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Article
Publication date: 19 July 2019

Biao Zhao, Wenfeng Ding, Weijie Kuang and Yucan Fu

This paper aims to evaluate the influence of molybdenum disulfide (MoS2) concentrations (5, 7.5, 10, 12.5 and 15 Wt.%) on the microstructure and tribological property of…

Abstract

Purpose

This paper aims to evaluate the influence of molybdenum disulfide (MoS2) concentrations (5, 7.5, 10, 12.5 and 15 Wt.%) on the microstructure and tribological property of the self-lubrication cubic boron nitride (CBN) abrasive composites.

Design/methodology/approach

Three point bending method and rotating sliding test are used to evaluate the flexural strength and tribological property of self-lubricating CBN abrasive composites. Microstructure, wear morphology of the ball and scratch are supported by scanning electron microscopy, optical microscope and three-dimensional confocal microscopy, etc.

Findings

The MoS2 concentration has a significant influence on the interface microstructure between CBN abrasives and matrix alloys, and thus, affects the flexural strength of CBN abrasive composites. The grain fracture modes of CBN abrasive composites are transformed from the transgranular fracture into intergranular fracture as the MoS2 concentrations increase. Additionally, the friction coefficient of as-sintered samples decreases with the MoS2 concentrations. The MoS2 concentrations of 10 Wt.% are final determined to fabricate self-lubricating composites in basis of the mechanical and lubricating property.

Originality/value

The ball is fabricated under vacuum sintering process. The tribological property of self-lubricating CBN abrasive composites is evaluated in terms of the friction coefficient and morphologies of the ball and scratches after rotating sliding tests.

Details

Industrial Lubrication and Tribology, vol. 71 no. 5
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 5 June 2017

Biao Zhang, Zetian Fu, Jieqiong Wang, Xiaolin Tang, Yousen Zhao and Lingxian Zhang

Farmers’ selection of vegetable marketing channels directly affects their income and is important to stable vegetable supply and food control. The purpose of this paper is…

Abstract

Purpose

Farmers’ selection of vegetable marketing channels directly affects their income and is important to stable vegetable supply and food control. The purpose of this paper is to investigate the farmers’ selection behavior of vegetable marketing channels, and to determine the key factors which affected farmer’ decision making.

Design/methodology/approach

A total of 191 valid questionnaires were collected from 50 villages in seven main vegetable production districts in Beijing urban areas from September to December 2015, yielding a response rate of 86.8 percent. The multinomial logit model was used for analysis in this study.

Findings

The results revealed that the farmers mainly selected farmers’ market, cooperative, and wholesaler to sell their vegetables, which comprised 96.57 percent of total vegetable sales. Estimation results showed that cooperative, vegetable acreage, price satisfaction, and slow sales were most important factors which influence positively the probability of opting to sell vegetables at a cooperative rather than at the farmer’s market. For wholesalers, gender of the household head and cooperative had most significantly negative effect, and age had a positive impact on farmer’s choice of market channels.

Originality/value

The results and implications obtained in the present study could help policymakers to establish a scientific-based and reasonable policy to encourage vegetable producers to participate in the circulation of vegetables in Beijing and guarantee their income in vegetable supply chain. The suggestions of this study could also be used for the improvement of the vegetable sector in other cities facing similar issues.

Details

British Food Journal, vol. 119 no. 6
Type: Research Article
ISSN: 0007-070X

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Article
Publication date: 6 June 2016

Chengyuan Wang, Biao Luo, Yong Liu and Zhengyun Wei

The paper aims to study the relationship between executives’ perceptions of environmental threats and innovation strategies and investigate the moderating effect of…

Abstract

Purpose

The paper aims to study the relationship between executives’ perceptions of environmental threats and innovation strategies and investigate the moderating effect of contextual factor (i.e. organizational slack) on such relations. It proposes a dualistic relationship between executives’ perceptions of environmental threats and innovation strategies, in which different perceptions of environmental threats will lead to corresponding innovation strategies, and dyadic organizational slack can promote such processes.

