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This article aims to present a direct solution to handle linear constraints in finite element (FE) analysis without penalties or the Lagrange multipliers introduced.

First, the system of linear equations corresponding to the linear constraints is solved for the leading variables in terms of the free variables and the constants. Then, the reduced system of equilibrium equations with respect to the free variables is derived from the finite-dimensional virtual work equation. Finally, the algorithm is designed.

The proposed procedure is promising in three typical cases: (1) to enforce displacement constraints in any direction; (2) to implement local refinements by allowing hanging nodes from element subdivision and (3) to treat non-matching grids of distinct parts of the problem domain. The procedure is general and suitable for 3D non-linear analyses.

The algorithm is fitted only to the Galerkin-based numerical methods.

The proposed procedure does not need Lagrange multipliers or penalties. The tangential stiffness matrix of the reduced system of equilibrium equations reserves positive definiteness and symmetry. Besides, many contemporary Galerkin-based numerical methods need to tackle the enforcement of the essential conditions, whose weak forms reduce to linear constraints. As a result, the proposed procedure is quite promising.

This paper aims to assess the feasibility of additively manufactured wind tunnel models. The additively manufactured model was used to validate a computational framework allowing the evaluation of the performance of five wing models.

An optimized fighter wing was additively manufactured and tested in a low-speed wind tunnel to obtain the aerodynamic coefficients and deflections at different speeds and angles of attack. The flexible wing model with optimized curvilinear spars and ribs was used to validate a finite element framework that was used to study the aeroelastic performance of five wing models. As a computationally efficient optimization method, homogenization-based topology optimization was used to generate four different lattice internal structures for the wing in this study. The efficiency of the spline-based optimization used for the spar-rib model and the lattice-based optimization used for the other four wings were compared.

The aerodynamic loads and displacements obtained experimentally and computationally were in good agreement, proving that additive manufacture can be used to create complex accurate models. The study also shows the efficiency of the homogenization-based topology optimization framework in generating designs with superior stiffness.

To the best of the authors’ knowledge, this is the first time a wing model with curvilinear spars and ribs was additively manufactured as a single piece and tested in a wind tunnel. This research also demonstrates the efficiency of homogenization-based topology optimization in generating enhanced models of different complexity.

Based on the conservation of resource theory, this paper explores the impact of differentiated transformational leadership on employees' taking charge in the context of Chinese organizations, with psychological availability as a mediator and collectivism orientation as a moderator.

The authors distributed paired questionnaires to 67 team managers and 219 team members to obtain research data and established a hierarchical linear model for the hypothesis testing.

The results show that team-focus transformational leadership has a significant positive impact on employees' taking charge, and individual-focus transformational leadership has a significant negative impact on employees' taking charge. Specifically, psychological availability plays a partial mediating role between differentiated transformational leadership and employees' taking charge. Moreover, collectivism orientation has no significant moderating effect between team-focus transformational leadership and psychological availability. But it has a significant moderating effect between individual-focus transformational leadership and psychological availability, i.e. the higher the level of collectivism orientation, the stronger the negative effect of individual-focus transformational leadership on psychological availability.

The paper notes the hierarchy of differentiated transformational leadership and divides it into team-focus transformational leadership and individual-focus transformational leadership. It also provides a new mechanism and boundary condition, i.e. differentiated transformational leadership has an impact on employees' taking charge through psychological availability and collectivism orientation is a moderator.

This paper examined the mediating role of boundary spanning behavior and the moderating effects of traditionality linking humble leadership and employee creative performance from the perspective of Social Exchange Theory (SET) to reveal the behavioral mechanism and boundary condition regarding the influence of humble leadership on creative performance.

A sample of 276 employees and the supervisors from 8 companies in China was taken using two-wave data.

The results indicated that humble leadership was positively related to employee creative performance, and boundary spanning behavior partially mediated the relationship between humble leadership and employee creative performance. Traditionality strengthens the mediation process when traditionality is high.

These findings provide several theoretical and practical implications for the domains of humble leadership and boundary spanning behavior. For example, human resource (HR) departments can recruit leaders with high humility and cultivate team leaders through systematic training programs about self-awareness, openness and self-transcendence; team leaders should encourage employees to participate in boundary spanning activities and hiring managers select employees with high traditionality to synergize with leader humility.

Based on the SET, this paper explored the behavioral mechanism between humble leadership and creative performance and enriched the prior research, which is from the cognitive or emotional view, and further answered the question “what are the employees' behavioral responses when they confront the humble leadership”.

Previous studies have reached inconsistent conclusions on foreign direct investment (FDI) technology spillovers and corporate innovation. The main purpose of this paper is to explore the technological spillover effects of FDI from the microperspective of firm linkages induced by geographic distance. Further analysis is conducted on the impact and mechanism of this spillover on the innovation quality of Chinese enterprises. The conclusions drawn from this paper can guide Chinese enterprises' foreign capital utilization and innovation strategy choices.

