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This study aims to review the recent advancements in high entropy alloys (HEAs) called high entropy materials, including high entropy superalloys which are current potential alternatives to nickel superalloys for gas turbine applications. Understandings of the laser surface modification techniques of the HEA are discussed whilst future recommendations and remedies to manufacturing challenges via laser are outlined.

Materials used for high-pressure gas turbine engine applications must be able to withstand severe environmentally induced degradation, mechanical, thermal loads and general extreme conditions caused by hot corrosive gases, high-temperature oxidation and stress. Over the years, Nickel-based superalloys with elevated temperature rupture and creep resistance, excellent lifetime expectancy and solution strengthening L12 and γ´ precipitate used for turbine engine applications. However, the superalloy’s density, low creep strength, poor thermal conductivity, difficulty in machining and low fatigue resistance demands the innovation of new advanced materials.

HEAs is one of the most frequently investigated advanced materials, attributed to their configurational complexity and properties reported to exceed conventional materials. Thus, owing to their characteristic feature of the high entropy effect, several other materials have emerged to become potential solutions for several functional and structural applications in the aerospace industry. In a previous study, research contributions show that defects are associated with conventional manufacturing processes of HEAs; therefore, this study investigates new advances in the laser-based manufacturing and surface modification techniques of HEA.

The AlxCoCrCuFeNi HEA system, particularly the Al0.5CoCrCuFeNi HEA has been extensively studied, attributed to its mechanical and physical properties exceeding that of pure metals for aerospace turbine engine applications and the advances in the fabrication and surface modification processes of the alloy was outlined to show the latest developments focusing only on laser-based manufacturing processing due to its many advantages.

It is evident that high entropy materials are a potential innovative alternative to conventional superalloys for turbine engine applications via laser additive manufacturing.

The purpose of this paper is to design a unified operational design domain (ODD) monitoring framework for mitigating Safety of the Intended Functionality (SOTIF) risks triggered by vehicles exceeding ODD boundaries in complex traffic scenarios.

A unified model of ODD monitoring is constructed, which consists of three modules: weather condition monitoring for unusual weather conditions, such as rain, snow and fog; vehicle behavior monitoring for abnormal vehicle behavior, such as traffic rule violations; and road condition monitoring for abnormal road conditions, such as road defects, unexpected obstacles and slippery roads. Additionally, the applications of the proposed unified ODD monitoring framework are demonstrated. The practicability and effectiveness of the proposed unified ODD monitoring framework for mitigating SOTIF risk are verified in the applications.

First, the application of weather condition monitoring demonstrates that the autonomous vehicle can make a safe decision based on the performance degradation of Lidar on rainy days using the proposed monitoring framework. Second, the application of vehicle behavior monitoring demonstrates that the autonomous vehicle can properly adhere to traffic rules using the proposed monitoring framework. Third, the application of road condition monitoring demonstrates that the proposed unified ODD monitoring framework enables the ego vehicle to successfully monitor and avoid road defects.

The value of this paper is that the proposed unified ODD monitoring framework establishes a new foundation for monitoring and mitigating SOTIF risks in complex traffic environments.

Container terminal operation is one of the most risky industries. Many of the accidents that occurred were found to be caused by human errors. However, it seems relatively little research has been conducted to examine the influence of leader-member exchange (LMX) relationship on employee safety behavior. Therefore, the purpose of this study is to examine the effects of leader-member exchange and safety climate on employees’ safety organizational citizenship behaviors (SOCB) in the container terminal context based on the social exchange theory.

A structural equation modeling was used with confirmatory factor analysis, and survey data are collected from 265 employees in major container terminals in Taiwan.

Results indicated that LMX is positively associated with safety climate, whereas safety climate positively influences employees’ safety citizenship behavior. Specifically, results indicated that safety climate mediates the effect of LMX on employees’ SOCB.

This study was limited to LMX dimensions adapted from the studies of Li and Liao (2014) and Vidyarthiv et al. (2014). Future research could examine the linkages between LMX, ethical climate, safety performance and supervisor leadership influence. Furthermore, this research focused specifically on employees from the container terminal operators in Taiwan. It would be valuable to collect data from employees from other countries to obtain a balanced view of the relationship between LMX, team-member exchange (TMX), safety climate and employee SOCB in container terminal operations.

This research provides a useful implication for container terminal operators to enhance LMX qualities and employee safety behavior through organizational participation, employee-helping behaviors and informing workers to obey safety rule and regulation.

Given the prevalence of accidents and unsafe behavior in container terminal operations, this research sought to examine the relationships among LMX, safety climate and employee SOCB in the container terminal context. Theoretically, this study highlights the importance of LMX and safety climate in explaining the SOCB of employees.