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Article
Publication date: 29 October 2019

Chao Zhen Yang, Zhiwei Guo and Changkun Xu

Frictions in cylinder liner-piston ring often cause an inevitable loss of energy loss in the diesel engine. This study aims at evaluating the effect of depths in the cylinder…

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Abstract

Purpose

Frictions in cylinder liner-piston ring often cause an inevitable loss of energy loss in the diesel engine. This study aims at evaluating the effect of depths in the cylinder liner groove texture on friction, wear and sealing performances.

Design/methodology/approach

Five depths of groove texture cylinder liners (50, 100, 150, 200, 250 µm) were fabricated, and experiments were carried out using a special-purpose diesel engine tester. Comparative analyses of cylinder liner contact resistances, piston ring wear losses and surface appearances were conducted with respect to different surface textures and applied loads.

Findings

Under no-load conditions, the cylinder liner with a 100 deep thread groove can significantly improve sealing and optimize its lubrication performance. On the other hand, the sealing is highly correlated with the depth of groove and the load within the cylinder liner. Under loaded conditions, the thread groove has less effect on the sealing performance.

Originality/value

The findings can provide feasible basis for the tribological design and production of diesel engines.

Details

Industrial Lubrication and Tribology, vol. 72 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 29 February 2024

Zhen Chen, Jing Liu, Chao Ma, Huawei Wu and Zhi Li

The purpose of this study is to propose a precise and standardized strategy for numerically simulating vehicle aerodynamics.

Abstract

Purpose

The purpose of this study is to propose a precise and standardized strategy for numerically simulating vehicle aerodynamics.

Design/methodology/approach

Error sources in computational fluid dynamics were analyzed. Additionally, controllable experiential and discretization errors, which significantly influence the calculated results, are expounded upon. Considering the airflow mechanism around a vehicle, the computational efficiency and accuracy of each solution strategy were compared and analyzed through numerous computational cases. Finally, the most suitable numerical strategy, including the turbulence model, simplified vehicle model, calculation domain, boundary conditions, grids and discretization scheme, was identified. Two simplified vehicle models were introduced, and relevant wind tunnel tests were performed to validate the selected strategy.

Findings

Errors in vehicle computational aerodynamics mainly stem from the unreasonable simplification of the vehicle model, calculation domain, definite solution conditions, grid strategy and discretization schemes. Using the proposed standardized numerical strategy, the simulated steady and transient aerodynamic characteristics agreed well with the experimental results.

Originality/value

Building upon the modified Low-Reynolds Number k-e model and Scale Adaptive Simulation model, to the best of the authors’ knowledge, a precise and standardized numerical simulation strategy for vehicle aerodynamics is proposed for the first time, which can be integrated into vehicle research and design.

Details

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

Keywords

Article
Publication date: 16 July 2021

Chao Ma, (George) Zhen Xiong Chen and Xinhui Jiang

This paper aims to build a moderate mediation model to delineate when and how employee with perceived overqualification will exert extra effort and therefore engage in more…

Abstract

Purpose

This paper aims to build a moderate mediation model to delineate when and how employee with perceived overqualification will exert extra effort and therefore engage in more altruistic helping behavior.

Design/methodology/approach

The research hypotheses were empirically tested using multitime and multisource survey data. Given the nested nature of data (i.e. 52 immediate supervisors rated 143 subordinates), multilevel structural equation modeling analyses within Mplus were conducted to test the proposed model.

Findings

The results support the proposed moderated mediation effect and indicate that perceived overqualification is positively related to extra effort on a condition that there is either strong desire for higher workplace status or more developmental job opportunities. The extra effort will subsequently lead to more altruistic helping behavior.

Practical implications

Based on the findings of this paper, human resource managers should consider the job applicant’s desire for workplace status and the organizational context the employer can provide when hiring overqualified employees. Second, organizations should carefully conduct job design to improve overqualified employees’ on-the-job developmental experiences. Third, training programs should be conducted to help satisfy needs and improve workplace status of overqualified employees, so that they can exert extra job effort and engage in pro-organizational behaviors.

Originality/value

Drawing on motivation–opportunity–ability theory, this paper extends the limited understanding of important boundary conditions under which perceived overqualification can be beneficial. The findings add to the knowledge on extant literature by identifying altruistic helping behavior as a new outcome of perceived overqualification.

Details

Personnel Review, vol. 51 no. 6
Type: Research Article
ISSN: 0048-3486

Keywords

Article
Publication date: 22 April 2022

Xiangming Chen, Qunhui Ou, Chao An and Dongyun Zhang

The purpose of this study is to provide an alternative approach to teacher learning on top of the usual practices of listening to experts' lectures and conducting school-based…

Abstract

Purpose

The purpose of this study is to provide an alternative approach to teacher learning on top of the usual practices of listening to experts' lectures and conducting school-based activities among peers in China. A boundary-crossing lesson study (BCLS) through school-university partnership served as an example to illustrate how a class teacher's mindset changed towards her students in equal interactions with university scholars.

