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Article
Publication date: 10 November 2023

Yong Gui and Lanxin Zhang

Influenced by the constantly changing manufacturing environment, no single dispatching rule (SDR) can consistently obtain better scheduling results than other rules for the…

Abstract

Purpose

Influenced by the constantly changing manufacturing environment, no single dispatching rule (SDR) can consistently obtain better scheduling results than other rules for the dynamic job-shop scheduling problem (DJSP). Although the dynamic SDR selection classifier (DSSC) mined by traditional data-mining-based scheduling method has shown some improvement in comparison to an SDR, the enhancement is not significant since the rule selected by DSSC is still an SDR.

Design/methodology/approach

This paper presents a novel data-mining-based scheduling method for the DJSP with machine failure aiming at minimizing the makespan. Firstly, a scheduling priority relation model (SPRM) is constructed to determine the appropriate priority relation between two operations based on the production system state and the difference between their priority values calculated using multiple SDRs. Subsequently, a training sample acquisition mechanism based on the optimal scheduling schemes is proposed to acquire training samples for the SPRM. Furthermore, feature selection and machine learning are conducted using the genetic algorithm and extreme learning machine to mine the SPRM.

Findings

Results from numerical experiments demonstrate that the SPRM, mined by the proposed method, not only achieves better scheduling results in most manufacturing environments but also maintains a higher level of stability in diverse manufacturing environments than an SDR and the DSSC.

Originality/value

This paper constructs a SPRM and mines it based on data mining technologies to obtain better results than an SDR and the DSSC in various manufacturing environments.

Details

Kybernetes, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 November 2021

Ruipeng Tong, Lulu Wang, Lanxin Cao, Boling Zhang and Xiaoyi Yang

Psychosocial factors have received increasing attention regarding significantly influencing safety in the construction industry. This research attempts to comprehensively…

1024

Abstract

Purpose

Psychosocial factors have received increasing attention regarding significantly influencing safety in the construction industry. This research attempts to comprehensively summarize psychosocial factors related to safety performance of construction workers. In the context of coronavirus disease 2019, some typical psychosocial factors are selected to further analyze their influence mechanism of safety performance.

Design/methodology/approach

First, a literature review process was conducted to identify and summarize relevant psychosocial factors. Then, considering the impact of the epidemic, hypotheses on the relationship between six selected psychosocial factors (i.e. work stress, role ambiguity, work–family conflict, autonomy, social support and interpersonal conflict) and safety performance were proposed, and a hypothetical model was developed based on job demands-resources theory. Finally, a meta-analysis was used to examine these hypotheses and the model.

Findings

The results showed these psychosocial factors indirectly influenced workers’ safety performance by impacting on their occupational psychology condition (i.e. burnout and engagement). Work stress, role ambiguity, work–family conflict and interpersonal conflict were negatively related to safety performance by promoting burnout and affecting engagement. Autonomy and social support were positively related to safety performance by improving work engagement and reducing burnout.

Originality/value

This research is the pioneer systematically describing the overall picture of psychosocial factors related to the safety performance of construction workers. Through deeply discussed the mechanism of psychosocial factors and safety performance, it could provide a reference for the theory and application of psychosocial factors in the field of construction safety management.

Details

Engineering, Construction and Architectural Management, vol. 30 no. 2
Type: Research Article
ISSN: 0969-9988

Keywords

Article
Publication date: 27 May 2020

Yingwei Liu, Tao Wang, Ling Zhou and Chunyan Nie

The essence of “Chinese element” has been pinpointed as the representation of national cultural archetype resource of China, which reflects to the overall power enhancement of…

Abstract

Purpose

The essence of “Chinese element” has been pinpointed as the representation of national cultural archetype resource of China, which reflects to the overall power enhancement of China. Applying the Chinese national cultural archetype resource, which will be used for promoting the Chinese Brand internationalization, aims for the consumers' approval with the hope of integrating and spreading the unique cultural advantage of Chinese brand. The recognizing of Chinese brand's cultural archetype in this paper has constituted the basis of Chinese brand's cultural archetype strategy.

Design/methodology/approach

Based on the Grounded Theory, this paper has collected and analyzed the value symbols, character images and theme stories of Chinese narrative advertisements and constructed the cultural archetype framework of Chinese brands. This paper makes a comprehensive application of Charmaz's constructivist analysis and the main axis analysis and inspection method advocated by Strauss, with the aim of building a more objective and systematic theoretical framework for the Chinese brand cultural archetype.

Findings

In this framework, it revealed: (1) Chinese brand's cultural archetype can be divided into 12 concrete archetypes according to individual's relationship with self, the other, community and nature; (2) Consumers' different ways of self-categorization are attributed as the essential difference among various archetypes. This paper also compared and analyzed the differences between Chinese and Western cultural archetypes from three perspectives, formation of social structure, pedigree of myth and character's feature.

