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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.

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.

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.

This study aims to measure the acceptance of digital resources by integrating knowledge management (KM) factors (i.e. acquisition, sharing, application and protection) into the factors of the technology acceptance model (TAM) (i.e. perceived ease of use and perceived usefulness) and their impact on actual system use through behavioural intention.

Using the quantitative research method, a survey was conducted of the public sector universities of Punjab, Pakistan. Data were collected from postgraduate students and analysed using partial least squares structural equation modelling.

The findings showed that the factors of KM with the integration of TAM significantly impact the acceptance of digital resources. The study’s hypotheses are all supported, and the findings demonstrated that knowledge acquisition, knowledge sharing, knowledge application and knowledge protection significantly influenced perceived usefulness and perceived ease of use, and that these factors are positively correlated with behavioural intentions to use digital resources.

This study has considerable significant implications for policymakers, developers and practitioners in designing digital resources. This study will also assist librarians to discover areas for development that may enhance the use of digital resources among users

Blockchain is a relatively new technology. Although it has a high potential to influence organizational strategies for adoption into respective operations, it has not been widely explored yet. This study aims to assess the sectoral diversity in the timing of organizational adoption of blockchain through selected organizational factors.

A survey was conducted based on a sample of 208 IT professionals. The data was collected using an instrument containing 17 questions. The existence of sector diversity was statistically analyzed using the Least Square Regression method.

The results indicate that, except for management support and perceived ease of use, all the other factors in the analysis significantly influence sector diversity in terms of blockchain adoption timing.

Although blockchain has received attention from researchers, to the best of the authors' knowledge, there is no published work in the literature that explores the organizational factors influencing sectoral differences in the timing of blockchain technology adoption. Therefore, our work is unique in the related literature since we present analyses for the diversity between public and private sectors by modeling the factors affecting the intentions for the timing of blockchain adoption as part of the organizations' IT infrastructure.

Recent research has drawn attention to the tension between the Central and local governments in China regarding their roles in environmental protection. This paper aims to explore this tension and examine the extent to which local/provincial government’s environmental oversight has influenced the quality of corporate environmental disclosure in China.

A sample of 198 listed companies in heavily polluting industries were selected to examine the relationship between their environmental disclosure quality and the respective local government’s environmental oversight level.

The results provide evidence that local/provincial government’s environmental oversight significantly influences environmental disclosure in China. Despite the coercive pressure from the powerful Central government on corporate environmental disclosure, local/provincial governments are able to buffer the pressure and adjust the intensity of their environmental oversight on companies during the implementation of central policies to retain local economic and political interests. This may partially explain the persistent issue of low environmental disclosure quality in China.

This study enriches our understanding of the significant role of local governments in China in enhancing or sometimes discounting the regulatory enforcement of the Central government on corporate environmental disclosure, pointing to the need for concerted efforts by both local and Central governments to advance environmental disclosure development.

Research on environmental disclosure in developed countries has been well established in the literature. However, such research in developing nations is still limited, especially in China, the world largest developing country. The existing literature on environmental disclosure in China links it with either market demands, or regulatory enforcement from the Central government. The importance of local/provincial governments and their environmental oversight has long been ignored, which motivates this research.