Design/methodology/approach

The paper is based on a survey with 163 valid questionnaires, which were all completed by executives. Hierarchical ordinary least-squares regression analysis is used to test the hypotheses proposed in this paper.

Findings

The paper provides empirical insights about that executives tend to choose exploratory innovation when they perceive environmental changes as likely loss threats, yet adopt exploitative innovation when perceiving control-reducing threats. Furthermore, unabsorbed slack (e.g. financial redundancy) positively moderates both relationships, while absorbed slack (e.g. operational redundancy) merely positively influences the relationship between the perception of control-reducing threats and exploitative innovation.

Originality/value

The paper bridges the gap between organizational innovation and cognitive theory by proposing a dualistic relationship between executives’ perceptions of environmental threats and innovation strategies. The paper further enriches innovation studies by jointly considering both subjective and objective influence factors of innovation and argues that organizational slack can moderate such dualistic relationship.

Details

Nankai Business Review International, vol. 7 no. 2
Type: Research Article
ISSN: 2040-8749

Keywords

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Article
Publication date: 11 July 2019

Biao Ma, Liang Yu, Man Chen, He Yan Li and Liang Jie Zheng

This paper aims to investigate the thermal characteristics of the clutch hydraulic system under various oil flow conditions. Increasing the oil flow is one of the most…

Abstract

Purpose

This paper aims to investigate the thermal characteristics of the clutch hydraulic system under various oil flow conditions. Increasing the oil flow is one of the most important approaches to reduce the clutch temperature. However, the effect of the oil flow on the clutch temperature remains to be explored.

Design/methodology/approach

The thermal resistance network model and the lumped parameter method are used to study the thermal characteristics of the clutch hydraulic system. The predicted temperature variations of the clutch and the oil are compared with experimental data.

Findings

Results demonstrate that the larger the friction power is, the higher the temperatures of the clutch and the oil are. However, the temperature growth rates of the clutch and oil present different trends: the former decreases gradually and the latter increases constantly. Additionally, increasing the oil flow within a certain range gives rise to the decrease of clutch temperature and the increase of oil temperature; nevertheless, their variation trends are gradually weakening. When the oil flow is large enough, it brings a slight effect on the clutch temperature rise.

Originality/value

This paper extends the knowledge into the oil flow supply of the clutch hydraulic system. The conclusions can provide a theoretical guidance for the oil management of the transmission system. Additionally, the thermal resistance network model is also effective and efficient for other hydraulic equipment to predict the temperature variation.

Details

Industrial Lubrication and Tribology, vol. 71 no. 6
Type: Research Article
ISSN: 0036-8792

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Article
Publication date: 6 August 2019

Jianpeng Wu, Biao Ma, Heyan Li and Chengnan Ma

The purpose of this paper is to study friction and wear properties of three types of steels against paper-based friction disc, including 65Mn, 20#steel and 30CrAl, so as…

Abstract

Purpose

The purpose of this paper is to study friction and wear properties of three types of steels against paper-based friction disc, including 65Mn, 20#steel and 30CrAl, so as to obtain the appropriate working conditions for different friction materials in the transmission system.

Design/methodology/approach

Based on actual working conditions, pin-on-disc tests are conducted on a universal material tester. The two evaluation indexes, including average friction coefficient and variation coefficient, are introduced to analyze the different friction properties among three types of steel. Furthermore, the temperature-dependent wear pattern and wear depth are subsequently studied.

Findings

The results show that 65Mn is more suitable for working under heavy load and low velocity, but 30CrAl and 20#steel are suitable for working under light load and high velocity. Moreover, wear primarily occurs on paper-based material and peaks at about 325.

Practical implications

This research of different materials and friction property for friction pairs is helpful to improve the performance and prolong the service life of transmission systems.

Originality/value

Suitable working conditions of different friction materials are obtained, and the correlation between wear and decomposition in high temperature is verified.

