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Article
Publication date: 4 September 2017

Min Li, Mohammad Hossain Mohammadi, Tanvir Rahman and David Lowther

Manufacturing processes, such as laminations, may introduce uncertainties in the magnetic properties of materials used in electrical machines. This issue, together with…

Abstract

Purpose

Manufacturing processes, such as laminations, may introduce uncertainties in the magnetic properties of materials used in electrical machines. This issue, together with magnetization errors, can cause serious deterioration in the performance of the machines. Hence, stochastic material models are required for the study of the influences of the material uncertainties. The purpose of this paper is to present a methodology to study the impact of magnetization pattern uncertainties in permanent magnet electric machines.

Design/methodology/approach

The impacts of material uncertainties on the performances of an interior permanent magnet (IPM) machine were analyzed using two different robustness metrics (worst-case analysis and statistical study). In addition, two different robust design formulations were applied to robust multi-objective machine design problems.

Findings

The computational analyses show that material uncertainties may result in deviations of the machine performances and cause nominal solutions to become non-robust.

Originality/value

In this paper, the authors present stochastic models for the quantification of uncertainties in both ferromagnetic and permanent magnet materials. A robust multi-objective evolutionary algorithm is demonstrated and successfully applied to the robust design optimization of an IPM machine considering manufacturing errors and operational condition changes.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 5
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 17 October 2019

Yu Yan, Wei Jiang, An Zhang, Qiao Min Li, Hong Jun Li, Wei Chen and YunFei Lei

This study aims to the three major problems of low cleaning efficiency, high labor intensity and difficult to evaluate the cleaning effect for manual insulators cleaning…

Abstract

Purpose

This study aims to the three major problems of low cleaning efficiency, high labor intensity and difficult to evaluate the cleaning effect for manual insulators cleaning in ultra high voltage (UHV) converter station, the purpose of this paper is to propose a basic configuration of UHV vertical insulator cleaning robot with multi-freedom-degree mechanical arm system on mobile airborne platform and its innovation cleaning operation motion planning.

Design/methodology/approach

The main factors affecting the insulators cleaning effect in the operation process have been analyzed. Because of the complex coupling relationship between the influencing factors and the insulators cleaning effect, it is difficult to establish its analytical mathematical model. Combining the non-linear mapping and approximation characteristics of back propagation (BP) neural network, the insulator cleaning effect evaluation can be abstracted as a non-linear approximation process from actual cleaning effect to ideal cleaning effect. An evaluation method of robot insulator cleaning effect based on BP neural network has been proposed.

Findings

Through the BP neural network training, the robot cleaning control parameters can be obtained and used in the robot online operation control, so that the better cleaning effect can be also obtained. Finally, a physical prototype of UHV vertical insulator cleaning robot has been developed, and the effectiveness and engineering practicability of the proposed robot configuration, cleaning effect evaluation method are all verified by simulation experiments and field operation experiments. At the same time, this method has the remarkable characteristics of sound versatility, strong adaptability, easy expansion and popularization.

Originality/value

An UHV vertical insulator cleaning robot operation system platform with multi-arm system on airborne platform has been proposed. Through the coordinated movement of the manipulator each joint, the manipulator can be positioned to the insulator strings, and the insulator can be cleaned by two pairs high-pressure nozzles located at the double manipulator. The influence factors of robot insulator cleaning effect have been analyzed. The BP neural network model of insulator cleaning effect evaluation has been established. The evaluation method of robot insulator cleaning effect based on BP neural network has also been proposed, and the corresponding evaluation result can be obtained through the network training. Through the system integration design, the robot physical prototype has been developed. For the evaluation of other operation effects of power system, the validity and engineering practicability of the robot mechanism, motion planning and the method for evaluating the effect of robot insulator cleaning have been verified by simulation and field operation experiments.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 5 March 2018

Min Li, Arber Caushaj, Rodrigo Silva and David Lowther

This paper aims to presents a novel application of neural network (NN) pattern recognition to ore rock sorting using inductive electromagnetic (EM) sensors.

Abstract

Purpose

This paper aims to presents a novel application of neural network (NN) pattern recognition to ore rock sorting using inductive electromagnetic (EM) sensors.

Design/methodology/approach

The impedance of a metallic rock can be measured with an inductive method based on Faraday’s law and eddy current theory. A virtual rock model is then created for the simulation of the EM measurements. An NN is trained to differentiate between waste and useful ore samples (containing high amount of minerals) based on the EM sensor signals produced by the rocks.

Findings

The NN solution showed high accuracy of rock classification and produced relatively robust results from signals with noise.

