Search results

1 – 10 of 74
Per page
102050
Citations:
Loading...
Access Restricted. View access options
Article
Publication date: 16 January 2017

Renwei Liu, Zhiyuan Wang, Todd Sparks, Frank Liou and Cedo Nedic

This paper aims to investigate a stereo vision-based hybrid (additive and subtractive) manufacturing process using direct laser metal deposition, computer numerical control (CNC…

565

Abstract

Purpose

This paper aims to investigate a stereo vision-based hybrid (additive and subtractive) manufacturing process using direct laser metal deposition, computer numerical control (CNC) machining and in-process scanning to repair metallic components automatically. The focus of this work was to realize automated alignment and adaptive tool path generation that can repair metallic components after a single setup.

Design/methodology/approach

Stereo vision was used to detect the defect area for automated alignment. After the defect is located, a laser displacement sensor is used to scan the defect area before and after laser metal deposition. The scan is then processed by an adaptive algorithm to generate a tool path for repairing the defect.

Findings

The hybrid manufacturing processes for repairing metallic component combine the advantages of free-form fabrication from additive manufacturing with the high-accuracy offered by CNC machining. A Ti-6Al-4V component with a manufacturing defect was repaired by the proposed process. Compared to previous research on repairing worn components, introducing stereo vision and laser scanning dramatically simplifies the manual labor required to extract and reconstruct the defect area’s geometry.

Originality/value

This paper demonstrates an automated metallic component repair process by integrating stereo vision and a laser displacement sensor into a hybrid manufacturing system. Experimental results and microstructure analysis shows that the defect area could be repaired feasibly and efficiently with acceptable heat affected zone using the proposed approach.

Details

Rapid Prototyping Journal, vol. 23 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

Access Restricted. View access options
Article
Publication date: 3 September 2024

Yinghu Wang, Zhiyuan Wang and Jianyan Xu

High-nitrogen steel is a common material for the manufacture of drilling equipment such as drill collars. However, its poor surface properties often limit its applications. The…

35

Abstract

Purpose

High-nitrogen steel is a common material for the manufacture of drilling equipment such as drill collars. However, its poor surface properties often limit its applications. The purpose of this paper is to find a way to enhance the surface performance of high-nitrogen steel, which is expected to improve the wear resistance of high-nitrogen steel.

Design/methodology/approach

The CoCrNi and CoCrFeNi medium-entropy alloy (MEA) coatings were prepared on high-nitrogen steel substrate by laser cladding technology. The microstructure, phase composition and element distribution of the fabricated coatings were investigated using scanning electronic microscopy, electron backscatter diffraction and X-ray diffraction. The phase structure, phase stability and structural stability of the CoCrNi and CoCrFeNi MEAs were investigated in combination with phase diagram calculation and molecular dynamics. Then the wear tests were carried out for coatings.

Findings

The results show that both prepared MEA coatings have good quality and contain a single face-centered cubic phase. The wear performance of MEA coatings is improved by the refinement of grain size and the increase of dislocation density. Due to the addition of Fe atoms, the lattice distortion of the CoCrFeNi system increased, resulting in a higher dislocation density of the coating. Cr atoms in the CoCrFeNi system are the largest, and the local lattice distortions induced by them are greater. Through this study, MEA coatings with high hardness can be expanded to drilling field applications.

Originality/value

CoCrFeNi and CoCrNi MEA coatings were successfully prepared on the surface of high-nitrogen steel for the first time without obvious defects. The micromorphology and grain orientation of the different kinds of coatings were discussed in detail. The hardness-strengthening mechanism and structure stability of the coatings were illustrated by experiments and molecular dynamics simulations.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-04-2024-0116/

Details

Industrial Lubrication and Tribology, vol. 76 no. 7/8
Type: Research Article
ISSN: 0036-8792

Keywords

Access Restricted. View access options
Article
Publication date: 4 November 2019

Zhiyuan Wang, Jagdeep Singh-Ladhar and Howard Davey

This paper aims to examine the indirect tax reform process in China. Specifically, it examines the reform of business tax to value-added tax. Inefficiencies within the new tax…

1271

Abstract

Purpose

This paper aims to examine the indirect tax reform process in China. Specifically, it examines the reform of business tax to value-added tax. Inefficiencies within the new tax system are identified and discussed. The “business tax to value-added tax” reform was seen as an essential element in promoting the economic transition and stimulating the service industries (Jin and Jin, 2013).

Design/methodology/approach

The paper uses archival and current literature. In undertaking the study, the different periods of indirect tax are examined, prior to 1994, 1994-2012, the changes from 2012 culminating in the new 2017 regime. Attributes of “good” value-added tax (VAT) systems are covered as well as a comparison with New Zealand’s goods and services tax (GST).

