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Article
Publication date: 19 March 2021

Rongxing Duan, Shujuan Huang and Jiejun He

This paper aims to deal with the problems such as epistemic uncertainty, common cause failure (CCF) and dynamic fault behaviours that arise in complex systems and develop…

Abstract

Purpose

This paper aims to deal with the problems such as epistemic uncertainty, common cause failure (CCF) and dynamic fault behaviours that arise in complex systems and develop an effective fault diagnosis method to rapidly locate the fault when these systems fail.

Design/methodology/approach

First, a dynamic fault tree model is established to capture the dynamic failure behaviours and linguistic term sets are used to obtain the failure rate of components in complex systems to deal with the epistemic uncertainty. Second, a β factor model is used to construct a dynamic evidence network model to handle CCF and some parameters obtained by reliability analysis are used to build the fault diagnosis decision table. Finally, an improved Vlsekriterijumska Optimizacija I Kompromisno Resenje algorithm is developed to obtain the optimal diagnosis sequence, which can locate the fault quickly, reduce the maintenance cost and improve the diagnosis efficiency.

Findings

In this paper, a new optimal fault diagnosis strategy of complex systems considering CCF under epistemic uncertainty is presented based on reliability analysis. Dynamic evidence network is easy to carry out the quantitative analysis of dynamic fault tree. The proposed diagnosis algorithm can determine the optimal fault diagnosis sequence of complex systems and prove that CCF should not be ignored in fault diagnosis.

Originality/value

The proposed method combines the reliability theory with multiple attribute decision-making methods to improve the diagnosis efficiency.

Details

Engineering Computations, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 10 January 2020

Yining Zeng, Rongxing Duan, Shujuan Huang and Tao Feng

This paper aims to deal with the problems of failure dependence and common cause failure (CCF) that arise in reliability analysis of complex systems.

Abstract

Purpose

This paper aims to deal with the problems of failure dependence and common cause failure (CCF) that arise in reliability analysis of complex systems.

Design/methodology/approach

Firstly, a dynamic fault tree (DFT) is used to capture the dynamic failure behaviours and converted into an equivalent generalized stochastic petri net (GSPN) for quantitative analysis. Secondly, an efficient decomposition and aggregation (EDA) theory is combined with GSPN to deal with the CCF problem, which exists in redundant systems. Finally, Birnbaum importance measure (BIM) is calculated based on the EDA approach and GSPN model, and it is used to take decisions for system improvement and fault diagnosis.

Findings

In this paper, a new reliability evaluation method for dynamic systems subject to CCF is presented based on the DFT analysis and the GSPN model. The GSPN model is easy to capture dynamic failure behaviours of complex systems, and the movement of tokens in the GSPN model represent the changes in the state of the systems. The proposed method takes advantage of the GSPN model and incorporates the EDA method into the GSPN, which simplifies the reliability analysis process. Meanwhile, simulation results under different conditions show that CCF has made a considerable impact on reliability analysis for complex systems, which indicates that the CCF should not be ignored in reliability analysis.

Originality/value

The proposed method combines the EDA theory with the GSPN model to improve the efficiency of the reliability analysis.

Details

Engineering Computations, vol. 37 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 27 November 2018

Cunfu Yan, Shujuan Li, Leipeng Yang and Longfei He

The purpose of this paper is to investigate the effects of parameters on the liquid phase migration (LPM) during the freeze-form extrusion fabrication (FEF) process.

Abstract

Purpose

The purpose of this paper is to investigate the effects of parameters on the liquid phase migration (LPM) during the freeze-form extrusion fabrication (FEF) process.

Design/methodology/approach

To carry out this study, three factors were systematically investigated using orthogonal design of experiments. These three parameters are the extrusion velocity, the extrusion interval time and the extrusion head length. An orthogonal array with nine test units was selected for the experiments. Range analysis and analysis of variance were used to analyze the data obtained by the orthogonal experiments to identify the order of significant factors on LPM.

Findings

It was found that the LPM decreased with the increase of extrusion velocity and increased with the lengthening of extrusion interval time and the length of the extrusion nozzle. The order of significant factors for the LPM were found to be extrusion velocity > extrusion nozzle length > extrusion interval time.

Practical implications

Using an orthogonal design of experiments and a statistical analysis method, the liquid content of extrudate can be predicted and appropriate process parameter values can be selected. This leads to the minimization of LPM during the FEF process. Also, this analysis method could be used to study the LPM in other paste extrusion processes.

Originality/value

This paper suggests that the factors have significant impact on LPM during FEF process. The following analysis in this paper is useful for FEF users when prediction of LPM is needed. This methodology could be easily applied to different materials and initial conditions for optimization of other FEF-type processes. The research can also help to get better understanding of LPM during the FEF process.

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Article
Publication date: 26 August 2014

Zhifeng Huang, Xiaoyang Ma, Zemin Qiao, Shujuan Wang and Xinli Jing

This paper aims to disclose the evolution of pendulum hardness of two-component acrylic polyurethane coatings during the cure process and attempts to describe the…

Abstract

Purpose

This paper aims to disclose the evolution of pendulum hardness of two-component acrylic polyurethane coatings during the cure process and attempts to describe the quantitative relationship between pendulum hardness and curing time. These findings are helpful for the study of fast curing acrylic polyurethane coatings.

Design/methodology/approach

The pendulum hardness method was used to monitor the hardness of two-component acrylic polyurethane coatings during curing. The quantitative relationship between pendulum hardness and curing time can be obtained with Avrami equation.