Design/methodology/approach

With the lenses of action science theory and boundary-crossing learning theory, the study used qualitative research approach to collect and analyze data. One Chinese primary school class teacher from a workshop on narrative action research was selected as the case for this study. Interviewing, observation and document analysis were used to collect data. Data analysis methods included categorization and contextualization of the teacher's mindset change towards her student.

Findings

The case teacher, Mrs. Li, collaborated closely in paired teaching with her university partner AP Yu in all the four phases of their BCLS. Each phase was marked with an interactive event such as dialogic illumination, reflexive theorization, embodied conversation, and fusion of teacher and trainer roles. With inspirational trust as a major interactive mechanism, Mrs. Li jumped out of her single-loop learning (changing strategies according to results) to double-loop learning (changing both strategies and values/values). As a result, her mindset changed from attribution to appreciation towards her low-achieving student.

Originality/value

This study made contributions in two ways. First, it examined a class teacher's mindset change towards her student, rather than that of subject matter teachers towards their teaching materials and methods. Second, it revealed how reflective interactions in a special kind of BCLS by school teachers and university scholars may promote the teacher's mindset change. The findings further confirm that having differences as boundaries is not enough for teacher learning. For deep learning like Mrs. Li's mindset change, it requires a respectful and inspirational relationship between school teachers and university scholars in the BCLS.

Details

International Journal for Lesson & Learning Studies, vol. 11 no. 2
Type: Research Article
ISSN: 2046-8253

Keywords

Article
Publication date: 28 June 2013

Sheau‐yueh J. Chao

The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and…

Abstract

Purpose

The purpose of this paper is to provide the historical background of genealogical records and analyze the value of Chinese genealogical research through the study of names and genealogical resources.

Design/methodology/approach

The paper examines the historical evolution and value of Chinese genealogical records, with the focus on researching the Islamic Chinese names used by the people living in Guilin. The highlight of this paper includes the analysis and evolution of the Islamic Chinese names commonly adopted by the local people in Guilin. It concludes with the recommendations on emphasizing and making the best use of genealogical records to enhance the research value of Chinese overseas studies.

Findings

The paper covers the history of Islam and describes how the religion was introduced into China, as well as Muslims' ethnicity and identity. It also places focus on the importance of building a research collection in Asian history and Chinese genealogy.

Research limitations/implications

This research study has a strong subject focus on Chinese genealogy, Asian history, and Islamic Chinese surnames. It is a narrow field that few researchers have delved into.

Practical implications

The results of this study will assist students, researchers, and the general public in tracing the origin of their surnames and developing their interest in the social and historical value of Chinese local history and genealogies.

Social implications

The study of Chinese surnames is, by itself, a particular field for researching the social and political implications of contemporary Chinese society during the time the family members lived.

Originality/value

Very little research has been done in the area of Chinese local history and genealogy. The paper would be of value to researchers such as historians, sociologists, ethnologists and archaeologists, as well as students and anyone interested in researching a surname origin, its history and evolution.

Article
Publication date: 6 December 2018

Zhen Yan, Dong Jiang, Xiaoming Gao, Can Zhang, Ming Hu, Dapeng Feng, Jiayi Sun, Lijun Weng and Chao Wang

This paper aims to study the tribological behavior of the WS2/oil-impregnated porous polyimide (PPI) solid/liquid composite system, in which both PFPE (perfluoropolyether) and…

Abstract

Purpose

This paper aims to study the tribological behavior of the WS2/oil-impregnated porous polyimide (PPI) solid/liquid composite system, in which both PFPE (perfluoropolyether) and SiCH (silahydrocarbons) oils with different hydrocarbon chains were used, respectively. Lubricating mechanism of the composite system was also explored.

Design/methodology/approach

The tribological behaviors of the WS2 films against the PPI cylindrical pins before and after immersing oil were evaluated under different loads by a reciprocating-type ball-on-disc tribometer.

Findings

The composite system exhibited the low and stable friction coefficient after the running-in stage, and the lubricant oil played a positive effect. It was found that the WS2/PFPE composite system exhibited more excellent lubricating property, although sole SiCH far exceeds PFPE in lubrication. The abnormal phenomenon mainly resulted from the influence of the oil amount. XRD results on the wear track surfaces indicated that PFPE and SiCH oils with different hydrocarbon chains were likely to preferentially adsorb to the edge plane and basal plane of the WS2 crystals, respectively.

Originality/value

In previous studies, liquid lubricants were directly dripped or spin-coated on the solid lubricant surface. Based on its potential advantage in application, the tribological behavior and mechanism of the solid lubricating film/oil-impregnated PPI composite system were investigated in this study.

