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Article
Publication date: 28 November 2018

Qigao Fan, Jie Jia, Peng Pan, Hai Zhang and Yan Sun

The purpose of this paper is to relate to the real-time navigation and tracking of pedestrians in a closed environment. To restrain accumulated error of low-cost…

Abstract

Purpose

The purpose of this paper is to relate to the real-time navigation and tracking of pedestrians in a closed environment. To restrain accumulated error of low-cost microelectromechanical system inertial navigation system and adapt to the real-time navigation of pedestrians at different speeds, the authors proposed an improved inertial navigation system (INS)/pedestrian dead reckoning (PDR)/ultra wideband (UWB) integrated positioning method for indoor foot-mounted pedestrians.

Design/methodology/approach

This paper proposes a self-adaptive integrated positioning algorithm that can recognize multi-gait and realize a high accurate pedestrian multi-gait indoor positioning. First, the corresponding gait method is used to detect different gaits of pedestrians at different velocities; second, the INS/PDR/UWB integrated system is used to get the positioning information. Thus, the INS/UWB integrated system is used when the pedestrian moves at normal speed; the PDR/UWB integrated system is used when the pedestrian moves at rapid speed. Finally, the adaptive Kalman filter correction method is adopted to modify system errors and improve the positioning performance of integrated system.

Findings

The algorithm presented in this paper improves performance of indoor pedestrian integrated positioning system from three aspects: in the view of different pedestrian gaits at different speeds, the zero velocity detection and stride frequency detection are adopted on the integrated positioning system. Further, the accuracy of inertial positioning systems can be improved; the attitude fusion filter is used to obtain the optimal quaternion and improve the accuracy of INS positioning system and PDR positioning system; because of the errors of adaptive integrated positioning system, the adaptive filter is proposed to correct errors and improve integrated positioning accuracy and stability. The adaptive filtering algorithm can effectively restrain the divergence problem caused by outliers. Compared to the KF algorithm, AKF algorithm can better improve the fault tolerance and precision of integrated positioning system.

Originality/value

The INS/PDR/UWB integrated system is built to track pedestrian position and attitude. Finally, an adaptive Kalman filter is used to improve the accuracy and stability of integrated positioning system.

Article
Publication date: 14 August 2017

Hai Yan Zhang, Hao Ran Lv, Venkatesh Kodur and Shu Liang Qi

This paper aims to present performance comparison of fiber sheet-strengthened reinforced concrete (RC) beams bonded with geopolymer and epoxy resin under ambient and fire…

Abstract

Purpose

This paper aims to present performance comparison of fiber sheet-strengthened reinforced concrete (RC) beams bonded with geopolymer and epoxy resin under ambient and fire conditions.

Design/methodology/approach

This study presents experimental results of bending tests at ambient temperature and fire resistance tests on two control beams and eight fiber sheet-strengthened RC beams. The test variables include fiber sheet type (carbon fiber [CF] and basalt fiber [BF] sheet), number of layers of fiber sheet (one and two layers) and adhesive agent type (geopolymers and epoxy resin). Data generated from these tests were used to evaluate and compare the strengthening effectiveness of CF-reinforced polymer (CFRP) and CF-reinforced geopolymer (CFRG) at ambient temperature and under fire exposure conditions.

Findings

Test results clearly show that the CFRG system can provide good strengthening effectiveness on RC beams at ambient temperature, as the CFRP system, owing to excellent bond properties of geopolymers. Although geopolymers possess better bonding properties at high temperature than organic matrix, the strengthened beams bonded with geopolymer do not exhibit better fire resistance than that those bonded with epoxy resin, owing to early falling-off of fire insulation. Thus, in CFRG-strengthened beams, relevant measures are to be taken to minimize falling-off of fire insulation to achieve good fire resistance.

Originality/value

The presented results are from unique fire tests and provide valuable insight (and information) on the performance of fiber sheet-strengthened RC beams bonded with geopolymer and epoxy resin under ambient and fire conditions.

