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This paper aims to present a sliding mode control method based on disturbance observer (DO) for improving the reaching law of permanent magnet synchronous motor (PMSM).

Aiming at the insufficiency of the traditional exponential reaching law used in sliding mode variable structure control, an exponential reaching law related to the speed error is proposed. The improved exponential reaching law can adaptively adjust the size of the constant velocity term in the reaching law according to the size of the speed error, so as to adaptively adjust the speed of the system approaching the sliding mode surface to overcome the control deviation and improve the dynamic and steady state performance. To improve the anti-interference ability of the system, a DO is proposed to observe the external disturbance of the system, and the observed value is used to compensate the system. The stability of the system is analyzed by Lyapunov theorem. The effectiveness of this method is proved by simulation and experiment.

Simulation and experiment show that the proposed method has the advantages of fast response and strong anti-interference ability.

The proposed method cannot observe the disturbance caused by the change of internal parameters of the system.

A sliding mode control method for PMSM is proposed, which has good control performance. The proposed method can effectively suppress chattering, ensure fast response speed and have strong anti-interference ability. The effectiveness of the algorithm is verified by simulation and experiment.

The purpose of this study is to explore the impact of the robot restaurant servicescape and robot service competence (RSC) on customers’ behavioral intentions and to analyze the mediating role of hedonic value (HV) and utilitarian value (UV) in these relationships and the moderating role of individual characteristics.

This research involves seven constructs to be measured, namely, servicescape, RSC, negative attitude toward robots (NAR), openness to change (OC), HV, UV and behavioral intention. This research selects Foodom robot restaurants, located in Shunde and Guangzhou of China, as the research site, and the research objects are customers having dinner in the restaurant. A total of 485 valid data was collected. Structural equation modeling was used to analyze the data, verify the proposed research model, and test the research hypotheses.

The study finds that servicescape and RSC improve customer behavioral intention. Additionally, HV and UV mediate the influence of servicescape and RSC on customer behavioral intention. Moreover, OC negatively moderates the influence of servicescape on UV and that a NAR negatively moderates the influence of RSC on HV.

Through carefully design of servicescape and the improvement in service capabilities of robots, the original service delivery dominated by frontline service personnel can be transformed into service delivery dominated by service robots, which is conductive to providing a pleasant and unforgettable experience for customers.

Presents a brief introduction to the development of librarianship in China, describes the environment in which academic libraries exist in mainland China today, summarising their new features. They are digitising and networking information resources and services. Problems are identified and suggestions made for overcoming them. Provides lists of some academic library homepages and networks.

This paper aims to show a resin-flowing model based on Darcy’s law to display the flowing properties of prepreg during lamination. The conformity between the model and experimental results demonstrates that it can provide a guideline on print circuit board (PCB) lamination.

Based on the theoretical derivations of Darcy’s law, this paper made an analysis on the flow of prepreg in the pressing process, according to which a theoretical model, namely, resin-flowing model was further formulated.

This paper establishes a resin-flowing model, according to which two experiment-verified conclusions can be drawn: first, the resin-flowing properties of material A and B can be improved when the heating rate is between 1.5 and 2.5 min/°C; second, increased pressure gradient can add the amount of flowing resin, mainly featured by increasing pressure and reducing filled thickness of prepreg.

This model provides guidance on setting lamination parameters for most kinds of prepregs and decreasing starvation risk for PCB production.

The purpose of this study is to examine Bitcoin's price behavior across market conditions, focusing on the influence of Bitcoin's historical prices, news sentiment and market indicators like oil prices, gold and the S&P index. The authors also assess the stability of Bitcoin-inclusive hedging portfolios under different market conditions, for example, bearish, bullish and moderate market states.

This study uses the Quantile Autoregressive Distributed Lag model to explore the effects of different factors on Bitcoin's prices across various market situations. This method allows for a detailed analysis of historical trends, investor expectations and external market influences on Bitcoin's price movements and systematic stability.

Key findings reveal historical prices and investor expectations significantly influence Bitcoin in all market scenarios, with news sentiment exhibiting substantial volatility. This study indicates that oil prices have minimal impacts on Bitcoin, whereas gold is a stabilizing asset in bear markets, with the S&P index influencing short-term fluctuations. At the same time, Bitcoin's volatility varies with market conditions, proving more efficient as a hedging tool in bear and stable markets than in bull ones.

This study highlights the intrinsic correlation between Bitcoin's prices, news sentiment and financial market indicators, enhancing understanding of Bitcoin's market dynamics. The authors demonstrate Bitcoin's weak direct correlation with commodities like oil, the stabilizing role of gold in crypto portfolios and the stock market's indirect effect on Bitcoin prices. By examining these factors' impacts across various market conditions, the findings offer strategies for investors to improve hedging and portfolio management in cryptocurrency markets.

