Lijun Wan, Jiaqi Qiao and Quansheng Sun
The application of reinforcing old bridges by adding external prestressed steel bundles is becoming more and more widespread. However, the long-term safety performance test of the…
Abstract
Purpose
The application of reinforcing old bridges by adding external prestressed steel bundles is becoming more and more widespread. However, the long-term safety performance test of the strengthening method is rarely carried out. In this paper, the bearing capacity of a 420 m prestressed concrete (PC) continuous girder bridge after five years of strengthening is analyzed.
Design/methodology/approach
The bridge model of the bridge structure and strengthening scheme is established by the finite element software of the bridge. The theoretical load-bearing capacity of the bridge under the latest standard load grade is obtained by finite element analysis. The actual bearing capacity of the bridge is obtained by field test. Through the comparative analysis of theory and practice, the health state of the bridge after five years of reinforced operation is judged. The damage to the overall stiffness and external prestressing of the bridge is also analyzed.
Findings
The results of deflection and strain show that the stiffness and strength of the secondary side span and the middle span decrease slightly, and the maximum reduction of bearing capacity is 4.5%. The static stiffness of the whole bridge decreases as a result of cracks, and the maximum decrease is 21%. In the past five years, the relaxation loss of the external prestressing of the bridge is 3.31–3.97%, which is the main reason for the decrease in bearing capacity.
Originality/value
Through the joint analysis of the bridge stiffness and the loss of external prestressing, the strengthening condition of the bridge after five years of operation is effectively analyzed. The strengthening effect of the external prestressed steel beam strengthening method is analyzed, which can provide a reference for similar bridge strengthening.
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Bingbing Qi, Lijun Xu and Xiaogang Liu
The purpose of this paper is to exploit the multiple-Toeplitz matrices reconstruction method combined with quadratic spatial smoothing processing to improve the…
Abstract
Purpose
The purpose of this paper is to exploit the multiple-Toeplitz matrices reconstruction method combined with quadratic spatial smoothing processing to improve the direction-of-arrival (DOA) estimation performance of coherent signals at low signal-to-noise ratio (SNRs).
Design/methodology/approach
An improved multiple-Toeplitz matrices reconstruction method is proposed via quadratic spatial smoothing processing. Our proposed method takes advantage of the available information contained in the auto-covariance matrices of individual Toeplitz matrices and the cross-covariance matrices of different Toeplitz matrices, which results in a higher noise suppression ability.
Findings
Theoretical analysis and simulation results show that, compared with the existing Toeplitz matrix processing methods, the proposed method improves the DOA estimation performance in cases with a low SNR. Especially for the cases with a low SNR and small snapshot number as well as with closely spaced sources, the proposed method can achieve much better performance on estimation accuracy and resolution probability.
Research limitations/implications
The study investigates the possibility of reusing pre-existing designs for the DOA estimation of the coherent signals. The proposed technique enables achieve good estimation performance at low SNRs.
Practical implications
The paper includes implications for the DOA problem at low SNRs in communication systems.
Originality/value
The proposed method proved to be useful for the DOA estimation at low SNR.
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Liyi Zhang, Pinghao Ye, Qihua Liu and Lijun Rao
The information behavior of National Science and Technology Library (NSTL) electronic resources users in China has not been researched extensively. This paper aims to help…
Abstract
Purpose
The information behavior of National Science and Technology Library (NSTL) electronic resources users in China has not been researched extensively. This paper aims to help producers and providers collect information on user behavior and develop more electronic resources.
Design/methodology/approach
The study investigates NSTL users' behavior from seven “211 projects” universities in Wuhan, a city in central China. The questionnaire includes questions about respondents' basic information (i.e. educational level, discipline, etc.) and their information service requirements. Correlations among users' educational level, academic discipline, retrieval method, and literature use, among other variables, were analyzed.
Findings
The results show that most NSTL users are graduate students and young staff members. The number of users who use advanced retrieval and choose the criterion “literature's citation” to judge the literature's value increases slightly with the improvement of the educational level. There is higher demand for literature written in English in the disciplines of natural science, medicine, and engineering, and a certain proportion of demand for materials written in Japanese in the disciplines of medicine and engineering.
