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The purpose of this paper is to design a hybrid robust tracking controller based on an improved radial basis function artificial neural network (IRBFANN) and a novel extended-state observer for a quadrotor system with various model and parametric uncertainties and external disturbances to enhance the resiliency of the control system.

An IRBFANN is introduced as an adaptive compensator tool for model and parametric uncertainties in the control algorithm of non-singular rapid terminal sliding-mode control (NRTSMC). An exact-time extended state observer (ETESO) augmented with NRTSMC is designed to estimate the unknown exogenous disturbances and ensure fast states convergence while overcoming the singularity issue. The novelty of this work lies in the online updating of weight parameters of the RBFANN algorithm by using a new idea of incorporating an exponential sliding-mode effect, which makes a remarkable effort to make the control protocol adaptive to uncertain model parameters. A comparison of the proposed scheme with other conventional schemes shows its much better performance in the presence of parametric uncertainties and exogenous disturbances.

The investigated control strategy presents a robust adaptive law based on IRBFANN with a fast convergence rate and improved estimation accuracy via a novel ETESO.

To enhance the safety level and ensure stable flight operations by the quadrotor in the presence of high-order complex disturbances and uncertain environments, it is imperative to devise a robust control law.

A new idea of incorporating an exponential sliding-mode effect instead of conventional approaches in the algorithm of the RBFANN is used, which makes the control law resistant to model and parametric uncertainties. The ETESO provides rapid and accurate disturbance estimation results and updates the control law to overcome the performance degradation caused by the disturbances. Simulation results depict the effectiveness of the proposed control strategy.

This paper aims to design an adaptive nonlinear strategy capable of timely detection and reconstruction of faults in the attitude’s sensors of an autonomous aerial vehicle with greater accuracy concerning other conventional approaches in the literature.

The proposed scheme integrates a baseline nonlinear controller with an improved radial basis function neural network (IRBFNN) to detect different kinds of anomalies and failures that may occur in the attitude’s sensors of an autonomous aerial vehicle. An integral sliding mode concept is used as auto-tune weight update law in the IRBFNN instead of conventional weight update laws to optimize its learning capability without computational complexities. The simulations results and stability analysis validate the promising contributions of the suggested methodology over the other conventional approaches.

The performance of the proposed control algorithm is compared with the conventional radial basis function neural network (RBFNN), multi-layer perceptron neural network (MLPNN) and high gain observer (HGO) for a quadrotor vehicle suffering from various kinds of faults, e.g. abrupt, incipient and intermittent. From the simulation results obtained, it is found that the proposed algorithm’s performance in faults detection and estimation is relatively better than the rest of the methodologies.

For the improvement in the stability and safety of an autonomous aerial vehicle during flight operations, quick identification and reconstruction of attitude’s sensor faults and failures always play a crucial role. Efficient fault detection and estimation scheme are considered indispensable for an error-free and safe flight mission of an autonomous aerial vehicle.

The proposed scheme introduces RBFNN techniques to detect and estimate the quadrotor attitude’s sensor faults and failures efficiently. An integral sliding mode effect is used as the network’s backpropagation law to automatically modify its learning parameters accordingly, thereby speeding up the learning capabilities as compared to the conventional neural network backpropagation laws. Compared with the other investigated techniques, the proposed strategy achieve remarkable results in the detection and estimation of various faults.

As a distinctive form of communist heritage tourism, the ideology and government-led form of red tourism warrants an in-depth examination of how tourists consume and perceive it. This study aims to reveal tourists’ perception of red tourism through the lens of destination image.

This study collected 9,819 user-generated photographs within four types of red tourism destinations (RTDs) and used a computer visual and semiotic analysis approach to conduct photograph-based cognitive and affective attributes extraction. Network analysis further visualized the co-relations between cognitive images and affective images. ANOVA analysis compared the differences of the four types of destination images.

Ten dimensions of cognitive image and eight categories of affective image of red tourism were identified. It found that monuments, statues, memorial symbols were the distinctive cognitive features, and admiration was the most dominant emotion. Heterogeneity of destination images was identified among the four types of RTDs.

To the best of the authors’ knowledge, the study is one of the first to explore tourists’ consumption of red tourism through the lens of destination image, which reveals the inconsistencies between the officially projected images and tourists’ perceived images of red tourism. Using Plutchik’s model, it validates a series of positive and negative emotions contributing to the affective images of red tourism, which expands the findings of emotions within the extant red tourism research. Through combined applications of computer visual and semiotic analysis, ANOVA, network analysis and model visualization, the study provides an important methodological triangulation for photograph-based destination image studies.

