Guoxin Xie, Ziyi Cui, Lina Si and Dan Guo
This paper aims to introduce a series of experimental results which are the extension of our previous novel observations (Xie et al., Soft Matter, 2011), which could be helpful…
Abstract
Purpose
This paper aims to introduce a series of experimental results which are the extension of our previous novel observations (Xie et al., Soft Matter, 2011), which could be helpful for revealing the lubrication failure mechanism in bearings when they are exposed to an electrical environment.
Design/methodology/approach
An experimental apparatus where a ball was in contact with a glass disk coated with a semi-reflective chromium layer. A small volume of oil droplet was put into the microgap of the ball-disk contact. Then, a potential was applied onto the oil micropool formed by the droplet surrounding the contact region.
Findings
It has been found that destabilization of the low-conducting oil micropool around the contact region could be induced after applying a potential. Thin oil films could be drained out of the oil pool and spread on the tribopair surfaces, resulting in the depletion of the oil pool. When the applied potential was increased, the occurrence of spreading would be easier and its development would be more obvious. In contrast, the electrospreading behavior would be suppressed when the oil viscosity, contact load and oil pool size were increased. Thermocapillary force due to thermal effect as a result of the current flow near the oil pool border has been proposed as the main driving force for the spreading behavior. The influences of the operating parameters have been ascribed to the change of the electric current near the oil pool border as well as the corresponding variations in the temperature rise and the surface tension of the oil pool.
Originality/value
This is the first study to directly observe that the lubricant oil micropool around the contact region could deplete after applying a potential, potentially resulting in oil starvation in the contact region.
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Chang Zhang, Jiyin Tian and Dan Guo
Fix-position preloading, centrifugal force and higher temperatures cause the bearing units in angular contact ball bearings to expand, changing the contact load and affecting…
Abstract
Purpose
Fix-position preloading, centrifugal force and higher temperatures cause the bearing units in angular contact ball bearings to expand, changing the contact load and affecting bearing life. This study aims to examine the effect of thermal and centrifugal expansion on the fatigue life of fix-position preloaded angular contact ball bearings in high-speed operating conditions.
Design/methodology/approach
The contact loads on the inner and outer bearing rings were resolved according to the thermal and centrifugal expansion factors in the quasi-static position preloading model. The pressure and frictional stress distribution were used to calculate the subsurface stress in the contact area, while the Zaretsky model was used to determine the relative fatigue life of the inner and outer bearing rings.
Findings
Under fix-position bearing preloading, thermal and centrifugal expansion significantly affected the contact load and relative fatigue life. At the same axial preload, the inner ring contact load was higher than the outer ring contact load, with a maximum difference of 132.3%. The decrease in the inner ring relative life exceeded the outer ring contact load, with a maximum difference of 7.5%, compared to the absence of thermal and centrifugal expansion.
Originality/value
This study revealed the influence of thermal and centrifugal expansion on the fatigue life of angular contact ball bearings in high-speed service conditions.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-03-2023-0065/
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Brenda Nansubuga and Christian Kowalkowski
Subscription offerings are being hailed as the next service growth engine for companies in both business-to-consumer (B2C) and business-to-business (B2B) markets. The study…
Abstract
Purpose
Subscription offerings are being hailed as the next service growth engine for companies in both business-to-consumer (B2C) and business-to-business (B2B) markets. The study analyzes how a manufacturing firm can develop and implement a scalable service-based subscription business model for B2C and B2B customers alongside its existing product-centric model.
Design/methodology/approach
A longitudinal case study is conducted, drawing on 25 in-depth interviews with company executives and dealers in key European markets.
Findings
The study outlines an iterative process model for subscription business model innovation. It reveals key events and decisions taken in developing, implementing, and scaling the new business model and how internal and external tensions involving intermediaries arose and were mitigated during the four stages of the process.
Research limitations/implications
The findings highlight the dynamics of business model innovation processes and underscore the importance of organizational learning, collaborative relationships with channel partners, and strategic talent acquisition during business model innovation.
Practical implications
The findings suggest how product-centric firms can implement new service business models alongside existing product models and what this means for partner and customer journey management.
Originality/value
While servitization research predominantly concerns B2B manufacturers, B2C research focuses on digital subscription contexts. The study bridges this divide by investigating the move to subscriptions in both markets.
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Min Tao, Hongwei Li and Huanjun Xu
The purpose of this paper is to get hold of the main influence factors of the investment efficiency of environmental governance and control them to improve its efficiency…
Abstract
Purpose
The purpose of this paper is to get hold of the main influence factors of the investment efficiency of environmental governance and control them to improve its efficiency sensitively and employ full use of the investment of environmental governance.
