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This study aims to fabricate a novel electromagnetic interference (EMI) shielding composite aerogel with both thermal insulation and high temperature warning functions.

An emerging bio-based polypyrrole (PPy) gel/Fe₃O₄/calcium alginate (PFC) EMI shielding composite aerogel was prepared by freeze-drying and in situ polymerization method. First, Fe₃O₄/calcium alginate (CA) aerogel was obtained by freeze-drying the Fe₃O₄/CA mixture. Then, PPy/Fe₃O₄/CA was obtained by synthesizing PPy on the surface of CA/Fe₃O₄ aerogel through in situ polymerization. Finally, PPy/Fe₃O₄/CA was immersed in porphyrin solution (cross-linking agent) to get the final PFC EMI shielding composite aerogel.

Due to the matched impedance between Fe₃O₄ and PPy, the EMI shielding performance of PFC composite aerogel can reach up to −8 dB. In addition, the PFC EMI shielding composite aerogel also shows excellent self-extinguishing and thermal insulation properties. After leaving the flame, the burning PFC aerogel is quickly extinguished. When the PFC aerogel is placed on the heating plate at 230 °C, the temperature on the side of the aerogel away from the heating plate is only 90.3 °C after 5 min of heating. The electrical resistance of the PFC composite aerogel can be reduced from 3.62 × 104 O to 5 × 102 O to trigger the warning light after 3 s of exposure to the alcohol lamp flame. This reversible thermal resistance response characteristic can be used to give an early warning signal when the PFC encounters high temperature or flame.

This work provides a novel strategy for designing a multifunctional EMI shielding composite aerogel with repeatable high temperature warning performance. This PFC composite aerogel shows potential applications in the prevention of material combustion in high temperature electromagnetic environments.

The purpose of this paper is to explore and compare haze-related content between traditional and social media in China by applying agenda-setting theory and the extended parallel process model (EPPM). Specifically, this paper examines the correlation between the two forms of media in terms of the ranking of the attributes of haze (i.e. the EPPM components) and the interrelationships among the attributes.

Content analysis and semantic network analysis were employed to address the research aims.

The results revealed that more than half of the total messages on both types of media reflected the EPPM components, either threat or efficacy information. However, the imbalance between the threat and efficacy information was more prominent in the haze-related content presented in the People’s Daily than it was on Weibo. In addition, the results from a Spearman’s rank-order correlation and a quadratic assignment procedure (QAP) indicated that there was no significant correlation between the People’s Daily and Weibo in terms of the rankings of the attributes of haze (i.e. the EPPM components) or the interrelationships among the attributes.

This study is the first to apply a theoretical approach to examine and compare the nature of haze-related messages on traditional and social media.

This paper aims to propose a novel control scheme and offer a control parameter optimizer to achieve better automatic carrier landing. Carrier landing is a challenging work because of the severe sea conditions, high demand for accuracy and non-linearity and maneuvering coupling of the aircraft. Consequently, the automatic carrier landing system raises the need for a control scheme that combines high robustness, rapidity and accuracy. In addition, to exploit the capability of the proposed control scheme and alleviate the difficulty of manual parameter tuning, a control parameter optimizer is constructed.

A novel reference model is constructed by considering the desired state and the actual state as constrained generalized relative motion, which works as a virtual terminal spring-damper system. An improved particle swarm optimization algorithm with dynamic boundary adjustment and Pareto set analysis is introduced to optimize the control parameters.

The control parameter optimizer makes it efficient and effective to obtain well-tuned control parameters. Furthermore, the proposed control scheme with the optimized parameters can achieve safe carrier landings under various severe sea conditions.

The proposed control scheme shows stronger robustness, accuracy and rapidity than sliding-mode control and Proportion-integration-differentiation (PID). Also, the small number and efficiency of control parameters make this paper realize the first simultaneous optimization of all control parameters in the field of flight control.

This study aims to investigate the effects of environmental risk perception on the evaluation of socioeconomic development and subjective well-being in China.

A questionnaire survey was conducted, and data were collected from 408 participants of four major universities and government organizations in Changsha, China. Structural equation modeling (SEM) was used to analyze the collected data and to test the hypotheses with regard to the relationship among latent variables. Bayesian method was used as the statistical inference procedure.

Results show that environmental risk perception has a direct negative influence on perceived socioeconomic development and on subjective total well-being (i.e. both hedonic and eudaimonic well-being). The perceived socioeconomic development has a direct positive effect on the subjective total well-being; thus, it plays a partial mediation role between environmental risk perception and subjective total well-being.

Findings suggest that the environment protection act of the government and their contribution to socioeconomic development will significantly affect the total well-being of people. The empirical analysis is based on survey data; thus, this study may suffer the common problems of questionnaire survey.

Promoting pro-environment and health behaviors is important in developing a happy society.

This study demonstrates a significant negative effect of environmental risk perception on the total well-being of people according to SEM approach. This study determines two independent paths for government and policy makers to increase the total well-being of people in China, namely, increasing socioeconomic value to people and controlling and reducing environmental threats.

