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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 Transport, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2632-0487

Keywords

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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

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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

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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

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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

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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. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2040-8749

Keywords

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Article
Publication date: 2 August 2018

Bo Wang, Franca Giannini, Marina Monti, BaoJun Li, Ping Hu and JiCai Liang

This paper aims to automatically derive a 2D parametric model of the main characteristic lines of a car from images, blueprints or hand-made sketches of its side view…

Abstract

Purpose

This paper aims to automatically derive a 2D parametric model of the main characteristic lines of a car from images, blueprints or hand-made sketches of its side view. Then this model can be used for the further computer-aided design manipulation starting from images of the side view of a car.

Design/methodology/approach

The method combines different image edge detection techniques and edge removal processes with optimization techniques according to local and global constraints specific of the single curves to automatically construct a precise parametric model of the main character lines of a car from images. First, process the car image to compute the most important curves and then warp a car template model to match its feature points and curves with the ones detected in the image.

Findings

The paper provides method to construct parametric model from an image using maximum cover ratio to the edge points obtained by state-of-the-art edge detection algorithms. A feature points’ organization mechanism produces quadric curves to express feature curves of a product.

Research limitations/implications

The robustness of the presented method depends on the completeness of edge detection results and the accuracy of some key points’ registration result, so if the image is not good, the result cannot be trusted. Only side-view is considered in this paper. Additional limits in the process regard the side view verification: pictures of the front or rear view can be wrongly classified as lateral ones when they contain round lights.

Practical implications

This program enables designers to convert the image to geometric parametric model directly.

Originality/value

The method is applicable to shaded pictures, sketches and blue prints of the side view of a car. It can process a database of car images in a batch mode or a specific picture on user demand. The method classifies the cars to different categories: SUV/Wagon/Hatchback, sedan, city and coupe. The authors obtain good results for every category.

Details

Engineering Computations, vol. 35 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

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Book part
Publication date: 8 August 2017

Anna Zakharzhevskaya

This paper examines diverging views on the Chongqing model, the policy experiment led by Bo Xilai from 2007 to 2012 that was famous for its “red songs” and the campaign…

Abstract

This paper examines diverging views on the Chongqing model, the policy experiment led by Bo Xilai from 2007 to 2012 that was famous for its “red songs” and the campaign against organized crime. It has impressed both the supporters of socialist identity of China and the supporters of liberal identity and led to an intense debate concerning China’s path of development. This paper attempts to discuss and clarify to what extent the Chongqing model represented a genuine socialist experiment and the implications of the model for China’s future.

Details

Return of Marxian Macro-Dynamics in East Asia
Type: Book
ISBN: 978-1-78714-477-4

Keywords

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Article
Publication date: 4 April 2016

Fowei Wang, Bo Shen, Shaoyuan Sun and Zidong Wang

The purpose of this paper is to improve the accuracy of the facial expression recognition by using genetic algorithm (GA) with an appropriate fitness evaluation function…

Abstract

Purpose

The purpose of this paper is to improve the accuracy of the facial expression recognition by using genetic algorithm (GA) with an appropriate fitness evaluation function and Pareto optimization model with two new objective functions.

Design/methodology/approach

To achieve facial expression recognition with high accuracy, the Haar-like features representation approach and the bilateral filter are first used to preprocess the facial image. Second, the uniform local Gabor binary patterns are used to extract the facial feature so as to reduce the feature dimension. Third, an improved GA and Pareto optimization approach are used to select the optimal significant features. Fourth, the random forest classifier is chosen to achieve the feature classification. Subsequently, some comparative experiments are implemented. Finally, the conclusion is drawn and some future research topics are pointed out.

Findings

The experiment results show that the proposed facial expression recognition algorithm outperforms ones in the existing literature in terms of both the actuary and computational time.

Originality/value

The GA and Pareto optimization algorithm are combined to select the optimal significant feature. To improve the accuracy of the facial expression recognition, the GA is improved by adjusting an appropriate fitness evaluation function, and a new Pareto optimization model is proposed that contains two objective functions indicating the achievements in minimizing within-class variations and in maximizing between-class variations.

Details

Assembly Automation, vol. 36 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

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Article
Publication date: 8 August 2016

Xiaoli Kong, Bo Zhou, Jixiao Wang and Wenping Li

The purpose of this paper is to study the engineering application of diamond like carbon (DLC) coatings on the surfaces of piston pins and bucket tappets for a 2.0 L…

Abstract

Purpose

The purpose of this paper is to study the engineering application of diamond like carbon (DLC) coatings on the surfaces of piston pins and bucket tappets for a 2.0 L supercharged gasoline engine. The friction loss and durability of DLC-coated components were investigated.

Design/methodology/approach

The tribological characteristics were examined under oil-lubricated conditions in a CETR UMT reciprocating tribometer. In a motored engine test rig, friction loss torque test was performed to estimate the improvement in fuel economy. Fired engine durability bench tests of typical duration of 450 h were completed to access the durability and wear resistance of DLC coating. Before and after durability tests, coated and uncoated components were measured on the sliding surface by a profilometer technique.

Findings

Friction and wear test results show that DLC coating has low friction coefficient and reduces the wear rates by almost ten times compared to those of uncoated surfaces. Friction loss measurements indicate that DLC-coated tappets can reduce valve train friction loss by 29 per cent, and DLC-coated piston pins can reduce piston group friction by 11 per cent. Based on fired engine durability bench tests, it is evidenced that none of the coated tappets and pins show any noticeable peeling or delamination. Wear profiles analysis results indicate that DLC-coated engine components give rise to a substantial reduction in wear.

Originality/value

DLC coating applied onto the working surface of piston pin and bucket tappet can effectively reduce the friction loss of gasoline engine. DLC coating exhibits sufficient durability and improves friction and wear performance.

Details

Industrial Lubrication and Tribology, vol. 68 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

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