Search results

1 – 10 of over 1000
To view the access options for this content please click here
Article

Hongya Niu, Wenjing Cheng, Wei Pian and Wei Hu

Smoke and dust emissions from industrial furnaces can do great harm to the environment and human health. This paper aims to analyze the morphology, diameter and elements…

Abstract

Purpose

Smoke and dust emissions from industrial furnaces can do great harm to the environment and human health. This paper aims to analyze the morphology, diameter and elements of the submicron particles from the furnace flues and the nearby ambient air by using two typical industrial furnaces, the sintering furnace and the electric furnace.

Design/Methodology/Approach

Two typical industrial furnaces, the sintering furnace and the electric furnace, were chosen in this study, to analyze the morphology, diameter and elements of the submicron particles from the furnace flues and the near-by ambient air.

Findings

The results show that the particles from the two furnaces are mainly in the small sizes of 0.3-0.6 μm. Particles from sintering plant flue are mainly spherical and rich in K and Cl, whereas those from the electric plant flue are mainly particles rich in metal elements, such as Zn and Fe, and have different morphology.

Originality/value

The particles in the atmosphere nearby the two furnaces contain aged particles from the flue, lots of spherical particles, rectangle particles and various aggregations. The elements of those particles are complex.

Details

World Journal of Engineering, vol. 13 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

To view the access options for this content please click here
Article

Wei Pian, Wenjing Cheng, Hongya Niu and Jingsen Fan

This study aims to focus on the submicron particles (with diameter of 0.2-1.0 μm) of the ambient air from a coal-fired power plant. A systematic examination of their…

Abstract

Purpose

This study aims to focus on the submicron particles (with diameter of 0.2-1.0 μm) of the ambient air from a coal-fired power plant. A systematic examination of their morphology, particle size and chemical element will be analyzed, so as to provide more scientific information and theoretical basis for the formation and control method of inhalable particles, as well as data support for environmental impact and ecological effects assessments.

Design/methodology/approach

In this paper, the morphology, size distribution and elemental characteristics of submicron particles from ambient air of a coal-fired power plant are studied by single particle analysis.

Findings

The results show that atmospheric particles in coal-fired power plant are mainly spherical particles, and most of them are soot aggregates adhered or coated with other particles with few rectangle particles. The particles collected in the afternoon and evening are mainly of spherical particles, and small-sized particles collected in the morning are mainly spherical ones, while the overall concentration is larger than that of the spherical particles in the size range above 0.5 μm. The results indicated that the larger-sized spherical particles have a lower concentration.

Originality/value

Coal-fired power plants are still the main supply of electricity in China, but the inhalable particles, especially sub-micron particles (0.1-1.0 μm) cannot be effectively captured by the dust removal device from the coal-fired power plant. Thus, a large amount of inhalable particles is emitted into the atmosphere, becoming the major air pollutants in China.

Details

World Journal of Engineering, vol. 13 no. 4
Type: Research Article
ISSN: 1708-5284

Keywords

To view the access options for this content please click here
Article

Lei Wu, Xue Tian, Hongyan Wang, Qi Liu and Wensheng Xiao

As a kind of NP-hard combinatorial optimization problem, pipe routing design (PRD) is applied widely in modern industries. In the offshore oil and gas industry, a…

Abstract

Purpose

As a kind of NP-hard combinatorial optimization problem, pipe routing design (PRD) is applied widely in modern industries. In the offshore oil and gas industry, a semi-submersible production platform is an important equipment for oil exploitation and production. PRD is one of the most key parts of the design of semi-submersible platform. This study aims to present an improved ant colony algorithm (IACO) to address PRD for the oil and gas treatment system when designing a semi-submersible production platform.

Design/methodology/approach

First, to simplify PRD problem, a novel mathematical model is built according to real constraints and rules. Then, IACO, which combines modified heuristic function, mutation mechanism and dynamical parameter mechanism, is introduced.

Findings

Based on a set of specific instances, experiments are carried out, and the experimental results show that the performance of IACO is better than that of two variants of ACO, especially in terms of the convergence speed and swarm diversity. Finally, IACO is used to solve PRD for the oil and gas treatment system of semi-submersible production platform. The simulation results, which include nine pipe paths, demonstrate the practicality and high-efficiency of IACO.

Originality/value

The main contribution of this study is the development of method for solving PRD of a semi-submersible production platform based on the novel mathematical model and the proposed IACO.

