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Article
Publication date: 7 October 2019

Shutian Liu, Xueshan Ding and Zeqi Tong

This paper aims to study the energy absorption properties of the thin-walled square tube with lateral piecewise variable thickness under axial crashing and the influence…

Abstract

Purpose

This paper aims to study the energy absorption properties of the thin-walled square tube with lateral piecewise variable thickness under axial crashing and the influence of the tube parameters on energy absorption.

Design/methodology/approach

In this work, the energy absorption properties of the thin-walled square tube were analyzed by theoretical, numerical and experimental approach. The numerical results are obtained based on the finite element method. The explicit formulation for predicting the mean crushing force of the tube with lateral piecewise variable thickness was derived based on Super Folding Element method. The limitation of the prediction formulation was analyzed by numerical calculation. The numerical calculation was also used to compare the energy absorption between the tube with lateral piecewise variable thickness and other tubes, and to carry out the parametric analysis.

Findings

Results indicate that the thin-walled tube with lateral piecewise variable thickness has higher energy absorption properties than the uniform thickness tubes and the tubes with lateral linear variable thickness. The thickness of the corner is the key factor for the energy absorption of the tubes. The thickness of the non-corner region is the secondary factor. Increasing the corner thickness and decreasing the non-corner thickness can make the energy absorption improved. It is also found that the prediction formulation of the mean crushing force given in this paper can quickly and accurately predict the energy absorption of the square tube.

Originality/value

The outcome of the present research provides a design idea to improve the energy absorption of thin-walled tube by designing cross-section thickness and gives an explicit formulation for predicting the mean crushing force quickly and accurately.

Details

Engineering Computations, vol. 36 no. 8
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 10 October 2008

Xia Liu, Mengqiao He, Fang Gao and Peihong Xie

The purpose of this study is to identify factors that may influence Chinese customers' online shopping satisfaction, including those which are ignored by prior studies…

Abstract

Purpose

The purpose of this study is to identify factors that may influence Chinese customers' online shopping satisfaction, including those which are ignored by prior studies, from the perspective of total online shopping experience.

Design/methodology/approach

In this paper, the authors propose a model of the satisfaction process in the e‐commerce environment, identifying key constructs proposed by prior studies and developing hypotheses about which dimensions of online retailer constructs are significant predictors of online shopper satisfaction. The authors test the hypotheses through multiple regression analysis based on a survey of 1,001 online customers.

Findings

The analysis suggests that eight constructs – information quality, web site design, merchandise attributes, transaction capability, security/privacy, payment, delivery, and customer service – are strongly predictive of online shopping customer satisfaction, while the effect of response time is not significant.

Research limitations/implications

This study does not control the differences across product categories; the use of self‐reported scales to measure both independent and dependent variables may imply the possibility of a common method bias for the results.

Originality/value

This research contributes to the study of online shopping customer satisfaction by: developing a model of the satisfaction process in the e‐commerce environment, and identifying factors that may influence Chinese customers' online shopping satisfaction including those which are ignored by prior studies.

Details

International Journal of Retail & Distribution Management, vol. 36 no. 11
Type: Research Article
ISSN: 0959-0552

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Article
Publication date: 18 May 2015

Zhihong Gao and Susan O’Sullivan-Gavin

Given the unique cultural-political context of China, this paper aims to investigate two research questions: What has been the development trajectory of policy-making on…

Abstract

Purpose

Given the unique cultural-political context of China, this paper aims to investigate two research questions: What has been the development trajectory of policy-making on consumer privacy protection in China, and what factors have shaped its development over the years?

Design/methodology/approach

This paper adopts a historical approach and examines the development of Chinese consumer privacy policy during four periods: 1980s, 1990s, 2000s and 2010-present.

Findings

Chinese policy-making on consumer privacy protection has made steady advancement in the past few decades due to factors such as technological development, elite advocacy and emulation of other markets; however, the effects of these factors are conditioned by local forces.

Originality/value

To date, most studies of consumer privacy issues have focused on Western countries, especially the European Union and the USA. A better understanding of how consumer privacy policy has developed in China provides important lessons on the promotion of consumer privacy protection in other developing countries.

