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Identification and characterization of organic pigments and dyes used in works of art and cultural heritage material such as prints, drawings, manuscripts, paintings, and textiles can provide important information for dating, authentication, and conservation treatment of these objects and studying art history in general. Applications of surface‐enhanced Raman scattering (SERS) for this purpose have recently attracted increasing attention of both academic scientists and museum researchers. This paper aims to review the latest development involving the emerging applications of SERS for the analysis of organic pigments and dyes used in works of art and cultural heritage material.

First, the importance of organic pigments and dyes in the studies of works of art and cultural heritage material and the challenges in their identification and characterization are briefly summarized. This is followed by a discussion on sampling considerations in the context of art and archaeology. Then the fundamental principle of SERS, SERS instrumentation and different types of SERS substrates are reviewed. Finally, selected examples of SERS applications to the identification of organic pigments and dyes, including the analysis of a couple of samples of artistic and archaeological interest, are presented and discussed.

The last few years have witnessed the emergence of SERS as a non‐destructive or micro‐destructive technique for the characterization of organic pigments and dyes found in artistic and archaeological objects. Spectroscopic and microscopic measurements using SERS have provided some novel information and answers to a wide variety of questions. However, SERS application to the field of art and archaeology is still in the fledging stage of development and requires closer collaboration between academic scientists and museum researchers. But the range of possible applications is broad. Future trends point to a strong need for the development of portable instruments for field applications.

By compiling this review, the authors hope to direct more attention toward SERS and bring together the expertise in the scientific, museum and art community to further explore the possibilities of SERS in rapid and direct identification of pigments and dyes under field conditions.

This paper aims to present a simplified method to analyze the transient characteristics of a fractional-order very high frequency (VHF) resonant boost converter. The transient analytical solutions of state variables obtained by this method could be used as a guide for parameter design and circuit optimization.

The VHF converter is decoupled into a simplified equivalent circuit model and described by the differential equation. The solution of the simplified equivalent circuit model is taken as the main oscillation component of the transient state variable. And the equivalent small parameter method (ESPM) and Kalman filter technology are used to solve the differential equation of the converter to obtain the steady-state ripple component. Then, by superimposing the abovementioned two parts, the approximate transient analytical solution can be acquired. Finally, the influence of the fractional order of the energy storage elements on the transient process of the converter is discussed.

The results from the proposed method agree well with those from simulations, which indicates that the proposed method can effectively analyze the transient characteristic of the fractional-order VHF converter, and the analytical solution derived from the proposed mathematical model shows sufficient accuracy.

This paper proposes for the first time a method to analyze the transient characteristics of a fractional-order VHF resonant boost converter. By combining the main oscillated solution derived from the simplified equivalent circuit model with the steady-state solution based on ESPM, this method can greatly reduce the computation amount to estimate the transient solution. In addition, the discussion on the order of fractional calculus of energy storage components can provide an auxiliary guidance for the selection of circuit parameters and the study of stability.

This rejoinder aims to critique some of the perspectives in Chen’s (2018) study on hospitality and host–guest paradigm in China.

In this preliminary probe into Chen’s study, critical analysis is performed on Chen’s approaches, whereas document analysis is applied to the relevant ancient Chinese writings. Translations are the author’s own unless indicated otherwise.

Chen’s views are problematic and supported by patchy evidence. “Hierarchy principle” and “host-centric foundation” do not hold up. In a series of asymmetrical comparisons, Chen goes a bit too far in arguing for uniqueness.

This rejoinder presents valid critiques of Chen’s study, thus directing future research in the right direction. It is of some significance to clarify Chen’s misrepresentations and offer a truer and fuller account of Chinese hospitality, given the difficulty for international scholars to validate Chen’s views because of language barrier and cultural unfamiliarity.

This study aims to investigate the role of aluminium (Al) in marine environment and the corrosion mechanism of galvalume coatings by conducting accelerated experiments and data analysis.

Samples were subjected to accelerated corrosion for 136 days via salt spray tests to simulate the natural conditions of marine environment and consequently accelerate the experiments. Subsequently, the samples were examined using various test methods, such as EDS, scanning electron microscopy (SEM), X-ray diffraction (XRD) and electrochemical impedance spectroscopy (EIS), and the obtained data were analysed.