Details

Journal of Structural Fire Engineering, vol. 9 no. 3
Type: Research Article
ISSN: 2040-2317

Keywords

Article
Publication date: 17 October 2016

Zhang Hai-ou, Rui Wang, Liye Liang and Wang Gui-lan

The paper aims to introduce the fabrication of a medium steel aircraft part by hybrid deposition and micro-rolling technology (HDMR) and illustrate its advantages, microstructure…

Abstract

Purpose

The paper aims to introduce the fabrication of a medium steel aircraft part by hybrid deposition and micro-rolling technology (HDMR) and illustrate its advantages, microstructure features and mechanical properties of the part.

Design/methodology/approach

The HDMR technology contains two procedures happening almost at the same time: the welding deposition procedure and then the micro-rolling procedure. It takes the gas metal arc welding as the heat source to melt a metal wire and deposit metal in the welding deposition procedure. The metal just deposited is rolled synchronously by a micro roller following the welding torch in micro-rolling procedure almost at the same time layer by layer. The paper presents a contrast of the grain morphology of metal parts produced respectively by HDMR and freedom arc deposition (FAD) and the mechanical properties of metal parts of the same metal from HDMR casting, forging and FAD methods.

Findings

HDMR breaks the dendrite grain of welding beads into the fine crisscross grains. The mechanical properties of metal parts are improved distinctly by the micro-rolling procedure compared to casting, forging and FAD.

Practical implications

In addition, the application of HDMR technology has succeeded in the fabrication of an eligible aircraft metal part, which is quite difficult to achieve using other additive manufacturing (AM) or casting technologies.

Originality/value

HDMR has the advantage of equiponderance manufacturing by micro-rolling compared to other AM technologies. The metal part fabricated by HDMR technology obtains the fine crisscross grains and brings hope for AM metal components with excellent mechanical properties for aircraft applications.

Article
Publication date: 2 May 2019

Yi-Hai Zhang, Hongyu Peng, Hin Wah Chris Cheung, King Man Eric Chong and Chin Fung Philip Chow

The purpose of this paper is to explore the differences between Hong Kong Special Administrative Region (SAR) and Mainland in terms of education and also the influence of it on…

Abstract

Purpose

The purpose of this paper is to explore the differences between Hong Kong Special Administrative Region (SAR) and Mainland in terms of education and also the influence of it on doing comparative educational research. Hong Kong SAR is ruled by the Chinese Government under the framework of “One country, two systems.” It makes Hong Kong SAR different from other Mainland cities based on different aspects including, education. The finding of this paper provides a systematic review about the differences between these two Chinese societies in terms of education and also implication for conducting comparative educational research in these two societies and also generating some implications for cross-national and cross-cultural study in education.

Design/methodology/approach

This paper made references from the framework proposed by Bray and Thomas (1995) in relation to comparative educational research to make comparison between Hong Kong SAR and Mainland China. Multi-level comparison is conducted between two societies in terms of education, especially aspects relating to conducting educational research sat social, school and individual levels.

Findings

This paper identified the influence of “One county, two systems” on education at different levels such as ideology, school management system and use of languages in teaching. Such differences affect the choice of topics, sampling strategy, research design, data analysis and interpretation and also ethical considerations when conducting comparative research between Hong Kong SAR and Mainland China.

Originality/value

This paper is an integrated analysis of conducting educational research in two Chinese societies and provides insights for further discussions and possible research about this topic.

Details

Asian Education and Development Studies, vol. 8 no. 3
Type: Research Article
ISSN: 2046-3162

Keywords

Article
Publication date: 13 November 2017

Jun Zha, Yaolong Chen and Penghai Zhang

The form error of shaft and hole parts is inevitable because of the machining error caused by rotation error of tool axis in machine tools where the elliptical form error is the…

Abstract

Purpose

The form error of shaft and hole parts is inevitable because of the machining error caused by rotation error of tool axis in machine tools where the elliptical form error is the most common in shaft and bearing bush. The purpose of this paper is to present the relationship between the elliptical form error and rotation accuracy for hydrostatic journal bearing in precision spindle and rotation table.

Design/methodology/approach

An error averaging effect model of hydrostatic journal bearing is established by using Reynolds equation, pressure boundary conditions, flux continuity equation of the land and kinetic equation of shaft in hydrostatic journal bearing. The effects of shaft and bearing bush on rotation accuracy were analyzed quantitatively.

