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1 – 10 of 38
Article
Publication date: 1 August 2016

Yong Yin, Jian Zhou, Chaoyong Zhang and Dejun Chen

The purpose of this paper is to discuss an adaptive SLA mechanism for service sharing in virtual environment, which can organize and govern QoS items in terms of service execution…

Abstract

Purpose

The purpose of this paper is to discuss an adaptive SLA mechanism for service sharing in virtual environment, which can organize and govern QoS items in terms of service execution time, reliability, and availability, and provides a common understanding about services, responsibilities, priorities, guarantees and warranties-related virtual cooperative issues.

Design/methodology/approach

The management framework for SLA is introduced, based on which the whole process including SLA contract, adaptive SLA negotiation strategy, SLA deployment and SLA assessment are discussed, and the prototype is implemented in the cloud manufacturing platform.

Findings

A proposed SLA framework for service sharing in virtual environments is given; electronic contracts are designed in the framework for encapsulating measurable aspects of service level agreements so as to provide common understanding about the service; and an improved SLA negotiation strategy with three phases is presented for the dynamicity of the virtual services.

Originality/value

The paper presents a very useful adaptive SLA mechanism for service sharing in virtual environments that can be utilized in concurrent or future advanced manufacturing modes.

Details

Kybernetes, vol. 45 no. 7
Type: Research Article
ISSN: 0368-492X

Keywords

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.

778

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

Keywords

Article
Publication date: 17 October 2008

Dejun Chen, Zude Zhou and D.T. Pham

The purpose of this paper is to create a model of role‐based access control (RBAC) for virtual enterprise (VE).

415

Abstract

Purpose

The purpose of this paper is to create a model of role‐based access control (RBAC) for virtual enterprise (VE).

Design/methodology/approach

An access control model for security and management of VE is presented by integrating generic structure of VE and applying the principles of RBAC. In addition, the application of the model to a supply chain oriented VE illustrates that a general access control scheme can ensure the running of VE.

Findings

A theory base of access control for the realization of the VE is found.

Originality/value

The paper provides a very useful new model of access control for VE. This paper is aimed at researchers and engineers.

Details

Kybernetes, vol. 37 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 17 October 2008

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

The purpose of this paper is to create a model of role‐based access control (RBAC) based access control for virtual enterprise (VE).

357

Abstract

Purpose

The purpose of this paper is to create a model of role‐based access control (RBAC) based access control for virtual enterprise (VE).

Design/methodology/approach

An access control model for security and management of VE is presented by integrating generic structure of VE and applying the principles of RBAC. In addition, the application of the model to a supply chain‐oriented VE illustrates that a general access control scheme can ensure the running of VE.

Findings

A theory base of access control for the realization of the VE is found.

Originality/value

The paper presents a very useful new model of access control for VE. This paper is aimed at researchers and engineers.

Details

Kybernetes, vol. 37 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 17 October 2008

Dejun Chen, Zude Zhou and Rui Hu

The purpose of this paper is to create the inventory scheduling model for supply chain system.

961

Abstract

Purpose

The purpose of this paper is to create the inventory scheduling model for supply chain system.

Design/methodology/approach

Aiming at the problems of analysis and modeling of multi‐agent system, an agent‐oriented Petri net (AOPN) model is proposed by introducing the characteristics of agent based on Petri net, and formalization definition of AOPN is presented. Combined with the inventory scheduling in supply chain system, inventory scheduling model based on AOPN is constructed. On the basis of the inventory scheduling model, its program model is designed. Then the reachability of the inventory scheduling model is analyzed and its soundness is verified.

Findings

The AOPN model and inventory scheduling model based on AOPN in supply chain system are found.

Research limitations/implications

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

Practical implications

A very useful tool of analysis for the modeling of inventory scheduling in supply chain system.

Originality/value

The paper presents a new modeling method of inventory scheduling in supply chain system. This paper is aimed at researchers and engineers.

Details

Kybernetes, vol. 37 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

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…

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.

Article
Publication date: 6 June 2018

Chen Haixiang and Kong Dejun

In this study, an amorphous Al-Ti-Ni coating was fabricated on S355 steel using an arc spraying, and its corrosion behavior immersed in 3.5 per cent NaCl solution for 720 h was…

Abstract

Purpose

In this study, an amorphous Al-Ti-Ni coating was fabricated on S355 steel using an arc spraying, and its corrosion behavior immersed in 3.5 per cent NaCl solution for 720 h was discussed, which provided an experimental basis for the application of arc sprayed Al-Ti-Ni coating on S355 steel on marine platform.

Design/methodology/approach

An amorphous Al-Ti-Ni coating was sprayed on S355 structural steel using an arc spraying. The surface-interface morphologies, chemical element compositions and phases of the obtained Al-Ti-Ni coating were analyzed using a scanning electron microscope, energy dispersive spectrometer and X-ray diffractometer, respectively. The distributions of chemical elements on the coating surface and interface were analyzed using an energy spectrum scanning; the bonding mechanism between the coating and the substrate was also discussed.