Design/methodology/approach
The assessment index system of the investment efficiency of environmental governance is built. Its investment efficiency is assessed based on data envelopment analysis (DEA). The influence degree on the efficiency between each assessment index is calculated by the grey incidence degree analysis method to find the key influence factors. The efficiency of the investment in the environmental governance can be improved by managing and controlling the key factors.
Findings
The results prove that it is available by the data of 14 cities in Shandong Province in 2008. The key influence factors of the investment efficiency of the environmental governance are: total investment in the treatment of environmental pollution (F1); industrial soot removal (F3); industrial wastewater meeting discharge standards (F2); and the volume of garbage disposal (F9).
Practical implications
The method exposed in the paper can be used to solve investment efficiency problem of the environmental governance of the other provinces, or other years and even other countries.
Originality/value
The paper succeeds in solving investment efficiency problem of the environmental governance by DEA and grey incidence degree analysis method.
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Qiang Guo, Dan Zhu, Mao-Tang (Brian) Lin, Fangxuan (Sam) Li, Peter B. Kim, De Du and Yan Shu
This research aims to use meta-analytical structural equation modeling to look into how hospitality employees use technology at work. It further investigates if the relationship…
Abstract
Purpose
This research aims to use meta-analytical structural equation modeling to look into how hospitality employees use technology at work. It further investigates if the relationship between the constructs of the technology acceptance model (TAM) is moderated by job level (supervisory versus non-supervisory) and different cultures (eastern versus western).
Design/methodology/approach
In total, 140 relationships from 30 empirical studies (N = 6,728) were used in this study’s data analysis in accordance with the preferred reporting items for systematic reviews and meta-analysis.
Findings
The findings demonstrated that perceived usefulness had a greater influence on “user attitudes” and “acceptance intention” than perceived ease of use. This study also identified that the effect sizes of relationships among TAM constructs appeared to be greater for supervisory employees or in eastern cultures than for those in non-supervisory roles or western cultures.
Practical implications
The findings provide valuable information for practitioners to increase the adoption of employee technology. Practitioners need to focus on the identification of hospitality employee attitudes, social norms and perceived ease of use. Moreover, hospitality practitioners should be cautious when promoting the adoption of new technologies to employees, as those at different levels may respond differently.
Originality/value
This is the very first empirical investigation to meta-analyze the predictive power of the TAM in the context of hospitality staff technology adoption at the workplace. The findings also demonstrated differences in the predictive power of TAM constructs according to job level and cultural differences.
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Xiaoyong Wei, Feng Ju, Bai Chen, Hao Guo, Dan Wang, Yaoyao Wang and Hongtao Wu
There is an increasing popularity for the continuum robot in minimally invasive surgery owing to its compliance and dexterity. However, the dexterity takes the challenges in…
Abstract
Purpose
There is an increasing popularity for the continuum robot in minimally invasive surgery owing to its compliance and dexterity. However, the dexterity takes the challenges in loading and precise control because of the absence of the shape tracking for the continuum robot. The purpose of this paper is to propose a new type of continuum manipulator with variable stiffness that can track the bending shape timely.
Design/methodology/approach
The low-melting-point alloy (LMPA) is used to implement the stiffness variation and shape detection for the continuum manipulator. A conceptual design for a single module is presented, and the principle of stiffness control based on the established static model is formulated. Afterward, a shape detection method is introduced in which the shape of the continuum manipulator can be detected by measuring the resistance of every LMPA. Finally, the effect of the proposed variable stiffness method is verified by simulation; the variable stiffness and shape detection methods are evaluated by experiments.
Findings
The results from the simulations and experiments indicate that the designed continuum manipulator has the ability of stiffness variation over 42.3% and the shape detection method has high precision.
Originality/value
Compared with conventional structures, the novel manipulator has a simpler structure and integrates the stiffness variation and shape detection capabilities with the LMPA. The proposed method is promising, and it can be conveniently extended to other continuum manipulators.
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Shreya Pal, Mantu Kumar Mahalik and Hrushikesh Mallick
This study examines the role of monetary and fiscal policies in shaping innovation for a balanced panel sample of seven emerging and five advanced Asian economies.
Abstract
Purpose
This study examines the role of monetary and fiscal policies in shaping innovation for a balanced panel sample of seven emerging and five advanced Asian economies.
Design/methodology/approach
Using the Driscoll–Kraay estimator as a baseline technique and panel-corrected standard errors and kernel-based regularised least squares as robust methods, this study explores the factors that influence innovation in both emerging and advanced Asian economies from 1990 to 2021. Based on the Morgan Stanley Capital International categorisation, this study has used a sample of seven emerging and five advanced Asian nations to empirically understand the factors shaping innovation.
Findings
The findings indicate that broad money and economic growth have positive effects on innovation, whereas tax revenue, governance quality and economic globalisation indicate negative effects in emerging Asia. The findings further indicate that tax revenue, economic growth, governance quality and economic globalisation favour innovation in advanced Asia. The authors also find an adverse impact of broad money on total innovation in advanced Asia.
