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Book part
Publication date: 21 November 2014

Yixiao Sun

New asymptotic approximations are established for the Wald and t statistics in the presence of unknown but strong autocorrelation. The asymptotic theory extends the usual…

Abstract

New asymptotic approximations are established for the Wald and t statistics in the presence of unknown but strong autocorrelation. The asymptotic theory extends the usual fixed-smoothing asymptotics under weak dependence to allow for near-unit-root and weak-unit-root processes. As the locality parameter that characterizes the neighborhood of the autoregressive root increases from zero to infinity, the new fixed-smoothing asymptotic distribution changes smoothly from the unit-root fixed-smoothing asymptotics to the usual fixed-smoothing asymptotics under weak dependence. Simulations show that the new approximation is more accurate than the usual fixed-smoothing approximation.

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Article
Publication date: 3 September 2019

Jufeng Wang and Fengxin Sun

This paper aims to present an interpolating element-free Galerkin (IEFG) method for the numerical study of the time-fractional diffusion equation, and then discuss the…

Abstract

Purpose

This paper aims to present an interpolating element-free Galerkin (IEFG) method for the numerical study of the time-fractional diffusion equation, and then discuss the stability and convergence of the numerical solutions.

Design/methodology/approach

In the time-fractional diffusion equation, the time fractional derivatives are approximated by L1 method, and the shape functions are constructed by the interpolating moving least-squares (IMLS) method. The final system equations are obtained by using the Galerkin weak form. Because the shape functions have the interpolating property, the unknowns can be solved by the iterative method after imposing the essential boundary condition directly.

Findings

Both theoretical and numerical results show that the IEFG method for the time-fractional diffusion equation has high accuracy. The stability of the fully discrete scheme of the method on the time step is stable unconditionally with a high convergence rate.

Originality/value

This work will provide an interpolating meshless method to study the numerical solutions of the time-fractional diffusion equation using the IEFG method.

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Article
Publication date: 1 March 2001

Dean Tjosvold and Haifa F. Sun

Maintaining relationships may be difficult in conflict because strong influence attempts can communicate disrespect, especially among Chinese people. The theory of…

Abstract

Maintaining relationships may be difficult in conflict because strong influence attempts can communicate disrespect, especially among Chinese people. The theory of cooperation and competition was used to investigate the effects of persuasion and control influence attempts and social context in conflict. Results from an experimental study support the reasoning that persuasion communicates respect and develops a cooperative relationship. In contrast, coercion communicates disrespect, develops competitive relationships, and results in rejection of the opposing view and negotiator. Consistent with North American research, cooperative compared to competitive context was found to lead to more openness toward the opposing position and negotiator. These results were interpreted as suggesting that persuasion, communication of respect, and a cooperative context facilitate productive conflict management between Chinese people.

Details

International Journal of Conflict Management, vol. 12 no. 3
Type: Research Article
ISSN: 1044-4068

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Article
Publication date: 13 May 2019

Mengjiao Guo, F. Sun and Zuozhu Yin

This paper used a novel technique, which is thermo-compression bonding, and Sn-1.0Ag-0.5Cu solder to form a full intermetallic compound (IMC) Cu3Sn joints (Cu/Cu3Sn/Cu…

Abstract

Purpose

This paper used a novel technique, which is thermo-compression bonding, and Sn-1.0Ag-0.5Cu solder to form a full intermetallic compound (IMC) Cu3Sn joints (Cu/Cu3Sn/Cu joints). The purpose of the study is to form high-melting-point IMC joints for high-temperature power electronics applications. The study also investigated the effect of temperature gradient on the microstructure evolution and the growth behavior of IMCs.

Design/methodology/approach

In this paper, the thermo-compression bonding technique was used to form full Cu3Sn joints.

