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Article
Publication date: 7 November 2016

Hongbo Qiu, Wenfei Yu, Bingxia Tang, Weili Li, Cunxiang Yang and Yanfeng Wang

Taking a 2,000 r/min 10 kW permanent magnet motor as an example, the purpose of this paper is to study the influence of driving modes on the performance of permanent magnet motor…

Abstract

Purpose

Taking a 2,000 r/min 10 kW permanent magnet motor as an example, the purpose of this paper is to study the influence of driving modes on the performance of permanent magnet motor at limit conditions, and researched the variation mechanism of motor performance influenced by different driving modes.

Design/methodology/approach

A two-dimensional electromagnetic field model of the permanent magnet motor was established, and a rectangular-wave driving circuit was built. By using the finite element method, the electromagnetic field, current, harmonic content and eddy current loss were calculated when the motor operated at rated load and limit load. On the basis of the motor loss calculation, the temperature field of the motor operating at rated condition and limit condition was researched, and the factors that influence motor limit overload capacity were analyzed. By analyzing the motor loss variation at different load conditions, the change mechanism of the motor temperature field was determined further. Combined with the related experiments, the correctness of the above analysis was verified.

Findings

Permanent magnet synchronous motor (PMSM) driven by sine wave is better compared with brushless direct current motor (BLDCM) driven by rectangular wave in reducing the magnetic field harmonics, motor losses and optimizing the temperature distribution in the motor. The method driven by sine wave could improve the motor output performance including the motor efficiency and the motor overload capacity. The winding temperature is the most important factor that limits the output capability of PMSM operating for a long time. However, because of the large rotor eddy current losses, the permanent magnet temperature is the most important factor that limits the output capability of BLDCM operating for a long time.

Practical implications

The influence of driving modes on the motor magnetic field, losses and temperature distribution, efficiency and overload capacity was determined, and the influence mechanism was also analyzed. Combined with the analysis of the electromagnetic and temperature fields, the advantages of different driving modes were presented. This study could provide an important basis for the design of permanent magnet motors with different driving modes, and it also provides reference for the application of permanent magnet motor.

Originality/value

This paper presents the influence of driving modes on permanent magnet motors. The limit output capacity of the motor with different driving modes was studied, and the key factors limiting the motor output capability were obtained.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 35 no. 6
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 12 February 2018

Abdulmannan Fadel, Andrew Plunkett, Weili Li, Yazan Ranneh, Vivian Elewosi Tessu Gyamfi, Yasser Salmon, Rosemarie Roma Nyaranga and Jason Ashworth

The purpose of this study is to discuss recent research on arabinoxylans from rice bran and wheat byproducts and their immunomodulatory potentials. Also, a potential receptor for…

Abstract

Purpose

The purpose of this study is to discuss recent research on arabinoxylans from rice bran and wheat byproducts and their immunomodulatory potentials. Also, a potential receptor for arabinoxylans is proposed in relation to arabinoxylans structure.

Design/methodology/approach

This review summarises recent publications on arabinoxylans from rice bran and wheat, classification of arabinoxylans, a brief background on their method of extraction and their immunomodulatory potentials as they induce pro-inflammatory response in vitro, in vivo and in humans. The mechanism of action in which arabinoxylans modulate the immune activity is yet to be discovered, However, the authors have proposed a potential receptor for arabinoxylans in relation to arabinoxylans structure and molecular weight.

Findings

The effects of arabinoxylans from rice bran and wheat on the immune response was found to cause a pro-inflammatory response in vitro, in vivo and in humans. Also, the immune response depends on arabinoxylans structure, the degree of branching and origin.

Originality/value

This review paper focuses on the effects of arabinoxylans from rice bran and wheat on immunomodulatory potentials in vitro, in vivo and in humans. A new mechanism of action has been proposed based on the literature and via linking between arabinoxylans and lipopolysaccharide structure, molecular weight and suggested proposed receptor, which might be activated via both of them.

