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This paper aims to present a topology optimization (TopO) method for designing heat exchangers (HEx) with two working fluids to be kept apart. The introduction of cut–cells gives rise to the cut-cell TopO method, which computes the optimal distribution of an artificial impermeability field and successfully overcomes the weaknesses of the standard density-based TopO (denTopO) by computing the fluid–solid interface (FSI) at each cycle. This allows to accurately solve the flow and conjugate heat transfer (CHT) problem by imposing exact boundary conditions on the computed FSI and results to correct performances computed without the need to re-evaluate the optimized solutions on a body-fitted grid.

The elements of an artificial impermeability distribution field defined on a background grid act as the design variables and allow topological changes to take place. Post-processing them yields two fields indicating the location of the two flow streams inside the HEx. At each TopO cycle, the FSIs computed based on these two fields are used as the cutting surfaces of the cut-cell grid. On the so-computed grid, the incompressible Navier–Stokes equations, coupled with the Spalart–Allmaras turbulence model, and the temperature equation are solved. The derivatives of the objective and constraint functions with respect to the design variables of TopO are computed by the continuous adjoint method, using consistent discretization schemes devised thanks to the “Think Discrete – Do Continuous” (TDDC) adjoint methodology.

The effectiveness of the cut-cell–based TopO method for designing HEx is demonstrated in 2D parallel/counter flow and 3D counter flow HEx operating under both laminar and turbulent flow conditions. Compared to the standard denTopO, its ability to compute FSIs along which accurate boundary conditions are imposed, increases the accuracy of the flow solver, which usually leads to optimal, rather than sub-optimal, solutions that truly satisfy the imposed constraints.

This work proposes a new/complete methodology for the TopO of two-fluid systems including CHT that relies on the cut-cell method. This successfully combines aspects from both TopO and Shape Optimization (ShpO) in a single framework thus overcoming the well-known downsides of standard denTopO regarding its accuracy or the need for a follow-up ShpO after TopO. Instead of adding the well-known Brinkman penalization terms into the flow equations, it computes the FSIs at each optimization cycle allowing the solution of the CHT problem on a cut-cell grid.

To provide a holistic assessment of tourists’ staycation intentions, this study aims to investigate the role of secondary-stakeholder corporate social responsibility (CSR) on local engagement. Based on construal-level theory and stimulus-organism-response model, this study unpacks how and when secondary-stakeholder CSR influences staycation intention.

Data were gathered from 312 Chinese tourists with prior staycation experiences. Data were subsequently analyzed using structural equation modeling.

This study illuminates that secondary-stakeholder CSR positively influences staycation intention directly and indirectly through psychological belonging and safety. Noteworthily, immersive experience strengthens the influence of psychological belonging on staycation intention while its effect on the relationship between psychological safety and staycation intention is negligible.

All variables in this study were collected via self-report measures provided by hotel customers with staycation experiences. Although both statistical and procedural remedies are used, it would be more useful if future studies could gather time-lagged and/or multiple sources of data.

This study augments the domain of staycation research by examining CSR marketing through a stakeholder perspective. This nuanced analysis elucidates the intertwined dynamics among secondary-stakeholder CSR, psychological sense of belonging and safety, and immersive experiences that delineate the landscape of staycation markets, casting light on their epoch-defining implications for hotels’ developmental trajectories.

Literature on teacher leadership highlights a significant gap in understanding the role of teacher leaders (TLs) as entrepreneurs. This research aims to bridge this gap by examining the multifaceted entrepreneurial dimension of teacher leadership. It specifically focuses on providing a comprehensive profile of these leaders and assessing their perceived influence on teachers’ outcome, which are important for improving school performance.

A two-step clustering procedure was utilized to discern profiles of teacher leaders’ entrepreneurial behaviours, sampling 586 participants in a teacher leader training program. To assess mean differences in relation to perceived influence on teacher outcomes (i.e. job satisfaction, intrateam trust and innovative teaching practices) among these clusters, two-way contingency table analysis and MANOVA were conducted.

We identified three teacher-leader profiles: congenial facilitators, champion-leaders and executors. Our findings reveal the unique strengths and weaknesses of each profile and their contributions to job satisfaction, intrateam trust and innovative teaching practices.