Originality/value

This paper has certain innovative significance to the theoretical construction of the archetype of Chinese brand culture. First, based on the cultural perspective, this paper applied the cultural psychological connotation of archetype to the brand research across culture, which is more conducive to the researchers' investigation of the cultural psychology of consumers in the cross-cultural context? Second, based on the identification and comparative study of Chinese brand culture archetype, it provides a new expansion and supplement for the research on brand internationalization and globalization in emerging countries.

Details

Journal of Contemporary Marketing Science, vol. 3 no. 1
Type: Research Article
ISSN: 2516-7480

Keywords

Article
Publication date: 2 November 2015

Lizhu Liu, Hong Zhang, Nan Zhang and Ling Weng

The purpose of this study is to investigate the effects of two epoxy ratio and carboxyl-terminated butadiene solid rubber (CTBN) content on adhesive and flexible copper clad…

Abstract

Purpose

The purpose of this study is to investigate the effects of two epoxy ratio and carboxyl-terminated butadiene solid rubber (CTBN) content on adhesive and flexible copper clad laminate (FCCL) performance. The epoxy adhesive used for FCCL was prepared with epoxy resin of 901 and 6128 as matrix and CTBN as toughener.

Design/methodology/approach

The epoxy adhesive was prepared with epoxy resin as matrix, CTBN as toughener and 4,4′-diamino diphenyl sulfone as curing agent in solvent of butanone by mechanical agitation. The adhesives were cast on the polyimide film; subsequently, the polyimide film was dried at 160°C for 3 min to remove the solvent. Then, it was laminated with copper foil at 180°C with the pressure of 12 MPa for 3 min. The FCCL was obtained after heating for 3 h in a vacuum oven at 160°C. The structure and dielectric properties of cured adhesive, surface morphology of peeling FCCL and mechanical properties of FCCL were determined.

Findings

CTBN was found to react with the epoxy resin during the curing process, with the rubber phase being precipitated and dispersed in the epoxy matrix. The relative dielectric constant and the dielectric loss tangent slightly increased with increasing CTBN content. The peeling strength of FCCL increased accompanied by a decrease of folding resistance with the increase of 901 content. Further, with the addition of XNBR, the peel strength of FCCL increased, as well as the folding resistance of FCCL, but at a higher XNBR level of 20 weight per cent, the folding resistance of FCCL tended to decrease.

Research limitations/implications

In the study reported here, the effects of different epoxy resin molecular weight and CTBN content were investigated. Results of this research could benefit in-depth understanding of the influence of epoxy resin molecular weight and CTBN content on adhesive performance and could further promote the development of epoxy adhesive.

Practical implications

The adhesion of epoxy adhesive prepared from epoxy resin with different molecular weight and CTBN increased, leading to the increase in peeling strength and folding resistance of FCCL.

Social implications

The peeling strength of FCCL increased as the adhesion strength of epoxy adhesive increased by adding CTBN, making FCCL widely applicable.

Originality/value

The mechanical properties of epoxy adhesive were increased by adding CTBN. The effects of CTBN on the microstructure and properties of FCCL were discussed in detail.

Details

Pigment & Resin Technology, vol. 44 no. 6
Type: Research Article
ISSN: 0369-9420

Keywords

Article
Publication date: 1 September 2017

Yufang Jin and Xiangjian Zhang

With the continuous expansion of urban scale, blindly increasing or controlling transportation infrastructure possibly creates a short board in an urban system. In this study, a…

Abstract

With the continuous expansion of urban scale, blindly increasing or controlling transportation infrastructure possibly creates a short board in an urban system. In this study, a macro traffic integrated system was constructed according to a city's economic size distribution and transportation infrastructure. The planning strategy of traffic, industry, space interaction and coordinated development was put forward. Through theoretical model, the evolution mechanism between transportation infrastructure and economic scale distribution was revealed. Starting from the center of the city and inter city level, China's new urbanization strategy was implemented, and a comprehensive transportation system model was built. The traffic planning in Singapore was taken as an example, and the solution to traffic problems such as congestion, traffic jam, and distance was obtained. Practice has proved that the rational and effective urban transportation infrastructure construction can effectively promote the coordinated development of economy and resources, and comprehensively enhance the level of integrated transport services.

Details

Open House International, vol. 42 no. 3
Type: Research Article
ISSN: 0168-2601

Keywords

Article
Publication date: 3 August 2021

Yong-Hua Li, Yang Cao, Yong-Xin Wu, Xiao-Ning Bai and Jia-Wei Mao

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size…

Abstract

Purpose

This paper aims to establish the relationship between crosswind speed and pantograph-catenary lateral deviation, as well as quantify the influence of crosswind speed and rod size uncertainty on pantograph-catenary contact reliability.