Practical implications
The findings suggest that electronic resource producers should offer more foreign literature and that providers should improve the quality of services.
Originality/value
The paper provides suggestions for further improvement of the NSTL to fulfil the information needs and requirements of users.
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Yilu Gong, Tantan Shao, Xiuming Wang, Xin Zhang, Zhijuan Sun and Lijun Chen
Fluorine and silicon materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose this study was to…
Abstract
Purpose
Fluorine and silicon materials have received the keen attention of many researchers because of their water repellency and low surface free energy. The purpose this study was to prepare vinyl acetate (VAc)-vinyl ester of neodecanoic acid (VeoVa 10) copolymer latex modified with fluorine and silicone monomer, which is emulsified with the novel surfactants of disodium laureth sulfosuccinate (MES) and octylphenol polyoxyethylene ether (OP-10).
Design/methodology/approach
A series of modified latices containing fluorine-silicon have been prepared by semi-continuous seeded emulsion polymerisation of mixed monomers of VAc, VeoVa10, hexafluorobutylmethacrylate (HFMA) and vinyltriethoxysilane (VTES) and emulsified by novel surfactants of MES and OP-10.
Findings
The optimum conditions for preparing the modified latex is as follows: the amount of the surfactant was 4.0 Wt.% and the mass ratio of the anionic and nonionic surfactant was 3:1; the dosage of initiator was 0.4 Wt.% and the mass ratio of the main monomer was 3:1; and the amounts of VTES and HFMA were 2.0 and 6.0 Wt.%, respectively. In comparison with the conventional latex, the hydrophobicity of latex film was improved further.
Originality/value
The modified p (VAC-VeoVa) latex is prepared via semi-continuous seeded emulsion polymerisation, which is emulsified with the novel mixed surfactants of MES and OP-10. There are two main innovations. One is that the novel p (VAC-VeoVa) latex containing fluorine-silicon is prepared successfully. The other is that the emulsifier is composed of the novel mixed surfactants of MES and OP-10.
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Ping Liu, Shouwei Li, Lijun Zhang and Wei Li
Building on the core concept of anthropomorphism and the empathy-helping theory, this research aims to examine how product anthropomorphism and buyer usage intentions affect…
Abstract
Purpose
Building on the core concept of anthropomorphism and the empathy-helping theory, this research aims to examine how product anthropomorphism and buyer usage intentions affect sellers’ pricing in second-hand markets as well as explore the psychological dynamics underlying these effects.
Design/methodology/approach
To test the hypotheses, a series of four experiments were conducted. Studies 1a (n = 140) and 1b (n = 140) employed a one-factor (product anthropomorphism: yes vs no) between-subject design and used chi-square analysis. Study 2 (n = 145) and Study 3 (n = 162) employed a 2 (usage intention: protective vs destructive) × 2 (product anthropomorphism: yes vs no) between-subject design and used two-way ANOVA and moderated mediation analysis.
Findings
The study found that even when potential buyers with destructive (vs protective) usage intentions offer higher prices, sellers of anthropomorphized (vs non-anthropomorphized) products are less willing to choose them (Studies 1a and 1b). When potential buyers express destructive (vs protective) usage intentions, sellers of anthropomorphized (vs non-anthropomorphized) products are less willing to offer discounts (Study 2), and the lowest price they are willing to accept is higher (Study 3). The level of perceived capacity for pain mediates these effects (Study 3).
Originality/value
These findings offer insights into the application of product anthropomorphism strategies and the second-hand transactions of used anthropomorphized products.
