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Article
Publication date: 6 March 2024

Qiuchen Zhao, Xue Li, Junchao Hu, Yuehui Jiang, Kun Yang and Qingyuan Wang

The purpose of this paper is to determine the ultra-high cycle fatigue behavior and ultra-slow crack propagation behavior of selective laser melting (SLM) AlSi7Mg alloy under…

143

Abstract

Purpose

The purpose of this paper is to determine the ultra-high cycle fatigue behavior and ultra-slow crack propagation behavior of selective laser melting (SLM) AlSi7Mg alloy under as-built conditions.

Design/methodology/approach

Constant amplitude and two-step variable amplitude fatigue tests were carried out using ultrasonic fatigue equipment. The fracture surface of the failure specimen was quantitatively analyzed by scanning electron microscope (SEM).

Findings

The results show that the competition of surface and interior crack initiation modes leads to a duplex S–N curve. Both manufacturing defects (such as the lack of fusion) and inclusions can act as initially fatal fatigue microcracks, and the fatigue sensitivity level decreases with the location, size and type of the maximum defects.

Originality/value

The research results play a certain role in understanding the ultra-high cycle fatigue behavior of additive manufacturing aluminum alloys. It can provide reference for improving the process parameters of SLM technology.

Details

International Journal of Structural Integrity, vol. 15 no. 2
Type: Research Article
ISSN: 1757-9864

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Article
Publication date: 10 September 2024

Xuying Li, Yanbin Liu, Jie Huang, Deyu Sang, Kun Yang and Jinbo Ling

This paper aims to reveal the influence of the grooved texture parameters on the lubrication performance of circular pocket-roller pairs in cylindrical roller bearings.

34

Abstract

Purpose

This paper aims to reveal the influence of the grooved texture parameters on the lubrication performance of circular pocket-roller pairs in cylindrical roller bearings.

Design/methodology/approach

In this paper, the thermal elastohydrodynamic lubrication mathematical model of the grooved texture circular pocket-roller pair was established, the finite difference method and successive over-relaxation method were used to solve the model, the influence of texture quantity, texture depth and texture area ratio on circumferential bearing capacity, friction coefficient, maximum temperature rise, stiffness and damping of the circular pocket-roller pairs were analyzed.

Findings

The results show that texture quantity, texture depth and texture area ratio significantly influence the static and dynamic characteristics of circular pocket-roller pairs. The suitable surface groove texture parameters can dramatically improve the circumferential bearing capacity, reduce the friction coefficient, inhibit the maximum temperature rise and increase the stiffness and damping of the circular pocket-roller pairs.

Originality/value

The research in this paper can provide a theoretical basis for the optimization design of pockets in cylindrical roller bearings to reduce friction and vibration.

Details

Industrial Lubrication and Tribology, vol. 76 no. 9
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 13 August 2019

Hui Lü, Kun Yang, Wen-bin Shangguan, Hui Yin and DJ Yu

The purpose of this paper is to propose a unified optimization design method and apply it to handle the brake squeal instability involving various uncertainties in a unified…

134

Abstract

Purpose

The purpose of this paper is to propose a unified optimization design method and apply it to handle the brake squeal instability involving various uncertainties in a unified framework.

Design/methodology/approach

Fuzzy random variables are taken as equivalent variables of conventional uncertain variables, and a unified response analysis method is first derived based on level-cut technique, Taylor expansion and central difference scheme. Next, a unified reliability analysis method is developed by integrating the unified response analysis and fuzzy possibility theory. Finally, based on the unified reliability analysis method, a unified reliability-based optimization model is established, which is capable of optimizing uncertain responses in a unified way for different uncertainty cases.

Findings

The proposed method is extended to perform squeal instability analysis and optimization involving various uncertainties. Numerical examples under eight uncertainty cases are provided and the results demonstrate the effectiveness of the proposed method.

Originality/value

Most of the existing methods of uncertainty analysis and optimization are merely effective in tackling one uncertainty case. The proposed method is able to handle the uncertain problems involving various types of uncertainties in a unified way.

Details

Engineering Computations, vol. 37 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 2 August 2022

Mingkai Yue, Meie Li, Ning An, Kun Yang, Jian Wang and Jinxiong Zhou

Selective electron beam melting (SEBM) is one of the popular powder-bed additive manufacturing (AM) technologies. The purpose of this paper is to develop a simulation strategy for…

234

Abstract

Purpose

Selective electron beam melting (SEBM) is one of the popular powder-bed additive manufacturing (AM) technologies. The purpose of this paper is to develop a simulation strategy for SEBM process to get data which are vital for realistic failure prediction and process parameters control for real complex components.

