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Article
Publication date: 18 June 2024

Jingjing Zhao, Yuan Li, Liang Xie and Jinxiang Liu

This study aims to propose an optimization framework using deep neural networks (DNN) coupled with nondominated sorting genetic algorithm II and technique for order preference by…

67

Abstract

Purpose

This study aims to propose an optimization framework using deep neural networks (DNN) coupled with nondominated sorting genetic algorithm II and technique for order preference by similarity to an ideal solution method to improve the tribological properties of camshaft bearing pairs of internal combustion engine.

Design/methodology/approach

A lubrication model based on the theory of elastohydrodynamic lubrication and flexible multibody dynamics was developed for a V6 diesel engine. Setting DNN model as fitness function, the multi-objective optimization genetic algorithm and decision-making method were used to optimize the bearing pair structure with the goal of minimizing the total friction loss and the difference of the average values of minimum oil film thickness.

Findings

The results show that the lubrication state corresponding to the optimized bearing pair structure is elastohydrodynamic lubrication. Compared with the original structure, the optimized structure significantly reduces the total friction loss.

Originality/value

The optimized performance and corresponding structural parameters are obtained, and the optimization results were verified through multibody dynamics simulation.

Peer review

The peer review history for this article is available at: https://publons.com/publon/10.1108/ILT-12-2023-0417/

Details

Industrial Lubrication and Tribology, vol. 76 no. 5
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 23 December 2015

Shenjun Qin and Shenyong Li

55

Abstract

Details

World Journal of Engineering, vol. 12 no. 6
Type: Research Article
ISSN: 1708-5284

Available. Content available
Book part
Publication date: 6 June 2016

Jingjing Yang, Chris Ryan and Lingyun Zhang

Abstract

Details

Social Conflict and Harmony: Tourism in China’s Multi-Ethnic Communities
Type: Book
ISBN: 978-1-78441-356-9

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Article
Publication date: 3 May 2016

Hong Men, Bin Sun, Xiao Zhao, Xiujie Li, Jingjing Liu and Zhiming Xu

The purpose of this study is to analyze the corrosion behavior of 304SS in three kinds of solution, 3.5 per cent NaCl, 5 per cent H2SO4 and 1 M (1 mol/L) NaOH, using…

199

Abstract

Purpose

The purpose of this study is to analyze the corrosion behavior of 304SS in three kinds of solution, 3.5 per cent NaCl, 5 per cent H2SO4 and 1 M (1 mol/L) NaOH, using electrochemical noise.

Design/methodology/approach

Corrosion types and rates were characterized by spectrum and time-domain analysis. EN signals were evaluated using a novel method of phase space reconstruction and chaos theory. To evaluate the chaotic characteristics of corrosion systems, the delay time was obtained by the mutual information method and the embedding dimension was obtained by the average false neighbors method.

Findings

The varying degrees of chaos in the corrosion systems were indicated by positive largest Lyapunov exponents of the electrochemical potential noise.

Originality/value

The change of correlation dimension in three kinds of solution demonstrated significant differences, clearly differentiating various types of corrosion.

Details

Anti-Corrosion Methods and Materials, vol. 63 no. 3
Type: Research Article
ISSN: 0003-5599

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Article
Publication date: 30 August 2022

Yan Zhang, Xianghu Ge, Xin Zhao, Xiaorui Yang, Shanghe Liu and Jingjing Xuan

The purpose of this paper is to research the induced flashover laws of different insulation materials under electrostatic electromagnetic pulse, and the induced flashover…

466

Abstract

Purpose

The purpose of this paper is to research the induced flashover laws of different insulation materials under electrostatic electromagnetic pulse, and the induced flashover characteristics of different electrode structures are further explored.

Design/methodology/approach

According to standard IEC 61000–4-2, an experimental system of electrostatic electromagnetic pulse flashover for insulation materials is established. The induction flashover laws of polytetrafluoroethylene, epoxy resin and polymethyl methacrylate surface-mounted finger electrodes under the different intensity of electrostatic electromagnetic pulse are researched. The influence of the finger electrode, needle–needle electrode and needle–plate electrode on insulation flashover was compared. Secondary electron emission avalanche (SEEA) and field superposition theory are used to analyze the experimental results of electrostatic electromagnetic pulse induced flashover.

Findings

The larger the dielectric strength of insulation materials, the more difficult flashover occurs on the surface. The field superposition enhances collision ionization between electrons and gas molecules, which leads to the insulation materials surface induced flashover easily by electrostatic electromagnetic pulse. The sharper the electrode shapes on the insulation materials surface, the stronger the electric field intensity at the cathode triple junction, more initial electrons are excited to form the discharge channel, which easily leads to flashover on the surface of the insulating material.