This study is innovative in its detailed examination of teacher leadership through the lens of Teacher Entrepreneurial Behaviour (TEB), providing new perspectives on the intricate relationships between teacher leaders' TEB and their perceived influences. This deeper insight emphasizes the important role of entrepreneurial behaviours within teacher leadership, suggesting new directions for further research and development in educational leadership practices.

Framed by social cognition theory, this study examines the impact of environmental factors (e.g. social norms) on students’ entrepreneurial self-efficacy (ES) and entrepreneurial intention (EI).

We obtained responses to a survey from 811 senior secondary students in Hong Kong. We then employed structural equation modeling (SEM) to test the proposed hypothesis. We removed non-significant parameters in testing the model and obtained the final SEM.

Among these students, those who were male or spoke English at home showed stronger social norms of entrepreneurship and greater entrepreneurial SE, which was linked to greater EI. Among students perceiving stronger social norms of entrepreneurship, those who lived in private housing or spoke English at school showed greater entrepreneurial intention.

The study provides a new social cognitive perspective for examining EI that emphasizes learning and development through the interaction of environmental and cognitive factors. It supplements previous research by demonstrating the significant influence of social norms and the conditional role of parental influence, adding complexity to our understanding of how these factors' interplay.

The article focuses on cross-sectoral analysis concerning services, especially ICT services, flowing from China to European manufacturing. The aim of the study is to analyse Sino-European relations in terms of ICT servicification. The article attempts to answer the following questions: does China’s relationship with Europe in terms of the servicification of manufacturing align with global servicification trends? Have global economic shocks, such as decoupling policies, diminished the flows of Chinese ICT services in European advanced manufacturing sectors?

This study employed input–output models to analyse the increasing role of China as a supplier of ICT services to European manufacturing. It also identified the industries that are most dependent on Chinese ICT services.

The analysis highlights the increasing reliance of European manufacturing on Chinese ICT services, with a notable rise across both Western Europe and CEE. This dependency is particularly strong in advanced sectors such as automotive and electronics, and there is no evidence of decoupling from China, even amidst global shocks or geopolitical tensions like the Trump presidency. Additionally, the BRI had limited direct impact, as the servicification trends appear driven more by broader globalization processes.

The study investigates all European countries and their manufacturing sectors’ reliance on Chinese services. It concentrates on services related to high technology, specifically ICT. Moreover, the previous research has focused on servicification of manufacturing, in general, neglecting industry-specific analysis. It contributes to the literature by providing insights into the relationships between developing and developed economies in terms of GVCs in the context of digital servicification and decoupling conditions.

This article investigates the impact of consumers’ promotion strategies on the effectiveness of promotional campaigns for subscribing to Over-the-Top (OTT) streaming services, from a prospective theoretical perspective. Additionally, it explores the moderating effects of platform type and subscriber type on promotion strategies in the context of OTT streaming services.

This study employs an experimental design to separately examine the promotion strategies of subscribers. The first part investigates the effect of promotion strategies on promotional effectiveness, regardless of platform and subscriber types, while the second part considers the moderating effects of both platform type and subscriber type on promotional effectiveness.

The analysis reveals that renewed subscribers exhibit a positive attitude toward incremental promotions and have stronger intentions to subscribe and recommend. Nonrenewed subscribers, in contrast, prefer discount promotions, demonstrating a positive attitude toward them and expressing higher intentions to subscribe and recommend.

This study applies prospect theory to OTT promotion strategies, uncovers the psychological drivers behind promotion effectiveness and examines the moderating role of subscriber type and platform type, thereby providing actionable insights to improve consumers’ attitudes and behavioral intentions.

A transmission tower usually experiences bolt loosening under long-term alternating cyclic load, which may lead to collapse of the tower in extreme operating conditions. The paper aims to propose a data-driven identification method for bolt looseness of complicated tower structures based on reduced-order models and numerical simulations to perceive and evaluate the health state of a tower in operation.

