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This paper aims to provide an optimization method of workflow for publishing houses and electronic book (e-book) studies in the field of digital publishing.

Based on the studies of publishing houses in Beijing, the present conversion workflow is illustrated using a functional modeling methodology. Then, the workflow is analyzed using 5W1H (why, who, what, where, when, how) methodology and optimized using ECRSI (eliminate, combine, rearrange, simplify and increase) principles. To validate the optimization effect, the workflow before and after optimization are generated and implemented by the ExtendSim® simulation software.

The simulation results show that under similar circumstances, both quantity and quality of the products are improved after optimization, which indicate that the optimization method is effective.

Electronic PUBlication (EPUB) has significant requirements to satisfy the needs of the mobile reading market and to earn increased profits, whereas some e-books are still preserved in a portable document format (PDF). This study results in the enhanced EPUB quality and production efficiency of the PDF-to-EPUB format conversion workflow in publishing houses. Publishing houses around the world can refer to this study to make a similar optimization when handling PDF-to-EPUB.

This research introduces the traditional industrial engineering analytical techniques to the workflow optimization of e-book conversion. Compared with the most of other methods used to optimize workflow, this method is simpler, more efficient and more suitable for e-book format conversion.

Optimization of light-emitting diodes’ (LEDs’) design together with long-term reliability is directly correlated with their photometric, electric and thermal characteristics. For a given thermal layout of the LED system, the maximum luminous flux occurs at an optimal electrical input power and can be determined using a photo-electro-thermal (PET) theory. The purpose of this study is to extend the application of the luminous flux equation in PET theory for low-power (LP) LEDs.

LP surface-mounted device LEDs were mounted on substrates of different thermal resistances. Three LEDs were attached to substrates which were flame-retardant fiberglass epoxy (FR4) and two aluminum-based metal core printed circuit boards (MCPCBs) with thermal conductivities of about 1.0 W/m.K, 2.0 W/m.K and 5.0 W/m.K, respectively. The conjunction of thermal transient tester and thermal and radiometric characterization of LEDs system was used to measure the thermal and optical parameters of the LEDs at a certain range of input current and temperature.

The validation of the extended application of the luminous flux equation was confirmed via a good agreement between the practical and theoretical results. The outcomes show that the optimum luminous flux is 25.51, 31.91 and 37.01 lm for the LEDs on the FR4 and the two MCPCBs, respectively. Accordingly, the stipulated maximum electrical input power in the LED datasheet (0.185 W) is shifted to 0.6284, 0.6963 and 0.8838 W between the three substrates.

Using a large number of LP LEDs is preferred than high-power (HP) LEDs for the same system power to augment the heat transfer and provide a higher luminous flux. The PET theory equations have been applied to HP LEDs using heatsinks with various thermal resistances. In this work, the PET theory luminous flux equation was extended to be used for Indium Gallium Aluminum Phosphide LP LEDs attached to the substrates with dissimilar thermal resistances.

In this age of exponential knowledge growth, where wireless internet is playing a dominant role, the concerned authorities of higher education have to ensure that this tool remains within the reach of the students. However, there has been as yet little research indicating its success in China. This paper aims to examine factors that influence students’ satisfaction (SAT) in using wireless internet in higher education for the purpose of learning. The second aim of this study is to identify if gender has a moderating effect on students’ SAT in using wireless internet in higher education.

Data from a total of 283 students from five colleges of a comprehensive public university in China (Foreign Language Studies, Business, Education, Biology and Chemistry, and Mathematics and Engineering) were collected for this study. The reliability and validity of the measurement scale were established through a Rasch model using Winsteps version 3.94. The technology satisfaction model (TSM) was validated applying structural equation modelling (SEM) using AMOS to test the causal relationships among the constructs.

The results of this study revealed that students’ SAT was directly influenced by perceived usefulness (PU) and ease of use of wireless internet. Besides, students’ perceived ease of use (PEU) and usefulness were directly affected by their computer self-efficacy. On the other hand, students’ computer self-efficacy had an indirect effect on their SAT mediated by ease of use and perceived usefulness, respectively. The findings also discovered that gender did exert effect as a moderating variable towards students’ SAT in using wireless internet in higher education.

The TSM was shown to be a useful model to measure students’ SAT in using wireless internet in a different culture.

To achieve this aim, a TSM on the potential factors contributing to student SAT was developed from the literature and validated in this study. Whereas, the TSM has been developed and validated in Malaysia.

The purpose of this paper is to investigate the effects of multi‐walled carbon nanotubes (MWNTs) on the mechanical, thermal and electrical conductivity properties of polyurethane (PU) by in situ polymerisation of MWNTs and PU.

