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This paper aims to prepare Poly(Styrene-Butyl acrylate-Methacrylic acid) @Poly Gallic acid-Fe³⁺ photonic crystal composite inks [P(St-BA-MAA)@PGA-Fe³⁺ PCCI, @ means the PGA-Fe³⁺ is loaded on the microspheres] and construct noniridescent structural colors on fabric substrates, with the goal of improving the visibility of structural colors.

P(St-BA-MAA)@PGA-Fe³⁺ PCCI were prepared by coating P(St-BA-MAA) microspheres with a metal-polyphenol network formed by gallic acid (GA, C₇H₆O₅) and Fe³⁺. The assembly effects of the inks were explored under different conditions, including pH, temperature, concentration and surface tension. The optimal self-assembly conditions of the inks were determined using the controlled variable method.

The results demonstrated the successful preparation of P(St-BA-MAA)@PGA-Fe³⁺ PCCI. The metal polyphenol network film composed of GA and Fe³⁺ was successfully coated on the surface of P(St-BA-MAA) seed microspheres. The assembly mechanism of the inks was investigated, indicating that at a diethylene glycol (DEG, C₄H₁₀O₃) concentration of 0.3 wt% and pH of 7, bright noniridescent structural colors could be formed on fabric surfaces after self-assembly by PCCI at 60 °C for 10 min. Furthermore, the mechanical fastness of the structural colors was enhanced due to the adherence of the soft shell composed of P(St-BA-MAA) and GA.

Utilizing a cost-effective approach and a diverse array of readily available raw materials, we have successfully prepared P(St-BA-MAA)@PGA-Fe³⁺ PCCI, which boasts superior performance and offers fabrics a range of unique coloring styles. This innovation paves the way for potential applications of structural colors in practical production, thereby broadening their realm of utility.

Due to rapid development, historic city areas are faced with urbanization damage to their characteristic urban identity besides physical deterioration and economic decay. The purpose of this paper is to address the following questions: What are the constituent elements of locality for historic areas? How does one classify historic areas according to locality elements? What are the characteristics of each kind of historic area? How does one identify to-be-protected locality elements according to different historic areas to realize sustainable development?

As a historic cultural city with a building history of over 3,000 years, Beijing has a myriad of distinctive historic areas, of which 367 were selected as the research samples. This paper classifies historic areas into the following four categories: distinctive areas, permanent areas, adaptive areas and inherited areas by analyzing the locality elements of 8,905 geo-tagged photos related to Beijing historic areas. The correlation among locality elements – the basis for joint protection – is also examined by Pearson’s correlation analysis.

The results are as follows: the reaction degree of carrier elements is generally higher than that of information elements, of which the representative architecture is the main constituent element of locality; folk customs, traditional activities and other intangible cultural heritage in historic areas receive only slight attention and need to be further stressed; controlled by non-human factors, permanent elements bear a high degree of autocorrelation; and emerging tourism and business activities have, to some extent, grown into constituent parts of the locality elements in historic areas.

This paper seeks to strike a dynamic balance between city renewal and historic area protection, providing a reference for understanding the dynamics of locality.

This paper examines the effect of board reforms on managerial risk-taking incentive provision in state-owned enterprises (SOEs) whose managers are undue risk-averse.

We use the staggered implementation of board reforms in Chinese central government-controlled state-owned enterprises (CSOEs) as an exogenous shock to board governance. We collect data on board reforms for a set of pilot CSOEs during the period 2005 to 2020 from the State-owned Assets Supervision and Administration Commission (SASAC) website by hand. We use a generalized difference-in-difference (DID) design to test the effect of staggered board reform adoption on managerial risk-taking incentive provision.

We find a positive relationship between board reforms and risk-taking inventive provision, i.e. pay-performance sensitivity, promotion-performance sensitivity and performance target difficulty. The documented relationship is stronger when the value of risk-taking is higher. We also find that board reforms lead to greater risky but value-enhancing investments and that managerial risk-taking incentive provision acts as an important channel through which board reforms improve value-enhancing risk-taking.

Our findings suggest that board reforms that improve board governance are effective in addressing risk-related agency conflicts in emerging markets. The findings also highlight the importance of managerial risk-taking incentive provision in inducing risky but value-enhancing investments.