Galvalume coatings comprised interdigitated zinc (Zn)-rich and dendritic Al-rich phases. Corrosion was observed to begin with a Zn-rich phase. The primary components of the corrosion product film were Al₂O₃ and Zn₅(OH)₈Cl₂·H₂O. It was confirmed that the role of Al was to form a dense protective film, thereby successfully blocking the entry of corrosive media and protecting the iron substrate.

This study provides a clearer understanding of the corrosion mechanism and kinetics of galvalume coatings in a simulated marine environment. In addition, the role of Al, which is rarely mentioned in the literature, was investigated.

The purpose of this paper is to maximize the load-carrying capacity (LCC) of a rotating ring, a numerical model optimizing both the surface and bottom shape of its surface textures is proposed.

The Reynolds equation is used to evaluate the film pressure and LCC obtained by integrating the film pressure is set as the objective function. Around the center of the computational domain, radial lines with an equal angle between adjacent ones are produced and the surface contour of textures is obtained by connecting the endpoints using a spline curve. The bottom profile is then obtained by connecting the endpoints of two vertical lines at the circumferential ends of textures. Lengths of these lines are set as design variables and genetic algorithm is used to solve optimization models.

Results show that optimum textures have an “apple-like” surface contour and a “wedge-like” bottom profile, which are both expressed by smooth spline curves. Optimum wedge-bottom textures generate higher LCC than optimum flat-bottom textures. Moreover, the optimum textures have the highest LCC compared with optimum grooves proposed previously, which validates the practical value of the current optimization model.

This work presents a comprehensive optimization method of texture geometry, which provides a new idea of the design of surface textures.

As researchers are writing a draft paper with incomplete structure or text, one of burdensome tasks is to deliberate about which references should be cited for one sentence or paragraph of this draft. In view of the rapid increase in the number of research papers, researchers desire to figure out a better way to do citation recommendations in developing their draft papers. The purpose of this paper is to propose citation recommendation algorithms that enable the acquisition of relevant citations for research papers that are still at the drafting stage. This study attempts to help researchers to select appropriate references among the vast amount of available papers and make draft papers complete in reference citation.

This study adopts a model for recommending citations for incomplete drafts. Four algorithms are proposed in this study. The first and second algorithms are unsupervised models, applying term frequency-inverse document frequency and WordNet technologies, respectively. The third and fourth algorithms are based on the second algorithm to integrate different weight adjustment strategies to improve performance.

The proposed recommendation method adopts three techniques, including using WordNet to transform vector and setting adjustment weights according to structural factors and the information completeness degree, to generate citation recommendation for incomplete drafts. The experiments show that all these three techniques can significantly improve the recommendation accuracy.

None of the methods employed in previous studies can recommend articles as references for incomplete drafts. This paper addresses the situation that a draft paper can be incomplete either in structure or text or both. Recommended references, however, can be still generated and inserted into any desired sentence of the draft paper.

This paper aims to improve the general circuit of driving and protection based on insulated gate bipolar transistor (IGBT) in dielectric barrier discharge power supply by designing a novel half-bridge inverter circuit with discrete components.

With one SG3524 chip, the structure based on discrete components is used to design the IGBT drive circuit. The driving waveform is isolated and sent out by photo-coupler 6N137. The protection circuit is realized by Hall sensor directly detecting the main circuit current, supplemented by a few components, including diodes, resistors, capacitors and triodes. It improves the reliability of the protection circuit.

In the driving circuit, the phase difference of signals from two channels are 180°. Moreover, when the duty cycle is set at 40%, it can ensure sufficient pulse width modulation response time. In the protection circuit, when over-current occurs, an intermittent output signal is automatically sent out. Furthermore, the over-current response time can be controlled independently. The peak voltage can be adjusted continuously from 0 to 30 kV with its frequency from 8 to 25 kHz and the power output up to 150 W.

The novel circuit of driving and protection makes not only its structure simpler and easier to be realized but also key parameters, such as frequency, the duty cycle and the driving voltage, continuously adjustable. Moreover, the power supply is suitable for other discharges such as corona discharge and jet discharge.

