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The purpose of this paper is to investigate the oscillating trajectory of the paddle of a fin-wheel underwater robot to enhance its propulsion efficiency in water. This robot can be used for underwater detection and military operations.

By studying the propulsion mode of underwater fin-based robots, it is found that such robots periodically generate a large reverse thrust during the swing process, resulting in low propulsion efficiency. Therefore, according to the propulsion characteristics of the oscillating paddle in the underwater environment, the hydrodynamic model and physical constraints of the oscillating paddle are established. Then, the oscillating gait trajectory of the paddle is optimized by the trajectory optimization method. The performance of the optimized trajectory was tested in the simulation environment and the actual underwater environment.

The prototype of the robot was built and tested in a small swimming pool. The research results confirm that the propulsion efficiency of the optimized trajectory is higher than that of the traditional trajectory under the condition of the same amplitude and period. Specifically, the maximum speed of the robot can reach 0.24 m/s when using the optimized trajectory, which is about 50% higher than that before optimization.

The optimized trajectory with the generated impulse as the optimization target is applied to the paddle oscillation, which can improve the thrust impulse generated by the fin-wheel underwater robot during underwater motion, thereby greatly improving the underwater propulsion efficiency and moving speed.

Drawing upon psychological ownership theory, the aim of this study was to uncover the coexisting mediating effects of knowledge sharing and hiding on the relationship between employees’ organizational psychological ownership (OPO) and their innovative work behavior (IWB). The moderating role of organizational context in these mediating relationships was further examined to determine the moderated mediation paths.

This study mainly used a survey-based research method and collected data from 512 professionals from both public and private organizations in Pakistan to test our proposed hypotheses.

The results showed that coexisting knowledge sharing and hiding mediated the relationship between employees’ OPO and IWB. Furthermore, organizational context moderated the mediated relationships, providing support for the moderated mediation framework.

The results highlight the significance of fostering employees’ OPO to enhance their IWB by promoting knowledge sharing and preventing knowledge hiding. This study also urges managers to consider the contingency effect of organizational contexts when promoting employees’ IWB in emerging economies.

The results obtained in this study suggest that the knowledge behavior paradox occurs in organizations, and distinct organizational contexts play crucial but differential roles in intervening in the effect of employees’ OPO on their IWB. This study empirically validated this complex mechanism in an important emerging economy in Asia.

This paper aims to investigate the corrosion kinetics and corrosion behavior of NdFeB magnets with the addition of heavy rare earth dysprosium (Dy) for its inhibitory activity on poor corrosion resistance of NdFeB magnets.

To study the effect of dysprosium addition on corrosion behavior of NdFeB magnets and investigate its mechanism, potentiodynamic polarization, scanning electron microscopy (SEM), electrochemical impedance, energy dispersion spectrum (EDS) and scanning Kelvin probe force microscopy (SKPFM) were applied in the research. Besides, microstructures were observed by SEM equipped with EDS. Atomic force microscopy was introduced to analyze the morphology, potential image as well as the contact potential difference. The SKPFM mapping scan was applied to obtain the contact potential around Nd-rich phase at 0.1 Hz. The magnets were detected via X-ray diffraction.

Substitution of Nd with Dy led to improvement of corrosion resistance and reduced the potential difference between matrix and Nd-rich phase. Corrosion resistance is Nd-rich phase < the void < metal matrix; maximum potential difference between matrix and Nd-rich phase of Dy = 0, Dy = 3 and Dy = 6 Wt.% is 411.3, 279.4 and 255.8 mV, respectively. The corrosion rate of NdFeB magnet with 6 Wt.% Dy is about 67% of that without Dy at steady corrosion stage. The addition of Dy markedly enhanced the corrosion resistance of NdFeB magnets.

This research innovatively investigates the effect of adding heavy rare earth Dy to NdFeB permanent magnets on magnetic properties, as well as their effects on microstructure, phase structure and most importantly on corrosion resistance. Most scholars are studying the effect of element addition on magnetic properties but not on corrosion resistance. This paper creatively fills this research gap. NdFeB magnets are applied in smart cars, robotics, AI intelligence, etc. The in-depth research on corrosion resistance by adding heavy rare earths has made significant and outstanding contributions to promoting the rapid development of the rare earth industry.

The purpose of this study is to enrich the literature on employee relations with a new model focusing on the effect of institutional structure and that of employees’ organizational identification on the relationship between institutional structure in an organization and employees’ pro-environmental behaviors, which represents an alternative approach for understanding employees’ pro-environmental performance.

We collect multi-level and multi-source data from 52 four- or five-star hotels in China (N = 963). For data analysis, we adopt the approach of multilevel structural equation modeling.

