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Open Access
Article
Publication date: 6 September 2021

Yujie Li, Tiantian Chen, Sikai Chen and Samuel Labi

The anticipated benefits of connected and autonomous vehicles (CAVs) include safety and mobility enhancement. Small headways between successive vehicles, on one hand, can cause…

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Abstract

Purpose

The anticipated benefits of connected and autonomous vehicles (CAVs) include safety and mobility enhancement. Small headways between successive vehicles, on one hand, can cause increased capacity and throughput and thereby improve overall mobility. On the other hand, small headways can cause vehicle occupant discomfort and unsafety. Therefore, in a CAV environment, it is important to determine appropriate headways that offer a good balance between mobility and user safety/comfort.

Design/methodology/approach

In addressing this research question, this study carried out a pilot experiment using a driving simulator equipped with a Level-3 automated driving system, to measure the threshold headways. The Method of Constant Stimuli (MCS) procedure was modified to enable the estimation of two comfort thresholds. The participants (drivers) were placed in three categories (“Cautious,” “Neutral” and “Confident”) and 250 driving tests were carried out for each category. Probit analysis was then used to estimate the threshold headways that differentiate drivers' discomfort and their intention to re-engage the driving tasks.

Findings

The results indicate that “Cautious” drivers tend to be more sensitive to the decrease in headways, and therefore exhibit greater propensity to deactivate the automated driving mode under a longer headway relative to other driver groups. Also, there seems to exist no driver discomfort when the CAV maintains headway up to 5%–9% shorter than the headways they typically adopt. Further reduction in headways tends to cause discomfort to drivers and trigger take over control maneuver.

Research limitations/implications

In future studies, the number of observations could be increased further.

Practical implications

The study findings can help guide specification of user-friendly headways specified in the algorithms used for CAV control, by vehicle manufacturers and technology companies. By measuring and learning from a human driver's perception, AV manufacturers can produce personalized AVs to suit the user's preferences regarding headway. Also, the identified headway thresholds could be applied by practitioners and researchers to update highway lane capacities and passenger-car-equivalents in the autonomous mobility era.

Originality/value

The study represents a pioneering effort and preliminary pilot driving simulator experiment to assess the tradeoffs between comfortable headways versus mobility-enhancing headways in an automated driving environment.

Details

Frontiers in Engineering and Built Environment, vol. 1 no. 2
Type: Research Article
ISSN: 2634-2499

Keywords

Article
Publication date: 4 November 2022

Quan Yuan, Ning Li, Yujie Li and Junhua Hao

The purpose of this paper is to study the corrosion behavior of 316L stainless steel under cavitation condition in simulated seawater.

Abstract

Purpose

The purpose of this paper is to study the corrosion behavior of 316L stainless steel under cavitation condition in simulated seawater.

Design/methodology/approach

Electrochemical impedance spectroscopy and electrochemical noise analyses are used to characterize the electrochemical process during the cavitation erosion process.

Findings

Because of good corrosion resistance of this material, mechanical damage is the main cause of cavitation erosion. The alloy surface is in active dissolution state during the cavitation erosion process, and the corrosion rate is accelerated as time prolongs which is verified by electrochemical results.

Originality/value

Electrochemical noise is an effective way to study the corrosion under cavitation erosion process.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 1
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 25 April 2022

Xiang Zhang, Yujie Li, Menghan Li, Guorui Zhang and Xiaori Liu

This paper aims to understand the influence of cylinder liner temperature on friction power loss of piston skirts and the synergistic effect of cylinder liner temperature on…

Abstract

Purpose

This paper aims to understand the influence of cylinder liner temperature on friction power loss of piston skirts and the synergistic effect of cylinder liner temperature on lubrication and heat transfer between piston skirt and cylinder liner.

