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To remanufacture a disused part, a hybrid process needs to be taken in part production. Therefore, a reasonable machining route is necessary to be developed for the hybrid process. This paper aims to develop a novel process planning algorithm for additive and subtractive manufacturing (ASM) system to achieve this purpose.

First, a skeleton of the model is generated by using thinning algorithm. Then, the skeleton tree is constructed based on topological structure and shape feature. Further, a feature matching algorithm is developed for recognizing the different features between the initial model and the final model based on the skeleton tree. Finally, a reasonable hybrid machining route of the ASM system is generated in consideration of the machining method of each different sub-feature.

This paper proposes a hybrid process planning algorithm for the ASM system. Further, it generates new process planning insights on the hybrid process service provider market.

The proposed process planning algorithm enables engineers to obtain a proper hybrid machining route before product fabrication. And thereby, it extends the machining capability of the hybrid process to manufacture some parts accurately and efficiently.

This study addresses one gap in the hybrid process literature. It develops the first hybrid process planning strategy for remanufacturing of disused parts based on skeleton tree matching, which generates a more proper hybrid machining route than the currently available hybrid strategy studies. Also, this study provides technical support for the ASM system to repair damaged parts.

The contact behaviors of droplets on confined surfaces influence significantly their dynamics and morphological transition induced by the electric field. This paper aims to delve into the electric stress, electric field distribution, flow field and evolution of droplet neck to understand the underlying mechanisms.

Electrohydrodynamics of droplets in confined environment is numerically analyzed based on finite volume method (FVM) combining with volume-of-fluid (VOF) method for two-phase interface capturing. Numerical solutions are obtained through solving electrohydrodynamics model coupling fluid dynamics with electrostatics.

It was found that the droplet neck with high interfacial curvature undergoes different transition depending on the contact angle. At large domain height, the droplets on the surfaces with the contact angle of θ < 90° tend to break up into smaller droplets adhered on top and bottom surfaces. The detachment of droplets is identified when the contact angle is much greater than 90°. Notably, the droplets at θ = 90° exhibit asymmetrical shape evolution, but for other cases there is symmetrical shape of droplets during transition process. With decreasing the domain height, no obvious deformation through driving the contraction of the droplet neck is observed.

It remains unclear how the electric field parallel to the surfaces affects the shape transition and electrohydrodynamics of confined droplets when changing the contact angle. In this paper, the authors study the electrohydrodynamics of droplets in confined space when the electric field is exerted parallel to contact surfaces. In particular, the authors consider the effect of the surface wettability on the droplet deformation. The problem is solved through FVM combining with the VOF method to implement the capturing of two-phase interfaces. The results indicate that the electrohydrodynamic behaviors of droplets are sensitive to the contact properties of droplets on the surfaces, which has not been reported in previous works.

Aiming at the cavitations and noise problem of hydraulic cone valve and based on the radial force analysis of the valve core, the radial deviation of the spool is considered to obtain the changing rules of cavitations and noise.

The solid model of the internal flow field of cone valve is established. The mesh models are divided using ICEM-CFD software. The numerical simulation of the liquid-gas two-phase flow is performed on the cavitation and noise of the flow field inside the cone valve based on FLUENT software. The visible experimental platform for cavitation and noise of hydraulic cone valve is built. According to the contrast of the experimental results, the correctness of the simulation results is verified.

The results show that the radial deviation causes the position of the cavitation accumulates in the valve cavity on the side of the upper cone. In addition, the strength of the cavitation changes slowly with the half cone angle of 45°, and the noise level is the smallest. Furthermore, appropriately increasing the opening degree within a reasonable range can effectively suppress cavitation and reduce the noise level.

The cavitation can be suppressed and the noise level can be reduced by means of changing the three factors, which lays the foundation for the design and theoretical research of the cone valve.

Happiness is an important mental emotion and yet becoming a major health concern nowadays. For this reason, better recognizing the objective understanding of how humans respond to event-related observations in their daily lives is especially important.