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Lijun Dong, Naichao Chen, Jiawen Liang, Tingting Li, Zhanlin Yan and Bing Zhang
The purpose of this study is to provide an in-depth understanding about the indoor-orbital electrical inspection robot, which is useful for motivating the further investigation on…
Abstract
Purpose
The purpose of this study is to provide an in-depth understanding about the indoor-orbital electrical inspection robot, which is useful for motivating the further investigation on the inspection of electrical equipment. Currently, electric energy has a strong correlation with the economic development of the country. Intelligent substations play an important role in the transmission and distribution of the electricity; the maintenance of the substation has attracted intensive attention due to the requirement of reliability and safety. The indoor-orbital electrical inspection robot has increasingly become the main tool to realize the unmanned. Hence, a systematic review is conducted systematically reviewing the current technical status of the indoor-orbital electrical inspection robot and discuss the existed problems.
Design/methodology/approach
In this paper, the most essential achievements in the field of indoor-orbital electrical inspection robots were reported to present the current status, and the mechanical structures and key inspective technologies were also discussed.
Findings
Four recommendations are provided from the analyzed review, which have made constructive comments on the overall structural design, functionality, intelligence and future development direction of the indoor-orbital electrical inspection robot, respectively.
Originality/value
To the best of the authors’ knowledge, this is the first systematic review study on indoor-orbital electrical inspection robots; it fills the theoretical gap and proffers design ideas and directions for the development of the indoor-orbital electrical inspection robot.
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Feiyan Han and Bo Li
E-commerce poverty alleviation (EPA) is an innovative poverty alleviation model in China. The institutional mechanisms of the e-commerce platform improve the effect of EPA and…
Abstract
Purpose
E-commerce poverty alleviation (EPA) is an innovative poverty alleviation model in China. The institutional mechanisms of the e-commerce platform improve the effect of EPA and exert online shopping purchase power in rural China. From a socio-technical perspective, this paper used adoption readiness of farmers and perceived risk to construct an integrated model to discern the effect of enhanced e-commerce institutional mechanisms on farmers' online shopping intention in the context of EPA.
Design/methodology/approach
The survey included 832 valid samples from rural farmers in Shanxi province. This study analyses using structural equation modelling (SEM) and bootstrap methods used to empirically test the model.
Findings
Findings suggest that enhanced e-commerce institutional mechanisms have significant direct and indirect positive impacts on farmers' online shopping intention; adoption readiness and perceived risk play partial mediation roles in determining the relationship between farmers' online shopping intention and enhanced e-commerce institutional mechanisms; and the indirect mediation effect of adoption readiness is greater than that of perceived risk.
Research limitations/implications
Although the proposed model was supported in the questionnaire survey, the investigation method was not completely excluded. Future research can combine the method of panel data and apply the framework to other e-commerce platforms, as well as to other cultural settings.
Practical implications
The study suggests that enhanced e-commerce institutional mechanisms that are based on the needs of farmers from poverty-stricken areas change the shopping habits of farmers. Moreover, enhanced e-commerce institutional mechanisms should allow farmers' perceived adoption readiness to play its promoting role and reduce the impeding role of perceived risk. The results of this study are conducive to the intensive implementation of the ‘Three Rural Issues’ strategy in China.
Originality/value
A new model to generate a two-factor mediation effect model by integrating the perceived effectiveness of enhanced e-commerce institutional mechanisms with farmers, farmers' adoption readiness, perceived risk and online shopping intention. The study explored the relationship between enhanced e-commerce institutional mechanisms and farmers' online shopping intention, bridging the gap in related empirical studies. Besides, this study first proposed farmers' adoption readiness and clarifies the mediating role of farmers' adoption readiness and perceived risk, which highlights the previously unnoticed role of farmers' adoption readiness.
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With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the…
Abstract
Purpose
With the analysis of the causes of corruption, this study aims to investigate specific anti-corruption measures that can be implemented to reform the political system and the social climate of China.
Design/methodology/approach
This study examines 97 severe corruption cases of high-ranking officials in China, which occurred between 2012 and 2015. As this insinuates that both institutional and social corruption are major problems in China, the analysis delves into multiple facts of corruption, including different types, four primary underlying causes, and suggestions regarding the implementation of three significant governmental shifts that focus on investigation, prevention tactics and legal regulations.