Details

Assembly Automation, vol. 39 no. 1
Type: Research Article
ISSN: 0144-5154

Keywords

To view the access options for this content please click here
Article

Chi-Han AI and Hung-Che Wu

External knowledge should not be limited in one zone or level. Researchers have paid more attention to the perspective of multilevel cluster networks. However, little…

Abstract

Purpose

External knowledge should not be limited in one zone or level. Researchers have paid more attention to the perspective of multilevel cluster networks. However, little research has empirically studied the various dimensions of external knowledge. The purpose of this paper is to study different levels of external knowledge, their relation with trade and non-trade interdependence and their relation with different kinds of innovations, namely, exploitation and exploration.

Design/methodology/approach

Both quantitative and qualitative research methods were adopted in this study. In terms of the quantitative research method, data were collected from 168 companies in the Shenzhen Hi-Tech Industrial Park of China using convenience sampling. As for the qualitative research method, a total of 35 interviews were carried out in this study.

Findings

The quantitative results indicate that different levels of external knowledge in the Shenzhen Hi-Tech Park have different effects. First of all, the results indicate that cross-national connections have a positive influence on trade interdependence, which helps firms to produce exploration. Second, cross-regional connections have a positive influence on both trade and non-trade interdependence, which further help firms to create innovative exploitation and exploration. Third, inter-regional connections have a positive influence on non-trade interdependence, which helps firms to increase innovative exploitation. The qualitative result makes a plausible explanation for the quantitative results. The interview results indicate that as the telecommunications industry has so much to do with China’s national security, there are several initiatives of market protection strategies and political interventions, which help firms to form different levels of knowledge flow in Shenzhen.

Research limitations/implications

There are several limitations of this study which primarily relate to the case study method. The results can be contextually generalized to the domestic-oriented cluster in developing countries.

Practical implications

This study has several managerial implications. First, this research ensures that it is important to consider the multilevel nature of external knowledge before starting with the decision-making process of a firm in a cluster. Second, all levels of administrators and managers in a company should investigate what kinds of involvement and innovation are needed and most highly valued for organizational development. Third, the research framework of this study can be applied to understand which level of external knowledge influences organizational performance.

Originality/value

This study is an initial attempt to provide an examination of external knowledge, organizational involvement and innovation performance of an industrial cluster via a mixed method.

Details

Industrial Management & Data Systems, vol. 116 no. 4
Type: Research Article
ISSN: 0263-5577

Keywords

To view the access options for this content please click here
Article

Wen Chang and James A. Busser

This study aims to understand employee career retention in the hospitality industry. Building on the socially embedded model of thriving, signaling theory and social…

Abstract

Purpose

This study aims to understand employee career retention in the hospitality industry. Building on the socially embedded model of thriving, signaling theory and social cognitive career theory (SCCT), the study examines a structural model of psychological contract fulfillment (PCF), perceived organizational support (POS), thriving, career satisfaction and career turnover intention.

Design/methodology/approach

The proposed research model was tested using structural equation modeling with responses from 300 US hospitality employees. Data were collected using an online survey available through a panel service at Qualtrics.

Findings

Empirical results supported all proposed hypotheses and confirmed the critical mediation role of thriving for workplace contextual factors and employee career retention. As predicted, both PCF and POS positively influenced employee thriving, which positively influenced career satisfaction and negatively influenced career turnover intention.

Practical implications

Findings of this study yielded several recommendations for hospitality managers, including using the concept of thriving as an indicator and a remedy for employee career development and retention.

Originality/value

Given the increased need for qualified talent and reduced career satisfaction, this study sheds light on the further understanding of sustainable employment in the hospitality industry. Using signaling theory and SCCT as an overarching framework, this study extends the socially embedded model of thriving as well as SCCT and supports combining psychological contract theory and organizational support theory to better understand hospitality career retention.

Details

International Journal of Contemporary Hospitality Management, vol. 32 no. 1
Type: Research Article
ISSN: 0959-6119

Keywords

To view the access options for this content please click here
Article

Jing Liu, Linfeng Wang, Zhifeng Shi, Wennian Yu and Huifang Xiao

The purpose of this study is to investigate the contact models for contact and vibration features of cylindrical roller bearings (CRBs). CRBs are important parts of…

Abstract

Purpose

The purpose of this study is to investigate the contact models for contact and vibration features of cylindrical roller bearings (CRBs). CRBs are important parts of rotating machinery. The contact deformation between the roller and the raceway is an essential research topic for the CRBs. The contact deformation between the roller and the raceway can greatly affect vibration characteristics and fatigue life of the CRBs. In this investigation, six different methods are adopted to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB.

