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Article
Publication date: 25 September 2018

Hui Zhao, Shengnan Li, Hongyu Yang and Quan Zhou

Variable fractional delay filtering is an important technology in signal processing; the research shows that all-pass variable fractional delay (VFD) filters achieve…

Abstract

Purpose

Variable fractional delay filtering is an important technology in signal processing; the research shows that all-pass variable fractional delay (VFD) filters achieve higher design accuracy than FIR VFD filters; therefore, the design, analysis and implementation of all-pass VFD filters are of great importance.

Design/methodology/approach

In this paper, a two-stage approach for the design of general 1-D stable VFD all-pass filters is proposed. The method takes the desired group delay range [N−1, N], where N is the filter order.

Findings

The design algorithm is decomposed into two design stages: first, a set of fixed delay all-pass filters are designed by minimizing a set of objective functions defined in terms of approximating error criterion and filter stability constraint. Then, the design result is determined by fitting each of the fixed delay all-pass filter coefficients as 1-D polynomials. A design example together with its comparisons with those of the recent literature studies is given to justify the effectiveness of the proposed design method.

Originality/value

An illustrating design example shows that the method proposed can achieve better filter performances than the existing ones.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 37 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

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Article
Publication date: 3 July 2018

Hui Zhao

The purpose of this paper is to investigate how the Chinese government generates authority during a crisis through discursive practices expressed in social media.

Abstract

Purpose

The purpose of this paper is to investigate how the Chinese government generates authority during a crisis through discursive practices expressed in social media.

Design/methodology/approach

Using the theoretical framework of authority and the method of genre analysis, this study examined the top 100 forwarded posts on Weibo about a high-profile murder to determine the mechanisms involved in generating authority.

Findings

This study provides empirical support that building and maintaining authority distinguishes governments from other social actors during crisis communication. The genre analysis demonstrates that the strategic use of genre chain and genre mixing contributes to the construction of governments’ authority during a crisis. Furthermore, this study suggests the performative and social constructionist approach to understand governments’ authority in the digital age on two levels: a situationally-constructed concept that goes beyond the context of fixed institutions and a relationally-constructed concept that is promoted through discursive collaboration among various social actors.

Research limitations/implications

This study does not directly assess the effectiveness of a government’s ability to construct its authority. Nor does it examine the construction of governments’ authority outside the context of an authoritarian regime. These issues should be addressed in future research.

Practical implications

This study offers governmental organizations some practical insights that can be used to infuse a constructive aspect of authority into their crisis communication plans, practices and processes.

Originality/value

Here, authority is seen as a social construction that foregrounds the discursive, performative, constructive and communicative dimensions of crisis communication. Moreover, this study points to the need for a more complex integrated perspective in crisis communication that includes and connects corporate and government crisis communication.

Details

Journal of Communication Management, vol. 22 no. 3
Type: Research Article
ISSN: 1363-254X

Keywords

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Article
Publication date: 12 July 2021

Yufei Chen, Hui Zhao, Yulong Liu and Hongyue CHU

Bismaleimide (BMI) is a kind of thermosetting resin and its application is usually limited by low toughness. In this paper, two kinds of reinforcement intercalator…

Abstract

Purpose

Bismaleimide (BMI) is a kind of thermosetting resin and its application is usually limited by low toughness. In this paper, two kinds of reinforcement intercalator amino-terminated polyoxypropylene (POP) and octadecyl trimethyl ammonium chloride (OTAC) were designed and synthesized to toughen BMI resin and the toughening effect was compared and analyzed. The purpose of this paper is to toughen BMI resin and analyze the toughening effect of two reinforcements intercalator amino-terminated polyoxypropylene (POP) and octadecyl trimethyl ammonium chloride (OTAC).

