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Article
Publication date: 22 July 2019

Haichen Zhou, Dejun Zheng, Yongming Li and Junwei Shen

To further provide some insight into mobile library (m-library) applications (apps) user needs and help libraries or app providers improve the service quality, the purpose of this…

746

Abstract

Purpose

To further provide some insight into mobile library (m-library) applications (apps) user needs and help libraries or app providers improve the service quality, the purpose of this paper is to explore all the types of user improvement needs and to discover which need is the most important based on user results.

Design/methodology/approach

Data were collected from more than 27,000 m-library app users from 16 provinces and autonomous regions in China. Text analysis using latent Dirichlet allocation and Word2Vec was carried out by text preprocessing. Furthermore, a visual presentation was conducted through pyLDAvis and word cloud. Finally, combined with expert opinions, the results were summarized to find the different types of needs.

Findings

There are three different types of needs for improvement: needs of function, needs of technology and needs of experience. These types can be further divided into six subtypes: richness of function, feasibility of function, easiness of technology, stableness of technology, optimization of experience and customization of experience. Besides the richness of function, the feasibility of function has received the most attention from users.

Originality/value

Most studies on m-library user needs have only focused on a method of quantitative research based on questionnaire surveys. This study, however, is the first to apply text mining methods for large-scale user opinion texts, which place more focus on user needs and inspire libraries and app providers to further improve their services.

Details

Library Hi Tech, vol. 37 no. 3
Type: Research Article
ISSN: 0737-8831

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Article
Publication date: 9 December 2024

Zhao Peng and Kong Dejun

The aim was to investigate the effect of normal load on the tribological performance of laser cladded FeCoCrMoSi amorphous coating, which might choose the appropriate normal load…

26

Abstract

Purpose

The aim was to investigate the effect of normal load on the tribological performance of laser cladded FeCoCrMoSi amorphous coating, which might choose the appropriate normal load for the friction reduction and wear resistance.

Design/methodology/approach

A FeCoCrMoSi amorphous coating was prepared on 45 steel using laser cladding, and the tribological performance of obtained coating under the different normal loads was investigated using a ball-on-disk tribometer.

Findings

The FeCoCrMoSi amorphous coating is composed of M23C6, Co6Mo6C2 and amorphous phases, where the M23C6 hard phase enhances the coating hardness to increase the wear resistance and the Co6Mo6C2 with the vein shape forms the strong mechanical interlock to play the role of friction reduction. The average coefficients of friction of containing amorphous FeCoCrMoSi coating under the normal loads of 3, 4 and 5 N are 0.68, 0.65 and 0.53, respectively, and the corresponding wear rates are 17.7, 23.9 and 21.9 µm3•N−1•mm−1, respectively, showing that the appropriate normal load is beneficial for improving its friction reduction and wear resistance. The wear mechanism is composed of adhesive wear, abrasive wear and oxidative wear, which is attributed to the high hardness of amorphous coating by the amorphous phase.

Originality/value

The FeCoCrMoSi amorphous coating was first applied for the improvement of 45 steel, and the effect of normal load on its tribological performance was investigated.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-08-2024-0304/

Details

Industrial Lubrication and Tribology, vol. 77 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 1 January 2025

Long Zhang, Kaiwei Zhang and Dejun Kong

The purpose of this study to investigate the high temperature tribological performances of CrN and CrAlN coatings on AISI H13 steel, which was beneficial to improve the wear…

20

Abstract

Purpose

The purpose of this study to investigate the high temperature tribological performances of CrN and CrAlN coatings on AISI H13 steel, which was beneficial to improve the wear resistance of hot work molds.

Design/methodology/approach

Arc ion plating was used to deposit the CrN and CrAlN coatings on AISI H13 steel, and the tribological performances of CrN and CrAlN coatings were evaluated using a ball-on-plate wear tester.

Findings

The average coefficients of friction and wear rate of CrAlN coating in the normal wear period are 0.33 and 5.34 × 10–9 mm3·N–1·mm–1, respectively, which are lower than those of CrN coating, exhibiting that the outstanding friction reduction. The formations of Cr and Al oxides during the wear process are the main factor in enhancing the tribological performance of CrAlN coating.

