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Article
Publication date: 18 January 2022

Hongwei Li, Xiao Wang, Junmu Lin, Lei Wu and Tong Liu

This study aims to provide a solution of the power flow calculation for the low-voltage ditrect current power grid. The direct current (DC) power grid is becoming a reliable and…

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Abstract

Purpose

This study aims to provide a solution of the power flow calculation for the low-voltage ditrect current power grid. The direct current (DC) power grid is becoming a reliable and economic alternative to millions of residential loads. The power flow (PF) in the DC network has some similarities with the alternative current case, but there are important differences that deserve to be further concerned. Moreover, the dispatchable distributed generators (DGs) in DC network can realize the flexible voltage control based on droop-control or virtual impedance-based methods. Thus, DC PF problems are still required to further study, such as hosting all load types and different DGs.

Design/methodology/approach

The DC power analysis was explored in this paper, and an improved Newton–Raphson based linear PF method has been proposed. Considering that constant impedance (CR), constant current (CI) and constant power (CP) (ZIP) loads can get close to the practical load level, ZIP load has been merged into the linear PF method. Moreover, DGs are much common and can be easily connected to the DC grid, so V nodes and the dispatchable DG units with droop control have been further taken into account in the proposed method.

Findings

The performance and advantages of the proposed method are investigated based on the results of the various test systems. The two existing linear models were used to compare with the proposed linear method. The numerical results demonstrate enough accuracy, strong robustness and high computational efficiency of the proposed linear method even in the heavily-loaded conditions and with 10 times the line resistances.

Originality/value

The conductance corresponding to each constant resistance load and the equivalent conductance for the dispatchable unit can be directly merged into the self-conductance (diagonal component) of the conductance matrix. The constant current loads and the injection powers from dispatchable DG units can be treated as the current sources in the proposed method. All of those make the PF model much clear and simple. It is capable of offering enough accuracy level, and it is suitable for applications in DC networks that require a large number of repeated PF calculations to optimize the energy flows under different scenarios.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 5
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 12 October 2018

Xiaowei Zhu, Yanqiu Chen, Yu Liu, Yongqiang Deng, Changyu Tang, Weilian Gao, Jun Mei, Junhua Zhao, Tong Liu and Jian Yang

The purpose of this paper is to provide additive manufacturing-based solutions for preparation of elastomeric foam with broaden compressive stress plateau.

473

Abstract

Purpose

The purpose of this paper is to provide additive manufacturing-based solutions for preparation of elastomeric foam with broaden compressive stress plateau.

Design/methodology/approach

Mechanic models are developed for obtaining designs of foam cell units with enhanced elastic buckling. An experimental approach is taken to fabricate the foams based on direct ink writing technique. Experimental and simulation data are collected to assist understanding of our proposals and solutions.

Findings

A simple tetragonal structured elastomeric foam is proposed and fabricated by direct ink writing, in which its cell unit is theoretically designed by repeating every four filament layers. The foam exhibits a broader stress plateau, because of the pronounced elastic buckling under compressive loading as predicted by the authors’ mechanic modeling. A two-stage stress plateaus as observed in the foam, being attributed to the dual elastic buckling of the cell units along two lateral directions of the XY plane during compression.

Research limitations/implications

Future work should incorporate more microscopic parameters to tune the elastomeric foam for mechanic performance testing on linear elastic deformation and densification of polymer matrix.

Practical implications

Additive manufacturing offers an alternative to fabricate elastomeric foam with controlled cell unit design and therefore mechanics. Our results comment on its broad space for development such superior cushioning or damping material in the fields of vibration and energy absorption.

Originality/value

This work has contributed to new knowledge on preparation of high performance elastomeric foam by providing a better understanding on its cell structure, being printed using direct ink writing machines.