A number of analytical techniques, including Fourier transform infrared spectroscopy and X‐ray photoelectron spectroscopy, were employed to assess the effects of acid treatment on MWNTs. The mechanical and thermal properties of PU, MWNTs and PU composites were characterised using a tensile tester machine and dynamic mechanical analysis. The electoral conductivity properties of the materials were characterised by ohmmeter.

It was found that desirable modifications to MWNTs occurred after acid treatment, thus mainly carboxylic acid groups were introduced onto the surface of MWNTs. And the acid‐treated MWNTs could improve the mechanical, thermal and electrical conductivity properties of PU by in situ polymerisation of MWNTs and PU successfully.

The investigation established a method to synthesise MWNTs and PU composites by in situ polymerisation. The mechanical, thermal and electrical conductivity properties of PU could be improved by the inclusion of MWNTs.

The paper establishes a method to synthesise MWNTs and PU composites by in situ polymerisation; and the effects of MWNTs on modifying mechanical, thermal and electrical conductivity properties of PU by in situ polymerisation are investigated in detail.

This paper aims to improve the refractive index sensor performance for analytes with large refractive index by adopting the technology of microstructured fiber (MF) and surface plasmon resonance (SPR).

The structure adopts an MF with a hexagonal lattice cladding structure composed of all-circular air holes, and three defect regions are introduced. The liquid analyte that needs to be tested is filled in the defect area. The surface plasmon polarition mode is generated and coupled with the core mode, thus forming a refractive index sensing channel. When the resonance conditions are satisfied, the resonance wavelength will be changed with the refractive index of the liquid analyte. All parameters that may affect the performance of the sensor are numerical simulated, and the structure is optimized through a large number of calculations.

The results demonstrate that the maximum dynamic sensitivity (S_R) can reach to 24,260 nm/RIU, and the average sensitivity (S_R-AV) can reach to 18,046 nm/RIU when the refractive index range is from 1.42 to 1.47. Besides, the sensitivity linearity (R²) is approximately 0.965, and its resolution is 4.1 × 10^–6 RIU. The comparison with some literature results shown that the proposed sensor has certain advantages over the sensors reported in these literatures.

This work proposed an SPR-based refractive index sensor with a simple MF structure. It has a certain reference significance for the design and optimization of SPR-based MF sensors. Moreover, owing to its simple structure, high refractive index sensitivity and linear sensing performance, this sensor will play an important role in the detection of high refractive index liquid analytes.

The purpose of this study is to investigate the reasons (for and against) affecting owners' attitudes and intentions to use digital marketing (DM) strategies in tourism and hospitality (T&H) small and medium enterprises (SMEs), by employing the behavioral reasoning theory (BRT).

A survey method was used to collect data from 306 T&H (SMEs) owners and analyze the data through partial least square structural equation modelling (PLS-SEM).

The study results indicate that reasons significantly affect owners' attitudes and intentions to use DM in T&H (SMEs). The “RF” was as follows: perceived ease of use (PEU), perceived usefulness (PU), and trust in DM professionals” and the “RA” technological anxiety, usage barriers (UB), and perceived complexity (PC) effect on owners’ attitudes and intentions to use DM. Also, it indicates that openness to change value significantly affects the “RF” insignificant with “RA” and attitude.

The findings of this study emphasize that if owners/managers, governments, and policymakers overcome the “RA” that discourages and raises the knowledge about the “RF” in the adoption of DM, then the usage intention of DM strategies can rise in T&H (SMEs).

This study is the first to investigate the reasons (for and against) the owner’s attitude and intention to use DM in T&H (SMEs) by utilizing behavioral reasoning theory (BRT), technology acceptance model (TAM), and innovation resistance theory (IRT).

High economic policy uncertainty forces firms to accumulate a higher level of cash than during normal business periods. However, it is not evident that economic policy uncertainty has a homogeneous impact across cash-holding distributions. This paper aims to study the impact of economic policy uncertainty, leverage and their interaction on cash-holding distributions.

This study adopted a quantile regression approach to examine the influence of economic policy uncertainty and firm leverage on firm-level cash-holding distributions. To investigate the influence across quantiles, the author estimated 19 quantiles between 0.05 and 0.95.

This study finds that both economic policy uncertainty and firm leverage significantly affect firm-level cash-holding distributions heterogeneously. But, the impact of the interaction of these two variables is significant only for firms placed in the 60th to 85th quantiles of cash holding distribution.

The study adds to the existing knowledge of determinants of firm-level cash holdings but takes exogenous variables as economic policy uncertainty. The paper builds on a unique sample setting wherein, the cash holdings of all nonfinancial firms have increased many folds, including housing companies in an emerging economy.