Design/methodology/approach

In this paper, the contact deformations and the contact stiffnesses between the roller and the raceway of a CRB obtained by various well-known empirical methods (Lundberg’s, Palmgren’s, Houpert’s, Cheng’s and Hertzian methods) are directly compared with those by the finite element (FE) method. A two degree-of-freedom (2 DOF) dynamic model of the CRB is applied to investigate the effects of the contact stiffness obtained by different line contact deformation calculation methods on the vibration characteristics, such as the root mean square (RMS), the peak to peak (PTP), the crest factor and the kurtosis of the displacement, velocity and acceleration of the inner raceway.

Findings

The computational results show that different calculation methods for the contact deformations between rollers and raceways have significant effects on the vibrations of the CRB. It is found that that the differences of computational results obtained by Palmgren’s and Lundberg’s models with respect to the FE method are smaller than those by the other three methods, i.e. Houpert’s, Cheng’s and Hertzain models. The amplitude and peak frequency of the frequency response functions from Palmgren’s method are much more similar to those from the finite element method. The above results indicate that Palmgren’s method is a better calculation method for predicting the contact deformations and dynamics of the CRBs.

Originality/value

This work adopts six different methods to calculate the contact deformation, contact area width and contact stress between the roller and raceways of a CRB. Moreover, a vibration model of a CRB is used to investigate the effect of contact stiffness obtained by the above methods on the vibrations of the CRB. The works can give some guidance for the accurate analytical method for calculating the contact deformations between rollers and raceways and the vibrations of the CRB.

Details

Engineering Computations, vol. 36 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

To view the access options for this content please click here
Article

Engin Duran, Burcu Uzgur Duran, Diyar Akay and Fatih Emre Boran

It is of great importance for economy policy makers to comprehend the relationship between macroeconomic indicators and domestic savings, and to find out which indicator…

Abstract

Purpose

It is of great importance for economy policy makers to comprehend the relationship between macroeconomic indicators and domestic savings, and to find out which indicator is more determinative on the dynamics of domestic savings. The purpose of this paper is to analyze the degree of relationship between Turkey’s domestic savings and selected macroeconomic indicators.

Design/methodology/approach

To examine the relationship, grey relational analysis (GRA) is applied together with the entropy method to determine the weight of the indicators according to the information level they provide. The analysis covers the data of the period from 1990 to 2014. In practice, however, the data set is used by dividing into two separate periods including before and after the 2001 crisis.

Findings

The results indicate that the unemployment rate and the gross domestic product (GDP) per capita growth stand out with a relatively high degree of relationship for the period before 2001. When examining the post-2001 period, current balance ratio and GDP growth are ascertained as indicators which have a high degree of relationship with domestic savings.

Practical implications

These indicators have different aspects affecting both public and private savings. Therefore, it may be beneficial to concentrate on these indicators when designing a policy in order to increase the domestic saving rate.

Originality/value

There are many econometric models used for investigating Turkey’s macroeconomic indicators and domestic savings causality. But before now, any study which investigates relationship between macroeconomic indicators and domestic savings by GRA could not be encountered. Using one of the newest developed theories (the grey systems theory) for this subject is the significance of this research.

Details

Grey Systems: Theory and Application, vol. 7 no. 1
Type: Research Article
ISSN: 2043-9377

Keywords

To view the access options for this content please click here
Article

Erik Hilenberg, Ersin Taskin and Andrea Ehrmann

Usual lab coats are designed to protect the wearer from the splats of chemicals, oil, dirt, etc. Simple lab coats are damaged by concentrated acids, thus quickly showing…

Abstract

Purpose

Usual lab coats are designed to protect the wearer from the splats of chemicals, oil, dirt, etc. Simple lab coats are damaged by concentrated acids, thus quickly showing typical small holes along the front when worn in a laboratory where acids are used. For intense handling of acids and other chemicals, special protective lab coats with rubber or vinyl apron or chemical-resistant overalls are used. The purpose of this paper is to investigate the possibility to protect lab coats from acid damages by finishing them with commercially available hydrophobization chemicals.

Design/methodology/approach

Two commercial hydrophobic sprays were applied on cotton, polyamide and polyester lab coat materials. Contact and roll-off angles were compared with the untreated textile fabrics before typical laboratory acids were applied on the fabrics. Finally, antibacterial properties of the finished textiles were examined.

