Search results

This paper aims to propose and verify an improved cascade active disturbance rejection control (ADRC) scheme based on output redefinition for hypersonic vehicles (HSVs) with nonminimum phase characteristic and model uncertainties.

To handle the nonminimum phase characteristic, a tuning factor stabilizing internal dynamics is introduced to redefine the system output states; its effective range is determined by analyzing Byrnes–Isidori normalized form of the redefined system. The extended state observers (ESOs) are used to estimate the uncertainties, which include matched and mismatched items in the system. The controller compensates observations in real time and appends integral terms to improve robustness against the estimation errors of ESOs.

Theoretical and simulation results show that the stability of internal dynamics is guaranteed by the tuning factor and the tracking errors of external commands are globally asymptotically stable.

The control scheme in this paper is expected to generate a reliable way for dealing with nonminimum phase characteristic and model uncertainties of HSVs.

In the framework of ADRC, a concise form of redefined outputs is proposed, in which the tuning factor performs a decisive role in stabilizing the internal dynamics of HSVs. By introducing an integral term into the cascade ADRC scheme, the compensation accuracy of matched and mismatched disturbances is improved.

To develop electrode materials for supercapacitor with superior electrochemical performance and simple preparation process, the purpose of this study is to prepare flexible CC/NiS/a-NiS electrodes with self-supporting structure by loading hydrothermally synthesized a-NiS particles along with nano-NiS on carbon cloth by electroplating method.

The effects of current densities, temperatures and pH values on the loading amount and uniformity of the active substances during the plating process were investigated on the basis of optimization of surface morphology, crystalline structure and electrochemical evaluation as the cyclic voltammetry curves, constant current charge–discharge curves and AC impedance.

The a-NiS particles on CC/NiS/a-NiS were mostly covered by the plated nano-NiS, which behaved as a bulge and provided a larger specific surface area. The CC/NiS/a-NiS electrode prepared with the optimized parameter exhibited a specific capacitance of 115.13 F/g at a current density of 1 A/g and a Coulomb efficiency of 84% at 5 A/g, which is superior to that of CC/NiS electrode prepared by electroplating at a current density of 10 mA/cm², a temperature of 55°C and a pH of 4, demonstrating its fast charge response of the electrode and potential application in wearable electronics.

This study provides an integrated solution for the development of specifically structured NiS-based electrode for supercapacitor with simple process, low cost and high electrochemical charge/discharge performance, and the simple and easy-to-use method is also applicable to other electrochemically active composites.

This study investigates CSR reporting’s role in debt access and cost of debt with the moderating role of external assurance and GRI adoption in emerging markets. Such an investigation will help facilitate external fund flow to firms in better terms.

We collected data from 16 emerging markets between 2008 and 2019 from the Thomson Reuters Eikon and ran fixed effects regression analysis and robustness tests by addressing endogeneity concerns, adopting alternative sample and integrating additional control variables.

The results show that CSR reporting has a positive association with access to debt and a negative association with the cost of debt. Furthermore, both external assurance and GRI adoption do not significantly moderate between CSR reporting and access to debt and cost of debt. Hence, creditors in emerging markets are not interested in CSR report assurance and GRI framework adoption and do not integrate them into their lending decisions.

Emerging markets are unique settings characterized by high growth rates, limited capital availability, high debt costs and weak institutional environments. Thus, reaching debt with convenient conditions is critical for emerging market firms to finance their growth. Hence, our study will help emerging market firms reach external funding more easily and in better terms via CSR transparency. Besides, our investigation is based on a broad sample of emerging markets, and hence updates prior emerging market studies conducted in single-country settings. Lastly, we test the complementarity of third-party assurance and GRI adoption to CSR reporting in loan contracting.

This study aims to examine the risk-resistant role of environmental, social and governance (ESG) performance in the capital market, focusing on an organizational standpoint. Furthermore, it aims to offer management decision advice to companies seeking protection against stock market risks. Conclusions obtained through this research have the potential to enrich the economic consequences of ESG performance, provide practical implications for enhancing corporate ESG performance, improving corporate information quality and stabilizing capital market development.

