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This paper aims to study a neural network-based fault-tolerant controller to improve the tracking control performance of an unmanned autonomous helicopter with system uncertainty, external disturbances and sensor faults, using the prescribed performance method.

To ensure that the tracking error satisfies the prescribed performance, the authors adopt an error transformation function method. A control scheme based on the neural network and high-order disturbance observer is designed to guarantee the boundedness of the closed-loop system. A simulation is performed to prove the validity of the control scheme.

The developed adaptive fault-tolerant control method makes the system with sensor fault realize tracking control. The error transformation function method can effectively handle the prescribed performance requirements. Sensor fault can be regarded as a type of system uncertainty. The uncertainty can be approximated accurately using neural networks. A high-order disturbance observer can effectively suppress compound disturbances.

The tracking performance requirements of unmanned autonomous helicopter system are considered in the design of sensor fault-tolerant control. The inequality constraint that the output tracking error must satisfy is transformed into an unconstrained problem by introducing an error transformation function. The fault state of the velocity sensor is considered as the system uncertainty, and a neural network is used to approach the total uncertainty. Neural network estimation errors and external disturbances are treated as compound disturbances, and a high-order disturbance observer is constructed to compensate for them.

This study aims to explore the emotional landscapes and spatial preferences of digital nomads, focusing on how sentiments expressed in destination reviews influence their mobility and destination choices.

Employing a lexicon-based sentiment analysis of social media comments and reviews, alongside advanced geographical information systems (GIS) mapping techniques, the study analyzes the emotional tones that digital nomads associate with various destinations worldwide.

The analysis reveals significant patterns of emotional sentiments, with trust and joy being predominant in preferred destinations. Spatial patterns identified through GIS mapping highlight the global distribution of these sentiments, underscoring the importance of emotional well-being in destination choice.

Insights from this study offer valuable guidance for Destination Management Organizations (DMOs) in strategic planning, enhancing destination appeal through targeted marketing strategies that resonate with the emotional preferences of digital nomads.

This research introduces a novel approach by integrating sentiment analysis with GIS to map the emotional and spatial dynamics of digital nomadism, contributing a new perspective to the literature on tourism and mobility.

The adoption of mobile payment remains low in certain regions, highlighting the need to identify the factors that enable and inhibit its adoption. This study aims to address this gap by investigating the role of information security, loss aversion and the moderating influence of the herd effect on Inertia and behavioral intentions in the adoption of mobile payment systems.

A structural equation model was developed and tested with 332 valid questionnaires to examine the proposed hypotheses.

The empirical results reveal that information security plays a significant role as an enabler, while loss aversion acts as an inhibitor of mobile payment adoption. Furthermore, the study uncovers the moderating influence of the herd effect on the relationship between Inertia and behavioral intentions.

This study was conducted in a specific region and may not be generalizable to other regions. Future studies could expand the sample size and scope to enhance the external validity of the findings.

This study offers practical implications for mobile payment service providers. Understanding the key enabling and inhibiting factors identified in this study can guide providers in designing and improving their services. Strengthening information security measures can help build trust among potential adopters, while offering incentives can mitigate the impact of loss aversion and encourage early adoption.

The findings of this study have social implications as they contribute to promoting the adoption of mobile payment systems. Increased adoption can enhance financial inclusion and stimulate economic development.

This study provides novel insights into the enabling and inhibiting factors of mobile payment adoption and highlights the moderating role of the herd effect. By shedding light on the influence of social norms on individual behavior in the context of mobile payment adoption, this study contributes to the existing literature and advances our understanding of this phenomenon.

The qualitative approach was applied the discover the optimum answers to the research objectives, which are (1) to understand the cultural and hedonistic characteristics of the (Lanna) Songkran festival; and (2) to examine the dilemma between cultural rituals and hedonistic activity for tourism.

This study used a case study of the Songkran festival in Chiang Mai to examine the dilemma between cultural rituals and hedonism for tourism, which brings lost or misperceived cultural values and identities. The semi-structured interview (SSI) with senior locals and participant observation during the festival was conducted in Chiang Mai, Thailand, to obtain the in-depth phenomena of the existing celebration pattern at the festival.

The study findings show three crucial phenomena that explain characteristics of unsynchronized cultural rituals and hedonistic activities for tourism: (1) the parallel phenomenon between cultural values and celebration practice, (2) the movement of local culture and(3) the hedonistic characteristics of the festival.

The study extends the knowledge on the interplay phenomena between cultural festivals and tourism; also, the involved stakeholders, such as local communities, public sectors and private sectors, can use the study findings in creating policies for using cultural festivals to promote a destination and urban economic development that will minimise cultural values distort while increase tourism economic values.

This study was conducted qualitatively, including SSIs and participant observation at the Songkran festival in Chiang Mai. The study findings were analysed, based on the empirical data, into significant themes representing the characteristics of dilemma phenomena within the festival.

