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1 – 10 of over 1000
Article
Publication date: 30 September 2022

Gang Wang, Chenhui Xia, Bo Wang, Xinran Zhao, Yang Li and Ning Yang

A W-band antennas-in-packages (AIP) module with a hybrid stacked glass-compound wafer level fan-out process was presented. Heterogeneous radio frequency (RF) chips were integrated…

Abstract

Purpose

A W-band antennas-in-packages (AIP) module with a hybrid stacked glass-compound wafer level fan-out process was presented. Heterogeneous radio frequency (RF) chips were integrated into one single module with a microscale fan-out process. This paper aims to find a new strategy for 5G communication with 3D integration of multi-function chips.

Design/methodology/approach

The AIP module was composed of two stacked layers: the antenna layer and RF layer. After architecture design and performance simulation, the module was fabricated, The 8 × 8 antenna array was lithography patterned on the 12 inch glass wafer to reduce the parasitic parameters effect, and the signal feeding interface was fabricated on the backside of the glass substrate.

Findings

AIP module demonstrates a size of 180 mm × 180mm × 1mm, and its function covers the complete RF front-end chain from the antenna to signal to process and can be applied in 5 G communication and automotive components.

Originality/value

With three RF multi-function chips and two through silicon via (TSV) chips were embedded in the 12 inch compound wafer through the fan-out packaging process; two layers were interconnected with TSV and re-distributed layers.

Details

Microelectronics International, vol. 40 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

Article
Publication date: 22 August 2023

Zhe Li, Xinrui Liu and Bo Wang

Accounting scandals and earnings management problems at large firms such as Global Crossing and Enron have resulted in lots of wealth loss not only to corporate investors but also…

Abstract

Purpose

Accounting scandals and earnings management problems at large firms such as Global Crossing and Enron have resulted in lots of wealth loss not only to corporate investors but also led tremendous damage to societies. Hence, policymakers and academic researchers have started to explore mechanisms to prevent improprieties in financial reporting and further enhance firm value. Using data from United States (US)-listed companies between 2000 and 2018, this article explores the effect of ex-military executives on earnings quality, the role of financial analysts in their interplay and the firm value implication of earnings quality driven by ex-military executives.

Design/methodology/approach

This study employs a firm fixed-effects model to validate the main conjecture and adopts the weighted least squares, Granger causality analysis, instrumental variable approach, propensity score matching, entropy balancing approach and dynamic system Generalized Method of Moments (GMM) estimator to address robustness and endogeneity issues.

Findings

Authors reveal that companies run by ex-military senior executives exhibit lower levels of accruals-based and real earnings management than those without. The effect of management military leadership on constraining earnings management is more prominent for companies with low analyst coverage, suggesting that the military experience of executives could be a substitute for external monitoring. Authors also find that these ethical managers alleviate the negative impact of earnings management on firm value and that companies managed by these managers exhibit higher firm performance.

Practical implications

This study highlights the importance of the intrinsic motivation behind the effect of military experience on senior managers' personalities and offers essential stakeholder-related implications regarding the effect of military experience. The military experience of senior managers helps facilitate the attainment of broader corporate governance and economic objectives.

Originality/value

This article adds new insights to the literature on the role of managerial military experience in decision-making processes, financial reporting outcomes and firm performance by employing the upper echelons and imprinting theoretical perspectives.

Details

Journal of Accounting Literature, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0737-4607

Keywords

Article
Publication date: 12 September 2023

Shuwen Sun, Chenyu Song, Bo Wang and Haiming Huang

The safety performance of cooperative robots is particularly important. This paper aims to study collision detection and response of cooperative robots, which meet the lightweight…

Abstract

Purpose

The safety performance of cooperative robots is particularly important. This paper aims to study collision detection and response of cooperative robots, which meet the lightweight requirements of cooperative robots and help to ensure the safety of humans and robots.

Design/methodology/approach

This paper proposes a collision detection, recognition and response method based on dynamic models. First, this paper identifies the dynamic model of the robot. Second, an external torque observer is established based on the model, and a dynamic threshold collision detection method is designed to reduce the interference of model uncertainty on collision detection. Finally, a collision position and direction estimation method is designed, and a robot collision response strategy is proposed to reduce the harm caused by collisions to humans.