The results suggest that organizations’ green institutional structure (G-structure) can significantly influence employees’ organizational identification, which in turn can increase their pro-environmental performance.

We propose a new multi-level theoretical perspective to explain employees’ pro-environmental behaviors. While prior studies on the issue mainly consider only the effects of such micro-level variables as ability, motivation and personality, we focus on the effect of organizational institution and its interaction with micro-level variables so that we can evaluate the effect a commonly-studied contextual variable, i.e. green institutions, on the behaviors. Moreover, in this new theoretical model, we also take into account the effect of another insufficiently-tested micro-level variable, i.e. employees’ identification, which has not been considered as frequently as other micro-level variables in studying employees’ pro-environmental performance. Our results highlight the importance of all these variables and suggest a valuable alternative model for more comprehensive research of employees’ green performance.

In the era of the digital economy, higher demands are placed on versatile talents, and the cultivation of students with innovative and entrepreneurial abilities has become an important issue for the further development of higher education, thus leading to extensive and in-depth research by many scholars. The study summarizes the characteristics and patterns of dual-innovation education at different stages of development, hoping to provide a systematic model for the development of dual-innovation education in China and make up for the shortcomings.

This paper uses Citespace software to visualize and analyze the relevant literature in CNKI and Web of Science databases from a bibliometric perspective, focusing on quantitative analysis in terms of article trends, topic clustering, keyword co-linear networks and topic time evolution, etc., to summarize and sort out the development of innovation and entrepreneurship education research at home and abroad.

The study found that the external characteristics of the literature published in the field of bi-innovation education in China and abroad are slightly different, mainly in that foreign publishers are more closely connected and have formed a more stable ecosystem. In terms of research hotspots, China is still in a critical period of reforming its curriculum and teaching model, and research on the integration of specialization and creative education is in full swing, while foreign countries focus more on the cultivation of students' entrepreneurial awareness and the enhancement of individual effectiveness. In terms of cutting-edge analysis, the main research directions in China are “creative education”, “new engineering”, “integration of industry and education” and “rural revitalization”.

Innovation and entrepreneurship education in China is still in its infancy, and most of the studies lack an overall overview and comparison of foreign studies. Based on the econometric analysis of domestic and foreign literature, this paper proposes a path for domestic innovation and entrepreneurship education reform that can make China's future education reform more effective.

The purpose of this paper is to investigate the effect of internal control (IC) on earnings quality from the perspective of the capital market. Specifically, it examines the effect of IC on earnings response coefficients.

This study uses the moderated regression analysis on a sample of 1,310 Chinese listed firms on the Shanghai Stock Exchange (SSE) from 2020 to 2022. It employed an earnings response coefficient model by Holthausen and Verrecchia (1988) and used the IC score produced by the index created by the Shenzhen Dibo Enterprise Risk Management Technology, i.e. DIB IC, and risk management database.

The study finds that the capital market placed lower earnings reliability on companies with high IC. This suggests that investors perceived negatively on the IC score of China listed companies, possibly due to their negative perception on the reason for implementation of high IC by those companies. A high IC score may raise suspicion amongst investors that the company has internal issues.

This study adds to the limited studies on less regulated internal governance mechanisms from the perspective of the capital market. The contradictory result suggests the need for more studies before deriving a solid conclusion.

This study focusses on the under research area of IC rather than the common board of directors and from the perspective of Chinese economies, limited studies of developed countries.

Despite their significant economic impact, small and medium-sized enterprises (SMEs) remain underrepresented in public procurement. While previous research has identified the barriers facing SMEs in public procurement markets, a knowledge gap still exists on how these barriers influence one another in a specific context.

This study developed a hierarchical structural model that reveals the contextual interrelationships between 14 notable barriers to SME involvement in public procurement, based on evidence from the publicly funded healthcare sector in the UK. The data were analyzed using interpretive structural modeling (ISM) and matrix impact of cross-multiplication applied to categorization (MICMAC).

The results systematically classify barriers based on their hierarchical relationships, offering a robust theoretical foundation for understanding their nature and interconnections.

The findings can help scholars, government administrators and politicians in government-funded healthcare systems determine the most influential barriers to SME involvement and their causes, enabling them to build viable remedies.

This is the first empirical study to examine the relationship between the barriers to SMEs' public health procurement, using evidence from the public health procurement context.

This study examines the impact of corporate social responsibility (CSR) on innovation, considering the role of the three dimensions of intellectual capital (human capital, structural capital and relational capital). Specifically, the analysis explores the direct effect of CSR and intellectual capital on innovation, the effect of CSR on intellectual capital, and the mediating effect of intellectual capital on the relationship between CSR and innovation.