One major problem in the lighting industry is the thermal management of the devices. Handling of thermal resistance from solder point to the ambiance of the light-emitting diode (LED) package is linked to the external thermal management that includes a selection of the cooling mode, design of heatsink/substrate and thermal interface material (TIM). Among the significant factors that increase the light output of the of the LED system are efficient substrate and TIM. In this work, the influence of TIM on the luminous flux performance of commercial indium gallium aluminium phosphide (InGaAlP) low-power (LP) LEDs was investigated.

One batch of LEDs was mounted directly onto substrates which were glass-reinforced epoxy (FR4) and aluminium-based metal-core printed circuit boards (MCPCBs) with a dielectric layer of different thermal conductivities. Another batch of LEDs was prepared in a similar way, but a layer of TIM was embedded between the LED package and substrate. The TIMs were thermally conductive epoxy (TCE) and thermally conductive adhesive (TCA). The LED parameters were measured by using the integrated system of thermal transient tester (T3Ster) and thermal-radiometric characterization of LEDs at various input currents.

With the employment of TIM, the authors found that the LED’s maximum luminous flux was significantly higher than the value mentioned in the LED datasheet, and that a significant reduction in thermal resistance and junction temperature was revealed. The results showed that for a system with low thermal resistance, the maximum luminous flux appeared to occur at a higher power level. It was found that the maximum luminous flux was 24.10, 28.40 and 36.00 lm for the LEDs mounted on the FR4 and two MCPCBs, respectively. After TCA application on the LEDs, the maximum luminous flux values were 32.70, 36.60 and 37.60 lm for the FR4 and MCPCBs, respectively. Moreover, the findings demonstrated that the performance of the LED mounted on the FR4 substrate was more affected by the employment of the TIM than that of MCPCBs.

One of the major problems in the lighting industry is the thermal management of the device. In many low-power LED applications, the air gap between the two solder pads is not filled up. Heat flow is restricted by the air gap leading to thermal build-up and higher thermal resistance resulting in lower maximum luminous flux. Among the significant factors that increase the light output of the LED system are efficient substrate and TIM.

The findings in this work can be used as a method to improve thermal management of LP LEDs by applying thermal interface materials that can offer more efficient and brighter LP LEDs. Using aluminium-based substrates can also offer similar benefits.

Users of LP LEDs can benefit from the findings in this work. Brighter automotive lighting (signalling and backlighting) can be achieved, and better automotive lighting can offer better safety for the people on the street, especially during raining and foggy weather. User can also use a lower LED power rating to achieve similar brightness level with LED with higher power rating.

Better thermal management of commercial LP LEDs was achieved with the employment of thermal interface materials resulting in lower thermal resistance, lower junction temperature and brighter LEDs.

This study aims to identify the key attributes of esports venues as perceived by spectators. Using the stimulus-organism-response framework, it also examines how these attributes influence customer experience, satisfaction and re-attendance intentions.

This mixed-methods research comprises two main stages. In the qualitative stage (Stage 1), we conducted a literature review, interviews with live esports event attendees and observations at two esports events to identify key esports venue attributes from spectators’ perspectives. In the quantitative stage (Stage 2), we recruited 564 esports game attendees at two live events to validate a measurement scale developed from the qualitative procedures. We also examined the relationships between venue attributes and the three spectator outcomes by using structural equation modeling.

Five key perspectives of esports venue attributes emerged from the qualitative analysis: (1) stage and stage lighting, (2) Internet infrastructure, (3) visibility of display screens, (4) concourse layout and (5) seating comfort. These dimensions were validated through exploratory and confirmatory factor analyses and were found to directly influence spectator experience and satisfaction, but not re-attendance intentions.

This study provides pioneering insights into the specific esports venue attributes that drive spectator outcomes. The findings offer valuable directions for future esports research and practical strategies for esports venue management.

The transpiration has been recognized as one of the most effective thermal protection methods for future hypersonic vehicles. To improve efficiency and safety, it is urgent to optimize the design of the transpiration system for heat and drag reduction. The purpose of this paper is to investigate the effects of transpiration on heat and drag reduction.

A chemical nonequilibrium flow model with the transpiration is established by using Navier–Stokes equations, the shear-stress transport turbulence model, thermodynamic properties and the Gupta chemical kinetics model. The solver programmed for this model is verified by comparing with experimental results in the literature. Effects of air injection on the flow field, the aerodynamic resistance and the surface heat flux are calculated with the hypersonic flow past a blunt body. Furthermore, a modified blocking coefficient formula is proposed.

Numerical results show that the transpiration can reduce the aerodynamic resistance and the surface heat flux observably and increase the shock wave standoff distance slightly. It is also manifested that the modified formula is in better agreement with the wind tunnel test results than the original formula.

The modified formula can expand the application range of the engineering method for the blocking coefficient. This study will be beneficial to carry out the optimal design of the transpiration system.