Design/methodology/approach

A method to calculate the influence of cylinder liner temperature on piston skirt lubrication is proposed. The lubrication is calculated by considering the different temperature distribution of the cylinder liner and corresponding piston temperature calculated by a new multilayer thermal resistance model. This model uses the inner surface temperature of the cylinder liner as the starting point, and the starting temperature corresponding to different positions of the piston is calculated using the time integral average. Besides, the transient heat transfer of mixed lubrication is taken into account. Six temperature distribution schemes of cylinder liner are designed.

Findings

Six temperature distributions of cylinder liner are designed, and the maximum friction loss is reduced by 34.4% compared with the original engine. The increase in temperature in the second part of the cylinder liner will lead to an increase in friction power loss. The increase of temperature in the third part of the cylinder liner will lead to a decrease in friction power loss. The influence of temperature change in the third part of the cylinder liner on friction power loss is greater than that in the second part.

Originality/value

The influence of different temperature distribution of cylinder liner on the lubrication and friction of piston skirt cylinder liner connection was simulated.

Article
Publication date: 28 February 2023

Yesen Zhu, Taoyong Hu, Yujie Li, Junhua Hao, Bin Han and Quan Yuan

The aim of this paper is to construct a device that simulated the seawater splash zone, dynamic waterline zone (splash zone) and full immersion zone. Localized corrosion of 2A12…

Abstract

Purpose

The aim of this paper is to construct a device that simulated the seawater splash zone, dynamic waterline zone (splash zone) and full immersion zone. Localized corrosion of 2A12 aluminum alloy long-scale specimen was studied.

Design/methodology/approach

Corrosion morphologies before and after the corrosion product removal were used to identify corrosion intensity at full seawater immersion zone, dynamic waterline zone (splash zone) and atmospheric zone. The average depth and diameter of corrosion pits in the three zones were evaluated by three-dimensional optical microscopy. The impact of wetting time of the atmospheric zone on the localized corrosion was investigated.

Findings

Corrosion pits were observed on the surface on day 4 for the wetted atmospheric zone (Case 1), and on the surface on day 8 for the alternant wet/dry atmospheric zone (Case 2). The corrosion product layer on the surface for Case 1 was partially broken down while the layer on the surface for Case 2 was intact. Average pitting depth and pitting diameters for Case 1 were more serious than that for Case 2.

Originality/value

The above findings revealed that the humidity of the atmospheric zone had great impact on the localized corrosion of aluminum alloy at the seawater splash zone.

Details

Anti-Corrosion Methods and Materials, vol. 70 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Case study
Publication date: 20 April 2020

Geeta Singh, Rishi Dwesar and Satish Kumar

The purpose of this paper is to explore all the strategies adopted by Uber China to gain more and more market shares of Chinese markets. It included localization of its core…

Abstract

Theoretical basis

The purpose of this paper is to explore all the strategies adopted by Uber China to gain more and more market shares of Chinese markets. It included localization of its core product, adaptation to Chinese demands and tying up with different Chinese companies.

Research methodology

The case study has been prepared after thoroughly studying Uber’s business in China. Secondary data is collected from credible sources such as the Uber website, newspapers, interviews and journal publications. This data helped in arriving at a basic understanding of the company, its objectives, strategies and the business model. The strategies formulated by Uber and the challenges it faced while operating in China are studied and explained based on this secondary data. Various published papers, reports released by reputed organizations and universities, interviews of managers and experts and research papers were also used to develop this case.

Case overview/synopsis

This case is developed considering the bent of today’s consumers toward sharing economy. The scope of businesses based on the concept of sharing economy is very wide and is increasing. China’s sharing economy sector was one of the fastest economies in the world. The case chronicles ride of Uber in China: from its entry in the country, strategies adopted, challenges faced and to the exit from China.

Complexity academic level

International business management at the undergraduate and postgraduate programs in management

Details

The CASE Journal, vol. 16 no. 2
Type: Case Study
ISSN:

Keywords

Article
Publication date: 20 December 2022

Lucas Liang Wang, Qing Dai and Yan Gao

New venture status is the most prominent feature of entrepreneurial startups, but its performance implications have remained under-studied. This study aims to bridge this…

Abstract

Purpose

New venture status is the most prominent feature of entrepreneurial startups, but its performance implications have remained under-studied. This study aims to bridge this knowledge void and offer precise guidelines for startup managers in boosting performance.

