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The purpose of this paper is to study the effect of on device performance by selectively annealing ITO substrates and TPD:PVK layers of the OLED at different temperatures with a certain annealing time.

Thermal annealing was carried out on the ITO anode at different temperatures (150, 350, 500°C) with a constant time (100 min); but also before the deposition of the tris(8‐hydroxyquinolato) aluminum (Alq₃) layer, at the same time, thermal treatment was carried out on the hole transporting layers (TPD:PVK layers) at different temperatures (70, 90, 110°C), and the annealing time was 30 min. We fabricated a novel device with the structure of Al/LiF/Alq₃/TPD:PVK/NiO/ITO/Glass, and tested the sheet resistance, SEM and XRD of ITO anode after annealing, at the same we also tested the I‐V, L‐V and current efficiency characteristics of OLED.

When the TPD:PVK layers were annealed at 90°C with 30 min annealing time and ITO substrates were annealed at 350°C with a constant annealing time (100 min), we find that the OLED shows obvious performance improvement, which is attributable to the fact that annealing reduces defects and improves the interface structures of organics and organic/ITO interface. On the other hand, an annealing TPD:PVK layers would slow and even impede the transport of holes, and finally leads to more balanced electron and hole injection processes.

The paper shows that the annealing method can be used to prepare high‐performance organic light‐emitting device.

The diagnosis and prediction methods used for estimating the health conditions of the bearing are of great significance in modern petrochemical industries. This paper aims to discuss the accuracy and stability of improved empirical mode decomposition (EMD) algorithm in bearing fault diagnosis.

This paper adopts the improved adaptive complementary ensemble empirical mode decomposition (ICEEMD) to process the nonlinear and nonstationary signals. Two data sets including a multistage centrifugal fan data set from the laboratory and a motor bearing data set from the Case Western Reserve University are used to perform experiments. Furthermore, the proposed fault diagnosis method, combined with intelligent methods, is evaluated by using two data sets. The proposed method achieved accuracies of 99.62% and 99.17%. Through the experiment of two data, it can be seen that the proposed algorithm has excellent performance in the accuracy and stability of diagnosis.

According to the review papers, as one of the effective decomposition methods to deal with nonlinear nonstationary signals, the method based on EMD has been widely used in bearing fault diagnosis. However, EMD is often used to figure out the nonlinear nonstationarity of fault data, but the traditional EMD is prone to modal confusion, and the white noise in signal reconstruction is difficult to eliminate.

In this paper only the top three optimal intrinsic mode functions (IMFs) are selected, but IMFs with less correlation cannot completely deny their value. Considering the actual working conditions of petrochemical units, the feasibility of this method in compound fault diagnosis needs to be studied.

Different from traditional methods, ICEEMD not only does not need human intervention and setting but also improves the extraction efficiency of feature information. Then, it is combined with a data-driven approach to complete the data preprocessing, and further carries out the fault identification and classification with the optimized convolutional neural network.

The purpose of this paper is to establish an exponentially weighted moving average (EWMA) control chart for monitoring the mean level of Gompertz lifetimes with type‐I censoring.

The proposed control chart is developed based on the conditional expected values (CEVs). The control limits are determined numerically with an algorithm.

Compared with the EWMA CEV control charts of Zhang and Chen, numerical results indicate that the proposed control chart has good performance to detect mean shifts for Gompertz lifetimes either in decrease or in larger increase with type‐I censoring in terms of the average run length (ARL).

The paper shows that, based on the proposed method, practitioners can monitor the mean level of Gompertz lifetimes via an EWMA CEV control chart with type‐I censoring.

This study aims to examine the consequences when audit committees have different economic incentives (i.e. incentive-based compensation) to switch auditors.

The author focuses on companies experiencing an auditor switching event (client-initiated dismissals) and uses Heckman’s (1997) two-stage estimation procedure to control endogenous bias. Audit committee quality is measured by the level of incentive-based compensation. Accrual quality and abnormal audit fees are examined over the periods of auditor switches.

Using 1,087 US companies between 2006 and 2014, the author found that audit committees’ incentive-based compensation is negatively (positively) associated with accruals quality (abnormal audit fees) only when companies switch from Big 4 to non-Big 4 auditors or switch within non-Big 4 auditors. For companies that switch from non-Big 4 to Big 4 auditors, she found no evidence.

This study provides a detailed discussion of the consequences of audit committee quality. The findings also contribute to the literature by concluding that economic incentives are associated with ineffective oversight, particularly after auditor switches.

Sarbanes–Oxley Act and its associated regulations significantly expanded the oversight role of audit committees. However, regulators bypassed restrictions on audit committee compensation. Accordingly, the author suggests that regulators focus on the issue of economic incentives to improve audit committee quality.

Minimal research has been conducted on the role of audit committees when companies switch to a new external auditor. The author shows that when companies switch auditors, incentive-based compensation significantly affects the monitoring quality of audit committees.

