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The focus of the current research is to examine whether mixed-frequency investor sentiment affects stock volatility in the China A-shares stock market.

Mixed-frequency sampling models are employed to find the relationship between stock market volatility and mixed-frequency investor sentiment. Principal analysis and MIDAS-GARCH model are used to calibrate the impact of investor sentiment on the large-horizon components of volatility of Shanghai composite stocks.

The results show that the volatility in Chinese stock market is positively influenced by B–W investor sentiment index, when the sentiment index encompasses weighted mixed frequencies with different horizons. In particular, the impact of mixed-frequency investor sentiment is most significantly on the large-horizon components of volatility. Moreover, it is demonstrated that mixed-frequency sampling model has better explanatory powers than exogenous regression models when accounting for the relationship between investor sentiment and stock volatility.

Given the various unique features of Chinese stock market and its importance as the major representative of world emerging markets, the findings of the current paper are of particularly scholarly and practical significance by shedding lights to the applicableness GARCH-MIDAS in the focused frontiers.

A more accurate and insightful understanding of volatility has always been one of the core scholarly pursuits since the influential structural time series modeling of Engle (1982) and the seminal work of Engle and Rangel (2008) attempting to accommodate macroeconomic factors into volatility models. However, the studies in this regard are so far relatively scarce with mixed conclusions. The current study fills such gaps with improved MIDAS-GARCH approach and new evidence from Shanghai A-share market.

When considering the influence of external social, technical and political environments on organizations’ open innovation behavior, especially in emerging markets, institutional theory is especially salient. This study aims to answer the question of how to integrate organizations’ external institutional pressures and internal knowledge structure to mitigate the challenges in the open innovation process.

This study uses a sample of 2,126 observations from the 2012 World Bank Enterprise Survey. A multivariate regression model is designed to explore the impact of external institutional pressure (i.e. coercive pressure, mimetic pressure and normative pressure) on open innovation, as well as the moderating effect of digital knowledge and experience-based knowledge.

The results show that institutional pressure has a positive role in promoting open innovation; digital knowledge weakens the positive relationship between institutional pressure and open innovation; experience-based knowledge strengthens the positive relationship between institutional pressure (especially coercive pressure) and open innovation.

This study combines institutional theory and knowledge management to enriches insights into open innovation in emerging markets. Beyond recognizing the inherent multidimensionality of the concept of institutional pressure, this study creates an integrated path for the legitimacy acquiring of enterprises through the knowledge structure design (i.e. digital knowledge and experience-based knowledge). It also deepens the institutional pressure to enable the implementation of digital knowledge to manage open innovation processes.

The communication link in the engineering of Internet of Vehicle (IOV) is more frequent than the communication link in the Mobile ad hoc Network (MANET). Therefore, the highly dynamic network routing reliability problem is a research hotspot to be solved.

The graph theory is used to model the MANET communication diagram on the highway and propose a new reliable routing method for internet of vehicles based on graph theory.

The expanded graph theory can help capture the evolution characteristics of the network topology and predetermine the reliable route to promote quality of service (QoS) in the routing process. The program can find the most reliable route from source to the destination from the MANET graph theory.

The good performance of the proposed method is verified and compared with the related algorithms of the literature.

In recent years, the airline industry has been growing and transforming rapidly in the Asia-Pacific area. This study analyzes and benchmarks the comparative operational efficiencies of the major Asian air carriers. Data envelopment analysis model and disaggregate output efficiency measures are used to evaluate the operational efficiencies of 31 Asian airlines from 2015 to 2019. The findings suggest that nonflag carriers, low-cost carriers, and high-income regions' carriers have significantly higher levels of efficiency than flag carriers, full-service carriers, and low-income regions' carriers in overall, revenue, and passenger traffic efficiencies. The efficiencies between alliance carriers and nonalliance carriers along with those of ASEAN and non-ASEAN carriers are not significantly different.

The purpose of this paper is to investigate the effect of urea–formaldehyde (UF) nanoparticles on the barrier property and delamination resistance for epoxy coating in a 3.5% NaCl aqueous solution.

The UF resin was synthesized via sol–gel method, and UF/epoxy composite coating was prepared through ball-milling process; the microstructure and chemical composition of UF resin were observed using the Fourier transform infrared spectroscopy, scanning electron microscopy and transmission electron microscopy; the bonding strength of coating/metal interface was investigated through adhesion test; the mechanical properties of the coatings were studied by tensile tests; and the barrier and corrosion resistance properties were verified using salt spray test, cathodic delamination test and electrochemical impedance spectroscopy measurements.

The experimental results indicated that the UF resin presented uniformly dispersed nanoparticles in the epoxy matrix and enhanced the bonding strength of coating/metal interface and then improved the delamination resistance for composite coating, which resulted in the enhancement of the barrier property and corrosion resistance for UF/epoxy composite coating.

