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This study aims to elucidate the machining properties of low-cost expanded clay-reinforced syntactic foams by using different neural network models for the first time in the literature. The main goal of this endeavor is to create a casting machining-neural network modeling flow-line for real-time foam manufacturing in the industry.

Samples were manufactured via an industry-based die-casting technology. For the slot milling tests performed with different cutting speeds, depth of cut and lubrication conditions, a 3-axis computer numerical control (CNC) machine was used and the force data were collected through a digital dynamometer. These signals were used as input parameters in neural network modelings.

Among the algorithms, the scaled-conjugated-gradient (SCG) methodology was the weakest average results, whereas the Levenberg–Marquard (LM) approach was highly successful in foreseeing the cutting forces. As for the input variables, an increase in the depth of cut entailed the cutting forces, and this circumstance was more obvious at the higher cutting speeds.

The effect of milling parameters on the cutting forces of low-cost clay-filled metallic syntactics was examined, and the correct detection of these impacts is considerably prominent in this paper. On the other side, tool life and wear analyses can be studied in future investigations.

It was indicated that the milling forces of the clay-added AA7075 syntactic foams, depending on the cutting parameters, can be anticipated through artificial neural network modeling.

It is hoped that analyzing the influence of the cutting parameters using neural network models on the slot milling forces of metallic syntactic foams (MSFs) will be notably useful for research and development (R&D) researchers and design engineers.

This work is the first investigation that focuses on the estimation of slot milling forces of the expanded clay-added AA7075 syntactic foams by using different artificial neural network modeling approaches.

Intent detection (ID) and slot filling (SF) are two important tasks in natural language understanding. ID is to identify the main intent of a paragraph of text. The goal of SF is to extract the information that is important to the intent from the input sentence. However, most of the existing methods use sentence-level intention recognition, which has the risk of error propagation, and the relationship between intention recognition and SF is not explicitly modeled. Aiming at this problem, this paper proposes a collaborative model of ID and SF for intelligent spoken language understanding called ID-SF-Fusion.

ID-SF-Fusion uses Bidirectional Encoder Representation from Transformers (BERT) and Bidirectional Long Short-Term Memory (BiLSTM) to extract effective word embedding and context vectors containing the whole sentence information respectively. Fusion layer is used to provide intent–slot fusion information for SF task. In this way, the relationship between ID and SF task is fully explicitly modeled. This layer takes the result of ID and slot context vectors as input to obtain the fusion information which contains both ID result and slot information. Meanwhile, to further reduce error propagation, we use word-level ID for the ID-SF-Fusion model. Finally, two tasks of ID and SF are realized by joint optimization training.

We conducted experiments on two public datasets, Airline Travel Information Systems (ATIS) and Snips. The results show that the Intent ACC score and Slot F1 score of ID-SF-Fusion on ATIS and Snips are 98.0 per cent and 95.8 per cent, respectively, and the two indicators on Snips dataset are 98.6 per cent and 96.7 per cent, respectively. These models are superior to slot-gated, SF-ID NetWork, stack-Prop and other models. In addition, ablation experiments were performed to further analyze and discuss the proposed model.

This paper uses word-level intent recognition and introduces intent information into the SF process, which is a significant improvement on both data sets.

This paper aims to propose a semianalytical model of a squirrel-cage induction machine (SCIM), considering local magnetic saturation and eddy-currents induced in the rotor bars.

The regions of the rotor and stator are divided into elementary subdomains (E-SDs) characterized by general solutions at the first harmonic of the magneto-harmonic Maxwell’s equations. These E-SDs are connected in both directions (i.e., along the r- and θ-edges).

The calculation of the magnetic field has been validated for various values of slip and iron permeability. All electromagnetic quantities were compared with those obtained using a two-dimensional finite-element method. The semianalytical results are satisfactory compared with the numerical results, considering both the amplitude and waveform.

Expansion of the recent analytical model (E-SD technique) for the full prediction of the magnetic field in SCIMs, considering the local saturation effect and the eddy-currents induced in the rotor bars.

This paper seeks to understand users' perceptions of their experiences in mobile applications (apps) with gamified loyalty programs (GLPs) that use rewards as the primary engagement vehicle. The research focuses particularly on the motivations to further interact with GLPs and the motivational changes occurring after successive interactions.

The authors conducted weekly open qualitative interviews over a month (four rounds of interviews) with five Portuguese active users of the mobile app Yorn Shake It, from Vodafone, which is a relevant case study to illustrate GLPs in mobile apps.

Participants' motivations to interact with the mentioned GLP are shaped by the reward incentive and users' perceptions of the gamified interactive experience. Motivational changes occur regardless of the presence of external contingencies and depend on contextual changes or perceived results of the gamified experience. This means that rewards also satisfy intrinsic needs, but users may remain connected to the system as long as fun experiences are provided without exhausting perceptions. Also, motivation may turn to reward contingencies when the challenge becomes boring.

This is the first qualitative study explaining the perceptions of gamified experiences after continued participation, extending knowledge about the importance of a fair balance between the value and achievement of rewards and the entertainment of the challenge provided after continued exposure. The findings provide insights to GLP marketing managers and developers to better engage target audiences according to their needs and past experience, creating levels of challenges and fair rewards to maintain motivation and prevent abandonment after continued exposure.

