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Walking on inclined ground is an important ability for humanoid robots. In general, conventional strategies for walking on slopes lack technical analysis in, first, the waist posture with respect to actual robot and, second, the landing impact, which weakens the walking stability. The purpose of this paper is to propose a generic method for walking pattern generation considering these issues with the aim of enabling humanoid robot to walk dynamically on a slope.

First, a virtual ground method (VGM) is proposed to give a continuous and intuitive zero-moment point (ZMP) on slopes. Then, the dynamic motion equations are derived based on 2D and 3D models, respectively, by using VGM. Furthermore, the waist posture with respect to the actual robot is analyzed. Finally, a reformative linear inverted pendulum (LIP) named the asymmetric linear inverted pendulum (ALIP) is proposed to achieve stable and dynamical walking in any direction on a slope with lower landing impact.

Simulations and experiments are carried out using the DRC-XT humanoid robot platform with the aim of verifying the validity and feasibility of these new methods. ALIP with consideration of waist posture is practical in extending the ability of walking on slopes for humanoid robots.

A generic method called ALIP for humanoid robots walking on slopes is proposed. ALIP is based on LIP and several changes, including model analysis, motion equations and ZMP functions, are discussed.

The purpose of this study is to analyze the short-term development pattern and long-term development trend of the digital supply chain.

This study uses the combination of short-term game and long-term evolutionary game theory.

Findings of this study suggest that irrational decisions can make the evolutionary path of the digital supply chain complex and unpredictable.

This study proposes an evolutionary game model for the digital supply chain that can provide good guidance for the digitalization process of enterprises.

To provide valuable information for scholars to grasp the current situations, hotspots and future development trends of reliability analysis area.

In this paper, recent researches on efficient reliability analysis and applications in complex engineering structures like aeroengine rotor systems are reviewd.

The recent reliability analysis advances of engineering application in aeroengine rotor system are highlighted, it is worth pointing out that the surrogate model methods hold great efficiency and accuracy advantages in the complex reliability analysis of aeroengine rotor system, since its strong computing power can effectively reduce the analysis time consumption and accelerate the development procedures of aeroengine. Moreover, considering the multi-objective, multi-disciplinary, high-dimensionality and time-varying problems are the common problems in various complex engineering fields, the surrogate model methods and its developed methods also have broad application prospects in the future.

For the strong demand for efficient reliability design technique, this review paper may help to highlights the benefits of reliability analysis methods not only in academia but also in practical engineering application like aeroengine rotor system.

This paper aims to investigate the responses of single piles and pile groups due to tunneling-induced ground movements in a two-layered soil system. The analyses mainly focus on the additional single pile responses in terms of bending moment, lateral deflection, axial force, shaft resistance and pile settlement. Subsequently, a series of parametric studies were carried out to better understand the responses of single piles induced by tunneling. To give further understanding regarding the pile groups, a 2 × 2 pile group with two different pile head conditions, namely, free and capped, was considered.

Using the PLAXIS three-dimensional (3D) software, a full 3D numerical modeling is performed to investigate the effects of ground movements caused by tunneling on adjacent pile foundations. The numerical model was validated using centrifuge test data found in the literature. The relevance of the 3D model is also judged by comparison with the 2D plane strain model using the PLAXIS 2D code.

The numerical test results reveal that tunneling induces significant displacements and internal forces in nearby piles. The magnitude and distribution of internal forces depend mainly on the position of the pile toe relative to the tunnel depth and the distance between the pile and the vertical axis of the tunnel. As the volume loss increases from 1% to 3%, the apparent loss of pile capacity increases from 11% to 20%. By increasing the pile length from 0.5 to 1.5 times, the tunnel depth, the maximum pile settlement and lateral deflection decrease by about 63% and 18%, respectively. On the other hand, the maximum bending moment and axial load increase by about 7 and 13 times, respectively. When the pile is located at a distance of 2.5 times the tunnel diameter (Dt), the additional pile responses become insignificant. It was found that an increase in tunnel depth from 1.5Dt to 2.5Dt (with a pile length of 3Dt) increases the maximum lateral deflection by about 420%. Regarding the interaction between tunneling and group of piles, a positive group effect was observed with a significant reduction of the internal forces in rear piles. The maximum bending moment of the front piles was found to be higher than that of the rear piles by about 47%.