This study aims to examine the moment-to-moment (MTM) effects of in-consumption dynamic comments on consumers' responses to digital engagement and the underlying mechanisms involved, as well as the interactive role of advertisements embedded in short-form online video.

This study uses data extracted from 2,081 videos posted on the prominent Chinese online live platform, Bilibili. The hypotheses are tested using regression models and natural language processing.

The results indicate that the intensity of live comments at the beginning negatively affects users' digital engagement, while a corresponding increase in live comments at the end elicits a positive effect. A linear trend and peak difference in live comments intensity positively affect digital engagement, while the variability of live comment intensity exerts a negative effect. These MTM effects were driven by sentiments of live comments. Furthermore, in-video advertisements are likely to amplify the negative beginning effect on users' digital engagement and mitigate the negative variability of live comments.

This study is the first to examine the direct effects of MTM comments from the online temporal sequence perspective, differentiating the process- and performance-based engagement. The mechanism and interactive role of in-video advertisements were identified. These findings contribute to literature on interactive marketing and provide valuable guidance for influencer marketing.

As the application of gamification is gaining great attention and has grown increasingly, thousands of these applications can be easily obtained from mobile phone stores, thus causing intensified competition and discontinuance of use accordingly. Besides, though understanding what factors influence the discontinuance of use of information systems (ISs) is critical for theoretical as well as practical reasons, studies pertaining to the saliency of the final phase, termination of an IS, are still limited. As such, the purpose of this paper is to propose a holistic view to fulfill the above-mentioned research gaps based on the expectation-confirmation model with other salient factors such regret, habit and gamification app values.

The context of a fitness gamification app is investigated. A total of 210 valid responses were received, and structural equation modeling was applied for data analysis.

The findings of this paper are as follows: among all factors influencing discontinuance intention, regret is the strongest, habit is second and gamification is third; among all factors affecting user satisfaction, gamification app value is the strongest, confirmation is second, perceived usefulness (PU) and perceived ease of use are third and regret is the last one; for factors influencing users’ habits, satisfaction is the strongest, following by PU and frequency of prior use; confirmation negatively influences the degree of regret; and confirmation positively influences PU.

This study highlights the important determinants influencing users’ discontinuance intentions in the context of gamification apps by incorporating two overlooked factors, regret and habit. Besides, this study suggests that app designers can not only increase user’s perceived value through external cooperation with other alternatives, but can be through internal enhancement with diverse services development as well.

Cryptocurrency, an important application of blockchain technology, has gradually circulated, and its use has become widespread. While cryptocurrency is growing rapidly, potential risks are simultaneously emerging. Users thus may abandon their usage behavior of cryptocurrency, hindering the future development of cryptocurrency. While prior studies focus more on the intention to use cryptocurrency in the pre-adoption phase, less studies pay attention to discontinuance usage intention in the post-adoption phase. To fill this knowledge gap, this stfudy aims to explore factors that cause discontinuance usage intention regarding cryptocurrency.

Based on the net valence framework theoretically grounded on the theory of reason action, a dilemmatic dual-factor model is proposed to figure out cryptocurrency users' discontinuance usage intention from the perceived risk and perceived benefit. This study identifies four potential risks and three potential benefits that affect perceived risk and benefit. The model with nine hypotheses were developed, and research data were collected by a survey method. A total of 343 valid responses were received, and PLS-SEM with SmartPLS was utilized to test the nine hypotheses, with seven hypotheses supported empirically.

Our findings demonstrate that financial, legal and operational risks are critical to increase users' perceived risk, and perceived usefulness and seamless transactions play important roles in enhancing users' perceived benefit. Moreover, while perceived risk can increase users' discontinuance usage intention to cryptocurrency, perceived benefit can mitigate such intention.

This study contributes nascent knowledge to the literature by examining factors that influence discontinuous usage intention in regard to cryptocurrencies, to firms that have issued or attempted to issue cryptocurrencies and to the potential users of cryptocurrencies by adjusting the mode of operation and investment strategies and reducing user costs, achieving a win-win situation for firms and users.