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Article
Publication date: 14 October 2013

Gang Zhang, Jianhua Wu, Pinkuan Liu and Han Ding

Based on the inverse kinematics and task space dynamic model, this paper aims to design a high-precision trajectory tracking controller for a 2-DoF translational parallel…

Abstract

Purpose

Based on the inverse kinematics and task space dynamic model, this paper aims to design a high-precision trajectory tracking controller for a 2-DoF translational parallel manipulator (TPM) driven by linear motors.

Design/methodology/approach

The task space dynamic model of a 2-DoF TPM is derived using Lagrangian equation of the first type. A task space dynamic model-based feedforward controller (MFC) is designed, which is combined with a cascade PID/PI controller and velocity feedforward controller (VFC) to construct a hybrid PID/PI+VFC/MFC controller. The hybrid controller is implemented in MATLAB/dSPACE real-time control platform. Experiment results are given to validate the effectiveness and industrial applicability of the hybrid controller.

Findings

The MFC can compensate for the nonlinear dynamic characteristics of a 2-DoF TPM and achieve better tracking performance than the conventional acceleration feedforward controller (AFC).

Originality/value

The task space dynamic model-based hybrid PID/PI+VFC/MFC controller is proposed for a 2-DoF linear-motor-driven TPM, which reduces the tracking error by at least 15 percent compared with conventional hybrid PID/PI+VFC/AFC controller. This control scheme can be extended to high-speed and high-precision trajectory tracking control of other parallel manipulators by reprogramming the feedforward signals of traditional cascade PID/PI controller.

Details

Industrial Robot: An International Journal, vol. 40 no. 6
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 1 August 2000

Jicun Lu, Jianhua Wu, Yih Pin Liew, Thiam Beng Lim and Xiangfu Zong

The impact of underfill properties on the thermomechanical reliability of flip chip on board (FCOB) assembly is addressed in this paper. FCOB assemblies using three…

Abstract

The impact of underfill properties on the thermomechanical reliability of flip chip on board (FCOB) assembly is addressed in this paper. FCOB assemblies using three underfill encapsulants were subjected to a thermal cycling test. The performance of the underfill encapsulants was assessed by a statistical analysis of the failure distribution of the FCOB assemblies. The failure modes in the thermal cycling test were found to be solder joint cracks, delamination at underfill/chip passivation interface, and underfill internal cracks. An attempt was made to correlate these failures with underfill properties such as the coefficient of thermal expansion (CTE), modulus, glass transition temperature (Tg), and adhesive strength to the chip. Additionally, nonlinear finite element analysis (FEA) was conducted to verify the experimental results.

Details

Soldering & Surface Mount Technology, vol. 12 no. 2
Type: Research Article
ISSN: 0954-0911

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Article
Publication date: 3 August 2010

DongLin Pu, JianHua Wu, ZhenHua Xiong, XinJun Sheng and Han Ding

The purpose of this paper is to explore the nonlinear analysis on the relay feedback technology (RFT) applied to parameters identification of servo mechanism.

Abstract

Purpose

The purpose of this paper is to explore the nonlinear analysis on the relay feedback technology (RFT) applied to parameters identification of servo mechanism.

Design/methodology/approach

In order to investigate nonlinear elements' influence on RFT, the analysis was conducted in the velocity and current control loops, respectively. The RFT algorithm for modeling servo mechanism with friction was developed to overcome the nonlinear influence. Furthermore, the results from experiments were presented to validate the analysis and illustrated the advantages of the proposed method.

Findings

The Coulomb friction and current changing are the main nonlinear influence on the RFT application in servo mechanism. The friction effects should be included to servo system modeling based on RFT.

Practical implications

Some suggestions concluded from nonlinear analysis are useful to optimize the selection of parameters in RFT. And the proposed algorithm is applicable to modeling servo mechanism with friction.

Originality/value

The nonlinear analysis in the different control loops of servo mechanism based on RFT is presented and the effective identification approach is proposed in this paper.