Originality/value

CrN and CrAlN coatings were applied for hot work molds, and their tribological performances were comparatively investigated.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-09-2024-0359/

Details

Industrial Lubrication and Tribology, vol. 77 no. 2
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 27 February 2020

Kong Dejun and Chen Haixiang

The purpose of this paper is to investigate the effects of laser power on the electrochemical corrosion performance in 3.5% NaCl, 0.1 M H2SO4 and 0.1 M NaOH solutions, which…

173

Abstract

Purpose

The purpose of this paper is to investigate the effects of laser power on the electrochemical corrosion performance in 3.5% NaCl, 0.1 M H2SO4 and 0.1 M NaOH solutions, which provided an experimental basis for the application of Al–Ti–Ni amorphous coating in marine environment.

Design/methodology/approach

Amorphous Al–Ti–Ni coatings were fabricated on S355 structural steel by laser thermal spraying (LTS) at different laser powers. The surface and cross-section morphologies, chemical element distribution, phases and crystallization behaviors of obtained coatings were analyzed using a scanning electron microscope, energy-dispersive X-ray spectroscope, X-ray diffraction and differential scanning calorimetry, respectively. The effects of laser power on the electrochemical corrosion performances of Al–Ti–Ni coatings in 3.5% NaCl, 0.1 M H2SO4 and 0.1 M NaOH solutions were investigated using an electrochemical workstation.

Findings

The crystallization temperature of Al–Ti–Ni coatings fabricated at the laser power of 1,300 and 1,700 W is ∼520°C, whereas that fabricated at the laser power of 1,500 W is ∼310°C. The coatings display excellent corrosion resistance in 3.5% NaCl and 0.1 M NaOH solutions, while a faster dissolution rate in 0.1 M H2SO4 solution. The coatings fabricated at the laser power of 1,300 and 1,700 W present the better electrochemical corrosion resistance in 3.5% NaCl and 0.1 M NaOH solutions, whereas that fabricated at the laser power of 1,500 W exhibits the better electrochemical corrosion resistance in 0.1 M H2SO4 solution.

Originality/value

In this work, Al-wire-cored Ti–Ni powder was first on S355 steel with the laser power of 1,300, 1,500 and 1,700 W, and the effects of laser power on the electrochemical corrosion performance in 3.5% NaCl, 0.1 M H2SO4 and 0.1 M NaOH solutions were investigated using an electrochemical workstation.

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Article
Publication date: 31 May 2022

Hu Yan and Kong Dejun

This paper aims to investigate the effects of Cr and Ta additions on the friction performance and corrosion-wear mechanism of Fe90-Al2O3 coating in 3.5% NaCl solution.

163

Abstract

Purpose

This paper aims to investigate the effects of Cr and Ta additions on the friction performance and corrosion-wear mechanism of Fe90-Al2O3 coating in 3.5% NaCl solution.

Design/methodology/approach

Cr and Ta reinforced Fe90-Al2O3 coatings were prepared on Q235 steel by laser cladding. The effects of Cr and Ta addition on the coefficient of friction (COF) and wear rate of Fe90-Al2O3 coating were investigated using a friction tester, and the wear model was established to discuss its corrosion-wear mechanism.

Findings

The average COFs of Fe90-Al2O3, Fe90-Al2O3-10%Cr and Fe90-Al2O3-10%Ta coatings in 3.5% NaCl solution are 0.57, 0.42 and 0.75, respectively, and the corresponding wear rates are 9.42 × 10−7, 5.31 × 10−7 and 7.02 × 10−7 mm3 s−1 N−1, respectively. The corrosion-wear resistance of Fe90-Al2O3-10%Cr coating is the best among the three kinds of coatings, in which the additions of Cr and Ta play a role in solid solution strengthening.

Originality/value

The Fe90-Al2O3 coating was strengthened by the additions of Cr and Ta to improve its corrosion-wear resistance in 3.5% NaCl solution.