Design/methodology/approach

Focusing on the SEBM process of tantalum, this paper presents a three-dimensional thermo-mechanical modeling strategy based on ABAQUS and its subroutines. The simulation strategy used in this paper is developed for SEBM process of pure tantalum but could be extended to other AM fabrication technologies and other metals without difficulties.

Findings

The simulation of multi-track multi-layer SEBM process of tantalum was carried out to predict the temperature field, the molten pool evolution and the residual stress distribution. The key information such as inter-track molten pool overlapping ratio and inter-layer refusion state can be extracted from the obtained molten pool morphologies, which are vital for realistic failure prediction and process parameters control for real components. The authors finally demonstrate the capability of the strategy used by simulating a 2 mm × 2 mm × 10 mm lattice structure with total 200 layers.

Originality/value

The simulation of multi-track multi-layer SEBM process of tantalum was carried out. The key information such as inter-track molten pool overlapping ratio and inter-layer refusion state can be extracted. The authors finally demonstrate the capability of the strategy used by simulating a lattice structure. Not only temperature distribution but also stress evolution are captured. Our simulation strategy is developed for the SEBM process of pure tantalum, but it could be extended to other AM fabrication technologies and other metals without difficulties.

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Article
Publication date: 19 December 2024

Rimi Zakaria and Kun Michelle Yang

This study extends the relationship, behavior and condition perspective on international business negotiation to predict cross-border merger and acquisition negotiation outcomes…

16

Abstract

Purpose

This study extends the relationship, behavior and condition perspective on international business negotiation to predict cross-border merger and acquisition negotiation outcomes. Taking a two-dimensional approach to classifying institutional distance (ID), the authors identify a set of cognitive and behavioral mechanisms underlying interfirm negotiation processes. The purpose of this study is to propose that the degree, interaction, pluralistic discord of institutional dimensions and the relative importance of IDs shape cross-national negotiation workflows and tactics.

Design/methodology/approach

Using a cross-sectional sample of over 76,000 interfirm merger and acquisition deals, the authors find that this study’s empirical results support their overarching theory of relationship-, behavior- and condition-focused cross-border negotiation outcomes. Applying the Mahalanobis approach to multidimensional IDs, the authors conduct logistic regression analyses to run the competing models to test the hypotheses.

Findings

This research finds that the degree of dimensional interactions, pluralistic discord and relative impact – all three ID dynamics – at the dyadic level undermine the likelihood of deal completion. As such, interfirm negotiations require managing cognitive and behavioral costs underlying the intricacies of IDs.

Originality/value

The relationship, behavior and condition-centric interfirm negotiation theory proposed in this study informs our existing knowledge of both institutional and behavioral negotiations. Simulating the context of de facto deals, the research model simultaneously captures formal and informal ID dimensions as a tandem to identify some exogenous and endogenous bargaining dynamics to provide new insights. The results of this study demonstrate that the codified, authoritative, and legally enforceable attributes of distance (i.e. formal directives) undermine cross-border deals more acutely than the socio-culturally embedded norms (i.e. informal conventions).

Details

Review of International Business and Strategy, vol. 35 no. 1
Type: Research Article
ISSN: 2059-6014

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Article
Publication date: 24 January 2018

Kun (Michelle) Yang and Michael J. Pisani

This study aims to explore “what impact does competition from informal enterprises have on formal firms” within the Chinese economic and business environment.

406

Abstract

Purpose

This study aims to explore “what impact does competition from informal enterprises have on formal firms” within the Chinese economic and business environment.

Design/methodology/approach

The paper opted for an exploratory study utilizing the cross-sectional survey data “2012 China Enterprise Survey” conducted by the World Bank. The survey is composed of approximately 200 business-related questions across the spectrum of business operations. In all, 2,700 privately owned Chinese firms are included in the logistic regression analysis.

Findings

Results show the impact of informal firm competition upon formal firms in China are influenced by geographical location, industry sector, ownership profile, governmental ownership, online presence and the extent of obeying labor regulations or the time spent in handling the governmental regulatory environment. There is a competitive and complementary simultaneous intertwined relationship between formal and informal economy. It occurs in a formal economy not fully divorced from the structural inertia of the planned economy as it transitions to a market-based economy.