Based on the data of Chinese A-share listed companies from 2009 to 2020, this study examines the risk-resistant function of ESG performance in the capital market. The impact of ESG performance on management behavior is analyzed from the perspective of organizational management and the three mechanisms of pre-event, during the event and post-event.

This paper demonstrates that companies that effectively implement ESG practices are capable of effectively mitigating risks associated with stock price crashes. Heterogeneity analysis reveals that the inhibitory effect of ESG performance on stock price crash risk is more pronounced in nonstate-owned enterprises and enterprises with higher levels of marketization. After controlling for issues such as endogeneity, the conclusions of this paper are still valid. The mechanism analysis indicates that ESG performance reduces the risk of stock price crash through three paths of organizational management: pre-event, during the event and post-event. That is, ESG performance plays the role of restraining managers’ opportunistic behavior, reducing information asymmetry and boosting investor sentiment.

This paper provides new insights into the relationship between ESG performance and stock price crash risk from an organizational management perspective. This study establishes three impact mechanisms (governance effect, information effect and insurance effect), offering a theoretical basis for strategic corporate decisions of risk management. Additionally, it comprehensively examines the contextual differences in the role of ESG performance, shedding light on the specific domains where ESG practices are influential. These findings offer valuable insights for promoting stable development in the capital market and fostering the healthy growth of the real economy.

In the context of Industry 4.0, intelligent construction technologies (ICT) represented by information technology and networking will undoubtedly provide new impetus to the development of the prefabricated building supply chain (PBSC), but they will also bring various potential risks. So far, there is a large lack of research on the comprehensive consideration of the risks associated with the intelligent transformation of PBSC based on the information sharing perspective, and the critical risks and interactions are still unclear, making it difficult to identify efficient risk mitigation strategies. Therefore, this paper aims to reveal the interactions between stakeholders and clarify the critical risk nodes and interactions in information sharing of PBSC (IS-PBSC), and propose targeted risk mitigation strategies.

Firstly, this paper creatively delineates the risks and critical stakeholders of IS-PBSC. Secondly, Data is collected through questionnaires to understand the degree of risks impact. Thirdly, with the help of NetMiner 4 software, social network analysis is conducted and IS-PBSC risk network is established to reveal critical risk nodes and interactions. Finally, further targeted discussion of critical risk nodes, the effectiveness and reasonableness of the risk mitigation strategies are proposed and verified through NetMiner 4 software simulation.

The results show that the critical risks cover the entire process of information sharing, with the lack of information management norms and other information assurance-related risks accounting for the largest proportion. In addition, the government dominates in risk control, followed by other stakeholders. The implementation of risk mitigation strategies is effective, with the overall network density reduced by 41.15% and network cohesion reduced by 24%.

In the context of Industry 4.0, ICT represented by information technology and networking will undoubtedly provide new impetus to the development of the PBSC, but they will also bring various potential risks. So far, there is a large lack of research on the comprehensive consideration of the risks associated with the intelligent transformation of PBSC based on the information sharing perspective, and the critical risks and interactions are still unclear, making it difficult to identify efficient risk mitigation strategies.

Based on the results of risk network visualization analysis, this paper proposes an ICT-based IS-PBSC mechanism that promotes the development of the integration of ICT and PBSC while safeguarding the benefits of various stakeholders.

This paper aims to concentrate on recent innovations in flexible wearable sensor technology tailored for monitoring vital signals within the contexts of wearable sensors and systems developed specifically for monitoring health and fitness metrics.

In recent decades, wearable sensors for monitoring vital signals in sports and health have advanced greatly. Vital signals include electrocardiogram, electroencephalogram, electromyography, inertial data, body motions, cardiac rate and bodily fluids like blood and sweating, making them a good choice for sensing devices.

This report reviewed reputable journal articles on wearable sensors for vital signal monitoring, focusing on multimode and integrated multi-dimensional capabilities like structure, accuracy and nature of the devices, which may offer a more versatile and comprehensive solution.