Details

Anti-Corrosion Methods and Materials, vol. 69 no. 4
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 18 October 2021

Yan Hu and Dejun Kong

This paper aims to improve the friction reduction and wear resistance of Fe90 alloy coating by the addition of Al2O3.

171

Abstract

Purpose

This paper aims to improve the friction reduction and wear resistance of Fe90 alloy coating by the addition of Al2O3.

Design/methodology/approach

Fe90 alloy coatings with the different Al2O3 mass fractions were prepared on Q235 steel by laser cladding (LC). The morphologies, phases and hardness of Fe90 alloy coating were analyzed using a scanning electron microscope (SEM), X-ray diffraction (XRD) and microhardness tester, respectively. The effects of Al2O3 mass fraction on the coefficient of friction (COF) and wear rates of Fe90 alloy coating were investigated using a friction tester, and the wear model was built to discuss the wear mechanism of Al2O3-reinforced Fe90 alloy coating.

Findings

The results show that the large number of Fe carbides is generated on the Fe90–Al2O3 coatings by the effect of laser high energy, and the hardness of Fe90–coating is 806 HV0.5, which is 4.48 times of substrate. The average COFs of Fe90–Al2O3 alloy coatings decrease from 0.73 to 0.55, and the wear rates are also reduced from 447.78 to 274.63 µm3•s–1•N–1 by the addition of Al2O3. The Fe90–6% Al2O3 coating presents the highest wear resistance among the three kinds of coatings, and the wear mechanism is abrasive wear and micro-cutting wear.

Originality/value

The Al2O3-reinforced Fe90 alloy coating was first fabricated by laser cladding, and the effect of Al2O3 on the friction-wear performance of Fe90 alloy coating was investigated.

Details

Industrial Lubrication and Tribology, vol. 73 no. 10
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 14 February 2019

Li Jiahong and Kong Dejun

The purpose of this paper is to improve the salt spray corrosion and electrochemical corrosion performances of H13 hot work mould steel, Cr–Ni coatings with the different Cr and…

166

Abstract

Purpose

The purpose of this paper is to improve the salt spray corrosion and electrochemical corrosion performances of H13 hot work mould steel, Cr–Ni coatings with the different Cr and Ni mass ratios are fabricated using a laser cladding (LC), which provides an experimental basis for the surface modification treatment of H13 steel.

Design/methodology/approach

Cr–Ni coatings with the different Cr and Ni mass ratios were firstly fabricated on H13 hot work mould steel using a laser cladding (LC). The salt spray corrosion (SSC) and electrochemical corrosion performances of Cr–Ni coatings in 3.5 Wt.% NaCl solution were investigated to analyze the corrosion mechanism, and the effect of mass ratios of Cr and Ni on their corrosion mechanism was discussed.

Findings

The laser cladded Cr–Ni coatings with the different Cr and Ni mass ratios are composed of Cr–Ni compounds, which are metallurgically combined with the substrate. The SSC resistance of Cr–Ni coating with the Cr and Ni mass ratios of 24:76 is the highest. The electrochemical corrosion resistance of Cr–Ni coating with the Cr and Ni mass ratio of 24:76 is the best among the three kinds of coatings.

Originality/value

In this study, the corrosion resistance of laser cladded Cr–Ni coatings with the Cr and Ni mass ratios of 17: 83, 20: 80 and 24: 76 was first evaluated using salt spray corrosion (SSC) and electrochemical tests, and the effect of mass ratios of Cr and Ni on their corrosion mechanism was discussed.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 27 May 2024

Sana (Shih‐chi) Chiu, Dejun Tony Kong and Nikhil Celly

This study aims to address the question of why managers make different decisions in employee downsizing when their firms face external threats. Our research intends to shed light…

142

Abstract

Purpose

This study aims to address the question of why managers make different decisions in employee downsizing when their firms face external threats. Our research intends to shed light on whether and how CEOs' cognition (motivational attributes associated with regulatory focus) influences their decision-making and firms’ strategic actions on downsizing under high resource scarcity in the industry environment.