Details

Journal of Historical Research in Marketing, vol. 7 no. 2
Type: Research Article
ISSN: 1755-750X

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Book part
Publication date: 25 January 2021

Man-Yee Kan, Guangye He and Xiaogang Wu

Past studies on housework and marital studies seldom considered the possible endogeneity between these two factors. This chapter analyses data of the Women’s Status Survey

Abstract

Past studies on housework and marital studies seldom considered the possible endogeneity between these two factors. This chapter analyses data of the Women’s Status Survey 2010 to investigate the association between satisfaction with family status and housework participation in dual-earner married couples in China. The authors examine the association by ordinary least squares (OLS) regression models and structural equation models (SEM), taking into account of time constraints, economic resources and other demographic characteristics. Results suggest that both men and women are less satisfied with their family status if they share more housework than their partners, after controlling for household income, relative economic contribution, educational qualifications and other factors. Moreover, relative housework contribution is associated more consistently and significantly with satisfaction with family status than absolute housework time. In SEM, the authors include a correlated error term between housework time and satisfaction in the models to take endogeneity between these factors into account. For both urban men and women, relative contribution of housework, but not absolute time of housework, is still negatively associated with family status satisfaction.

Details

Chinese Families: Tradition, Modernisation, and Change
Type: Book
ISBN: 978-1-80071-157-0

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Article
Publication date: 5 October 2015

Zheng Jiang, Haobo Qiu, Ming Zhao, Shizhan Zhang and Liang Gao

In multidisciplinary design optimization (MDO), if the relationships between design variables and some output parameters, which are important performance constraints, are…

Abstract

Purpose

In multidisciplinary design optimization (MDO), if the relationships between design variables and some output parameters, which are important performance constraints, are complex implicit problems, plenty of time should be spent on computationally expensive simulations to identify whether the implicit constraints are satisfied with the given design variables during the optimization iteration process. The purpose of this paper is to propose an ensemble of surrogates-based analytical target cascading (ESATC) method to tackle such MDO engineering design problems with reduced computational cost and high optimization accuracy.

Design/methodology/approach

Different surrogate models are constructed based on the sample point sets obtained by Latin hypercube sampling (LHS) method. Then, according to the error metric of each surrogate model, the repeated ensemble of surrogates is constructed to approximate the implicit objective functions and constraints. Under the framework of analytical target cascading (ATC), the MDO problem is decomposed into several optimization subproblems and the function of analysis module of each subproblem is simulated by repeated ensemble of surrogates, working together to find the optimum solution.

Findings

The proposed method shows better modeling accuracy and robustness than other individual surrogate model-based ATC method. A numerical benchmark problem and an industrial case study of the structural design of a super heavy vertical lathe machine tool are utilized to demonstrate the accuracy and efficiency of the proposed method.

Originality/value

This paper integrates a repeated ensemble method with ATC strategy to construct the ESATC framework which is an effective method to solve MDO problems with implicit constraints and black-box objectives.

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Book part
Publication date: 15 November 2018

Yi-Ming Wei and Hua Liao

Abstract

Details

Energy Economics
Type: Book
ISBN: 978-1-78756-780-1

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Article
Publication date: 6 July 2015

Hyeong-Uk Park, Jae-Woo Lee, Joon Chung and Kamran Behdinan

The purpose of this paper is to study the consideration of uncertainty from analysis modules for aircraft conceptual design by implementing uncertainty-based design…

Abstract

Purpose

The purpose of this paper is to study the consideration of uncertainty from analysis modules for aircraft conceptual design by implementing uncertainty-based design optimization methods. Reliability-Based Design Optimization (RBDO), Possibility-Based Design Optimization (PBDO) and Robust Design Optimization (RDO) methods were developed to handle uncertainties of design optimization. The RBDO method is found suitable for uncertain parameters when sufficient information is available. On the other hand, the PBDO method is proposed when uncertain parameters have insufficient information. The RDO method can apply to both cases. The RBDO, PBDO and RDO methods were considered with the Multidisciplinary Design Optimization (MDO) method to generate conservative design results when low fidelity analysis tools are used.

Design/methodology/approach

Methods combining MDO with RBDO, PBDO and RDO were developed and have been applied to a numerical analysis and an aircraft conceptual design. This research evaluates and compares the characteristics of each method in both cases.

Findings

The RBDO result can be improved when the amount of data concerning uncertain parameters is increased. Conversely, increasing information regarding uncertain parameters does not improve the PBDO result. The PBDO provides a conservative result when less information about uncertain parameters is available.

Research limitations/implications

The formulation of RDO is more complex than other methods. If the uncertainty information is increased in aircraft conceptual design case, the accuracy of RBDO will be enhanced.

Practical implications

This research increases the probability of a feasible design when it considers the uncertainty. This result gives more practical optimization results on a conceptual design level for fabrication.

