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Article
Publication date: 24 August 2020

Yanxia Liu, Zhikai Hu and JianJun Fang

The three-axis magnetic sensors are mostly calibrated by scalar method such as ellipsoid fitting and so on, but these methods cannot completely determine the 12 parameters…

Abstract

Purpose

The three-axis magnetic sensors are mostly calibrated by scalar method such as ellipsoid fitting and so on, but these methods cannot completely determine the 12 parameters of the error model. A two-stage calibration method based on particle swarm optimization (TSC-PSO) is proposed, which makes full use of the amplitude invariance and direction invariance of Earth’s magnetic field vector.

Design/methodology/approach

The TSC-PSO designs two-stage fitness function. Stage 1: design a fitness function of the particle swarm by the amplitude invariance of the Earth’s magnetic field to obtain a preliminary error matrix G and the bias error B. Stage 2: further design the fitness function of the particle swarm by the invariance of the Earth’s magnetic field to obtain a rotation matrix R, thereby determining the error matrix uniquely.

Findings

The proposed TSC-PSO can completely determine 12 unknown parameters in error model and further decrease the maximum fluctuation error of the Earth’s magnetic field amplitude and the absolute error of heading.

Practical implications

The proposed TSC-PSO provides an effective solution for three-axis magnetic sensor error compensation, which can greatly reduce the price of magnetic sensors and be used in the fields of Earth’s magnetic survey, drilling and Earth’s magnetic integrated navigation.

Originality/value

The proposed TSC-PSO has significantly improved the magnetic field amplitude and heading accuracy and does not require additional heading reference. In addition, the method is insensitive to noise and initialization conditions, has good robustness and can converge to a global optimum.

Details

Sensor Review, vol. 40 no. 5
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 6 November 2018

Yanxia Liu, JianJun Fang and Gang Shi

The sources of magnetic sensors errors are numerous, such as currents around, soft magnetic and hard magnetic materials and so on. The traditional methods mainly use…

Abstract

Purpose

The sources of magnetic sensors errors are numerous, such as currents around, soft magnetic and hard magnetic materials and so on. The traditional methods mainly use explicit error models, and it is difficult to include all interference factors. This paper aims to present an implicit error model and studies its high-precision training method.

Design/methodology/approach

A multi-level extreme learning machine based on reverse tuning (MR-ELM) is presented to compensate for magnetic compass measurement errors by increasing the depth of the network. To ensure the real-time performance of the algorithm, the network structure is fixed to two ELM levels, and the maximum number of levels and neurons will not be continuously increased. The parameters of MR-ELM are further modified by reverse tuning to ensure network accuracy. Because the parameters of the network have been basically determined by least squares, the number of iterations is far less than that in the traditional BP neural network, and the real-time can still be guaranteed.

Findings

The results show that the training time of the MR-ELM is 19.65 s, which is about four times that of the fixed extreme learning algorithm, but training accuracy and generalization performance of the error model are better. The heading error is reduced from the pre-compensation ±2.5° to ±0.125°, and the root mean square error is 0.055°, which is about 0.46 times that of the fixed extreme learning algorithm.

Originality/value

MR-ELM is presented to compensate for magnetic compass measurement errors by increasing the depth of the network. In this case, the multi-level ELM network parameters are further modified by reverse tuning to ensure network accuracy. Because the parameters of the network have been basically determined by least squares, the number of iterations is far less than that in the traditional BP neural network, and the real-time training can still be guaranteed. The revised manuscript improved the ELM algorithm itself (referred to as MR-ELM) and bring new ideas to the peers in the magnetic compass error compensation field.

Details

Sensor Review, vol. 39 no. 1
Type: Research Article
ISSN: 0260-2288

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Article
Publication date: 12 August 2019

Gang Shi, Xisheng Li, Zhe Wang and Yanxia Liu

The magnetometer measurement update plays a key role in correcting yaw estimation in fusion algorithms, and hence, the yaw estimation is vulnerable to magnetic…

Abstract

Purpose

The magnetometer measurement update plays a key role in correcting yaw estimation in fusion algorithms, and hence, the yaw estimation is vulnerable to magnetic disturbances. The purpose of this study is to improve the ability of the fusion algorithm to deal with magnetic disturbances.