Design/methodology/approach

Sodium-based montmorillonite (Na-MMT) was modified by POP and OTAC, and the ion-exchange reaction obtained organic montmorillonite (POP-MMT and OTAC-MMT). The polymer matrix (MBAE) was synthesized, in which 4,4’-diamino diphenyl methane BMI was used as the monomer and 3,3’-diallyl bisphenol A and bisphenol A diallyl ether were used as active diluents. And then, POP-MMT/MBAE and OTAC-MMT/MBAE composites were prepared using MBAE as matrix and POP-MMT or OTAC-MMT as reinforcement. The Fourier-transform infrared, X-ray diffraction and scanning electron microscope (SEM) of the filler and microstructure and mechanical properties of the composite were characterized to the better reinforcement.

Findings

POP-MMT and OTAC-MMT enhanced BMI-cured products’ toughness by generating microcracks in the polymer to absorb more fracture energy. Meanwhile, POP-MMT and OTAC-MMT were the main stress components and the enhancement of the interface interaction was beneficial to transfer the external force from the matrix to the reinforcement and improved the mechanical properties of the composite. Furthermore, with the intercalation rate increasing, the compatibility of the two phases was increased and the performance of MBAE was also elevated.

Research limitations/implications

BMI is generally used as aerospace structural materials, functional materials, impregnating paint and other fields. However, high crosslinking density leads to moulding material’s brittleness and limits a wider range of applications. Therefore, it has become an urgent priority to explore and improve the mechanical properties of BMI resin.

Originality/value

POP and OTAC have successfully intercalated Na-MMT layers to get POP-MMT and OTAC-MMT, and the interplanar crystal spacing and the intercalation rate were calculated, respectively. The results were corresponding with the SEM images of POP-MMT and OTAC-MMT. After that, the morphology of composites illustrated the compatibility was related to the intercalation rate. According to the mechanism of modified MMT toughening epoxy resin, when they were dispersed uniformly in the matrix, the composite’s mechanical properties had been significantly improved. Additionally, OTAC-MMT with a higher intercalation rate had better compatibility and interfacial force with the matrix, so that the mechanical properties of OTAC-MMT/MBAE were the best.

Details

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

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Article
Publication date: 20 October 2020

Ruipeng Tong, Hui Zhao, Na Zhang, Hongwei Li, Xiaolong Wang and Hongqing Yang

The purpose of this study is to establish a modified accident causation model for highway construction accidents (ACM-HC) and describe the establishment process of the ACM-HC.

Abstract

Purpose

The purpose of this study is to establish a modified accident causation model for highway construction accidents (ACM-HC) and describe the establishment process of the ACM-HC.

Design/methodology/approach

Based on the 2–4 Model, a framework of the ACM-HC was constructed, and the accident causal factors (CF) were extracted from four aspects of human, material, environment and management. In addition, association rule mining (ARM) was introduced to analyze accident investigation reports to obtain the interrelationships between the factors. Based on the framework, factors and ARM results, the ACM-HC was established. Finally, the ACM-HC was verified with a tunnel collapse accident.

Findings

Both the external and internal causes of contractor cause accidents. The flaws of safety management of other stakeholders are external causes. In terms of the internal causes, there are four stages: direct causes, indirect causes, radical causes and root causes. More specifically, the direct causes refer to the unsafe acts and the unsafe conditions; ineffective safety supervision and poor individual factors of frontline workers constitute the indirect causes; the radical causes lie in the flaws of construction procedures and technical schemes; the root causes are related to the poor individual factors of decision makers and managers.

Originality/value

The ACM-HC expresses the causes, sequence and mechanism of highway construction accidents in a visual way. In addition, this study describes a process of using a qualitative–quantitative hybrid approach to establish a modified ACM, which provides a different perspective for the establishment of an ACM.

Details

Engineering, Construction and Architectural Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0969-9988

Keywords

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Article
Publication date: 25 January 2021

Lin Xue, Qiang Miao, Wenping Liang, Hui Zhao, Weiwei Shi, Shiwei Zuo and Hanchun Ma

The purpose of this paper is to prepare Ti(C,N) coatings on TA15 treated and not treated by shot peening using double glow plasma alloying technique. The effect of shot…

Abstract

Purpose

The purpose of this paper is to prepare Ti(C,N) coatings on TA15 treated and not treated by shot peening using double glow plasma alloying technique. The effect of shot peening on the wear behavior of Ti(C,N) coatings is discussed.

