Qinjie Yang, Guozhe Shen, Chao Liu, Zheng Wang, Kai Zheng and Rencheng Zheng
Steer-by-wire (SBW) system mainly relies on sensors, controllers and motors to replace the traditionally mechanical transmission mechanism to realize steering functions. However…
Abstract
Purpose
Steer-by-wire (SBW) system mainly relies on sensors, controllers and motors to replace the traditionally mechanical transmission mechanism to realize steering functions. However, the sensors in the SBW system are particularly vulnerable to external influences, which can cause systemic faults, leading to poor steering performance and even system instability. Therefore, this paper aims to adopt a fault-tolerant control method to solve the safety problem of the SBW system caused by sensors failure.
Design/methodology/approach
This paper proposes an active fault-tolerant control framework to deal with sensors failure in the SBW system by hierarchically introducing fault observer, fault estimator, fault reconstructor. Firstly, the fault observer is used to obtain the observation output of the SBW system and then obtain the residual between the observation output and the SBW system output. And then judge whether the SBW system fails according to the residual. Secondly, dependent on the residual obtained by the fault observer, a fault estimator is designed using bounded real lemma and regional pole configuration to estimate the amplitude and time-varying characteristics of the faulty sensor. Eventually, a fault reconstructor is designed based on the estimation value of sensors fault obtained by the fault estimator and SBW system output to tolerate the faulty sensor.
Findings
The numerical analysis shows that the fault observer can be rapidly activated to detect the fault while the sensors fault occurs. Moreover, the estimation accuracy of the fault estimator can reach to 98%, and the fault reconstructor can make the faulty SBW system to retain the steering characteristics, comparing to those of the fault-free SBW system. In addition, it was verified for the feasibility and effectiveness of the proposed control framework.
Research limitations/implications
As the SBW fault diagnosis and fault-tolerant control in this paper only carry out numerical simulation research on sensors faults in matrix and laboratory/Simulink, the subsequent hardware in the loop test is needed for further verification.
Originality/value
Aiming at the SBW system with parameter perturbation and sensors failure, this paper proposes an active fault-tolerant control framework, which integrates fault observer, fault estimator and fault reconstructor so that the steering performance of SBW system with sensors faults is basically consistent with that of the fault-free SBW system.
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Kai Zheng, Xianjun Yang, Yilei Wang, Yingjie Wu and Xianghan Zheng
The purpose of this paper is to alleviate the problem of poor robustness and over-fitting caused by large-scale data in collaborative filtering recommendation algorithms.
Abstract
Purpose
The purpose of this paper is to alleviate the problem of poor robustness and over-fitting caused by large-scale data in collaborative filtering recommendation algorithms.
Design/methodology/approach
Interpreting user behavior from the probabilistic perspective of hidden variables is helpful to improve robustness and over-fitting problems. Constructing a recommendation network by variational inference can effectively solve the complex distribution calculation in the probabilistic recommendation model. Based on the aforementioned analysis, this paper uses variational auto-encoder to construct a generating network, which can restore user-rating data to solve the problem of poor robustness and over-fitting caused by large-scale data. Meanwhile, for the existing KL-vanishing problem in the variational inference deep learning model, this paper optimizes the model by the KL annealing and Free Bits methods.
Findings
The effect of the basic model is considerably improved after using the KL annealing or Free Bits method to solve KL vanishing. The proposed models evidently perform worse than competitors on small data sets, such as MovieLens 1 M. By contrast, they have better effects on large data sets such as MovieLens 10 M and MovieLens 20 M.
Originality/value
This paper presents the usage of the variational inference model for collaborative filtering recommendation and introduces the KL annealing and Free Bits methods to improve the basic model effect. Because the variational inference training denotes the probability distribution of the hidden vector, the problem of poor robustness and overfitting is alleviated. When the amount of data is relatively large in the actual application scenario, the probability distribution of the fitted actual data can better represent the user and the item. Therefore, using variational inference for collaborative filtering recommendation is of practical value.
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Zhengfeng Cao, Yanqiu Xia, Chuan Chen, Kai Zheng and Yi Zhang
This paper aims to explore polyaniline (PANI) as a lubricant additive to improve the anti-corrosion and tribological properties of ionic liquids (ILs) for actual applications.
Abstract
Purpose
This paper aims to explore polyaniline (PANI) as a lubricant additive to improve the anti-corrosion and tribological properties of ionic liquids (ILs) for actual applications.
Design/methodology/approach
ILs were synthesized by dissolving lithium salts in synthetic oil and were used as a base oil to prepare ILs-based greases. PANI was used as an additive. The tribological properties were investigated in detail and the anti-corrosion ability was also assessed via salt spray test. After friction test, the worn surfaces were characterized by scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy to analyze the lubrication mechanisms.