Findings

Financial support for this research by the Key Research and Development Project of Jiangsu Province (BE2016052).

Originality/value

In this study, an amorphous Al-Ti-Ni coating was fabricated on S355 steel using an arc spraying, its corrosion behavior immersed in 3.5 per cent 25 NaCl solution for 720 h was discussed.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 3
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 10 July 2019

Xiaoyu Wang, Jia Zhai, Dejun Xie and Jingjing Jiang

The purpose of this paper is to investigate the impact of Federal Open Market Committee (FOMC) meetings and the changes of the target rates on stock market uncertainty.

Abstract

Purpose

The purpose of this paper is to investigate the impact of Federal Open Market Committee (FOMC) meetings and the changes of the target rates on stock market uncertainty.

Design/methodology/approach

Multivariate regression analysis is applied to the historical data of VIX, FOMC meetings and target rates. Subtle relations are revealed by further categorizing the FOMC meetings into being scheduled and unscheduled and distinguishing the signs of the changes in VIX and target rates. CPI and the prime rate are used for robustness test.

Findings

The authors first examine the relation between FOMC meetings and target surprises; the results indicate that unscheduled FOMC meetings heavily impact the target surprises. Then, the authors investigate the relation between FOMC meetings and VIX changes; the results show that both unscheduled and scheduled FOMC meetings impact VIX, where the impacts of scheduled FOMC meetings are more substantial. The authors also analyze the responses of VIX to the target surprises, and the results reveal that there is an asymmetric effect of target surprises on VIX, where the influences of the scheduled positive target surprises are more significant. Finally, by examining the relation between the FOMC meeting and the risk-neutral density of the VIX option, the authors conclude that both KURT and SKEW are more affected by unscheduled FOMC meetings.

Originality/value

Deeper dimensions of the relations between VIX, FOMC meetings and target rates are analyzed and more insightful understandings of such relations are gained.

Details

China Finance Review International, vol. 10 no. 1
Type: Research Article
ISSN: 2044-1398

Keywords

Article
Publication date: 16 August 2019

Zhou Weitong and Kong Dejun

This paper aims to enhance the corrosive wear and electrochemical corrosion of Ti–6Al–4V alloy.

Abstract

Purpose

This paper aims to enhance the corrosive wear and electrochemical corrosion of Ti–6Al–4V alloy.

Design/methodology/approach

A CoCrAlYTaSi alloy coating was fabricated on Ti–6Al–4V alloy using a laser thermal spraying (LTS). The surface and cross-section morphologies, chemical elements, phases and bonding strength of the obtained coating were analyzed using a scanning electron microscope, energy dispersive spectroscope, X-ray diffraction and scratch test, respectively, The corrosive wear and electrochemical corrosion of CoCrAlYTaSi coating in 3.5 Wt.% NaCl solution were investigated using a wear tester and electrochemical workstation, respectively.

Findings

The average coefficient of frictions (COFs) of CoCrAlYTaSi coating under the wear loads of 2, 4 and 6 N are 1.31, 1.02 and 0.88, respectively; and the corresponding wear rates are 0.66 × 10−4, 1.10 × 10−4 and 1.30 × 10−4 mm3·N–1·m–1, respectively. The wear mechanism under the wear load of 2 N is abrasive wear, while those under the wear loads of 4 and 6 N are adhesive wear and abrasive wear. The charge transfer resistance of CoCrAlYTaSi coating is 5.368 × 105 Ω·cm2, higher than 2.193 × 105 of the substrate.

Originality/value

In this study, a CoCrAlYTaSi coating was firstly fabricated on Ti–6Al–4V alloy using a LTS. Its corrosive wear and electrochemical corrosion in 3.5 Wt.% NaCl solution were investigated, which played a protective role of corrosive wear on Ti–6Al–4V alloy.

Details

Anti-Corrosion Methods and Materials, vol. 66 no. 5
Type: Research Article
ISSN: 0003-5599

Keywords

Article
Publication date: 17 July 2018

Yan Baoxu and Kong Dejun

The amorphous Al-Ni-Fe-Gd coatings were fabricated to improve anti-corrosion performance of offshore platforms.

Abstract

Purpose

The amorphous Al-Ni-Fe-Gd coatings were fabricated to improve anti-corrosion performance of offshore platforms.

Design/methodology/approach

The amorphous Al-Ni-Fe-Gd coatings were first fabricated on S355 steel using the laser thermal spraying.

Findings

The amorphous forming capability and corrosion resistance increases with the laser powers increasing.

Research Limitations/implications

The amorphous Al-Ni-Fe-Gd coatings were applied on S355 steel of offshore platforms to increase its long-term heavy and anti-corrosion protection.

Originality/value

The amorphous Al-Ni-Fe-Gd coatings were first fabricated using a laser thermal spraying, improving its anti-corrosion.

Details

Anti-Corrosion Methods and Materials, vol. 65 no. 4
Type: Research Article
ISSN: 0003-5599

Keywords

1 – 10 of 38