Findings

Spray 1 resulted in significantly increased hydrophobicity, while spray 2 did not have any influence on the results. With spray 1, the originally hydrophobic fabrics became more hydrophobic, and even the originally strongly hydrophilic fabrics showed large contact angles of 130–140°. Roll-off angles were significantly reduced from 40 to 50° (for the hydrophobic fabrics) or even 90° (in case of hydrophilic fabrics) to approximately 15–25°. Correspondingly, spray 1 showed an increase of the acid resistance of the finished textile fabrics of up to 30 min for the originally hydrophobic fabrics and up to 20 min for the originally hydrophilic ones, with only one polyester fabric showing no acid resistance at all, while spray 2 led to increased antibacterial properties.

Practical implications

While spray 1 can support laboratory safety by increasing the time until acids penetrate through a lab coat, spray 2 can support sterile work in a biological laboratory.

Originality/value

To the best of the authors’ knowledge, increasing the acid resistance as well as the antibacterial properties of lab coats with easily accessible sprays has not been reported before in the scientific literature.

Details

International Journal of Clothing Science and Technology, vol. 30 no. 6
Type: Research Article
ISSN: 0955-6222

Keywords

To view the access options for this content please click here
Article

Deng-Neng Chen and Ting-Peng Liang

Knowledge has been considered a crucial organizational asset for gaining competitive advantages. It is critical for a firm to maintain a knowledge composition that is…

Abstract

Purpose

Knowledge has been considered a crucial organizational asset for gaining competitive advantages. It is critical for a firm to maintain a knowledge composition that is productive. This study aims to examine the applicability of the diversity–stability principle in ecology to knowledge management and further investigate the impact of knowledge diversity on firm performance.

Design/methodology/approach

A theoretical framework for knowledge diversity and firm performance is proposed; a questionnaire survey was conducted to evaluate the research framework. Fifty-eight valid responses from experts were collected to measure knowledge strength and diversity of 20 enterprises in four industries, and financial indexes of the 20 enterprises from 2008 to 2012 were collected to analyze the research model.

Findings

The results show that higher information technology (IT) capabilities in a firm lead to higher levels of knowledge strength and diversity. The strength and diversity of knowledge in a company can improve average company performance and reduce performance variations.

Research limitations/implications

This paper presents a new perspective that applies the ecological concept of diversity to examine the value of knowledge in organizations. The findings expand our understanding of the role of IT and knowledge in organizational performance. A limitation is that the sample size is relatively small, which may limit the generalizability of the findings.

Practical implications

CEOs and chief knowledge officers can apply the findings herein to assess their organizational knowledge profiles and maintain a healthy knowledge ecology in strategic planning. They should be aware that both knowledge strength and knowledge diversity are crucial to the stability of firm performance.

Originality/value

The ecological view of knowledge management stresses the importance of maintaining a healthy intensity and diversity of knowledge at the macro level and indicates a new direction for knowledge management.

Details

Journal of Knowledge Management, vol. 20 no. 4
Type: Research Article
ISSN: 1367-3270

Keywords

To view the access options for this content please click here
Article

Tuba Çakır Çanak, Ömer Faruk Vurur and İ. Ersin Serhatlı

This paper aims to investigate effects of acrylic functionalisation of multiwalled carbon nanotubes (MWCNTs) on properties of carbon nanotubes/epoxy nanocomposites.

Abstract

Purpose

This paper aims to investigate effects of acrylic functionalisation of multiwalled carbon nanotubes (MWCNTs) on properties of carbon nanotubes/epoxy nanocomposites.

Design/methodology/approach

A number of analytical techniques, including Fourier transform infrared spectroscopy, Raman spectroscopy, scanning electron microscopy and transmission electron microscopy, were used to assess the effects of acid treatment on MWCNTs. Ultraviolet-curable coatings were fabricated by sonication and cast moulding process. The mechanical properties of MWCNTs/epoxy composites at different weight fractions were evaluated by performing tensile tests and dynamic mechanical analysis tests. Also, gel contents were examined.

Findings

It was found that addition of nanotubes monomer to epoxy formulations had significant effect on the viscoelastic and mechanical properties.

Practical implications

Improving dispersion and alignment of MWCNTs in the composite matrix will contribute to the development of resin/MWCNTs nanocomposites and promote the applications.

Originality/value

The paper establishes a method to introduce MWCNTs into epoxy matrix as a monomer to enhance the photo curable and dispersion properties of the MWCNT/epoxy films.

Details

Pigment & Resin Technology, vol. 46 no. 1
Type: Research Article
ISSN: 0369-9420

Keywords

1 – 10 of over 1000