Originality/value

The proposed field superposition combined with the SEEA method provides a new study perspective and enables a more rational, comprehensive analysis of electrostatic electromagnetic pulse induced flashover of insulation materials. The work of this paper can provide a reference for the safety protection of spacecraft in orbit under a strong electromagnetic field environment, increase the service life of spacecraft and improve the reliability of spacecraft’s safe operation in orbit. It provides a basis for the selection of insulation materials for equipment under the different intensities of the external electromagnetic environment.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering , vol. 42 no. 1
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 12 November 2013

Jinxi Wang, Pei Ling, Jingjing Yang and Jing Zhao

A total of 283 coal and parting samples were taken from the Pingshuo mine district, Ningwu coalfield, China. The contents, distribution and enrichment mechanism of 12 hazardous…

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Abstract

A total of 283 coal and parting samples were taken from the Pingshuo mine district, Ningwu coalfield, China. The contents, distribution and enrichment mechanism of 12 hazardous trace elements were studied. The results indicate that Co, Ni, Zn, Cu, Ag and Cr have the chalcophile affinity; Ba, Cd, U are related with clay mineral; Mn is mainly related with carbonate minerals; Pb and Be may be related with sulfide, clay mineral and organic matter. Most of trace elements were associated with terrigenous clastic and clay. The elements (Cr, Pb, Be, Ag, Cu, U, Cd) were enriched in the wet forest and low swamps.

Details

World Journal of Engineering, vol. 10 no. 5
Type: Research Article
ISSN: 1708-5284

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Abstract

Graphical abstract

Purpose

The theme park industry has attracted wide attention and visitors’ perceptions are key to improving theme park management. Applying the cognitive-affective theory, this study aims to explore various cognitive attributes and affective attitudes and how they affect the overall theme park image.

Design/methodology/approach

A mixed research method was used to analyze tourists’ cognitive, affective and overall evaluations of theme parks through text mining and logistic regression and to verify their internal relationships.

Findings

Study 1 confirms the impact of six features of theme parks, including food and beverage consumption, merchandising, spatiality, immersive technologies, interactive performances and thematization. Study 2 reveals that finer-grained emotions such as goodness, sadness, disgust, surprise, fear, joy and anger are present in visitor reviews. Study 3 confirms the significant influence of cognitive characteristics and emotions related to theme parks on the overall image through regression analysis. The findings carry meaningful implications for theme park managers, offering guidance on customer needs, perceived negative attributes and how to improve visitor experiences.

Originality/value

This study explores the attribute characteristics of cognitive and affective images of theme parks and their influence on the overall image, thereby enriching the research on the connotations of cognitive-affective theory. In particular, this study introduces and quantitatively analyses the concept of theme parks for the first time through a large-scale data analysis, which empirically reconciles the contradictions of previous reviews of different definitions of theme parks.

图形摘要

主题公园评论:文本挖掘的认知特征和情感如何决定主题公园形象

摘要

目的

主题公园行业备受关注, 而游客的看法是改进主题公园管理的关键所在。本研究运用认知-情感理论, 旨在探索游客评论的认知属性与情感态度, 以及它们如何影响主题公园的整体形象。

设计/方法/途径

采用混合研究方法, 通过文本挖掘和逻辑回归分析游客对主题公园的认知、情感及总体评价, 并验证它们之间的内在关系。

发现

研究1证实了主题公园的六个特征所产生的影响, 包括餐饮消费、商品销售、空间性、沉浸式技术、互动表演和主题化。研究2表明, 游客评价中存在更细化的情感, 如好感、悲伤、厌恶、惊讶、恐惧、喜悦和愤怒。研究3通过回归分析证实了与主题公园相关的认知和情感特征对整体形象具有显著影响。这些研究结果对主题公园管理者具有重要意义, 为了解客户需求、识别负面属性以及如何改善游客体验提供了指导。

原创性

本研究对主题公园认知和情感形象的属性特征及其对整体形象的影响进行了探索, 从而丰富了认知-情感理论内涵。特别是本研究首次通过引入大规模数据并量化分析了主题公园的概念, 从实证角度调和了以往针对主题公园不同定义的相关评论中存在的矛盾。

Resumen gráfico

Reseñas de parques temáticos: cómo la minería de textos de las características cognitivas y las emociones pueden determinar la imagen del parque temático

Resumen

Propósito

El sector de los parques temáticos ha atraído una gran atención y las percepciones de los visitantes son clave para mejorar su gestión. Aplicando la teoría cognitivo-afectiva, este estudio pretende explorar diversos atributos cognitivos y actitudes afectivas, y cómo afectan a la imagen global del parque temático.

Diseño/metodología/enfoque

Se adoptó un enfoque de investigación de métodos mixtos para analizar las evaluaciones cognitivas, afectivas y globales de los turistas sobre los parques temáticos mediante minería de textos y regresión logística, y para validar la relación intrínseca entre ellas.