Findings

Comparative experiments are conducted on static threshold and dynamic threshold collision detection, and the results showed that the static threshold only detected one collision while the dynamic threshold could detect all collisions. Conducting collision position and direction estimation and collision response experiments, and the results show that this method can determine the location and direction of collision occurrence, and enable the robot to achieve collision separation.

Originality/value

This paper designs a dynamic threshold collision detection method that does not require external sensors. Compared with static threshold collision detection methods, this method can significantly improve the sensitivity of collision detection. This paper also proposes a collision position direction estimation method and collision separation response strategy, which can enable robots to achieve post collision separation and improve the safety of cooperative robots.

Details

Industrial Robot: the international journal of robotics research and application, vol. 50 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

Article
Publication date: 1 May 2019

Bo Wang, Yanhua Zhang, Haiyan Tan and Jiyou Gu

The purpose of the study was to prepare melamine-urea-formaldehyde (MUF) resin that would be resistant to boiling water and high temperature and exhibit low formaldehyde emission.

Abstract

Purpose

The purpose of the study was to prepare melamine-urea-formaldehyde (MUF) resin that would be resistant to boiling water and high temperature and exhibit low formaldehyde emission.

Design/methodology/approach

The authors prepared MUF resin with different F/(M + U) and changed the amount of melamine added, through the analysis of MUF resin properties to get the best reaction parameters, and used different amino acid cure systems including NH4Cl cured the resin.

Findings

Resin’s heat resistance and water resistance are mainly determined by the amount of melamine added, and formaldehyde emission of the plywood can be changed by adjusting F/(M + U). The peak temperature of the curing agent-cured resin increases as compared with the self-curing resin. Stronger the acidity of curing agent, faster the viscosity increased in probation period and lower the bonding strength and heat resistance of the resin.

Research limitations/implications

Melamine improves the heat resistance and water resistance of the resin. When the amount of melamine is more than a certain value, water resistance of the resin decreased.

Practical implications

MUF resin that is resistant to boiling water and exhibits low formaldehyde emission can be used in high temperature, high humidity and strict formaldehyde emission environment and can also be combined with other materials.

Social implications

It was helpful to reduce the effect of formaldehyde emission on people’s health and environmental pollution and is also beneficial for the expansion of the application range of aldehyde resin.

Originality/value

The originality is twofold: the influence of the acid strength of curing agent on the bonding strength of the resin adhesive and the method for preparing high performance MUF resin by following the traditional process.

Details

Pigment & Resin Technology, vol. 48 no. 3
Type: Research Article
ISSN: 0369-9420

Keywords

Open Access
Article
Publication date: 24 June 2021

Bo Wang, Guanwei Wang, Youwei Wang, Zhengzheng Lou, Shizhe Hu and Yangdong Ye

Vehicle fault diagnosis is a key factor in ensuring the safe and efficient operation of the railway system. Due to the numerous vehicle categories and different fault mechanisms…

Abstract

Purpose

Vehicle fault diagnosis is a key factor in ensuring the safe and efficient operation of the railway system. Due to the numerous vehicle categories and different fault mechanisms, there is an unbalanced fault category problem. Most of the current methods to solve this problem have complex algorithm structures, low efficiency and require prior knowledge. This study aims to propose a new method which has a simple structure and does not require any prior knowledge to achieve a fast diagnosis of unbalanced vehicle faults.

Design/methodology/approach

This study proposes a novel K-means with feature learning based on the feature learning K-means-improved cluster-centers selection (FKM-ICS) method, which includes the ICS and the FKM. Specifically, this study defines cluster centers approximation to select the initialized cluster centers in the ICS. This study uses improved term frequency-inverse document frequency to measure and adjust the feature word weights in each cluster, retaining the top τ feature words with the highest weight in each cluster and perform the clustering process again in the FKM. With the FKM-ICS method, clustering performance for unbalanced vehicle fault diagnosis can be significantly enhanced.

Findings

This study finds that the FKM-ICS can achieve a fast diagnosis of vehicle faults on the vehicle fault text (VFT) data set from a railway station in the 2017 (VFT) data set. The experimental results on VFT indicate the proposed method in this paper, outperforms several state-of-the-art methods.

Originality/value

This is the first effort to address the vehicle fault diagnostic problem and the proposed method performs effectively and efficiently. The ICS enables the FKM-ICS method to exclude the effect of outliers, solves the disadvantages of the fault text data contained a certain amount of noisy data, which effectively enhanced the method stability. The FKM enhances the distribution of feature words that discriminate between different fault categories and reduces the number of feature words to make the FKM-ICS method faster and better cluster for unbalanced vehicle fault diagnostic.