Originality/value

A pattern recognition NN was applied to classify low- and high-grade ore samples. It has the potential to determine the approximate amount of conductive materials inside ore rocks through multiple classes. This method can be used to improve the performance of EM-based ore sorting for mineral pre-concentration.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 37 no. 2
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 9 May 2016

Yi-Chun Huang, Min-Li Yang and Ying-Jiuan Wong

This study aims to explore the relationships among institutional pressures, commitment of resources and returns management. Returns management is regarded as a part of…

Abstract

Purpose

This study aims to explore the relationships among institutional pressures, commitment of resources and returns management. Returns management is regarded as a part of supply chain management. However, the research in returns management has received much less attention. To bridge the gap, this study concerns key concepts from two important schools of thought, i.e. institutional theory and the resource-based view, to build up the research model.

Design/methodology/approach

Retailers and maintenance providers in the 3C industry (computers, communication and consumer electronics) in Taiwan were surveyed, and the statistical methods of hierarchical and moderated regression were used to examine the relationships among institutional pressures, commitment of resources and returns management.

Findings

Institutional pressures, comprising non-market and market pressures, affect the implementation of returns management (product return practices and product recovery practices). Commitments of resources positively and significantly moderate the relationship between the pressures imposed by non-market and market actors and product return practices and product recovery practices.

Research limitations/implications

This study investigates only the factors that drive returns management. Future research can examine the relationship between the antecedents and consequences of returns management. Furthermore, returns management may become increasingly critical for firms to develop and perform corporate social responsibility (CSR). Therefore, future research can investigate the relationship between CSR practices and returns management.

Practical implications

This research suggests that managers under institutional pressures should continually pay attention to the effects of external factors on returns management. Additionally, the results reveal that a commitment of resources can reinforce the relationship between the pressures imposed by non-market and market actors and the implementation of returns management. Under significant institutional pressures and resource constraints, managers may increase the effectiveness of returns management while attending to the concerns of non-market and market actors.

Originality/value

This study presents a model that considers three major explicative variables: institutional pressures, resources commitment and returns management. It is the first investigation to integrate three streams of literature on institutional theory, the resource-based view and returns management.

Details

Supply Chain Management: An International Journal, vol. 21 no. 3
Type: Research Article
ISSN: 1359-8546

Keywords

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Article
Publication date: 19 October 2018

Christiana Agbo, Collins Acheampong, Liping Zhang, Min Li and Shai Shao Fu

This study aims to evaluate the use of polyoxyethylene lauryl ether (PLE) as a dispersant in the preparation of novel pigment dispersion with enhanced dispersion ability…

Abstract

Purpose

This study aims to evaluate the use of polyoxyethylene lauryl ether (PLE) as a dispersant in the preparation of novel pigment dispersion with enhanced dispersion ability, which can find application in the printing industry.

Design/methodology/approach

To obtain a good dispersion, PLE was used as a dispersant in pigments dispersion. The colloidal and rheological properties of the PLE-based dispersion, such as particle distribution, zeta potentials and apparent viscosity were evaluated.

Findings

The particle sizes of the pigment dispersions were within the range of 150 to 200 nm. The measurement of zeta potentials varied between −24 to −32 mV, revealing a strong surface charge interaction between pigments and PLE. Subsequently, its stability to high-speed centrifuge and freeze-thaw treatment was carefully investigated. To demonstrate the coverage of pigment particles by PLE, thermogravimetric analysis was carried out. Moreover, X-ray diffraction was used to disclose the combined impacts of PLE and ultrasonic power on the crystal structures of the pigments. Finally, the coloring performance and leveling properties of pigment dispersions on cotton substrates were evaluated by measuring their K/S values (color strength), rub and color fastness properties, which possessed good results.

Research limitations/implications

The dispersant used is incompatible with strong oxidizing agents and strong bases. More so, modification to improve its dispersion properties can be studied.

Practical implications

The use of PLE as a dispersant could be readily used in pigment dispersion processes and other suitable applications. PLE could also be used as a co-surfactant in synergy with other surfactants or dispersants in the dispersion process.

Originality/value

The use of PLE in pigment dispersion as well as investigating its coloring properties on cotton fabric is novel and can find various applications in the dying, printing and coating industry.

Details

Pigment & Resin Technology, vol. 48 no. 1
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 23 July 2018

Min Li, Zhiqiang Wang and Xiande Zhao

The purpose of this paper is to investigate the effects of indigenous technological capability and interpersonal trust on product innovation through supply-chain learning…

Abstract

Purpose

The purpose of this paper is to investigate the effects of indigenous technological capability and interpersonal trust on product innovation through supply-chain learning under a dynamic environment.

