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This paper aims to identify the optimal forming angle for the selective laser melting (SLM) process and evaluate the mechanical properties of the SLM-formed GH3536 alloy in the aero-engine field.

Forming the samples with optimized parameters and analyzing the microstructure and properties of the block samples in different forming angles with scanning electron microscope, XRD, etc. so as to analyze and reveal the laws and mechanism of the block samples in different forming angles by SLM.

There are few cracks on the construction surface of SLM formed samples, and the microstructure shows columnar subgrains and cellular subgrains. The segregation of metal elements was not observed in the microstructure. The pattern shows strong texture strength on the (111) crystal plane. In the sample, the tensile strength of 60° sample is the highest, the plasticity of 90° forming sample is the best, the comprehensive property of 45° sample is the best and the fracture mode is plastic fracture. The comprehensive performance of the part is the best under the forming angle of 45°. To ensure the part size, performance and support structure processing, additional dimensions are added to the part structure.

In this paper, how to make samples with different forming angles is described. Combined with the standard of forged GH3536 alloy, the microstructure and properties of the samples are analyzed, and the optimal forming angle is obtained.

Metal green parts fabricated by indirect selective laser sintering (SLS) have lower mechanical properties, and thus, they cannot satisfy practical application. To enhance their performance, two polymer resins were compounded as a modified material to infiltrate into the metal parts by SLS.

The viscosity and glass-transition temperature were tested by a viscometer and differential scanning calorimetry, respectively. The microstructure and morphology of the interface of parts by polymer resin infiltrated were observed to be using scanning electron microscopy. The tensile strength of sample parts was tested, too. The temperature tolerances of two mass ratio polymer materials were tested and compared by thermo-gravimetric analysis (TGA).

Compared to those without being polymer material infiltrated, the results of test showed that the tensile strength of the metallic parts is enhanced obviously, about four times. In addition, the analysis of TGA showed that the resin of mass ratio of 2:1 can be endured up to 200° and can be used as infiltrating materials for metal parts.

Therefore, plastic injection mold and function part can be manufactured by this method.

The purpose of this paper is to investigate the thermal fatigue behavior of a single Sn-3.0Ag-0.5Cu (SAC) lead-free and 63Sn-37Pb (SnPb) solder joint treated by rapidly alternating heating and cooling cycles.

With the application of electromagnetic-induced heating, the specimen was heated and cooled, controlled with a system that uses a fuzzy logic algorithm. The microstructure and morphology of the interface between the solder ball and Cu substrate was observed using scanning electron microscopy. The intermetallic compounds and the solder bump surface were analyzed by energy-dispersive X-ray spectroscopy and X-ray diffraction, respectively.

The experimental results showed that rapid thermal cycling had an evident influence on the surface and interfacial microstructure of a single solder joint. The experiment revealed that microcracks originate and propagate on the superficial oxide of the solder bump after rapid thermal cycling.

Analysis, based on finite element modeling and metal thermal fatigue mechanism, determined that the rimous cracks can be explained by the heat deformation theory and the function of temperature distribution in materials physics.

With the rapid development of social media in the past few years, some dark aspects of usage have appeared, e.g., Weibo addiction. Therefore, the purpose of this paper is to address the question of how Weibo keeps users hooked.

The study utilizes the netnography method to explore the symptoms of Weibo addiction and how it is formed.

First, some Weibo users have typical symptoms of addictive behavior, such as withdrawal, loss of control and general living problems; second, narcissism plays an important role in the process of Weibo addiction and has a stronger effect on content generation than content consumption; third, some users use Weibo as a means to alleviate anxiety, but they can then become more anxious owing to addiction; and fourth, the effect of comments has two sides – on the one hand, comments are one kind of feedback to posts, satisfying posters’ social needs, while on the other hand, a storytelling system consists of one post and its comments, upon which some Weibo users become more dependent.

This research is only a preliminary, exploratory study. Therefore, care should be taken when interpreting these findings.

This study should help social media service providers and users to pay attention to the risk of social media addiction. Social media service providers should take social responsibility, design more user-oriented guidelines for marketing ethics and launch more responsible marketing activities. Users should enhance self-control and better balance social media use and offline real life.

Netnography has not been widely used as an addictive behavior research technique. This study is further bolstered because it has also noticed the difference of addiction mechanisms between addictive micro-bloggers and their followers.

This chapter focuses on visualization. Seeing the humanities differently is one of the amazing benefits of working with tools mentioned within this category. Whether it be more traditional visualizations like images or video or that which is considered a bit more advanced like augmented or virtual reality, the enhanced perspective gained through the use of these tools offers digital humanities scholars unprecedented disciplinary perspectives while helping to shape new research areas, questions, and understanding of humanity and culture. In addition to visualization and issues related to it, this chapter also examines gaming and how games and play are impacting the digital humanities in exciting ways.

This study aims to examine the impact of perceived risk dimensions, confirmation, perceived usefulness and perceived ease of use on user satisfaction and their continuance intention to use mobile payments across Vietnam based on the extended technology continuance theory (TCT).

This study used an online questionnaire-based survey design to collect data from 417 respondents using judgmental and snowball sampling techniques. The respondents in this survey are personal users of mobile payments across Vietnam. Data analyses and hypothesis testing were carried out using the partial least squares structural equation modeling.