Design/methodology/approach

The Ti(C,N) coatings were prepared by double glow plasma alloying technique on two different TA15 substrate; one is shot peened and the other is not.

Findings

Ti(C,N) coating on SP-treated TA15 was thicker and denser, and the grain size was smaller compared with that on original TA15. Compared with the Ti(C,N) coating on original TA15, the wear resistance of that on SP-treated TA15 is improved. Ti(C,N) coating on SP-treated TA15 showed higher nanohardness and bearing capacity than that on original TA15.

Originality/value

For double glow plasma alloying technique, surface quality, surface activity and other factors will have influence on the thickness and density of the coating. The wear mechanisms of Ti(C,N) coating on original TA15 are serious abrasive wear and oxidation wear. However, the wear mechanism of Ti(C,N) coating on SP-treated TA15 is slightly oxidation wear.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2020-0283/

Details

Industrial Lubrication and Tribology, vol. 73 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 11 November 2020

Yu Feng, Wei Tao, Yiyang Feng, Xiaoqia Yin, Na Lv and Hui Zhao

Although a laser profile sensor (LPS) can be used to measure dimensions, the “shadow region” generally degrades the accuracy and precision of width measurements. The…

Abstract

Purpose

Although a laser profile sensor (LPS) can be used to measure dimensions, the “shadow region” generally degrades the accuracy and precision of width measurements. The accuracy and precision of such measurements should be improved.

Design/methodology/approach

In this paper, the authors propose herein a technique that combines high dynamic range (HDR) imaging with logistic fitting. First, a HDR image is composed of several images acquired with different exposure times, which augments the grayscale of the object profile and significantly reduces overexposure. Next, the profile is fit to a logistic function, which provides accurate and precise edge coordinates. Finally, given the edge coordinates, the object width is calculated.

Findings

To verify the stability of this logistic algorithm, the authors simulate different noise conditions and different degrees of incomplete edge data. In addition, the progressiveness of the algorithm is demonstrated by comparing the results with those of other algorithms and with the height measurement. Furthermore, the suitability of the system is verified experimentally.

Research limitations/implications

Because of the limitation of the condition of laboratory, in the experimental section, this paper cannot represent perfectly the industrial situation. It makes this section limited in demonstration.

Originality/value

In this paper, the results show that the measurement accuracy and precision of the width is improved and exceeds that of the height measurement. The proposed HDR imaging method with logistic fitting may be applied to LPS width measurements, which should significantly aid the development of LPSs.

Details

Sensor Review, vol. 40 no. 6
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 3 June 2020

Ruipeng Tong, Na Zhang, Xiaolong Wang and Hui Zhao

Safety management system (SMS) has been widely adopted to explore its influence on safety performance (SP). However, most existing researches recognized SMS as a…

Abstract

Purpose

Safety management system (SMS) has been widely adopted to explore its influence on safety performance (SP). However, most existing researches recognized SMS as a one-dimension structure and neglected the influences of its subdimensions. Similarly, the impact of safety responsibility (SR) on SP received little attention. This study aims to explore the relationship between subdimensions of SMS and SP, while incorporating the mediating effect of SR.

Design/methodology/approach

The research data were gathered from safety management evaluation report of a large real estate enterprise in China during 2010–2017. This paper carries out a series of data analyses to explore the impact of SMS and SR on SP. In order to analyze the synergistic impacts of SMS and SR on SP, path analysis, correlation analysis and mediation analysis were conducted using hypotheses concerning with the main subdimensions.

Findings

The results indicated SMS and SR decreased the project risk level and improved SP of real estate projects. Furthermore, the effect of SR partially mediated the relationship between the SMS and SP.

Practical implications

Findings in this research contribute to improve SP in real estate industry as well as other industries by the active assumption of SR and the successful implementation of SMS.