Design/methodology/approach

The closed vector method is used to establish the pantograph-catenary kinematics formula. A new prediction model is proposed by using the bird swarm algorithm to optimize the grey model. The lateral deviation of the pantograph and catenary is predicted via the new model. Then the relationship between the effective length of the rod and operating mileage is inferred by combining the effective length theory with the Gamma process, as well as the pantograph-catenary contact reliability model is established according to reliability theory.

Findings

The results obtained show the impacts of uncertainty design parameters of pantograph rods on pantograph-catenary contact reliability index, and the results at crosswind speed of 0 ms−1 and 5 ms−1 are 5.0630 and 4.1442, respectively. The reliability decreases with the increasing crosswind speed, and can be greater than the reliability calculated for rod size degradation due to long-term use.

Originality/value

Most preceding works on pantograph-catenary contact reliability were based on principles of dynamics, without considering the pantograph-catenary relative motion. This research reveals the law of pantograph-catenary relative motion for uncertainty design parameters and crosswind, and quantifies the reliability from the angle of kinematics.

Details

International Journal of Structural Integrity, vol. 12 no. 4
Type: Research Article
ISSN: 1757-9864

Keywords

Article
Publication date: 10 August 2022

Weichao Yang, Yikang Liu, E. Deng, Youwu Wang, Xuhui He, Mingfeng Lei and Yunfeng Zou

The purpose of this paper is to understand the natural wind field characteristics of the tunnel entrance section and analyzing the aerodynamic performance of high-speed railway…

Abstract

Purpose

The purpose of this paper is to understand the natural wind field characteristics of the tunnel entrance section and analyzing the aerodynamic performance of high-speed railway trains (HSRTs) under natural winds.

Design/methodology/approach

Three typical tunnel entrance section sites, namely, tunnel–bridge in a dry canyon (TBDC), tunnel–bridge in a river canyon (TBRC) and tunnel–flat ground (TF), are selected to conduct a continuous wind field measurement. Based on the measured wind characteristics, the natural winds of the TBDC and TF sites are reconstituted and imported into the two corresponding full-scale computational fluid dynamics models. The aerodynamic loads of the HSRT running on TBDC and TF with reconstituted winds are simply analyzed.

Findings

The von Kármán spectrum can be used to describe the wind field at the tunnel entrance section. In the reconstituted natural wind condition, a time-varying feature of wind speed distribution and leeward side vortex around the HSRT caused by the wind speed fluctuation is found. The fluctuating amplitude of aerodynamic loads at the TBDC infrastructure is up to 97.9% larger than that at the TF infrastructure.

Originality/value

The natural wind characteristics at tunnel entrance sections on the high-speed railway are first measured and analyzed. A numerical reconstitution scheme considering the temporal and spatial variation of natural wind speed is proposed and verified based on field measurement results. The aerodynamic performance of an HSRT under reconstituted natural winds is first investigated.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 2
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 6 August 2019

Ab Kasaeian, Reza Daneshazarian, Fathollah Pourfayaz, Sahar Babaei, Mojgan Sheikhpour and Shima Nakhjavani

Because of its increased absorptance in fluid and reduced heat loss, direct absorption nanofluid (DANF) is receiving intense interest as an efficient way to harvest solar energy…

Abstract

Purpose

Because of its increased absorptance in fluid and reduced heat loss, direct absorption nanofluid (DANF) is receiving intense interest as an efficient way to harvest solar energy. This work aims to investigate, for the first time, the application of DANF in parabolic trough collectors (PTC), a promising collector for solar thermal systems.

Design/methodology/approach

A representative flow and heat transfer study of different fluids in a straight tube is conducted, and the basic energy equation and radiative transfer equations are numerically solved to obtain the fluid temperature distribution and energy conversion efficiency. Ethylene glycol (EG) and different concentrations of (i.e., 0.1-0.6 per cent) multi-wall carbon nanotubes (MWCNT) in EG are used as sample fluids. Four cases are studied for a traditional PTC (i.e., using metal tube) and a direct absorption PTC (i.e., using transparent tube) including a bare tube, a tube with an air-filled glass envelope and a tube with vacuumed glass envelop. The numerical results are verified by an experimental study using a copper-glass absorber tube, which reveals the good potential of DANFs.

Findings

Compared with a conventional PTC, using DANF shows an increase of 8.6 per cent and 6.5 K, respectively, in thermal efficiency and outlet temperature difference at a volume fraction (0.5 per cent) of nanoparticles. The results also show that the improvement in solar efficiency increases with increasing particle concentrations, and the vacuum insulated case has the highest efficiency.

Originality/value

In all previous studies, an important section was missing as the effect of photons on the direct solar absorption trough collector, which is considered in this study. This paper proposes a new concept of using direct solar absorption nanofluids for concentrated solar collectors and analyzes the performance of both absorptance and transmittance efficiency considerations. To reveal the potential of the new concept, an analytical model based on energy balance is developed, and two case studies are performed.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 30 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

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