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Article
Publication date: 6 November 2017

Youpeng Huangfu, Song Wang, Shuang Wang, Hailin Li, Dongsheng Yuan, Shuhong Wang and Luca Di Rienzo

The purpose of this paper is to implement the macro-modeling and passivity enforcement for the equivalent high frequency circuit model of a single-phase winding for an…

Abstract

Purpose

The purpose of this paper is to implement the macro-modeling and passivity enforcement for the equivalent high frequency circuit model of a single-phase winding for an alternating current (AC) three-phase motor. It provides a stable and strictly passive Foster-type circuit macro-model for the winding. Consequently, a stable circuit network is guaranteed when it is connected with an external passive circuit. The equivalent circuit is validated on a three-phase permanent magnet synchronous motor. Furthermore, the corresponding three-phase windings macro-model could be obtained accordingly.

Design/methodology/approach

The following techniques are used: the least square method, vector fitting method, the fast residue perturbation method, circuit synthesis, sequence quadratic programming method and simulated annealing method.

Findings

This work presents an effective approach to model an equivalent high frequency circuit macro-model for a single-phase winding. Simultaneously, both the characteristics of port passivity and component passivity are guaranteed.

Originality/value

This paper carries out both the port passivity and the component passivity enforcement for a single-phase winding of a motor during the macro-modeling procedure. This equivalent motor winding model can be applied to obtain the conducted electromagnetic interference and the overvoltage performance analysis for an adjustable speed motor drive system.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 36 no. 6
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 16 August 2019

Bi Ying Hu, Yuanhua Li, Chuang Wang, Barry Lee Reynolds and Shuang Wang

The purpose of this paper is to examine the relationship between school climate and teacher stress. Specifically, the authors construct two parsimonious models to test two…

Abstract

Purpose

The purpose of this paper is to examine the relationship between school climate and teacher stress. Specifically, the authors construct two parsimonious models to test two main hypotheses. First, whether preschool collegial leadership predicts teachers’ job stress through the mediating role of teacher self-efficacy; second, whether teacher professionalism influences teachers’ perceptions of occupational stress through the mediating role of teacher self-efficacy.

Design/methodology/approach

The authors conceptualized the mediating role of teacher efficacy as an important mechanism that can help to explain the effect of school climate on teacher stress. School climate consisted of two dimensions: principal collegial leadership and professionalism. Therefore, the authors constructed and examined two mediation models by using Bootstrapping mediation modeling: first, preschool teacher self-efficacy as a mediator between preschool collegial leadership and teacher stress; second, preschool teacher self-efficacy as a mediator between preschool teacher professionalism and teacher stress.

Findings

Results from two mediation analyses showed that principal collegial leadership exerts a significant negative effect on preschool teachers’ stress through the mediating role of teacher self-efficacy. Moreover, professionalism was also a significant predictor of preschool teachers’ stress through the mediating role of teacher self-efficacy.

Research limitations/implications

This study contributes to the literature in terms of understanding the mechanism of how school climate helps to reduce teacher stress. First, the authors found that teachers’ individual well-being can be efficiently enhanced through a more collegial leadership. Second, the preschool leadership teams can create a supportive climate to reduce teachers’ stress by improving teachers’ professionalism.

Originality/value

This study offers a new perspective about understanding the internal and external mechanism of teacher stress. The authors discussed the results in light of the recent push by the Chinese Government to teacher quality improvement in early childhood education. The authors argued for prioritizing support for building a supportive school climate for teachers.

Details

Journal of Educational Administration, vol. 57 no. 6
Type: Research Article
ISSN: 0957-8234

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Article
Publication date: 10 June 2019

Shuang Wang, Gedong Jiang, Xuesong Mei, Chuang Zou, Xian Zhang and Hao Zhang

Because of the compact structure, short flexspline (FS) harmonic drive (HD) is increasingly used. The stress calculation of FS is very important in design and optimization…

Abstract

Purpose

Because of the compact structure, short flexspline (FS) harmonic drive (HD) is increasingly used. The stress calculation of FS is very important in design and optimization of HD system. This paper aims to study the stress calculation methods for short FS, based on mechanics analysis and finite element method (FEM).