Design/methodology/approach

The proposed model is tested with a sample of 300 manufacturers in China.

Findings

The results show that the learning from customers partially mediates the relationship between indigenous technological capability and product innovation, as well as between interpersonal trust with customers and product innovation. In addition, the influence of indigenous technological capability on learning from customers is weakened under a dynamic environment as well as the influence of learning from customers on product innovation.

Originality/value

This study illustrates the comparative roles of indigenous technological capability and interpersonal trust in learning customer knowledge and promoting innovation. It also enriches the innovation research by understanding the learning roles of indigenous technological capability and interpersonal trust under a dynamic environment.

Details

Industrial Management & Data Systems, vol. 118 no. 5
Type: Research Article
ISSN: 0263-5577

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Article
Publication date: 28 April 2020

Wenliang Fan, Wentong Zhang, Min Li, Alfredo H.-S. Ang and Zhengliang Li

Based on univariate dimension-reduction model, this study aims to propose an adaptive anisotropic response surface method (ARSM) and its high-order revision (HARSM) to…

Abstract

Purpose

Based on univariate dimension-reduction model, this study aims to propose an adaptive anisotropic response surface method (ARSM) and its high-order revision (HARSM) to balance the accuracy and efficiency for response surface method (RSM).

Design/methodology/approach

First, judgment criteria for the constitution of a univariate function are derived mathematically, together with the practical implementation. Second, by combining separate polynomial approximation of each component function of univariate dimension-reduction model with its constitution analysis, the anisotropic ARSM is proposed. Third, the high-order revision for component functions is introduced to improve the accuracy of ARSM, namely, HARSM, in which the revision is also anisotropic. Finally, several examples are investigated to verify the accuracy, efficiency and convergence of the proposed methods, and the influence of parameters on the proposed methods is also performed.

Findings

The criteria for constitution analysis are appropriate and practical. Obtaining the undetermined coefficients for every component functions is easier than the existing RSMs. The existence of special component functions is useful to improve the efficiency of the ARSM. HARSM is helpful for improving accuracy significantly and it is more robust than ARSM and the existing quadratic polynomial RSMs and linear RSM. ARSM and HARSM can achieve appropriate balance between precision and efficiency.

Originality/value

The constitution of univariate function can be determined adaptively and the nonlinearity of different variables in the response surface can be treated in an anisotropic way.

Details

Engineering Computations, vol. 37 no. 9
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 15 February 2018

Min Li, Huimin Liu and Jing Zhou

This paper aims to propose a new knowledge creation model called Grey SECI (G-SECI), study the knowledge creation mechanism and the relationship between knowledge creation…

Abstract

Purpose

This paper aims to propose a new knowledge creation model called Grey SECI (G-SECI), study the knowledge creation mechanism and the relationship between knowledge creation models and innovation performance during complex product systems (CoPSs) development. Research and development of CoPSs relies heavily on knowledge creation. However, most scholars have studied CoPS innovation stages from the view of design process of system products, focussing on functional management and project management during the R&D process for CoPS. Attention is lacking with regards to the key and essence of creating a complex technology: the creation of knowledge.

Design/methodology/approach

Modified from the classic SECI model’s spiral process of knowledge creation, a grey-SECI (G-SECI) knowledge creation model is here proposed vis-à-vis three knowledge categories: explicit knowledge, grey knowledge and tacit knowledge. Then, this paper further analyzes the effects of knowledge creation from the perspective of individual and the view of organization. Besides, an empirical study is conducted.

Findings

Statistical analysis indicates that there are three main paths of knowledge creation: individual experience knowledge acquisition, individual communication and reflection and organizational knowledge learning. Results further suggest that knowledge internalization by practice (KIP) is the key mode of knowledge creation, as well as the most important step for high-quality CoPS performance. Moreover, individual innovation performance is influenced by knowledge internalization by reflection and KIP; and organization innovation performance is influenced by knowledge combination and knowledge systematization.

Research limitations/implications

The coverage of geographical distribution is limited. Therefore, there are no data from foreign enterprises. The impact of different geographical cultures on CoPS knowledge creation model could be further investigated; in addition, the statistical analysis results of this study need to be further verified in other industries.

Practical implications

This paper provides a series of insights for CoPS project leaders. The results may also provide practical guidance for the related management personnel in the fields of human resource training, project planning, project quality and technology R&D in CoPS R&D management.

