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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…

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. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1356-5362

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…

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: 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…

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: 21 June 2022

Bo Wang

This study examines whether the absolute number heuristic holds for consumers' responses to higher-priced versus lower-priced products. Further, it explores whether the…

Abstract

Purpose

This study examines whether the absolute number heuristic holds for consumers' responses to higher-priced versus lower-priced products. Further, it explores whether the different construal level as induced from presence or absence of a product image can be a boundary condition for the absolute number heuristic.

Design/methodology/approach

Four experiments were conducted. In Experiments 1 and 2, participants were presented with a discount either in the amount off or percent off format, for products whose prices were 99 Yuan, 100 Yuan and 101 Yuan, respectively. In Experiment 3, the prices were changed to be 90 Yuan, 900 Yuan and 9,000 Yuan, respectively. In Experiment 4, the prices were 48 Yuan and 480 Yuan, respectively.

Findings

Experiment 1 showed neither main effect of discount frame nor interaction between price level and discount frame for all dependent variables (i.e. willingness to pay or WTP, purchase intention, attitude and perceived value), thus posing a challenge to the absolute number heuristic. Notably, the lack of main effect and interaction for purchase intention, attitude and perceived value were replicated in Experiments 2, 3 and 4. With WTP being the dependent variable, however, Experiment 4 showed that the effect of discount frame was dependent on price level.

Research limitations/implications

The current findings pose a challenge to the absolute number heuristic and contribute to the literature by revealing that the joint effects of price level and discount frame can be moderated by whether an ad contains the product image.

Practical implications

It is necessary for marketers to realize that inclusion of a product image may eliminate the effect of discount frame. Specifically, in terms of promoting a relatively expensive product, in order for the percent off discount to enhance the amount of money that consumers are willing to pay, an ad without a product image may be more favorable.

Originality/value

The current study is the first to challenge the absolute number heuristic by showing that the interaction between price level and discount frame is contingent on whether an ad contains the product image.

Details

Marketing Intelligence & Planning, vol. 40 no. 7
Type: Research Article
ISSN: 0263-4503

Keywords

Article
Publication date: 5 June 2017

Man He, Bo Wang, Weisheng Xia, Shijie Chen and Jinzhuan Zhu

The purpose of this paper is to study the microstructure and mechanical behaviour of smaller microbumps for high density solder interconnects.

Abstract

Purpose

The purpose of this paper is to study the microstructure and mechanical behaviour of smaller microbumps for high density solder interconnects.

Design/methodology/approach

The microstructure was analyzed by scanning electron microscopy and electron backscatter diffraction tests to determine the Sn grain number of the resultant microbumps. The nanomechanical properties of Sn microbumps were investigated by the nanoindentation and shearing tests to understand the failure mechanism and assess the reliability of ultra-high density solder interconnects with numbered grains.

Findings

Only one Sn grain is observed in the interconnect matrix when the microbumps are miniaturized to 40 μm or less. Because of the body-centred tetragonal lattice of ß-Sn unit cell, the mechanical properties of the one-grain Sn microbumps are remarkably anisotropic, which are proved by the difference of the elastic modulus and the stiffness in the different orientations. The shearing tests show that the one-grain Sn microbump has a typical brittle sliding fracture of monocrystal at different shearing speeds.

Practical implications

The paper provides a comparable study for the performance of the bigger solder joints and also makes preliminary research on the microstructure and mechanical behaviour of Sn microbumps with the diameter of 40 μm.

Originality/value

The findings in this paper provide methods of microstructure study by combination of EBSD test and metallographic analysis, mechanical study by combination of nanoindentation test and shearing test, which can provide good guidelines for other smaller microbumps. The strain rate sensitivity exponent of the one-grain Sn microbumps is consistent with the Pb-free bulk solder. This implies that the one-grain Sn microbump has a comparable flow stress to Sn37Pb solder, which is beneficial for Pb-free replacement in higher density microelectronic packaging.

Details

Soldering & Surface Mount Technology, vol. 29 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

Article
Publication date: 17 October 2018

Jingcheng Fu, Jun Huang, Li-Bo Wang and Lei Song

The purpose of this paper is to propose an identification method of acquiring aircraft mode characteristics based on fast Fourier transform and half-power bandwidth…

Abstract

Purpose

The purpose of this paper is to propose an identification method of acquiring aircraft mode characteristics based on fast Fourier transform and half-power bandwidth method, aiming at the common oscillation met in flight test.

