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Discrete element method (DEM) has been extensively used in the laboratory of particulate and multiphase processing at the University of New South Wales (UNSW) to study the fundamentals of particulate matter at a particle scale. This paper briefly reviews the work in the laboratory, which covers the development of simulation techniques and their application to the study of particle packing and flow, transport properties and constitutive relationships of typical static or dynamic particulate systems. It is concluded, through representative comparison between simulated and measured results under different conditions, that DEM, as a major technique for discrete particle simulation, is an effective method for particle scale research of particulate matter.

The purpose of this paper is to make a numerical study of natural convection of water‐based nanofluids in a square cavity when a discrete heat source is embedded on the bottom wall, applying a “nanofluid‐oriented” model for the calculation of the effective thermal conductivity (Xu‐Yu‐Zou‐Xu's model) and the effective dynamic viscosity (Jang‐Lee‐Hwang‐Choi's model). Another motivation is the numerical solution of the equations of the flow with a meshless method.

A meshless point collocation method with moving least squares (MLS) approximation is used. A test validation study of the numerical method takes place for pure water flow, as well for water/Al₂O₃ nanofluids. The influence of pertinent parameters such as Rayleigh number (Ra), the non‐uniform nanoparticle size keeping the mean nanoparticle diameter fixed, the volume fraction of nanoparticles and the location of heat source on the cooling performance are studied.

The presence of a discrete heat source, as well as the various thermal boundary conditions affects the characteristics of the nanofluid flow and heat transfer. When the ratio of minimum to maximum nanoparticle diameter is increased, the local Nusselt number is increased and the heat source temperature is decreased. The increase of solid volume fraction of nanoparticles causes the heat source maximum temperature to decrease and the Nusselt Number to increase.

The present study constitutes an original contribution to the nanofluid flow and heat transfer characteristics when a discrete heat source is presence. “Nanofluid‐oriented” models are used for the calculation of the effective thermal conductivity and dynamic viscosity.

To effectively control the molten steel flow and the stability of free surface in continuous casting mould, this paper aims to propose a new type electromagnetic brake technique, namely, vertical electromagnetic brake (V-EMBr). Its brake effect under special processing parameters such as submerged entry nozzle (SEN) depth and port angle is evaluated by the numerical simulation methods.

A couple three-dimensional mathematical model of fluid flow and static magnetic field was developed to investigate the behaviour of molten steel flow and steel/slag interface in the continuous casting mould, and a volume of fluid model is used to track the interfacial behaviour of molten steel and liquid slag by solving the continuity equation of the phase volume fraction.

The simulation results showed that the application of V-EMBr can significantly reduce the flow intensity in upper recirculation zone and decrease the meniscus height and the flow velocity of molten steel in the vicinity of narrow side of mould, which is beneficial to reduce the possibility of mould flux entrapment. Especially, the brake effect of V-EMBr has a little affected by the SEN depth and port angle, which is helpful for V-EMBr to better adapt the actual continuous casting process.

Compared to the conventional-level EMBr, the new proposed V-EMBr has the advantage to effectively control the molten steel flow and steel/slag interfacial fluctuation in the vicinity of narrow side of mould with a pair of magnetic fields, and its brake effect is less affected by the changes in continuous casting processing parameters.

Friendships, an important form of people’s everyday relationships with others, have been studied by many scholars from different disciplines. However, there is limited research on friendship in the context of childhood, particularly that of Chinese rural children. This chapter presents findings from an in-depth study on Chinese children’s understandings and experiences of friendships with peers in the context of a rural primary boarding school. Data for this research were collected through an intensive five-month study, using an ethnographic approach, in a rural primary boarding school (given the pseudonym ‘Central Primary School’) in the western area of China in 2016. This chapter discusses parents’ influences on children’s selection of friends, particularly their ‘good’ friends, and their understandings of the functions of making friends in the context of rural China. It unpacks parents’ interventions on children’s friendships by discussing the moralised hierarchical relationship between children and their parents – children are expected to show obedience to parents. Then, it argues that the Confucian-collectivist values construct a relationship between a child’s individual achievement and their family’s collective good, which makes friendship not only an individual issue but also a collective one too.

Video game streaming (VGS) is emerging as an extremely popular, highly interactive, inordinately subscribed and very dynamic form of digital media. Incorporated environmental elements, gratifications and user pre-existing attitudes in VGS, this paper presents the development of an extended model of uses and gratification theory (EUGT) for predicting users' behavior in novel technological context.

The proposed model was empirically tested in VGS context due to its popularity, interactivity and relevance. Data collected from 308 VGS users and structural equation modeling (SEM) was employed to assess the hypotheses. Multi-model comparison technique was used to assess the explanatory power of EUGT.

The findings confirmed three significant types elements in determining VGS viewers' engagement, including gratifications (e.g. involvement), environmental cues (e.g. medium appeal) and user predispositions (e.g. pre-existing attitudes). The results revealed that emerging technologies provide potential opportunities for new motives and gratifications, and highlighted the significant of pre-existing attitudes as a mediator in the gratification-uses link.

