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The purpose of this paper is to make a numerical study of natural convection of water‐based nanofluids in a square cavity when a discrete heat source is embedded on the bottom wall, applying a “nanofluid‐oriented” model for the calculation of the effective thermal conductivity (Xu‐Yu‐Zou‐Xu's model) and the effective dynamic viscosity (Jang‐Lee‐Hwang‐Choi's model). Another motivation is the numerical solution of the equations of the flow with a meshless method.

A meshless point collocation method with moving least squares (MLS) approximation is used. A test validation study of the numerical method takes place for pure water flow, as well for water/Al₂O₃ nanofluids. The influence of pertinent parameters such as Rayleigh number (Ra), the non‐uniform nanoparticle size keeping the mean nanoparticle diameter fixed, the volume fraction of nanoparticles and the location of heat source on the cooling performance are studied.

The presence of a discrete heat source, as well as the various thermal boundary conditions affects the characteristics of the nanofluid flow and heat transfer. When the ratio of minimum to maximum nanoparticle diameter is increased, the local Nusselt number is increased and the heat source temperature is decreased. The increase of solid volume fraction of nanoparticles causes the heat source maximum temperature to decrease and the Nusselt Number to increase.

The present study constitutes an original contribution to the nanofluid flow and heat transfer characteristics when a discrete heat source is presence. “Nanofluid‐oriented” models are used for the calculation of the effective thermal conductivity and dynamic viscosity.

A high-fidelity simulation platform helps to verify the feasibility of the controller and reduce the cost of subsequent experiments. Therefore, this paper aims to design a high-fidelity hardware-in-the-loop (HIL) simulation platform for the tail-sitter vehicles.

The component breakdown approach is used to develop a more reliable model. Thruster dynamics and ground contact force are also modeled. Accurate aerodynamic coefficients are obtained through wind tunnel tests. This simulation system adopts a mode transition method to achieve continuous simulation for all flight modes.

Simulation results are in good agreement with the flight log and successfully predict the state of the vehicle.

First, the effects of the propeller slipstream are considered. Second, most researchers ignore the parasitic drag caused by the landing gear and other appendages, which is discussed in this study. Third, a ground contact model is implemented to allow a realistic simulation of the takeoff and landing phases. Fourth, complete wind tunnel tests are conducted to obtain more accurate aerodynamic coefficients. Finally, a mode transition method is deployed in the HIL simulation system to achieve continuous simulation for all flight modes.

This paper aims to design a global controller that is operational throughout all flight modes and less dependent on an accurate model.

By adopting the interconnection and damping assignment passivity-based control (IDA-PBC) technology and compensating extra inputs for handling the unknown dynamics and time-varying disturbances, a model-free control (MFC)-based global controller is proposed.

Test results indicate that the designed controllers are more suitable for actual flight as they have smaller position tracking errors and energy consumption in all flight phases than the excellent model-free controller intelligent-PID.

The designed global controller, which works in all flight modes without adjusting its structure and parameters, can realize a stable and accurate tracking control of a tail-sitter and improve the resistance to unknown disturbances and model uncertainties.

The newly-designed controller is considered as an enhanced version of the traditional MFC. It further improves the control effect by using the poorly known dynamics of the system and choosing the IDA-PBC as the control auxiliary input. This method eliminates the unnecessary dynamics to continuously stabilize the vehicle with suitable energy consumption covering its entire flight envelope.

This study aims to deal with the problem of trajectory tracking control for the quadrotor under external environmental disturbance and variable payloads.

In the field of unmanned aerial vehicle (UAV) control, external environmental disturbance and internal variable payloads as two major interference factors lead to control performance degradation or even instability, thus a trajectory tracking controller which innovatively combines sliding mode control technology and model-free control technique is proposed. The proposed controller is constructed with a learning rate-based sliding mode controller and an ultra-local model. Based on the proposed controller, the nonlinear system model of variable load quadrotor is locally estimated and the system’s uncertainties and disturbances can be compensated.

The simulation and actual test results demonstrate the satisfactory control performance and the robustness of the proposed controller compared with the PID and Backstepping controller under external environmental disturbance and variable payloads. Moreover, the proposed controller solves the trajectory tracking control problem not only when payloads change at the center of gravity but also when the position of load variation deviates from the center of gravity.

In both military and civilian domains, the quadrotor may encounter such situations that the payloads change, such as transporting goods, aerial refueling and so on. As a large internal interference factor, variable load tends to lead to unstable control. The research results provide theoretical guidance and technical support for trajectory tracking control of quadrotor under variable payloads.

The proposed controller combines learning rate-based sliding mode controller and model-free control technique to achieve a more efficient and accurate trajectory control of the quadrotor when considering system uncertainties and the load variation that happens in the unknown location.

A large, uneven settlement that is unfavourable to dam safety can occur between a concrete cut-off wall and the high-plasticity clay of earth core dam built on alluviums. This issue has been often studied using the small-strain finite element (FE) method in previous research. This paper aims to research the interaction behaviour between a concrete cut-off wall and high-plasticity clay using large-deformation FE analyses.

The re-meshing and interpolation technique with a small-strain (RITSS) method was performed using an independently developed program and adopted for large-deformation FE analyses, and a suitable element size for the high-plasticity clay region was suggested. The layered construction process of an earth core dam built on thick alluviums was simulated using the RITSS method incorporating a hyperbolic model for soil.

