Search results

1 – 10 of over 1000
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 13 June 2019

Rui Zhang, Lei Zhao, Dan Xie, Jinlong Song, Wendong Zhang, Lihu Pan and Yanhua Zhang

This study aims to simulate and test the performance of a transmitting and receiving capacitive micro-machined ultrasonic transducer (CMUT). Aimed at detecting demand of the CMUT…

203

Abstract

Purpose

This study aims to simulate and test the performance of a transmitting and receiving capacitive micro-machined ultrasonic transducer (CMUT). Aimed at detecting demand of the CMUT, a matched integrated adjustment circuit was designed through analyzing processing methods of transducer’s weak echo signal.

Design/methodology/approach

Based on the analysis of CMUT array structure and work principle, the CMUT units are designed and the dynamic performance analysis of SIMULINK is given according to the demand of underwater detecting. A transceiver isolation circuit is used to make transmission mode and receiving mode separate. A detection circuit is designed based on the transimpedance amplifier to achieve extraction of high-frequency and weak signal.

Findings

Through experimentation, the effectiveness of the CMUT performance simulation and the transceiver integrated adjustment circuit were verified. In addition, the test showed that CMUT with 400 kHz frequency has wider bandwidth and better dynamic characteristics than other similar transducers.

Originality/value

This paper provides a theoretical basis and design reference for the development and application of CMUT technology.

Access Restricted. View access options
Article
Publication date: 1 September 2021

Yi Zhang Rui Huang

With the booming development of computer, optical and sensing technologies and cybernetics, the technical research in unmanned vehicle has been advanced to a new era. This trend…

258

Abstract

Purpose

With the booming development of computer, optical and sensing technologies and cybernetics, the technical research in unmanned vehicle has been advanced to a new era. This trend arouses great interest in simultaneous localization and mapping (SLAM). Especially, light detection and ranging (Lidar)-based SLAM system has the characteristics of high measuring accuracy and insensitivity to illumination conditions, which has been widely used in industry. However, SLAM has some intractable problems, including degradation under less structured or uncontrived environment. To solve this problem, this paper aims to propose an adaptive scheme with dynamic threshold to mitigate degradation.

Design/methodology/approach

We propose an adaptive strategy with a dynamic module is proposed to overcome degradation of point cloud. Besides, a distortion correction process is presented in the local map to reduce the impact of noise in the iterative optimization process. Our solution ensures adaptability to environmental changes.

Findings

Experimental results on both public data set and field tests demonstrated that the algorithm is robust and self-adaptive, which achieved higher localization accuracy and lower mapping error compared with existing methods.

Originality/value

Unlike other popular algorithms, we do not rely on multi-sensor fusion to improve the localization accuracy. Instead, the pure Lidar-based method with dynamic threshold and distortion correction module indeed improved the accuracy and robustness in localization results.

Details

Sensor Review, vol. 41 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

Access Restricted. View access options
Article
Publication date: 13 January 2025

Rui Zhang, Zehua Dong, Yanjun Zhang, Liuhu Fu and Qiaofeng Bai

This paper aims to propose a new ultrasonic detection method for stainless steel weld defects based on complex synergetic convolutional calculation to solve two problems in the…

9

Abstract

Purpose

This paper aims to propose a new ultrasonic detection method for stainless steel weld defects based on complex synergetic convolutional calculation to solve two problems in the ultrasonic detection of austenitic stainless steel weld defects. These include ignoring the nonlinear information of the imaginary part in the complex domain of the signal and the correlation information between the amplitude of the real part and phase of the imaginary part and subjective dependence of diagnosis model parameters.

Design/methodology/approach

An ultrasonic detection method for weld defects based on complex synergetic convolution calculation is proposed in this paper to address the above issues. By mapping low-density, 1D detection samples to a complex domain space with high representation richness, a multi-scale and multilevel complex synergetic convolution calculation model (CSCC) is designed to match and transform samples to mine amplitude changes, phase shifts, weak phase angle changes and amplitude-phase correlation features deeply from the detection signal. This study proposed an Elite Sine-Cosine Sobol Sampling Dung Beetle Optimization Algorithm, and the detection model CSCC achieves global adaptive matching of key hyperparameters in 19 dimensions. Finally, a regulative complex synergetic convolutional calculation model is constructed to achieve high-performance detection of weld defects.