Design/methodology/approach

A rapid stress calculation method, based on mechanics analysis, is proposed for the short FS of HD. To verify the stress calculation precision of short FS, a complete finite element model of HD is established. The results of stress and deformation of short FS in different lengths are solved by FEM.

Findings

Through the rapid calculation method, the analytical relationship between circumferential stress and length of cylinder was obtained. And the circumferential stress has proportional relation with the reciprocal of squared length. The FEM results verified that the rapid stress calculation method could obtain accurate results.

Research limitations/implications

The rapid mechanics analysis method is practiced to evaluate the strength of FS at the design stage of HD. And the complete model of HD could contribute to improving the accuracy of FEM results.

Originality/value

The rapid calculation method is developed based on mechanics analysis method of cylinder and equivalent additional bending moment model, through which the analytical relationship between circumferential stress and length of cylinder was obtained. The complete three-dimensional finite element model of HD takes the stiffness of bearing into consideration, which can be used in the numerical simulation in the future work to improve the accuracy.

Details

Engineering Computations, vol. 36 no. 6
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 2 January 2018

Shuang Wang

Hong Kong’s musical scene is rapidly changing along with the evolving media landscape. The purpose of this paper is to examine the new way of Cantopop production and…

Abstract

Purpose

Hong Kong’s musical scene is rapidly changing along with the evolving media landscape. The purpose of this paper is to examine the new way of Cantopop production and dissemination in the new media ecosystem. Furthermore, this study calls for a reconceptualization of the process of Cantopop listening and sharing as a form of public pedagogy within the online public space.

Design/methodology/approach

Based on the investigation into two of the leading local indie bands Kolor and Supper Moment, this study explores the implications that social media and participatory culture have for these indie bands. In this study, the music content and promotion strategy of the two bands, as well as the role of their online audiences are studied.

Findings

Social media leads to more democratic cultural production and distribution. The strong online audience engagement serves as the foundation for the popularity of the two Cantopop indie bands. In their music practice, the lyrics appear to be in alignment with the goals and interests of the listeners, which gives rise to greater participation by its audiences through social media. Under the context of interactive internet culture, listening and sharing Cantopop can be seen as an educational force, thus reinforcing the values and attitudes.

Originality/value

While many important works have examined various aspects of Cantopop, little attention has been paid to the indie bands. This paper attempts to reveal the recent development of local indie bands as a site under the interactive internet culture. It also gives insights to the significant role of Cantopop played in public pedagogy.

Details

Asian Education and Development Studies, vol. 7 no. 1
Type: Research Article
ISSN: 2046-3162

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Article
Publication date: 30 September 2014

Jun Wang, Xiangyu Wang, Wenchi Shou and Bo Xu

The purpose of this research is to investigate a new approach with its supporting building information modelling (BIM) + augmented reality (AR) tool to enhance…

Abstract

Purpose

The purpose of this research is to investigate a new approach with its supporting building information modelling (BIM) + augmented reality (AR) tool to enhance architectural visualisation in building life cycle. Traditional approaches to visualise architectural design concentrate on static pictures or three-dimensional (3D) scale models which cause problems, such as expensive design evolution, lack of stakeholders’ communication and limited reusability. The 3D animated fly-throughs still occur on a computer screen in two-dimensions and seem cold and mechanical, unless done with advanced production software.

Design/methodology/approach

The method of this research included case study and interview. It was, first, stated, from the building process perspective, how the BIM + AR for Architectural Visualisation System (BAAVS) was realised by integrating two types of visualisation techniques: BIM and AR, and four stages of building life cycle. Then the paper demonstrated four case studies to validate the BAAVS. Finally, four interviews were made with each case manager and team members to collect feedback on utilising BAAVS technology. Questions were asked in the areas of benefits, drawbacks and technical limitations with respect to BAAVS.