Details

Nutrition & Food Science, vol. 48 no. 1
Type: Research Article
ISSN: 0034-6659

Keywords

Article
Publication date: 15 August 2023

Yongtao Zhao, Weili Li, Xiaoyang Xuan, Jianbang Gao, Jue Wang, Liang Dong, Dawei Zang, Mingjian Wang and Xiankang Zhong

This study aims to evaluate the protection performance of zinc as sacrificial anode for ABS A steel in the presence of H2S under different temperatures, pH and salinities.

Abstract

Purpose

This study aims to evaluate the protection performance of zinc as sacrificial anode for ABS A steel in the presence of H2S under different temperatures, pH and salinities.

Design/methodology/approach

In this paper, weight loss measurements and electrochemical measurements are used to evaluate the corrosion degree of zinc and ABS A steel.

Findings

Under the conditions involved in this work, it is shown that zinc is a nice sacrificial anode with the reason of its stable potential and excellent anode current efficiency according to the relevant standard. And it is also found that the hydrogen evolution does not occur on ABS A steel specimens. The potential difference between cathode and anode is suitable; thus, it can be concluded that each steel is well protected.

Originality/value

To the best of the authors’ knowledge, no other study has analyzed the protection mechanism and effect of zinc as sacrificial anode in H2S-containing environments under high temperature at present.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 6
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 1 March 2021

Wei Li and Liantao Lu

This study aims to investigate the influence of surface roughness and viscosity on micropitting and their influence sequence.

Abstract

Purpose

This study aims to investigate the influence of surface roughness and viscosity on micropitting and their influence sequence.

Design/methodology/approach

Specimens were made of carburized and quenched 18CrNiMo7-6, and different surface roughness was obtained by grinding and shot peening. Tests were carried out on a rolling-sliding tribometer, with different viscosity lubricants and a heavy load under a boundary lubrication condition. The laser confocal microscope was used to measure the aspects, surface roughness, profiles in the contacted region and micropitting damage percentage. A factorial experiment was designed, and the range analysis was applied to find the sequence of influence of surface roughness and viscosity.

Findings

The result shows that surface roughness has a more noticeable influence since the change of viscosity cannot generate sufficient wear loss to suppress micropitting.

Originality/value

The influence sequence of two factors on micropitting was investigated and the reason for the distribution was analyzed.

Details

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

Keywords

Article
Publication date: 11 October 2019

Yuchuan Wu, Shengfeng Qi, Feng Hu, Shuangbao Ma, Wen Mao and Wei Li

In human action recognition based on wearable sensors, most previous studies have focused on a single type of sensor and single classifier. This study aims to use a wearable…

Abstract

Purpose

In human action recognition based on wearable sensors, most previous studies have focused on a single type of sensor and single classifier. This study aims to use a wearable sensor based on flexible sensors and a tri-axial accelerometer to collect action data of elderly people. It uses a statistical modeling approach based on the ensemble algorithm to classify actions and verify its validity.

Design/methodology/approach

Nine types of daily actions were collected by the wearable sensor device from a group of elderly volunteers, and the time-domain features of the action sequences were extracted. The dimensionality of the feature vectors was reduced by linear discriminant analysis. An ensemble learning method based on XGBoost was used to build a model of elderly action recognition. Its performance was compared with the action recognition rate of other algorithms based on the Boosting algorithm, and with the accuracy of single classifier models.

Findings

The effectiveness of the method was validated by three experiments. The results show that XGBoost is able to classify nine daily actions of the elderly and achieve an average recognition rate of 94.8 per cent, which is superior to single classifiers and to other ensemble algorithms.

Practical implications

The research could have important implications for health care, including the treatment and rehabilitation of the elderly, and the prevention of falls.

Originality/value

Instead of using a single type of sensor, this research used a wearable sensor to obtain daily action data of the elderly. The results show that, by using the appropriate method, the device can obtain detailed data of joint action at a low cost. Comparing differences in performance, it was concluded that XGBoost is the most suitable algorithm for building a model of elderly action recognition. This method, together with a wearable sensor, can provide key data and accurate feedback information to monitor the elderly in their rehabilitation activities.

