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Article
Publication date: 2 February 2015

Haitao Wu, Shijun Ding and Guanghua Wan

The purpose of this paper is to apply a poverty level decomposition approach to decompose the poverty by income sources and investigate the impact of government transfers…

Abstract

Purpose

The purpose of this paper is to apply a poverty level decomposition approach to decompose the poverty by income sources and investigate the impact of government transfers on income inequality and rural poverty.

Design/methodology/approach

This paper uses the decomposition method of inequality and the decomposition method of poverty level by resource endowments to decompose the overall inequality and the overall poverty by income sources.

Findings

It is found that unequal income distribution rather than income endowments is mainly responsible for the existence of poverty. Government transfers and relief income, aiming at the poor, help alleviate inequality and poverty, but are not targeting the poorest. Unequal distribution of production subsidies actually lead to higher poverty incidence.

Research limitations/implications

This paper has revealed that the poverty issue cannot be resolved with economic development alone if the issues including the inequality in income distribution are not solved. It is important to make government transfers/subsidies pro-poor.

Originality/value

A poverty level decomposition approach is first used to decompose the poverty by income sources in China.

Details

China Agricultural Economic Review, vol. 7 no. 1
Type: Research Article
ISSN: 1756-137X

Keywords

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Article
Publication date: 15 May 2017

Haitao Li, Chunchi Wu and Jian Shi

The purpose of this paper is to estimate the effects of liquidity on corporate bond spreads.

Abstract

Purpose

The purpose of this paper is to estimate the effects of liquidity on corporate bond spreads.

Design/methodology/approach

Using a systematic liquidity factor extracted from the yield spreads between on- and off-the-run Treasury issues as a state variable, the authors jointly estimate the default and liquidity spreads from corporate bond prices.

Findings

The authors find that the liquidity factor is strongly related to conventional liquidity measures such as bid-ask spread, volume, order imbalance, and depth. Empirical evidence shows that the liquidity component of corporate bond yield spreads is sizable and increases with maturity and credit risk. On average the liquidity spread accounts for about 25 percent of the spread for investment-grade bonds and one-third of the spread for speculative-grade bonds.

Research limitations/implications

The results show that a significant part of corporate bond spreads are due to liquidity, which implies that it is not necessary for credit risk to explain the entire corporate bond spread.

Practical implications

The results show that returns from investments in corporate bonds represent compensations for bearing both credit and liquidity risks.

Originality/value

It is a novel approach to extract a liquidity factor from on- and off-the-run Treasury issues and use it to disentangle liquidity and credit spreads for corporate bonds.

Details

China Finance Review International, vol. 7 no. 2
Type: Research Article
ISSN: 2044-1398

Keywords

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Article
Publication date: 2 October 2017

Haitao Qi, Zilong Liu and Yan Lang

The symmetrical valve is usually used in the hydraulic servo control system to control the asymmetrical cylinder, but this system’s structure involves asymmetry, and so…

Abstract

Purpose

The symmetrical valve is usually used in the hydraulic servo control system to control the asymmetrical cylinder, but this system’s structure involves asymmetry, and so its dynamic characteristics are asymmetrical, which causes issues in the control system of symmetric response. The purpose of this paper is to achieve the aim of symmetric control.

Design/methodology/approach

In this paper, the authors proposed a method that combined wavelet neural network (WNN) and model reference adaptive control. The reference model determined the dynamic response that the system was expected to achieve, and the WNN adaptive control made the system follow the reference model to achieve the purpose of symmetric control.

Findings

The experimental results show that the method can achieve a more accurate symmetric control and position control compared with the solutions via the classical PID control.

Originality/value

The proposed combination of the WNN and the reference model can effectively compensate for the asymmetry of dynamic response of the asymmetric cylinder in forward and return directions, which can be extended to deal with other classes of applications.