Findings

The evolution of coating pendulum hardness can be divided into three stages. By using the Avrami equation that explained the influence of both the acid value and the curing temperature on the drying speed of hydroxyl acrylic resin, the evolution of coating pendulum hardness during curing can also be accurately described.

Research limitations/implications

It should be noted that the physical meaning of the Avrami exponent, n, is not yet clear.

Practical implications

The results are of great significance for the development of fast-curing hydroxyl-functional acrylic resins, with the potential to improve the drying speed of the coatings used in automotive refinish.

Originality/value

It is novel to divide the pendulum hardness into three stages, and, for the first time, the Avrami equation is utilized to describe the evolution of coating pendulum hardness during curing.

Details

Pigment & Resin Technology, vol. 43 no. 5
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 4 April 2016

Yang Lu, Shujuan Yi, Yurong Liu and Yuling Ji

This paper aims to design a multi-layer convolutional neural network (CNN) to solve biomimetic robot path planning problem.

Abstract

Purpose

This paper aims to design a multi-layer convolutional neural network (CNN) to solve biomimetic robot path planning problem.

Design/methodology/approach

At first, the convolution kernel with different scales can be obtained by using the sparse auto encoder training algorithm; the parameter of the hidden layer is a series of convolutional kernel, and the authors use these kernels to extract first-layer features. Then, the authors get the second-layer features through the max-pooling operators, which improve the invariance of the features. Finally, the authors use fully connected layers of neural networks to accomplish the path planning task.

Findings

The NAO biomimetic robot respond quickly and correctly to the dynamic environment. The simulation experiments show that the deep neural network outperforms in dynamic and static environment than the conventional method.

Originality/value

A new method of deep learning based biomimetic robot path planning is proposed. The authors designed a multi-layer CNN which includes max-pooling layer and convolutional kernel. Then, the first and second layers features can be extracted by these kernels. Finally, the authors use the sparse auto encoder training algorithm to train the CNN so as to accomplish the path planning task of NAO robot.

Details

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

Keywords

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Article
Publication date: 7 August 2017

Xin Liang, Lin Xiu, Sibin Wu and Shujuan Zhang

Private firms in China are like the third child in a family, constantly struggling to establish their position in an environment favoring their state-owned and collective…

Abstract

Purpose

Private firms in China are like the third child in a family, constantly struggling to establish their position in an environment favoring their state-owned and collective siblings. The purpose of this paper is to discover some long-term-oriented legitimacy building strategies for private firms in China.

Design/methodology/approach

This paper examines the effect of both internal and external institutional factors on long-term legitimacy for private enterprises. The authors integrate stakeholder perspective and institutional theory to provide a framework of building sustainable legitimacy.

Findings

The authors’ framework delineates that a private company can build sustainable legitimacy through catering long-term legitimacy conferring to constituents such as customers, social responsibility and patriotism in the external institutional environment.

Practical implications

The authors’ framework further indicates how private firms could leverage internal institutional environment through developing appropriate mission, culture, leadership and human resources practices in conformity to the demands of constituents for gaining long-term legitimacy.

Originality/value

This paper is the first to address the short-term nature of legitimacy building strategies proposed in the past literature. In addition, it is also the first attempt to explore the multiplicity in legitimacy in China in search of long-term legitimacy building approaches.

Details

Chinese Management Studies, vol. 11 no. 3
Type: Research Article
ISSN: 1750-614X

Keywords

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Article
Publication date: 5 December 2016

David O. Obada, Muhammad Dauda, Fatai O. Anafi, Abdulkarim S. Ahmed and Olusegun A. Ajayi

A structural and textural characterization study has been performed to investigate the adherence of zeolite-based catalyst washcoated onto honey-comb-type cordierite…

Abstract

Purpose

A structural and textural characterization study has been performed to investigate the adherence of zeolite-based catalyst washcoated onto honey-comb-type cordierite monoliths. The supports were characterized by the scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDS), X-ray diffraction (XRD) and Brunauer–Emmett–Teller (BET) techniques.

Design/methodology/approach

SEM/EDS provided quantitative estimate of the washcoated monolith as the elemental composition of catalyst coating. The XRD pattern deduced that the zeolite-based catalysts were successfully mounted on the cordierite support, showing the characteristic peaks of zeolites (Zeolite Socony Mobil–5; ZSM-5) at Braggs angles of 7.88°, 8.76°, 23.04°, 23.88° and 24.36°, whereas the characteristic peak of cordierite is seen at a Braggs angle of 10.44°.

Findings

The BET results proved that a monolayer of zeolite may serve the need for surface area and porosity. This was evident in the increase of surface area of washcoated support as against the bare support. The obtained isotherms were of Type IV, illustrating the presence of mesopores. The adsorption and desorption isotherm branches coincided over the interval 0 < P/P0 < 0.50 and 0 < P/P0 < 0.45, showing N2 reversible adsorption for the two samples, respectively.

Originality/value

It was concluded that the composite materials which are ZSM-5 (Si/Al = 25) and precursors of the transition salts of copper, zinc and ceria powders were deposited on the catalyst supports, establishing the success of the coating procedure relative to the adherence of the catalyst compositions on the ceramic support.

Details

World Journal of Engineering, vol. 13 no. 6
Type: Research Article
ISSN: 1708-5284

Keywords

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