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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.

The purpose of this paper is to form a numerical simulation method for permeability coefficient that can consider the characteristics of gravel gradation and further explore the effects of indoor test factors and gradation characteristics on the permeability coefficient of gravel.

The random point method is used to establish the polyhedral gravel particle model, the discrete element method (DEM) is used to construct the gravel permeability test sample with gradation characteristics and the finite element method is used to calculate the permeability coefficient to form a DEM-computational fluid dynamics combined method to simulate the gravel seepage characteristics. Then, verified by the indoor test results. Based on this method, the influence of sample size, treatment method of oversize particles and the content of fine particles on the permeability coefficient of gravel is studied.

For the gravel containing large particles, the larger size permeameter should be used as far as possible. When the permeameter size is limited, the equal weight substitution method is recommended for the treatment method of oversized particles. Compared with the porosity, the pore connectivity has a higher correlation with the permeability coefficient of the sample.

Insufficient consideration of the movement of gravel particles in the seepage process is also an issue for further study.

The simulation method described in this paper is helpful for qualitative analysis, quantitative expression of pore size and makes up for the defect that the seepage characteristics in pores cannot be observed in laboratory tests.

This study aims to document the emotions experienced by women achieving high levels of organizational success and investigate what differences, if any, existed between C-Suite women in the West* and China** in this regard.

In total, 105 senior female leaders in Mainland China and the West participated in an in-depth electronic survey about their leadership journeys.

The emotional associations with the pathway to high-level positions were generally positive with gratitude, hope, excitement and pride standing out, but Western female leaders were significantly more likely to express fear and feeling overwhelmed than their counterparts, whereas significantly more Chinese female leaders reported feeling inadequate than the Western women. The Chinese sample reported directionally more positive emotions than Western ones. The Chinese women cited curiosity, joy and relief, but Western female leaders made no mention of these emotions in their leadership journeys.

Little has been published on the emotions that women experience on their way to very high-level positions. Many of these studies used other people’s perceptions of female leaders to understand their reactions to the biases and challenges facing them. This study elicited direct responses from female organizational leaders. Research comparing the journeys of Western and Chinese C-Suite women is limited. These results can be useful for educators and human resource professionals in supporting female career advancement in Mainland China and the West.

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 study aimed to compare the performance of sustainable shoes made with bacterial cellulosic composite and commercial leather shoes using an experimental research design. The two specific research objectives were: (1) to examine the basic material properties of multi-layered bacterial cellulosic materials (MBC), which include green tea-based cellulosic (GBC) mats, hemp fabrics, and denim fabrics, in comparison with those of two-layered leathers (MCP) consisting of calf-skin and pig-skin – commonly used in shoe manufacturing; and (2) to explore wearers’ performance in the two types of shoes by assessing quantitative kinematic and kinetic parameters of lower body movements.

This study focused on assessing the basic materials testing and performance of sustainable shoes through a biomechanical approach, in contrast to commercially available leather shoes, through human wear trials. In this study, green tea-based cellulosic (GBC) mats were developed using the optimal combination of ingredients for cellulose growth. Subsequently, the GBC, denim fabric (100% cotton), and 100% hemp fabric were combined to create multi-layered bacterial cellulosic materials (MBC) as an alternative to leather. Additionally, calf-skin and pig-skin leathers were utilized to produce a commercially available two-layered leather (MCP), commonly employed in shoe manufacturing. 37 of the 42 human subjects who participated in wear testing were collected. A paired t-test was conducted to determine whether significant mean differences existed between the two shoe types, a paired t-test was conducted.

To develop a biodegradable and compostable material that could be used as a leather alternative for the footwear industry, we proposed MBC and examined its properties compared with those of MCP, a product often used when making shoes. These findings confirmed the similar properties of MBC and MCP from the material testing and the possibility of using a men’s sustainable shoe prototype as a leather alternative, in terms of kinematics and kinetics.