Design/methodology/approach

The feasibility of this method is demonstrated through derivation; the robustness analysis is conducted through three examples, and finally the method was applied on a set of sideslip angle record from flight test.

Findings

The derivation and numerical analysis both show that the presented method can have high accuracy and good robustness under coupled mode and noise condition.

Practical implications

The method proposed is of robustness, and it is concise and easy to apply on flight data record.

Originality/value

This paper demonstrates the feasibility of half power bandwidth to be applied on oscillation mode characteristics identification from flight data record, which is different from other method applied.

Details

Aircraft Engineering and Aerospace Technology, vol. 91 no. 1
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 11 July 2022

Bo Wang

Although the evidence exists for the effect of promotional frame on repurchase intention, it is unclear whether the timing of repurchase can moderate the effect. In this…

Abstract

Purpose

Although the evidence exists for the effect of promotional frame on repurchase intention, it is unclear whether the timing of repurchase can moderate the effect. In this paper, three experiments were conducted to answer this question.

Design/methodology/approach

In Experiment 1, a 2 (framing: bundle vs. gift) × 2 (repurchase target: focal vs. supplementary) × 2 (timing: short vs. long) between-subjects design was used. In Experiment 2, an identical design was used except that repurchase target being the within-subjects factor. In Experiment 3, the design was based on that of Experiment 2 and brand was added a between-subjects factor.

Findings

Experiment 1 showed that, with a short interval, repurchase intention under gift frame was higher than that under bundle frame. With a long interval, there was no significant difference between the gift and bundle frames. Experiment 2, however, indicated no effects for expensive products. Experiment 3 showed that brand (private versus national brand) moderate the interaction between framing, repurchase target and timing. Particularly, for private brand, no significant comparisons were found; for national brand, repurchase intention for the focal product was significantly higher than for the supplementary product, but only under the conditions of long interval and gift frame (rather than bundle frame).

Originality/value

Taken together, findings from the current study contributes to the literature by showing for the first time that repurchase timing can moderate the promotional frame effect (i.e. higher repurchase intention under gift framing relative to bundle framing occurs in the short interval but not long interval) and that brand type can moderate the joint effects of framing, timing and repurchase target (i.e. national brand, rather than private brand, paired with long interval and gift frame results in higher repurchase intention for the focal product). The findings provide marketers with important knowledge in terms of how to adjust a promotional frame depending on when consumers repurchase a product and whether the product has a private or national brand.

Details

Marketing Intelligence & Planning, vol. 40 no. 8
Type: Research Article
ISSN: 0263-4503

Keywords

Article
Publication date: 15 September 2021

Bo Wang, Qiang Liang, Lihong Song and Erming Xu

With features of both “family” and “business,” family businesses must seek a balance between the emotional aspect of “family” and the economic aspect of “business” in its…

Abstract

Purpose

With features of both “family” and “business,” family businesses must seek a balance between the emotional aspect of “family” and the economic aspect of “business” in its organizational and decision-making processes to ensure the sustainability of the family’s entrepreneurship. This study aims to focus on how internal institutional complexity combined evolves alongside the growth of the family business.

Design/methodology/approach

The research looks, from the perspective of institutional logic, into the Charoen Pokphand Group, which is an epitome of overseas Chinese family businesses and proceeds to build a model of family business growth in the context of institutional complexity.

Findings

The research finds that as a family business grows, institutional complexity inside the organization would change from aligned period to sustaining period and then to dominant period. Then further elucidates the process of proactive response in different stages of the development of a family business. Attaching equal importance to the cultivation of entrepreneurship and to the continuation of family values and culture is the crucial mechanism by which Chinese family businesses seek a balance between family logic and business logic.

Originality/value

This paper unveils the change of institutional complexity in the evolution of family businesses and the process of action of its agency as an organization, and simultaneously partly reveals the features of entrepreneurship that overseas Chinese family businesses have as they grew, which is of positive significance for exploring and building a path of growth unique to Chinese family businesses.

Details

Nankai Business Review International, vol. 13 no. 1
Type: Research Article
ISSN: 2040-8749

Keywords

1 – 10 of over 1000