Details

Rapid Prototyping Journal, vol. 24 no. 9
Type: Research Article
ISSN: 1355-2546

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Article
Publication date: 12 October 2018

Tong Liu, Anuradha Mathrani and Jasper Mbachu

Mobile apps offer construction workers a quick, affordable and user-friendly platform for meeting their information, communication and computing needs, with nearly 13,000…

1056

Abstract

Purpose

Mobile apps offer construction workers a quick, affordable and user-friendly platform for meeting their information, communication and computing needs, with nearly 13,000 construction apps currently available in the market. This study aims to report construction managers’ perspectives on the uptake of mobile apps in the New Zealand construction industry.

Design/methodology/approach

Exploratory research methods were used in two stages. First stage involved interviews with 14 construction managers who were registered with the New Zealand Registered Master Builders Association, followed by an online questionnaire in the second stage. The link of online questionnaire was sent to all members of participating professional organisations by their administrators. In total, 228 responses were received, of which 60 per cent participants completed the entire questionnaire.

Findings

Results show an overall positive attitude towards the use of apps. Perceptions of top management personnel differed slightly from those of middle managers; the former expressed interest in apps usage at strategic level such as improving long-term client relationship management and satisfaction; while the latter were more interested in the apps use at operational and tactical levels such as task- or project-level productivity improvement.

Research limitations/implications

Though bias has been minimised by giving equal opportunity to each member of trade and professional organisations to participate in this survey, of the 228 responses received, only 60 per cent participants completed the entire questionnaire. This is below the minimum requirement for a holistic representation of views. As a result, the findings might not be generalised beyond the study’s scope.

Originality/value

The study provides new insights on the uptake of smartphone apps in New Zealand’s construction sector from the perspective of construction managers who make strategic decisions. The findings have implications for policy formulation and implementation in regards to the use of mobile apps for productivity improvement in the sector. Mobile apps developers could also gain understanding on functional needs and preferences of the construction workforce, which will help in development of more relevant apps.

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Article
Publication date: 21 January 2022

Xuelong Li, Lei Jiang, Xinxin Liu, Ruina Dang, Fusheng Liu, Wang Wei, Tong Zhang and Guoshun Wang

The purpose of this paper is to introduce the modeling and implementation of a novel multimode amphibious robot, which is used for patrol and beach garbage cleaning in the…

390

Abstract

Purpose

The purpose of this paper is to introduce the modeling and implementation of a novel multimode amphibious robot, which is used for patrol and beach garbage cleaning in the land–water transition zone.

Design/methodology/approach

Starting from the design idea of multimode motion, the robot innovatively integrates the guiding fin and wheel together, is driven by the same motor and can achieve multimodal motion such as land, water surface and underwater with only six actuated degrees of freedom. The robot dispenses with the transmission mechanism by directly connecting the servo motor with a reducer to the actuator, so it has the characteristics of simplifying the structure and reducing the quality. And to the best of the authors' knowledge, the design of the robot can be considered the minimal configuration of amphibious robots with the same locomotion capabilities.

Findings

Based on the classical assumptions of underwater dynamics analysis, this paper uses basic airfoil theory to analyze the dynamics of the robot’s horizontal and vertical motions and establishes its simplified dynamics model. Also, the underwater motion of the robot is simulated, and the results are in good agreement with the existing research results. Finally, to verify the feasibility of the robot, a prototype is implemented and fully evaluated by experiments. Experimental results show that the robot can reach the maximum speed of 2.5 m/s and 0.3 m/s on land and underwater, respectively, proving the effectiveness of the robot.

Originality/value

The robot has higher work efficiency with the powerful multimode motion, and its simplified structure makes it more stable while costing less.

Details

Industrial Robot: the international journal of robotics research and application, vol. 49 no. 5
Type: Research Article
ISSN: 0143-991X

Keywords

Available. Open Access. Open Access
Article
Publication date: 20 August 2024

Tong (Tripp) Liu, Caroline Swee Lin Tan and Carolina Quintero Rodriguez

This paper aims to synthesize the existing literature on virtual reality (VR) in the luxury fashion industry, discuss the current practical applications of VR technologies and…

1432

Abstract

Purpose

This paper aims to synthesize the existing literature on virtual reality (VR) in the luxury fashion industry, discuss the current practical applications of VR technologies and review previous research undertaken in the luxury fashion field.