Details

Industrial Lubrication and Tribology, vol. 71 no. 10
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 7 March 2016

Yu Zhao, Guoyu Wang and Biao Huang

The purpose of this paper is to assess the predictive capability of the streamline curvature correction model (CCM) and investigate the unsteady vortex behavior of the…

Abstract

Purpose

The purpose of this paper is to assess the predictive capability of the streamline curvature correction model (CCM) and investigate the unsteady vortex behavior of the cloud cavitating flows around a hydrofoil.

Design/methodology/approach

The design of the paper is based on introducing the curvature correction method to the original k-ε model. Calculations of unsteady cloud cavitating flows around a Clark-Y hydrofoil are performed using both the CCM and the baseline model.

Findings

Compared with the baseline model, better agreements are observed between the predictions of the CCM model and experimental data, especially the cavity shedding process. Based on the computations, it is demonstrated that streamline curvature correction of the CCM model can effectively decrease predicted turbulence kinetic energy and eddy viscosity in cavity shedding region. This leads to the better prediction for the recirculation zone located downstream of the attached cavity, and dynamics of this recirculation zone contribute to the formation and development of the re-entrant jet.

Originality/value

The authors apply streamline curvature correction to the calculations of unsteady cloud cavitating flows and discuss the interactions between the cavitation unsteadiness and vortex structures to get an insight of the correction mechanics.

Details

Engineering Computations, vol. 33 no. 1
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 6 May 2014

Biao Sun and Yi-Ju Lo

The purpose of this paper is to define co-exploitation, co-exploration, and alliance ambidexterity from the perspective of organizational learning; to analyze how…

Abstract

Purpose

The purpose of this paper is to define co-exploitation, co-exploration, and alliance ambidexterity from the perspective of organizational learning; to analyze how knowledge bases, structural arrangements, and control mechanisms of R&D alliances influence co-exploitation and co-exploration; and to discuss how to achieve alliance ambidexterity by managing paradoxes around knowledge bases, structural arrangements, and control mechanisms.

Design/methodology/approach

This is a conceptual paper focussing on how to balance exploitation and exploration at the alliance level through managing three paradoxes of cooperation: similarity vs complementarity, integration vs modularity, and contracts vs trust.

Findings

While technological similarity, structural integration, and contracts are more likely to promote co-exploitation, technological complementarity, structural modularity, and trust are more likely to facilitate co-exploration. Alliance ambidexterity, which is beneficial for alliance performance, derives from either the combination of technological complementarity, structural integration, and contracts, or the combination of technological similarity, structural modularity, and trust temporally.

Research limitations/implications

Researchers should analyze the possibility of building alliance ambidexterity in other types of interorganizational relationships, and find other possible antecedents of interorganizational learning.

Practical implications

Managers should not simply treat R&D alliances as one of exploratory interorganizational relationships, but pay equal attention to co-exploitation and co-exploration. To achieve this balance, practitioners should combine technological complementarity with structural integration and contracts, or integrate technological similarity with structural modularity and trust.

Originality/value

This paper is one of the first contributions that analyze how an R&D alliance could gain its ambidexterity through the management of nested cooperation paradoxes.

Details

European Journal of Innovation Management, vol. 17 no. 2
Type: Research Article
ISSN: 1460-1060

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Article
Publication date: 17 October 2008

Yanghua Jin, Biao Nie and Yuchun Xiao

To identify the typical multilevel issues in social science, as well as illustrate the theoretical basis, hierarchical models and empirical exemplars of multilevel paradigm.

Abstract

Purpose

To identify the typical multilevel issues in social science, as well as illustrate the theoretical basis, hierarchical models and empirical exemplars of multilevel paradigm.

Design/methodology/approach

Hierarchical and multilevel data are extremely common in social systems, but multilevel analysis is constrained by statistical techniques. With the development of social system theory and empirical methods such as hierarchical structure modeling and latent growth modeling, multilevel paradigm can be used to analyze multilevel data. So it is necessary to identify typical multilevel phenomena in social science and discuss multilevel modeling techniques.