Conclusiones

El estudio 1 confirmó el impacto de seis características de los parques temáticos, como el consumo de alimentos y bebidas, el merchandising, la espacialidad, las tecnologías inmersivas, los espectáculos interactivos y la tematización. El estudio 2 reveló la presencia de emociones más sutiles en las evaluaciones de los visitantes, como la bondad, la tristeza, el asco, la sorpresa, el miedo, la alegría y la ira. El estudio 3 confirmó, mediante un análisis de regresión, que las características cognitivas y las emociones asociadas a los parques temáticos tienen un efecto significativo en la imagen global. Estas conclusiones tienen importantes implicaciones para los gestores de los parques temáticos, ya que proporcionan orientación para comprender las necesidades de los clientes, identificar los atributos negativos percibidos y saber cómo mejorar las experiencias de los visitantes.

Originalidad

Este estudio explora las características de los atributos de las imágenes cognitivas y afectivas de los parques temáticos y su impacto en la imagen global, enriqueciendo así la investigación sobre las connotaciones de la teoría cognitivo-afectiva. En particular, este estudio introduce y analiza cuantitativamente por primera vez el concepto de parque temático mediante un análisis de datos a gran escala, que concilia empíricamente las contradicciones que existían en revisiones anteriores de las distintas definiciones de parque temático.

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Article
Publication date: 5 February 2018

Ai Yue, Bin Tang, Yaojiang Shi, Jingjing Tang, Guanminjia Shang, Alexis Medina and Scott Rozelle

The purpose of this paper is to describe the policy and trends in rural education in China over the past 40 years; and also discuss a number of challenges that are faced by…

2237

Abstract

Purpose

The purpose of this paper is to describe the policy and trends in rural education in China over the past 40 years; and also discuss a number of challenges that are faced by China’s rural school system.

Design/methodology/approach

The authors use secondary data on policies and trends over the past 40 years for preschool, primary/junior high school, and high school.

Findings

The trends over the past 40 years in all areas of rural schooling have been continually upward and strong. While only a low share of rural children attended preschool in the 1980s, by 2014 more than 90 percent of rural children were attending. The biggest achievement in compulsory education is that the rise in the number of primary students that finish grade 6 and matriculate to junior high school. There also was a steep rise of those going to and completing high school. While the successes in upscaling rural education are absolutely unprecedented, there are still challenges.

Research limitations/implications

This is descriptive analysis and there is not causal link established between policies and rural schooling outcomes.

Practical implications

The authors illustrate one of the most rapid rises of rural education in history and match the achievements up with the policy efforts of the government. The authors also explore policy priorities that will be needed in the coming years to raise the quality of schooling.

Originality/value

This is the first paper that documents both the policies and the empirical trends of the success that China has created in building rural education from preschool to high school during the first 40 years of reform (1978-2018). The paper also documents – drawing on the literature and the own research – the achievements and challenges that China still face in the coming years, including issues of gender, urbanization, early childhood education and health and nutrition of students.

Details

China Agricultural Economic Review, vol. 10 no. 1
Type: Research Article
ISSN: 1756-137X

Keywords

Available. Content available
Book part
Publication date: 10 July 2019

Anna Visvizi, Miltiadis D. Lytras, Wadee Alhalabi and Xi Zhang

Abstract

Details

The New Silk Road Leads through the Arab Peninsula: Mastering Global Business and Innovation
Type: Book
ISBN: 978-1-78756-680-4

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Article
Publication date: 12 January 2024

Jingjing Xing, Jun Zhang and Xue Wang

This study investigates how food safety trust works as a critical moderator in the Chinese online fresh agricultural market based on an extended technology acceptance model.

516

Abstract

Purpose

This study investigates how food safety trust works as a critical moderator in the Chinese online fresh agricultural market based on an extended technology acceptance model.

Design/methodology/approach

The authors propose a research model that integrates attributes from the technology acceptance model, perceived product quality, logistics service quality, risk, and food safety trust. Structural equation modeling was applied to estimate the causal relationships using data from 851 Chinese customers.

Findings

The results indicated that perceived usefulness, product quality, and logistics service quality significantly enhance Chinese customers' intention to shop online for fresh agricultural products. Further, the positive effects increase when customer trust in food safety changes from low to high. In contrast, perceived risk reduces Chinese customers' willingness to engage in online shopping, but the negative influence is weaker for customers with high trust in food safety than for those with low trust. However, perceived ease of use plays an insignificant role in predicting online purchase intention and the impact does not vary depending on food safety trust.

Originality/value

This study suggests managers should consider the important moderating role of food safety trust to make effective strategies for fresh agricultural e-commerce development in China.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 36 no. 7
Type: Research Article
ISSN: 1355-5855

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