Findings

The results reveal that the effect of shaft elliptical form error on rotation accuracy was six times larger than bearing bush. Therefore, to improve the rotation accuracy of hydrostatic journal bearing in spindle or rotation table, the machining error of shaft should be controlled carefully.

Originality/value

An error averaging model is proposed to evaluate the effect of an elliptical form error on rotation accuracy of hydrostatic journal bearings, which solves the Reynolds equation, the flux continuity equation and the kinetic equation. The determination of form error parameters of shaft and bearing bush can be yielded from finding results of this study for precision design of hydrostatic journal bearings.

Details

Industrial Lubrication and Tribology, vol. 69 no. 6
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 4 September 2017

Sanjay Mohan Sharma and Ankush Anand

This paper aims to investigate the effect of CaF2 (calcium fluoride) addition as a solid lubricant on the friction and wear behaviour of sintered Fe-Cu-C materials under different…

Abstract

Purpose

This paper aims to investigate the effect of CaF2 (calcium fluoride) addition as a solid lubricant on the friction and wear behaviour of sintered Fe-Cu-C materials under different loads.

Design/methodology/approach

In this study, the effects of CaF2 added in varying weight percentages on the friction-wear properties of Fe-2Cu-0.8C alloys are investigated. Five Fe-2Cu-0.8C-based compositions comprising CaF2 in 0, 3, 6, 9 and 12 Wt.% were prepared using the single-stage compaction and sintering technique. Friction coefficient, wear loss, hardness and compressive strength of the specimens were measured. The worn-out surfaces were analysed using a scanning electron microscope. Friction and wear tests were carried out on pin-on-disc machine under dry sliding conditions at room temperature.

Findings

The alloy with 3 Wt.% CaF2 was found to be useful in improving wear and friction properties, whereas higher contents of CaF2 resulted in increased wear and friction. Apart from enhanced tribological properties, a slight decrease in the compressive strength was also observed in the 3-Wt.%-CaF2-added sample. Adhesion and abrasion were the prominent wear types observed during this study.

Originality/value

A new self-lubricating composite is developed where CaF2 is used as a solid lubricant in a Fe-Cu-C-based matrix. CaF2, being a high-temperature lubricant, is tried and tested for friction and wear at room temperature, and the results show that the addition of CaF2 in Fe-Cu-C improved its friction and wear properties. Thus, the developed material can be used for antifriction applications.

Details

Industrial Lubrication and Tribology, vol. 69 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 23 August 2013

Hai Guo, Jing Zhao and Jintong Tang

The purpose of this study is to conceptualize the business model from a value network perspective and to investigate how top managers' individual characteristics contribute to…

3110

Abstract

Purpose

The purpose of this study is to conceptualize the business model from a value network perspective and to investigate how top managers' individual characteristics contribute to business model innovation.

Design/methodology/approach

On the basis of upper echelons theory and contingency theory, this study empirically examines the micro‐macro link between top managers' human and social capital and firm business model innovation.

Findings

Using survey data collected from 146 Chinese firms, the findings indicate that both top managers' managerial and entrepreneurial skills and managerial ties significantly lead to business model innovation. Furthermore, the interaction between entrepreneurial skills and managerial ties enhances, yet the interaction between managerial skills and managerial ties inhibits business model innovation.

Originality/value

By proposing a value network‐based definition for the business model, this study provides additional insights into the current debate on the definition and architecture of business model. Further, the current study contributes to an emerging body of business model research by demonstrating, for the first time, that a manager's individual characteristics can both directly and interactively drive business model innovation in the context of emerging economies.

Details

Chinese Management Studies, vol. 7 no. 3
Type: Research Article
ISSN: 1750-614X

Keywords

Article
Publication date: 21 September 2012

Linda C. Isenhour, Diana L. Stone and Donald Lien

The purpose of this paper is to highlight the importance of advancing theory and research in China through identification of unique aspects of Chinese organizational behaviors…

1499

Abstract

Purpose

The purpose of this paper is to highlight the importance of advancing theory and research in China through identification of unique aspects of Chinese organizational behaviors, which can lead to expanded, robust organizational behavior and human resource management models and theories that transcend national boundaries.