This paper uses non-intrusive technology (hyperspectral imaging [HSI]) for happiness recognition. Experimental setup is conducted for data collection in real-life environments where observers are showing spontaneous expressions of emotions (calm, happy, unhappy: angry) during the experimental process. Based on facial imaging captured from HSI, this work collects our emotional database defined as SWU Happiness DB and studies whether the physiological signal (i.e. tissue oxygen saturation [StO2], obtained by an optical absorption model) can be used to recognize observer happiness automatically. It proposes a novel method to capture local dynamic patterns (LDP) in facial regions, introducing local variations in facial StO₂ to fully use physiological characteristics with regard to hyperspectral patterns. Further, it applies a linear discriminant analysis-based support vector machine to recognize happiness patterns.

The results show that the best classification accuracy is 97.89 per cent, objectively demonstrating a feasible application of LDP features on happiness recognition.

This paper proposes a novel feature (i.e. LDP) to represent the local variations in facial StO₂ for modeling the active happiness. It provides a possible extension to the promising practical application.

The purpose of this paper is to propose and demonstrate a new additive manufacturing approach that breaks the layer-based point scanning limitations to increase fabrication speed, obtain better surface finish, achieve material flexibility and reduce equipment costs.

The freeform additive manufacturing approach conceptually views a 3D article as an assembly of freeform elements distributed spatially following a flexible 3D assembly structure, which conforms to the surface of the article and physically builds the article by sequentially forming the freeform elements by a vari-directional vari-dimensional capable material deposition mechanism. Vari-directional building along tangential directions of part surface gives surface smoothness. Vari-dimensional deposition maximizes material output to increase build rate wherever allowed and minimizes deposition sizes for resolution whenever needed.

Process steps based on geometric and data processing considerations were described. Dispensing and forming of basic vari-directional and vari-dimensional freeform elements and basic operations of joining them were developed using thermoplastics. Forming of 3D articles at build rates of 2-5 times the fused deposition modeling (FDM) rate was demonstrated and improvement over ten times was shown to be feasible. FDM compatible operations using 0.7 mm wire depositions from a variable exit-dispensing unit were demonstrated. Preliminary tests of a surface finishing process showed a result of 0.8-1.9 um Ra. Initial results of dispensing wax, tin alloy and steel were also shown.

This is the first time that both vari-directional and vari-dimensional material depositions are combined in a new freeform building method, which has potential impact on the FDM and other additive manufacturing methods.

Human capital is the most important determinant of the Hospitality industry’s success. Executive chefs should be skilled in both management and culinary arts, in addition to ensuring the success of the entire hospitality division. The study aims to understand the competencies of executive chefs in international tourist hotels in Taiwan.

Literature review and behavioral event interviews were conducted with ten executive chefs and executive sous chefs. The modified Delphi method verified the results using 15 experts.

A competency framework was created, with four quadrants – managerial, operational, behaviors and skills – to classify executive chefs’ competencies. Each competency was further divided into sub-competencies – culinary research, emotional control, negotiation skills, job guidance and proactive thinking ability – for 25 items. Quadrants I and II are hard competencies that can be improved through education and training, whereas the third and fourth are soft competencies that require more time for development in workers.

The two-step study developed a competency framework with a practical reference value. The study results could be utilized by human resources managers during their companies’ training, recruitment, selection and promotion.

Besides the Delphi method, a deep behavioral event interview that enabled determining critical competencies was also used to collect data. The results obtained could be used to structure schools’ curricula. Collaborations between the hospitality industry and schools could help develop better curricula and training plans to maximize the availability of educational resources.

This study aims to identify different antecedents and reveal divergent moderating effects of horizontal collectivism, thereby unlocking the asymmetric mechanisms for employees’ brand citizenship behavior (BCB) and negative word-of-mouth (NWOM).

This study uses a survey data set and analyzes it with structural equation modeling along with common latent factor analysis designed to control for common method variance.

BCB is associated with pride at work but not perceived organizational support (POS), so POS drives BCB not directly but indirectly through the emotion of pride at work. In contrast, employees’ NWOM is associated with both POS and frustration, and POS drives NWOM directly and indirectly through the emotion of frustration. Horizontal collectivism has divergent moderating effects that strengthen the relationships of BCB with POS and pride at work and weaken the relationship between employees’ NWOM and frustration.