Design/methodology/approach

The study develops and tests a multi-perspective model on the linkage between new venture status and firm performance by integrating I/O economics, resource-based view and dynamic capability perspective. The arguments from the first two perspectives point to an adverse effect of new venture status, which is contingent, respectively, on business differentiation and resource endowments. The third perspective grounds a positive relationship between new venture status and performance, which is more pronounced for firms with weaker dynamic capabilities.

Findings

Quantitative evidence from a sample of new and established firms in China shows that the direct effect of new venture status is negative but insignificant. Neither business differentiation nor dynamic capabilities moderate the relationship. Low resource endowments, however, reinforce the negative influence of new venture status. New venture status, thus, shapes firm performance through resource scarcity from resource-based view rather than competitive vulnerability from I/O economics or strategic flexibility from dynamic capability perspective.

Originality/value

Newness and new venture performance have both been extensively examined in literature. But the relationship between them has remained largely omitted. The multi-perspective model and the findings in this study help clarify the confusion as to whether newness is good or bad in the context of an emerging market and reveals the subtle mechanism the effect of newness unfolds.

Details

International Journal of Entrepreneurial Behavior & Research, vol. 29 no. 3
Type: Research Article
ISSN: 1355-2554

Keywords

Article
Publication date: 29 September 2023

Zhen Han, Yuheng Zhao and Mengjie Chen

Coronavirus disease 2019 (COVID-19) has made telecommuting widely valued, but different individuals have different degrees of acceptance of telecommuting. This article aims to…

Abstract

Purpose

Coronavirus disease 2019 (COVID-19) has made telecommuting widely valued, but different individuals have different degrees of acceptance of telecommuting. This article aims to identify suitable individuals for telework and to clarify which types of workers are suitable for what level of telework, set scientific, reasonable hybrid work ratios and processes and measure their suitability.

Design/methodology/approach

First, two working scenarios of different risk levels were established, and the theory of planned behavior (TPB) was used to introduce latent variables, constructing a multi-indicator multi-causal model (MIMIC) to identify suitable individuals, and second, constructing an integrated choice and latent variable (ICLV) model of the working method to determine the suitability of different types of people for telework by calculating their selection probabilities.

Findings

It is possible to clearly distinguish between two types of suitable individuals for telework or traditional work. Their behavior is significantly influenced by the work environment, which is influenced by variables such as age, income, attitude, perceived behavioral control, work–family balance and personnel exposure level. In low-risk scenarios, the influencing factors of the behavioral model for both types of people are relatively consistent, while in high-risk scenarios, significant differences arise. Furthermore, the suitability of telework for the telework-suitable group is less affected by the pandemic, while the suitability for the non-suitable group is greatly affected.

Originality/value

This study contributes to previous literature by: (1) determining the suitability of different population types for telework by calculating the probability of selection, (2) dividing telework and traditional populations into two categories, identifying the differences in factors that affect telework under different epidemic risks and (3) considering the impact of changes in the work scenario on the suitability of telework for employees and classifying the population based on the suitability of telework in order to avoid the potential negative impact of telework.

Details

International Journal of Manpower, vol. 45 no. 4
Type: Research Article
ISSN: 0143-7720

Keywords

Article
Publication date: 5 May 2023

Zhijian Wang, Yin Wang, Lin Liu, Wengsheng Zhu, Jing Li, Yujie Zhao, Haijun Pang and Qilong Wu

The aim of this study is to first investigate the surface integrity of cylindrical rollers under grinding process and then design a reasonable superfinishing process that improve…

Abstract

Purpose

The aim of this study is to first investigate the surface integrity of cylindrical rollers under grinding process and then design a reasonable superfinishing process that improve the anti-fatigue performance of cylindrical rollers by optimization of the surface integrity.