This study aims to undertake the evaluation and examination of the productivity change of the Egyptian banking sector. Using a novel data set covering 14 banks operating in the Egyptian market from 1997 to 2013. We use a nonparametric approach (based on data envelopment analysis (DEA)) to investigate the productivity change in the Egyptian banking sector. Input-oriented Malmquist indices of productivity change are estimated with DEA to measure total factor productivity (TFP) change. The TFP changes are decomposed into the product of technological change and technical efficiency change (catch-up). In the second stage, we study potential determinants of productivity change using a regression model. We find that the Egyptian banking sector as a whole shows a productivity regress of 0.9% per year, mainly due to the technological improvements. The estimated regression model identifies some variables that significantly influence the productivity of banks in Egypt. The banks with higher loan to deposit ratio and higher returns on equity have higher productivity growth reflecting on their strong strategic and managerial skills. The size of a bank seems to be associated with an increase in productivity. The maturity of a bank (measured by age) is associated with higher productivity. The NIM and NIETA variables do not seem to be affecting the productivity of banks. Surprisingly, our results reveal that the financial crisis was negatively and statistically insignificant, hence it had no effect on the Egyptian banks.

The study aims to analyze guest comments on the Uber Eats food delivery app (FDA) in the USA during the April–June 2020 COVID-19 pandemic lockdown period. Three aspects influencing customer satisfaction with the FDA were evaluated in this study: (1) performance on the app, (2) product quality and (3) service quality.

One thousand customer comments posted on the Uber Eats Google Play app from April 1 to June 30, 2020 were analyzed in this study. The text mining technique was applied to discover the hidden, but meaningful patterns from the unstructured text. Content analysis was applied to systematically analyze the text into organized categories and themes.

Among the three dimensions evaluated in this study, the most important dimension regarding customers' perceptions toward the FDA was the service quality dimension (40.02%), followed by the FDA's performance dimension (39.43%) and the product quality dimension (20.54%) was least important. Additionally, customers' perceptions towards the three dimensions were all unfavorable and there were more negative comments than the positive comments: FDAs (P/N = 0.728), product quality (P/N = 0.60) and service quality (P/N = 0.865).

Previous studies investigating FDAs assessed solely the performance of the app. However, customers' experience of a food delivery service is comprised of multiple components including the app, the restaurant and the delivery driver. To fill the void, this study evaluated a third-party app performance, product quality and service quality to capture the totality of customers' food delivery service experience.

In recent years, with the rapid development of the Internet and e-commerce, the online retail business has grown rapidly. E-commerce platforms can track different click data to understand consumer behavior and demand preferences, so as to make better demand forecasts, and strategically share this information with upstream suppliers. When the platform charges a certain fee for the shared data, the suppliers face the question of whether to purchase demand information. This article aims to analyze the influence of price competition and advertising competition on the suppliers' decisions to purchase information and the online platform for data pricing.

By using static game with incomplete information, this paper explores information-sharing strategies of an online platform with two competitive brand suppliers. The authors use Nash game to analyze the suppliers' purchasing information decision and then obtain the optimal information price of the online platform with information-sharing contract.

This paper shows that demand information sharing benefits both the platform and the suppliers. Without information contracts, the online platform is willing to share demand information with at least one supplier. Especially, when the consumer's sensitivity to advertising is larger and the commission fee charged by the online platform is small, the online platforms will share information with only one supplier. Based on the game outcomes between the suppliers, two pricing strategies for information are proposed under which at least one supplier purchases information. If the consumers are less (more) sensitive to advertising competition, pricing strategy of the online platform induces both suppliers (only one supplier) to purchase information.

At present, most of the information-sharing articles are based on the traditional purchase and sale mode. Based on the background of e-commerce, this paper examines the online platform's information-sharing strategies, which has certain innovation. In addition, the results show that the information-sharing strategy of the online platform is affected by both the price and advertising competitiveness, which provides a new expansion and supplement for the information-sharing literature.

Little information on dissemination of publications on policing issues in East Asia in which one-fifth of the world's population lives is available. The research questions for the paper are: how extensive is the coverage of papers focussing on policing in East Asia; on which East Asian countries have the papers covered during the 14-year period from 2000 to 2013; what are the topics/primary issues of policing in East Asia covered across the journals; and what are the affiliations represented of authors who have published papers on policing in East Asia. The paper aims to discuss these issues.

This study is a content analysis of major policing specialty journals listed in the Social Science Citation Index (SSCI) in terms of the number and focus of studies on East Asian police papers. Data came from 1,123 papers published in three policing journals of Police Quarterly, Policing: An International Journal of Police Strategies & Management, and Policing and Society: An International Journal of Research and Policy during the period of 2000-2013.

Only 3.4 percent (n=38) of the 1,123 articles published in the three journals were on policing issues in East Asia nations. The vast majority (76.3 percent) were published in Policing: An International Journal of Police Strategies & Management. Staff issue was the most frequently researched topic. In total, 42 percent of the papers were on South Korean policing issues, followed by 31 percent on Chinese policing topics. Finally, about 45 percent of the papers were written by only US-affiliated authors, 40 percent by authors affiliated with institutions in East Asia, and only 16 percent were written in collaboration between authors associated with USA and East Asian institutions.

The main intent of this study is to provide information seekers with a guide to what research on policing in East Asia is being published.

This study aims to present an optical alignment and compensation control of die bonder for chips containing through-silicon vias and develop three-dimensional integrated circuit stacked packaging for compact size and multifunction.

The machine vision, optical alignment method and sub-pixel technology in dynamic imaging condition are used. Through a comparison of reference image, the chip alignment calibration can improve machine accuracy and stability.

According to the experimental data and preliminary results of the analysis, accuracy can be achieved within the desired range, and the accuracy is much better than traditional die bonder equipment. The results help further research in die bonder for chips containing through-silicon vias.

In subsequent testing of the chip, the machine can simultaneously test multiple chips to save test time and increase productivity.