Findings

Feedback from the stakeholders involved in the four cases indicated that BAAVS was useful and efficient to visualise architectural design and communicate with each other.

Originality/value

This paper demonstrates BAAVS that integrated BIM and AR into architectural visualisation. The system supports an innovative performance that allows: designers to put virtual building scheme in physical environment; owners to gain an immersive and interactive experience; and property sellers to communicate with customers efficiently.

Details

Construction Innovation, vol. 14 no. 4
Type: Research Article
ISSN: 1471-4175

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Book part
Publication date: 23 September 2019

Yi-Ming Wei, Qiao-Mei Liang, Gang Wu and Hua Liao

Abstract

Details

Energy Economics
Type: Book
ISBN: 978-1-83867-294-2

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Article
Publication date: 5 June 2020

Kesheng Lin, Jie Liu, Jia-Min Wu, Yunlong Sun, Feng Li, Yan Zhou and Yusheng Shi

The main cause of aseptic inflammation after an in vivo implantation is that Poly(L-lactide) (PLLA) and Poly(D-lactide) have a slower degradation and absorption rate…

Abstract

Purpose

The main cause of aseptic inflammation after an in vivo implantation is that Poly(L-lactide) (PLLA) and Poly(D-lactide) have a slower degradation and absorption rate, while Poly(D, L-lactide) (PDLLA) has a much faster degradation rate than PLLA because of its amorphous structure. Also, the hydrolyzate of Hydroxyapatite (HA) is alkaline, which can neutralize local tissue peracid caused by hydrolysis of Polylactic acid.

Design/methodology/approach

In this study, the selective laser sintering (SLS) technique was chosen to prepare bone scaffolds using nano-HA/PDLLA composite microspheres, which were prepared by the solid-in-oil-in-water (S/O/W) method. First, the SLS parameters range of bulk was determined by the result of a single-layer experiment and the optimized parameters were then obtained by the orthogonal experiment. The tensile property, hydrophobicity, biocompatibility, biological toxicity and in vitro degradation of the samples with optimized SLS parameters were characterized.

Findings

As a result, the samples showed a lower tensile strength because of the many holes in their interior, which was conducive to better cell adhesion and nutrient transport. In addition, the samples retained their inherent properties after SLS and the hydrophobicity was improved after adding nano-HA because of the OH group. Furthermore, the samples showed good biocompatibility with the large number of cells adhering to the material through pseudopods and there was no significant difference between the pure PDLLA and 10% HA/PDLLA in terms of biological toxicity. Finally, the degradation rate of the composites could be tailored by the amount of nano-HA.

Originality/value

This study combined the S/O/W and SLS technique and provides a theoretical future basis for the preparation of drug-loaded microsphere scaffolds through SLS using HA/PDLLA composites.

Details

Rapid Prototyping Journal, vol. 26 no. 6
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 2 November 2015

Mehran Ashouraie and Nima Jafari Navimipour

Expert Cloud as a new class of Cloud systems provides the knowledge and skills of human resources (HRs) as a service using Cloud concepts. Task scheduling in the Expert…

Abstract

Purpose

Expert Cloud as a new class of Cloud systems provides the knowledge and skills of human resources (HRs) as a service using Cloud concepts. Task scheduling in the Expert Cloud is a vital part that assigns tasks to suitable resources for execution. The purpose of this paper is to propose a method based on genetic algorithm to consider the priority of arriving tasks and the heterogeneity of HRs. Also, to simulate a real world situation, the authors consider the human-based features of resources like trust, reputation and etc.

Design/methodology/approach

As it is NP-Complete to schedule tasks to obtain the minimum makespan and the success of genetic algorithm in optimization and NP-Complete problems, the authors used a genetic algorithm to schedule the tasks on HRs in the Expert Cloud. In this method, chromosome or candidate solutions are represented by a vector; fitness function is calculated based on several factors; one point cross-over and swap mutation are also used.

Findings

The obtained results demonstrated the efficiency of the proposed algorithm in terms of time complexity, task fail rate and HRs utilization.

