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The purpose of this study is to design and develop a new functional coating system for aerospace AL7075-T6 alloy that would evaluate the mechanical properties of the coating.

This paper outlines the scratch adhesion characterisation of Cr/CrAlN coating using a combination of radio frequency (RF) and direct current (DC) physical vapour deposition (PVD) magnetron sputtering. The surface morphology, microstructure and chemical composition of the Cr/CrAlN film were evaluated by optical microscopy (OM), field emission scanning electron microscopy (FESEM) integrated with energy-dispersive X-Ray spectroscopy (EDX) and atomic force microscopy (AFM). The film-to-substrate adhesion was measured by a scratch test machine manufactured with a detection system, motorized stages, penetration depth sensors, optical microscope and tangential frictional load sensors.

The AFM and ultra-micro hardness results showed an increase in surface roughness to about 20 per cent and hardness to about 74 per cent. Moreover, the film-to-substrate adhesion strength of 1,814 mN was obtained with PVD deposition process.

The main limitation of this work is caused by PVD deposition process. Besides, surface defects such as pinholes contribute to a decrease in adhesion strength.

The higher hardness of CrAlN coating is used to improve the properties of softer aluminium substrates. This hardness prevents ploughing-induced wear and provides greater adhesion strength by preventing coating delamination.

Until now, CrAlN is coated only on ferrous alloys. It has not yet been tried on aluminium alloys. Moreover, coating functionality depends on higher adhesion and failure mechanisms involved in the film-to-substrate system, which is significant in aerospace applications.

Preparing CrAlN coatings on the surface of silicon nitride bearings can improve their service life in oil-free lubrication. This paper aims to match the optimal process parameters for preparing CrAlN coatings on silicon nitride surfaces, and reveal the microscopic mechanism of process parameter influence on coating wear resistance.

This study used molecular dynamics to analyze how process parameters affected the nucleation density, micromorphology, densification and internal stress of CrAlN coatings. An orthogonal test method was used to examine how deposition time, substrate temperature, nitrogen-argon flow rate and sputtering power impacted the wear resistance of CrAlN coatings under dry friction conditions.

Nucleation density, micromorphology, densification and internal stress have a significant influence on the surface morphology and wear resistance of CrAlN coatings. The process parameters for better wear resistance of the CrAlN coatings were at a deposition time of 120 min, a substrate temperature of 573 K, a nitrogen-argon flow rate of 1:1 and a sputtering power of 160 W.

Simulation analysis and experimental results of this paper can provide data to assist in setting process parameters for applying CrAlN coatings to silicon nitride bearings.

The purpose of this study is to investigate the effect of catalyst distribution in the combustion catalytic layer on heat and mass transport characteristics of the auto-thermal methanol steam reforming microchannel reactor.

Computational fluid dynamics (CFD) method is used to study four different gradient designs. The corresponding distributions of temperature, species and chemical reaction rate are provided and compared.

The distributions of species, temperature and chemical reaction rate are significantly affected by the catalyst distribution in the combustion catalytic layer. A more uniform temperature distribution can be observed when the gradient design is used. Meanwhile, the methanol conversion rate is also improved.

This work reveals the effect of catalyst distribution in the combustion catalytic layer on heat and mass transport characteristics of the auto-thermal methanol steam reforming microchannel reactor and provides guidance for the design of reactors.

The temperature uniformity and hydrogen production performance can be improved by the gradient design in the combustion catalytic layer.

Incentive‐based executive compensation is regarded as a mechanism for alleviating agency problems between executives and shareholders. Seventy‐three New Zealand (NZ) listed companies are used to examine the relationship between executive incentive compensation schemes (ICS) and firm performance. The results suggest that neither compensation level nor adoption of an ICS are significantly related to returns to shareholders or ROA. However, there is a statistically significant relationship between Tobin's q and both CEO compensation and executive share ownership. Further, the evidence suggests the recent compensation disclosure requirements in NZ are not yet stringent enough to allow adequate analysis of the link between ICSs and corporate performance.

The purpose of this paper is to assess the feasibility of analytical models, specifically the radial basis function method, Akbari–Ganji method and Gaussian method, in conjunction with the finite element method. The aim is to examine the impact of processing parameters on temperature history.

Through analytical investigation and finite element simulation, this research examines the influence of processing parameters on temperature history. Simufact software with a thermomechanical approach was used for finite element simulation, while radial basis function, Akbari–Ganji and Gaussian methods were used for analytical modeling to solve the heat transfer differential equation.

The accuracy of both finite element and analytical methods was validated with about 90%. The findings revealed direct relationships between thermal conductivity (from 100 to 200), laser power (from 400 to 800 W), heat source depth (from 0.35 to 0.75) and power absorption coefficient (from 0.4 to 0.8). Increasing the values of these parameters led to higher temperature history. On the other hand, density (from 7,600 to 8,200), emission coefficient (from 0.5 to 0.7) and convective heat transfer (from 35 to 90) exhibited an inverse relationship with temperature history.

The application of analytical modeling, particularly the utilization of the Akbari–Ganji, radial basis functions and Gaussian methods, showcases an innovative approach to studying directed energy deposition. This analytical investigation offers an alternative to relying solely on experimental procedures, potentially saving time and resources in the optimization of DED processes.