Findings

Through experiments on a self-developed Taiyuan intelligent detection and information processing weld defect dataset, the results show that the method achieves a detection accuracy of 92% for five types of weld defects: cracks, porosity, slag inclusion and unfused and unwelded components, which represent an average improvement of 11% relative to comparable models. This method is also validated with the PhysioNet electrocardiogram public dataset, which achieves better detection performance relative to the other models.

Originality/value

This method provides a theoretical basis and technical reference for developing and applying intelligent, efficient and accurate ultrasonic defects detection technology.

Details

Sensor Review, vol. 45 no. 2
Type: Research Article
ISSN: 0260-2288

Keywords

Access Restricted. View access options
Article
Publication date: 19 June 2017

Liubov Skavronskaya, Noel Scott, Brent Moyle, Dung Le, Arghavan Hadinejad, Rui Zhang, Sarah Gardiner, Alexandra Coghlan and Aishath Shakeela

This review aims to discuss concepts and theories from cognitive psychology, identifies tourism studies applying them and discusses key areas for future research. The paper aims…

3555

Abstract

Purpose

This review aims to discuss concepts and theories from cognitive psychology, identifies tourism studies applying them and discusses key areas for future research. The paper aims to demonstrate the usefulness of cognitive psychology for understanding why tourists and particularly pleasure travellers demonstrate the behaviour they exhibit.

Design/methodology/approach

The paper reviews 165 papers from the cognitive psychology and literature regarding pleasure travel related to consciousness, mindfulness, flow, retrospection, prospection, attention, schema and memory, feelings and emotions. The papers are chosen to demonstrate the state of the art of the literature and provide guidance on how these concepts are vital for further research.

Findings

The paper demonstrates that research has favoured a behaviourist rather than cognitive approach to the study of hedonic travel. Cognitive psychology can help to understand the mental processes connecting perception of stimuli with behaviour. Numerous examples are provided: top-down and bottom-up attention processes help to understand advertising effectiveness, theories of consciousness and memory processes help to distinguish between lived and recalled experience, cognitive appraisal theory predicts the emotion elicited based on a small number of appraisal dimensions such as surprise and goals, knowledge of the mental organisation of autobiographical memory and schema support understanding of destination image formation and change and the effect of storytelling on decision-making, reconstructive bias in prospection or retrospection about a holiday inform the study of pleasurable experience. These findings indicate need for further cognitive psychology research in tourism generally and studies of holiday travel experiences.

Research limitations/implications

This review is limited to cognitive psychology and excludes psychoanalytic studies.

Practical implications

Cognitive psychology provides insight into key areas of practical importance. In general, the use of a cognitive approach allows further understanding of leisure tourists’ behaviour. The concept of attention is vital to understand destination advertising effectiveness, biases in memory process help to understand visitor satisfaction and experience design and so on. Use of cognitive psychology theory will lead to better practical outcomes for tourists seeking pleasurable experiences and destination managers.

Originality value

This is the first review that examines the application of concepts from cognitive psychology to the study of leisure tourism in particular. The concepts studied are also applicable to study of travellers generally.

Details

Tourism Review, vol. 72 no. 2
Type: Research Article
ISSN: 1660-5373

Keywords

Access Restricted. View access options
Article
Publication date: 24 January 2025

Rui Zhang, Qiang Zhang, Junbo Cheng and Xiaodong Zhou

Achieving accurate trajectory tracking control of robot manipulators is challenging due to dynamic model errors and uncertain payloads. This paper aims to enhance trajectory…

11

Abstract

Purpose

Achieving accurate trajectory tracking control of robot manipulators is challenging due to dynamic model errors and uncertain payloads. This paper aims to enhance trajectory tracking performance for robots with n degrees of freedom (DOF).

Design/methodology/approach

This study proposes a robust motion control framework that combines uncertainty and disturbance estimator with model-based compensation. The proposed framework ensures precise trajectory tracking in robot manipulators. In addition, uncertainties in the high-DOF robot dynamics are estimated through a simple model-based compensation for system error dynamics. The stability of the closed-loop system of the proposed framework is analyzed and proved.