Findings
China’s corruption is not only individual-based but also it has developed into institutional corruption and social corruption. Besides human nature and instinct, the causes of corruption can be organised into four categories, namely, social customs, social transitions, institutional designs and institutional operations. For the removed high-ranking officials, the formation of interest chains was an important underlying cause behind their corruption.
Originality/value
This study makes a significant contribution to the literature because this study provides a well-rounded approach to a complex issue by highlighting the significance of democracy and the rule of law as ways to regulate human behaviour to combat future corruption.
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Haritz Gorostidi-Martinez, Weimin Xu and Xiaokang Zhao
As part of a cross-cultural research, the purpose of this paper is to provide further insights into the existing product-country image (PCI) of the Chinese consumers’ perceptions…
Abstract
Purpose
As part of a cross-cultural research, the purpose of this paper is to provide further insights into the existing product-country image (PCI) of the Chinese consumers’ perceptions of Spain, its products, and its people, thereby providing an overall contemporary Spanish PCI within the Chinese market.
Design/methodology/approach
In total, 215 valid structured questionnaires were gathered throughout China. Following a pre-investigation of 259 usable questionnaires, a 52-item construct was drawn from the existing widely used PCI item scales, designing a structured PCI construct, covering: “country image,” “personal image,” “product image,” “general knowledge about Spain,” and “personal data.”
Findings
The study provides: a PCI pre-investigation research results as well as a literature review on PCI topic; research results for the five hypotheses concerning Chinese citizens’ view of Spanish product price, quality, technicality, inventiveness, and known brands view; descriptive statistics as well as result graphs for each of the covered PCI sections; our PCI construct variable correlations with the tested five product image variables; and general implications.
Research limitations/implications
Standardizing PCI longitudinal studies, as well as focusing on how the Spanish Government and private sector should determine the long-term criteria to facilitate a clearer representation of the Spanish PCI evolution within the Chinese market, is advised.
Originality/value
The current study intends to capture insights for Spain and other country’s public and private sector decision makers to better integrate market and non-market strategies. The results would further assist delineating strategies to avoid the liability of foreignness of Spanish organizations within China.
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Mechanoreception is crucial for robotic planning and control applications, and for robotic fingers, mechanoreception is generally obtained through tactile sensors. As a new type…
Abstract
Purpose
Mechanoreception is crucial for robotic planning and control applications, and for robotic fingers, mechanoreception is generally obtained through tactile sensors. As a new type of robotic finger, the soft finger also requires mechanoreception, like contact force and object stiffness. Unlike rigid fingers, soft fingers have elastic structures, meaning there is a connection between force and deformation of the soft fingers. It allows soft fingers to achieve mechanoreception without using tactile sensors. This study aims to provide a mechanoreception sensing scheme of the soft finger without any tactile sensors.
Design/methodology/approach
This research uses bending sensors to measure the actual bending state under force and calculates the virtual bending state under assumed no-load conditions using pressure sensors and statics model. The difference between the virtual and actual finger states is the finger deformation under load, and its product with the finger stiffness can be used to calculate the contact force. There are distinctions between the virtual and actual finger state change rates in the pressing process. The difference caused by the stiffness of different objects is different, which can be used to identify the object stiffness.
Findings
Contact force perception can achieve a detection accuracy of 0.117 N root mean square error within the range of 0–6 N contact force. The contact object stiffness perception has a detection average deviation of about 15%, and the detection standard deviation is 10% for low-stiffness objects and 20% for high-stiffness objects. It performs better at detecting the stiffness of low-stiffness objects, which is consistent with the sensory ability of human fingers.
Originality/value
This paper proposes a universal mechanoreception method for soft fingers that only uses indispensable bending and pressure sensors without tactile sensors. It helps to reduce the hardware complexity of soft robots. Meanwhile, the soft finger no longer needs to deploy the tactile sensor at the fingertip, which can benefit the optimization design of the fingertip structure without considering the complex sensor installation. On the other hand, this approach is no longer confined to adding components needed. It can fully use the soft robot body’s physical elasticity to convert sensor signals. Essentially, It treats the soft actuators as soft sensors.