This study is one of its kind in tackling the criticism on UGT of considering media users too rational or active. The study achieved this objective by considering environmental impacts on user behavior which is largely ignored in recent UGT studies. Also, by incorporating users pre-existing attitudes into UGT framework, this study conceptualized and empirically verified the higher explanatory power of EUGT through a novel multi-modal approach in VGS. Compared to other rival models, EUGS provides a more robust explanation of users' behavior. The findings contribute to the literature of UGT, VGS and users' engagement.

Available information for evaluating the possibility of hospitality firm failure in emerging countries is often deficient. Oversampling can compensate for this but can also yield mixed samples, which limit prediction models’ effectiveness. This research aims to provide a feasible approach to handle possible mixed information caused by oversampling.

This paper uses mixed sample modelling (MSM) when evaluating the possibility of firm failure on enlarged hospitality firms. The mixed sample is filtered out with a mixed sample index through control of the noisy parameter and outliner parameter and meta-models are used to build MSM models for hospitality firm failure prediction, with performances compared to traditional models.

The proposed models are helpful in predicting hospitality firm failure in the mixed information situation caused by oversampling, whereas MSM significantly improves the performance of traditional models. Meanwhile, only partial mixed hospitality samples matter in predicting firm failure in both rich- and poor-information situations.

This research is helpful for managers, investors, employees and customers to reduce their hospitality-related risk in the emerging Chinese market. The two-dimensional sample collection strategies, three-step prediction process and five MSM modelling principles are helpful for practice of hospitality firm failure prediction.

This research provides a means of processing mixed hospitality firm samples through the early definition and proposal of MSM, which addresses the ranking information within samples in deficient information environments and improves forecasting accuracy of traditional models. Moreover, it provides empirical evidence for the validation of sample selection and sample pairing strategy in evaluating the possibility of hospitality firm failure.

In an era where complex technological advances increasingly govern service delivery, it is incumbent on service firms to pioneer innovative strategies to sustain customer engagement and cultivate loyalty. This conceptual paper examines the transformative potential of artificial intelligence (AI) in the realm of online customer communities, with a particular focus on its creation, management and enhancement facets. The authors explore how AI can revolutionize the dynamics of customer interaction, feedback mechanisms and overall engagement within the service industry.

This conceptual paper draws from marketing and management literature focusing on customer communities and AI in service and customer engagement contexts with a robust future research agenda.

A classification of online customer community engagement is provided along with a conceptual framework to guide our understanding of the integration of AI into online customer communities.

This exploration underscores the imperative for service firms to embrace AI-driven approaches to online customer community management, not only as a means to optimize their operations but as a vital strategy to stay competitive in the ever-evolving digital landscape. This paper examines the novel combination of AI with online customer communities and provides the framework in the form of an input-process-output (IPO) model for future research into this integration.

The purpose of this paper is to discriminate fake interference caused by polygonal approximation so as to achieve accurate assembly sequence planning and assembly simulation.

An approximation zone model is proposed to formulate polygonal approximation. Fake interference is discriminated from hard interference by evaluating if polygonal models intersect within corresponding approximation zones. To reduce the computation, the surface-surface, surface-end face and end face-end face intersection test methods have been developed to evaluate the intersection and obtain collision data. An updated collision detection algorithm with this method is presented, which is implemented by a system named AutoAssem.

This method has been applied to a set of products such as a valve for assembly interference matrix generation, static and dynamic collision detection. The results show that it ensures the accuracy of assembly sequence planning and assembly simulation for polygonal models.

This method facilitates assembly design in the virtual environment with polygonal models. It can also be applied to computer aided design systems to achieve quick and accurate collision detection.

Fake interference between polygonal models may result in serious errors in assembly sequence planning and assembly simulation. Assembly zone model and novel polygon intersection verification methods have been proposed to effectively tackle this problem. Compared to current methods, this method considers valid penetration direction and approximation difference, does not need to process complicated auxiliary data and can be easily integrated with current collision detection methods.

Wellness tourism is growing in importance as increasing numbers of travelers place a priority on their health and well-being by traveling. This study examined the relationships between wellness tourism destination attributes, perceived quality, perceived mental health, eudaimonic well-being, overall satisfaction and behavioral loyalty to corroborate a model explaining wellness tourism destination loyalty in Thailand.

The conceptual model of this study was examined using a survey research design. The survey questionnaire was distributed to Chinese tourists who had previously traveled to Thailand and engaged in wellness tourism activities during their trip.

The findings revealed that healthful food choices, core facilities and staff service significantly influenced perceived quality. This perceived quality was a crucial factor in determining perceived mental health, which in turn impacted eudaimonic well-being. Overall satisfaction was directly influenced by perceived quality, perceived mental health and eudaimonic well-being. Additionally, perceived quality had a direct effect on behavioral loyalty.

With the growing global interest in wellness and travel, this study offers valuable insights for tourism marketers in Thailand to enhance their wellness tourism strategies. Tourism organizations should emphasize the quality of food, facilities and staff service to attract wellness-oriented travelers.

This study highlights the interconnectedness of perceived quality, good mental health and eudaimonic well-being. High-quality experiences contribute to improved mental health and in turn enhance eudaimonic well-being.