Findings

Experimental results indicated that full Cu/Cu3Sn/Cu solder joints with the thickness of about 5-6 µm are formed in a short time of 9.9 s and under a low pressure of 0.016 MPa at 450°C by thermo-compression bonding technique. During the bonding process, Cu6Sn5 grew with common scallop-like shape at Cu/SAC105 interfaces, which was followed by the growth of Cu3Sn with planar-like shape between Cu/Cu6Sn5 interfaces. Meanwhile, the morphology of Cu3Sn transformed from a planar-like shape to wave-like shape until full IMCs solder joints were eventually formed during thermo-compression bonding process. Asymmetrical growth behavior of the interfacial IMCs was also clearly observed at both ends of the Cu/SAC105 (Sn-1.0Ag-0.5Cu)/Cu solder joints. Detailed reasons for the asymmetrical growth behavior of the interfacial IMCs during thermo-compression bonding process are given. The compound of Ag element causes a reduction in Cu dissolution rate from the IMC into the solder solution at the hot end, inhibiting the growth of IMCs at the cold end.

Originality/value

This study used the thermo-compression bonding technique and Sn-1.0Ag-0.5Cu to form full Cu3Sn joints.

Details

Soldering & Surface Mount Technology, vol. 31 no. 4
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 11 October 2020

Zhu Feng, Shaotao Zhi, Xuecheng Sun, Lili Yan, Cui Liu and Chong Lei

This paper aims to investigate the influence of structure parameters on giant-magnetoimpedance (GMI) effect measured by non-contact method.

Abstract

Purpose

This paper aims to investigate the influence of structure parameters on giant-magnetoimpedance (GMI) effect measured by non-contact method.

Design/methodology/approach

The GMI sensor contains a Co-based internal magnetic core fabricated by laser cutting and an external solenoid. The influences of magnetic permeability of magnetic core and structure parameters on GMI effect were calculated in theoretical model. The output impedance, resistance, reactance and GMI ratio were measured by non-contact method using impedance analyzer.

Findings

Enhancing external magnetic field intensity can decrease the magnetic permeability of core, which has vital influences on the magnetic property and the output response of GMI sensor. In addition, increasing the width of magnetic core and the number of solenoid turns can increase the maximum GMI ratio. The maximum GMI ratio is 3,230% with core width of 6 mm and solenoid turns of 200.

Originality/value

Comparing with traditional contact-measured GMI sensor, the maximum GMI ratio and the magnetic field sensitivity are improved and the power consumption is decreased in non-contact measured GMI sensor. GMI sensor measured by non-contact method has a wide range of potential applications in ultra-sensitive magnetic field detection.

Details

Sensor Review, vol. 40 no. 6
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 3 April 2017

Ren-huai Liu, Kai Sun and Dongchuan Sun

The purpose of this article is to put forward China’s Hanyu Pinyin word guanli as an academic basic term to the world.

Abstract

Purpose

The purpose of this article is to put forward China’s Hanyu Pinyin word guanli as an academic basic term to the world.

Design/methodology/approach

GUANLI as an academic basic term, which holds multiple meanings of several English words, such as management, administration, governance, etc. As a basic term, GUANLI, derived several words, such as GUANLIOLOGY, GUANLIST/GUANLIER and GUANLIWORK/GUANLIJOB, to precisely and exactly convey the Chinese GUANLI ideas. It is the historical mission and opportunity for the authors to research and establish the Chinese School of Modern GUANLI Science (CSMGS).

Findings

It is inevitably necessary to build the combined Chinese–Western discourse system of GUANLI science (CCWDSGS). Some other research results of CSMGS are also presented in this paper.

Research limitations/implications

It is needless to say that there are still lots of problems in China, including in the GUANLI field. These problems will gradually be solved in China’s reform and development that takes place continuously. New problems will come up while old problems are being solved and settled; problems producing in a loop, problems solving in a loop, this is the dialectics. The authors have full confidence in solving problems, as well as in China’s development and future.

Originality/value

Practice comes first and then it is followed by theory. The authors first have the “China Model”, followed by the “Chinese School” consequently. The “China Model” has already been there, and the “Chinese School” relies on the author’s proactive research and innovation. It is just the right time for the authors to study and create the CSMGS. This is the historical mission and opportunity awaited by contemporary Chinese.

