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Article
Publication date: 27 June 2019

Chi Zhang, Pu Xue and Yubo Luo

Strain sensors have been widely used to measure the strain of the structure. However, the ordinary sensing elements are not suitable for measuring large deformation on an…

Abstract

Purpose

Strain sensors have been widely used to measure the strain of the structure. However, the ordinary sensing elements are not suitable for measuring large deformation on an irregular surface, which limits their applications. Recently, flexible sensors have attracted extensive interest because they can overcome the shortage of the ordinary sensing elements. The paper aims to discuss this issue.

Design/methodology/approach

In this paper, the whole measurement process of strain sensing behavior and the dimension design of fle3xible strain sensing system use the macroscopic measurement method of material tensile test to accurately measure the resistance change with strain. Afterwards, combining electrical components, the flexible strain sensors are produced for two biomedical applications: the wearable data-collecting gloves and rehabilitation training system.

Findings

The results show that the developed conductive fabric can exhibit high sensitivity, large workable strain range (>50 percent) under simple and repeated tension and good stability. Both applications demonstrate that the polypyrrole-coated fabric sensor can successfully measure the large and repeat strain, capture the motion of body and display corresponding information almost in real time.

Originality/value

The limitation lies in the lack of a holistic strain sensing mechanism study, and the lack of a corresponding theoretical model to explain the experimental results.

Details

International Journal of Clothing Science and Technology, vol. 31 no. 5
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 8 June 2021

Eryong Liu, Yuan Xue, Yaping Bai, Jibin Pu, Shuangming Du and Huiling Du

The purpose of this paper is to improve the tribological properties of aluminum cylinder liner. Higher martensite contents were closely related to the higher hardness and…

Abstract

Purpose

The purpose of this paper is to improve the tribological properties of aluminum cylinder liner. Higher martensite contents were closely related to the higher hardness and excellent wear resistance of Fe-based coatings. Furthermore, the grain size of the Fe-based coating was approximately 40 nm, which provides an excellent fine grain strengthening effect.

Design/methodology/approach

To improve the tribological properties of aluminum cylinder liners, a Fe-based martensite coating was prepared by internal plasma spraying technology, whose microstructure and tribological properties were then investigated.

Findings

Sprayed Fe-based coating possessed a low contact angle and strong adhesion with lubricating oil. In a simulated engine condition, Fe-based coating exhibited a decreased friction coefficient and increased wear resistance under oil lubrication, which was dominated by a stronger adhesive force with lubricating oil, higher martensite contents on the worn surface, higher hardness and higher H/E value than those of the reference HT 200 and Al-19Si cylinder material.

Originality/value

Nanostructure Fe-based martensite coating was sprayed on an aluminum cylinder liner, which demonstrated remarkable advantages over the reference cylinder material.

Details

Industrial Lubrication and Tribology, vol. 73 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 4 November 2014

ShiYang Zhao and Pu Xue

– The purpose of the paper is to improve the calculability of a continuum damage failure model of composite laminates based on Tsai-Wu criteria.

Abstract

Purpose

The purpose of the paper is to improve the calculability of a continuum damage failure model of composite laminates based on Tsai-Wu criteria.

Design/methodology/approach

A technique based on viscous regularization, a characteristic element length and fracture energies of fiber and matrix are used in the model.

Findings

The calculability of the material model is improved. The modified model can predict the behavior of composite structure better.

Originality/value

The convergence problem and the mesh softening problem are main concern in the calculability of numerical model. In order to improve the convergence, a technique based on viscous regularization of damage variable is used. Meanwhile, characteristic element length and fracture energies of fiber and matrix are added into the damage constitutive equation to reduce the mesh sensitivity of numerical results. Finally, a laminated structure with damages is implemented using a User Material Subroutine in ABAQUS/Standard. Mesh sensitivity and value of viscosity are discussed.

Details

Multidiscipline Modeling in Materials and Structures, vol. 10 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 10 June 2022

Minjuan Zhang, Ning Jing, Zhen Liu, Chunyang Li and Ning Zhang

An interferogram is produced by modulating the difference between the extraordinary refractive index and the ordinary refractive index for photoelastic crystals in…

Abstract

Purpose

An interferogram is produced by modulating the difference between the extraordinary refractive index and the ordinary refractive index for photoelastic crystals in photoelastic-modulated Fourier transform spectrometers (PEM-FTs). Due to the influence of the refractive index dispersion characteristics on the maximum optical path difference of the interferogram, it is necessary to study wavelength calibration methods.

Design/methodology/approach

A wavelength calibration method for PEM-FTs was proposed based on the modulation principle of the photoelastic-modulated interferometer and the relationship between the maximum optical path difference and the refractive index difference. A 632.8 nm narrow-pulse laser was used as a reference source to measure the maximum optical path difference () of the interferogram, and the parameter was used to calculate the discrete frequency points in the frequency domain. To account for the influence of refractive index dispersion on the maximum optical path difference, the refractive index curve for the photoelastic crystal was used to adjust the discrete frequency coordinates.

Findings

The error in the reconstructed spectral frequency coordinates clearly decreased. The maximum relative error was 2.5%. A good solar absorption spectrum was obtained with a PEM-FT experimental platform and the wavelength calibration method.

Originality/value

The interferogram is produced by adjusting the difference between extraordinary refractive index and ordinary refractive index for the photoelastic crystal in the PEM-FTs. Given the wavelength dependence on the refractive indices, in view of the modulation principle of the photoelastic modulated interferometer, the relationship between the maximum optical path difference and the refractive index difference, the variation law of the refractive index of the photoelastic crystal and the process of spectral reconstruction is presented in this paper.