Very little or no study has explored the predictors of behaviour and traits that determine digital entrepreneurship (DE) success. In response, the purpose of this paper is to present a research model that takes information technology (IT) culture as a theoretical lens and personal innovativeness and experience in IT projects as theoretical constructs to predict behaviour and traits that explain DE success.

Based on the literature review, the authors propose hypotheses and a research model. The authors tested the model using structural equation modelling (SEM), by surveying a sample of digital entrepreneurs operating in the Yabacon Valley, Lagos, Nigeria.

The results indicate that IT culture is an essential predictor of achieving DE success. The results also suggest that an entrepreneur's innovativeness in IT and experience in IT projects have significant negative and positive moderating effects on the relationship between IT culture and achieving DE success.

This paper taps into a new setting – DE context – by exploring the moderation effects of an entrepreneur's innovativeness in IT and experience in IT projects on the link between their IT culture and achieving a successful DE outcome.

This model offers managers an understanding of how IT culture and personal innovativeness and experience in IT work together to achieve DE success. Meanwhile, it sheds some light on managers to treat individuals with different levels of experience differently.

The authors theorise IT culture, personal innovativeness and experience in IT and show their effects on DE success, thus making an essential contribution to the information systems (ISs) and entrepreneurship research and practice. Moreover, the authors provide a novel methodology to conceptualise IT culture as a second-order hierarchical reflective construct by giving evidence that partial least squares (PLS) path modelling can assess a hierarchical model with moderating effects. This study answers scholars' call to construct more accurate explanations of innovation outcomes in an increasingly digital world.

The present research study aims to explore the impact of the most recent Israeli–Palestinian conflict, which unfolded in October 2023, on global equity markets, including a wide range of both emerging and developed markets (as per the Morgan Stanley Capital Investment country classification).

The market model of event study methodology, with an estimation window of 200 days and 28-day event window (including event day, i.e. October 7, 2023), has been employed to investigate the event’s impact on the stock markets of different countries, with 24 emerging countries and 23 developed countries. The daily closing prices of the prominent indices of all 47 countries have been analyzed to examine the impact of the conflict on emerging markets, developed markets and overall global equity markets. Additionally, cross-sectional regression analysis has been performed to investigate the possible explanations for abnormal returns.

The findings of the study suggest the heterogeneous impact of the selected event on different markets. Notably, emerging markets and the overall global equity landscape exhibited substantial negative responses on the event day, as reflected in average abnormal returns of −0.47% and −0.397%, respectively. In contrast, developed markets displayed resilience, with no significant negative impact observed on the day of the event. A closer examination of individual countries revealed diverse reactions, with Poland, Egypt, Greece, Denmark and Portugal standing out for their positive or resilient market responses. Poland, in particular, demonstrated significantly positive cumulative abnormal returns (CARs) of 7.16% in the short-term and 8.59% in the long-term event windows (−7, +7 and −7, +20, respectively), emphasizing its robust performance amid the geopolitical turmoil. The study also found that, during various event windows, specific variables had a significant impact on the CARs.

The study suggests diversification and monitoring of geopolitical risks are key strategies for investors to enhance portfolio resilience during the Israeli–Palestinian conflict. This study identifies countries such as Poland, Egypt, Greece, Denmark and Portugal with positive or resilient market reactions, providing practical insights for strategic investment decisions. Key takeaways include identifying resilient markets, leveraging opportunistic strategies and navigating market dynamics during geopolitical uncertainties.

As per the authors’ thorough investigation and review of the literature, the present study is the earliest attempt to explore the short-term and long-term impact of the 2023 Israeli–Palestinian conflict on equity markets worldwide using the event study approach and cross-sectional regression analysis.

Building on social media and destination brand-related literature, this study aims to explore World Heritage Sites’ (WHSs) brand diffusion and formation process from long-term and short-term perspectives, which includes brand diffusion, user-generated content (UGC), opinion leaders and brand events’ impact.

This study uses a mixed-method including text mining, keyword analysis and social network analysis to explore the brand formation process of four popular WHSs in Beijing, namely, the Palace Museum, Great Wall, Summer Palace and Temple of Heaven and more than 10,000,000 users’ data on Sina Weibo has been implemented to uncover the underlying social media branding mechanism.

The results show that the number of postings keeps in a stable range in most months, but, in general, there are no common rules for changing trends among the four WHSs; long-term high-frequency keywords related to history and culture account for a higher percentage; different kinds of accounts have varying impacts on information diffusion, in which media accounts lead to a bigger influence. However, more followers do not necessarily mean more interactions and most of the interaction ratio is much lower than 0.01000; brand events facilitate brand dissemination and have an impact on the creation of UGC.

This study is valuable for destination marketers to deeper understand brand diffusion and formation and provides valuable insights for developing effective destination marketing strategies.

Unlike previous studies that only concern a few parts of destination brand formation via social media (e.g. brand diffusion, brand events or opinion leaders’ impact), this study takes a more comprehensive perspective by systematically analyzing the brand formation process of WHSs on social media. By considering both long-term diffusion and short-term representative events, this study provides a more holistic understanding of the branding mechanism.