The RITSS method is an effective technique for simulating the soil–structure interaction during dam construction. The RITSS analysis predicted a higher maximum principle stress of the concrete cut-off wall and higher stress levels in the high-plasticity clay region than small-strain FE analysis.

A practical method for large-deformation FE analysis was advised and was used for the first time to study the interaction between a concrete cut-off wall and high-plasticity clay in dam engineering. Large deformation in the high-plasticity clay was handled using the RITSS method. Moreover, the penetration process of the concrete cut-off wall into the high-plasticity clay was captured using a favourable element shape and mesh density.

This chapter reviews developments concerning central bank digital currencies (CBDCs). It introduces, analyzes, and discusses the potential implications of CBDCs on the existing cryptoassets landscape. The chapter also provides an overview of the different approaches to adopting and implementing this new form of money. Additionally, it compares traditional cryptocurrencies, privately issued stablecoins, fiat currencies, and CBDCs. Although vastly divergent opinions exist on digital money’s purpose, benefits, and use cases, CBDCs can provide opportunities for innovation and experimentation at a central bank and systemic level. CBDCs may pave the way for democratizing access to unbundled financial services while rethinking the overall purpose of money, monetary systems, and global business.

ISO 14001 standard is the environmental certification developed by the International Organization for Standardization to describe the requirements for a certifiable Environmental Management System (EMS). The standard is included in the ISO 14000 series, developed because of the need for improved environmental quality. The current version of the ISO 14001 is the ISO 14001:2015; the purpose of the revision was to structure all the ISO standard (e.g., ISO9001) similarly and facilitate management systems’ integration.

The literature highlights that many drivers encourage companies to obtain the certification (e.g., need for an improved image of the company, pressure from customers, and ethical reasons), but there are also some barriers to its implementation (e.g., risk of spreading confidential information, reduction in productivity, and cost of the certification). However, the certification is connected to better performances indicated by the increase in process productivity and control, the reduction in resources’ consumption and waste, and the improved quality of products/processes.

This study aims to conduct a thorough literature review to map current studies on international marketing capabilities (IMCs) applying dynamic capabilities view (DCV). The aim of this study is to increase the chances for more conceptual and terminological rigor in future research in this particular research area.

This is a systematic literature review following the established review process of reviews in leading (international) marketing journals. A multilevel analytical approach was adopted, combining inductive coding with deductive coding and following the logic of antecedents-phenomena-consequences.

Synthesis of 20 rigorously selected previous empirical studies on IMCs applying DCV reveals that academic interest in these capabilities is well justified and growing and there are some well researched antecedents to focal capabilities (e.g. inter-organizational capabilities, outside-in market orientation) as well as their prevalent consequences (e.g. export and innovation performance). There is little knowledge of moderators to these links, especially with regard to consequences. This review illustrates that the current research lacks consistency in how key constructs are defined and measured, provides the guide to future conceptualization and measurement of so-called International Dynamic Marketing Capabilities (IDMCs) and proposes some concrete research directions.

The authors extend prior research in the investigated topic by critically evaluating prior works, providing improved conceptualization of IDMCs as well as concrete research agenda for IDMCs structured along recommendations for Theory, Context and Methods (TCM framework).

The purpose of this paper is to investigate whether CEO pay is related to stock price crash risk, and how ownership concentration mediates this relationship.

The authors hypothesize that companies who disclose CEO pay would experience lower stock price crash risk than their non-transparent peers. For companies whose CEO pay is published, the authors conjecture that the CEO pay slice is positively related to stock price crash risk. The authors also investigate whether the impact of CEO pay on crash risk would be weaker or stronger under a concentrated ownership structure and a mutual fund ownership structure. This study relies on 14,499 firm-year observations from the Chinese capital market to shed light on these questions.

The authors demonstrate that the magnitude of CEO pay slice has little effect on stock price crash risk. However, whether CEO pay is disclosed at all is a strong indicator for stock price crash risk.

The paper expands on the literature by adding a new factor to explain the stock price crash risk, which is vital to investor protection and the stability of the financial market. The research also adds to the sparse literature on CEO centrality and has implications for corporate governance and public policy.

This study aims to investigate how international entrepreneurial firms (IEFs) successfully commercialise innovative products/services internationally. In doing so, the authors examined the role played by the international dynamic marketing capability (IDMC) in the relationship between explorative and exploitative innovation and commercialisation. In addition, the authors also evaluated how the breadth and depth of international networks facilitate IEFs in upholding the effects of the IDMC to influence commercialisation.

To test the research model, structural equation modelling is used based on time-lagged survey data drawn from 201 Malaysian IEFs. To validate the results, additional robustness tests and endogeneity analyses have been performed.

The findings show that the IDMC positively mediates the relationship between explorative and exploitative innovation and commercialisation. Furthermore, the finding exhibits that the effects of the IDMC on commercialisation are positively moderated by the breadth and depth of international networks.

Given the fragmented and general nature of the extant marketing research on the IDMC, the study contributes to the international marketing literature by providing rich and nuanced pertinent knowledge. This study advances dynamic capability theory in relation to IEFs by establishing the IDMC as a functional capability suited to enable them to successfully commercialise the products/services resulting from explorative and exploitative innovation.