Originality/value

In this paper the task scheduling issue in the Expert Cloud and improving pervious algorithm are pointed out and the approach to resolve the problem is applied into a practical example.

Details

Kybernetes, vol. 44 no. 10
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 6 November 2017

Songlin Wang, Shuang Feng, Hui Wang, Yu Yao, Jinhua Mao and Xinquan Lai

This paper aims to design a new bandgap reference circuit with complementary metal–oxide–semiconductor (CMOS) technology.

Abstract

Purpose

This paper aims to design a new bandgap reference circuit with complementary metal–oxide–semiconductor (CMOS) technology.

Design/methodology/approach

Different from the conventional bandgap reference circuit with operational amplifiers, this design directly connects the two bases of the transistors with both the ends of the resistor. The transistor acts as an amplifier to amplify the change of voltage, which is convenient for the feedback regulation of low dropout regulator (LDO) regulator circuit, at last to realize the temperature control. In addition, introducing the depletion-type metal–oxide–semiconductor transistor and the transistor operating in the saturation region through the connection of the novel circuit structure makes a further improvement on the performance of the whole circuit.

Findings

This design is base on the 0.18?m process of BCD, and the new bandgap reference circuit is verified. The results show that the circuit design not only is simple and novel but also can effectively improve the performance of the circuit. Bandgap voltage reference is an important module in integrated circuits and electronic systems. To improve the stability and performance of the whole circuit, simple structure of the bandgap reference voltage source is essential for a chip.

Originality/value

This paper adopts a new circuit structure, which directly connects the two base voltages of the transistors with the resistor. And the transistor acts as an amplifier to amplify the change of voltage, which is convenient for the feedback regulation of LDO regulator circuit, at last to realize the temperature control.

Details

Circuit World, vol. 43 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

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Article
Publication date: 1 May 2018

Hao Wang, Yu Wang, Shuang Zhao, Lan-ping Wang and Hui An

The purpose of this paper is to calculate the bank efficiency of removing potential risks that are hidden from the extreme portfolio of bank’s assets and further compare…

Abstract

Purpose

The purpose of this paper is to calculate the bank efficiency of removing potential risks that are hidden from the extreme portfolio of bank’s assets and further compare the differences and causes of bank’s efficiency and potential risk level between China’s representative banks and OECD representative banks in 2011-2015.

Design/methodology/approach

Based on the weight-limited DEA model, this paper calculates the bank’s efficiency and further compares the differences between China’s representative banks and OECD representative banks by using commercial banks’ transnational data.

Findings

By analyzing US representative banks’ data, the authors find that the excessive expansion of the scale of banks’ investment for the non-real economy shrinks after the bubble burst and would not improve the efficiency of banks immediately. The OECD representative banks rather prefer to extreme asset portfolio so that the potential risks gradually increase, while there is a diminishing effect on investments in non-real economies to improve bank efficiency. On the other hand, China’s representative banks have the signs of reducing investment in the real estate market, but the existence of the bubble in the market led to a lagged effect on the impact of adjustment of bank asset portfolio on efficiency.

Research limitations/implications

This paper has practical significance for commercial banks to improve efficiency and reduce credit risks. This is conducive to the implementation of targeted supervision by the banking supervision department.

Practical implications

Based on the lesson that the financial crisis created by the real estate bubble burst in the USA in 2008 and the financial market active guidance of the developed economies, faced with the reality of Chinese real estate market bubble rising and the continuous improvement of Chinese financial market, this paper compares the differences between representative banks in China and OECD, and explores the causes by using the cross-country data of commercial banks.

Originality/value

By adjusting the weight of the input variables in the efficiency measurement, quantifying the risk is often overlooked by the changes in bank efficiency. This potential risk is caused by the bank’s investment preferences in the non-real economy represented by real estate and tradable financial assets.

Details

China Finance Review International, vol. 8 no. 4
Type: Research Article
ISSN: 2044-1398

Keywords

1 – 10 of 113