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Article
Publication date: 17 June 2020

Ningning Wu, Hong Guo, Shuai Yang and Shaolin Zhang

This paper aims to study the influence of thermal effect on the performance for a high-speed conical hybrid bearing including stability and minimum oil film thickness.

145

Abstract

Purpose

This paper aims to study the influence of thermal effect on the performance for a high-speed conical hybrid bearing including stability and minimum oil film thickness.

Design/methodology/approach

A thermal hydrodynamic (THD) model and dynamic model of single mass rigid rotor system were established by taking conical hybrid bearing with shallow and deep pockets as the research object, dynamic coefficient and stability parameters of bearing-rotor system were obtained by using finite element method (FEM) and finite difference method (FDM) to solve computational models of Reynolds equation, energy equation and viscosity-temperature equation. Minimum oil film thickness was obtained based on bearing force balance. Dynamic coefficient was compared with previous findings.

Findings

After considering thermal effect, the dimensionless critical mass decreases, a significant decrease in the instability speed, and the stability of the system decreases greatly; the minimum oil film thickness decreases because of thermal effect.

Originality/value

The thermal effect is combined with dynamic characteristics to analyze stability of the rotor system for a conical hybrid bearing. Influence of thermal effect on minimum oil film thickness is studied.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2019-0542/

Details

Industrial Lubrication and Tribology, vol. 72 no. 10
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 3 April 2019

Hong Guo, Shuai Yang, Shaolin Zhang and Zebin Zhang

The purpose of this paper is to study the influence of lubricant temperature-viscosity on the performance for a hydrodynamic journal floating ring bearing (FRB), including…

153

Abstract

Purpose

The purpose of this paper is to study the influence of lubricant temperature-viscosity on the performance for a hydrodynamic journal floating ring bearing (FRB), including ring-journal speed ratio and stability.

Design/methodology/approach

The finite difference method was used to solve computational models of Reynolds equation, energy equation and temperature–viscosity equation. Dynamic coefficients were obtained based on the floating ring balance. The dynamic model of journal and floating ring was established to deduce the stability criterion of single mass symmetrical rigid FRB rotor system by the Routh–Hurwitz method. The outlet temperature and ring-journal speed ratio under different journal speeds were compared to experimental data.

Findings

The temperature–viscosity effect reduces the ring-journal speed ratio and stability of rotor system. According to theoretical and experimental results, the outlet temperature rises and ring-journal ratio drops when the journal speed rises.

Originality/value

The temperature–viscosity effect is combined with dynamic characteristics to analyze the stability of the rotor system and lubrication mechanism for an FRB. Influence of temperature–viscosity on the ring-journal ratio and multi-stable regions of system are studied.

Details

Industrial Lubrication and Tribology, vol. 71 no. 4
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 29 August 2019

Shang Gao, Ying Li and Hong Guo

This study aims to investigate users’ adoption of bike sharing systems in China.

953

Abstract

Purpose

This study aims to investigate users’ adoption of bike sharing systems in China.

Design/methodology/approach

This research combined perceived risk factors with existing technology diffusion theories (e.g. technology acceptance model and unified theory of acceptance and use of technology) to develop a research model to examine users’ adoption of bike sharing systems in China. As a result, a research model with 11 hypotheses was developed. The developed research model was empirically tested using data collected from a survey of 298 users in China. Structural equation modeling was used to analyze the collected data.

Findings

The findings indicated that perceived usefulness, facilitating conditions and perceived risks were important determinants to the adoption of bike sharing systems. However, perceived ease of use and social influence did not have significant positive impacts on users’ behavioral intention to use bike sharing systems.

Practical implications

It is important for service providers to dedicate their time and efforts in maintaining and repairing bikes to ensure that the bikes are in a good condition to be used. System providers need to work on good solutions to better protect users’ personal information and location information.

Originality/value

This study is first of its kinds in investigating the adoption of bike sharing systems by combining technology diffusion theories and perceived risk theory in China.