Details

Sensor Review, vol. 42 no. 4
Type: Research Article
ISSN: 0260-2288

Keywords

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

Article
Publication date: 2 October 2019

Simona Alfiero, Michael Christofi and Alessandro Bonadonna

The purpose of this paper is to demonstrate how food waste management can affect both retail and distribution operators’ efficiency performance and their ability to create…

Abstract

Purpose

The purpose of this paper is to demonstrate how food waste management can affect both retail and distribution operators’ efficiency performance and their ability to create value. In particular, the paper shows how optimizing food waste management characterizes best practices and favors the development of sustainability.

Design/methodology/approach

Based on a survey of 196 outdoor market operators (including farmers and street food traders) from 27 outdoor markets, the authors analyzed unsold food/food wastage processes vis-à-vis the operators’ behavior and attitude. To provide accurate definitions of the satisfaction levels, a consumer perception survey was carried out, with a usable sample of 2,107 questionnaires. The efficiency performance was evaluated according to data envelopment analysis.

Findings

The results showed that farmers operate more efficiently than street food traders and that the traditional management of unsold food/food waste is an important competitive element in this sector.

Research limitations/implications

The sample represents the Greater Turin Area in Italy, i.e., thus, limiting generalizability of the results. In addition, the variables analyzed were limited to certain aspects of selling processes and food waste management.

Practical implications

The results provide some indicators on how a more rational style of unsold food management can improve an operators’ performance and help make a social impact.

Originality/value

To the best of the authors’ knowledge, this is the first study that analyses outdoor market operators’ efficiency, based on the use of food waste as a variable affecting their performance.

Details

British Food Journal, vol. 122 no. 5
Type: Research Article
ISSN: 0007-070X

Keywords

Article
Publication date: 1 December 2004

George K. Stylios

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…

3008

Abstract

Examines the tenth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 16 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 1 December 2003

George K. Stylios

Examines the ninth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects…

1152

Abstract

Examines the ninth published year of the ITCRR. Runs the whole gamut of textile innovation, research and testing, some of which investigates hitherto untouched aspects. Subjects discussed include cotton fabric processing, asbestos substitutes, textile adjuncts to cardiovascular surgery, wet textile processes, hand evaluation, nanotechnology, thermoplastic composites, robotic ironing, protective clothing (agricultural and industrial), ecological aspects of fibre properties – to name but a few! There would appear to be no limit to the future potential for textile applications.

Details

International Journal of Clothing Science and Technology, vol. 15 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

Article
Publication date: 20 June 2008

Hua Wu, X.Q. Zeng and T.H. Ren

The paper's aim is to study tribological performances of two 2‐mercaptobenzothiazole derivatives which are ashless and lacking in phosphorous as lubricating oil additives…

Abstract

Purpose

The paper's aim is to study tribological performances of two 2‐mercaptobenzothiazole derivatives which are ashless and lacking in phosphorous as lubricating oil additives in HVIW H150 base oils.

Design/methodology/approach

The two 2‐mercaptobenzothiazole derivatives were synthesized; their tribological performances were evaluated with a four‐ball machine, and the worn surface was analyzed with a X‐ray photoelectron spectroscopy (XPS).

Findings

The two compounds possess good anti‐wear properties and excellent load‐carrying capacity. According to the XPS results, the additive reacted with counter‐face metal and generated a sulphur‐containing inorganic film consisting of FeS, FeS2 and FeSO4, and a complex N‐containing resin polymer film.

Research limitations/implications

Their antioxidant properties are not estimated, and their anti‐wear action mechanism need to be further explored.

Practical implications

Two useful ashless AW lubricating oil additives were synthesized, and may be has potential as gas engine lubricating oil additives.

Originality/value

This paper provides a study of some N, S‐containing heterocyclic compounds as lubricating oil additives.

Details

Industrial Lubrication and Tribology, vol. 60 no. 4
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 31 May 2022

Yung-Ming Cheng

The purpose of this study is to propose the research model integrating the expectation-confirmation model with the views of learning engagement (LE) and extending DeLone…

Abstract

Purpose

The purpose of this study is to propose the research model integrating the expectation-confirmation model with the views of learning engagement (LE) and extending DeLone and McLean information systems (IS) success model to examine whether quality determinants as antecedents to students' beliefs can influence students' continuance intention of massive open online courses (MOOCs).

Design/methodology/approach

Sample data for this study were collected from students enrolled in a comprehensive university in Taiwan. A total of 600 questionnaires were distributed, and 363 (60.5%) useable questionnaires were analyzed using structural equation modeling in this study.

Findings

This study proved that students' perceived knowledge quality, system quality, interface design quality, learner–instructor interaction quality, and collaboration quality all positively caused students' perceived usefulness, confirmation and LE in MOOCs, which jointly explained students' satisfaction with MOOCs and subsequently resulted in students' continuance intention of MOOCs.

Originality/value

This study fully evaluates IS-related and interaction-related quality determinants via an understanding of students' state of LE in explaining students' continuance intention of MOOCs that is difficult to expound with only their utilitarian perception of MOOCs. Hence, this study contributes to deep insights into an all-round quality evaluation in the field of MOOCs continuance intention and takes extrinsic and intrinsic motivators into account in the theoretical development of MOOCs continuance intention to acquire a more comprehensive and robust analysis.

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