红色旅游作为共产主义旅游的独特形式, 游客如何感知这种国家意识形态植入与政府主导型旅游值得深入研究。本研究旨在从目的地意象视角揭示游客红色旅游感知。

本研究收集四种类型的红色旅游地9819张用户生成照片, 利用计算机视觉-情感析法对照片进行认知和情感元素提取。复杂网络分析揭示了认知意象与情感意象之间的关联。方差分析比较了四种红色旅游地意象的差异。

本研究确定了红色旅游认知意象的十个维度和情感意象的八个类别。研究发现, 纪念碑、雕像、纪念符号是其独特的认知意象元素, 钦佩是其最主要的情感，四种类型红色旅游地意象存在差异性。

本文是同类研究中首次从目的地意象视角探索游客对红色旅游地感知, 揭示了红色旅游官方投射意象与游客感知意象之间的差异。利用Plutchik情感之轮模型, 验证了一系列积极和消极情绪构成红色旅游地情感意象, 拓展了红色旅游的情感发现。综合运用计算机视觉-情感分析、方差分析、网络分析和模型可视化等方法, 为基于照片的旅游目的地意象研究提供了一个重要方法。

Como forma distintiva del turismo del patrimonio comunista, la ideología y la forma gubernamental del turismo rojo justifican un examen en profundidad de cómo lo consumen y perciben los turistas. Este estudio pretende revelar la percepción que tienen los turistas del turismo rojo desde la perspectiva de la imagen del destino.

Este estudio recopiló 9.819 fotografías generadas por los usuarios dentro de cuatro tipos de destinos de turismo rojo, y utilizó un enfoque de análisis visual y semiótico por ordenador para llevar a cabo la extracción de atributos cognitivos y afectivos basados en fotografías. El análisis de redes visualizó además las correlaciones entre las imágenes cognitivas y las imágenes afectivas. El análisis ANOVA comparó las diferencias de los cuatro tipos de imágenes de destino.

Se identificaron diez dimensiones de imagen cognitiva y ocho categorías de imagen afectiva del turismo rojo. Se descubrió que los monumentos, las estatuas y los símbolos conmemorativos eran los rasgos cognitivos distintivos, y la admiración la emoción más dominante. Se identificó una heterogeneidad de imágenes de destino entre los cuatro tipos de destinos de turismo rojo.

El estudio es uno de los primeros en explorar el consumo de turismo rojo por parte de los turistas a través de la lente de la imagen del destino, lo que revela las incoherencias entre las imágenes proyectadas oficialmente y las imágenes percibidas por los turistas del turismo rojo. Utilizando el modelo de Plutchik, valida una serie de emociones positivas y negativas que contribuyen a las imágenes afectivas del turismo rojo, lo que amplía los hallazgos sobre las emociones dentro de la investigación existente sobre el turismo rojo. Mediante aplicaciones combinadas de análisis visual y semiótico por ordenador, ANOVA, análisis de redes y visualización de modelos, el estudio proporciona una importante triangulación metodológica para los estudios de la imagen del destino basados en fotografías.

A limited number of empirical studies have indicated that individuals who experience workplace ostracism tend to engage in subtle and retaliatory behaviors as a means of seeking inner peace. However, research on organizational behavior and employee psychology in relation to ostracism is still in its nascent stages. Specifically, further investigation is warranted to explore how supervisor ostracism influences task procrastination (TP) through psychological processes such as self-efficacy, self-esteem and motivation. Notably, a significant gap exists in the ostracism literature, as it has yet to thoroughly examine employee behaviors related to knowledge hiding (KH) and TP in the context of individual or team-based work (Zhao et al., 2016; Brouwer and Jansen, 2019). Therefore, the present study aims to address this gap and expand the research stream within the education sector by introducing “threat to self-esteem” (TSE) as a mediating factor in the outcomes of ostracism.

The study employed a quantitative approach, using questionnaires to collect data and mainly focused on statistics and standards. The authors used SPSS and Smart-PLS to employ numerical values developed from questionnaire surveys. Likewise, we employed primary data collection tools, including mixed survey analysis (self-reported and peer-reported). The data were collected from middle-level managers working in three public sector universities. By using a three-wave research design with a two-week interval in each phase, we were able to separate the measurement of the predictor and moderator factor [supervisor ostracism (SO) and individual resilience (IR)], mediator (TSE) and outcome variables (KH and TP).

The study has discovered a substantial relationship between variables, and all hypotheses are accepted according to the data results and findings. The study measures the effects of supervisor ostracism on knowledge hiding and task procrastination through mediating effect of threat to self-esteem, which individual resilience moderates. This study adds a few contributions to the current literature, following the goals stated above. First, this attempts to highlight employee KH behavior and TP behavior by identifying SO as the primary predictor.

