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The safety and reliability of high-speed trains rely on the structural integrity of their components and the dynamic performance of the entire vehicle system. This paper aims to define and substantiate the assessment of the structural integrity and dynamical integrity of high-speed trains in both theory and practice. The key principles and approaches will be proposed, and their applications to high-speed trains in China will be presented.

First, the structural integrity and dynamical integrity of high-speed trains are defined, and their relationship is introduced. Then, the principles for assessing the structural integrity of structural and dynamical components are presented and practical examples of gearboxes and dampers are provided. Finally, the principles and approaches for assessing the dynamical integrity of high-speed trains are presented and a novel operational assessment method is further presented.

Vehicle system dynamics is the core of the proposed framework that provides the loads and vibrations on train components and the dynamic performance of the entire vehicle system. For assessing the structural integrity of structural components, an open-loop analysis considering both normal and abnormal vehicle conditions is needed. For assessing the structural integrity of dynamical components, a closed-loop analysis involving the influence of wear and degradation on vehicle system dynamics is needed. The analysis of vehicle system dynamics should follow the principles of complete objects, conditions and indices. Numerical, experimental and operational approaches should be combined to achieve effective assessments.

The practical applications demonstrate that assessing the structural integrity and dynamical integrity of high-speed trains can support better control of critical defects, better lifespan management of train components and better maintenance decision-making for high-speed trains.

Extends the evolutionary structural optimization method to the solution for the natural frequency optimization of a two‐dimensional structure with additional non‐structural lumped masses. Owing to the significant difference between a static optimization problem and a structural natural frequency optimization problem, five basic criteria for the evolutionary natural frequency optimization have been established. The inclusion of these criteria into the evolutionary structural optimization method makes it possible to solve structural natural frequency optimization problems for two‐dimensional structures with additional non‐structural lumped masses. Gives two examples to demonstrate the feasibility of the extended evolutionary structural optimization method when it is used to solve structural natural frequency optimization problems.

Considering the randomness of physical parameters of structural material, dynamic characteristic topology optimization mathematical model based on reliability of planar continuum structures is built in this paper. In which topology information variables of the structure are taken as design variables, minimizing the mean value of total structural weight as objective function and satisfying the reliability requirement of structural dynamic characteristic as constraints. In the process of optimization, the ESO method based on probability is adopted as solution strategy. At the same time, distribution function method is utilized to convert the reliability constraints into conventional constraints formally. A square thin plate with four sides fixed is used as an example to demonstrate the rationality and validity of the presented model.

This study analyzes strategic flexibility with a two-dimensional approach (structural and decisional flexibility). It also investigates the relationships among competitive strategy, structural flexibility, decisional flexibility, and financial and nonfinancial performance.

The authors collected data from members of 16 chambers of commerce in the United States and used PLS-SEM (partial least squares structural equation modeling) to test the hypotheses.

The findings suggest that strategic flexibility impacts financial and nonfinancial performance in different ways. While financial performance is influenced by both the structural and decisional dimensions of strategic flexibility, nonfinancial performance is impacted only by structural flexibility. In addition, the research indicates a negative relationship between cost leadership and structural flexibility and positions structural flexibility as a mediator between cost-leadership and nonfinancial performance.

The authors contribute to strategic flexibility research in the following ways: (1) analyzed the impact on nonfinancial performance; (2) examined structural and decisional elements and (3) identified cost leadership as a potential barrier.

The paper aims to develop an efficient data-driven modeling approach for the hydroelastic analysis of a semi-circular pipe conveying fluid with elastic end supports. Besides the structural displacement-dependent unsteady fluid force, the steady one related to structural initial configuration and the variable structural parameters (i.e. the variable support stiffness) are considered in the modeling.

The steady fluid force is treated as a pipe preload, and the elastically supported pipe-fluid model is dealt with as a prestressed hydroelastic system with variable parameters. To avoid repeated numerical simulations caused by parameter variation, structural and hydrodynamic reduced-order models (ROMs) instead of conventional computational structural dynamics (CSD) and computational fluid dynamics (CFD) solvers are utilized to produce data for the update of the structural, hydrodynamic and hydroelastic state-space equations. Radial basis function neural network (RBFNN), autoregressive with exogenous input (ARX) model as well as proper orthogonal decomposition (POD) algorithm are applied to modeling these two ROMs, and a hybrid framework is proposed to incorporate them.

The proposed approach is validated by comparing its predictions with theoretical solutions. When the steady fluid force is absent, the predictions agree well with the “inextensible theory”. The pipe always loses its stability via out-of-plane divergence first, regardless of the support stiffness. However, when steady fluid force is considered, the pipe remains stable throughout as flow speed increases, consistent with the “extensible theory”. These results not only verify the accuracy of the present modeling method but also indicate that the steady fluid force, rather than the extensibility of the pipe, is the leading factor for the differences between the in- and extensible theories.

The steady fluid force and the variable structural parameters are considered in the data-driven modeling of a hydroelastic system. Since there are no special restrictions on structural configuration, steady flow pattern and variable structural parameters, the proposed approach has strong portability and great potential application for other hydroelastic problems.

This study aims to explore how stakeholders leverage their guanxi and structural holes to promote knowledge mobilization to increase the performance of sci-tech achievement transformation.

This study conducted questionnaires, a social network analysis and semistructured interviews to examine its hypotheses by gathering data from a university and an enterprise in China.