Findings

The paper finds that to align with the international trend of indirect tax development and more efficiently accomplish the economic transition China needs to build a more neutral VAT system with fewer reduced rates and exemptions and the tax system have created tax inefficiencies and increased the compliance cost. VAT is imposing an increasingly significant impact on China’s national economy and industrial structure as well as accountants.

Originality/value

This is the first study that analyses the indirect tax reforms that are currently being implemented in China and as such has lessons for China but also for VAT/GST in general. We should not forget how special New Zealand’s GST is and the clarity of focus of those who implemented it!

Details

Pacific Accounting Review, vol. 31 no. 4
Type: Research Article
ISSN: 0114-0582

Keywords

Access Restricted. View access options
Article
Publication date: 5 July 2022

Debiao Meng, Shiyuan Yang, Chao He, Hongtao Wang, Zhiyuan Lv, Yipeng Guo and Peng Nie

As an advanced calculation methodology, reliability-based multidisciplinary design optimization (RBMDO) has been widely acknowledged for the design problems of modern complex…

768

Abstract

Purpose

As an advanced calculation methodology, reliability-based multidisciplinary design optimization (RBMDO) has been widely acknowledged for the design problems of modern complex engineering systems, not only because of the accurate evaluation of the impact of uncertain factors but also the relatively good balance between economy and safety of performance. However, with the increasing complexity of engineering technology, the proposed RBMDO method gradually cannot effectively solve the higher nonlinear coupled multidisciplinary uncertainty design optimization problems, which limits the engineering application of RBMDO. Many valuable works have been done in the RBMDO field in recent decades to tackle the above challenges. This study is to review these studies systematically, highlight the research opportunities and challenges, and attempt to guide future research efforts.

Design/methodology/approach

This study presents a comprehensive review of the RBMDO theory, mainly including the reliability analysis methods of different uncertainties and the decoupling strategies of RBMDO.

Findings

First, the multidisciplinary design optimization (MDO) preliminaries are given. The basic MDO concepts and the corresponding mathematical formulas are illustrated. Then, the procedures of three RBMDO methods with different reliability analysis strategies are introduced in detail. These RBMDO methods were proposed for the design optimization problems under different uncertainty types. Furtherly, an optimization problem for a certain operating condition of a turbine runner blade is introduced to illustrate the engineering application of the above method. Finally, three aspects of future challenges for RBMDO, namely, time-varying uncertainty analysis; high-precision surrogate models, and verification, validation and accreditation (VVA) for the model, are discussed followed by the conclusion.

Originality/value

The scope of this study is to introduce the RBMDO theory systematically. Three commonly used RBMDO-SORA methods are reviewed comprehensively, including the methods' general procedures and mathematical models.

Access Restricted. View access options
Book part
Publication date: 12 November 2016

Qihao He

Due to climate change and an increasing concentration of the world’s population in vulnerable areas, how to manage catastrophe risk efficiently and cover disaster losses fairly is…

Abstract

Purpose

Due to climate change and an increasing concentration of the world’s population in vulnerable areas, how to manage catastrophe risk efficiently and cover disaster losses fairly is still a universal dilemma.

Methodology

This paper applies a law and economic approach.

Findings

China’s mechanism for managing catastrophic disaster risk is in many ways unique. It emphasizes government responsibilities and works well in many respects, especially in disaster emergency relief. Nonetheless, China’s mechanism which has the vestige of a centrally planned economy needs reform.

Practical Implications

I propose a catastrophe insurance market-enhancing framework which marries the merits of both the market and government to manage catastrophe risks. There are three pillars of the framework: (i) sustaining a strong and capable government; (ii) government enhancement of the market, neither supplanting nor retarding it; (iii) legalizing the relationship between government and market to prevent government from undermining well-functioning market operations. A catastrophe insurance market-enhancing framework may provide insights for developing catastrophe insurance in China and other transitional nations.

Originality

First, this paper analyzes China’s mechanism for managing catastrophic disaster risks and China’s approach which emphasizes government responsibilities will shed light on solving how to manage catastrophe risk efficiently and cover disaster losses fairly. Second, this paper starts a broader discussion about government stimulation of developing catastrophe insurance and this framework can stimulate attention to solve the universal dilemma.