Findings
PANI not only reduces the corrosion but also improves the friction reduction and anti-wear abilities of the ILs-based greases. The analysis indicates that the protective films generated on the worn surfaces were responsible for the preferable anti-corrosion and tribological properties.
Originality/value
This paper provides an effective approach to improve the anti-corrosion and tribological properties of ILs for actual applications.
Peer review
The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-11-2019-0469/
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Xiaoning Li, Xinbo Liao, Qingwen Zhong, Kai Zheng, Shaoxing Chen, Xiao-Jun Chen, Jin-Xiu Zhu and Hongyuan Yang
The purpose of this paper is to analyze the influencing factors of patients’ financial burden through a case study of hospital on public‒private partnerships (PPP) model (Chaonan…
Abstract
Purpose
The purpose of this paper is to analyze the influencing factors of patients’ financial burden through a case study of hospital on public‒private partnerships (PPP) model (Chaonan Minsheng Hospital of Guangdong Province) and provide some useful information to policymakers for better development of hospitals on PPP model.
Design/methodology/approach
There are total six indicators that are defined as patients’ financial burden, basing on the policy of “indicators of medical quality management and control on the third level large general hospital (2011 edition),” issued by Chinese Government. In total, 23 potentially influencing factors of patients’ financial burden for hospital on PPP model were chosen from the above policy. The five-year (2007‒2011) data for the above 29 indicators come from statistic department of hospital on PPP model. Grey relational analysis (GRA) was applied to analyze the influencing factors of patients’ financial burden for hospital on PPP model.
Findings
A clear rank of influencing factors of patients’ financial burden is obtained and suggestions are provided from results of GRA, which provide reference for policymakers of hospital on PPP model. The five main influencing factors of patients’ financial burden for hospital on PPP model, in sequence, are rescuing critical ill patients on emergency, rescuing critical ill inpatients, inpatient bed occupancy rate, working days per bed and medical building area.
Originality/value
The study on the influencing factors of patients’ financial burden for hospital on PPP model not only provides decision-making for policymaker of hospital and controlling of medical expenditure but also contributes to release patients’ financial burden for hospitals on PPP model.
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Kai‐Wen Zheng, Chih‐Hung Tsai, Rong‐Kwei Li, Ching‐Piao Chen and Shih‐Chieh Tsai
As the flourish of today’s supply chain, the traditional model of replenishment will cause accumulation of excessive inventory to the retailers and customers, or cause shortages…
Abstract
As the flourish of today’s supply chain, the traditional model of replenishment will cause accumulation of excessive inventory to the retailers and customers, or cause shortages and inability to meet the demands. To solve this problem, Theory of Constraints (TOC) proposed the replenishment model of demand‐pull, combined with the establishment of factory‐warehouse to achieve performance improvement. In the absence of empirical research, this study applied the Bean Game developed by Dr. Goldratt to design a supply chain system for different scenarios, in order to allow players and managers better understanding and supporting the TOC replenishment method through the operations of the game.
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Zongshui Wang, Wei Liu, Zhuo Sun and Hong Zhao
Building on social media and destination brand-related literature, this study aims to explore World Heritage Sites’ (WHSs) brand diffusion and formation process from long-term and…
Abstract
Purpose
Building on social media and destination brand-related literature, this study aims to explore World Heritage Sites’ (WHSs) brand diffusion and formation process from long-term and short-term perspectives, which includes brand diffusion, user-generated content (UGC), opinion leaders and brand events’ impact.
Design/methodology/approach
This study uses a mixed-method including text mining, keyword analysis and social network analysis to explore the brand formation process of four popular WHSs in Beijing, namely, the Palace Museum, Great Wall, Summer Palace and Temple of Heaven and more than 10,000,000 users’ data on Sina Weibo has been implemented to uncover the underlying social media branding mechanism.
Findings
The results show that the number of postings keeps in a stable range in most months, but, in general, there are no common rules for changing trends among the four WHSs; long-term high-frequency keywords related to history and culture account for a higher percentage; different kinds of accounts have varying impacts on information diffusion, in which media accounts lead to a bigger influence. However, more followers do not necessarily mean more interactions and most of the interaction ratio is much lower than 0.01000; brand events facilitate brand dissemination and have an impact on the creation of UGC.
Practical implications
This study is valuable for destination marketers to deeper understand brand diffusion and formation and provides valuable insights for developing effective destination marketing strategies.