Details

Engineering Computations, vol. 34 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

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Article
Publication date: 26 May 2020

Bashir Osman and Haitao Zhu

Training centers and labs offer many applications suitable for beginners who want to know how to set and operate a computer numerical control (CNC) milling machine…

Abstract

Purpose

Training centers and labs offer many applications suitable for beginners who want to know how to set and operate a computer numerical control (CNC) milling machine. However, few applications address a basic understanding of the machining process founded on mathematical principals in line with new high-speed and high-precision machining technologies. The purpose of this paper is to present a complex mechanism in a simplified way, explaining the subject at an elementary level.

Design/methodology/approach

The authors have developed an application of the CNC milling machine in a Matlab/Simulink package, obtaining the appropriate parameters mathematically. The project developed an analytical method using Matlab code to test the step response (the actual cutting force) under various parameters to ensure comparability of the designed model. The analytical results are in line with the developed model. The Matlab/Simulink user interface allows the application to better explain machining for educational purposes. Furthermore, by combining this mathematical model and the fuzzy controller, the high-speed constant-force milling control model has a user interface for data entry. The addition of two kinds of fuzzy controllers (look-up table and Mamdani) achieve a more educational environment compared with existing models.

Findings

The developed technique can be used in CNC milling machine centers and laboratories. For virtual training purposes, this paper provides a two-stage educational model, giving students the necessary feedback on what they have learned at each stage from the beginning use of the CNC milling machine, with and without the controller. The system also offers to track the step-response analysis method. This method overcomes the shortage of milling processes modeled by the traditional transfer function, which more accurately establishes the relationship between cutting force and cutting parameters.

Practical implications

This technique can be used in the CNC machine centers and laboratory for teaching beginner students and trainees. Real data from the workshop had been used.

Originality/value

The earlier versions of this manuscript were presented in: JVE International LTD. Vibroengineering Procedia. +2017. 14.; IEEE 4th International Conference on Information Science and Control Engineering (ICISCE) +2017.

Details

Journal of Engineering, Design and Technology , vol. 18 no. 5
Type: Research Article
ISSN: 1726-0531

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Article
Publication date: 12 June 2017

Haitao Liu

The purpose of this paper is to present the basic solution of two collinear mode-I cracks in the orthotropic medium by the use of the non-local theory.

Abstract

Purpose

The purpose of this paper is to present the basic solution of two collinear mode-I cracks in the orthotropic medium by the use of the non-local theory.

Design/methodology/approach

Meanwhile, the generalized Almansi’s theorem and the Schmidt method are used. By the Fourier transform, it is converted to a pair of dual integral equations.

Findings

Numerical examples are provided to show the effects of the crack length, the distance between the two collinear cracks and the lattice parameter on the stress field near the crack tips in the orthotropic medium.

Originality/value

The present solution exhibits no stress singularity at the crack tips in the orthotropic medium.

Details

Multidiscipline Modeling in Materials and Structures, vol. 13 no. 1
Type: Research Article
ISSN: 1573-6105

Keywords

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Article
Publication date: 2 September 2019

Haitao Liu and Shuai Zhu

Based on the non-local piezoelectricity theory, this paper is concerned with two collinear permeable Mode-I cracks in piezoelectric materials subjected to the harmonic…

Abstract

Purpose

Based on the non-local piezoelectricity theory, this paper is concerned with two collinear permeable Mode-I cracks in piezoelectric materials subjected to the harmonic stress wave. The paper aims to discuss this issue.

Design/methodology/approach

According to the Fourier transformation, the problem is formulated into two pairs of dual integral equations, in which the unknown variables are the displacement jumps across the crack surfaces.

Findings

Finally, the dynamic non-local stress and the dynamic non-local electric displacement fields near the crack tips are obtained. Numerical results are provided to illustrate the effects of the distance between the two collinear cracks, the lattice parameter and the circular frequency of the incident waves on the entire dynamic fields near the crack tips, which play an important role in designing new structures in engineering.