Details

Sensor Review, vol. 39 no. 6
Type: Research Article
ISSN: 0260-2288

Keywords

Article
Publication date: 19 August 2022

Peiqi Ding, Weili Xia, Zhiying Zhao and Xiang Li

Build-operate-transfer (BOT) contracts are widely used in the construction and operation of charging piles for new energy vehicles worldwide and stipulate that governments grant…

Abstract

Purpose

Build-operate-transfer (BOT) contracts are widely used in the construction and operation of charging piles for new energy vehicles worldwide and stipulate that governments grant charging pile operators franchises for a certain period of time to invest in the construction and operation of the charging piles. The charging piles are then transferred to governments when the concession expires. To encourage charging pile operators to build and operate charging piles, governments usually provide two kinds of subsidies, namely construction and operating subsidies.

Design/methodology/approach

The authors establish a typical game model to study the optimal BOT contract between a government and a charging pile operator and their preferences for the two kinds of subsidies.

Findings

First, the authors show that there are substitution and complementarity effects between the concession period and the subsidy level. Second, the operator prefers the construction subsidy (operating subsidy) when the additional operating cost is low (high). The government prefers the operating subsidy (construction subsidy) when consumer sensitivity to the number of charging piles is low (high) and the concession period is short or long (moderate). Finally, the adjusted joint subsidy can not only improve social welfare but also that the charging pile operator can obtain the same profit as under the operating subsidy at a lower subsidy amount.

Originality/value

This work develops the first analytical model to study two subsidies in the construction and operation of charging piles and investigate the optimal BOT contract and subsidy preferences. The insights are compelling not only for the charging pile operator but also for policymakers in practice from a circular economy perspective.

Details

Industrial Management & Data Systems, vol. 123 no. 4
Type: Research Article
ISSN: 0263-5577

Keywords

Article
Publication date: 20 March 2019

Weili Teng, Chenwei Ma, Saeed Pahlevansharif and Jason James Turner

The purpose of this paper is, first, to examine student perspectives of their university experience in terms of the soft employability skills they develop; second, how prepared…

13631

Abstract

Purpose

The purpose of this paper is, first, to examine student perspectives of their university experience in terms of the soft employability skills they develop; second, how prepared those students feel for the future employment market and finally investigate whether there are differences in perceptions between Chinese and Malaysian students given their different educational experience.

Design/methodology/approach

In this study, 361 predominantly Chinese undergraduate students at two universities, one in China and the other in Malaysia completed the 15-item Goldsmiths soft skills inventory using an online survey.

Findings

The results, analysed using factor analysis and confirmatory factor analysis, indicated that the university curriculum develops student soft skills, particularly in the Malaysian university and supports the relationship between soft skill and student preparedness for employment. The results also indicate that compared with the respondents from the Chinese university, the Malaysian university respondents were more likely to be positive to statements concerning their respective university’s ability to develop their soft skills.

Research limitations/implications

Such findings have implications for education providers and business in that it is important for universities to embed soft skills into the curriculum in order to develop graduate work readiness.

Originality/value

What this research contributes is not only consolidation of existing research in the contemporary context of a disruptive jobs market, it takes research forward through analysing student perceptions from two universities, one in Malaysia and the other in China, of the skills they develop at university and the importance of soft skills to them and their perceptions of future employment and employability. Such research will provide insight, in particular, into the role of education providers, the phenomena of underemployment among graduates in China, and be of practical significance to employers and their perception that graduates lack the necessary soft skills for the workplace (Anonymous, 2017a; Stapleton, 2017; British Council, 2015; Chan, 2015).

Details

Education + Training, vol. 61 no. 5
Type: Research Article
ISSN: 0040-0912

Keywords

Article
Publication date: 20 December 2007

Xingdong Shi, Weili Han, Yinsheng Li and Ying Huang

An enterprise application can be quickly built up by service composition. Business process composition is the essence of service composition. To build up such service‐oriented…

Abstract

Purpose

An enterprise application can be quickly built up by service composition. Business process composition is the essence of service composition. To build up such service‐oriented enterprise application, the developer needs an integrated design tool. The purpose of this paper is to present and integrated business‐process driven design for service‐oriented enterprise applications.