The equivalent stiffnesses of three types of bolt joints under various loosening scenarios are numerically determined by three-dimensional finite element (FE) simulations. The order of the FE model of a tower structure with bolt loosening is reduced by means of the component modal synthesis method, and the dynamic responses of the reducer-order model under calibration loads are simulated and used to create the dataset. An identification model for bolt looseness of the tower structure based on convolutional neural networks driven by the acceleration sensors is constructed.

An identification model for bolt looseness of the tower structure based on convolutional neural networks driven by the acceleration sensors is constructed and the applicability of the model is investigated. It is shown that the proposed method has a high identification accuracy and strong robustness to data noise and data missing. Meanwhile, the method is less dependent on the number and location of sensors and is easier to apply in real transmission lines.

This paper proposes a data-driven identification method for bolt looseness of a complicated tower structure based on reduced-order models and numerical simulations. Non-linear relationships between equivalent stiffness of bolted joints and bolt preload depicting looseness are obtained and reduced-order model of tower structure with bolt looseness is established. Finally, this paper investigates applicability of identification model for bolt looseness.

This study investigates the role of interlocking director networks (IDN) in driving corporate digital transformation (CDT) and explores the moderating role of agency costs, diversification and financial distress.

The analysis uses data from Chinese A-share listed companies on the Shanghai and Shenzhen stock exchanges from 2006 to 2021. A two-way fixed-effects model is employed to assess the impact of IDNs on CDT.

The results indicate that IDNs positively affect CDT. Furthermore, this effect is enhanced by agency costs and financial distress, while diversification acts as a negative moderator.

Informal institutions such as IDNs play a significant role in corporate governance in China’s relational society. This study focuses on the influence of informal institutions on digital transformation, expanding the understanding of the economic consequences of IDNs and enriching the literature on factors influencing digital transformation.

The cable inspection robot is essential in maintaining bridge cables. The purpose of this paper is to summarize the maintenance methods of bridge cables. It summarizes the advantages and disadvantages of the critical structures of the external overall frame, intermediate adhesion device, attachment mechanism and driving method of the cable inspection robot. Finally, it discusses the challenges the cable inspection robot faces and the direction of future research.

This paper summarizes the research progress of the cable inspection robot and details the advantages and disadvantages of critical structures such as the external frame, intermediate adhesion device, attachment mechanism, driving method and safe return device of the robot. Finally, it points out the future direction of cable inspection robots, including lightweight design, hybrid design, multi-robot cooperative work, multi-technology integration and intelligent cable inspection digital twin model.

The cables are the main load-bearing components of a bridge, and their safety is crucial. However, subjected to varying loads and environmental influences over a long period, cables are prone to damage, threatening the bridge’s stability. Cable inspection robots can comprehensively detect and repair cable damage, significantly improving efficiency and safety.

This paper provides a comprehensive review of the current research on cable inspection robots, enabling readers to have a comprehensive and systematic understanding of the critical structures and key technologies of cable inspection robots and providing scientific references for researchers working on cable inspection robots.

The emerging live streaming technology has provided a novel means for streamers to interact with viewers, allowing for synchronous and vivid demonstrations of products for sale. However, individual streamers as sellers still struggle to improve sales in their live stores. Drawing upon flow theory, our study proposes and tests a moderated-mediation model that explores (1) the indirect influences of telepresence and social presence as two important live streaming affordances on viewers’ purchase intentions through the immersive state of flow and (2) the dynamic contingency embedded in the indirect relationships between presence and purchases through flow as created by mindfulness.

We collected survey data from 251 experienced consumers of a three-year Kuaishou store run by an Inner Mongolian singer in China. We applied a covariance-based structural equation modeling approach to examine the first-stage moderated-mediation model.

Our results show that viewers’ flow state mediated the effects of telepresence and social presence on purchase intentions of both virtual gifts and physical products. Additionally, mindfulness toward live streaming strengthened the mediation effect of flow on the relationship between telepresence and purchase intentions but weakened its mediation effect between social presence and purchase intentions.

Our study not only expands the existing knowledge on live commerce but also systematically addresses the theoretical tension between flow and mindfulness as two important user states that coexist in the live commerce context. Our findings also reveal practical implications for streamers, managers and designers of live commerce.