Originality/value

Different from the classical solutions, the present solution exhibits no stress and electric displacement singularities at the crack tips in piezoelectric materials. It is found that the maximum stress and maximum electric displacement can be used as a fracture criterion.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 6
Type: Research Article
ISSN: 1573-6105

Keywords

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Article
Publication date: 24 August 2020

YuBo Sun, Juliang Xiao, Haitao Liu, Tian Huang and Guodong Wang

The purpose of this paper is to accurately obtain the deformation of a hybrid robot and rapidly enable real-time compensation in friction stir welding (FSW). In this…

Abstract

Purpose

The purpose of this paper is to accurately obtain the deformation of a hybrid robot and rapidly enable real-time compensation in friction stir welding (FSW). In this paper, a prediction algorithm based on the back-propagation neural network (BPNN) optimized by the adaptive genetic algorithm (GA) is presented.

Design/methodology/approach

Via the algorithm, the deformations of a five-degree-of-freedom (5-DOF) hybrid robot TriMule800 at a limited number of positions are taken as the training set. The current position of the robot and the axial force it is subjected to are used as the input; the deformation of the robot is taken as the output to construct a BPNN; and an adaptive GA is adopted to optimize the weights and thresholds of the BPNN.

Findings

This algorithm can quickly predict the deformation of a robot at any point in the workspace. In this study, a force-deformation experiment bench is built, and the experiment proves that the correspondence between the simulated and actual deformations is as high as 98%; therefore, the simulation data can be used as the actual deformation. Finally, 40 sets of data are taken as examples for the prediction, the errors of predicted and simulated deformations are calculated and the accuracy of the prediction algorithm is verified.

Practical implications

The entire algorithm is verified by the laboratory-developed 5-DOF hybrid robot, and it can be applied to other hybrid robots as well.

Originality/value

Robots have been widely used in FSW. Traditional series robots cannot bear the large axial force during welding, and the deformation of the robot will affect the machining quality. In some research studies, hybrid robots have been used in FSW. However, the deformation of a hybrid robot in thick-plate welding applications cannot be ignored. Presently, there is no research on the deformation of hybrid robots in FSW, let alone the analysis and prediction of their deformation. This research provides a feasible methodology for analysing the deformation and compensation of hybrid robots in FSW. This makes it possible to calculate the deformation of the hybrid robot in FSW without external sensors.

Details

Industrial Robot: the international journal of robotics research and application, vol. 47 no. 6
Type: Research Article
ISSN: 0143-991X

Keywords

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Article
Publication date: 7 August 2018

Dang Luo, Haitao Li and Qicun Qian

The purpose of this paper is to construct a key factors selection approach for a class of small-sample multi-factor cross-sectional data analysis (SMCDA) problem, which is…

Abstract

Purpose

The purpose of this paper is to construct a key factors selection approach for a class of small-sample multi-factor cross-sectional data analysis (SMCDA) problem, which is very common in productive practice and scientific research, such as coal-bed methane (CBM) content analysis, civil aircraft cost analysis, etc. Key factors selection is an important basic work for SMCDA problem; the proposed method is constructed to improve the accuracy and explanatory of the selected key factors.

Design/methodology/approach

Using grey system theory to solve SMCDA problem is more reasonable under few data and poor information. Therefore, this paper constructs a grey incidence analysis (GIA) model with rate of change to select the key factors of an SMCDA problem. The basic idea of the proposed method is to simulate time series by randomly sorting the selected samples, and to calculate the degree of grey incidence with rate of change by loop iterative algorithm, then to construct the degree matrix of grey incidence with rate of change, and finally by which, to utilise quantitative and qualitative analysis methods to select the key factors.

Findings

The experimental analysis of application cases demonstrates that the key factors of system’s characteristic can be successfully screened out by the proposed method, the results are consistent with actual conditions, and they have a clearer meaning and a better interpretability.