Design/methodology/approach

This is a conceptual paper and does not employ research methods.

Findings

The results of studies included in this special issue suggest that researchers can identify elements unique to China in constructs such as psychological capital, work‐to‐family spillover, work‐family conflict, performance appraisal process, and expatriate interactions that further expand theory and research in organizational behavior.

Practical implications

The review of articles in the special issue suggests that managers in organizations in China may want to: develop individuals' psychological capital; train managers on the importance of eliminating abusive behaviors and developing employees' heartiness; adopt family friendly practices; employ performance appraisal process to encourage commitment and organizational citizenship behaviors; and train local country nationals on working with expatriates to enhance organizational effectiveness.

Originality/value

This review provides a unique perspective on employee behavior because it considers such behavior in a Chinese context.

Details

Journal of Managerial Psychology, vol. 27 no. 7
Type: Research Article
ISSN: 0268-3946

Keywords

Article
Publication date: 29 November 2018

Dilek Demirbas, Lauren Wilkinson and David Bennett

The purpose of this paper is to understand the impact of the recent recession on both the automotive manufacturer as well as their suppliers. The research aims to identify if the…

1193

Abstract

Purpose

The purpose of this paper is to understand the impact of the recent recession on both the automotive manufacturer as well as their suppliers. The research aims to identify if the impact has been the same at each of the organizations, or if there has been a difference.

Design/methodology/approach

This paper carries out a case study research, into the need for suppliers to increase their responsiveness following recession and the impact this has had on supplier relations. Face-to-face semi-structured interviews were carried out at the vehicle manufacturer with two members of production control staff from VMUK plus seven production control staff at seven tier 1 suppliers to VMUK.

Findings

Supply chains have been enhanced through an increased level of responsiveness, following the economic downturn and supplier relations have had a positive impact post-recession.

Research limitations/implications

Literature argues that competitive advantage can be achieved through responsiveness, and that responsiveness is critical during a period of volatility and market uncertainty. Furthermore, literature also argues that competitive advantage can be achieved through positive supplier relations. This study investigates both of these arguments.

Originality/value

This study concludes that the positive supplier relations offer a competitive advantage when there is no cost advantage to be found elsewhere. Furthermore, this study concludes that as a direct impact of the recession, supplier relations have improved within the case studies investigated.

Details

Benchmarking: An International Journal, vol. 25 no. 8
Type: Research Article
ISSN: 1463-5771

Keywords

Article
Publication date: 14 September 2022

Jing Zhao, Xin Wang, Biyun Xie and Ziqiang Zhang

This paper aims to present a new kinematics mapping method based on dynamic equivalent points. In teleoperation, this method enables a robotic (follower) arm to mimic human…

Abstract

Purpose

This paper aims to present a new kinematics mapping method based on dynamic equivalent points. In teleoperation, this method enables a robotic (follower) arm to mimic human (leader) arm postures and avoid obstacles in a human-like manner.

Design/methodology/approach

The information of the human arm is extracted based on the characteristics of human arm motion, and the concept of equivalent points is introduced. Then, an equivalent point is determined to transform the robotic arm with a nonhuman-like kinematic structure into an anthropomorphic robotic arm. Based on this equivalent point, a mapping method is developed to ensure that the two arms are similar. Finally, the similarity between the human elbow angle and robot elbow angle is further improved by using this method and an augmented Jacobian matrix with a compensation coefficient.

Findings

Numerical simulations and physical prototype experiments are conducted to verify the effectiveness and feasibility of the proposed method. In environments with obstacles, this method can adjust the position of the equivalent point in real time to avoid obstacles. In environments without obstacles, the similarity between the human elbow angle and robot elbow angle is further improved at the expense of the end-effector accuracy.

Originality/value

This study presents a new kinematics mapping method, which can realize the complete mapping between the human arm and heterogeneous robotic arm in teleoperation. This method is versatile and can be applied to various mechanical arms with different structures.

Details

Industrial Robot: the international journal of robotics research and application, vol. 50 no. 2
Type: Research Article
ISSN: 0143-991X

Keywords

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