研究目的

本论文旨在研究用户在中国使用共享单车系统的情况。

研究设计/方法/途径

本论文结合感知风险因素和多个技术扩散理论(比如TAM, UTAUT)来开发一个研究模型, 以研究用户在中国使用共享单车系统的情况。因此, 本论文用十一条假设搭建了一个研究模型。这个研究模型使用问卷采样方式, 收取298份中国用户问卷, 来进行测量。样本通过结构方程模型来进行分析测量。

研究结果

研究结果表明, 感知实用性、辅助条件、感知风险等是重要因素, 决定着共享单车系统的使用。然而, 方便使用和社会影响等因素对用户使用共享单车系统的意向并没有显著积极影响。

论文类型

研究型论文

研究实践意义

服务提供者投入时间和精力来维护维修单车是非常重要的, 这样能保证单车保持在良好的状态以备用户使用。系统供应商需要找到好的解决方式, 来更好地保护个人信息和地点信息。

研究原创性/价值

本论文是首个类似论文, 结合技术扩散理论和感知风险理论, 在中国研究共享单车系统的使用情况。

关键词

UTAUT, TAM, 感知风险, 共享单车系统,使用

Details

Journal of Hospitality and Tourism Technology, vol. 10 no. 3
Type: Research Article
ISSN: 1757-9880

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Article
Publication date: 12 August 2021

Bokolo Anthony Jnr, Sobah Abbas Petersen, Markus Helfert and Hong Guo

Smart city services are supported by information and communication technologies (ICT) referred to as digital technologies which increasingly promise huge opportunities for growth…

1737

Abstract

Purpose

Smart city services are supported by information and communication technologies (ICT) referred to as digital technologies which increasingly promise huge opportunities for growth but are faced with system alignment and data integration issues when providing digital services. Therefore, this study aims to use enterprise architecture (EA) in digital transformation of cities by developing an architecture to address system alignment and data integration in digital transformation of cities.

Design/methodology/approach

Qualitative method is applied to evaluate the presented architecture based on electric-mobility (e-mobility) scenario, and data was collected using case study via interviews from a municipality in Norway to validate the applicability of EA for digital transformation of city services.

Findings

Findings from the interviews were represented in ArchiMate language to model the digital transformation of e-mobility in smart cities. Findings suggest that the architecture serves as a guide to recommend urban administrators of the potential of EA and digital transformation in addressing system alignment and data integration issues in smart cities.

Research limitations/implications

Data used in this study is from a single case, hence there is a need to evaluate the application of EA for digital transformation of city services with data collected from multi-cases.

Practical implications

This study adopts enterprise architecture approach to support city transformation as it has been widely applied by institutions to align business and ICT components.

Social implications

This study provides implication on how municipalities can use EA and digital transformations towards a sustainable smart city.

Originality/value

An architecture is presented that can be used as a guide to help urban developers and designers in deploying sustainable transport policies for smart cities. Additionally, EA is used to foster digitalization towards achieving system alignment and data integration in cities to support urban environment as they digitally transform services provided to citizens.

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Article
Publication date: 20 December 2019

Yanhui Sun, Junkang Guo, Jun Hong and Guanghui Liu

This paper aims to develop a theoretical method to analyze the rotation accuracy of rotating machinery with multi-support structures. The method effectively considers the…

266

Abstract

Purpose

This paper aims to develop a theoretical method to analyze the rotation accuracy of rotating machinery with multi-support structures. The method effectively considers the geometric errors and assembly deformation of parts.

Design/methodology/approach

A method composed of matrix and FEA methods is proposed to do the analysis. The deviation propagation analysis results and external loads are set as boundary conditions of the model which is built with Timoshenko beam elements to calculate the spatial pose of the rotor. The calculation is performed repeatedly as the rotation angle increased to get the rotation trajectories of concerned nodes, and further evaluation is done to get the rotation accuracy. Additionally, to get more reliable results, the bearing motion errors and stiffness are analyzed by a static model considering manufacturing errors of parts.