Practical implications

The method proposed in this paper could be utilised to select key factors for such a class of SMCDA problem, which has fewer observation samples (small-sample), which is influenced by a number of factors (multi-factor) and whose observation samples are placed randomly rather than by time (cross-sectional data). Taking the key influence factors of CBM content and the key driving factors of the vulnerability of agricultural drought in Henan as examples, the results proved the feasibility and superiority of this proposed method.

Originality/value

Most of the existing GIA models mainly focus on these classes of issues with time series data or panel data. However, few GIA models take SMCDA problem as the research object. In this paper, the authors develop the GIA model with rate of change according to the characteristics of SMCDA problem, and present some properties and application suggestions of the proposed method.

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Article
Publication date: 10 December 2019

Yongliang Jin, Jian Li, Bingxue Cheng, Dan Jia, Jiesong Tu, Shengpeng Zhan, Lian Liu and Haitao Duan

This paper aims to investigate the thermal oxidation behavior of trimethylolpropane trioleate (TMPTO) base oil when exposed to Fe surfaces.

Abstract

Purpose

This paper aims to investigate the thermal oxidation behavior of trimethylolpropane trioleate (TMPTO) base oil when exposed to Fe surfaces.

Design/methodology/approach

Samples of TMPTO bulk oil were placed in Fe vessels and heated in an oven to accelerate the oxidation at different time intervals, while others were placed in glass vessels and used as experimental controls. Subsequently, the physicochemical properties of the oxidized TMPTOs, including the kinematic viscosity and acid value, were measured and a structural analysis was conducted using the Raman and Fourier transform infrared (FTIR) techniques.

Findings

The results demonstrate that the TMPTO bulk oil exhibited an exponential increase in the kinematic viscosity along with the increasing acid value over the oxidation time. The Fe surface significantly increased the kinematic viscosity of TMPTO, while only mildly impacting its acid value compared with the experimental controls. The structural analysis results of the TMPTO suggest that the C = C and = C-H bonds were the vulnerable sites. Furthermore, the results suggest that the Fe surface evidently accelerates the chemical reactions of the C = C and the = C-H bonds, and less alcohols and more carbonyl products were identified in the oil samples that were heated in the Fe vessels.

Originality/value

The results demonstrate that the Fe surfaces affected the oxidation behavior of the TMPTO base oil, and an interaction mechanism between the Fe and the TMPTO is developed.

Details

Industrial Lubrication and Tribology, vol. 72 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 9 June 2020

Ewan Wright and Haitao Wei

The worldwide expansion of higher education participation has destabilised the value of higher education as a currency of opportunity. An increasing number of graduates…

Abstract

Purpose

The worldwide expansion of higher education participation has destabilised the value of higher education as a currency of opportunity. An increasing number of graduates are experiencing the precarity of unemployment, under-employment and low salaries. This study aimed to investigate how university students in China understand and respond to the changing relationship between higher education and career opportunities.

Design/methodology/approach

The research team conducted 100 in-depth interviews with final-year undergraduates at one elite and one lower-tier university in a metropolitan city in Guangdong Province.

Findings

The students were acutely aware of fierce competition in the graduate labour market. When asked “what matters most” for post-graduation career prospects, they identified elite universities and high-status fields of study as “traditional” currencies of opportunity. Nonetheless, to stand out in a competitive environment, they perceived a growing need to supplement higher education credentials through university experiences (internships, student governance, study abroad programmes), party membership, personal connections and (overseas) postgraduate education. Moreover, in a “race to the top”, they discussed how qualitatively distinctive university experiences and elite postgraduate education are “new” currencies of opportunity for high-status professional employment.

Originality/value

The study demonstrates how intensified competition for graduate employment can result in an “opportunity trap”. The students were participating in an “arms race” to accumulate positional advantages for their post-graduation careers. The net impact of such efforts on a systemic level is to create an upward spiral in what students are expected to do in preparation for their post-graduation careers and further destabilise the value of higher education as a currency of opportunity.

Details

Asian Education and Development Studies, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2046-3162

Keywords

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