Data were collected from a sample of 101 Tunisian firms operating in various industries. The conceptual model of direct and indirect effects was tested with partial least squares structural equation modelling (PLS-SEM) using SmartPLS 4 software.

CSR is positively related to innovation, as well as all dimensions of intellectual capital. Structural capital is the only dimension of intellectual capital that has a significant effect on innovation. CSR affects innovation through its impact on structural capital.

Most studies have examined the direct effect of CSR on innovation in firms in developed countries. In contrast, this research sheds light on the mediating role of intellectual capital in this relationship, underlining the specific role of human capital, relational capital and structural capital. In addition, the study focuses on a developing country, which thus differentiates it from previous studies.

The study aims to examine the impact of cultural dependency stemming from exchange rate fluctuations (specifically the US dollar) on herding behavior in the housing market across 31 provinces of Iran from Q2 2011 to Q1 2022, using a spatial econometrics approach. After confirming the presence of spatial effects, the Dynamic Spatial Durbin Panel Model with Generalized Common Effects (SDM-DPD(GCE)) was selected from various spatial models for these provinces.

The study examines the impact of cultural dependency stemming from exchange rate fluctuations (specifically the US dollar) on herding behavior in the housing market across 31 provinces of Iran from Q2 2011 to Q1 2022, using a spatial econometrics approach. After confirming the presence of spatial effects, the Dynamic Spatial Durbin Panel Model with Generalized Common Effects (SDM-DPD(GCE)) was selected from various spatial models for these provinces.

The model estimation results indicate that fluctuations in the free market exchange rate of the dollar significantly and positively impact the housing market in both target and neighboring regions, fostering herding behavior characterized by cultural dependency within the specified timeframe. Additionally, the study found that variables such as the inflation rate, population density index and the logarithm of stock market trading volume have significant and positive impacts on the housing market. Conversely, the variable representing the logarithm of the distance from the provincial capital, Tehran, significantly and negatively impacts the housing market across Iranian provinces.

Given that housing is a fundamental need for households, the dramatic price increases in this sector (for instance, a more than 42-fold increase from 2011–2021) have significantly impacted the welfare of Iranian families. Currently, considering the average housing price in Tehran is around 50 million Tomans, and the average income of worker and employee groups is 8 million Tomans (as of 2021), the time required to purchase a 100-square-meter house, even with a 30% savings rate and stable housing prices, is approximately 180 years. Moreover, the share of housing and rent expenses in household budgets now constitutes about 70%. The speculative behavior in this market is so acute that, despite 25 million of Iran’s 87 million population being homeless or renting, over 2.5 million vacant homes (12% of the total housing stock) are not used. Therefore, various financial behaviors and decisions affect Iran’s housing market. Herd behavior is triggered by the signal of national currency devaluation (with currency exchange rates increasing more than 26-fold between 2011 and 2021) and transactions at higher prices in certain areas (particularly in northern Tehran) (Statistical Center of Iran, 2023). Given the origins of housing price surges, a price increase in one area quickly spreads to other regions, resulting in herd behavior in those areas (spillover effect). Consequently, housing market spikes in Iran tend to follow episodes of currency devaluation. Therefore, considering the presented discussions, one might question whether factors other than economic ones (such as herd behavior influenced by dependence culture) play a role in the rising housing prices. Or, if behavioral factors were indeed contributing to the increase in housing prices, what could be the cause of this herd movement? Has the exchange rate, particularly fluctuations in the free market dollar rate, triggered herd behavior in the housing market across Iran’s provinces? Or has the proximity and neighborhood effect been influential in the increase or decrease in housing prices in the market?

Compared to quad-rotor unmanned aerial vehicle (UAV), the tilting dual-rotor UAV is more prone to instability during exercises and disturbances. The purpose of this paper is using an active balance tail to enhance the hovering stability and motion smoothness of tilting dual-rotor UAV.

A balance tail is proposed and integrated into the tilting dual-rotor UAV to enhance hovering stability and motion smoothness. By strategically moving, the balance tail generates additional force and moment, which can promote the rapid stability of the UAV. Subsequently, the control strategy of the UAV is designed, and the influence of the swing of the balance tail at different installation positions with different masses on the dual-rotor UAV is analyzed through simulation. The accompany motion law and the active control, which is based on cascade Proportion Integration Differentiation (PID) control to enhance the hovering stability and motion smoothness of the UAV, are proposed.

The results demonstrate that active control has obvious adjustment effectiveness when the UAV moves to the target position or makes an emergency stop compared with the results of balance tail no swing and accompany motion.

The balance tail offers a straightforward means to enhance the motion smoothness of tilting dual-rotor UAV, rendering it safer and more reliable for practical applications.

The novelty of this works comes from the application of an active balance tail to improve the stability and motion smoothness of dual-rotor UAV.