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Article
Publication date: 14 September 2015

Lin Ba, Zhenpeng He, Lingyan Guo, Young Chiang, Guichang Zhang and Xing Lu

The purpose of this paper is to improve the environment and save energy, friction reduction, lower oil consumption and emissions demand that are the chief objectives of the…

432

Abstract

Purpose

The purpose of this paper is to improve the environment and save energy, friction reduction, lower oil consumption and emissions demand that are the chief objectives of the automotive industry. The piston system is the largest frictional loss source, which accounts for about 40 per cent of the total frictional loss in engine. In this paper, the reciprocating tribometer, which is updated, was used to evaluate the friction and wear performances.

Design/methodology/approach

An alternate method is introduced to investigate the effect of reciprocating speed, normal load, oil pump speed and ring sample and oil temperature on friction coefficient with the ring/liner of a typical inline diesel engine. The orthogonal experiment is designed to identify the factors that dominate wear behavior. To understand the correlations between friction coefficients and wear well, different friction coefficient results were compared and explained by oil film build-up and asperity contact theory, such as the friction coefficient over a long period and averaged the friction coefficient over one revolution.

Findings

The friction coefficient changes little but fluctuates with a small amplitude in the stable stage. The sudden change of frequency, load and stroke will lead to the oil film rupture. The identification for the factors that dominates the wear loss is ranged as F (ring sample) > , E (oil sample) > , B (stroke) > , D (temperature) > , A (load) > , G (liner) > and C (frequency).

Originality/value

This paper develops and verifies a methodology capable of mimicking the real engine behavior at boundary and mixed lubrication regimes which can minimize frictional losses, wear, reduce much work for the experiment and reduce the cost. The originality of the work is well qualified, as very few papers on a similar analysis have been published, such as: The friction coefficient values fluctuating in the whole stage may be caused by the vibration of the system; suddenly, boundary alternation may help the oil film to form the lubrication; and weight loss mainly comes from the contribution of the friction coefficient value fluctuation. The paper also found that the statistics can gain more information from less experiment time based on a design of experiment.

Details

Industrial Lubrication and Tribology, vol. 67 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 9 December 2022

Hengyun Li, Lingyan Zhang, Rui (Ami) Guo, Haipeng Ji and Bruce X.B. Yu

This study aims to investigate the promoting effects of the quantity and quality of online review user-generated photos (UGPs) on perceived review usefulness. The research further…

1635

Abstract

Purpose

This study aims to investigate the promoting effects of the quantity and quality of online review user-generated photos (UGPs) on perceived review usefulness. The research further tests the hindering effect of human facial presence in review photos on review usefulness.

Design/methodology/approach

Based on review samples of restaurants in a tourist destination Las Vegas, this study used an integrated method combining a machine learning algorithm and econometric modeling.

Findings

Results indicate that the number of UGPs depicting a restaurant’s food, drink, menu and physical environment has positive impacts on perceived review usefulness. The quality of online review UGPs can also enhance perceived review usefulness, whereas facial presence in these UGPs hinders perceived review usefulness.

Practical implications

Findings suggest that practitioners can implement certain tactics to potentially improve consumers’ willingness to share more UGPs and UGPs with higher quality. Review websites could develop image-processing algorithms for identifying and presenting UGPs containing core attributes in prominent positions on the site.

Originality/value

To the best of the authors’ knowledge, this study is the first to present a comprehensive analytical framework investigating the enhancing or hindering roles of review photo quantity, photo quality and facial presence in online review UGPs on review usefulness. Using the heuristic-systematic model as a theoretical foundation, this study verifies the additivity effect and attenuation effect of UGPs’ visual elements on judgements of online review usefulness. Furthermore, it extends scalable image data analysis by adopting a deep transfer learning algorithm in hospitality and tourism.