Originality/value
These findings are quite helpful for the stakeholders and policymakers looking for efficient and long-lasting innovation initiatives.
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Hao Guo, Feng Ju, Ning Wang, Bai Chen, Xiaoyong Wei, Yaoyao Wang and Dan Wang
Continuum manipulators are often used in complex and narrow space in recent years because of their flexibility and safety. Vision is considered to be one of the most direct…
Abstract
Purpose
Continuum manipulators are often used in complex and narrow space in recent years because of their flexibility and safety. Vision is considered to be one of the most direct methods to obtain its spatial shape. However, with the improvement of the cooperation requirements of multiple continuum manipulators and the increase of space limitation, it is impossible to obtain the complete spatial shape information of multiple continuum manipulators only by several cameras.
Design/methodology/approach
This paper proposes a fusion method using inertial navigation sensors and cameras to reconstruct the shape of continuum manipulators in the whole workspace. The camera is used to obtain the position information, and the inertial navigation sensor is used to obtain the attitude information. Based on the above two information, the shape of the continuum manipulator is reconstructed by fitting Bézier curve.
Findings
The experiment result of single continuum manipulator shows that the cubic Bézier curves is applicable to curve fitting of variable curvature, the maximum fitting error is about 2 mm. Meanwhile, the experiment result shows that this method is not affected by obstacles and can still reconstruct the shape of the continuum manipulators in 3-D space by detecting the position and attitude information of the end.
Originality/value
According to the authors’ knowledge, this is the first study on spatial shape reconstruction of multiple continuum manipulators and the first study to introduce inertial navigation sensors and cameras into the field of shape reconstruction of multiple continuum manipulators in narrow space. This method is suitable for shape reconstruction of manipulator with variable curvature continuum manipulator. When the vision of multiple continuum manipulators is blocked by obstacles, the spatial shape can still be reconstructed only by exposing the end point. The structure is simple, but it has certain accuracy within a certain range.
Details
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Xin Guo, Jiesong Tu, Zhibin Fan, Baoshuai Du, Hongfei Shang, Jiangfeng An and Dan Jia
Corrosion thinning reduces the effective cross-sectional areas of steel structures and degrades their mechanical properties. This study aims to investigate the relationship…
Abstract
Purpose
Corrosion thinning reduces the effective cross-sectional areas of steel structures and degrades their mechanical properties. This study aims to investigate the relationship between the corrosion thinning of carbon steel for transmission towers and the degradation of its mechanical properties.
Design/methodology/approach
A macroscopic finite element model of a transmission tower was established and then combined with the corrosion thinning and mechanical properties of Q355 steel in different test periods measured in neutral salt spray, SO2 atmosphere and wet heat environments to conduct a finite element simulation of a transmission tower with different corrosion thinning of Q355 steel.
Findings
When the residual thickness of the tower leg angle was reduced to 4.03 mm, the maximum stress solved in the simulation exceeded the yield strength, with the tower already at risk of collapse owing to corrosion failure under extreme conditions of basic wind speed.
Originality/value
This study innovatively utilises transmission tower finite element models and experimental data from mechanical degradation experiments to quantify the relationship between corrosion thinning and the mechanical properties of Q355 steel, ensuring the effective assessment of the mechanical properties of corroded transmission towers.
Details
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Wenchao Ma, Lina He, Zeng Dan, Guanyi Chen and Xuebin Lu
With the rapid development of China’s urbanisation and market economy, municipal solid waste (MSW) generation is increasing dramatically. In response to the threat of…
Abstract
With the rapid development of China’s urbanisation and market economy, municipal solid waste (MSW) generation is increasing dramatically. In response to the threat of environmental pollution and the potential value of converting waste into energy, both the government and the public are now paying more attention to MSW treatment and disposal methods. In 2014, 178.6 million tonnes of MSW was collected at a safe treatment rate of 84.8%. However, the treatment methods and the composition of MSW are influenced by the collection area, its gross domestic product, population, rainfall and living conditions. This chapter analysed the MSW composition properties of Lhasa, Tibet, compared with other cities, such as Beijing, Guangzhou and so forth. The research showed that the moisture content of MSW in Lhasa approaches 31%, which is much lower than the other cities mentioned previously. The proportion of paper and plastics (rubbers) collected was 25.67% and 19.1%, respectively. This was 1.00–3.17 times and 0.75–2.44 times more than those found in Beijing and Guangzhou, respectively. Non-combustibles can reach up to 22.5%, which was 4.03–9.11 times that of Beijing and Guangzhou, respectively. The net heating values could reach up to 6,616 kilojoule/kilogram. The food residue was only half the proportion found in other cities. Moreover, the disposal method applied in each city has also been studied and compared.