The new multi-layered bacterial cellulosic materials (MBC) could be an alternative to commercial leathers such as innovative sustainable material construction, advanced design, and advanced techniques to optimize the overall performance of sustainable footwear.

Investigating the integration of smart textile technologies, ergonomic design principles, and personalized customization will contribute to developing MBC and making sustainable shoes using MBC compared with commercial leather shoes. This study provides valuable insights into further refinement and innovation in the sustainable footwear industry.

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.

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.

Airbnb attempts to stimulate consumer imagination and expectations of home through storytelling before their stay. The purpose of this study is to gain a holistic understanding of the psychological mechanisms by which brand storytelling can evoke consumer imagination of home away from home and their choice of peer-to-peer (P2P) accommodations.

By collecting 864 valid questionnaires through two rounds of surveys with Chinese consumers, this study examined the structural relations between narrative elements in the brand story (home characteristics, social interactions in advertising, advertising features), brand perception, self-image congruence and consumption intentions.

The results demonstrate that home characteristics, social interactions in advertising, and advertising features positively influence people’s brand perceptions, self-image congruence and consumption intentions through mental imagery processing.

This study offers helpful implications on how to create a home feeling in P2P accommodations and provides recommendations to promote the connection between consumers and the brand for P2P accommodation providers and hoteliers.

This study reveals the underlying mechanism of how various narrative elements in brand stories inspire the imagination and feeling of home in consumers during the prestay phase. By analysing the impact of specific trust systems and emotional needs on the construction of a feeling of home, this study is an important complement to existing studies on the study of home in P2P accommodation.

Low-carbon agricultural technology (LAT) extension is a key strategy for the agricultural sector to address climate change. Social capital, which consists of social networks, trust and norms, can play an active LAT extension role. This paper aims to analyze the mechanism of the role of social capital in the process of LAT extension.

Questionnaire data from six counties in Jiangsu, China, were used to measure social capital and analyze its effect on LAT extension using logistic regression. Data from 27 interviews were used to analyze the LAT extension experiences and problems.

LAT is mainly deployed by the government to farmers and distributed among them. In this process, the village officials who form parts of the government’s composition and the villagers play a dual role that facilitates a close link between them and the farmers and ensures LAT integration. However, social norms did not play a significant role in the process.

Farmers’ acceptance of LAT is based solely on the trade-off between local networks’ benefits and trust in local villagers and village officials. LAT-related laws and technical measures, thus are essential to strengthen LAT practices’ authority and incorporate LAT-based agricultural production as the norm of production behavior.

This paper provides an insight into the process and essence of farmers’ acceptance of LAT, which provides theoretical lessons for the LAT extension in China and indeed other developing countries.

Covid-19 cases are rising at a high rate in Thailand. Thailand’s administration has formulated many initiatives to combat the spread of coronavirus. However, during a pandemic, health-care workers have a diverse range of tasks that make it more challenging to continue working in hospitals. Consequently, the authors modeled the turnover intentions of health-care personnel to capture relevant psychological aspects of employees during the pandemic. Specifically, this study aims to focused on the moderating role of Covid-19 burnout (CBO) in the relationship between transformational leadership (TL) and job turnover intentions (JTI) with job satisfaction (JS) and knowledge hiding (KH) as mediators.

This research collected data using self-administered questionnaire. A two-stage partial least square–structural equation modeling (PLS-SEM) is carried out as an analysis technique to measure the linear relationship among constructs. The study tests hypotheses (direct and indirect effects) using 310 sample size of health-care personnel.

The findings indicated that CBO intensified the JTI of health-care personnel and strengthened the association of JS and KH with JTI during the Covid-19 pandemic. TL had a negative indirect effect on JTI. In addition, JS had a negative impact on JTI.

The study highlights the importance of TL and JS as ways to reduce or alleviate JTI in health-care personnel during the Covid-19 pandemic in Thailand. Furthermore, CBO and KH can enhance JTI in health-care personnel.