Details

Assembly Automation, vol. 30 no. 3
Type: Research Article
ISSN: 0144-5154

Keywords

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Article
Publication date: 7 November 2019

Peng Dong, Shengdun Zhao, Shuqin Fan, Muzhi Zhu and Peng Zhang

The drive shaft and the distribution shaft of a traditional radial piston pump are in a cantilever state. To solve this problem, this paper aims to present a radial piston…

Abstract

Purpose

The drive shaft and the distribution shaft of a traditional radial piston pump are in a cantilever state. To solve this problem, this paper aims to present a radial piston pump with through shaft driving and valve plate distribution.

Design/methodology/approach

The working principle of the pump is discussed in detail. In this radial piston pump, valve plate distribution parts are designed to distribute oil to the piston chambers, and the distribution shaft is replaced. A bearing is installed between the stator and rotator to reduce the friction. The transmission shaft is supported by two bearings to ensure smooth operation. The support force of the transmission shaft is optimized. In addition, the flow pulsation principle is presented. To accomplish the change, the displacement of the radial piston pump, the proportional control system is designed.

Findings

After completing the machining and assembly of the pump, an experimental study was carried out. The results show that the output flow of the pump is basically the same as the theoretical flow.

Originality/value

The friction between the slipping shoes and the stator is greatly reduced due to the function of rolling bearings. The higher stability of the driveshaft is obtained for the reason of double-sided support. The radial piston pump has a novel structural design in reducing the friction between the shoes and the stator and improving the stability of the transmission shaft.

Details

Assembly Automation, vol. 40 no. 2
Type: Research Article
ISSN: 0144-5154

Keywords

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Article
Publication date: 2 May 2017

Linhai Wu, Qipeng Hu, Jianhua Wang and Dian Zhu

In China, a major grain producer, rice losses during harvest cannot be ignored. The purpose of this paper is to assess the extent of rice harvest losses in major…

Abstract

Purpose

In China, a major grain producer, rice losses during harvest cannot be ignored. The purpose of this paper is to assess the extent of rice harvest losses in major grain-producing areas in China by a sampling survey, and to further analyze the main factors influencing rice harvest losses using an ordered multinomial logistic model.

Design/methodology/approach

In this study, data were collected using a multi-stage sampling method from ten major rice-producing provinces/regions in China. On this basis, five counties were selected from each of these provinces/regions. In the actual survey, house numbers were randomly selected, and then corresponding farmer households were visited by trained investigators.

Findings

The survey found that 56.22 percent of respondents believed that rice harvest losses were 4 percent or lower in China, though there were differences among the provinces. The proportion of family business income, planting scale, mechanization level, timely harvest, and operational meticulousness had negative effects on rice harvest losses. On the other hand, farmers’ experience of employment as migrant workers had a positive effect on rice harvest losses. In addition, bad weather and short handedness during harvest significantly increased rice harvest losses.

Originality/value

The meaning of rice harvest losses was defined based on previous research findings on the definition of grain harvest losses and the realities in China. The current rice harvest losses in different areas in China were analyzed based on sampling survey data from 957 farmers in ten provinces in China.

Details

China Agricultural Economic Review, vol. 9 no. 2
Type: Research Article
ISSN: 1756-137X

Keywords

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Case study
Publication date: 17 October 2012

Ramakrishna Velamuri, Yuan Ding and Jianhua Zhu

Entrepreneurship.

Abstract

Subject area

Entrepreneurship.

Study level/applicability

This case is suitable for MBA, EMBA and advanced undergraduate students.

Case overview

Noah Wealth Management was founded by Ms Wang Jingbo, a lady in her mid 30s with a team of less than 20 members in 2005. Exploiting market opportunities offered by a lack of good wealth management products and services, Noah grew rapidly from one branch office in 2005 to 59 branch offices in 2011, reaching a staff size of 1,031. Noah listed its shares on the New York Stock Exchange in November 2010. In 2011, Noah was ranked No. 38 among the 100 Top Potential Enterprises in China. Nonetheless, Noah faced several problems of internal management during the course of its fast expansion. In the first quarter financial report of 2012, Noah suffered a 52.6 percent decrease in net income over the corresponding period in 2011. Faced with a rapidly declining share price, Noah announced on May 22, 2012 a US $30 million share repurchase program.