Design/methodology/approach

This paper conducts a systematic review and thematic analysis of existing literature to evaluate current research concerning VR and the luxury fashion industry. This search initially returned a total of 1,131 sources. After establishing and applying criteria of exclusion and inclusion, a total of 46 articles were selected for the thematic analysis.

Findings

Five major themes were identified, including virtual luxury fashion consumption, VR in marketing communication, virtual try-on, VR retail (including virtual fashion retail spaces) and virtual worlds (including customers’ virtual representation as avatars). The importance of these themes for the study of VR in luxury fashion is supported by relevant studies in the literature.

Originality/value

Whilst research into VR use within luxury fashion has increased recently, it remains fragmented. Given the absence of a comprehensive review addressing this topic within the literature, this paper will help scholars and fashion brands better understand the effects of VR on the luxury fashion industry. By integrating current practice and existing research, this paper contributes to a better understanding of how and where VR is used in luxury fashion contexts.

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Article
Publication date: 2 January 2025

Huasong Bai, Jiayi Yang, Ruixue Wang, Tong Liu and Zhanzhong Wang

This study aims to enhance the bioavailability and antioxidant function of vitamin E (VE) by combining it with inositol and choline, exploring their synergistic effects and…

9

Abstract

Purpose

This study aims to enhance the bioavailability and antioxidant function of vitamin E (VE) by combining it with inositol and choline, exploring their synergistic effects and underlying mechanisms.

Design/methodology/approach

An oxidative stress model in mouse hepatocytes was established using hydrogen peroxide to assess the antioxidant effects of combined VE, inositol and choline treatments. Cell viability, the levels of reactive oxygen species (ROS) and malondialdehyde (MDA) and antioxidant enzymes, including superoxide dismutase (SOD) and catalase (CAT), were measured to evaluate protective effects. α-Tocopherol (α-T) and α-tocopherol transfer protein (α-TTP) levels were assessed to determine VE bioavailability. Transcriptome sequencing was conducted to identify gene expression changes and pathways impacted by the treatment.

Findings

An optimal oxidative stress model was established with 641 µM hydrogen peroxide for 6 h. The combination of 20 µM VE, 1.5 mM inositol and 0.3 mM choline significantly improved cell viability, reduced ROS and MDA levels and increased SOD and CAT activities, indicating enhanced antioxidant protection. In addition, α-T and α-TTP levels were higher with this combination, suggesting improved VE bioavailability. Transcriptome analysis revealed that the treatment modulated key pathways linked to inflammation, cancer and lipid metabolism, particularly impacting interleukin-17 and nuclear factor kappa-light-chain-enhancer of activated B cells signaling, cytokine interactions and the alcoholic liver disease pathway.

Originality/value

This study demonstrates a novel approach for improving VE’s bioavailability and effectiveness through its combination with inositol and choline, providing insights that could inform antioxidant therapies and liver health interventions.

Details

Nutrition & Food Science, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0034-6659

Keywords

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Book part
Publication date: 25 January 2021

Man-Yee Kan, Guangye He and Xiaogang Wu

Past studies on housework and marital studies seldom considered the possible endogeneity between these two factors. This chapter analyses data of the Women’s Status Survey 2010 to

Abstract

Past studies on housework and marital studies seldom considered the possible endogeneity between these two factors. This chapter analyses data of the Women’s Status Survey 2010 to investigate the association between satisfaction with family status and housework participation in dual-earner married couples in China. The authors examine the association by ordinary least squares (OLS) regression models and structural equation models (SEM), taking into account of time constraints, economic resources and other demographic characteristics. Results suggest that both men and women are less satisfied with their family status if they share more housework than their partners, after controlling for household income, relative economic contribution, educational qualifications and other factors. Moreover, relative housework contribution is associated more consistently and significantly with satisfaction with family status than absolute housework time. In SEM, the authors include a correlated error term between housework time and satisfaction in the models to take endogeneity between these factors into account. For both urban men and women, relative contribution of housework, but not absolute time of housework, is still negatively associated with family status satisfaction.