The organization should closely monitor the level of workplace ostracism. One strategy to accomplish this goal is to routinely gauge the extent of ostracism at work using targeted techniques like surveys and observation. The organization can also create an employee assistance program for the workers to assist them in coping with the mistreatment and better adjusting to the workplace culture. Furthermore, employee empowerment and collaborative decision-making can boost workers' self-esteem, eventually leading to diminishing knowledge-hiding and procrastination habits inside the organization.

There is a research gap regarding the barriers to KH from the perspective of team dynamics and interpersonal mistreatment at work because prior research has focused on knowledge sharing, organizational culture and organizational obstruction. Research on organizational behavior and employee psychology in relation to ostracism is still in its nascent stages. Specifically, further investigation is warranted to explore how SO influences TP through psychological processes such as self-efficacy, self-esteem and motivation. Notably, a significant gap exists in the ostracism literature, as it has yet to thoroughly examine employee behaviors related to KH and TP in individual or team-based work.

This paper aims to explore factors influencing university students’ intent to take formal lectures completely through e-learning with cloud meetings.

This study has surveyed Chinese students who have experienced e-learning with cloud meetings as well as traditional massive open online courses (MOOC) without live dialogues. The data are analysed based on structural equation modelling to assess factors influencing students’ intent to choose e-learning with cloud meetings.

The findings show that as per the technology acceptance model, e-learning students who find learning to be easier with cloud meetings than MOOCs believe cloud meeting courses to be more beneficial and thus are more willing to take e-learning with cloud meetings.

This study compares e-learning with cloud meetings with MOOCs without live dialogues for the first time to highlight the value of open dialogues in real time for effective e-learning.

To improve the efficiency, accuracy and adaptivity of the parameter inversion analysis method of a rockfill dam, this study aims to establish an adaptive model based on a harmony search algorithm (HS) and a mixed multi-output relevance vector machine (MMRVM).

By introducing the mixed kernel function, the MMRVM can accurately simulate the nonlinear relationship between the material parameters and dam settlement. Therefore, the finite element method with time consumption can be replaced by the MMRVM. Because of its excellent global search capability, the HS is used to optimize the kernel parameters of the MMRVM and the material parameters of a rockfill dam.

Because the parameters of the HS and the variation range of the MMRVM parameters are relatively fixed, the HS-MMRVM can imbue the inversion analysis with adaptivity; the number of observation points required and the robustness of the HS-MMRVM are analyzed. An application example involving a concrete-faced rockfill dam shows that the HS-MMRVM exhibits high accuracy and high speed in the parameter inversion analysis of static and creep constitutive models.

The applicability of the HS-MMRVM in hydraulic engineering is proved in this paper, which should further validate in inversion problems of other fields.

An adaptive inversion analysis model is established to avoid the parameters of traditional methods that need to be set by humans, which strongly affect the inversion analysis results. By introducing the mixed kernel function, the MMRVM can accurately simulate the nonlinear relationship between the material parameters and dam settlement. To reduce the data dimensions and verify the model’s robustness, the number of observation points required for inversion analysis and the acceptable degree of noise are determined. The confidence interval is built to monitor dam settlement and provide the foundation for dam monitoring and reservoir operation management.

This study aims to study the effect of micro-groove texture geometric parameters on the lubrication characteristics of the tripod universal coupling.

The Navier–Stokes equation was used to analyse the influence of micro-groove geometric parameters on the coupling’s lubrication performance. Further, Kriging approximate model and neighborhood cultivation genetic algorithm (NCGA) were used to optimise the micro-groove geometric parameters and improve the coupling’s lubrication performance.

The results show that as the micro-groove depth and width increase, respectively, the oil film-bearing capacity first increases and then decreases; on the contrary, the friction coefficient first decreases and then increases. With the increase of the micro-groove inclination angle, the bearing capacity of the oil film first increases and then remains unchanged. At the same time, the friction coefficient first decreases and then increases slightly. The lubricating performance of the optimised coupling is significantly improved: the optimised oil film-bearing capacity increases by 12.5%, the friction coefficient reduces by 14% and the maximum oil film pressure increases by 4.3%.

At present, the grease lubrication performance of the micro-groove textured tripod universal coupling has not been studied. The micro-groove parameters are optimised, and the coupling’s lubrication performance is improved greatly by the Kriging model and NCGA algorithm. It is of great significance to extend the coupling’s fatigue life.

This paper aims to provide a valid insight into consumers' minds while considering word of mouth (WOM), brand image and uniqueness as independent variables while considering the tourism industry as the primary stakeholder.