The findings demonstrate that physical risk, time loss risk, opportunity cost risk, confirmation, perceived ease of use and perceived usefulness are important elements influencing consumers’ satisfaction toward continuance intentions to use mobile payment services. Satisfaction is also significantly associated with continuance intentions to use mobile payments across Vietnam. Other relationships, including functional risk, social risk, financial risk and information risk are not significantly related to satisfaction. These results are expected to be useful for mobile payment service providers. Understanding the factors mentioned in this study enables mobile payment service providers to improve their offerings strategically and then motivate their clients to keep using mobile payments.

The work is among the very few bodies of empirical research to investigate the continuance intention to use mobile payments using the extended TCT by incorporating the various dimensions of perceived risk construct in the fintech sector to develop a research model for this study. Furthermore, combining with perceived risk dimensions, this study expands the TCT model’s mobile app to the fintech sector, and advances the understanding of the use of the extended TCT in the fintech sector and adds to the theory.

The purpose of this qualitative study was to determine international students’ satisfaction on the quality of a private university in Turkey and the factors which influence their satisfaction. The study also investigated international students’ suggestions to improve their studies and life in Turkey. For these purposes, focus group interviews were conducted with 27 international students. Deductive coding was used to analyse collected data. The findings show that international students’ satisfaction is shaped by a number of different factors including, perceived quality of teaching, living and support service experiences and scholarships. Results also showed that participants considered extracurricular activities as an important part of their experiences when it comes to improving their campus life and learning experience.

The purpose of this study is to understand the determinants affecting behavioral intention (BI) to use ePharmacy services. The moderating role of technology discomfort in the relationship between BI and the actual use of ePharmacies in the context of Bangladesh is also examined.

A descriptive, quantitative approach was used to consider the UTAUT-2 model. Using the convenience sampling method, 255 responses were collected. The data were analyzed using Smart-PLS 3.2 software to investigate the hypothesized relationships.

The findings reveal that website information, doctors’ services, performance expectancy, return policy, social influence, perceived reliability and facilitating conditions are significantly related to the BI to use ePharmacy services. Interestingly, the structural equation modeling results also confirmed that technology discomfort has no moderating effect on the relationship between BI and actual usage behavior.

This research provides theoretical contribution by extending the practical knowledge focusing on the relationship of ePharmacy, BI and actual usage behavior by using UTAUT-2 model – a relevant and unexplored issue in the easting literature, offering several research opportunities as the future avenue.

The result highlights the economic and social relevance from the perspective of a developing country. As people are showing their intention toward ePharmacy, managers and decision-makers need to take strategic decision to overcome any difficulties. Policymakers need to improve their services for the expansion of ePharmacy through different development projects.

This study advances past studies on the use of ecommerce in the pharmaceutical industry and provides a general understanding of customers in developing countries.

This study aims to find out the influence of green practices used by the five-star hotels on the guest’s online hotel assessment and their revisit intentions. It also evaluated how the use of green practices by the hotels influenced the guest’s willingness to pay a premium price. Apart from the conventional hotel service attributes, this study also identified some new and innovative services offered by the hotels which have an overall effect on the guest’s revisit intentions.

This study applied focus group interviews from 12 hotel managers and accessed the hotel’s internal database to identify the latest and innovative service attributes offered by the hotels. The information regarding the green practices offered by the hotels was collected through TripAdvisor and LEED-IGBC website. It identified 10 independent and four dependent variables based on previous literature. Guest’s revisit intentions were measured on a five-point Likert scale. Data was analysed using a multi-step hierarchical regression model.

The use of green practices by the hotels revealed a positive and significant influence on the guest’s revisit-intentions and their intention to pay a premium price. It was also found that the use of new and innovative green practices has a positive influence on the guest’s overall online evaluation of the hotel.

This study suggests that the amalgamation of green practices along with the conventional service attributes may help in the incremental revisit and online hotel assessment intentions, which might be of use for the managers and hotel policymakers.

Although previous studies have explored the conventional hotel service attributes in the context of Indian Hotel industry, this is one of the first studies which discussed the influence of recent and emerging hotel service attributes on the guest’s revisit and pay a premium price intention. Moreover, the influence of green practices on the guest’s overall online evaluation of the five-star hotels in Delhi was discussed in this study which was not performed before.

The ability for learners to interact online via their avatars in a 3-D simulation space means that virtual worlds afford a host of educational opportunities not offered by other learning technology platforms, but their use also raises several pertinent issues that warrant consideration. This chapter reviews the educational use of virtual worlds from a design perspective. Virtual-world definitions are explored, along with their key educational characteristics. Different virtual-world environments are briefly contrasted, including Second Life, Active Worlds, Open Sim, and Minecraft. A wide variety of virtual-world uses in schools and universities are examined so as to understand their versatility. Key educational benefits of virtual worlds are distilled from the literature, such as the ability to facilitate 3-D simulations, role-plays, construction tasks, and immersive learning. Emergent issues surrounding the use of virtual worlds are also analyzed, including cognitive load, safety, and representational fidelity. One higher education and one school level vignette are provided in order to offer more detailed insight into the use of virtual worlds in practice. Recommendations for learning design and implementation are presented, based on the thematic analysis of contemporary virtual-worlds research.