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Cybersecurity competitions can effectively develop skills, but engaging a wide learner spectrum is challenging. This study aims to investigate the perceptions of cybersecurity competitions among Reddit users. These users constitute a substantial demographic of young individuals, often participating in communities oriented towards college students or cybersecurity enthusiasts. The authors specifically focus on novice learners who showed an interest in cybersecurity but have not participated in competitions. By understanding their views and concerns, the authors aim to devise strategies to encourage their continuous involvement in cybersecurity learning. The Reddit platform provides unique access to this significant demographic, contributing to enhancing and diversifying the cybersecurity workforce.

The authors propose to mine Reddit posts for information about learners’ attitudes, interests and experiences with cybersecurity competitions. To mine Reddit posts, the authors developed a text mining approach that integrates computational text mining and qualitative content analysis techniques, and the authors discussed the advantages of the integrated approach.

The authors' text mining approach was successful in extracting the major themes from the collected posts. The authors found that motivated learners would want to form a strategic way to facilitate their learning. In addition, hope and fear collide, which exposes the learners’ interests and challenges.

The authors discussed the findings to provide education and training experts with a thorough understanding of novice learners, allowing them to engage them in the cybersecurity industry.

This study aims to obtain methods to identify and find the place of damage, which is one of the topics that has always been discussed in structural engineering. The cost of repairing and rehabilitating massive bridges and buildings is very high, highlighting the need to monitor the structures continuously. One way to track the structure's health is to check the cracks in the concrete. Meanwhile, the current methods of concrete crack detection have complex and heavy calculations.

This paper presents a new lightweight architecture based on deep learning for crack classification in concrete structures. The proposed architecture was identified and classified in less time and with higher accuracy than other traditional and valid architectures in crack detection. This paper used a standard dataset to detect two-class and multi-class cracks.

Results show that two images were recognized with 99.53% accuracy based on the proposed method, and multi-class images were classified with 91% accuracy. The low execution time of the proposed architecture compared to other valid architectures in deep learning on the same hardware platform. The use of Adam's optimizer in this research had better performance than other optimizers.

This paper presents a framework based on a lightweight convolutional neural network for nondestructive monitoring of structural health to optimize the calculation costs and reduce execution time in processing.

This paper aims to investigate the impact of gender diversity in the composition of engagement auditors on the disclosure of key audit matters (KAMs) in a dual-signature environment.

The authors used the unique institutional setup of Taiwan, where the law requires that audit reports be signed by two audit partners. The authors examined the effect of gender diversity composition among engagement auditors on KAM disclosure, considering behavioral differences between female and male auditors.

The empirical results indicate that gender diversity composition in the dual-signature environment is associated with the number of disclosed KAM items (KAMIT) and the length of the explanations for each KAMIT. Furthermore, the authors found that gender diversity composition, particularly when led by female audit partners, has a more pronounced impact on the explanation of each KAMIT rather than on the disclosure of KAMIT. The authors also noted that the moderating effect of audit firm specialization does not influence the gender diversity composition of audit partners in disclosing KAMs.

This study’s empirical findings demonstrate that the interaction between different gender compositions in a dual-signature environment influences KAM disclosure.

The purpose of this paper is to analyze the impact of different information source on consumer attitudes toward genetically modified food.

The data used in this study are obtained from a large-scale nationwide consumers' survey in urban China conducted by the China Center for Agricultural Policy, Peking University, in 2020. A descriptive analysis between information sources and consumer attitudes toward GM food was conducted. Based on the collected data, an econometric model on the determinants of consumer attitudes was constructed and used for analysis.

This study shows that the impact of new media is currently no different than that of traditional media, indicating that the media campaign successfully reduced the spread of rumors and misinformation regarding GM food. Moreover, this study also shows that consumers whose main information source regarding GM foods is school hold more positive feelings toward such food.

This study contributes to the existing literature by examining the impact of information source on consumer attitudes toward GM food. To reverse consumers' negative attitudes, China has launched a widespread media campaign since the first decade of the 2000s. Results of this study show that authorities' efforts to manage and surveil new media have yielded the desired outcome.

Limited by the types of sensors, the state information available for musculoskeletal robots with highly redundant, nonlinear muscles is often incomplete, which makes the control face a bottleneck problem. The aim of this paper is to design a method to improve the motion performance of musculoskeletal robots in partially observable scenarios, and to leverage the ontology knowledge to enhance the algorithm’s adaptability to musculoskeletal robots that have undergone changes.

A memory and attention-based reinforcement learning method is proposed for musculoskeletal robots with prior knowledge of muscle synergies. First, to deal with partially observed states available to musculoskeletal robots, a memory and attention-based network architecture is proposed for inferring more sufficient and intrinsic states. Second, inspired by muscle synergy hypothesis in neuroscience, prior knowledge of a musculoskeletal robot’s muscle synergies is embedded in network structure and reward shaping.

Based on systematic validation, it is found that the proposed method demonstrates superiority over the traditional twin delayed deep deterministic policy gradients (TD3) algorithm. A musculoskeletal robot with highly redundant, nonlinear muscles is adopted to implement goal-directed tasks. In the case of 21-dimensional states, the learning efficiency and accuracy are significantly improved compared with the traditional TD3 algorithm; in the case of 13-dimensional states without velocities and information from the end effector, the traditional TD3 is unable to complete the reaching tasks, while the proposed method breaks through this bottleneck problem.