Details

International Journal of Contemporary Hospitality Management, vol. 35 no. 7
Type: Research Article
ISSN: 0959-6119

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Article
Publication date: 4 December 2023

Feifei Zhong, Guoping Liu, Zhenyu Lu, Lingyan Hu, Yangyang Han, Yusong Xiao and Xinrui Zhang

Robotic arms’ interactions with the external environment are growing more intricate, demanding higher control precision. This study aims to enhance control precision by…

233

Abstract

Purpose

Robotic arms’ interactions with the external environment are growing more intricate, demanding higher control precision. This study aims to enhance control precision by establishing a dynamic model through the identification of the dynamic parameters of a self-designed robotic arm.

Design/methodology/approach

This study proposes an improved particle swarm optimization (IPSO) method for parameter identification, which comprehensively improves particle initialization diversity, dynamic adjustment of inertia weight, dynamic adjustment of local and global learning factors and global search capabilities. To reduce the number of particles and improve identification accuracy, a step-by-step dynamic parameter identification method was also proposed. Simultaneously, to fully unleash the dynamic characteristics of a robotic arm, and satisfy boundary conditions, a combination of high-order differentiable natural exponential functions and traditional Fourier series is used to develop an excitation trajectory. Finally, an arbitrary verification trajectory was planned using the IPSO to verify the accuracy of the dynamical parameter identification.

Findings

Experiments conducted on a self-designed robotic arm validate the proposed parameter identification method. By comparing it with IPSO1, IPSO2, IPSOd and least-square algorithms using the criteria of torque error and root mean square for each joint, the superiority of the IPSO algorithm in parameter identification becomes evident. In this case, the dynamic parameter results of each link are significantly improved.

Originality/value

A new parameter identification model was proposed and validated. Based on the experimental results, the stability of the identification results was improved, providing more accurate parameter identification for further applications.

Details

Industrial Robot: the international journal of robotics research and application, vol. 51 no. 1
Type: Research Article
ISSN: 0143-991X

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Article
Publication date: 1 September 2016

Xiaohui Yu, Fei Wang and Lina Wang

City wall is an important symbol of ancient Chinese cities with unique geographical and cultural characteristics. Thus, the preservation of this historic landmark is considered…

57

Abstract

City wall is an important symbol of ancient Chinese cities with unique geographical and cultural characteristics. Thus, the preservation of this historic landmark is considered significantly important. However, numerous residential construction activities and changes in ecological environment have destructed a great portion of the city walls in recent years. This study looks into the preservation of the ancient city walls from the systematic perspective and in line with the actual characteristics of Longdong Region to provide guideline measures for the protection and restoration of such landmark. Cognition and preservation are adopted extensively to investigate the specific situation of and the factors that influence the ancient city walls in this region. Preservation strategies for the city walls, including the “Axis-Point” system, planning control, and authenticity readability, are presented. The ancient city walls in Longdong Region can be preserved by protecting the entire region, the city, and the main wall body. The systematic method and preservation strategies at the “macro perspective,” “medium perspective” and “micro perspective” levels can solve the preservation problems of the ancient city walls in Longdong Region effectively.

Details

Open House International, vol. 41 no. 3
Type: Research Article
ISSN: 0168-2601

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Article
Publication date: 15 January 2025

Misal Ijaz, Farah Naz and Naila Sadiq

This research investigates the trajectory of Gulf region, focusing on the interplay between environmental, social and governance (ESG) factors and key elements – digital economy…

26

Abstract

Purpose

This research investigates the trajectory of Gulf region, focusing on the interplay between environmental, social and governance (ESG) factors and key elements – digital economy, green economy (GE), green finance, green energy and green innovation. This study aims to provide a nuanced understanding of how Gulf economies align their developmental pursuits with sustainability principles amidst the rapid evolution of digital technologies.

Design/methodology/approach

A data set of 95 listed companies from six Gulf Cooperation Council countries – Bahrain, Kuwait, Oman, Qatar, Saudi Arabia and the United Arab Emirates – from year 2016 to 2022 was compiled from reputable sources. Using fixed effect regression techniques, this study explores relationships, accounting for individual and time-specific variations.