Details

The Political Economy of Chinese Finance
Type: Book
ISBN: 978-1-78560-957-2

Keywords

Access Restricted. View access options
Article
Publication date: 8 January 2025

Xiaodong Yu, Zhiyuan Lan, Xiuli Meng, Peng Wang, Yanlong Lin, Boyu Du, Mingjuan Shao, Xinyi Yang, Ruichun Dai, Wentao Jia, Junfeng Wang, Hui Jiang and Jian-Hua Jiao

The purpose of this study is to investigate the influence of rotational speed on the oil film stability of the hydrostatic rotary table having double rectangular oil pads. The oil…

8

Abstract

Purpose

The purpose of this study is to investigate the influence of rotational speed on the oil film stability of the hydrostatic rotary table having double rectangular oil pads. The oil film stability is evaluated based on the oil film stiffness under constant load condition and the displacement response amplitude of the oil film under disturbance load condition.

Design/methodology/approach

The oil film stability theoretical equations of the double rectangular oil cavity are deduced such as oil film stiffness, damping and dynamic equations. A simulation model is developed to analyze the relationship among oil film temperature, oil film pressure fields and oil film stability. The user-defined function programs are used to control the rotational speed, lubricant viscosity and oil film thickness during the simulation. In addition, an experimental rig is built to test the simulation results.

Findings

This study shows that oil film stability decreases with increasing rotational speed under constant load and disturbance load. The trend of oil film stability decreased slowly within 30 r/min, and then rapidly. However, since the hydrodynamic pressure effect, the decrease rate of stability is mitigated under constant load and high rotational speeds.

Originality/value

The conclusions can provide a theoretical basis for improving the oil film stability of machines with similar hydrostatic support structure.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-07-2024-0267/

Details

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

Keywords

Access Restricted. View access options
Article
Publication date: 16 November 2022

Zhenkun Liu, Ping Jiang, Jianzhou Wang, Zhiyuan Du, Xinsong Niu and Lifang Zhang

This study/paper aims to reach the core objective of hospitality order cancellation prediction (HOCP), that is, to identify potential cancellers from many customer bases, thereby…

698

Abstract

Purpose

This study/paper aims to reach the core objective of hospitality order cancellation prediction (HOCP), that is, to identify potential cancellers from many customer bases, thereby enhancing the effectiveness of customer retention campaigns. However, few studies have focused on predicting hospitality order cancellation.

Design/methodology/approach

A novel profit-driven model for predicting hospitality order cancellation is proposed to bridge this research gap. The authors construct profit-driven extreme gradient boosting (XGBoost) based on a grid search on HOCP to maximize profit by selecting optimal hyperparameters of XGBoost.

Findings

Real-world data set is analyzed, and the proposed model yields more profits than other predictive models. Sensitivity analysis proves that the proposed model is robust to the key hyperparameter and application scenario. Furthermore, some preventive measures based on visual analysis results are provided to reduce the cancelled probability of orders.

Research limitations/implications

This research will help hotel managers to transfer the modeling goal to profit orientation and encourage relevant researchers to interpret the prediction results of models for hotel order cancellation prediction in a post hoc manner. Besides, the proposed model can be applied to various enterprises with different average order profits and help managers optimize revenue management.

Originality/value

This research expands the relevant literature and offers guidance for predicting hospitality order cancellation from a profit-driven perspective at the customer level. The proposed model can provide macro-control to hotel managers and obtain the most satisfactory profits in micro-control.

Details

International Journal of Contemporary Hospitality Management, vol. 35 no. 6
Type: Research Article
ISSN: 0959-6119

Keywords

Access Restricted. View access options
Article
Publication date: 24 September 2024

Zifeng Wang, Zhiyuan Ning and Fei Wu

The purpose of this study is to provide evidence that government financing behavior has an impact on the outward foreign direct investment (OFDI) of enterprises.

55

Abstract

Purpose

The purpose of this study is to provide evidence that government financing behavior has an impact on the outward foreign direct investment (OFDI) of enterprises.

Design/methodology/approach

This paper uses debt data from local government financing vehicles to measure the local government debt in China. Based on the data of listed manufacturing firms in China from 2010 to 2018, this paper uses the Tobit model to verify the impact of local government debt and firms' OFDI.

Findings

The results indicate that local government debt impedes firms' OFDI, with a more pronounced impact on state-owned enterprises (SOEs) and those with higher political connections. Furthermore, our study suggests that the dampening effect of local governments on firms' OFDI is mitigated in regions following the implementation of the Local Government Debt Management Act.

Originality/value

This study verifies the negative impact of local government debt activity on firms' overseas investments. This is not due to debt crowding out, but rather to the fact that local governments prefer to keep resources locally to stimulate the economy. This paper offers novel insights into the theoretical mechanisms by which local government behavior influences firms' investment activities in emerging markets.