This study makes two major theoretical contributions to internal branding. First, as a response to the need for an investigation into drivers of employees’ brand-oriented behaviors, it will identify different psychological antecedents and mechanisms for BCB and employees’ NWOM. Second, capturing the potential of horizontal collectivism on employees’ brand-oriented behaviors, this study will reveal the potential divergent moderating effects of horizontal collectivism on BCB and employees’ NWOM. These two contributions will lead to a better understanding of the different mechanisms for employees’ BCB and NWOM.

This paper aims to propose and demonstrate a novel surface plasmon resonance (SPR)-sensing approach by using the fundamental mode beam based on a graded index multimode fiber (GIF). The proposed SPR sensor has high sensitivity and controllable working dynamic range, which expects to solve the two bottlenecks of fiber SPR sensor, including low sensitivity and the difficulty in multichannel detection.

The low-order mode of the GIF to SPR sense, which keeps the sensitivity advantage of the single-mode fiber SPR sensor, is used. By using this new SPR sensor, the effect of light incident angle and gold film thickness on working dynamic range was studied. According to the study results, the smaller is the incident angle, the larger is the SPR working dynamic range and the longer is the resonance wavelength with a fixed gold film thickness; the larger is the gold film thickness, the longer is the resonance wavelength with a fixed grinding angle. After the parameter optimization, the sensitivity of these two parameter-adjusting methods reach 4,442 and 3031 nm/RIU.

When the grinding angle of the GIF increases, the dynamic range of the resonance wavelength increases and has a redshift, sensitivity increases, and the resonance valley becomes more unobvious with a fixed gold film thickness. Similarly, when gold film thickness increases, the dynamic range of the resonance wavelength increases and has a redshift, sensitivity increases, and the resonance valley becomes more unobvious with a fixed grinding angle. These adjusting performance aforementioned lay the foundation for solving of the fiber-based SPR multichannel detection and increasing of the fiber-based SPR sensor sensitivity, which has a good application value.

Motivating users to self-disclose online is significant to the long-term development of social media. Therefore, research on emotional disclosure, a significant form of self-disclosure, is required. By developing a stimulus-organism-response model, this study aims to investigate the mechanisms by which the social media environment affects users' online emotional disclosure.

This paper proposes two dimensions of social media environments, the online interpersonal environment (tie strength and network size) and the online information environment (self-reference). They are hypothesized to stimulate users' internal psychological needs (image management and emotional expression) which in turn will influence their emotional disclosure intentions. Using data from 489 users of WeChat Moments, the authors conduct partial least squares analysis to validate the research model.

The findings show that users' intrinsic psychological needs are stimulated by social media environments, but network size is not correlated with the need for emotional expression. The user's need for emotional expression promotes both positive and negative emotional disclosure intentions. The need for image management has a positive impact on positive emotion disclosure intentions but has a negative impact on negative emotion disclosure intentions.

This study contributes to the understanding of online emotional disclosure. It can also help social media managers create efficient plans to encourage users to create content.

The peer review history for this article is available at: https://publons.com/publon/10.1108/OIR-04-2022-0245.

With the emergence of a variety of communication channels on social media, employees have more opportunities to engage with external stakeholders for or against their organizational brand. In such a context, focusing on negative word-of-mouth (NWOM) as an employee’s negative discretionary brand-oriented behavior, the current study aimed to identify negative emotions that can serve as drivers for NWOM more strongly than for counterproductive workplace behavior (CWB), relying on the discrete emotion perspective. This study also aimed to examine whether employees’ perceived brand knowledge can directly diminish employees’ NWOM and CWB and attenuate the influence of negative emotions.

A questionnaire was used to gather relevant data, which were analyzed by structural equation modeling.

The findings showed that anger was more strongly associated with employees’ NWOM than withdrawal and that envy was more strongly associated with CWB toward individuals than employees’ NWOM. Employees’ perceived brand knowledge was negatively associated with both NWOM and CWB directly and mitigated the association of negative emotions such as anger and envy with CWB, but not with NWOM.

Based on the discrete emotion perspective, the current study explored the relative magnitude of emotional antecedents for employees’ NWOM and conventional CWB. Also, it expanded the previous findings on the positive effects of perceived brand knowledge on the positive outcomes of employees’ actions and its mitigating effects on NWOM and CWB.