Design/methodology/approach

In this paper, an adaptive measurement equation based on vehicle status is derived, which can constrain the yaw estimation from drifting when vehicle is running straight. Using this new measurement, a Kalman filter-based fusion algorithm is constructed, and its performance is evaluated experimentally.

Findings

The experiments results demonstrate that the new measurement update works as an effective supplement to the magnetometer measurement update in the present of magnetic disturbances, and the proposed fusion algorithm has better yaw estimation accuracy than the conventional algorithm.

Originality/value

The paper proposes a new adaptive measurement equation for yaw estimation based on vehicle status. And, using this measurement, the fusion algorithm can not only reduce the weight of disturbed sensor measurement but also utilize the character of vehicle running to deal with magnetic disturbances. This strategy can also be used in other orientation estimation fields.

Details

Sensor Review, vol. 39 no. 5
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 16 September 2013

Weimin Li, Yanxia Wu, Xiaobo Wang and Weimin Liu

The purpose of this paper is to study the antirust, tribological performance and anti-wear (AW) mechanism of the of soybean lecithin (SL) as a kind of multifunctional…

Abstract

Purpose

The purpose of this paper is to study the antirust, tribological performance and anti-wear (AW) mechanism of the of soybean lecithin (SL) as a kind of multifunctional lubricant additive.

Design/methodology/approach

As a kind of multifunctional lubricant additive, the antirust performance of SL was tested according to ASTM D 665, and meanwhile, its tribological performances were also evaluated by Optimol SRV-I oscillating reciprocating friction and wear tester and four ball tester. The worn steel surfaces were investigated by scanning electron microscope (SEM) and X-ray photoelectron spectroscopy (XPS).

Findings

The results showed that the SL exhibited excellent antirust properties in different base stock, and could effectively improve the AW and extreme pressure (EP) performances. The results of SEM and XPS indicated that a protective film was formed between steel-steel friction pair during the tribological test.

Originality/value

This paper first investigated the antirust properties and the tribological mechanism of the SL as a kind of multifunctional lubricant additive, which can be very useful and will promote the application of SL in lubricant industry.

Details

Industrial Lubrication and Tribology, vol. 65 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 19 October 2012

Yanxia Zhang and Mavis Maclean

The economic reforms which turned the centrally planned economy to a market economy have profoundly changed the tripartite relationship between the state, work unit, and…

Abstract

Purpose

The economic reforms which turned the centrally planned economy to a market economy have profoundly changed the tripartite relationship between the state, work unit, and citizen in urban China and brought significant changes to the institutional care provision for young children. The aim of this paper is to investigate the changes to the institutional care since 1980, with particular emphasis on the most recent years from mid‐1990s, and explore how the institutional care has changed over the recent decades without a clear institutional basis.

Design/methodology/approach

The analysis draws on second‐hand materials from published literature, a range of longitudinal national and local statistics and policy documents, and also on first‐hand information which was collected in Beijing from in‐depth interviews with key informants and case studies of different kinds of kindergartens.

Findings

The paper finds that the previous work‐unit based public care system has changed to a much more complicated care mix in which the roles of the state, employer, community, market and the informal sector of the family in terms of provision and funding have all changed significantly.

Social implications

The findings of this paper may help to inform appropriate policy responses in Chinese child care provision. The study suggests that formal care provision should be expanded towards universal access regardless of people's income and employment status in China.

Originality/value

The paper questions and complicates the “state withdrawal” representation of social welfare change and argues that it is not “the state” but “the work unit and community organization” retreat from public care provision. It also argues that the change in the role of the state has been multifaceted, and not a simple one‐directional movement of marketization in which the state retreated from welfare provision in entirety.

Details

International Journal of Sociology and Social Policy, vol. 32 no. 11/12
Type: Research Article
ISSN: 0144-333X

Keywords

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Article
Publication date: 10 October 2016

Jiangtao Li, Jianyue Ji and Yanxia Wang

Efficiency of a commercial bank affects both its competitiveness and the role it plays in the process of economic development. Although great efforts have been exerted in…

Abstract

Purpose

Efficiency of a commercial bank affects both its competitiveness and the role it plays in the process of economic development. Although great efforts have been exerted in developing the various aspects of banking efficiency, there seems to be a lack of research on examining the impact of the bank efficiency from the employee wage perspective. The mechanism of how employee wage affects commercial bank efficiency and the relationship between the two were analyzed in this paper. Based on the growing body of research on efficiency in banking, the aim of this paper is to examine if competitiveness of employee wages at any commercial bank has any impact on the bank efficiency score.