Findings

The feasibility of the proposed method is verified through a case study of a high-precision spindle. The method reasonably predicts the rotation accuracy of the spindle.

Originality/value

For rotating machinery with multi-support structures, the paper proposes a modeling method to predict the rotation accuracy, simultaneously considering geometric errors and assembly deformation of parts. This would improve the accuracy of tolerance analysis.

Details

Assembly Automation, vol. 40 no. 5
Type: Research Article
ISSN: 0144-5154

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Article
Publication date: 13 August 2024

Hong Guo, Xiaokai Niu and Zhitian Xie

The occurrence of segment cracks caused by load changes in shield tunnels would affect the safety of the tunnel structure. To this end, a three-dimensional fine shield tunnel…

23

Abstract

Purpose

The occurrence of segment cracks caused by load changes in shield tunnels would affect the safety of the tunnel structure. To this end, a three-dimensional fine shield tunnel segment model based on the extended finite element method (XFEM) is established.

Design/methodology/approach

The cracking law of shield segment cracks is studied in two forms: overloading and unloading. The relationship between crack length, width and depth and transverse convergence and deformation is analyzed.

Findings

The results show that the cracks in shield tunnels mainly occur on the outer side of the arch waist and the inner side of the crown and bottom. Under overloading and unloading conditions, the length, width and depth of cracks increase non-linearly as the transverse convergence deformation increases. Under the same convergent deformation, the deeper the buried depth, the smaller the crack length, width and depth. Meanwhile, under overloading conditions, the influence of buried depth on the width and depth of cracks is more significant. In terms of crack width and depth, unloading conditions are more dangerous than overloading conditions.

Originality/value

The findings have a guiding effect for the management of cracks in shield tunnels during operation.

Details

International Journal of Structural Integrity, vol. 15 no. 5
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 22 October 2024

Yingying Chi, Lianghua Chen, Yufei Hu, Yafei Zu, Xue Peng and Jinpei Liu

Green technology, characterized by its environmentally friendly attributes and sustainable practices, has emerged as a crucial tool in harmonizing the economic and ecological…

14

Abstract

Purpose

Green technology, characterized by its environmentally friendly attributes and sustainable practices, has emerged as a crucial tool in harmonizing the economic and ecological benefits. However, the challenge lies in selecting the most effective strategies for acquiring green technology. This paper aims to explore how chemical enterprises choose green technology acquisition strategies across diverse scenarios.

Design/methodology/approach

Considering the influence of competition effects, spillover effects and their interactions on selecting green technology acquisition strategies, this paper develops three decision models (independent R&D, cooperative R&D and technology introduction). Drawing on the duopoly game theory as its theoretical framework, this paper delves into the examination of the economic and environmental benefits within distinct scenarios.

Findings

Cooperative R&D excels in promoting green technology R&D when spillover effects are strong, while independent R&D demonstrates superiority when spillover effects are weak. The threshold for the strength of spillover effects is related to competition effects. Additionally, cooperative R&D typically yields greater financial advantages than independent R&D and technology introduction. Moreover, the economic and environmental benefits may not be optimized simultaneously. Only enterprises that satisfy low competition and spillover effects as well as high competition and spillover effects, can achieve win-win economic and environmental benefits.

Originality/value

Although green technology R&D and introduction are alternative strategies, they have typically been considered separately in prior literature. This study attempts to incorporate green technology R&D and introduction into a strategic system to investigate the selection of green technology acquisition strategies, taking into account competition effects, spillover effects and their interactions.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 8 January 2025

Mingda Ping, Xiangrui Ji, Yan Liu and Weidong Wang

To supply temporary pressure testing devices with favorable performance for emergency environments, this paper aims to present a pressure sensor with a central boss and…

26

Abstract

Purpose

To supply temporary pressure testing devices with favorable performance for emergency environments, this paper aims to present a pressure sensor with a central boss and straight-annular grooves. The structural feature is modeled and optimized by neural network-based method, and the device prototype is fabricated by 3D printing techniques.