This study aims to explore the key attributes of robot chef restaurants and their influencing factors from the perspective of customers and analyzes how these key attributes affect customer perceived value.

A mixed-methods research design was used in this study. Using 473 online reviews and ratings (Study 1), the research summarized customers’ evaluations on three types of attributes (environment, service and food) and identified the key attributes along with their influencing factors. Subsequently, through field questionnaires (Study 2) involving 269 actual customers, structural equation modeling was used to analyze how the identified key attributes and their influencing factors impact customer perceived value.

This study reveals that customers in robot chef restaurants prioritize food attributes, particularly valuing food authenticity alongside food quality. In contrast to traditional restaurants, customers’ evaluations of food attributes in robot chef restaurants are significantly influenced by the competence of robot chefs. Notably, customers’ negative attitudes toward robots diminish the positive effects on both food quality and food authenticity.

To enhance customer perceived value, robot chef restaurants should concentrate on food attributes. They can achieve this by fostering a high-quality, authentic food experience through the elevation of robot chefs’ competence and by providing customer education.

This study expands research on the customer experience in robotic restaurants by proposing an integrated model determining factors that affect the perceived customer value.

This article investigates the renaming of departments of library and information science (LIS) in China in the 1990s. It analyses the technological, economic, social and government factors which affect education for LIS in contemporary China. Problems facing education for LIS in China are considered and suggestions made.

Chinese consumers’ cross-border internet shopping, so called “haitao” is an emerging popular trend in China. Haitao can be understood as service innovation process because it creates new market spaces and provides differentiated values for Chinese customers.

This study aims to explore the service innovation strategies and success factors of haitao business in the Chinese market. The authors selected two successful haitao sites of Amazon.cn and Gmarket.co.kr, as representatives of a global player and a niche player, and conducted a comparative case study to analyze their service innovation strategies and key success factors.

This comparative case analysis based on value chain framework revealed some common success factors such as trust, advanced system and alliances as well as their service innovation efforts. Amazon has advantages such as efficient logistics system and global sourcing, whereas Gmarket has advantages such as product category, sales promotions, and payment system.

This study provides some implications for managers with localization, alliances and platform strategies.

The alienation of megaproject environmental responsibility (MER) behavior is destructive, but its mechanism has not been clearly depicted. Based on fraud triangle theory and the fuzzy set qualitative comparative analysis (fsQCA) method, this study explored the combined effect of antecedent factors on alienation of MER behavior.

Based on the fraud triangle theory and literature review, eight influencing factors associated with the alienation of MER behavior were first identified. Subsequently, the fuzzy-set qualitative comparative analysis was used in this study to reveal configurations influencing alienation of MER behavior.

The study found nine configurations of MER behavioral alienation antecedent factors, integrated into three types of driving modes, i.e. “economic pressure + learning effect,” “institutional defect + moral rejection,” and “information asymmetry + economic pressure + expectation pressure.”

By analyzing the configuration effects of various induced conditions, this study puts forward a comprehensive analysis framework to solve the alienation of MER behavior in the megaprojects and a practical strategy to control alienation of MER behavior.

Epoxy (EP) and polye-caprolactone (PCL) are typical dual-shape memory polymer (DSMP). To get excellent triple-shape memory effect (TSME) polymer composites which are made from EP and PCL. Miscible PCL/EP blend composites have been investigated and compared to the TSMEs with electrospun PCL microfiber membranes/EP composites. Clay montmorillonite (MMT)-modified electrospun PCL microfiber membranes were prepared to improve the shape memory fixities of electrospun PCL microfiber membranes/EP composites.

The morphologies of electrospun PCL microfiber membranes and the cross section of PCL/EP composites were studied using a field emission scanning electron microscope (FE-SEM), and the existence of MMT was confirmed by a transmission electron microscope. Thermal mechanical properties were observed by a differential scanning calorimeter (DSC) and a dynamic thermomechanical analysis machine, and the TSMEs were also determined through dynamic mechanical analysis.

Results indicate that the TSMEs of electrospun PCL microfiber membranes/EP composites were excellent, whereas the TSMEs of PCL/EP blend composites were poor. The TSMEs of PCL electrospun microfiber membranes/EP composites significantly improved with the addition of the PCL electrospun microfiber modified with moderate MMT.

Adding a moderate content of MMT into the electrospun PCL fibers, could improve the TSME of the PCL fiber membranes/EP composites. This study was to create a simple and effective method that can be applied to improve the performance of other SMP.

A novel triple-shape memory composite were made from dual-shape memory EP and electrospun PCL fiber membranes.