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The purpose of this study is to simulate the temperature distribution during an electron beam freeform fabrication (EBF³) process based on a fully threaded tree (FTT) technique in various scales and to analyze the temperature variation with time in different regions of the part.

This study presented a revised model for the temperature simulation in the EBF³ process. The FTT technique was then adopted as an adaptive grid strategy in the simulation. Based on the simulation results, an analysis regarding the temperature distribution of a circular deposit and substrate was performed.

The FTT technique was successfully adopted in the simulation of the temperature field during the EBF³ process. The temperature bands and oscillating temperature curves appeared in the deposit and substrate.

The FTT technique was introduced into the numerical simulation of an additive manufacturing process. The efficiency of the process was improved, and the FTT technique was convenient for the 3D simulations and multi-pass deposits.

This study aims to focus on the effect of interlayer bonding and thermal decomposition on the mechanical properties of fused filament fabrication-printed polylactic acid specimens at high extrusion temperatures.

A printing process, that is simultaneous manufacturing of contour and specimen, is used to improve the printing accuracy at high extrusion temperatures. The effects of the extrusion temperature on the mechanical properties of the interlayer and intra-layer are evaluated via tensile experiments. In addition, the microstructure evolution affected by the extrusion temperature is observed using scanning electron microscopy.

The results show that the extrusion temperature can effectively improve the interlayer bonding property; however, the mechanical properties of the specimen for extrusion temperatures higher than 270°C may worsen owing to the thermal decomposition of the polylactic acid (PLA) material. The optimum extrusion temperature of PLA material in the three-dimensional (3D) printing process is recommended to be 250–270°C.

A temperature-compensated constitutive model for 3D printed PLA material under different extrusion temperatures is proposed. The present work facilitates the prediction of the mechanical properties of specimens at an extrusion temperature for different printing temperatures and different layers.

This paper aims to focus on the accurate analysis of the fractional heat transfer in a two-dimensional (2D) rectangular monolayer tissue with three different kinds of lateral boundary conditions and the quantitative evaluation of the degree of thermal damage and burn depth.

A symplectic method is used to analytically solve the fractional heat transfer dual equation in the frequency domain (s-domain). Explicit expressions of the dual vector can be constructed by superposing the symplectic eigensolutions. The solution procedure is rigorously rational without any trial functions. And the accurate predictions of temperature and heat flux in the time domain (t-domain) are derived through numerical inverse Laplace transform.

Comparison study shows that the maximum relative error is less than 0.16%, which verifies the accuracy and effectiveness of the proposed method. The results indicate that the model and heat source parameters have a significant effect on temperature and thermal damage. The pulse duration (Δt) of the laser heat source can effectively control the time to reach the peak temperature and the peak slope of the thermal damage curve. The burn depth is closely correlated with exposure temperature and duration. And there exists the delayed effect of fractional order on burn depth.

A symplectic approach is presented for the thermal analysis of 2D fractional heat transfer. A unified time-fractional heat transfer model is proposed to describe the anomalous thermal behavior of biological tissue. New findings might provide guidance for temperature prediction and thermal damage assessment of biological tissues during hyperthermia.

Recently, sharing economy is gradually accepted by people, and it has expanded from life to knowledge. It is important to encourage people to produce high quality content in knowledge sharing area, and knowledge payment is one of the most effective ways to achieve it. Therefore, the knowledge payment has been regarded as a huge business opportunity, and it is of great meaning to study the development trend and feasibility of knowledge payment. This chapter, through big data methods, analyzes the business model of Zhihu (a Chinese platform of knowledge sharing) after it introduced knowledge payment projects, such as Zhihu Live and Pay Consultation. According to data of Zhihu users’ Q&A, concerned fields and others, this chapter tries to outline its user profile to find out the target groups of different topics, the proper form of knowledge payment and the hot topics of Zhihu Live. Through the analysis of knowledge graph, this chapter finds that Zhihu Live is expected to be the mainstream knowledge payment form in the future, and the most potential topics are mainly focused on science, law, and business. Meanwhile, it establishes a pricing model for Zhihu Live, and provides suggestions for the development of knowledge payment.

The purpose of this paper is to determine (1) the relationship between microstructure and fatigue cracking behavior and (2) effect of rolling on the process of crack initiation and propagation in FeCrAl alloys.

The qualitative and quantitative fracture studies were performed using scanning electron microscopy and the non-contact optical measurement system (IFMG5).