Originality/value

This research shows the relationship between subdimensions of SMS and SP and the mediating role of SR on SMS–SP relationship to improve SP in real estate industry.

Details

Engineering, Construction and Architectural Management, vol. 27 no. 10
Type: Research Article
ISSN: 0969-9988

Keywords

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Article
Publication date: 20 February 2020

Yassine Selami, Na Lv, Wei Tao, Hongwei Yang and Hui Zhao

The purpose of this paper is to propose cuckoo optimization algorithm (COA)-based back propagation neural network (BPNN) to reduce the effect of the nonlinearities…

Abstract

Purpose

The purpose of this paper is to propose cuckoo optimization algorithm (COA)-based back propagation neural network (BPNN) to reduce the effect of the nonlinearities presented in laser triangulation displacement sensors. The 3D positioning and posture sensor allows access to the third dimension through depth measurement; the performance of the sensor varies according to the level of nonlinearities presented in the system, which leads to inaccuracies in measurement.

Design/methodology/approach

While applying optimization approach, the mathematical model and the relationship between the key parameters in the laser triangulation ranging and the indexes of the measuring system were analyzed.

Findings

Based on the performance of the parametric optimization method, the measurement repeatability reached 0.5 µm with an STD value within 0.17 µm, an expanded uncertainty of measurement was within 5 µm, the angle error variation of the object’s rotational plane was within 0.031 degrees and nonlinearity was recorded within 0.006 per cent in a full scale. The proposed approach reduced the effect of the nonlinearity presented in the sensor. Thus, the accuracy and speed of the sensor were greatly increased. The specifications of the optimized sensor meet the requirements for high-accuracy devices and allow wide range of industrial application.

Originality/value

In this paper, COA-based BPNN is proposed for laser triangulation displacement sensor optimization, on the basis of the mathematical model, clarifying the working space and working angle on the measurement system.

Details

Sensor Review, vol. 40 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 1 January 2004

Li‐Wei Mai and Hui Zhao

Retail shopping establishments in the West have evolved through many different stages, in close association with Western lifestyles. The growth of supermarkets has been an…

Abstract

Retail shopping establishments in the West have evolved through many different stages, in close association with Western lifestyles. The growth of supermarkets has been an important part of this trend, and in the 1980s, they were introduced in China. With their distinctive business environment, it is significant to study the success of the distribution technology transfer and how the Chinese consumers have received the Western shopping approach. This study examines supermarket shoppers in Beijing. The results provide an insight into the shopping patterns of Chinese consumers and identify potential problems for international retailers.

Details

International Journal of Retail & Distribution Management, vol. 32 no. 1
Type: Research Article
ISSN: 0959-0552

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Article
Publication date: 21 July 2020

Haiyan Zhang, Muhammad Nadeem, Asim Rauf and Zhao Guo Hui

The purpose of this paper is to suggest the solution of time-fractional Fornberg–Whitham and time-fractional Fokker–Planck equations by using a novel approach.

Abstract

Purpose

The purpose of this paper is to suggest the solution of time-fractional Fornberg–Whitham and time-fractional Fokker–Planck equations by using a novel approach.

Design/methodology/approach

First, some basic properties of fractional derivatives are defined to construct a novel approach. Second, modified Laplace homotopy perturbation method (HPM) is constructed which yields to a direct approach. Third, two numerical examples are presented to show the accuracy of this derived method and graphically results showed that this method is very effective. Finally, convergence of HPM is proved strictly with detail.

Findings

It is not necessary to consider any type of assumptions and hypothesis for the development of this approach. Thus, the suggested method becomes very simple and a better approach for the solution of time-fractional differential equations.

Originality/value

Although many analytical methods for the solution of fractional partial differential equations are presented in the literature. This novel approach demonstrates that the proposed approach can be applied directly without any kind of assumptions.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 31 no. 4
Type: Research Article
ISSN: 0961-5539

Keywords

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