Design/methodology/approach

We used a longitudinal panel of 5,544 firm-year observations of US firms from 2003 to 2015 to test our conceptual model. The data was obtained from various sources, including corporate earnings call transcripts and archival databases. We used panel logistic regressions with both fixed and random effects in our research design.

Findings

Our results suggest that CEOs' motivational attributes could influence their employee downsizing decisions in response to external threats. We find that CEOs who are more promotion-focused (a stronger drive towards achieving ideals) are less likely to lay off employees during high resource scarcity. Conversely, CEOs with a higher prevention focus (a greater concern for security) do not have a meaningful impact on employee downsizing during periods of external resource scarcity.

Originality/value

Previous research has argued that a significant external threat would diminish individuals' impact on firm strategies and outcomes. Our findings challenge this idea, indicating that CEOs with a stronger drive towards achieving ideals are less inclined to lay off employees when resources are scarce in the environment. This study contributes to behavioral strategy research by providing new insights into how upper echelons’ cognition can influence their decision-making and firms’ employee downsizing.

Details

Management Decision, vol. 62 no. 11
Type: Research Article
ISSN: 0025-1747

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Article
Publication date: 14 June 2011

Dejun Chen, Zude Zhou, Yingzhe Ma and D.T. Pham

The purpose of this paper is to create a platform framework based on agent for virtual enterprise (VE) with the characteristic of supply chain by adopting multi‐agent technology.

779

Abstract

Purpose

The purpose of this paper is to create a platform framework based on agent for virtual enterprise (VE) with the characteristic of supply chain by adopting multi‐agent technology.

Design/methodology/approach

According to the system hierarchy theory and the features of VE with the characteristic of supply chain, the conception and organization structure of supply chain‐oriented VE are proposed. Combined with characters of multi‐agent, a platform framework based on agent for VE with the characteristic of supply chain is created. Aiming at complexity of net node of running platform framework, two‐layer architecture mode, which are information alternation layer and basic function layer inside net node based on agent, are designed. The modes are proved to be reasonable in the management of the system and networks resources.

Findings

The theory base of realization of the VE based on agent with the characteristic of supply chain is found.

Research limitations/implications

The reasonable basic function design of various agents are main limitations.

Practical implications

The paper presents a very useful tool for the operation and management of VE.

Originality/value

A new approach and scheme for VE with the characteristic of supply chain is presented. This paper is aimed at researchers and engineers.

Details

Kybernetes, vol. 40 no. 5/6
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 17 September 2021

Wang Zhizhong, Han Chao, Guosheng Huang, Han Bin and Han Bin

The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient…

505

Abstract

Purpose

The deposition of particles onto a substrate during the cold spraying (CS) process relies on severe plastic deformation, so there are various micro-defects induced by insufficient deformation and severe crushing. To solve the problems, many post-treat techniques have been used to improving the quality by eliminating the micro-defects. This paper aims to help scholars and engineers in this field a better and systematic understand of CS technology by summarizing the post-treatment technologies that have been investigated recently years.

Design/methodology/approach

This review summarizes the types of micro-defects and introduces the effect of micro-defects on the properties of CS coating/additive manufactured, illustrates the post-treatment technologies and its effect on the microstructure and performances, and finally outlooks the future development trends of post-treatments for CS.

Findings

There are significant discoveries in post-treatment technology to change the performance of cold spray deposits. There are also many limitations for post-treatment methods, including improved performance and limitations of use. Thus, there is still a strong requirement for further improvement. Hybrid post-treatment may be a more ideal method, as it can eliminate more defects than a single method. The proposed ultrasonic impact treatment could be an alternative method, as it can densify and flatten the CS deposits.

Originality/value

It is the first time to reveal the influence factors on the performances of CS deposits from the perspective of microdefects, and proposed corresponding well targeted post-treatment methods, which is more instructive for improving the performances of CS deposits.

Details

Rapid Prototyping Journal, vol. 28 no. 2
Type: Research Article
ISSN: 1355-2546

Keywords

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