The results show that the formation of facets, rough facets and parallel stripes in the crack initiation and early crack propagation zones are closely related to the sensitivity of crack behavior to the microstructure of the material. Besides, the rolling process has a significant influence on the small crack initiation and propagation behavior. Quantitative analysis demonstrates that the size of the stress intensity factor and plastic zone size in the rough zone is associated with the rolling process.

The findings of this study have the potential to enhance the understanding of the microstructural crack formation mechanisms in FeCrAl alloys and shed light on the impact of rolling on the long-term and ultra-long fatigue behavior of these alloys. This new knowledge is vital for improving manufacturing processes and ensuring the safety and reliability of FeCrAl alloys used in nuclear industry applications.

This paper aims to focus on the research progress of intelligent self-healing anti-corrosion coatings in the aviation field in the past few years. The paper provides certain literature review supports and development direction suggestions for future research on intelligent self-healing coatings in aviation.

This mini-review uses a systematic literature review process to provide a comprehensive and up-to-date review of intelligent self-healing anti-corrosion coatings that have been researched and applied in the field of aviation in recent years. In total, 64 articles published in journals in this field in the last few years were analysed in this paper.

The authors conclude that the incorporation of multiple external stimulus-response mechanisms makes the coatings smarter in addition to their original self-healing corrosion protection function. In the future, further research is still needed in the research and development of new coating materials, the synergistic release of multiple self-healing mechanisms, coating preparation technology and corrosion monitoring technology.

To the best of the authors’ knowledge, this is one of the few systematic literature reviews on intelligent self-healing anti-corrosion coatings in aviation. The authors provide a comprehensive overview of the topical issues of such coatings and present their views and opinions by discussing the opportunities and challenges that self-healing coatings will face in future development.

This paper aims to analyze high-quality papers on the research of electronic word-of-mouth (eWOM) for product and service quality improvement from 2009 to 2022, in order to fully understand their historical progress, current situation and future development trend.

This paper adopts the bibliometrics method to analyze the relevant literature, including publishing trend and citation status, regional and discipline area distribution, and influential publications. Secondly, the VOSviewer is used for literature co-citation analysis and keyword co-occurrence analysis to obtain the basic literature and research hotspots in this research field.

Firstly, the study finds that the number of publications basically shows an increasing trend, and those publications are mainly published in tourism journals. In addition, among these papers, China has the largest number of publications, followed by the USA and South Korea. Through co-citation analysis of literature and keyword co-occurrence analysis, 22 foundational papers and six main research topics are obtained in this paper. Finally, this paper elaborates on the development trend of the research topic and future research directions in detail.

This is the first paper that uses bibliometrics to analyze and review relevant researches on eWOM for product and service quality improvement, which is helpful for researchers to quickly understand its development status and trend. This review also provides some future research directions and provides a reference for further research.

This study aims to answer few questions, such as which factors influence the local government’s choice of private firm investments; what factors influence private firms’ choice of specific local government to make a local investment; and why do some private firms gain a competitive edge by choosing a stakeholder management model of “running the government” in the context of the Chinese transition economy.

Using a case study approach, this paper provides an in-depth analysis of the Daqing–Geely Case, 2010, and explains why Geely chose Daqing considering the firm perspective and why the Daqing city Government chose Geely considering the local governments’ perspective.

This study highlights the concept of “co-beneficial” cooperation between government–business by virtue of the institutional innovation of the quasi-property system. In addition, it reveals that the private firms and local governments in the “Daqing–Geely mode” work together for mutual benefits by putting fair negotiation and contract mechanisms in place. Resultantly, private firms secure the commercial interests, and the local governments bring in improved efficiency.

This study consolidates the theory of stakeholders, thereby strengthening the current understanding of “special offer” and “universal offer.”

The investigations provide a basis for the optimization of the alloy 6061-T6 friction stir welding (FSW) process to improve the mechanical properties of welded joints.

The local deformation of the FSW joint in tension and fatigue test were experimentally investigated by digital image correlation (DIC) technique.

The local stress-strain behaviors of the sub-regions show that the plastic strain always concentrated at the heat affected zone (HAZ) on the advancing side both in tension and high cycle fatigue and eventually leads to the final fracture. The evolution of the plastic strain at very low stress is extremely slow and accounts for most of the total fatigue life. However, the local deformation exhibits a sudden increase just before the fatigue failure.

Based on the experimental data, the result indicates that the HAZ is the weakest zone across the weld and the strain localization in high cycle fatigue is very harmful and unpredictable for the FSW joints.