The purpose of this study is to investigate the thermomechanical condition on the shape memory property of Polybutylene adipate-co-terephthalate (PBAT). PBAT is a widely researched and rapidly developed biodegradable copolyester. In a tensile test, we found that the fractured PBAT samples had a heat-driven shape memory effect which piqued our interest, and it will lay a foundation for the application of PBAT in new fields (such as heat shrinkable film).

The shape memory effect of PBAT and the effect of the thermomechanical condition on its shape memory property were confirmed and systematically investigated by a thermal mechanical analyzer and tensile machine.

The results showed that the PBAT film had broad shape memory transform temperature and exhibited excellent thermomechanical stability and shape memory properties. The shape memory fixity ratio (Rf) of the PBAT films was increased with the prestrain temperature and prestrain, where the highest Rf exceeded 90%. The shape memory recovery ratio (Rr) of the PBAT films was increased with the shape memory recovery temperature and decreased with the prestrain value, and the highest Rr was almost 100%. Moreover, the PBAT films had high shape memory recovery stress which increased with the prestrain value and decreased with the prestrain temperature, and the highest shape memory recovery stress can reach 7.73 MPa.

The results showed that PBAT had a broad shape memory transform temperature, exhibited excellent thermomechanical stability and shape memory performance, especially for the sample programmed at high temperature and had a larger prestrian, which will provide a reference for the design, processing and application of PBAT-based heat shrinkable film and smart materials.

This study confirmed and systematically investigated the shape memory effect of PBAT and the effect of the thermomechanical condition on the shape memory property of PBAT.

The COVID-19 pandemic has caused severe challenges to ethnic minorities in the UK. While the experiences of migrants are both complex and varied depending on individuals' social class, race, cultural proximity to the host country and acculturation levels, more in-depth studies are necessary to fully understand how COVID-19 affects specific migrant groups and their health. Taiwanese migrants were selected because they are an understudied group. Also, there were widespread differences in pandemic management between the UK and Taiwan, making this group an ideal case for understanding how their acculturation journey can be disrupted by a crisis.

Qualitative data were collected at two different time points, at the start of the UK pandemic (March/April 2020) and six months on (October/November 2020), to explore migrant coping experiences over time. Theoretically, the authors apply acculturation theory through the lens of coping, while discussing health-consumption practices, as empirical evidence.

Before the outbreak of the pandemic, participants worked hard to achieve high levels of integration in the UK. The pandemic changed this; participants faced unexpected changes in the UK’s sociocultural structures. They were forced to exercise the layered and complex “coping with coping” in a hostile host environment that signalled their new marginalised status. They faced impossible choices, from catching a life-threatening disease to being seen as overly cautious. Such experience, over time, challenged their integration to the host country, resulting in a loss of faith in the UK’s health system, consequently increasing separation from the host culture and society.

It is important to note that the Taiwanese sample recruited through Facebook community groups is biased and has a high level of homogeneity. These participants were well-integrated, middle-class migrants who were highly educated, relatively resourceful and active on social media. More studies are needed to fully understand the impact on well-being and acculturation of migrants from different cultural, contextual and social backgrounds. This being the case, the authors can speculate that migrants with less resource are likely to have found the pandemic experience even more challenging. More studies are needed to fully understand migrant experience from different backgrounds.

Public health policymakers are advised to dedicate more resources to understand migrants' experiences in the host country. In particular, this paper has shown how separation, especially if embraced temporarily, is not necessarily a negative outcome to be corrected with specific policies. It can be strategically adopted by migrants as a way of defending their health and well-being from an increasingly hostile environment. Migrants' home country experience provides vicarious learning opportunities to acquire good practices. Their voices should be encouraged rather than in favour of a surprising orthodox and rather singular approach in the discussion of public health management.

The paper has clear public health policy implications. Firstly, public health policymakers are advised to dedicate more resources to understand migrants' experiences in the host country. Acknowledging migrants' voice is a critical first step to contribute to the development of a fair and inclusive society. Secondly, to retain skilful migrants and avoid a future brain-drain, policymakers are advised to advance existing infrastructure to provide more incentives to support and retain migrant talents in the post-pandemic recovery phase.

This paper reveals how a group of previously well-integrated migrants had to exercise “coping with coping” during the COVID crisis. This experience, over time, challenged their integration to the host country, resulting in a loss of faith in the UK’s health system, consequently increasing separation from the host culture and society. It contributes to the understanding of acculturation by showing how a such crisis can significantly disrupt migrants' acculturation journey, challenging them to re-acculturate and reconsider their identity stance. It shows how separation was indeed a good option for migrants for protecting their well-being from a newly hostile host environment.

We applied a true-experimental randomized control posttest design to collect and analyze quantitative and qualitative data to compare the effects of the AR and traditional board games on students’ SDG learning achievements.

