analyze the influence on the dynamic response of track and vehicle caused by local fastener failure.

The track and substructure are decomposed into the rail subsystem and substructure subsystem, in which the rail subsystem is composed of two layers of nodes corresponding to the upper rail and the lower fastener. The rail is treated as a continuous beam with elastic discrete point supports, and spring-damping elements are used to simulate the constraints between rail and fastener. Forced displacement and forced velocity are used to deal with the effect of the substructure on the rail system, while the external load is used to deal with the reverse effect. The fastener failure is simulated with the methods that cancel the forced vibration transmission, namely take no account of the substructure–rail interaction at that position.

The dynamic characteristics of the infrastructure with local diseases can be accurately calculated by using the proposed method. Local fastener failure will slightly affect the vibration of substructure and carbody, but it will significantly intensify the vibration response between wheel and rail. The maximum vertical displacement and the maximum vertical vibration acceleration of rail is 2.94 times and 2.97 times the normal value, respectively, under the train speed of 350 km·h⁻¹. At the same time, the maximum wheel–rail force and wheel load reduction rate increase by 22.0 and 50.2%, respectively, from the normal value.

This method can better reveal the local vibration conditions of the rail and easily simulate the influence of various defects on the dynamic response of the coupling system.

Purpose—The notion of organizations as gendered is not new, yet critical gaps in the understanding of the processes responsible for the creation and maintenance of these gendered organizations still exist. Within the existing breadth and depth of feminist organizational scholarship, an increasing number of researchers have been drawn to Joan Acker’s notion of the “gendered substructure” as one of the more promising frameworks for analysis of the gendering of organizations. In this chapter, the authors seek to develop an analysis of Acker’s gendered substructure through, and reflection on, its application.

Design/methodology/approach—Acker’s framework of gendering processes is explored through a case study of the gendering of a single organization over time—Pan American World Airways (Pan Am). The authors’ “reading” of the archival materials was informed by a combination of feminist poststructuralism, critical discourse analysis, and critical hermeneutics.

Findings—Through an exploration of the roots of Acker’s framework and its application to a case study of a single organization over time (Pan Am), the chapter contends that its greatest potential lies in examining the four process sets—division of labor, workplace culture, social interactions, and (self) reflection—through a fifth process of “organizational logic” that is seen as temporal and contextual. Drawing on poststructuralist feminist theory, it argues that organizational logic can be viewed through analyses of organizational, and organizationally based, discourses.

Originality/value—The chapter argues that the (widely recognized) heuristic value of Joan Acker’s “gendered substructure” has not been realized due to inconsistencies in its interpretation and application. This study engages Acker’s framework in its entirety, as gendering processes do not exist in silos and are likely more interdependent than typically credited. The chapter looks at the dynamics of, and between the five sets of, gendering processes.

The notion of organizations as gendered is not new yet critical gaps in the understanding of the processes responsible for the creation and maintenance of these gendered organizations still exist. Within the existing breadth and depth of feminist organizational scholarship an increasing number of researchers have been drawn to Joan Acker's notion of the “gendered substructure” as one of the more promising frameworks for analysis of the gendering of organizations. In this paper the authors seek to develop an analysis of Acker's gendered substructure through, and reflection on, its application.

Acker's framework of gendering processes is explored through a case study of the gendering of a single organization over time – Pan American World Airways (Pan Am). The authors' “reading” of the archival materials was informed by a combination of feminist poststructuralism, critical discourse analysis and critical hermeneutics.

Through an exploration of the roots of Acker's framework and its application to a case study of a single organization over time (Pan Am), the paper contends that its greatest potential lies in examining the four process sets – division of labor, workplace culture, social interactions and (self) reflection – through a fifth process of “organizational logic” that is seen as temporal and contextual. Drawing on poststructuralist feminist theory, it argues that organizational logic can be viewed through analyses of organizational, and organizationally based, discourses.

The paper argues that the (widely recognized) heuristic value of Joan Acker's “gendered substructure” has not been realized due to inconsistencies in its interpretation and application. This study engages Acker's framework in its entirety, as gendering processes do not exist in silos and are likely more interdependent than typically credited. The paper looks at the dynamics of, and between the five sets of, gendering processes.