Findings

This study indicates that key factors – digital economy, GE, green energy and green innovation – significantly influence ESG performance across Gulf nations underscoring the potential for strategic integration of these elements to enhance sustainable practices. However, the nonsignificant impact of green finance highlights a need for further exploration and refinement of financial mechanisms to effectively contribute to ESG goals in the Gulf region.

Research limitations/implications

The findings underscore the importance for Gulf policymakers to prioritize ongoing support and policy formulation fostering digitalization and green initiatives. Businesses in the region can enhance ESG performance by integrating sustainable practices, promoting long-term resilience and reputation. Investors and financial institutions can use these insights to guide investment decisions, prioritizing projects contributing to environmental sustainability and social responsibility.

Originality/value

Amidst the current sustainability imperative, this research holds unique value in its timely exploration of the Gulf region’s sustainable landscape, providing crucial insights into the interplay between ESG factors and digital and green initiatives.

Details

Journal of Science and Technology Policy Management, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2053-4620

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Article
Publication date: 9 June 2023

Shucai Yang, Shiwen Xing, Yang Yu, Pei Han, Chaoyang Guo and Lukai Liu

It was verified that the micro-texture in the front and back of the tool at the same time had a positive effect on improving the milling behavior and surface quality of the tool…

104

Abstract

Purpose

It was verified that the micro-texture in the front and back of the tool at the same time had a positive effect on improving the milling behavior and surface quality of the tool. The purpose of this study is to explore the rationality of simultaneous placement of micro-textures on the front and rear surfaces of ball-end milling cutters, analyze the influence of micro-texture parameters on tool milling behavior and workpiece surface quality, reveal its internal mechanism, and obtain the best micro-texture parameters by optimization.

Design/methodology/approach

First, the mechanism of micro-texture is studied based on the energy loss model. Second, the orthogonal experiment is designed to analyze the influence of micro-texture parameters on tool milling behavior and reveal its mechanism by combining simulation technology and cutting experiment. Finally, the parameters are optimized based on the artificial bee colony algorithm.

Findings

The results show that the simultaneous placement of micro-texture on the rake face and flank face of the tool has a positive effect on improving the milling behavior and surface quality of the tool. Taking milling force, tool wear and surface roughness as the evaluation criteria, the optimal parameter combination is obtained: the rake face micro-texture diameter is 50 µm, the distance from the micro-texture is 200 µm and the distance from the cutting edge is 110 µm; the diameter of the micro-textured flank is 40 µm, the distance from the micro-texture is 170 µm and the distance from the cutting edge is 130 µm.

Originality/value

Taking milling force, tool wear and surface roughness as the evaluation criteria, the optimal parameter combination is obtained: the rake face micro-texture diameter is 50 µm, the distance from the micro-texture is 200 µm and the distance from the cutting edge is 110 µm; the diameter of the micro-textured flank is 40 µm, the distance from the micro-texture is 170 µm and the distance from the cutting edge is 130 µm, which provides theoretical support for the further study of the micro-textured tool.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-01-2023-0022/

Details

Industrial Lubrication and Tribology, vol. 75 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

Available. Open Access. Open Access
Article
Publication date: 6 December 2022

Peiqing Li, Taiping Yang, Hao Zhang, Lijun Wang and Qipeng Li

This paper aimed a fractional-order sliding mode-based lateral lane-change control method that was proposed to improve the path-tracking accuracy of vehicle lateral motion.

599

Abstract

Purpose

This paper aimed a fractional-order sliding mode-based lateral lane-change control method that was proposed to improve the path-tracking accuracy of vehicle lateral motion.

Design/methodology/approach

In this paper the vehicle presighting and kinematic models were established, and a new sliding mode control isokinetic convergence law was devised based on the fractional order calculus to make the front wheel turning angle approach the desired value quickly. On this basis, a fractional gradient descent algorithm was proposed to adjust the radial basis function (RBF) neuron parameter update rules to improve the compensation speed of the neural network.

Findings

The simulation results revealed that, compared to the traditional sliding mode control strategy, the designed controller eliminated the jitter of the sliding mode control, sped up the response of the controller, reduced the overshoot of the system parameters and facilitated accurate and fast tracking of the desired path when the vehicle changed lanes at low speeds.