Details

International Journal of Emerging Markets, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1746-8809

Keywords

Access Restricted. View access options
Article
Publication date: 30 June 2020

Zhiyuan Li, Lijuan Zheng, Chengyong Wang, Xin Huang and Jiechi Xie

The flexible printed circuit (FPC) board with the characteristic of light and thin strengthened confronted the growing miniaturization requirements of the electronic product and…

164

Abstract

Purpose

The flexible printed circuit (FPC) board with the characteristic of light and thin strengthened confronted the growing miniaturization requirements of the electronic product and the popularity of wearable devices. The reliability of circuit could be influenced by the hole quality of FPC, such as burrs, which is one of the major problem in FPC.

Design/methodology/approach

In this paper, micro-drill with a diameter of 0.1 mm was used to drill the double-sided flexible copper clad laminate. The thrust force, the burr and tool wear were investigated. The influencing factors of the height of the burrs were studied. The relationship between the thrust force and the height of the burrs was also explored. Finally, the formation mechanism of burrs was analyzed.

Findings

The entrance burrs were usually less than the exit burrs. The burr height increased with the feed per rotation. The height of the burr increased with the increase of the thrust force for the plastic deformation of the copper foil was dominant. The abrasion of the drill gave rise to increase the height of burr. In micro-hole drilling, the growth of burrs can be suppressed effectively by reducing the clearance between the FPC and the backup plate. The thrust force would be controlled in a certain range to reduce the burr with specific drilling parameters. There existed a certain relationship of Gaussian distribution between the height of the burrs and the thrust force of FPC.

Originality/value

The reliability of the integrated circuit was directly affected by the burrs of the FPC. This research on the formation mechanism of FPC burrs and forecast of burr height provided a firm foundation for further work in the area of improvement of the micro-hole quality.

Details

Circuit World, vol. 46 no. 4
Type: Research Article
ISSN: 0305-6120

Keywords

Access Restricted. View access options
Article
Publication date: 23 September 2021

Jianing Wang, Jieshi Chen, Zhiyuan Zhang, Peilei Zhang, Zhishui Yu and Shuye Zhang

The purpose of this article is the effect of doping minor Ni on the microstructure evolution of a Sn-xNi (x = 0, 0.05 and 0.1 wt.%)/Ni (Poly-crystal/Single-crystal abbreviated as…

476

Abstract

Purpose

The purpose of this article is the effect of doping minor Ni on the microstructure evolution of a Sn-xNi (x = 0, 0.05 and 0.1 wt.%)/Ni (Poly-crystal/Single-crystal abbreviated as PC Ni/SC Ni) solder joint during reflow and aging treatment. Results showed that the intermetallic compounds (IMCs) of the interfacial layer of Sn-xNi/PC Ni joints were Ni3Sn4 phase, while the IMCs of Sn-xNi/SC Ni joints were NiSn4 phase. After the reflow process and thermal aging of different joints, the growth behavior of interfacial layer was different due to the different mechanism of element diffusion of the two substrates. The PC Ni substrate mainly provided Ni atoms through grain boundary diffusion. The Ni3Sn4 phase of the Sn0.05Ni/PC Ni joint was finer, and the diffusion flux of Sn and Ni elements increased, so the Ni3Sn4 layer of this joint was the thickest. The SC Ni substrate mainly provided Ni atoms through the lattice diffusion. The Sn0.1Ni/SC Ni joint increases the number of Ni atoms at the interface due to the doping of 0.1Ni (wt.%) elements, so the joint had the thickest NiSn4 layer.

Design/methodology/approach

The effects of doping minor Ni on the microstructure evolution of an Sn-xNi (x = 0, 0.05 and 0.1 Wt.%)/Ni (Poly-crystal/Single-crystal abbreviated as PC Ni/SC Ni) solder joint during reflow and aging treatment was investigated in this study.

Findings

Results showed that the intermetallic compounds (IMCs) of the interfacial layer of Sn-xNi/PC Ni joints were Ni3Sn4 phase, while the IMCs of Sn-xNi/SC Ni joints were NiSn4 phase. After the reflow process and thermal aging of different joints, the growth behavior of the interfacial layer was different due to the different mechanisms of element diffusion of the two substrates.

Originality/value

In this study, the effect of doping Ni on the growth and formation mechanism of IMCs of the Sn-xNi/Ni (single-crystal) solder joints (x = 0, 0.05 and 0.1 Wt.%) was investigated.

Details

Soldering & Surface Mount Technology, vol. 34 no. 2
Type: Research Article
ISSN: 0954-0911

Keywords

1 – 10 of 74
Per page
102050