Agency problems are more severe for multinational corporations (MNCs) and multinational enterprises compared to their domestic counterparts. As companies develop diversified operations, their managers face more challenges. An incentive compensation structure has been designed to align the benefits of managers with those of shareholders. Additionally, corporate social responsibility (CSR) has become increasingly crucial for companies. MNCs must gain the trust of more investors to improve their corporate reputation and financial performance. CSR enables MNCs with a high sense of social responsibility to expand their investor base, reduce perceived risks, and decrease information asymmetry. Our empirical findings reveal that Taiwanese MNCs can enhance their performance by implementing cash-based compensation and pursuing CSR activities.

The purpose of this paper is to study the effect of diode power detector modelling on six-port communication receiver performance.

Based on proposed and conventional squared diode model, six-port receiver’s demodulation and its error vector magnitude (EVM) performance due to hardware impairments are studied. Through considering both the models, the accuracy of proposed power detector model is compared to the squared model, and then both results are validated with envelope simulation (ENV) in advanced design system (ADS).

Comparing the numerical results with envelope simulation results proved that the proposed model is much more accurate than the conventional squared model for a wide range of input power levels.

Studying the receiver’s performance numerically, by considering the new proposed analytical approach for diode power detectors which is more accurate than the conventional squared model.

The purpose of this paper is to examine the performance implications of board size, composition and frequency of board meetings on the performance of banks.

The performance of banks is assessed on various parameters such as return on assets (ROA), Tobin’s Q, non-performing asset ratio (NPA ratio) and the net write-off ratio (NWO ratio). The effects of changes in board size and composition and frequency of meetings on the performance of banks are investigated using feasible generalized least square (FGLS) estimation of panel data covering a time span of five years concerning 40 banks incorporated in India. Frequency of board meetings is taken as a proxy for board activity and involvement. The authors have also tested for endogeneity issues in the model.

A curvilinear relationship was found between the board size and performance of banks. The authors have modelled a cubic form of the relationship for Indian banks. The authors’ findings indicate that an increase in board size is associated with better bank performance within both low and high board size ranges. Alternatively, increased board size is negatively associated with bank performance in the intermediate board size range. The study did not find any significant relationship between performance and frequency of board meetings and board composition.

The behavioural variables reflecting the involvement of the board have not been incorporated in the model to determine the impact of board involvement on the performance of banks owing to the availability of data. It is hoped that this paper will be useful for major regulatory bodies such as the Ministry of Corporate Affairs (MCA), Securities and Exchange Board of India (SEBI), Company Law Board (CLB) and stock exchanges in India and other emerging economies in devising listing norms and other governance-related aspects.

Non-linear relationships between the board size and performance are not normally prevalent in emerging economies, especially in the banking sector. However, such a relationship exists among the Indian banks. This paper is the first of its kind to identify and address the same.

Food waste occurs in every stage of the supply chain, but the value-added lost to waste is the highest when consumers waste food. The purpose of this paper is to understand the food waste behaviour of consumers to support policies for minimising food waste.

Using the theory of planned behaviour (TPB) as a theoretical lens, the authors design a questionnaire that incorporates contextual factors to explain food waste behaviour. The authors test two models: base (four constructs of TPB) and extended (four constructs of TPB plus six contextual factors). The authors build partial least squares structural equation models to test the hypotheses.

The data confirm significant relationships between food waste and contextual factors such as motives, financial attitudes, planning routines, food surplus, social relationships and Ramadan.

The data comes from an agriculturally resource-constrained country: Qatar.

Food waste originating from various causes means more food should flow through the supply chains to reach consumers’ homes. Contextual factors identified in this work increase the explanatory power of the base model by 75 per cent.

Changing eating habits during certain periods of the year and food surplus have a strong impact on food waste behaviour.

A country is considered to be food secure if it can provide its citizens with stable access to sufficient, safe and nutritious food. The findings and conclusions inform and impact upon the development of food waste and food security policies.

This paper aims to examine whether board-related characteristics matter for cost efficiency in banking sector.

This study uses a sample of publicly traded US commercial banks and savings institutions to estimate a relationship between cost efficiency measured by stochastic frontier analysis and a set of board-related characteristics for the period 2007-2013.

An inverted U-shape relation is found between board size and efficiency. Thus, there is a trade-off between costs and benefits of larger boards. Optimal board size is higher for banks with more complex operations. This study also observed an inverted U-shape relation between board independence and cost efficiency. The banks where the Chairman also executes the CEO responsibility show lower efficiency. However, a higher proportion of independent board members in banks with unitary leadership structure may mitigate the conflict of interest and lower efficiency stemming from CEO duality.

This study’s evidence supports the Basel Committee on Banking Supervision emphasis on advising a board composition that provides for a sufficient degree of director independence.

The results are relevant for banks and their external and internal stakeholders. Banks may adjust their current board characteristics to increase the board effectiveness. Externally, potential investors can evaluate the quality of corporate governance of banks before making investment decisions. The empirical findings can also be useful for regulators imposing corporate governance codes in banking.

To the best of the authors’ knowledge, this is the first paper to provide empirical evidence on the impact of board characteristics on bank efficiency for a wide panel of US banks. Additionally, a comprehensive set of board-related variables is used.