Design/methodology/approach

First, the white and dark layers produced by the grinding process is analyzed by microscope. Then, the influence of oilstone pressure on the stock removal, surface precision and crowned profile are explored. Finally, an optimal superfinishing process and a novel turnaround device are designed to improve surface integrity.

Findings

The experimental results show that as the oilstone pressure increases, the stock removal first increases and then remains stable. This hints that the stock removal of a single-time superfinishing process has an upper limit. In the current conditions, the maximum stock removal is 6 µm. Double-time superfinishing process and the turnover device can effectively eliminate the white and dark layers and improve the symmetric of roller profile. In addition, the surface precision is also improved.

Originality/value

The surface integrity of bearing rollers is very important to the application of industry field. The findings and the methods in the study can be helpful to improve the surface integrity of the bearing rollers.

Details

Industrial Lubrication and Tribology, vol. 75 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 29 October 2020

Jiansheng Qu, Jinyu Han, Lina Liu, Li Xu, Hengji Li and Yujie Fan

The purpose of this paper is to explore the heterogeneity and correlations of agricultural greenhouse gas (GHG) emissions among provinces in China, and then policy implications…

Abstract

Purpose

The purpose of this paper is to explore the heterogeneity and correlations of agricultural greenhouse gas (GHG) emissions among provinces in China, and then policy implications are proposed.

Design/methodology/approach

After agricultural GHG accounting and a pre-analysis of inter-provincial heterogeneity, improved gravity model and the Social Network Analysis (SNA) methods are introduced to construct the network, being carried out from three aspects of the whole network, individual provincial characteristics and cluster analysis.

Findings

(1) There are significant regional variations in agricultural GHG scale among provinces owing to the layout of agricultural production, and the temporal trends show that the direction and speed of agricultural GHG scale change vary among provinces; (2) In terms of inter-provincial correlations, there exists a complex spatial network of agricultural GHG among provinces, which tends to be more complex, intensive and stable, while the status of the provinces in the network also has gradually become more balanced. All provinces played their respective roles in the four clusters of the network with agricultural layout and comparative advantages, and the distribution has continuously optimized.

Practical implications

The inter-provincial network characteristics of agricultural GHG emissions and its evolution have practical implications for differentiated and coordinated agricultural GHG reduction policies at the provincial levels.

Originality/value

This paper innovatively study inter-provincial agricultural GHG correlations in China with the SNA methods used to study economic and social connections in the past. There is some originality in the introduction of network theory and application of the SNA methods, which can provide some reference for researches in similar fields.

Details

China Agricultural Economic Review, vol. 13 no. 1
Type: Research Article
ISSN: 1756-137X

Keywords

Article
Publication date: 4 August 2021

Yujie Tang and Yang Li

This study examines how ethical leadership (EL) influences followers' willingness to conduct unethical pro-organizational behavior (UPB) via reciprocity beliefs at the individual…

Abstract

Purpose

This study examines how ethical leadership (EL) influences followers' willingness to conduct unethical pro-organizational behavior (UPB) via reciprocity beliefs at the individual level and political climate at the group level.

Design/methodology/approach

Two-point survey data were collected from 423 Chinese followers from 81 groups, and multilevel structural equation modeling was conducted to test the hypotheses.

Findings

Individual-level EL unintentionally increases follower UPB willingness by fostering reciprocity beliefs, while group-level EL intentionally reduces follower UPB willingness by controlling the political climate. The political climate plays both a cross-level moderated mediation role and a mediated moderation role between EL and UPB.

Practical implications

When seeking to decrease followers' intention to conduct UPB, managers are advised to use individual-level EL with care when the focus is on reciprocity, and they should consider using group-level EL more when the focus is on controlling political climate.

Originality/value

The study supports two distinct mediating mechanisms by examining individual-level EL (as a moral person) vs group-level EL (as a moral manager) on UPB, thereby revealing the reason for the mixed effects of EL on UPB.

Details

Journal of Managerial Psychology, vol. 37 no. 2
Type: Research Article
ISSN: 0268-3946

Keywords

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