Findings

This paper identifies four typical multilevel phenomena in social system study: hierarchical and clustered sampling, collective construct research, longitudinal repeated measures, and event history analysis. Hierarchical structure modeling and latent growth modeling are effective multilevel analysis techniques in social science because of their advantages in the integration of social system research.

Research limitations/implications

The quality and availability of multilevel data are the main limitations regarding which model will be applied.

Practical implications

The paper can aid the provision of effective multilevel models to social workers.

Originality/value

This paper provides information on application of multilevel modeling in social science.

Details

Kybernetes, vol. 37 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

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Article
Publication date: 10 December 2018

Shufa Yan, Biao Ma and Changsong Zheng

The purpose of constructing a degradation index (DI) is to better characterize the degradation degree of mechanical transmission compared with relying solely on spectral…

Abstract

Purpose

The purpose of constructing a degradation index (DI) is to better characterize the degradation degree of mechanical transmission compared with relying solely on spectral oil data, which leads to an accurate estimation of the failure time when the transmission no longer fulfills its function.

Design/methodology/approach

The DI is modeled using a weighted average function with two desirable properties: maximizing the monotonic trend and minimizing the variance of failure threshold between different transmissions. The method includes concentration modification, data selection and data fusion steps that lead to a reasonable mechanical transmission degradation model. The proposed methodology was verified through a case study involving multispectral oil data sampled from several power-shift steering transmissions.

Findings

The results show that the DI outperforms all spectral oil data. Compared with the existing spectral oil data-based degradation modeling approach for mechanical transmissions, the present methodology provides an accurate RUL prediction.

Research limitations/implications

There are several important directions for future research: First, more degradation data (i.e. ferrography) that are tailored to the degradation modeling of mechanical transmission need to be involved. Second, more effective degradation data selection methodologies that are applicable for multiple data types need to be developed. Third, kernel methods that can fuse the nonlinear degradation data need to be investigated.

Originality/value

The novelty of this methodology lies in integrating the multiple degradation data in a unified DI. And the main contribution of this paper is to establish a new direction in degradation modeling and RUL prediction of mechanical transmission.

Details

Industrial Lubrication and Tribology, vol. 71 no. 2
Type: Research Article
ISSN: 0036-8792

Keywords

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Article
Publication date: 2 March 2015

Biao Xie, Liyuan Wang, Hao Yang, Yanhua Wang and Mingli Zhang

In response to food scares related to high levels of agro-chemical residues sometimes found on foods, consumers in China increasingly demand for organic foods. As little…

Abstract

Purpose

In response to food scares related to high levels of agro-chemical residues sometimes found on foods, consumers in China increasingly demand for organic foods. As little is known on consumer perceptions and attitudes toward organic food products, the purpose of this paper is to gain insight into the purchase of organic food products by consumers and to explore the main factors driving this process.

Design/methodology/approach

Mixed (quantitative and qualitative) market survey approaches were used to provide a potentially deeper insight into consumer’s perspective and could help get a better picture of the complex factors involved.

Findings

The main trigger for purchasing organic food products is that consumers expect them to be healthier and safer. The respondents who have bought organic food products tend to have a higher education level and disposable incomes, be families with children and be older than those who have not bought them. The main barriers to increasing the market share of organic food products are the consumers’ lack of knowledge, the relatively high price premium and the lack of availability of organic food products. Informing consumers about unique characteristics of organic production methods, the decline in the prices of and increasing the availability of organic food products to its customers might be a promising strategy to develop the market for organic food products.

Originality/value

This paper provides a unique insight into buying behavior and attitudes of organic consumers in China. The results of the research could provide information for the organic food industry to expand its market and improve its profitability and reliability.

Details

British Food Journal, vol. 117 no. 3
Type: Research Article
ISSN: 0007-070X

Keywords

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