Using the data of China's A-share listed companies from 2009 to 2019, this paper explores the role of FDI technology spillover in enterprise innovation quality through a two-way fixed-effect model. The robustness of the results is proven by substituting variables, adding industry fixed effects and excluding high-profit groups, and further using the two-stage least squares (2SLS) method to alleviate the empirical endogeneity problem.

These findings indicate that FDI technology spillover based on geographic proximity has a positive impact on the innovation quality of Chinese enterprises. However, there are different impacts for different types of enterprises. FDI technology spillover has a positive impact on the innovation quality of non-state-owned enterprises (non-SOEs) and small- and medium-sized enterprises (SMEs), while it has no effect on state-owned enterprises (SOEs) and large enterprises. The authors also find that the degree of financing constraints and R&D investment are important transmission mechanisms between FDI technology spillover and enterprise innovation quality.

This study ignores industry characteristics when considering foreign enterprises around Chinese enterprises. In fact, technology spillover effects differ across industries. When the authors matched microdata to regions, only the provincial level was considered. Therefore, there is still room for further research. In future research, the authors should consider industry characteristics and group foreign enterprises and Chinese enterprises in the same industry and in different industries to explore industry differences in technology spillover. In addition, when matching corporate data to regions, the authors can match to the city level and draw city-level conclusions.

This study is different from previous studies that focus on the quantity of enterprise innovation or innovation output. The authors focus on the role of technological spillovers in the quality of Chinese enterprise innovation, enriching research in the field of enterprise innovation quality. In addition, the current FDI technology spillover indicators are technically difficult to measure at the micro level. The authors draw inspiration from the theory of the geographical structure of financial supply and combine the creation methods of macro and micro indicators in existing articles in other fields. The authors ingeniously construct a new FDI technical spillover indicator. This indicator combines the commonly used regional FDI technology spillover with the geographic proximity of enterprises at the microlevel by constructing an interaction term between the two. This indicator not only alleviates the endogeneity problem to a certain extent but also has implications for future research in the field of FDI technology spillovers at the micro level.

(1) FDI technology spillovers are an effective way to improve the innovation quality of local enterprises, especially for non-SOEs and SMEs. Therefore, The authors suggest that in the context of dual circulation, the Chinese government should continue to open wider to the outside world and encourage foreign enterprises to invest in China. (2) In future development, managers of SOEs and large enterprises should create an innovation incentive mechanism. Moreover, they should change their vertical management structure and make full use of their policy advantages and budget advantages to increase innovation activities. In the process of acquiring technology spillovers, enterprises need to solve their own financing constraints.

First, this study solves a technical problem. It is technically difficult to measure the current FDI technical spillover indicators at the micro level. This study innovatively constructs a new FDI technology spillover indicator that combines regional FDI technology spillovers with the microperspective of the geographical proximity of enterprises. This approach not only alleviates certain endogeneity problems in the empirical evidence but also enriches relevant research in the field of technology spillover. In addition, this study focuses on the impact and mechanism of this spillover, which addresses the current research gap among previous studies that mainly focus on innovation quantity and ignore innovation quality.

This paper aims to study the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass.

The authors performed weight loss experiments, electrochemical experiments including the polarization curve and electrochemical impedance spectrum, corrosion morphology observation using scanning electron microscope (SEM) and atomic force microscope (AFM) and surface composition analysis via X-ray photoelectron spectroscopy (XPS) to analyze the corrosion inhibition behavior of imidazopyridine and its three derivatives on brass by using quantum chemical calculation (Gaussian 09), molecular dynamics simulation (M-S) and Langmuir adsorption isotherm.

According to the results, imidazole-pyridine and its derivatives were found to be modest or moderately mixed corrosion inhibitors; moreover, they were spontaneously adsorbed on the metal surface in a single-layer, mixed adsorption mode.

The corrosion inhibition properties of pyrazolo-[1,2-a]pyridine and its derivatives on brass in sulfuric acid solution were analyzed through weight loss and electrochemical experiments. Moreover, SEM and AFM were simultaneously used to observe the corrosion appearance. Furthermore, XPS was used to analyze the surface. Then, Gaussian 09 and M-S were combined along with the Langmuir adsorption isotherm to investigate the corrosion inhibition mechanism of imidazole-[1,2-a]pyridine and its derivatives.

The study aims to understand the relationship between facilitating, demoting, motivating factors and visit intention; and to clarify the role of death anxiety before visiting a dark exhibition.

Partial least squares structural equation modeling was adopted to analyze data from 426 potential visitors to the Capuchin Crypt in Rome (Italy).

Results demonstrate that dark fascination, prestige, reflection on death and mortality and interpersonal facilitators are the main drivers of visit intention, and structural constraints are the main demoting factors. Contrary to expectations, intrapersonal constraints have a positive influence on motivators and indirectly on visit intention, and death anxiety has mixed results.