Details

Chinese Families: Tradition, Modernisation, and Change
Type: Book
ISBN: 978-1-80071-157-0

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Article
Publication date: 21 June 2022

Dong Guan and Zhengrong Chen

Because of the specific structure and working mechanism, piston speed is only half of its shaft, which causes severally friction between piston and cylinder. Therefore, the main…

84

Abstract

Purpose

Because of the specific structure and working mechanism, piston speed is only half of its shaft, which causes severally friction between piston and cylinder. Therefore, the main purpose of this paper is to investigate the friction and wear characteristics of the incomplete spherical piston in spherical pump comprehensively. Finally, to search the low-friction and wear-resistance structural pattern of the piston, and enhance the durability of spherical pump.

Design/methodology/approach

The non-linear frictional moment model for incomplete spherical piston in spherical pump was derivated quantificationally. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The theoretical wear model of piston–cylinder pair is proposed as well.

Findings

To reduce the frictional moment between incomplete piston and cylinder, the optimised diameter ratio between piston pin and piston should be 0.12 based on the parameter sensitivity analyses. The maximum frictional moment is approximately 2.5 times of the minimum. The total efficiency should be considered synthetically based on the thickness of specific working medium.

Originality/value

The proposed non-linear frictional moment model offers the quantitative estimations. Parameter sensitivity analyses were conducted to find the low-friction structural pattern of the piston. The wear behaviours of the piston and cylinder were analysed to investigate the wear characteristics of the piston.

Details

Industrial Lubrication and Tribology, vol. 74 no. 7
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 11 January 2021

Haijie Wang, Xintian Liu, Que Wu, Xiaolan Wang and Yansong Wang

The purpose of this paper is to obtain a more accurate fatigue life of structures by introducing the surface roughness into fatigue life prediction model.

280

Abstract

Purpose

The purpose of this paper is to obtain a more accurate fatigue life of structures by introducing the surface roughness into fatigue life prediction model.

Design/methodology/approach

Based on the fatigue life prediction model with surface roughness correction, the shock absorber cylinder is taken as an example to verify the feasibility of the improved method. Based on the load of the shock absorber cylinder during driving, fatigue experiments are performed under longitudinal and lateral forces, respectively. Then, the fatigue life predicted by the modified model is compared with that predicted by the traditional model.

Findings

By comparing with the test results, considering the influence of mean stress, the Manson method is more accurate in life prediction. Then, the modified Manson-Coffin and Manson method with surface roughness is more accurate in life prediction under longitudinal force and lateral forces, respectively. This verifies the feasibility of the improved method with the surface roughness.

Originality/value

The research on the influence of surface roughness on fatigue life can lay the technical foundation for the life prediction of products and have great significance to the quality evaluation of products.

Details

Engineering Computations, vol. 38 no. 6
Type: Research Article
ISSN: 0264-4401

Keywords

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Book part
Publication date: 7 December 2023

Berit Sandberg

Pina Bausch is considered one of the most influential choreographers in contemporary dance. She created a new dance language based on a groundbreaking form of joint artistic…

Abstract

Pina Bausch is considered one of the most influential choreographers in contemporary dance. She created a new dance language based on a groundbreaking form of joint artistic inquiry. As a leader, Pina Bausch transformed her company into a chosen family of diverse personalities whom she supported in the development of their individual artistic expressiveness. She encouraged her dancers to contribute to her signature style with inventiveness and authenticity. Her ability to integrate the dancers’ contributions into her pieces and bring them to the fore onstage makes Pina Bausch a prime example of creative leadership. While leveraging her company’s collective genius and international fame through boundless curiosity and artistic integrity, Pina Bausch balanced paradoxes of leading innovation. The essence of her leadership style points to the importance of curiosity, humanity, and embodiment in leader-follower relationships.

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