Soil is a complex material that shows differently in primary loading, unloading and reloading with stress-dependent stiffness. This general behavior was not possibly being accounted for in simple elastic perfectly plastic Mohr–Coulomb model which is often used to predict the behavior of soils. Thus, in the present study, the more advanced hardening soil model with small-strain stiffness (HSsmall) is used to model the non-linear stress–strain soil behavior. Moreover, unlike previous studies THAT are usually based on the assumption that the soil is homogeneous and using numerical methods by decoupled loadings under plane strain conditions; in this study, the pile responses have been exhaustively investigated in a two-layered soil system using a fully coupled 3D numerical analysis that takes into account the real interactions between tunneling and pile foundations. The paper presents a distinctive set of findings and insights that provide valuable guidance for the design and construction of shield tunnels passing through pile foundations.

The purpose of this paper is to report on the stabilization network optimization of internally matched GaN high electron mobility transistors (HEMTs).

The effects of the two stabilization networks on the characteristics of the device are discussed, such as the stability, power gain and output power.

With the optimized stabilization network, the internally matched GaN HEMTs with 16‐mm gate width exhibited good stability and delivers a 46 dBm output power with 6.1 dB power gain under the continuous wave condition at 8 GHz. By using the optimized stabilization network, the package process of the large‐scale microwave power device of GaN HEMTs can be simplified.

This paper provides useful information for the internally matched GaN HEMTs.

This chapter is building conceptual background of psychological risk for international tourists. Drawing on Place Attachment Theory, Moral Disengagement Theory, Followership Theory, Job Demands-Resources, Acculturation Theory and Goal Progress Theory of Rumination, this chapter proposes a framework of psychological risks with six psychological risks that tourists could encounter in foreign destination: destination detachment risk, moral disengagement risk, risk of false risk assessment, burnout risk, risk of loneliness and risk of rumination. High destination detachment could lead tourists to behave less environmentally friendly, while high moral disengagement could lead tourists to behave less ethically friendly. Followership to the influencers in social media could lead tourists to engage in risk-taking behaviours and false risk assessment, leading to burnout risk, risk of loneliness and risk of rumination, where negative autobiographical memory is created and forming memory-related distress when they arrive homes. Place detachment and moral disengagement risk local environmental and social health, while burnout, loneliness and rumination pose risks for the tourists' psychological health. Several studies propose suggestions for the destination manager and tourists to manage the risk effectively and adequately, including place attachment and moral engagement campaign, careful travel planning and social support.

Decision-making in human resources management is done at both the micro and macro level of organizations. Unfortunately, the decisions at each level are often executed without consideration of the other, and current theory reflects this issue. In response to a call for integration of micro- and macro-level processes by Huselid and Becker (2011), we review the extant literature on strategic human resources and high-performance work systems to provide recommendations for both research and practice. We aimed to contribute to the literature by proposing the incorporation of the situation awareness literature into the high-performance work systems framework to encourage the alignment of human resources efforts. In addition, we provide practical recommendations for integrating situation awareness and strategic decision-making. We discuss a process for the employment of situation awareness in organizations that might not only streamline human resources management but also result in more effective decisions. Additional considerations include implications for teams, boundary conditions (e.g., individual differences), and measurement.

Project portfolio risk (PPR) management plays an important role in promoting the smooth implementation of a project portfolio (PP). Accurate PPR prediction helps managers cope with risks timely in complicated PP environments. However, studies on accurate PPR impact degree prediction, which consists of both risk occurrence probabilities and risk impact consequences considering project interactions, are limited. This study aims to model PPR prediction and expand PPR prediction tools.