Originality/value

This paper combines the idea of fractional order calculus with gradient descent algorithm, proposed a fractional-order gradient descent method applied to RBF neural network and fast adjustment the position and width of neurons.

Details

Journal of Intelligent Manufacturing and Special Equipment, vol. 3 no. 2
Type: Research Article
ISSN: 2633-6596

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Article
Publication date: 26 November 2021

Liancheng Xiu, Zhiye Du, Yu Tian, Jingxuan He, Hongwei Cai and Fan Yi

The purpose of this paper is to develop a numerical simulation method based on the transient upstream finite element method (FEM) and Schottky emission theory to reveal the…

226

Abstract

Purpose

The purpose of this paper is to develop a numerical simulation method based on the transient upstream finite element method (FEM) and Schottky emission theory to reveal the distribution characteristics of space charge in oil-paper insulation.

Design/methodology/approach

The main insulation medium of the converter transformer in high voltage direct current transmission is oil-paper insulation. However, the influence of space charge is difficult to be fully considered in the insulation design and simulation of converter transformers. To reveal the influence characteristics of the space charge, this paper proposes a numerical simulation method based on Schottky emission theory and the transient upstream FEM. This method considers the influence of factors, such as carrier mobility, carrier recombination coefficient, trap capture coefficient and diffusion coefficient on the basis of multi-physics field coupling calculation of the electric field and fluid field.

Findings

A numerical simulation method considering multiple charge states is proposed for the space charge problem in oil-paper insulation. Meanwhile, a space charge measurement platform based on the electrostatic capacitance probe method for oil-paper insulation structure is built, and the effectiveness and accuracy of the numerical simulation method is verified.

Originality/value

A variety of models are calculated and analyzed by the numerical simulation method in this paper, and the distribution characteristics of the space charge and total electric field in oil-paper insulation medium with single-layer, polarity reversal of plate voltage and double-layer are obtained. The research results of this paper have the guiding significance for the engineering application of oil-paper insulation and the optimal design of converter transformer insulation.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 41 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 12 June 2019

Xing Yan and Yaping Chang

Microblog has become an important tool of social marketing since 2010. Compared with traditional blog, microblog has several distinctive features, such as ease of use, viral…

482

Abstract

Purpose

Microblog has become an important tool of social marketing since 2010. Compared with traditional blog, microblog has several distinctive features, such as ease of use, viral transmission, high interactivity and real-time communication. Microblog provides a communication platform for companies and consumers; however, it challenges companies’ consumer-brand relationship management. The purpose of this paper is to investigate the influencing mechanism of microblog interaction tactics on consumer-brand relationship.

Design/methodology/approach

Based on grounded theory, 66 representative companies’ posts on Weibo are collected, with 1,395 company posts and 5,959 following posts. An influence mechanism model of company microblog interaction tactics on consumer-brand relationship is proposed, then the saturation level of this mechanism is tested.

Findings

Results show that: first, companies adopt two types of tactics in microblog interaction: social interaction and task-oriented interaction; second, microblog interaction arises consumers’ emotional response and cognition toward specific brand and eventually influences consumer-brand relationship. Consumers’ emotional response includes pleasure and arousal, brand cognition includes perceived quality, perceived relatedness with companies and brand resonance; third, the influence mechanism differs among different consumer knowledge level, industry and brand awareness.

Practical implications

This study provides insight into the use of microblog interaction tactics. Companies may cross-use social interaction and task-oriented interaction tactics to enhance consumer-brand relationship. Companies need to produce microblog content based on the interests of consumers and further establish and improve fan feedback mechanism.

Originality/value

This paper constructs a model of the influence of company microblog interaction tactics on consumers. This study finds that co-creation activities initiated by companies are the new tactics to attract consumers on microblog. The finding adds new knowledge to the literature of company consumer interaction and provides a theoretical basis for the practice of microblog marketing.

Details

Journal of Contemporary Marketing Science, vol. 2 no. 1
Type: Research Article
ISSN: 2516-7480

Keywords

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