We applied a true-experimental randomized control posttest design to collect and analyze quantitative and qualitative data to compare the effects of AR and traditional board games on students' SDG learning achievements.

Our analysis of the quantitative and qualitative data revealed that the effects of AR and traditional board games on the students' cognitive outcomes differed significantly, indicating the importance of providing a situated learning environment in SDG education. Moreover, the students perceived that the incorporation of the AR game into SDG learning improved their learning effectiveness – including both cognitive and affective dimensions – thus confirming its educational value and potential in SDG learning.

To the best of our knowledge, this is the first study to explore the effectiveness of different learning tools (AR and traditional board games) and to evaluate the importance of providing a situated learning environment through a true-experimental randomized control posttest design.

This study aims to research the influence mechanism of microtextured geometric parameters of dry gas seal end face on the tribological behavior under dry frictional conditions.

The microtexture was processed using laser processing, while the diamond-like carbon (DLC) film was applied through magnetron sputtering; the experimental platform of friction vibration was established, the frictional and vibrational properties of different geometric parameters were tested; the data signals of vibrational acceleration and frictional torque were collected and processed using data acquisition instrument. The entropy characteristic parameters of 3D vibrational acceleration were extracted based on wavelet packet decomposition method. The end-face topography was measured with ST400 three-dimensional noncontact surface topography instrument.

The geometry of pits plays a key role in influencing friction performance; the permutation entropy and fuzzy entropy of the vibration acceleration signal changed with variations in microtextured parameters. A textured surface with appropriately size parameters can trap debris, enhance the dynamic pressure effect, reduce impact between the friction interfaces and improve the frictional vibrational performance. In this research, microtextured surface with Φ150 µm-10% and Φ200 µm-5% can effectively reduce friction and vibration between the end faces of a dry gas seal.

DLC film improves the hardness of seal ring end face, and microtexture improves the dynamic effect; the tribological behavior monitoring can be realized by analyzing the characteristics of vibration acceleration sensitive parameter with friction state. The findings will provide a basis for further research in the field of tribology and the microtexture optimization of dry gas seal ring end face.

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2023-0389/

This study examines the effect of digitalization on poverty and income inequality in developing countries. The study answers the question of whether digitalization is a way for developing countries to get out of poverty and income inequality.

The study uses data from 17 developing countries with data from 2005 to 2021. The study employs fully modified ordinary least squares (FMOLS) and dynamic ordinary least squares (DOLS), with an augmented mean group (AMG) for robustness. Digitalization, as the variable of interest, is proxied by the digitalization index (DI), constructed using principal component analysis (PCA). The dependent variables are poverty and income inequality, which are used in different models.

The evidence indicates that digitalization decreases poverty and income inequality in developing countries. These findings are justified when we use the AMG estimator, but the strength of the coefficients and significance levels are higher in the FMOLS and DOLS estimators. The results of the control variables also show that human development (LHDI), CO2 emissions and foreign direct investment (FDI) have decreasing effects on poverty and income inequality. Thus, digitalization is a good option for developing countries to get out of poverty and income inequality to achieve sustainable development goals (1&10).

This study provides rigorous empirical evidence on the effect of digitalization on poverty and income inequality in developing countries. Unlike the previous studies on developing countries, this study used a DI to proxy digitalization. In addition, the authors use FMOLS and DOLS estimators, with an AMG estimator for robustness, to provide long-run coefficients.

The peer review history for this article is available at: https://publons.com/publon/10.1108/IJSE-08-2023-0586

The purpose of this paper is to investigate the efficacy of bacterial exopolysaccharides (Eps) in reactive black 5 (RB5) textile dye wastewater bioremediation.

The Eps were produced by bacteria isolated from cotton gin trash soils collected from different cotton-growing regions in Kenya for comparison purposes. A broth medium reconstituted using molasses was assessed for its capacity to produce the Eps. RB5 textile dye wastewater was optimized for dye removal under different temperatures, times and molasses concentrations. Dye removal was studied by Lovibond-Day Light Comparator, UV–Vis spectrophotometer and FTIR.

It was found that cotton gin trash soils contained Eps-producing bacteria. Three of the Eps studied were found to have the capacity to remove at least 80% of the dye from the wastewater.

This research did not assess the efficacy of the RB5 dye removal from the wastewater by mixtures of the Eps.

Bioremediation of textile dye wastewater with Eps produced by bacteria cultured from cotton gin trash soil is significant because it will offer an effective and cleaner alternative to the chemical coagulants.

Alternative treatment of textile wastewater with the Eps would result in safer water being released into the water bodies as opposed to the chemically treated wastewater that contains remnant chemicals.

Research on the use of Eps produced by bacteria isolated from cotton gin trash soils for removal of RB5 dye from textile wastewater has not been done before.