This study aims to reveal the room-temperature effect of a superconducting gravimeter prototype, which will guide its subsequent optimization to improve its gravimetric measurement accuracy.

Without leveling, the prototype output signal, tilt data and room temperature were measured under steady operating conditions. After analyzing the correlations of the three data sets, the residuals of the prototype’s output signal were compensated using the tilt data and the geodynamic effects (ocean tide loading, atmospheric loading and the gravitational effect of polar motion) were then corrected.

The remaining residuals after correction may be caused by small tilt variations that are due to the sensor chamber temperature and radiation shield temperature changes. These small tilt variations were submerged in the tilt signal noise. Although the peak-to-peak noise of the tiltmeter does not exceed 15 µrad, it can still produce gravimetric deviations above 60 µGal when the prototype is significantly tilted.

This study analyzes in detail the room-temperature effect of a superconducting gravimeter prototype, introduces the tilt effect of the relative gravimeters to compensate for the gravimetric deviations and emphasizes that the improvement of fine leveling and the accuracy of the tiltmeter are key requirements for the prototype to perform high-accuracy gravity measurement tasks.

The essence of “Chinese element” has been pinpointed as the representation of national cultural archetype resource of China, which reflects to the overall power enhancement of China. Applying the Chinese national cultural archetype resource, which will be used for promoting the Chinese Brand internationalization, aims for the consumers' approval with the hope of integrating and spreading the unique cultural advantage of Chinese brand. The recognizing of Chinese brand's cultural archetype in this paper has constituted the basis of Chinese brand's cultural archetype strategy.

Based on the Grounded Theory, this paper has collected and analyzed the value symbols, character images and theme stories of Chinese narrative advertisements and constructed the cultural archetype framework of Chinese brands. This paper makes a comprehensive application of Charmaz's constructivist analysis and the main axis analysis and inspection method advocated by Strauss, with the aim of building a more objective and systematic theoretical framework for the Chinese brand cultural archetype.

In this framework, it revealed: (1) Chinese brand's cultural archetype can be divided into 12 concrete archetypes according to individual's relationship with self, the other, community and nature; (2) Consumers' different ways of self-categorization are attributed as the essential difference among various archetypes. This paper also compared and analyzed the differences between Chinese and Western cultural archetypes from three perspectives, formation of social structure, pedigree of myth and character's feature.

This paper has certain innovative significance to the theoretical construction of the archetype of Chinese brand culture. First, based on the cultural perspective, this paper applied the cultural psychological connotation of archetype to the brand research across culture, which is more conducive to the researchers' investigation of the cultural psychology of consumers in the cross-cultural context? Second, based on the identification and comparative study of Chinese brand culture archetype, it provides a new expansion and supplement for the research on brand internationalization and globalization in emerging countries.

There is coupling between the branches of mobile parallel robots, similar to traditional parallel mechanisms, but there is currently relatively little research on the coupling problem between the branches of mobile parallel robots.

This study optimizes the coupling analysis method of traditional parallel mechanisms, treats the mobile parallel mechanism as a whole, takes the motion of the active pair as input and the overall motion of the mobile parallel mechanism as output and analyzes the input–output characteristics of the mobile parallel mechanism. Moreover, this study applies this theory to a mobile parallel mechanism, designs control logic and finally conducts simulation and physical verification.

This study proposes a coupling analysis method suitable for parallel mobile robots and designs the control logic of their active pair based on the results of their coupling analysis. This study designs a multimode variable coupling parallel mobile robot, which can change the coupling of the mechanism by changing its own branch chain structure, so that it can switch between different coupling configurations to meet the different needs brought by different terrains.

The work presented in this paper propose a method for analyzing the coupling of mobile parallel robots and simplify their control logic by applying coupling theory to the design of mobile parallel robots. This study conducts simulation and physical experiments, thereby filling the gap in the coupling analysis of parallel mobile robots and laying the foundation for the research of uncoupled parallel mobile robots.

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.