Practical implications

This paper extended the assumption of institutional theory and presented it as a dynamic view of the evolution of organizations. It contributes by offering a simultaneous dual relationship between the formal and informal economy. It also adds one more potential feature of populations in the population ecology theory.

Originality/value

This exploratory paper empirically examines the impacts of informal sector enterprises on formal sectors firms in China and proposes a dual force effect of the informal economy to the formal economy given the current Chinese institutional environment. The study also provides a platform for further research on the interactions between the formal and informal sectors in emerging markets.

Details

Chinese Management Studies, vol. 12 no. 1
Type: Research Article
ISSN: 1750-614X

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Article
Publication date: 22 February 2024

Zhaoyang Sun, Haiyang Zhou, Tianchen Yang, Kun Wang and Yubo Hou

The shape of a product plays a crucial role in shaping consumer behavior. Despite the voluminous research on factors influencing consumers’ shape preferences, there remains a…

557

Abstract

Purpose

The shape of a product plays a crucial role in shaping consumer behavior. Despite the voluminous research on factors influencing consumers’ shape preferences, there remains a limited understanding of how the busy mindset, a mentality increasingly emphasized by marketing campaigns, works. This study aims to fill this gap by exploring the relationship between a busy mindset and the preference for angular-shaped versus circular-shaped products and brand logos.

Design/methodology/approach

This research consists of seven experimental studies using various shape stimuli, distinct manipulations of busy mindset, different assessments of shape preference and samples drawn from multiple countries.

Findings

The findings reveal that a busy mindset leads to a preference for angular shapes over circular ones by amplifying the need for uniqueness. In addition, these effects are attenuated when products are scarce.

Originality/value

This research represents one of the pioneering efforts to study the role of a busy mindset on consumers’ aesthetic preferences. Beyond yielding insights for practitioners into visual marketing, this research contributes to the theories on the busy mindset and shape preference.

Details

Journal of Product & Brand Management, vol. 33 no. 3
Type: Research Article
ISSN: 1061-0421

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Article
Publication date: 3 November 2014

Kun Ma and Bo Yang

This paper aims to study a bibliography acquisition approach to verify the bibliography by author name from the integrated system and the metadata from the digital object…

447

Abstract

Purpose

This paper aims to study a bibliography acquisition approach to verify the bibliography by author name from the integrated system and the metadata from the digital object identifier (DOI) content negotiation proxy. As managed scientific research papers increase at a higher rate, an accurate and automated scheme for bibliography acquisition is desirable.

Design/methodology/approach

This study develops a framework using DOI content negotiation proxy as context for the entering of the bibliography. The bibliography acquisition architecture is composed of three point of views to reduce the complexity: terminal UI, service deployed in the cloud and DOI content negotiation proxy. To simplify the service interface and support many kinds of bibliographic formats, this paper presents the independent BibModel and its template-based model transformation engine to support rich bibliographic records.

Findings

An important finding of this article is that we do some significant development work to combine the open CrossCite DOI content service and DOI resolvers of registry agencies. As more than 95 per cent of DOIs are owned or managed by CrossRef, DataCite, ISTIC and mEDTA DOI registry agencies, it is a common universal approach for the scientific research paper results with DOIs.

Practical implications

Through a simple method built quickly from freely available parts, it is partially successful, suggesting the scheme can be integrated with third-party systems, such as the management system of scientific research results and the electronic journal management system. The analysis of the application’s effect shows the ability to verify the authenticity of the paper by author name from the system and the metadata from our DOI content negotiation proxy.

Originality/value

This paper proposes an original and simple framework to acquire the metadata of bibliographies automatically. No detailed evaluative study has been carried out supporting both DOI content negotiation and resolver. This work shows how to implement the acquisition approach and how to integrate this framework with the current system.

Details

The Electronic Library, vol. 32 no. 6
Type: Research Article
ISSN: 0264-0473

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Article
Publication date: 3 May 2016

Kun Yang, Xingwang You, Jiabing Wang and Kambiz Vafai

The purpose of this paper is to analyze two different approaches (Models A and B) for an adiabatic boundary condition at the wall of a channel filled with a porous medium. The…

262

Abstract

Purpose

The purpose of this paper is to analyze two different approaches (Models A and B) for an adiabatic boundary condition at the wall of a channel filled with a porous medium. The analytical solutions for the velocity distribution, the fluid and solid phase temperature distributions are derived and compared with numerical solutions. The phenomenon of heat flux bifurcation for Model A is demonstrated. The effects of pertinent parameter C on the applicability of the Models A and B are discussed. Analytical solutions for the overall Nusselt number and the heat flux distribution at the channel wall are derived and the influence of pertinent parameters Da and k on the overall Nusselt number and the heat flux distribution is discussed.