This paper deals with numerical techniques dedicated to the predictive calculation of complex structures undergoing medium‐frequency vibrations. This field presents challenging difficulties. The first difficulty is the development of an efficient computational method because with the traditional finite element method (FEM), as the frequency increases, it becomes more expensive to control the pollution error. The second difficulty is the availability of sufficiently realistic joint models to take into account damping phenomena because in vibration problems dissipation controls the magnitude of the response directly.

We use the Variational Theory of Complex Rays (VTCR), an approach which effectively avoids the difficulties encountered with traditional FE techniques. Using two‐scale shape functions which verify the dynamic equation and the constitutive relation within each substructure, the VTCR can be viewed as a means of expressing the power balance at the different interfaces between substructures in variational form. New joint models which include heterogeneous mass, stiffness and damping are introduced to deal with the second difficulty.

This paper focuses on a new, substructured version of the VTCR which enables us to separate the realistically modeled substructures from the less accurate joints. The equations of the substructures are enforced exactly, whereas the interface equations are verified approximately through the minimization of an L² residual. We show that this new formulation gives good results compared to the traditional VTCR or the FEM.

Although the examples presented in this paper are very simple, this new formulation shoult encounter no difficulties when dealing with more complex assemblies composed of several plates, beams, shells,…

This new, substructured VTCR approach provides more flexibility in the improvement of joint models, for example by carrying out experimental measurements on real structures.

Three commercially available chemical substructure databases are reviewed: Chemical Abstracts, Index Chemicus, and the SANSS file (Chemical Information System). Coverage and overlap of Chemical Abstracts and Index Chemicus are studied, as well as differences between Chemical Abstracts as mounted by two different vendors (STN International and Questel). Guidelines for determining the database/system of choice are given.

Hybrid simulation, which is a general technique for obtaining the seismic response of an entire structure, is an improvement of the traditional seismic test technique. In order to improve the analysis accuracy of the numerical substructure in hybrid simulation, the purpose of this paper is to propose an innovative hybrid simulation technique. The technique combines the multi-scale finite element (MFE) analysis method and hybrid simulation method with the objective of achieving the balance between the accuracy and efficiency for the numerical substructure simulation.

To achieve this goal, a hybrid simulation system is established based on the MTS servo control system to develop a hybrid analysis model using an MFE model. Moreover, in order to verify the efficiency of the technique, the hybrid simulation of a three-storey benchmark structure is conducted. In this simulation, a ductile column—represented by a half-scale scale specimen—is selected as the experimental element, meanwhile the rest of the frame is modelled as microscopic and macroscopic elements in the Abaqus software simultaneously. Finally, to demonstrate the stability and accuracy of the proposed technique, the seismic response of the target structure obtained via hybrid simulation using the MFE model is compared with that of the numerical simulation.

First, the use of the hybrid simulation with the MFE model yields results similar to those obtained by the fine finite element (FE) model using solid elements without adding excessive computing burden, thus advancing the application of the hybrid simulation in large complex structures. Moreover, the proposed hybrid simulation is found to be more versatile in structural seismic analysis than other techniques. Second, the hybrid simulation system developed in this paper can perform hybrid simulation with the MFE model as well as handle the integration and coupling of the experimental elements with the numerical substructure, which consists of the macro- and micro-level elements. Third, conducting the hybrid simulation by applying earthquake motion to simulate seismic structural behaviour is feasible by using Abaqus to model the numerical substructure and harmonise the boundary connections between three different scale elements.

In terms of the implementation of the hybrid simulation with the MFE model, this work is helpful to advance the hybrid simulation method in the structural experiment field. Nevertheless, there is still a need to refine and enhance the current technique, especially when the hybrid simulation is used in real complex engineering structures, having numerous micro-level elements. A large number of these elements may render the relevant hybrid simulations unattainable because the time consumed in the numeral calculations can become excessive, making the testing of the loading system almost difficult to run smoothly.

The MFE model is implemented in hybrid simulation, enabling to overcome the problems related to the testing accuracy caused by the numerical substructure simplifications using only macro-level elements.

This paper is the first to recognise the advantage of the MFE analysis method in hybrid simulation and propose an innovative hybrid simulation technique, combining the MFE analysis method with hybrid simulation method to strike a delicate balance between the accuracy and efficiency of the numerical substructure simulation in hybrid simulation. With the help of the coordinated analysis of FEs at different scales, not only the accuracy and reliability of the overall seismic analysis of the structure is improved, but the computational cost can be restrained to ensure the efficiency of hybrid simulation.