The increase of life expectancy leads to the elderly living with one or more chronic illnesses. Communication between the elderly and the health-care professional is fundamental but can be difficult. For that reason, it is common to find the patient with an accompanying family member in the doctor’s surgery. The purpose of this paper is to analyze one of the possible actions of the companion during the provision of the medical service: the co-creation of value (through its two dimensions: coproduction and value-in-use) and its effects on the satisfaction of both the companion and the elderly patient.

A model has been tested through a system of structural equations using the statistical package EQS 6.2. The sample used is made up of 1,814 informants (907 companions and 907 patients).

The importance of coproduction between the accompanying person and the health-care professional is shown, to obtain greater levels of satisfaction (of the companion and the patient), whereas a negative role is conferred to the dimension value-in-use. This paper shows a positive impact of the satisfaction of the companion on that of the patient.

It is necessary to have health-care professionals who play a proactive role when facilitating the participation in the appointment with the doctor so as not to leave the initiative of participation in the hands of the companions.

Chronic illnesses are an important focal point of medical attention. Good management of the relations between those involved is fundamental for the diagnosis and adherence to treatment.

This chapter provides a survey of alternative methodologies for measuring and comparing productivity and efficiency of airlines, and reviews representative empirical studies. The survey shows the apparent shift from index procedures and traditional OLS estimation of production and cost functions to stochastic frontier methods and Data Envelopment Analysis (DEA) methods over the past three decades. Most of the airline productivity and efficiency studies over the last decade adopt some variant of DEA methods. Researchers in the 1980s and 1990s were mostly interested in the effects of deregulation and liberalization on airline productivity and efficiency as well as the effects of ownership and governance structure. Since the 2000s, however, studies tend to focus on how business models and management strategies affect the performance of airlines. Environmental efficiency now becomes an important area of airline productivity and efficiency studies, focusing on CO₂ emission as a negative or undesirable output. Despite the fact that quality of service is an important aspect of airline business, limited attempts have been made to incorporate quality of service in productivity and efficiency analysis.

The purpose of this paper is to conduct a thorough study of the current research status and trends of Artificial Intelligence-Generated Content (AIGC), which is thriving and exerting significant influences on society, the economy and technology. This study will encompass both the ample opportunities and the array of emerging risks and challenges associated with AIGC. Furthermore, this paper seeks to propose practical optimization strategies to facilitate its continued development.

A total of 12,702 documents in Scopus, CNKI and Altmetric.com databases are analyzed in this paper. The visualization tools of CiteSpace and Netdraw are used to systematically analyze AIGC from macro, meso and micro perspectives based on bibliometric indicators. The analysis is combined with altmetrics indicators to identify hotspots in AIGC-related research and predict future development trends. Finally, substantive optimization suggestions for the development of AIGC are put forward.

Research has found that firstly, both domestic and international research in the field of AIGC is actively catching up with the pace of the era. Institutions and authors recognize the indispensability of collaboration, leading to the emergence of interdisciplinary cooperation trends. Secondly, at the thematic research level, both domestic and international studies cover the overall trends of AIGC, including technology, applications, challenges and coping strategies. However, international scholars tend to focus more on technological breakthroughs, while domestic researchers emphasize the formulation of national laws and regulations. Finally, through the analysis of hotspots and trends, it is predicted that future research will focus more on addressing the legal issues regarding the originality of AIGC, enhancing its interactivity, optimizing its applications, emphasizing ethical considerations and efficiently addressing major social issues such as pandemics using AIGC technology. Corresponding optimization strategies are proposed to ensure the development of AIGC is consistent with global consensus and values, creating a beneficial environment for its sustainable development.

Firstly, this paper integrates data from three databases and uses multiple software tools to conduct a comparative analysis of the research trends in AIGC from both domestic and international perspectives. Secondly, this paper not only analyzes the academic influence of AIGC-related research through bibliometric indicators but also combines altmetrics indicators to explore the public’s attitude toward AIGC. This method systematically reveals the overall development trends, leading institutions and researchers, thematic research areas, hotspot evolution and future development trends of AIGC-related research, providing theoretical references for subsequent scholars in AIGC research. Additionally, this paper helps governments, institutions and organizations to precisely and wisely formulate policies and investments, as well as to effectively comprehend the development trends of AIGC and promote the advancement of AIGC technology and applications.