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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 explicit…

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

Keywords

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 of the…

179

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

Content available
Article
Publication date: 4 May 2010

30

Abstract

Details

Kybernetes, vol. 39 no. 4
Type: Research Article
ISSN: 0368-492X

Abstract

Details

Kybernetes, vol. 39 no. 7
Type: Research Article
ISSN: 0368-492X

Article
Publication date: 23 April 2020

Jianjun Jia, Lili Shao, Zhenzhen Sun and Fang Zhao

This paper assesses how discretionary accruals (DAs) affect corporate cash savings policies and the motivation behind this cash saving behavior and, also whether the linkage…

Abstract

Purpose

This paper assesses how discretionary accruals (DAs) affect corporate cash savings policies and the motivation behind this cash saving behavior and, also whether the linkage between DAs and cash saving affect the market-perceived cash value.

Design/methodology/approach

We construct the measure of DAs using the previous five-year average information to investigate the association of DAs with the change in cash. Moreover, the Faulkender and Wang (2006) methodology is utilized to examine the market-perceived cash value in DAs.

Findings

The key finding is that firms with high DAs save significantly more cash. A one standard deviation increase in DAs saves cash by 12.59%. Furthermore, the value of cash is low for these firms. The effect is stronger in firms with poor governance but not present in financially constrained firms.

Research limitations/implications

The empirical evidence highlights DAs have negative effect on market-perceived cash value, which underscores the insight that managers manage earnings opportunistically using DAs.

Originality/value

Taken together, we provide more evidence on the literature of accruals in earnings manipulation.

Details

China Finance Review International, vol. 10 no. 4
Type: Research Article
ISSN: 2044-1398

Keywords

Case study
Publication date: 10 October 2022

Ou Bai, Xiaohua Yang, Keith O. Hunter and Bingwen Wang

This paper aims to first, identify the external and internal factors that a company needs to analyze when formulating its digital platform strategy. Based on the framework of…

Abstract

Learning outcomes

This paper aims to first, identify the external and internal factors that a company needs to analyze when formulating its digital platform strategy. Based on the framework of PESTNPG (political economic social and culture technological population and globalization) and internal analysis a company should analyze both internal and external factors to formulate its digital platform strategy. For companies from emerging markets the institutional-based market created by national or local governments is important for digital platform strategy. Second dynamic capability theory and its linkages to digital platform strategy. The dynamic capabilities view is considered as a primary theoretical lens in the strategy literature to analyze a company’s strategies to achieve sustainable competitive advantages. To carry out a successful digital platform strategy companies need to build strong dynamic capabilities to capture or create opportunities and reconfigure their resources simultaneously. Third the advantages and disadvantages of different digital platform strategies (i.e. an independent digital platform and online–offline integration platform) and the possible consequences and risks of different strategies. It is important to evaluate different types of digital platform strategies that require different capabilities in terms of business structure product structure revenue structure organizational structure and technology architecture. A company needs to link these capabilities to a digital platform strategy to enable the integration (or separation) of online business with offline business. It also increases the accuracy and efficiency of online business. Fourth key points of digital platform strategy implementation. Companies need to identify key profit models for their digital platform to promote business growth and financial returns. It is equally important to increase customer value by leveraging its digital exhibition platform and to learn to use digital technology to foster organizational dematerialization.

Case overview/Synopsis

Zhejiang Meorient Commerce & Exhibition Inc. (hereinafter referred to as “Meorient”) was a leading company in the exhibition industry in China. The unexpected outbreak of COVID-19 plunged Meorient into a state of emergency that forced it to fight for survival. Further, China had launched a national strategy of Digital China, which created new market opportunities for Meorient. As a result, Meorient gradually developed and launched its digital exhibition services in 2015. Meorient suffered significant losses in 2020 due to COVID-19 and had to formulate a new strategy based on a digital exhibition platform in 2021. Chairman Pan Jianjun had two options. One was a purely digital platform strategy without the original offline exhibition business. The other one was an online and offline integration strategy. Which option was the best way forward for Meorient? Pan had to make a choice. Some of the top management team members believed Meorient should completely transform into a digital platform company and provide comprehensive online digital exhibition services. Over the previous 20 years, Meorient had accumulated a large amount of data from domestic and foreign exhibitors and professional buyers and had gradually developed a digital exhibition platform. It was one of the companies that pioneered digital transformation within China’s exhibition industry. More conservative thinking held that Meorient's strategy should focus more narrowly on the integration of online and offline exhibition businesses. Toward the post-pandemic era, China’s national strategy of “Digital China” accelerated the development of digital infrastructures. During such critical transitional period, Meorient had to choose wisely if it was to sustain its profits or even survive.

Complexity academic level

The case is aimed at students in undergraduate, MBA, short course executive, EMBA or other executive education programs, especially where digital transformation is featured subject matter.

Supplementary materials

Teaching notes are available for educators only.