Details

Industrial Lubrication and Tribology, vol. 71 no. 3
Type: Research Article
ISSN: 0036-8792

Keywords

Article
Publication date: 1 August 1998

Jaroslav Mackerle

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder…

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Abstract

This paper gives a review of the finite element techniques (FE) applied in the area of material processing. The latest trends in metal forming, non‐metal forming, powder metallurgy and composite material processing are briefly discussed. The range of applications of finite elements on these subjects is extremely wide and cannot be presented in a single paper; therefore the aim of the paper is to give FE researchers/users only an encyclopaedic view of the different possibilities that exist today in the various fields mentioned above. An appendix included at the end of the paper presents a bibliography on finite element applications in material processing for 1994‐1996, where 1,370 references are listed. This bibliography is an updating of the paper written by Brannberg and Mackerle which has been published in Engineering Computations, Vol. 11 No. 5, 1994, pp. 413‐55.

Details

Engineering Computations, vol. 15 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 August 2006

Long‐Yi Lin and Chun‐Shuo Chen

The main purpose of this study is to explore the influence of the country‐of‐origin image, product knowledge and product involvement on consumer purchase decision.

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Abstract

Purpose

The main purpose of this study is to explore the influence of the country‐of‐origin image, product knowledge and product involvement on consumer purchase decision.

Design/methodology/approach

Taiwan, China and the USA were the three countries selected for research into the country‐of‐origin, insurance and catering services. Structured questionnaires and convenience sampling were used. Samples were collected from consumers in the Taipei area. A total of 400 questionnaires were distributed with convenience sampling method, and 369 effective samples were collected, the effective rate being 92.25 percent. Stepwise regression analysis was adapted to test hypothesis.

Findings

The main findings were listed as follows: the country‐of‐origin image, product knowledge and product involvement all have a significantly positive effect on consumer purchase decision; the country‐of‐origin image has a significantly positive effect on consumer purchase decisions under different product involvement; and product knowledge has significantly positive effect on consumer purchase decisions under different product involvement.

Research limitations/implications

Limitations of the study are: it is unable to infer to national consumers and to other service areas and the explanatory power of some empirical models is relative low. Implications of the study are that: a more thorough structure about consumer purchase decisions should be provided and the relationship between product knowledge and information search quantity should be verified.

Practical implications

Practical implications pf the study are that the company must face competitive strategies from many countries and also the effect of consumer product knowledge on business competitive strategy.

Originality/value

The added value of this paper is to link between theory and practice, and explore the different country‐of‐origin image, product knowledge and product involvement on consumer purchase decisions.

Details

Journal of Consumer Marketing, vol. 23 no. 5
Type: Research Article
ISSN: 0736-3761

Keywords

Article
Publication date: 18 April 2008

Sheau‐yueh J. Chao

This paper seeks to discuss the genealogical sources for Chinese immigrants as well as the settlement of Chinese in the USA and the historical evolution of Chinese names, their…

Abstract

Purpose

This paper seeks to discuss the genealogical sources for Chinese immigrants as well as the settlement of Chinese in the USA and the historical evolution of Chinese names, their origins, arrangement and development. It aims to cover the origins of various classes of Chinese surnames, followed by the content description of a traditional genealogical book for jiapu.

Design/methodology/approach

The paper researches the various ways that a Chinese person can find out about their ancestry.

Findings

The paper reveals the roles of libraries, including serving the needs of patrons interested in genealogical research, preserving and interpreting information through oral and family history projects and collaborating with other libraries through interlibrary loan, document delivery, library consortia, collection management and international resource‐sharing.

Research limitations/implications

The study provides information on where and how to locate the genealogical resources for researching the genealogy of a Chinese family.

Originality/value

The paper analyzes the value of genealogical research as a documentary source for population history, life expectancy in a clan, marriages and family connections, as well as lineage organizations and inter‐lineage relations.

Details

Collection Building, vol. 27 no. 2
Type: Research Article
ISSN: 0160-4953

Keywords

Article
Publication date: 4 July 2016

Yao-Wen Xue and Yan-Hua Zhang

To implement a risk-based regulatory approach, this paper aims to make an assessment on customers' money laundering risk and conducts some applications.

Abstract

Purpose

To implement a risk-based regulatory approach, this paper aims to make an assessment on customers' money laundering risk and conducts some applications.

Design/methodology/approach

During the transition of a regulatory approach from “rule-based” to “risk-based”, this paper considers that the area of a customer, types of business and the industries to which the customer belongs are the main indicators to judge money laundering risk of a customer. Based on the statistical analysis of 221 typical money laundering cases, first-class index weights are given by using the entropy weight method and then by combining with the membership function, this paper determines a customer’s money laundering risk levels. On the basis of the entropy weight method, this paper uses the C5.0 algorithm to construct a decision tree model and then carries out application research on customer money laundering risk assessment to verify the effectiveness of the entropy weight method and the decision tree model.

Findings

This empirical research found the weights of three key money laundering indicators: customer areas, business types and corresponding industries.

Originality/value

Asserting that current money laundering risk assessments of customers are marginal at best, this paper contends from the perspective of practice, and applies the entropy weight method and the decision tree model for money laundering risk assessment of customers.

Details

Journal of Money Laundering Control, vol. 19 no. 3
Type: Research Article
ISSN: 1368-5201

Keywords

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