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Article
Publication date: 14 May 2021

F Sun, Zhen Pan, Yang Liu, Xiang Li, Haoyu Liu and Wenpeng Li

The purpose of this paper is to quickly manufacture full Cu3Sn-microporous copper composite joints for high-temperature power electronics applications and study the…

Abstract

Purpose

The purpose of this paper is to quickly manufacture full Cu3Sn-microporous copper composite joints for high-temperature power electronics applications and study the microstructure evolution and the shear strength of Cu3Sn at different bonding times.

Design/methodology/approach

In this paper, a novel structure of Cu/composite solder sheet/Cu was designed. The composite solder sheet was made of microporous copper filled with Sn. The composite joint was bonded by thermo-compression bonding under pressure of 0.6 MPa at 300°C. The microstructure evolution and the growth behavior of Cu3Sn at different bonding times were observed by electron microscope and metallographic microscope. The shear strength of the joint was measured by shear machine.

Findings

At initial bonding stage the copper atoms in the substrate and the copper atoms in the microporous copper dissolved into the liquid Sn. Then the scallop-liked Cu6Sn5 phases formed at the interface of liquid Sn/microporous copper and liquid Sn/Cu substrates. During the liquid Sn changing to Cu6Sn5 phases, Cu3Sn phases formed and grew at the interface of Cu6Sn5/Cu substrates and Cu6Sn5/microporous copper. After that the Cu3Sn phases continued to grow and the Cu3Sn-microporous copper composite joint with a thickness of 100 µm was successfully obtained. The growth rule of Cu3Sn was parabolic growth. The shear strength of the composite joints was about 155 MPa.

Originality/value

This paper presents a novel full Cu3Sn-microporous copper composite joint with high shear strength for high-temperature applications based on transient liquid phase bonding. The microstructure evolution and the growth behavior of Cu3Sn in the composite joints were studied. The shear strength and the fracture mechanism of the composite joints were studied.

Details

Soldering & Surface Mount Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0954-0911

Keywords

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Article
Publication date: 1 January 1994

Marcia Henry, Linda Keenan and Michael Reagan

The following Melvyl system search sheet updates the 1991 search sheet published in the first edition of Search Sheets for OPACs on the Internet. Although the first…

Abstract

The following Melvyl system search sheet updates the 1991 search sheet published in the first edition of Search Sheets for OPACs on the Internet. Although the first edition's search sheet is still very useable, it does not document some new features (e.g., Save Set, the Mail To, and Update commands) as well as the change in I.P. address. The Melvyl search sheet is the first of several revised search sheets to be published in CWIS. For example, there have been changes in the Harvard, Rensselaer, University of Illinois, and CARL search sheets to name just a few. The next edition of Search Sheets for OPACs on the Internet will have search sheets for over one hundred new OPACs not covered in the first edition. We hope to keep up with the changes in the OPACs of both editions in CWIS.

Details

Campus-Wide Information Systems, vol. 11 no. 1
Type: Research Article
ISSN: 1065-0741

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Article
Publication date: 1 March 1994

A. Seyam and F. Sun

Applies a sound theory to predict in‐plane bending deformation of flexible beams under large overall motions to predict the locus of the trailing end of the ply during…

Abstract

Applies a sound theory to predict in‐plane bending deformation of flexible beams under large overall motions to predict the locus of the trailing end of the ply during wiping off the conveyor surface of the layup machine. A computerized numerical solution was used to estimate the locus of the trailing end of the ply for seven woven fabrics of wide range of thickness, weight, and bending rigidity. The least square method was employed to obtain regression relationship between the horizontal and vertical displacement of the trailing end of the ply for each of the seven fabrics. The regression equations and the slat height were used to calculate the minimum gap between two slats of the stacking conveyor so that the fabric trailing end does not touch the top or the side surfaces of a slat during the layup process.

Details

International Journal of Clothing Science and Technology, vol. 6 no. 1
Type: Research Article
ISSN: 0955-6222

Keywords

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Book part
Publication date: 11 August 2014

Abstract

Details

Multidisciplinary Insights from New AIB Fellows
Type: Book
ISBN: 978-1-78441-038-4

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