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This paper aims to understand the magnetohydrodynamics (MHD) mechanism in the molten pool under different modes of magnetic field. The comparison focuses on the Lorenz force excitation and its effect on the melt flow and solidification parameters, intending to obtain practical references for the design of magnetic field-assisted laser directed energy deposition (L-DED) equipment.

A three-dimensional transient multi-physical model, coupled with MHD and thermodynamic, was established. The dimension and microstructure of the molten pool under a 0T magnetic field was used as a benchmark for accuracy verification. The interaction between the melt flow and the Lorenz force is compared under a static magnetic field in the X-, Y- and Z-directions, and also an oscillating and alternating magnetic field.

The numerical results indicate that the chaotic fluctuation of melt flow trends to stable under the magnetostatic field, while a periodically oscillating melt flow could be obtained by applying a nonstatic magnetic field. The Y and Z directional applied magnetostatic field shows the effective damping effect, while the two nonstatic magnetic fields discussed in this paper have almost the same effect on melt flow. Since the heat transfer inside the molten pool is dominated by convection, the application of a magnetic field has a limited effect on the temperature gradient and solidification rate at the solidification interface due to the convection mode of melt flow is still Marangoni convection.

This work provided a deeper understanding of the interaction mechanism between the magnetic field and melt flow inside the molten pool, and provided practical references for magnetic field-assisted L-DED equipment design.

Carbon emission is one of the most important problems of today. In this framework, it is important for countries to take the necessary actions to solve this problem. Energy use is one of the most important causes of carbon emissions. Choosing fossil fuels in this process increases the carbon emission problem. Therefore, it is understood that countries should be more sensitive about energy types. In this context, renewable energy (RE) sources are recommended by experts. However, due to some problems of these energy types, it does not seem possible to meet all energy needs from these sources. It is thought that nuclear energy will produce a permanent solution to the carbon emission problem. In this context, it is recommended that the use of nuclear energy be put on the agenda by countries.

Der Verstorbene darf als einer der Pioniere der Fremdenverkehrswissenschaft angesprochen werden. Seine Aufenthalte in Java und Japan, seine vielen Auslandreisen und seine Tätigkeit im wichtigen Fremdenverkehrszentrum Amsterdam verschafften ihm eine umfassende Kenntnis des nationalen und internationalen Tourismus. Als erfolgreicher Kaufmann und Ingenieur besass er zudem einen klaren Blick für die wesentlichen Zusammenhänge. Seine technisch‐mathematische Begabung und Ausbildung befähigten ihn dazu, diese präzis darzustellen. Damit erkannte er schon früh die Notwendigkeit, den Fremdenverkehr wissenschaftlich zu untersuchen und zu erfassen.

The Chinese civilization is an important part of the history of mankind. The purpose of this paper is to show that there are project management lessons to be learned from Chinese history, including that relating to the management of the building process in ancient China.

Through a review of the literature, this paper discusses the key management and economic practices in the building process of ancient China and highlights these practices from an important document, the Yingzao Fashi or (“Treatise on Architectural Methods”), that was compared with the modern‐day project management framework.

This paper explains the official systems instituted for public projects; the management of labour, design and planning of construction works; quantity surveying practices; the use, control and recycling of building materials; and inspection of building elements in ancient China.

The study suggests that lessons in the principles of construction project management in ancient China bear many similarities with the nine areas of modern‐day project management body of knowledge relating to integration, scope, time, cost, quality, human resource, communications, risk, and procurement management. An area for future research would be to compare the Yingzao Fashi with modern‐day codes of practice for building works to determine which of its “ancient” provisions relating to quality management are still relevant today.

It was found that much emphasis was placed by the ancient Chinese on the quality aspects of prominent building projects. This is one facet from which modern‐day project managers and clients can draw lessons.

The paper aimed to explore the underlying work engagement role in transformational leadership and employees' job performance relationships. Moreover, this study also looked at the moderation of leaders' managerial skills in the transformational leadership and work engagement nexus.

The time-lagged data of 360 followers — leader dyads nested in 71 teams were collected from star-rated hotels in Italy and structural equation modeling (SEM) analysis was executed.

Based on social learning theory and idiosyncrasy credit theory, the SEM results demonstrate that transformational leadership is significantly and positively linked with job performance and work engagement mediated this relationship. The results also confirmed that leaders' managerial skills strengthen the transformational leadership and work engagement nexus.

Hotel managers should consider hiring individuals with transformational leadership skills and provide training to Polish their managerial skills in order to enhance employee engagement at work, which may result in job performance.

With this study, the researchers emphasize the significance of transformational leadership and work engagement for better job performance in the Italian hospitality industry. Our analysis also provides new evidence that leaders' managerial skills strengthen the transformative leadership and work engagement nexus. The study is one of the first to investigate the boundary conditions of leaders' managerial skills in the transformational leadership and work engagement relationship. Based on the findings, the practical and theoretical contributions are also discussed.

Tourist regions have to adapt their offer to the continuously changing needs (new holiday trends, generation changes of travelers), in order to protect their markets. This especially holds for the fields of culture, entertainment and gastronomy.