Findings

The results indicate that the proposed framework can significantly reduce tracking errors and increase disturbance resistance. The simulation results of a two-link robotic arm verify the effectiveness of the proposed method. The results of the experiments conducted on a seven-DOF torque-controlled Flexiv4S manipulator demonstrate the superior trajectory tracking performance and robustness of the proposed algorithm.

Originality/value

This study introduces a highly efficient, robust motion control framework for high-DOF robots, which can improve the trajectory tracking performance in the presence of model uncertainties.

Details

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

Keywords

Access Restricted. View access options
Article
Publication date: 3 December 2024

Rui Zhang, Gaoliang Tian, Zichen Tian and Liuchuang Li

This study aims to investigate whether mainland Chinese audit firms’ entry into the H-share market to provide audit services affects their mainland audit pricing.

41

Abstract

Purpose

This study aims to investigate whether mainland Chinese audit firms’ entry into the H-share market to provide audit services affects their mainland audit pricing.

Design/methodology/approach

Using data on A-share listed companies in China from 2008 to 2018, a difference-in-differences model to test the research question is designed. Robustness tests are conducted to rule out alternative explanations and additional tests to shed light on the extent and inner workings of the main effect.

Findings

The entry of mainland audit firms into the H-share audit market leads to a significant decrease in mainland audit pricing. Moreover, this main effect is (i) growing with the importance of H-share audit services to mainland auditors, (ii) stronger for mainland auditors with lower industry specialisation and shorter tenures, (iii) partially mediated by audit efficiency and (iv) greater when mainland clients have higher bargaining power. Furthermore, mainland auditors’ entry into the H-share audit market does not result in significant deterioration in their mainland audit quality, and significantly increases their market share in the mainland audit market.

Originality/value

This study provides new empirical evidence of the relationship between audit firms’ development strategy for internationalisation and audit pricing, extends the literature on auditing issues in emerging markets and should be of potential interest to regulators and investors.

Details

Managerial Auditing Journal, vol. 40 no. 1
Type: Research Article
ISSN: 0268-6902

Keywords

Access Restricted. View access options
Article
Publication date: 14 March 2016

Rui Zhang and Binjie Xin

The purpose of this paper is introducing the image processing technology used for fabric analysis, which has the advantages of objective, digital and quick response.

482

Abstract

Purpose

The purpose of this paper is introducing the image processing technology used for fabric analysis, which has the advantages of objective, digital and quick response.

Design/methodology/approach

This paper briefly describes the key process and module of some typical automatic recognition systems for fabric analysis presented by previous researchers; the related methods and algorithms used for the texture and pattern identification are also introduced.

Findings

Compared with the traditional subjective method, the image processing technology method has been proved to be rapid, accurate and reliable for quality control.

Originality/value

The future trends and limitations in the field of weave pattern recognition for woven fabrics have been summarized at the end of this paper.

Details

Research Journal of Textile and Apparel, vol. 20 no. 1
Type: Research Article
ISSN: 1560-6074

Keywords

Access Restricted. View access options
Article
Publication date: 25 May 2022

Xiongying Niu, Baofang Zhang, Mulele Simasiku and Rui Zhang

This study aims to explore the effect of expatriate supervisors’ managerial coaching behavior on local subordinates’ learning effects through the mediating role of subordinates’…

606

Abstract

Purpose

This study aims to explore the effect of expatriate supervisors’ managerial coaching behavior on local subordinates’ learning effects through the mediating role of subordinates’ thriving at work under the boundary condition of expatriate supervisors’ cultural intelligence.

Design/methodology/approach

This study collected the data form 230 Zambian subordinates and their immediate expatriate supervisors working in the Chinese company in Zambia. Regression analyses and bootstrapping analyses were used to test the authors’ hypothesis.

Findings

The results indicated that expatriate supervisors’ managerial coaching behavior was positively related to local subordinates’ learning effects. In addition, the study also found that local subordinates’ thriving at work mediated the linkage between managerial coaching behavior and learning effects. And expatriate supervisors’ cultural intelligence moderated the indirect relationship between managerial coaching behavior and learning effects via thriving at work, such that the indirect effect was stronger for expatriate supervisors with high rather than low cultural intelligence.

Originality/value

This study contributes to a better understanding of how expatriate supervisors’ managerial coaching behavior influences local subordinates’ learning effects by investigating the mediating effect of thriving at work on the managerial coaching behavior–learning effects link. In addition, the study deepens the understanding of the boundary condition of the associations between managerial coaching behavior and subordinates’ learning effects in a cross-cultural context by investigating the moderating effect of expatriate supervisors’ cultural intelligence.