Design/methodology/approach

In the approach, there are three phases: business environment modeling, business process modeling, and script compiling. Business environment modeling adopts a new modeling technique which combines both the advantages of use case diagram and sequence diagram in UML. Business process modeling builds a concrete model according to business environment modeling. The mapping algorithms from business environment model to business process model are also given. At script compiling phase, the business process model is compiled into several deployable files. And then the paper presents a demonstration which shows how to apply our approach to developing a supply chain management system for the retail industry.

Findings

The analysis shows that the approach can meet the requirement of service‐composition. The approach can help business expert freely express their business requirement at business environment modeling phase; and help IT expert quickly design service‐oriented enterprise application according to business environment model at business process modeling phase.

Originality/value

This paper proposes a novel integrated approach to model and implement business‐process driven service composition, and presents an integrated tool based Eclipse to implement this approach.

Details

International Journal of Pervasive Computing and Communications, vol. 3 no. 2
Type: Research Article
ISSN: 1742-7371

Keywords

Article
Publication date: 5 March 2024

Cong Zhou, Weili Xia and Taiwen Feng

This study aims to explore how relationship trust and different types of influence strategy (i.e., non-coercive and coercive influence strategy) impact green customer integration…

Abstract

Purpose

This study aims to explore how relationship trust and different types of influence strategy (i.e., non-coercive and coercive influence strategy) impact green customer integration (GCI), while investigating the moderating mechanisms of big data development and social capital.

Design/methodology/approach

Following hierarchical linear regression analysis, the authors examine hypothesized relationships by combining survey data from 206 Chinese manufacturers with secondary data.

Findings

The results show that relationship trust positively affects non-coercive influence strategy, while its impact on coercive influence strategy is insignificant. Non-coercive influence strategy has an inverted U-shaped impact on GCI. Furthermore, big data development flattens the inverted U-shaped relationship between non-coercive influence strategy and GCI. Conversely, social capital steepens the inverted U-shaped relationship between non-coercive influence strategy and GCI.

Practical implications

This study sheds light on managers on how to involve customers in GCI through friendly strategies that favor the involvement of customers and the willingness to develop environmentally friendly initiatives.

Originality/value

Although GCI has received widespread attention, how it can be enhanced remains unclear. These findings provide novel insights into the emerging GCI literature and complement social exchange theory.

Details

Journal of Business & Industrial Marketing, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0885-8624

Keywords

Article
Publication date: 3 July 2017

Hongbo Qiu, Wenfei Yu, Shuai Yuan, Bingxia Tang and Cunxiang Yang

The impact of the loop current (LC) on the motor magnetic field in the analysis of the inter-turn short circuit (ITSC) fault is always ignored. This paper made a comparative study…

Abstract

Purpose

The impact of the loop current (LC) on the motor magnetic field in the analysis of the inter-turn short circuit (ITSC) fault is always ignored. This paper made a comparative study on the electromagnetic field of permanent magnet synchronous motors (PMSM). The purpose of this study is to explore the necessary of the LC existing in the fault analysis and the electromagnetic characteristics of the PMSM with the ITSC fault when taking into account the LC.

Design/methodology/approach

Based on the finite element method (FEM), the fault model was established, and the magnetic density of the fault condition was analyzed. The induced electromotive force (EMF) and the LC of the short circuit ring were studied. The three-phase induced EMF and the unbalance of the three-phase current under the fault condition were studied. Finally, a prototype test platform was built to obtain the data of the fault.

Findings

The influence of the fault on the magnetic density was obtained. The current phase lag when the ITSC fault occurs causes the magnetic enhancement of the armature reaction. The mechanism that LC hinders the flux change was revealed. The influence of the fault on the three-phase-induced EMF symmetry, the three-phase current balance and the loss was obtained.

Originality/value

The value of the LC in the short circuit ring and the influence of it on the motor electromagnetic field were obtained. On the basis of the electromagnetic field calculation model, the sensitivity of the LC to the magnetic density, induced EMF, current and loss were analyzed.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 4
Type: Research Article
ISSN: 0332-1649

Keywords

1 – 10 of 54