Originality/value

The paper’s main contribution is to modify classic SECI knowledge conversion model by introducing grey knowledge and build a new G-SECI knowledge creation model. Besides, the paper adds empirical evidence on the knowledge creation paths in CoPS and reveals that internalization by practice is the key mode of knowledge creation.

Details

Journal of Knowledge Management, vol. 22 no. 4
Type: Research Article
ISSN: 1367-3270

Keywords

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Article
Publication date: 8 June 2018

Luciana Teixeira Lot, Alice Sarantopoulos, Li Li Min, Simone Reges Perales, Ilka de Fatima Santana Ferreira Boin and Elaine Cristina de Ataide

This paper aims to address problems in patient flow and identify the reasons behind extensive wait time at a public liver transplant outpatient clinic in an education and…

Abstract

Purpose

This paper aims to address problems in patient flow and identify the reasons behind extensive wait time at a public liver transplant outpatient clinic in an education and research hospital through the use of Lean health-care theories.

Design/methodology/approach

This paper opted for the application of Lean thinking and action research strategy. Data were collected through personal observations, interviews with users and team brainstorming. A value stream map was developed, improvement possibilities were identified and non-value-added activities were attempted to be eliminated.

Findings

Significant problems were identified and improvements were implemented and measured. The major remedial measures were: change the scheduling pattern, create a flow chart and a Kanban visual guide for medical students. In addition, an institutional change in the medical appointment scheduling software collaborated in the reduction of time and in the patient’s displacement. The waiting time was reduced by 4.5 h, and the per cent complete and accurate increased by 50 per cent.

Practical implications

The flow was redesigned, and a culture of continuous improvement was introduced. Visiting the place where work was being done, leaders identified and created more value to the process without significant costs. The Gemba Walk was a powerful tool, interacting with people and processes in a Kaizen spirit.

Originality/value

Public health services in developing countries are one of the most deprived social needs of good practice. It will be useful for those who need examples about how to apply Lean tools in health care.

Details

Leadership in Health Services, vol. 31 no. 3
Type: Research Article
ISSN: 1751-1879

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Article
Publication date: 27 August 2019

Wei Jiang, Yu Yan, Qiao Min Li, An Zhang, Hong Jun Li and Daogeng Jiang

The power cable maintenance robot is an important equipment to ensure the reliable operation of high-voltage transmission (HVT) lines and is a useful exploration to…

Abstract

Purpose

The power cable maintenance robot is an important equipment to ensure the reliable operation of high-voltage transmission (HVT) lines and is a useful exploration to achieve high-quality power transmission. In respond to a series of technical problems in the operation process, such as robot shaking, terminal positioning error, camera image blurred and visual servo control difficulty which caused by the influence of high altitude random wind load on the motion control of power maintenance robot. The purpose of this study is to minimizing the impact of wind loads on robot motion control on the high voltage transmission line, so as to obtain the sound motion performance.

Design/methodology/approach

This paper presents a robust stabilization control method for flexible wire power maintenance robot under wind load action, the coupling mathematical model between the flexible wire with the robot has been established, and the robot rolling model under wind load has also been established. According to the tilt sensor, the robot pendulum angle value can be obtained and fitted through sinusoidal function; the robot swing period and frequency under wind load action can be also obtained; the feedforward- and feedback-based robot closed-loop control system is also designed.

Findings

Through the online detection of wind load dection, so as to dynamic control the clamping force of the robot's dual-arm jaws, therefore, the robot robust stabilization control with different grades of wind load can be realized. Finally, the effectiveness and engineering practicability of the proposed algorithm are verified by simulation experiments and field operation experiments. Compared with the conventional proportional integral differential (PID) algorithm, this method can effectively suppress the influence of wind load on the robot robust stabilization motion control, and the robot posture detection operation control has been further optimized.

Originality/value

A robust stabilization control method for power robot under wind load is proposed. The coupling motion model of flexible HVT and robot is established. The mathematical relationship between the robot wind rolling angle and the wind force has been deduced, and the corresponding closed-loop control system with feedforward and feedback has also been designed. Through the design of robust stabilization control algorithm based on mixed sensitivity function, the effectiveness of the mixed sensitivity robust stabilization control algorithm is verified by simulation experiments in MATLAB environment. Compared with the traditional PID algorithm, this method can effectively suppress the influence of large-scale disturbance information represented by wind load on the robot motion control. The engineering practicability of the robot robust stabilization control algorithm is further verified by the robot live damper replacement operation under the field wind load, which further improves the robot operation efficiency and intelligence.

Details

Industrial Robot: the international journal of robotics research and application, vol. 46 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

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