The paper provides essential information on the present obstacles and challenges in this domain and provide a glimpse into the future directions of wearable sensors for the detection of these crucial signals. Importantly, it is evident that the integration of modern fabricating techniques, stretchable electronic devices, the Internet of Things and the application of artificial intelligence algorithms has significantly improved the capacity to efficiently monitor and leverage these signals for human health monitoring, including disease prediction.

It is unclear what constitutes the tourism live streaming (TLS) servicescape and how it affects users' travel intention (TI). The study aims to explore the composition of the TLS servicescape, the influence mechanism of the TLS servicescape on users' TI and the formation of users' TI.

Based on stimulus organism response theory (SOR), we develop a mediation model to explore the influence of TLS servicescape on users' TI. This study collected data from 432 Chinese TLS users through an online questionnaire, and we used the structural equation model and the SPSS PROCESS macro to test the proposed model. In addition, we tested the variable relationships using fuzzy-set qualitative comparative analysis (fsQCA).

TLS servicescape is a second-order variable that can be categorized into physical element (PE), social element (SOE), symbolic element (SYE) and natural element (NE). TLS servicescape influences TI by affecting social presence (SP) and customer engagement (CE). The fsQCA reveals seven combinations of PE, SOE, SYE, NE, SP and CE that form a high TI for TLS users.

Using multiple data analysis methods, the study emphasizes the significance of the TLS servicescape for TLS. It explores how to evoke users' TI in TLS and provides a reference for TLS marketing.

With the increasing number of Web services, correct and efficient classification of Web services is crucial to improve the efficiency of service discovery. However, existing Web service classification approaches ignore the class overlap in Web services, resulting in poor accuracy of classification in practice. This paper aims to provide an approach to address this issue.

This paper proposes a label confusion and priori correction-based Web service classification approach. First, functional semantic representations of Web services descriptions are obtained based on BERT. Then, the ability of the model is enhanced to recognize and classify overlapping instances by using label confusion learning techniques; Finally, the predictive results are corrected based on the label prior distribution to further improve service classification effectiveness.

Experiments based on the ProgrammableWeb data set show that the proposed model demonstrates 4.3%, 3.2% and 1% improvement in Macro-F1 value compared to the ServeNet-BERT, BERT-DPCNN and CARL-NET, respectively.

This paper proposes a Web service classification approach for the overlapping categories of Web services and improve the accuracy of Web services classification.

Surface acoustic wave (SAW) sensors have attracted great attention worldwide for a variety of applications in measuring physical, chemical and biological parameters. However, stability has been one of the key issues which have limited their effective commercial applications. To fully understand this challenge of operation stability, this paper aims to systematically review mechanisms, stability issues and future challenges of SAW sensors for various applications.

This review paper starts with different types of SAWs, advantages and disadvantages of different types of SAW sensors and then the stability issues of SAW sensors. Subsequently, recent efforts made by researchers for improving working stability of SAW sensors are reviewed. Finally, it discusses the existing challenges and future prospects of SAW sensors in the rapidly growing Internet of Things-enabled application market.

A large number of scientific articles related to SAW technologies were found, and a number of opportunities for future researchers were identified. Over the past 20 years, SAW-related research has gained a growing interest of researchers. SAW sensors have attracted more and more researchers worldwide over the years, but the research topics of SAW sensor stability only own an extremely poor percentage in the total researc topics of SAWs or SAW sensors.

Although SAW sensors have been attracting researchers worldwide for decades, researchers mainly focused on the new materials and design strategies for SAW sensors to achieve good sensitivity and selectivity, and little work can be found on the stability issues of SAW sensors, which are so important for SAW sensor industries and one of the key factors to be mature products. Therefore, this paper systematically reviewed the SAW sensors from their fundamental mechanisms to stability issues and indicated their future challenges for various applications.

The purpose of this research paper was to determine which needs for incentives influence positive word-of-mouth (PWOM) among international tourists and how these needs differ based on the cultural orientation toward individualism and collectivism.

This research used online surveys to gather data from 959 Australian, US, UK, Japanese and Korean respondents who had visited Beijing. A random sampling method was used, and data were analyzed using SmartPLS 4.0. By adopting the existence relatedness growth theory, the findings explain how cultural orientation affects the impact of needs for incentives in generating PWOM.