Details

Smart and Resilient Transportation, vol. 3 no. 2
Type: Research Article
ISSN: 2632-0487

Keywords

Article
Publication date: 3 May 2023

Xiao Wang, Xuan Liang, Bo Wang, Chang-qing Guo, Shan-gui Zhang, Kai Yang, Shi-ya Shao, Yan Sun, Zheng Guo, Xue-yan Yu, Donghai Zhang, Tai-jiang Gui, Wei Lu, Ming-liang Sun and Rui Ding

The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty…

Abstract

Purpose

The purpose of this study is to evaluate the effect of graphene, basalt flakes and their synergy on the corrosion resistance of zinc-rich coatings. As the important heavy-duty anticorrosion coatings, zinc-rich coatings provided cathodic protection for the substrate. However, to ensure cathodic protection, a large number of zinc powder made the penetration resistance known as the weakness of zinc-rich coatings. Therefore, graphene and basalt flakes were introduced into zinc-rich coatings to coordinate its cathodic protection and shielding performance.

Design/methodology/approach

Three kinds of coatings were prepared; they were graphene modified zinc-rich coatings, basalt flakes modified zinc-rich coatings and graphene-basalt flakes modified zinc-rich coatings. The anticorrosion behavior of painted steel was studied by using the electrochemical impedance spectroscopy (EIS) technique in chloride solutions. The equivalent circuit methods were used for EIS analysis to obtain the electrode process structure of the coated steel system. Simultaneously, the corrosion resistance of the three coatings was evaluated by water resistance test, salt water resistance test and salt spray test.

Findings

The study found that the addition of a small amount of graphene and basalt flakes significantly improved the anticorrosion performance of coatings by enhancing their shielding ability against corrosive media and increasing the resistance of the electrochemical reaction. The modified coatings exhibited higher water resistance, salt water resistance and salt spray resistance. The graphene-basalt flakes modified zinc-rich coatings demonstrated the best anticorrosion effect. The presence of basalt scales and graphene oxide in the coatings significantly reduced the water content and slowed down the water penetration rate in the coatings, thus prolonging the coating life and improving anticorrosion effects. The modification of zinc-rich coatings with graphene and basalt flakes improved the utilization rate of zinc powder and the shielding property of coatings against corrosive media, thus strengthening the protective effect on steel structures and prolonging the service life of anticorrosion coatings.

Originality/value

The significance of developing graphene-basalt flakes modified zinc-rich coatings lies in their potential to offer superior performance in corrosive environments, leading to prolonged service life of metallic structures, reduced maintenance costs and a safer working environment. Furthermore, such coatings can be used in various industrial applications, including bridges, pipelines and offshore structures, among others.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 8 July 2022

Lei Huang, Qiushi Xia, Tianhe Gao, Bo Wang and Kuo Tian

The purpose of this paper is to propose a numerical prediction method of buckling loads for shell structures under axial compression and thermal loads based on vibration…

Abstract

Purpose

The purpose of this paper is to propose a numerical prediction method of buckling loads for shell structures under axial compression and thermal loads based on vibration correlation technique (VCT).

Design/methodology/approach

VCT is a non-destructive test method, and the numerical realization of its experimental process can become a promising buckling load prediction method, namely numerical VCT (NVCT). First, the derivation of the VCT formula for thin-walled structures under combined axial compression and thermal loads is presented. Then, on the basis of typical NVCT, an adaptive step-size NVCT (AS-NVCT) calculation scheme based on an adaptive increment control strategy is proposed. Finally, according to the independence of repeated frequency analysis, a concurrent computing framework of AS-NVCT is established to improve efficiency.

Findings

Four analytical examples and one optimization example for imperfect conical-cylindrical shells are carried out. The buckling prediction results for AS-NVCT agree well with the test results, and the efficiency is significantly higher than that of typical numerical buckling methods.

Originality/value

The derivation of the VCT formula for thin-walled shells provides a theoretical basis for NVCT. The adaptive incremental control strategy realizes the adaptive adjustment of the loading step size and the maximum applied load of NVCT with Python script, thus establishing AS-NVCT.