Design/methodology/approach

Two approaches (Models A and B) for an adiabatic boundary condition in porous media under local thermal non-equilibrium (LTNE) conditions are analyzed in this work. The analysis is applied to a microchannel which is modeled as a porous medium.

Findings

The phenomenon of heat flux bifurcation at the wall for Model A is demonstrated. The effect of pertinent parameter C on the applicability of each model is discussed. Model A is applicable when C is relatively large and Model B is applicable when C is small. The heat flux distribution is obtained and the influence of Da and k is discussed. For Model A, ϕAfin increases and ϕAsub, ϕAcover decrease as Da decreases and k is held constant, ϕAsub increases and ϕAfin, ϕAcover decrease as k increases while Da is held constant; for Model B, ϕBfin increases and ϕBsub decreases either as Da decreases or k decreases. The overall Nusselt number is also obtained and the effect of Da and k is discussed: Nu increases as either Da or k decrease for both models. The overall Nusselt number for Model A is larger than that for Model B when Da is large, the overall Nusselt numbers for Models A and B are equivalent when Da is small.

Research limitations/implications

Proper representation of the energy equation and the boundary conditions for heat transfer in porous media is very important. There are two different models for representing energy transfer in porous media: local thermal equilibrium (LTE) and LTNE. Although LTE model is more convenient to use, the LTE assumption is not valid when a substantial temperature difference exists between the solid and fluid phases.

Practical implications

Fluid flow and convective heat transfer in porous media have many important applications such as thermal energy storage, nuclear waste repository, electronic cooling, geothermal energy extraction, petroleum processing and heat transfer enhancement.

Social implications

This work has important fundamental implications.

Originality/value

In this work the microchannel is modeled as an equivalent porous medium. The analytical solutions for the velocity distribution, the fluid and solid phase temperature distributions are obtained and compared with numerical solutions. The first type of heat flux bifurcation phenomenon, which indicates that the direction of the temperature gradient for the fluid and solid phases is different at the channel wall, occurs when Model A is utilized. The effect of pertinent parameter C on the applicability of the models is also discussed. The analytical solutions for the overall Nusselt number and the heat flux distribution at the channel wall are derived, and the effects of pertinent parameters Da and k on the overall Nusselt number and the heat flux distribution are discussed.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 26 no. 3/4
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 26 June 2009

Ming‐Chih Yew, Mars Tsai, Dyi‐Chung Hu, Wen‐Kun Yang and Kuo‐Ning Chiang

The wafer level package (WLP) is a cost‐effective solution for electronic packaging and has been increasingly applied in recent years. The purpose of this paper is to propose a…

822

Abstract

Purpose

The wafer level package (WLP) is a cost‐effective solution for electronic packaging and has been increasingly applied in recent years. The purpose of this paper is to propose a newly developed packaging technology, based on the concepts of the WLP, the panel base package (PBP) technology, in order to further obtain the capability of signal fan‐out for fine‐pitched integrated circuits (ICc).

Design/methodology/approach

In the PBP, the filler material is selected to fill the trench around the chip and provide a smooth surface for the redistribution lines. Therefore, the solder bumps could be located on both the filler and the chip surface and the pitch of the chip side is fanned‐out. The design concept and the manufacturing process of the PBP would first be described in this study. The three‐dimensional finite element model is established based on the real testing sample and the thermo‐mechanical behavior of the PBP is simulated.

Findings

It is found that the solder joint reliability of the PBP can be highly improved because of the applied stress buffer layer. However, the accumulated stress/strain from the coefficient of thermal expansion mismatch may transfer to the metal lines in package. In order to enhance the robustness of the redistribution lines, the bypassed type interconnect is suggested. Moreover, the trace/pad connecting junction and the conductive via which have smooth outline are preferred to avoid stress concentration effects.

Originality/value

In this paper, a low‐cost and short time‐to‐market packaging technology is proposed which is especially suitable for high density IC devices. The PBP technology has the ability to meet the requirements of major reliability testing conditions and it will have a high potential for application in the near future.

Details

Soldering & Surface Mount Technology, vol. 21 no. 3
Type: Research Article
ISSN: 0954-0911

Keywords

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