Structural holes impede knowledge mobilization among stakeholders in their network, but guanxi moderates this impeding effect. In addition, knowledge mobilization promotes transformation performance.

By developing a mechanism to illustrate how stakeholders strategically leverage their guanxi and structural holes to affect the efficacy of knowledge mobilization to increase transformation performance, we reveal how stakeholders interact to co-create values for innovation, thereby contributing to the innovation and knowledge management literature.

This study aims to theorize and empirically examine how guanxi in Chinese collectivistic culture affects entrepreneurs to leverage the structural holes they occupy when it comes to promoting knowledge transfer.

To examine the hypotheses, this study used a mixed-methods research approach where quantitative questionnaires and social network analyses were used through 365 Chinese entrepreneurs, and qualitative semistructured interviews were conducted through 50 Chinese entrepreneurs.

In a Chinese entrepreneur’s guanxi network, structural holes will impede knowledge transfer among network members, but guanxi will moderate this impeding effect.

By revealing how “structural hole controllers” become “structural hole fillers” under the moderating influence of guanxi in Chinese collectivistic culture, this study recognizes the different roles that persons who occupy a structural hole play in different situations, which advances structural hole theory. In addition, by exploring how entrepreneurs orchestrate these structural holes to create a strong guanxi network that can be infinitely extended, this study reveals a means to achieve both advantages of bonding and bridging social capital simultaneously, which generates a theoretical contribution to social capital integration.

This study suggests Chinese entrepreneurs to cultivate guanxi to improve their needs in decision-making by giving renqing, returning renqing, earning mianzi and giving mianzi.

By showing how Chinese entrepreneurs leverage their guanxi and structural holes to facilitate knowledge transfer, this study identifies the critical entrepreneurial behavior that promotes business development, thereby contributing to the literature of knowledge management, entrepreneurship and social network.

This paper examines the nexus between supply chain social capital (relational social capital and structural social capital), supply chain responsiveness (operations system responsiveness and supplier network responsiveness) and firm performance. Additionally, the study examines the mediating role of supply chain responsiveness on the relationship between supply chain social capital and firm performance.

The authors test their hypotheses on a sample of 120 firms operating in Ghana. The measurement model and hypothesized paths were assessed using partial least squares structural equation modelling.

The findings revealed that structural social capital had a significant direct effect on firm performance, but relational social capital did not. It was also revealed that both relational and structural social capital have significant effects on operations system responsiveness and supplier network responsiveness. Additionally, operations system responsiveness fully mediated the effect of relational social capital on firm performance and partially mediated the effect of structural social capital on firm performance. Supplier network responsiveness, on the other hand, partially mediated the effect of both relational and structural social capital on firm performance.

This study contributes to the limited literature on supply chain social capital by unearthing the mechanisms through which supply chain social capital enhances firm performance. Specifically, the study demonstrates the intervening role of operations system responsiveness and supplier network responsiveness in the supply chain social capital–firm performance link.

The purpose of the paper is to compare the aesthetic responses of three groups (architects, engineers and non‐experts) to a set of non‐conventional structures.

A group of 150 respondents (divided into three equal sub‐groups of architects, structural engineers, and non‐experts) were selected to participate in the main study, which used 14 different non‐conventional structural systems. The images of these systems were derived from an earlier pilot study. The evaluation tool included 38 semantic items, also derived from the pilot study. Two statistical analyses were applied to the collected data: factor analysis and ANOVA.

Finds, first, that factor analysis revealed a set of factors identified by all participants as meaningful dimensions, by which they evaluate structural systems. Second, ANOVA revealed differences between the three groups when evaluating different structural systems using the identified factors. Differences between the groups were attributed to their different backgrounds and technical training.

The study argues that understanding the aesthetic experience of architects, engineers and ordinary users of structures is essential. First, it helps the designers to establish the basis for selecting appropriate structural methods and materials in relation to building design. Second, it would also help the designers to better understand the relationship between the structure and architecture in terms of a trade‐off between the technical and aesthetic issues. Third, it helps the designers to better understand how their designed structures are perceived by the public.

This study introduces an alternative approach to the study of the aesthetics of structures, with a focus on non‐conventional structures.

The purpose of this paper is to explore the relationship between advances in educational attainment on the one hand, and structural change in employment on the other, in four countries in Sub-Saharan Africa for selected periods.

The paper is based on a decomposition of changes in education intensity, which is complemented by an analysis of rates of return to education. For all countries the analysis is based on labour market microdata from nationally representative household surveys, and on economic data from national accounts.

It is demonstrated that if countries want to exploit structural change, levels of education need to rise. Low levels of education explain why the increase in educational attainment in Tanzania was barely sufficient to keep up with structural change in this country, and Mozambique would have been in the same situation if structural change would have occurred. In Ghana and Namibia, levels of educational attainment are much higher, and the paper demonstrates how education was used differently to accommodate structural change in these countries. Rates of return to education in all four countries appear consistent with patterns of education intensity.

The analysis demonstrates that labour market monitoring should not be limited to (broad) sectoral aggregates. The analysis of more detailed breakdowns of employment is needed to gain insights into economies and labour markets of countries, including with regard to the role of education.

The paper is original in that an identical methodology is used in four African countries to decompose changes in education intensity, to relate these changes to employment patterns and to calculate rates of return to education. Although such work has been undertaken in individual countries, it is rarely done in a comparative way.