In this study, the authors build a PPR prediction model based on a genetic algorithm and back-propagation neural network (GA-BPNN) integrated with entropy-trapezoidal fuzzy numbers. Then, the authors verify the proposed model with real data and obtain PPR impact degrees.

The test results indicate that the proposed method achieves an average absolute error of 0.002 and an average prediction accuracy rate of 97.8%. The former is reduced by 0.038, while the latter is improved by 32.1% when compared with the results of the original BPNN model. Finally, the authors conduct an index sensitivity analysis for identifying critical risks to effectively control them.

This study develops a hybrid PPR prediction model that integrates a GA-BPNN with entropy-trapezoidal fuzzy numbers. The authors use this model to predict PPR impact degrees, which consist of both risk occurrence probabilities and risk impact consequences considering project interactions. The results provide insights into PPR management.

Social shopping website (SSW) introduce the social side into the shopping process, thus making “window” shopping or browsing more interesting for customers. The purpose of this paper is to investigate customer online browsing experience and its antecedents (i.e. information quality and social interaction) and consequences (i.e. urge to buy impulsively and continuous browsing intention) in the context of SSW.

A survey questionnaire was distributed to visitors of online SSW to collect data, and partial least squares technology was used to test the research model.

The results of this study reveal that three types of web browsing, namely, utilitarian browsing, hedonic browsing and social browsing, take place in a SSW. The unique factors of SSW, namely, the quality of user generated contents and social interaction are critical for facilitating customers’ browsing experiences. Furthermore, the findings reveal that hedonic browsing experience is found to be the most salient factor influencing customers’ urge to buy impulsively and continuance intention.

The findings suggest that practitioners, such as designers and managers of SSW should give special attention to the benefits of browsing activity to convert web browsers into impulse purchasers and increase customers’ loyalty. Moreover, they should focus on improving the quality of user generated content and pay more attention to support and encourage social interaction to enhance browsing experiences on a SSW.

Existing studies about browsing behavior mostly focus on traditional online e-commerce website. This study represents the first step toward understanding browsing activity on SSW. Moreover, prior studies mainly focused on utilitarian and hedonic browsing experience; however, there is a lack of research on social browsing experience. The current study attempts to fill this research gap.

Augmented reality (AR) has become a trend, and the effects of Pokémon Go, the most popular online and mobile game, have been explored in many studies. However, few studies have developed questionnaires of fit to investigate the relationship between the fit and the integration of the game's virtual world and reality. The paper intends to integrate the models of stimulus-organism-response (S-O-R) and information systems success with cognitive fit theory to explore the fit and reactions of users in the integration of real and virtual worlds.

Following MacKenzie's scale development, two surveys were conducted. The first survey was conducted to perform a scale development of fit. The second survey was collected from 315 Pokémon Go players to validate the fit scale and it was analyzed via structural equation modeling.

The results show that scale development of fit has good reliability and validity. Furthermore, game information quality, game system quality and virtual (Pokémon) characteristics have significantly positive effects on cognitive and emotional fit. Cognitive and emotional fit have significant positive effects on user satisfaction, and user satisfaction has significant positive effects on continued intention to play. The results suggest that maintaining the quality of the game and improving the virtual interface will provide a better fit between the real and virtual worlds, enhancing user satisfaction with the fit as well as their intention for continued use.

Although fit has been widely studied in various contexts, the application of AR has been rarely discussed. This study develops a scale of fit and takes Pokémon Go as the subject to validate the fit measurement and discuss players' cognition and feelings regarding the game. The authors measure user reactions to different stimuli and explore cognitive and emotional fit as well as the integration of virtual worlds and reality. In sum, to the best of the authors’ knowledge, this is one of the earliest studies to explore and develop a cognitive and emotional fit scale for future researchers and practitioners.