Design/methodology/approach

The study initially compares mechanical properties of the proposed structure with two conventional designs using finite element analysis. The impacts from structural dimensions on sensor performance are modeled using a Backpropagation neural network and optimized through genetic algorithms. The sensing diaphragm is fabricated using stereolithography (SLA) 3D printing, while the piezoresistors and necessary interconnects are realized with screen printing techniques.

Findings

The experimental results demonstrate that the fabricated sensor exhibits a sensitivity of 2.8866 mV/kPa and a nonlinearity of 6.81% within the pressure range of 0–100 kPa. This performance is an improvement of 118% in sensitivity and a decrease of 54% in nonlinearity compared to flat diaphragm structure, highlighting the effectiveness of proposed diaphragm configuration.

Originality/value

This research offers a holistic methodology that encompasses the structural design, optimization and fabrication of pressure sensors. The proposed diaphragm and corresponding modelling method can provide a practical approach to enhance the measurement capabilities of pressure sensors. By leveraging SLA printing for diaphragm and screen printing for circuit, the prototype can be produced in a timely manner.

Details

Sensor Review, vol. 45 no. 2
Type: Research Article
ISSN: 0260-2288

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Book part
Publication date: 4 December 2020

Marko Jakšič and Marko Budler

Outsourcing of business-logistics services is a well-established business practice that allows an outsourcer to obtain the services or products from a logistics-service provider…

Abstract

Outsourcing of business-logistics services is a well-established business practice that allows an outsourcer to obtain the services or products from a logistics-service provider (LSP). The outsourcer can order a range of logistics services, including but not limited to warehousing, transportation, and forwarding. The outsourcers had traditionally focused on service-provider selection criteria such as costs, quality, and responsiveness while having devoted considerably less attention to how sustainably the practices are carried out. Past research identified different external and internal motivators that facilitate consideration of sustainability in selection of the service providers, whereas the current study investigates the outsourcers’ perception of importance of environmental sustainability in adoption of green logistics practices and selection of LSPs. We use a vantage point of outsourcers (“buyers”) to conduct the quantitative research based on a survey conducted on large manufacturing companies. The findings reveal a (mis)match between the perception of importance and realized inclusion of environmental-sustainability criteria. Ultimately, this study finds a link between the levels of perception and rate of adoption, and provides recommendations for the future adoption of environmental-sustainability criteria in the selection of the LSPs.

Details

Challenges on the Path Toward Sustainability in Europe
Type: Book
ISBN: 978-1-80043-972-6

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Book part
Publication date: 14 December 2023

Florian Kragulj, Anna Katharina Grill, Raysa Geaquinto Rocha and Arminda do Paço

Sustainable management requires companies to build up new knowledge to acquire the competencies needed for action. This chapter aims to deliver knowledge about sustainability and…

Abstract

Sustainable management requires companies to build up new knowledge to acquire the competencies needed for action. This chapter aims to deliver knowledge about sustainability and knowledge for sustainability. Firstly, we systematically analyse the sustainability literature in the social sciences through a bibliographic analysis and topic modelling using VOSviewer and Mallet software. We outline research directions, themes and critical contributions for each research cluster identified. Additionally, we categorise over 30 definitions of sustainability identified by Meuer, Koelbel, and Hoffmann (2020). Secondly, we enumerate knowledge types needed for effective sustainability transitions of organisations. We trace typologies of sustainable business models and their distinct evaluations of sustainability. In this chapter, we argue that integrating the triad of social, ecological and economic goals is central for sustainability attempts as well as long-term thinking. Therefore, our research offers a comprehensive overview of sustainability in the social sciences supporting researchers and practitioners to navigate this miscellaneous and scattered field. Accordingly, our study is precious to young scholars researching sustainability who want to use the term in an informed and meaningful way.

Details

Innovation, Social Responsibility and Sustainability
Type: Book
ISBN: 978-1-83797-462-7

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