Details

Multidiscipline Modeling in Materials and Structures, vol. 18 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 1 October 2019

Yangong Wu, Zheng Qiao, Jiadai Xue, Yutao Liu and Bo Wang

The purpose of this paper is to present a novel numerical approach to analyze the static performance of aerostatic thrust bearings by adopting a general finite element method…

Abstract

Purpose

The purpose of this paper is to present a novel numerical approach to analyze the static performance of aerostatic thrust bearings by adopting a general finite element method calculation program.

Design/methodology/approach

The characteristics of a gas film are described by the Reynolds equation and the pressure distribution is solved using the finite element method. A root iterative method is proposed to meet the requirement of the mass-conservation law because multiple pocketed orifice-type restrictors are treated as a series of special boundary conditions.

Findings

The static performance of a rotary table using aerostatic thrust bearings, including load carrying capacity and stiffness, can be predicted by the method; moreover, it can be further confirmed through experiments on the designed rotary table.

Originality/value

The method combining the finite element and root iterative methods is highly accurate and has a low time-cost for analyzing aerostatic thrust bearings with multiple pocketed orifice-type restrictors.

Details

Industrial Lubrication and Tribology, vol. 72 no. 1
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 24 November 2023

Bo Wang, Kangyin Dong and Farhad Taghizadeh-Hesary

China is a significant energy consumer with increasingly severe resource constraints and environmental problems, requiring low-carbon energy transformation and encouraging…

Abstract

Purpose

China is a significant energy consumer with increasingly severe resource constraints and environmental problems, requiring low-carbon energy transformation and encouraging high-quality energy development (HED). Green finance significantly affects the effect on HED as a cutting-edge financial strategy to support environmental improvement and encourage green development.

Design/methodology/approach

Using panel data from 30 provinces from 2007 to 2019 and the system-generalized method of moments method, this paper investigates the impact of green finance on HED, and further explores their threshold effect, heterogeneous and asymmetry analysis.

Findings

The main results indicate that: (1) green finance positively affects HED in China; in other words, a 1% increase in the green finance index will boost HED by an average of 0.767%; (2) as the economy improves, the positive impact of green finance on HED will be even more significant and (3) the contribution of green finance to HED is more significant in the northern provinces and areas with lower HED levels.

Originality/value

This paper puts forward relevant policy suggestions to further improve the construction of the green financial system.

Details

The Journal of Risk Finance, vol. 25 no. 1
Type: Research Article
ISSN: 1526-5943

Keywords

Article
Publication date: 7 August 2023

Bo Wang and Tingting Xie

According to construal level theory, close (versus far) psychological distance is associated with low (versus high) construal level. Despite the evidence for discount frame…

Abstract

Purpose

According to construal level theory, close (versus far) psychological distance is associated with low (versus high) construal level. Despite the evidence for discount frame effect, it is unclear whether psychological distance and product nature play moderating roles. In addition, little has been known whether the effect of discount frame can extend to other dependent variables such as willingness to pay (WTP). Driven by construal level theory, five experiments were conducted to explore whether the effect of discount frame is dependent on psychological distance and product nature (i.e. utilitarian versus hedonic product).

Design/methodology/approach

The experimental method was used, with discount frame, psychological distance and product type as the independent variables and purchase intention, attitude towards the advertisement, perceived value and WTP as the dependent variables. Participants were presented with promotion scenarios in which psychological distance and discount format were manipulated. In order to test the generalizability of results, promotional scenarios for both utilitarian (i.e. backpack bag and shampoo) and hedonic products (i.e. scenery ticket and perfume) were presented. Data were collected via the online experiment platform (i.e. www.Credamo.com).

Findings

The authors found an interaction between discount frame and spatial distance in that consumers had more positive attitude toward percent off than amount off under near-spatial distance. However, no interaction was observed between discount frame and temporal, social or hypothetical distance.

Originality/value

Taken together, the current study for the first time reveals that the effect of discount frame is contingent on a specific dimension of psychological distance (i.e. spatial distance), regardless of whether the product is utilitarian or hedonic. Findings from this study for the first time pose a challenge to the notion that construal-level match necessarily leads to more favorable consumer responses, suggesting that there may be a unique mechanism underlying the joint effects of spatial distance and discount frame. The current findings can provide important implications for marketers and retailers in an effort to design effective promotional messages.

Details

Marketing Intelligence & Planning, vol. 41 no. 6
Type: Research Article
ISSN: 0263-4503

Keywords

1 – 10 of over 1000