In this paper, a novel memory and attention-based reinforcement learning method with prior knowledge of muscle synergies is proposed for musculoskeletal robots to deal with partially observable scenarios. Compared with the existing methods, the proposed method effectively improves the performance. Furthermore, this paper promotes the fusion of neuroscience and robotics.

As to different angles of attack and nonlinear problems caused by high temperatures in coexisting hypersonic aircraft, people mainly rely on fluid software for research but lack analysis of flow mechanisms. Owing to computational difficulties, few people use numerical algorithms to combine them for discussion. Hence, this study aims to make a deep inquiry into the laminar flow and heat transfer of compressible Newtonian fluid in hypersonic aircraft with small attack angles.

In this paper, on the basis of mass, momentum and energy conservation laws, the governing equations of the hypersonic boundary layer are established. Viscosity, specific heat capacity and thermal conductivity are considered nonlinear functions concerning temperature. In virtue of the MacCormack finite difference method, the stationary numerical solutions are solved directly, and the validity of the algorithm is verified.

The results demonstrate that at Mach number 5, compared to the 0° attack angle, the maximum temperature near-wall at the 3° attack angle increases by about 25%. An enjoyable phenomenon is discovered, where the position corresponding to the maximum wall shear force shifts back as the attack angle and Mach number increase. The relationship between the near-wall maximum temperature versus attack angle and Mach number is fitted through numerical calculation results.

Empirical formulas can be used to estimate heat transfer characteristics at small attack angles, which will guide the design of aircraft thermal protection systems.

Modern subway transportation systems need to satisfy increasing safety demands to rapidly evacuate passengers under hazardous emergency circumstances, such as fires, accidents or terrorist attacks, to reduce passenger injuries or life losses. The emergency evacuation capacity (EEC) of a subway station needs to be revised timely, in case passenger demand increases or the evacuation route changes in the future. However, traditional ways of estimating EEC, e.g. fire drills are time- and resource-consuming and are difficult to revise from time to time. The purpose of this study is to establish an intuitive modelling approach to increase the EEC of subway stations in a stepwised manner.

This study develops an approach to combine agent-based evacuation modelling and building information modelling (BIM) technology to estimate the total evacuation time of a subway station.

Evacuation time can be saved (33% in the studied case) from iterative improvements including stopping escalators running against the evacuation flow and modifying the geometry around escalator exits. Such iterative improvements rely on integrating agent-based modelling and BIM.

The agent-based model can provide a more realistic simulation of intelligent individual movements under emergency circumstances and provides precise feedback on locations of evacuation bottlenecks. This study also examined the effectiveness of two rounds of stepwise improvements in terms of operation or design to increase the EEC of the station.

The purpose of this paper is to present the influence of inter-turn short circuit faults (ITSF) on electromagnetic vibration in high-voltage line-starting permanent magnet synchronous motor (HVLSPMSMS).

In this paper, the ampere–conductor wave model of HVLSPMSM after ITSF is established. Second, a mathematical model of the magnetic field after ITSF is established, and the influence law of the ITSF on the air-gap magnetic field is analyzed. Further, the mathematical expression of the electromagnetic force density is established based on the Maxwell tensor method. The impact of HVLSPMSM torque ripple frequency, radial electromagnetic force spatial–temporal distribution and rotor unbalanced magnetic tension force by ITSF is revealed. Finally, the electromagnetic–mechanical coupling model of HVLSPMSM is established, and the vibration spectra of the motor with different degrees of ITSF are solved by numerical calculation.

In this study, it is found that the 2np order flux density harmonics and (2 N + 1) p order electromagnetic forces are not generated when ITSF occurs in HVLSPMSM.

By analyzing the multi-harmonics of HVLSPMSM after ITSF, this paper provides a reliable method for troubleshooting from the perspective of vibration and torque fluctuation and rotor unbalanced electromagnetic force.

This study aims to conceptualize the dimensions of resilient leadership and develop the resilient leadership scale (RLS) through three studies.

In Study 1, based on interviews with 77 leaders and 8 junior employees, a seven-factor resilient leadership model was constructed. In Study 2, exploratory factor analysis (n = 237) was conducted to refine the initial items. In Study 3, confirmatory factor analysis (n = 610) was performed to validate the dimensional structure identified in Study 2, and different types of validity of the RLS were assessed.

The validated RLS composed of seven dimensions: contingency planning, improvisation, adaptive instructing, contingency control, emergency care, adjustment recovery and mutual growth. The scale showed desirable measurement qualities in terms of reliability and validity. Resilient leadership and its dimensions significantly impact employee turnover intentions and employee resilience.

This research contributes to the literature on the resilience of hospitality and tourism enterprises and enriches the research scope and theoretical framework of resilient leadership.

This research revealed the resilient leadership responses to crisis in hospitality and tourism enterprises with practical implications for tourism enterprise leaders to deal with major crisis.

Extensive macro- and micro-economics research has been conducted on China's tax reform, which replaced business tax with value-added tax (VAT). However, existing studies have not clarified the reform's impact on firm-level investment decisions. Hence, this study explored the effect of replacing business tax with VAT on firms' investment efficiency.

The study used 2010–2018 data from China's A-share listed companies and a difference-in-differences (DID) model to explore the effect of the reform on firm-level investment decisions.

The authors found that China's tax reform has improved investment efficiency in underinvested firms, increased liquidity and decreased the level of reliance on external financing. The tax reform had a greater effect on investment efficiency in firms with lower liquidity and higher external financing reliance. Its effect was also more significant among non-state-owned and small companies.

This study fills the aforementioned research gap by exploring the effects of China's tax reform, thus providing a theoretical reference and a basis for policymaking.