The study adopts qualitative research methods and data collected from 1,033 respondents using convenience sampling methodology. The data are collected from different tourists spots in China and Pakistan. The PROCESS macro was utilized in this study using SPSS version 25.0 to inspect the impacts by using Model 4 and the conditional effects indirectly by utilizing Model 14.

Customer's intimacy, search for novel and unexplored destinations highlight WOM interactions and perceived service value. Service value, interactional justice and professional attitude of hotel management mediated all the given relationships significantly. The brand image does not mediate any significant associations. Perceived service value and brand image predict customer's loyalty, and WOM is the direct measure of their intentions, and these variables are market trend indicators. A tourist's response toward different destinations is described in this study with comparative analysis of Chinese and Pakistani tourists. The study results showed a significantly positive relationship between hotel management professional behavior, customer's loyalty, customer's intimacy and WOM.

The recruited population might not be represented as the broader and larger visitor population, resulting in restricting establishing tactics. Moreover, this study's results provide significant insight into a tourism industry, hence providing a chance to manage customer loyalty better.

This study contributes significantly to the body of knowledge and provides remarkable insight from the managerial perspective. Interactional justice results in significant value for hotel management directors and top management, front desk staff and operatives and front level employees and managers. Consumer sensitivity of fairness in interpersonal dealings calls for behavioral changes in frontline employees, especially those directly dealing with hotel visitors. Hotel staff and management should formulate a system to deal with the demands and needs of visitors. It should describe the rights and obligations of visitors and ensure that each customer is treated equally and with respect. Customers should be motivated to read the survey questionnaires kept in their rooms and offer their views on the services provided. This strategy might increase the customers' sense of empowerment and leading to notions of fairness in individual encounters.

This study provides an insight into the customer's minds while considering essential variables that include WOM, brand image, perceived service value and uniqueness.

One of the most critical and active research areas in the field of climate change in recent years has been the interaction between land use and carbon emissions (LUCE). As there is a lack of data to represent the knowledge structure and evolution of LUCE between 1987 and 2018, this paper turned to CiteSpace in order to identify and visualize the cited references and keyword networks, the distribution of categories and countries and highly cited references in connection to LUCE research. Two indicators, betweenness centrality (BC) and citation burst (CB) embedded in CiteSpace, were utilized to investigate the knowledge structures.

Two indicators, BC and CB embedded in CiteSpace, were introduced to investigate the knowledge structures.

Firstly, pre-2000 papers provide the main theoretical foundation for LUCE research, and the innovation of computer technology also provides new ideas and methods for related research. Secondly, greenhouse gas emissions from agriculture are attracting more attention. As agriculture also involves food security, the pressure on agriculture to reduce carbon is enormous, and more research and policy investment will be needed in the future. Thirdly, although the natural sciences ranked highly on BC detection, social and humanities sciences have contributed more to the LUCE research with an increasing emphasis on regional and global governance to combat climate change. Finally, keen interest in carbon emissions and sustainable development in developed countries, particularly in Europe, has led to a large number of LUCE studies. Research being done in developing countries that are most affected by climate change is also outstanding.

The results collected will assist scientific researchers to better understand the research status and frontier trends in this sector, thus permitting researchers to comprehend current research interests in the LUCE analysis field and providing useful information for further investigation and publication strategies.

China has recently introduced a new audit law that aims to increase the scope of audit supervision and raise the standards for preventing risks in auditing national public projects. This paper presents a systematic research study on the causes of audit risks in national public projects and discusses the process by which these causes contribute to the emergence of such risks. Furthermore, the paper investigates the core risk sources in various types of national construction project audit. This paper aims to provide theoretical support for auditors of national construction projects in risk avoidance when conducting audits.

In this study, the authors carefully selected five national public audit projects from China and performed a comprehensive analysis of 85 relevant audit documentation. The textual analysis was conducted using Nvivo12 software, and the grounded theory approach was adopted for generalization purposes.

Based on the research results, the findings suggest that there are five key causes contributing to the audit risk of national construction projects: professional competence, risk awareness, management capacity, level of attention and deliberate fraud. The most critical factor identified is management capability, with 59.93% of the data supporting this view. This conclusion was based on an analysis of state-owned enterprises, administrative organs and public institutions. Building upon this, a framework titled “the mechanism of audit risk factors with management capability as the core” was constructed.

This paper employs qualitative analysis methods to examine national construction projects in China, contributing new literature to the theoretical study of audit risk management. The article also provides practical recommendations for auditors on how to mitigate audit risks and improve the quality of audit services in national project governance.