Originality/value

It is RBDO, PBDO and RDO methods combined with MDO that satisfy the target probability when the uncertainties of low fidelity analysis models are considered.

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Article
Publication date: 10 November 2020

Xiujuan Chen, Zhiqiang Zhang and Jinjing Guo

The purpose of this paper is to provide theoretical basis and data support for researchers to choose appropriate international partners, provide a basis for Chinese…

Abstract

Purpose

The purpose of this paper is to provide theoretical basis and data support for researchers to choose appropriate international partners, provide a basis for Chinese research funding agencies, such as National Natural Science Foundation of China (NSFC) to formulate international research collaboration (IRC) strategies and policies and provide recommendations for the improvement of the internationalization level of China's basic scientific research.

Design/methodology/approach

Based on existing research, this study took output of “Major International (Regional) Joint Research Project” (MIJRP) funded by NSFC and participated by Chinese scholars in the meantime as the analysis object, proposed hypotheses and constructed the indicators of IRC and research output (RO). In addition, the mathematical statistics was used to compare the RO of China's IRC and nonIRC, and the statistical analysis model was used to measure the influence on RO of collaboration country's research capacity, research collaboration between China and US, scope of international research collaboration and reprint author country.

Findings

The RO of China's IRC is higher than that of nonIRC; research capacity of collaboration country has no inevitable effect on the RO of China's IRC; the RO of China's IRC participated by Americans is higher than that without American scholars; expanding the scope of China's IRC to some degree can increase RO; the RO of China's IRC led by foreigners is higher than that led by Chinese. In particular, China–US IRC and foreign scholars acting as the reprint author are two major factors for the RO of China's IRC.

Originality/value

Most of the traditional research on IRC are based on the co-author papers, and this study tried to analyze the characteristics and regularities on IRC from a new view of international collaboration projects, which can be a supplement to the traditional international collaboration research on co-author papers.

Details

Library Hi Tech, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0737-8831

Keywords

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Article
Publication date: 28 February 2020

Jinglong Liu, Zhonghua Wu, Xiaowen Xing and Qizhi He

The purpose of this paper is to find an omnidirectional robust gust response stabilization (GRS) scheme with anti-disturbance and state-limited features.

Abstract

Purpose

The purpose of this paper is to find an omnidirectional robust gust response stabilization (GRS) scheme with anti-disturbance and state-limited features.

Design/methodology/approach

Disturbance observer and barrier Lyapunov techniques, which can, respectively, estimate the lumped disturbances of the dynamic system in real-time and ensure the middle states within some prescribed ranges according to some flight safety indexes.

Findings

In the existing literature, almost all of the GRS controllers are either only for the longitudinal dynamics or only for the latitudinal dynamics. Few studies have considered the gust response alleviation problem with omnidirectional wind disturbance and full aircraft model.

Originality/value

This paper proposes a fresh scheme to deal with a more holistic GRS problem; the disturbance observer based (DOB) barrier Lyapunov backstepping longitudinal controller has been put forward; DOB nonlinear dynamic inversion to handle the multi-input-multi-output lateral dynamics; and to closely connect the two loops of the latitudinal dynamics, a manipulating variable conversion method is proposed.

Details

Aircraft Engineering and Aerospace Technology, vol. 92 no. 6
Type: Research Article
ISSN: 1748-8842

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Article
Publication date: 31 December 2006

Tassos Dimitriou and Ioannis Krontiris

Nodes in sensor networks do not have enough topology information to make efficient routing decisions. To relay messages through intermediate sensors, geographic routing…

Abstract

Nodes in sensor networks do not have enough topology information to make efficient routing decisions. To relay messages through intermediate sensors, geographic routing has been proposed as such a solution. Its greedy nature, however, makes routing inefficient especially in the presence of topology voids or holes. In this paper we present GRAViTy (Geographic Routing Around Voids In any TopologY of sensor networks), a simple greedy forwarding algorithm that combines compass routing along with a mechanism that allows packets to explore the area around voids and bypass them without significant communication overhead. Using extended simulation results we show that our mechanism outperforms the right‐hand rule for bypassing voids and that the resulting paths found well approximate the corresponding shortest paths. GRAViTy uses a cross‐layered approach to improve routing paths for subsequent packets based on experience gained by former routing decisions. Furthermore, our protocol responds to topology changes, i.e. failure of nodes, and efficiently adjusts routing paths towards the destination.

Details

International Journal of Pervasive Computing and Communications, vol. 2 no. 4
Type: Research Article
ISSN: 1742-7371

Keywords

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