Three hypothesized relationships were significant for Australia/UK/USA and Japan/Korea – the effect of needs for incentives on motivation, the effect of motivation on PWOM and the effects of needs for incentives on PWOM were significant and positive for Australia/UK/USA and Japan/Korea. The effect of needs for incentive type on motivation varied across national populations, and the intensity of the effects of needs for incentive type on PWOM was also different. For Australian, UK and the US tourists, the honorary title was the most influential need to stimulate word-of-mouth motivation. The need for cultural learning was the most influential for Japanese and Korean tourists.

This research contributes to the literature by exploring and comparing the needs for incentives that influence PWOM among tourists from the perspective of individualism and collectivism. The results also increase the understanding of the relationships among needs for incentives, motivation and PWOM.

本研究旨在确定哪些激励需求会影响国际旅游者的积极口碑（PWOM）, 以及这些激励方式的影响在个人主义和集体主义文化取向的群体中有何不同。

本研究通过在线调查收集了 959 名曾到访北京的澳大利亚、美国、英国、日本和韩国的国际游客数据。研究采用了随机抽样的方法, 使用 SmartPLS 4.0 对数据进行了分析。基于ERG理论, 本研究解释了文化如何影响激励类型对积极口碑的影响。

研究结果显示, 三个假设关系在澳大利亚/英国/美国和日本/韩国两个群组中均显著, 即激励需求对动机的影响、动机对积极口碑的影响、以及激励需求对积极口碑的影响在澳大利亚/英国/美国和日本/韩国群组中都是显著和正向的。激励需求类型对动机和积极口碑的影响在不同国家群体中存在差异。对于澳大利亚、英国和美国的国际游客, 满足名誉需求的激励对产生积极口碑动机的影响更大。对于日本和韩国的国际游客, 满足文化学习需求的激励对产生积极口碑动机的影响更大。

本研究从个人主义和集体主义的角度, 探讨比较了影响国际旅游者积极口碑的激励需求, 为相关领域研究做出了贡献。研究结果加深了对激励需求、动机和积极口碑之间关系的理解。

El objetivo de esta investigación era determinar qué necesidades de incentivación influyen en el boca a boca positivo (PWOM por sus siglas en inglés) entre los turistas internacionales y cómo difieren estas necesidades en función de la orientación cultural hacia el individualismo y el colectivismo.

Esta investigación utilizó encuestas en línea para recopilar datos de 959 encuestados australianos, estadounidenses, británicos, japoneses y coreanos que habían visitado Pekín. Se empleó un método de muestreo aleatorio y los datos se analizaron con SmartPLS 4.0. Adoptando la teoría del Crecimiento de la Relación con la Existencia (ERG por sus siglas en inglés), los resultados explican cómo afecta la orientación cultural al impacto de las necesidades de incentivos en la generación del PWOM.

Tres relaciones hipotetizadas resultaron significativas en los dos grupos de Australia/Reino Unido/Estados Unidos y Japón/Corea: el efecto de las necesidades de incentivación en la motivación, el efecto de la motivación en la PWOM y los efectos de las necesidades de incentivación en la PWOM fueron significativos y positivos para Australia/Reino Unido/Estados Unidos y Japón/Corea. El efecto del tipo de necesidad de incentivación sobre la motivación varió entre las poblaciones nacionales, y la intensidad de los efectos del tipo de necesidad de incentivos sobre la PWOM también fue diferente. Para los turistas australianos, británicos y estadounidenses, el título honorífico fue la necesidad más influyente para estimular la motivación WOM. La necesidad de aprendizaje cultural fue la más influyente para los turistas japoneses y coreanos.

Esta investigación contribuye a la bibliografía al explorar y comparar las necesidades de incentivación que influyen en la motivación boca a boca entre los turistas desde la perspectiva del individualismo y el colectivismo. Los resultados también aumentan la comprensión de las relaciones entre las necesidades de incentivación, la motivación y el PWOM.