Design/methodology/approach

The method used was quantitative analysis, which was based on comparing the evaluated efficiencies of the banks with employee wages published in the bank reports. The empirical data in this paper were based on 16 Chinese listed commercial banks from 2004 to 2012. The per capita wage of commercial banks was selected as the wage indicator, and the efficiency value obtained by the slack-based measure (SBM) model was selected as the efficiency indicator. According to the calculated data, the Tobit regression model was built to analyze the relationship between employee wage and commercial bank efficiency.

Findings

The research results show that employee wage is the key variable that influences the efficiency of Chinese commercial banks, and the inverted U-shaped relationship between employee wage and commercial banks efficiency shows up.

Practical implications

The wage structure data of the composition of basic pay and bonus were not available at the time of conducting the research. Per capita wages were used instead to reflect the employee wage levels of Chinese banks.

Originality/value

This study can provide some help for the banking industry by analyzing the wage levels from the perspective of efficiency and also further enriches the theoretical system of the relationship between employee wage and bank efficiency.

Details

Journal of Chinese Human Resource Management, vol. 7 no. 2
Type: Research Article
ISSN: 2040-8005

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Article
Publication date: 19 October 2012

Yanxia Zhang and Wei‐Jun. Jean Yeung

Asia's traditional experiences with care provision differ considerably from those of the West given the prevalent family‐based social norms about care and policies in this…

Abstract

Purpose

Asia's traditional experiences with care provision differ considerably from those of the West given the prevalent family‐based social norms about care and policies in this region. In recent decades, Asia has experienced profound social and demographic transformations and is thus faced with significant challenges around care. However, care in Asian countries is a relatively less studied topic. There is an urgent need for a comparative study on recent policy and practice changes in care for the elderly and young children in different regions of Asia. The purpose of this special issue is to examine complicated boundary shift in care provision and financing between the state, market, community and family in East, Southeast and South Asia and to explore the implications of these changes in care policies and practices for social stratification by class and gender in Asia.

Design/methodology/approach

The introduction to this special issue gives an overview of the social and demographic transformations and new strains on care in Asia as a background and introduces the framework of welfare mix employed in this special issue, especially the concepts of social care and the welfare/care diamond.

Findings

The introduction summarizes the variations in regard to the governance and provision of care between different Asian countries and compares the differences in the state involvement between Asia and Europe.

Originality/value

The authors also discuss some of their contributions to methodological approaches and analytical frameworks in studying care and the implications of the current research for future studies.

Details

International Journal of Sociology and Social Policy, vol. 32 no. 11/12
Type: Research Article
ISSN: 0144-333X

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Article
Publication date: 13 November 2018

Yanxia Wang, Chih-Chieh Chen, Luo Lu, Robert Eisenberger and Patricia Fosh

The purpose of this paper is to promote a wider understanding of the importance of distinguishing between presenteeism behavior and its motivation and between the…

Abstract

Purpose

The purpose of this paper is to promote a wider understanding of the importance of distinguishing between presenteeism behavior and its motivation and between the avoidance and approach dimensions of motivation, and to rectify the neglect of presenteeism’s antecedents (in particular, situational ones). It develops a theoretical model that explains how situational antecedents affect presenteeism – conventionally defined as attending work while ill.

Design/methodology/approach

An ordinary least-squares regression-based path analysis is employed to analyze the findings of a sample of 277 employees in service organizations in southwestern China.

Findings

Findings demonstrate that the situational factor, leader–member exchange (LMX), is positively related to the approach dimension of presenteeism motivation and that of workload moderates the positive link between presenteeism motivation and behavior, such that employees who experience higher workload more frequently display presenteeism behavior.

Practical implications

Findings suggest that managers should be prudent when developing relationships with their subordinates and consider the ways in which they may most effectively encourage employees to support their organization.