Expected learning outcomes

The case supports a basic lesson on the entrepreneurial cycle, including assessing a business opportunity, resource mobilization, identifying a business model, growth of the venture, listing on the stock market, and subsequent growth challenges. Students can learn about some of the typical dilemmas faced by founders of entrepreneurial ventures, including how to maintain the corporate culture while growing fast and how to prevent members of the founding team from becoming bottlenecks to the development of the organization. The case can also provide management students with an overview of China's wealth management industry.

Supplementary materials

Teaching notes are available for educators only. Please contact your library to gain login details or email support@emeraldinsight.com to request teaching notes.

Details

Emerald Emerging Markets Case Studies, vol. 2 no. 8
Type: Case Study
ISSN: 2045-0621

Keywords

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Article
Publication date: 10 August 2010

Wu Xueli, Zhang Jianhua, Guan Xinping and Meng Hua

The purpose of this paper is to examine the criteria of uniqueness of the equilibrium point and the new stability criteria for stability of the equilibrium point. The new…

Abstract

Purpose

The purpose of this paper is to examine the criteria of uniqueness of the equilibrium point and the new stability criteria for stability of the equilibrium point. The new stability condition is dependent on the size of delays.

Design/methodology/approach

The global asymptotic stability of a class of delayed bi‐directional associative memory (BAM) neural networks is studied. Some new sufficient conditions are presented for the unique equilibrium point and the global stability of BAM neural networks with time delays by constructing Lyapunov functions and using the linear matrix inequality. A numerical example is presented to illustrate the effectiveness of the theoretical results.

Findings

Based on the mathematical method and matrixes inequality skill, some criteria are obtained which contain the unique equilibrium point and the global stability of BAM neural networks.

Research limitations/implications

The paper proposes the new Lyapunov function and new skill to compose matrixes inequality.

Practical implications

A very useful method for BAM neural network to judge the uniqueness of the equilibrium point and stability.

Originality/value

The new mathematical model is proposed about the production process, and the new control method is used in the temperature system for a double layers welded pipe in welding process.

Details

Kybernetes, vol. 39 no. 8
Type: Research Article
ISSN: 0368-492X

Keywords

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Article
Publication date: 26 February 2018

Abdul Waheed and Yang Jianhua

The purpose of this paper is to investigate the relationship between e-marketing (eM) and consumers’ buying behavior particularly exploratory buying behavior tendencies…

Abstract

Purpose

The purpose of this paper is to investigate the relationship between e-marketing (eM) and consumers’ buying behavior particularly exploratory buying behavior tendencies (EBBT) with moderating effect of a gender in the context of China.

Design/methodology/approach

Structural equation modeling using SPSS/AMOS was majorly applied to ascertain the relationship and hypotheses testing. First, the correlation of eM toward EBBT is examined using five factors: internet marketing (IM), e-mail marketing (EMa), intranet marketing (IMa), extranet marketing (EM), and mobile marketing (MM). Second, the relationship of each dimension of the eM model is determined autonomously to ensure the importance of such emerging technologies in marketing communications. Third, the effect of gender as a moderator is measured. To this end, primary data were collected through random distribution of the questionnaires among 1,600 consumers particularly students of the universities between February 2016 and August 2016 within North China.

Findings

The findings revealed that eM has a significant correlation on consumers’ EBBT. The comprehensive analysis of each factor of eM, i.e., IM, EMa, IMa, EM, and MM is positively correlated to EBBT. The present study revealed that gender did not moderate among the relationships of eM and EBBT. Additionally, study furnishes practical directions on how managers can utilize such emerging and revolutionary technologies in marketing activities to probe, understand, and reinforce consumers’ buying behavior.

Research limitations/implications

The research has limitations related to geographical location and sample size which thus limits the widespread generalization.