This study aims to understand how free-play credits affect risk-seeking behavior in slot players. Extant results suggest they encourage risk aversion, counter to the primary aim of increasing spend per visit. The results inform operators as to the effectiveness of what has become the primary play incentive for casino marketers within many of the world’s markets.

Within a quasi-experimental grouped design, 365 days of player-level performance data from four different casinos were analyzed to determine whether player losses (casino revenues) and time played differed on visits that included free-play redemptions from those that did not. Hypotheses were tested via paired-samples t-tests and Mann–Whitney U tests.

On balance, neither player losses nor time played were significantly different on the free-play visits. Neither the house money effect nor the endowment effect was supported. The results were most consistent with the prospect-theory-with-memory editing rule. No findings indicated increased risk-seeking behavior associated with the free-play offers.

Casino operators are afforded insight related to how costly free-play campaigns affect gaming spend and playtime. Both are critical to understanding the impact of free-play on the gambler’s experience.

The 365-day samples extended existing research by analyzing the impact of free-play offers on risk-taking behaviors within the scope of a perpetual/ongoing campaign. Comparisons of observed daily behavior/outcomes were made between separate tiers of like-kind gamblers from each of four different casinos. Quasi-hedonic editing rules were applied to a multistage decision framework.

This study aims to examine the problems of the concession system that Macao has long-term adopted to regulate its gaming industry and discuss alternatives.

Theoretical reflection was used to provide qualitatively different insights about governmental supervision of the gaming industry.

Two options for reform are proposed: (1) replace the concession system with a licensing system that does not restrict the number of concessionaires or the period of concession or (2) adopt a modified form of the concession system that changes the number of concessionaires, period of concessions and methods for selecting concessionaires.

This study’s results have implications for the Macao government and other gaming jurisdictions in Asia.

This study provides a comprehensive examination of the concession system for governmental supervision of the gaming industry.

Although existing studies provide valuable insight into how destinations create stimuli that support meaningful experiences, perceptions of different experiencescapes in the tourism context remain to be explored. This research aims to explore the experiencescape stimuli of female digital nomads.

The study adopted a qualitative research method and was structured by combining multiple qualitative data collection tools with a triangulated approach to examining the experiencescape.

Based on the experiences of female digital nomads toward destinations, their perception of the experiencescape, which includes sensory, functional, social, natural and cultural stimuli, has been revealed. From the explanations regarding the metaphors, the female digital nomads in the research have positive perceptions about destination experiences and are satisfied with being digital nomads.

The fact that the research is the first to focus on digital nomadism and experiencescape and that it reveals the perspective of female digital nomads who share their experiences in virtual communities, which is a research topic that is little emphasized in the literature, is a contribution to the theoretical framework on the subject. The practical contribution is that it will guide studies to improve and re-plan experiences in line with the stimuli emphasized by the female digital nomads studied. The results can play a supporting role in developing the market for female digital nomads.

This research offers a new perspective on exploring female digital nomads' perceptions of the destination experiencescape.

The social and economic importance esports has gained over the past decades has led to a quickly evolving academic interest in the topic. Yet, current perspectives on esports frequently are not precise enough, too context-specific and/or focus on the question whether esports is sports or not. This means that no precise structural concept has been provided thus far. Such a conceptualization as well as a categorization of esports and related types of video gaming are provided in this paper.

This paper is based on a narrative review considering academic literature from 2000 to 2021 and publications of relevant esports organizations. The review is conceptually extended by structural parallels to traditional sports.

The central outcome of this research is conceptualizing esports as a victory-driven, organized performance comparison of exclusively human players playing video games in a competitive setting. This comparison is based solely on the performance achieved during a defined time frame according to fixed rules with comparably equal team (starting) conditions. This conceptualization is embedded in a general categorization of video gaming based on structural similarities with and differences to esports. Moreover, characteristics that were rejected in regards to the conceptualization and the categorization are discussed.

This paper provides a comprehensive categorization of esports and other types of video gaming based on structural similarities and differences. It is thus of high relevance for academia and sport management practice alike and can further the development in both fields.

The electromechanical planetary transmission system has the advantages of high transmission power and fast running speed, which is one of the important development directions in the future. However, during the operation of the electromechanical planetary transmission system, friction and other factors will lead to an increase in gear temperature and thermal deformation, which will affect the transmission performance of the system, and it is of great significance to study the influence of the temperature effect on the nonlinear dynamics of the electromechanical planetary system.

The effects of temperature change, motor speed, time-varying meshing stiffness, meshing damping ratio and error amplitude on the nonlinear dynamic characteristics of electromechanical planetary systems are studied by using bifurcation diagrams, time-domain diagrams, phase diagrams, Poincaré cross-sectional diagrams, spectra, etc.

The results show that when the temperature rise is less than 70 °C, the system will exhibit chaotic motion. When the motor speed is greater than 900r/min, the system enters a chaotic state. The changes in time-varying meshing stiffness, meshing damping ratio, and error amplitude will also make the system exhibit abundant bifurcation characteristics.

Based on the principle of thermal deformation, taking into account the temperature effect and nonlinear parameters, including time-varying meshing stiffness and tooth side clearance as well as comprehensive errors, a dynamic model of the electromechanical planetary gear system was established.