Originality/value

This is the first study to consider LMX and workload as situational antecedents of presenteeism motivation and behavior.

Details

Journal of Managerial Psychology, vol. 33 no. 7/8
Type: Research Article
ISSN: 0268-3946

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Article
Publication date: 18 June 2021

Ying Song, Wenyu Wu and Dario Miocevic

The literature shows that e-commerce adoption brings many benefits to farmers and agricultural businesses. However, the literature offers very limited guidance on the most…

Abstract

Purpose

The literature shows that e-commerce adoption brings many benefits to farmers and agricultural businesses. However, the literature offers very limited guidance on the most effective ways for them to utilize e-commerce platforms. In this study, we unfold how a farmer's choice between endogenous (their own) vs. exogenous (third-party) e-commerce platforms should be aligned with the external (support from agricultural cooperative) and internal (usage of quality labels) resources they can leverage and the performance goals they want to achieve (market expansion vs. price premium).

Design/methodology/approach

Our study draws on transaction cost economics (TCE) and resource-based theory (RBT) to test the conceptual model with data from a cross-sectional survey of 324 farmers from two provinces in PR China.

Findings

Our findings show that external and internal resources shed additional light on the effectiveness of endogenous vis-à-vis exogenous e-commerce platforms. For farmers who rely on exogenous e-commerce, support from an agricultural cooperative appears to be critical in increasing their market expansion. On the other hand, farmers seeking to earn a price premium should focus on developing their own e-commerce platforms, while at the same time emphasizing the quality labels of their agricultural products.

Practical implications

Farmers should pay close attention to the value-added benefits provisioned through farmers' cooperatives, as well as the benefits of acquiring quality labels for their agricultural products. However, the decision to utilize these resources should be aligned with the chosen e-commerce platform (endogenous vs. exogenous) as well as with the performance goal the farmer wants to achieve.

Originality/value

Our work goes beyond the traditional focus on transaction costs and efficiency of e-commerce channels and provides specific insights into when an endogenous or exogenous e-commerce model might provide benefits for farmers. On top of this, we argue and show that this decision should reside with the farmer's ability to leverage external and internal resources, envisioned through support from an agricultural cooperative and the quality labels of agricultural products.

Details

British Food Journal, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 16 March 2021

Xin Feng, Liming Sun, Yuehao Liu, Jiapei Li and Ye Wu

This paper aims to explore the development trend of OA articles and their advantages and disadvantages in the process of fighting the pandemic, and conduct a multi-level…

Abstract

Purpose

This paper aims to explore the development trend of OA articles and their advantages and disadvantages in the process of fighting the pandemic, and conduct a multi-level and multi-angle analysis of the relationship between publishing costs and the influence of OA articles.

Design/methodology/approach

This study first compares the total number of articles in Web of Science with the number of OA articles, and the total number of COVID-19 related articles with the total number of OA articles. Subsequently, using the methods of institutional cooperation co-occurrence network, keyword co-occurrence and multidimensional scale analysis, and using the literature on the topic of COVID-19 in CNKI (Chinese National Knowledge Infrastructure) as the data set, we generate visualized maps of research results distribution and keyword co-occurrence network with the help of the Statistical Analysis Toolkit for Infometrics (SATI)

Findings

The research results show that the citation frequency and use frequency of OA articles related to COVID-19 are significantly higher than that of non-OA articles. OA articles dominate in the anti-pandemic process, with a series of advantages such as short review cycle, timeliness, high social benefit, high participation and fast dissemination playing an important role. Under the model of author's non-payment for OA article, the degree of institutional cooperation and author cooperation is enhanced, which improves the fluidity of knowledge, strengthens close links between keywords and enhances significant academic influence; OA articles will continue to promote research in the field of COVID-19, but the lack of quality of some OA articles may hinder their development. Then OA articles will further focus on clinical medicine, and related results will continue to promote the development and communication of OA articles in this field.

Originality/value

Corresponding measures are also proposed for the existing problems of OA articles, to provide a reference for the publication and dissemination of OA articles in public health emergencies in the future.

Details

Library Hi Tech, vol. 39 no. 3
Type: Research Article
ISSN: 0737-8831

Keywords

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