Originality/value
Unlike previous studies that only concern a few parts of destination brand formation via social media (e.g. brand diffusion, brand events or opinion leaders’ impact), this study takes a more comprehensive perspective by systematically analyzing the brand formation process of WHSs on social media. By considering both long-term diffusion and short-term representative events, this study provides a more holistic understanding of the branding mechanism.
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Jonathan Brookfield, Ren‐Jye Liu and John Paul MacDuffie
This case aims to examine how Taiwan's bicycle industry has persevered against increasingly severe competitive challenges from Chinese companies. The Taiwan firms have created…
Abstract
Purpose
This case aims to examine how Taiwan's bicycle industry has persevered against increasingly severe competitive challenges from Chinese companies. The Taiwan firms have created innovative, high value‐added products and transformed the organization of production through a new version of cooperative competition. The case seeks to show how established producers may counter‐attack when faced with the strong challenges of low‐cost competitors.
Design/methodology/approach
The authors, all experts on Taiwanese manufacturing and business processes, examine the characteristics of an integrated, co‐innovative, cooperative supplier network, named the A‐Team.
Findings
The paper finds that, broadly speaking, integrated, co‐innovative supplier networks have two basic features that differentiate them from traditional modular, symbiotic supplier networks. First, whereas traditional supplier systems have emphasized cost control, integrated, co‐innovative supplier networks appear to be more focused on value creation through co‐innovation. Secondly, by adopting a more integrated network structure, such supplier networks appear to have a greater ability to resist imitation.
Practical implications
Based on Taiwan's bicycle industry, there seem to be five basic conditions for establishing a successful integrated, co‐innovative supplier network. There must be: a strong awareness of industry risks and/or prospects; trust among network members; long‐term interactive cooperative relationships; a desire to learn, and extensive communication, including substantial face‐to‐face communication.
Originality/value
For producers faced with the challenge of coping with the threat of low‐cost competition, co‐innovation within an integrated supplier network may be quite helpful. By working to coordinate the innovation efforts of assemblers and suppliers, Taiwan's A‐Team has laid a good foundation. While some initiatives are still in the early stages, as a result of the A‐Team's work to date, A‐team membership has increased and the group has received considerable recognition both at home and abroad.
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Fei Fan, Kara Chan, Yan Wang, Yupeng Li and Michael Prieler
Online influencers are increasingly used by brands around the globe to establish brand communication. This study aims to investigate the characteristics of social media content in…
Abstract
Purpose
Online influencers are increasingly used by brands around the globe to establish brand communication. This study aims to investigate the characteristics of social media content in terms of presentation style and brand communication among online influencers in China. The authors identified how characteristics of social media posts influence young consumers’ engagement with the posts.
Design/methodology/approach
The authors analyzed 1,779 posts from the Sina Weibo accounts of ten top-ranked online influencers by combining traditional content analysis with Web data crawling of audience engagement with social media posts.
Findings
Online influencers in China more frequently used photos than videos to communicate with their social media audience. Altogether 8% and 6% of posts carried information about promotion and event, respectively. Posts with promotional incentives as well as event information were more likely to engage audiences. Altogether 22% of the sampled social media posts mentioned brands. Posts with brand information, however, were less likely to engage audiences. Furthermore, having long text is more effective than photos/images in generating likes from social media audiences.
Originality/value
Combining content analysis of social media posts and engagement analytics obtained via Web data crawling, this study is, to the best of the authors’ knowledge, one of the first empirical studies to analyze influencer marketing and young consumers’ reactions to social media in China.
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Abstract
Purpose
The purpose of this paper is to find a new method to reinforce high-density polyethylene (HDPE) with polyacrylonitrile fibers (PAN). Furthermore, the crystallinity, viscoelasticity and thermal properties of HDPE composites have also been investigated and compared.
Design/methodology/approach
For effective reinforcing, samples with different content fillers were prepared. HDPE composites were prepared by melt blending with double-screw extruder prior to cutting into particles and the samples for testing were made using an injection molding machine.
Findings
With the addition of 9 Wt.% PAN fibers, it was found that the tensile strength and flexural modulus got the maximum value in all HDPE composites and increased by 1.2 times than pure HDPE. The shore hardness, storage modulus and vicat softening point of the composites improved continuously with the increase in the proportion of the fibers. The thermal stability and processability of composites did not change rapidly with the addition of PAN fibers. The degree of crystallinity increased with the addition of PAN fibers. In general, the composites achieve the best comprehensive mechanical properties with the fiber content of 9 Wt.%.
Practical implications
The fibers improve the strength of the polyethylene and enhance its ability to resist deformation.
Originality/value
The modified HDPE by PAN fibers in this study have high tensile strength and resistance to deformation and can be used as an efficient material in engineering, packaging and automotive applications.