Subject code

CSS 11: Strategy

Details

Emerald Emerging Markets Case Studies, vol. 12 no. 3
Type: Case Study
ISSN:

Keywords

Article
Publication date: 8 June 2012

Hehua Wang, Zhigeng Fang and Jianjun Zhu

The purpose of this paper is to study the extensive method of grey target based on multi‐stage linguistic label, which is a hypothesis of incomplete information of the weight of…

258

Abstract

Purpose

The purpose of this paper is to study the extensive method of grey target based on multi‐stage linguistic label, which is a hypothesis of incomplete information of the weight of stage and decision maker.

Design/methodology/approach

For the incomplete weight information case, the weight model for the stage and decision maker is put forward based on the requirement of maximum difference among the alternatives. Also, the weight of the decision maker is estimated by the grey relationship method and the Euclid distance method.

Findings

As a result, the method of multiple stage grey target decision making based on linguistic label is suggested. In the incomplete information case, the weight model is suggested and the aggregation is put forward. The suggested method is clear and simple, which can be used in multi‐criteria decision making fields.

Practical implications

This paper offers a very useful result for multi‐attribute decision making.

Originality/value

This paper succeeds in studying the extensive method of grey target based on multi‐stage linguistic label, which is a hypothesis of incomplete information of the weight of stage and the decision maker.

Details

Kybernetes, vol. 41 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 7 September 2020

Ruijia Liu, Jianjun Yang and Feng Zhang

Prior studies have demonstrated the important role of coopetition in firms’ innovation. Based on the paradox perspective, this study aims to focus on technology transfer, the…

Abstract

Purpose

Prior studies have demonstrated the important role of coopetition in firms’ innovation. Based on the paradox perspective, this study aims to focus on technology transfer, the pre-innovation stage, to provide a supplementary understanding of the complementarity and contradictoriness of paradoxical coopetition, with the formal and informal governance mechanisms which are suitable with this understanding in coopetition.

Design/methodology/approach

This study conducted an original, multisource survey of 280 Chinese manufacturing firms. Hypotheses were tested through multiple regressions.

Findings

Coopetition has a positive impact on technology transfer between firms. Along with the increasing specificity of assets invested ex ante as a kind of formal governance mechanism, the relationship between coopetition and technology transfer becomes stronger. Meanwhile, inter-firm justice as an informal governance mechanism in the technology transfer process can be positively affected by coopetition between partners.

Originality/value

The study adds to the business-to-business coopetition literature on how to properly treat and use coopetition in technology transfer. Using the paradox perspective in the Chinese context, the findings emphasize the positive role of coopetition in the inter-firm technological exchange process, enriching the understanding of the complementary and contradictory features of paradoxical coopetition. To govern coopetitive relationships, the firms should also implement two fundamental governance mechanisms, that is, specialty asset and inter-firm justice.

Details

Journal of Business & Industrial Marketing, vol. 36 no. 5
Type: Research Article
ISSN: 0885-8624

Keywords

Article
Publication date: 31 January 2020

Leqin He, Shenjun Qin, Jianjun Liu, Wei Zhao and Tao Chang

From the atom economy and environmentally friendly point of views, the development of clean and green approaches using ionic liquids (ILs) as recyclable catalysts has attracted…

Abstract

Purpose

From the atom economy and environmentally friendly point of views, the development of clean and green approaches using ionic liquids (ILs) as recyclable catalysts has attracted increasing attention. The purpose of this study is to investigate the effect of task-specific ILs content on the one-pot three-component Biginelli reaction.

Design/methodology/approach

A series of halogen-free quaternary ammonium ILs functionalized with –SO3H group were prepared and characterized by 1H nuclear magnetic resonance (NMR), 13C NMR and electrospray ionization mass spectrometry. The ILs were used as catalysts for Biginelli reaction among aromatic aldehydes, urea or thiourea and β-dicarbonyl compounds. Anions and cations of ILs were varied to observe their effects on and contributions to the catalysts. The influencing factors, such as the amount of catalyst, solvent, reaction time and reaction temperature, were investigated.

Findings

The effect and contribution of cations of ILs were observed. Results showed that 3-(N, N-dimethylhexadecylammonium) propanesulfonic acid toluene sulfate ([DHPA][Tos]) showed comparable catalytic activity. Good adaptability to the reaction substrate and maximum product yield was observed when [DHPA][Tos] was used as catalyst. It was found that Biginelli reaction catalyzed by 10 mol% [DHPA][Tos] for 3 h under solvent-free conditions at 80 °C gave the best yield of 94%. Post-processing steps were simple, and the catalyst could be reused easily.

Originality/value

This paper demonstrates that ILs containing a long carbon chain and a bulky Tos anion efficiently promoted the reaction, in which the long carbon chains facilitate mass transfer in the reaction system.

Details

World Journal of Engineering, vol. 17 no. 1
Type: Research Article
ISSN: 1708-5284

Keywords

Content available
Article
Publication date: 17 August 2012

412

Abstract

Details

Grey Systems: Theory and Application, vol. 2 no. 2
Type: Research Article
ISSN: 2043-9377

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