Practical implications

This study affirmed that organizations must engage the consumers using such technologies that are more likely acceptable by consumers in the present customer-oriented and digital era. The marketers must engage consumers the way they wish to be engaged by developing appropriate promotional strategies. The study provides possible implications both theoretical and managerial along with a contribution to the literature of eM and consumers’ buying behavior.

Social implications

Understanding the emerging technologies may furnish valuable insights for individuals to work well within Chinese SMEs.

Originality/value

The topic of eM has acknowledged as an evolving concept which is gaining an intense concern of both academician and practitioners. Therefore, more research mainly empirical work is still needed to probe the insights of eM across the globe. This study attempts to fulfill such need with empirical evidence together with an in-depth examination of eM determinants, collectively and autonomously.

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Article
Publication date: 2 November 2015

Pengbin Gao, Yexin Liu, Xiaoli Li and Yan Wang

This paper aims to unravel the technological innovation pattern in China’s aerospace industry. The technological innovation pattern of China’s aerospace industry is…

Abstract

Purpose

This paper aims to unravel the technological innovation pattern in China’s aerospace industry. The technological innovation pattern of China’s aerospace industry is identified and its theoretical foundation, structure, philosophy, formation and effects on the development of China’s aerospace industry are explored.

Design/methodology/approach

First, the theoretical foundation of synergy innovation of China’s aerospace industry is reviewed to further identify the technological innovation pattern. Second, Chinese ancient philosophy (dialectical thinking) is used to explain the structure and process of synergy innovation in China’s aerospace industry. Third, the formation process of synergy innovation is introduced, and, finally, the effects of synergy innovation are discussed.

Findings

The technological innovation pattern of China’s aerospace industry has undergone an evolutionary process. During this process, China’s aerospace firms have formed a unique technological innovation pattern, synergy innovation, under China’s special political and economic background. The synergy innovation has three characteristics, including original, integrated and application-based. The synergy innovation pattern application is one of the most important reasons behind the great achievements of China’s aerospace industry.

Originality/value

A unique technological innovation pattern, synergy innovation, is proposed for the first time. A new perspective for understanding innovation is provided by applying the Chinese dialectical thinking to decipher the philosophy of the technological innovation pattern. Based on this, this paper suggests that China’s aerospace industry should follow the situation and apply the synergy innovation pattern to achieve development and growth. This paper also illustrates a multi-method approach and emphasizes the different levels of organizing for innovation.

Details

Chinese Management Studies, vol. 9 no. 4
Type: Research Article
ISSN: 1750-614X

Keywords

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Article
Publication date: 27 July 2018

Jianhua Wang, May Chu, Yuan yuan Deng, Honming Lam and Jianjun Tang

The purpose of this paper is to investigate farmers’ intentions to comply with pesticide application standards based on an extended theory of planned behaviour (TPB).

Abstract

Purpose

The purpose of this paper is to investigate farmers’ intentions to comply with pesticide application standards based on an extended theory of planned behaviour (TPB).

Design/methodology/approach

Built on a TPB framework, it was examined how perceived behavioural control (PBC), behavioural goal (BG), behavioural attitude (BA) and subjective norm (SN) influenced farmers’ intention to comply with pesticide application standards. Data of 986 farmers from five major agricultural provinces in China were collected following a stratified random sampling method. Structural equation modelling was employed for hypothesis testing and analysis.

Findings

The results showed that PBC, BG, behavioural attitude and SN had positive impacts on farmers’ intention in abiding by the standards. Among them in determining farmers’ intention towards compliance with pesticide application standards, farmers’ PBC was found to be the most influential factor, while SN was the least influential factor.

Originality/value

The results indicated that the traditional TPB constructs had significant correlations with farmers’ intention to comply with pesticide standards, demonstrating the applicability of the TPB in the understanding of farmers’ decision-making in a developing country context. It is suggested that psychological factors should be taken into consideration in studying farmers’ decision-making.

Details

China Agricultural Economic Review, vol. 10 no. 4
Type: Research Article
ISSN: 1756-137X

Keywords

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