Data collection from only one dark exhibition requires that the generalization of the results must be done with care.

Conclusions enabled a better understanding of pre-trip tourist behavior, providing valuable suggestions for the communication strategy of Destination Management Organizations (DMOs) and site managers.

The study adopts a consolidated and empirical approach to studying facilitators, motivators, constraints and visit intention, as well as the effect of death anxiety. To the best of the author’s knowledge, this is the first study to develop a comprehensive investigation of these four constructs, whether at the darker or the lighter end of the dark tourism spectrum. Consequently, it offers a better understanding of lighter dark attractions, which allows DMOs and others to improve the communication of their tourism products.

This study investigates the way in which acquisition-related human factors affect knowledge transfer in the context of Chinese cross-border M&A for strategic assets. The authors find that the process of knowledge transfer is reciprocal for revenue and cost synergies, including explicit and tacit knowledge. The establishment of joint ventures (JV) in China after the takeover boosts product-oriented knowledge transfer from overseas-acquired firms in mature markets to Chinese acquirers. The promotion of overseas synergies stimulates complementary knowledge transfer flow, which is reversely transferred from Chinese acquirers to overseas-acquired subsidiaries such as low-saving sourcing and new market applications. This study identifies three acquisition-related human factors that impact overseas knowledge senders for knowledge transfer. These human factors are implemented by Chinese strategic investors as new shareholders during the loosen integration phase. The first facilitator is all-round communication programs with top management involvement, aiming to build up constructive communication channels to boost knowledge transfer. The second facilitator is competence-based trust, which stimulates cooperation and application based on similar professional competence between Chinese acquirers and their overseas-acquired subsidiaries. The impeder is a high turnover of key skilled workers at Chinese acquirers to undermine the effectiveness of knowledge transfer.

Purpose: Blockchain technology has exploded in popularity in the social economy over the years. Because blockchain technology offers so many advantages, it was first employed for Bitcoin transactions. The interaction between blockchain technology and financial industries will grow more personal and interwoven with the introduction of Bitcoin. As the value of blockchain technology became evident, more financial companies began to test its use in monetary operations. Numerous financial companies have been experimenting with blockchain technology to reduce the transactional costs and to improve the efficiency of operations, specifically in the domain of financial notes, cross-border payments, and asset-backed securitisation. Blockchain will have a broad range of applications in the financial industry shortly.

Methodology: Through financial tools and methods, trust may result in successful businesses. In the long term, blockchain technology is generally a significant source of the finance industry revolution. It allows you to create immutable transaction histories available to everyone on the network. A blockchain system consists of a sequence of blocks connected by a connection to the block before each block. Each block comprises more than one transaction representing changes in the ownership of assets on the ledger. A consensus procedure is employed to add new blocks to the existing chain, in which members of the public blockchain confirm that transactions are accurate.

Findings: Blockchain technology is still in its infancy. The challenges of sustainability, privacy, secrecy, and latency, among others, have surfaced. Financial markets must get a deeper grasp of Blockchain to provide trustworthy alternatives.

Significance: The book chapter highlights the architecture, protocols, and applications of Blockchain Technology. The chapter will also enlighten the readers about the challenges and solutions of Blockchain Technology in the Financial Market. Moreover, the chapter also discusses the future research scope of Blockchain Technology in the Financial Market.

This study aims to investigate the two-dimensional magnetohydrodynamic flow and heat transfer of a fractional Maxwell nanofluid between inclined cylinders with variable thickness. Considering the cylindrical coordinate system, the constitutive relation of the fractional viscoelastic fluid and the fractional dual-phase-lag (DPL) heat conduction model, the boundary layer governing equations are first formulated and derived.

The newly developed finite difference scheme combined with the L1 algorithm is used to numerically solve nonlinear fractional differential equations. Furthermore, the effectiveness of the algorithm is verified by a numerical example.

Based on numerical analysis, the effects of parameters on velocity and temperature are revealed. Specifically, the velocity decreases with the increase of the fractional derivative parameter α owing to memory characteristics. The temperature increase with the increase of fractional derivative parameter ß due to a decrease in thermal resistance. From a physical perspective, the phase lag of the heat flux vector and temperature gradients τ_q and τ_T exhibit opposite trends to the temperature. The ratio τ_T/τ_q plays an important role in controlling different heat conduction behaviors. Increasing the inclination angle θ, the types and volume fractions of nanoparticles Φ can increase velocity and temperature, respectively.

Fractional Maxwell nanofluid flows from a fixed-thickness pipe to an inclined variable-thickness pipe, and the fractional DPL heat conduction model based on materials is considered, which provides a basis for the safe and efficient transportation of high-viscosity and condensable fluids in industrial production.