In this paper, an easily prepared blending compounding coating with excellent corrosion resistance property was synthesized via sol–gel method and ball-milling process. The effects of UF nanoparticles on the barrier property and delamination resistance were investigated in detail.

This study investigates the influence of COVID-19 on technical efficiency and Malmquist productivity for combo carriers, cargo-only carriers, and passenger-only carriers for the sample period 2006–2021. We employ the DEA model to derive rankings of relative technical efficiencies annually for each company type. The technical efficiency performance measure is then regressed on standard cost determinants and (company-type)-(COVID-19) interaction variables to further examine COVID-19's influence on efficiency performance by company type. Then, we use the technical efficiency rankings to derive Malmquist productivity measures for all three types of airline companies. We hypothesize that cargo-only companies were better suited to operate during the pandemic because initially compared to combo-carriers and passenger-only carriers, these cargo-only companies operated with greater capacity due to higher shipper demand. In support of this study's hypothesis, findings show (1) combo carriers and passenger-only carriers experienced a significant technical efficiency erosion during the early stages of COVID-19. In contrast, cargo-only carriers did not experience an erosion of technical efficiency. We attribute this technical efficiency difference arising because cargo companies were able to continue operating at capacity during COVID-19. (2) These technical efficiency results contributed to declining productivity for combo and passenger carriers during the first year of COVID-19. Nonetheless, these companies were able to maintain relatively high levels of technological change.

In the face of increasing resource insecurity, environmental degradation and climate change, more governments and businesses are now embracing the concept of the circular economy. This chapter presents some historical background to the concept, with particular attention paid to its assumed opposite, the ‘linear’ or growth economy. While the origins of the circular economy concept are to be found in 1960s environmentalism, the chapter draws attention to the influence of the then ‘new’ sciences of ecology and ‘cybernetics’ in shaping the public environmental discourse of the period. It also draws attention to the background of the present linear economy in postwar policies that encouraged reconstruction and a social and economic democratisation across the West, including an expansion of mass-consumption. It emphasises the role of the 1960s counterculture in generating a popular reaction against this expansionary growth-based agenda, and its influence in shaping subsequent environmentalism, including the ‘metabolic’ and ecological economic understanding of the environmental crisis that informs the concept of the circular economy. Reflecting upon this historical preamble, the chapter concludes that more attention should be paid to the economic, cultural and social contexts of consumption, now more clearly the main driver of our global environmental crisis. Without now engaging more directly with the ‘consumption problem’, the chapter argues, it seems unlikely that the goals of the circular economy can be met.

The discrepancy between the content of an article and its title is a key characteristic of fake news. Current methods for detecting fake news often ignore the significant difference in length between the content and its title. In addition, relying solely on textual discrepancies between the title and content to distinguish between real and fake news has proven ineffective. The purpose of this paper is to develop a new approach called semantic enhancement network with content–title discrepancy (SEN–CTD), which enhances the accuracy of fake news detection.

The SEN–CTD framework is composed of two primary modules: the SEN and the content–title comparison network (CTCN). The SEN is designed to enrich the representation of news titles by integrating external information and position information to capture the context. Meanwhile, the CTCN focuses on assessing the consistency between the content of news articles and their corresponding titles examining both emotional tones and semantic attributes.

The SEN–CTD model performs well on the GossipCop, PolitiFact and RealNews data sets, achieving accuracies of 80.28%, 86.88% and 84.96%, respectively. These results highlight its effectiveness in accurately detecting fake news across different types of content.

The SEN is specifically designed to improve the representation of extremely short texts, enhancing the depth and accuracy of analyses for brief content. The CTCN is tailored to examine the consistency between news titles and their corresponding content, ensuring a thorough comparative evaluation of both emotional and semantic discrepancies.

As a key basic component used in machining, high-speed steel (HSS) tools often prone to wear and failure during machining. Therefore, the purpose of this study is to adopt a suitable approach to improve the stability of the cutting force, the service life and the wear resistance.

Laser shock processing (LSP) was used to process the tool rake face and the tribological test was performed with ball-on-disk wear tester.

Experimental results show that cutting force of the LSP-treated tool is lower than untreated tool under the same cutting conditions. Wear rate of the tool nose treated by LSP decreases obviously and the tool life increases by 40 per cent.

HSS is often used in the manufacture of complex cutting tools. The main value of this article is to improve the tool surface wear resistance, thereby extending the service life of cutter. This paper is valuable not only in theory but also with reference value in engineering practice.

This chapter considers the productivity of 77 airlines between 1980 and 2013. We do so by estimating a stochastic frontier and decomposing the total factor productivity growth into efficiency, technical and scale efficiency change. Our results show that, on average, airlines increased productivity over the period but that, while efficiency and technical change improved, scale efficiency results indicate that the average airline moved away from the most productive scale size. This was especially so in the two decades after 1980. Comparisons between geographical areas, business models, networks and alliances are also made.