Details

Chinese Management Studies, vol. 16 no. 4
Type: Research Article
ISSN: 1750-614X

Keywords

Access Restricted. View access options
Article
Publication date: 16 October 2018

Khurram Ashfaq and Zhang Rui

This study aims to revisit the corporate social and environmental disclosure (CSED) practices of Pakistani companies using unique CSED index which measures the CSED through three…

1082

Abstract

Purpose

This study aims to revisit the corporate social and environmental disclosure (CSED) practices of Pakistani companies using unique CSED index which measures the CSED through three dimensions such as theme, news type and nature of information. In addition, the effect of board composition, ownership structure and corporate characteristics on CSED was tested through performing multiple regression analysis.

Design/methodology/approach

For this purpose, data were collected from annual reports of top 120 companies’ selected based on market capitalization for three years period of 2013-2015.

Findings

Based on the descriptive statistics, the results found that overall level of CSED in Pakistan is moderate. However considering CSED using three dimensions, the results demonstrate that highest level of disclosure on the basis of theme is reported in terms of human resource category as compared to other categories where, as in terms of news type and nature of information, analysis shows that companies in Pakistan feel resistant to disclose bad news, monetary and non-monetary aspect of CSED information. Using multiple regression analysis, the results found that all the variables have hypothesized relationship with CSED except government and institutional ownership. The variables such as chairman as non-executive director, board diversity, appointment of independent director as audit committee chairman, CSR committee, industry type and firm size are found to have significant influence on the CSED practices in Pakistan.

Research limitations/implications

These results imply that the CSED phenomenon is still lacking behind. Under individual categories of CSED, descriptive statistics found that environment is still not a matter of concern for companies operating in Pakistan. In addition, the results demonstrate that CSED practices are only performed by very few companies in Pakistan based on standard deviation. In addition, appointment of non-executive and independent director as chairman of board and audit committee and representation of foreigners on the board should be encouraged in order to improve CSED practices in Pakistan.

Originality/value

This study contributes to the existing literature in developing country like Pakistan through using unique CSED index and also making comparison of financial versus non-financial sectors. The author suggests that regulatory authorities in Pakistan must take reasonable steps to make the company’s operations environment-friendly.

Details

Social Responsibility Journal, vol. 15 no. 1
Type: Research Article
ISSN: 1747-1117

Keywords

Access Restricted. View access options
Article
Publication date: 30 November 2023

Dong Chen, Rui Zhang and JiaCheng Jiang

This study aims to investigate the morphology and physicochemical properties of BiOBr/Polyvinylidene fluoride (PVDF) composite membranes and the differences in the properties of…

103

Abstract

Purpose

This study aims to investigate the morphology and physicochemical properties of BiOBr/Polyvinylidene fluoride (PVDF) composite membranes and the differences in the properties of BiOBr/PVDF composite membranes made by adding different precursor ratios during the casting process.

Design/methodology/approach

In this paper, sodium bromide and Bi(NO3)3 were used as precursors for the preparation of BiOBr photocatalysts, and PVDF membranes were modified by using the phase conversion method in conjunction with the in situ deposition method to produce BiOBr/PVDF hydrophilic composite membranes with both membrane separation and photocatalytic capabilities.

Findings

The characterization results confirmed that the composites were successfully and homogeneously co-mingled in the PVDF membranes. The related performance of the composite membrane was tested, and it was found that the composite membrane with the optimal precursor incorporation ratio had good photocatalytic efficiency and antipollution ability; the removal efficiencies of methyl orange, rhodamine B and methylene blue were 80.43%, 85.02% and 86.94%, respectively, in 2.5 h. The photocatalytic efficiency of composite membranes with different precursor ratios increased and then decreased with the increase of the precursor addition ratio.

Originality/value

The composite membrane is prepared by phase conversion method with in situ deposition method, and the BiOBr material has unique advantages for the degradation of organic dyes. The comprehensive experimental data can be known that the composite membrane prepared in this paper has high degradation efficiency and good durability for organic dyes.

Details

Pigment & Resin Technology, vol. 54 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of over 1000
Per page
102050