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Article
Publication date: 28 June 2019

Amin Samimi Behbahan, Aminreza Noghrehabadi, C.P. Wong, Ioan Pop and Morteza Behbahani-Nejad

The purpose of this paper is to study thermal performance of metal foam/phase change materials composite under the influence of the enclosure aspect ratios (ratio of enclosure…

Abstract

Purpose

The purpose of this paper is to study thermal performance of metal foam/phase change materials composite under the influence of the enclosure aspect ratios (ratio of enclosure height: length). In this study, a compound metal foam/phase change material (PCM), which has been proved to be one of the most promising approaches for thermal conductivity promotion on PCMs, was used.

Design/methodology/approach

The PCM is considered initially at its melting temperature. The enclosure for all the cases has a constant volume with various aspect ratios. The left side of the enclosure is suddenly exposed to a thermal source having a constant heat flux, while the other three surfaces are kept thermally insulated. A two-dimensional numerical model considering the non-equilibrium thermal factor, non-Darcy effect and local natural convection was proposed. The coupling between velocity and pressure is solved using the SIMPLEC, and the Rhie and Chow interpolation is used to avoid the checker-board solutions for the pressure.

Findings

The effects of foam porosity and aspect ratio of the enclosure on the PCM’s melting time were investigated. The results indicated that enclosure aspect ratio plays a fundamental role in phase change of copper foam/PCM composites. For higher porosities, enclosures with bigger aspect ratios proved to led to optimal melting time. Besides, the best enclosure aspect ratio and foam porosity for a fixed-volume enclosure to have the shortest melting time are 2.1 and 91.66 per cent, respectively. However, for a specific amount of PCM inside a variable volume enclosure, the optimal melting time was for foam with ε = 95 per cent. The achieved results prove the great importance of selection of aspect ratio to benefit both conduction and convection heat transfer simultaneously.

Originality/value

The area of energy storage systems is original.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 9
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 1 March 2006

James M.W. Wong, Albert P.C. Chan and Y.H. Chiangn

Manpower is the most valuable asset in the construction industry. Based on an examination of literature, selected key data sources, and views from 29 key informants, this paper…

1098

Abstract

Manpower is the most valuable asset in the construction industry. Based on an examination of literature, selected key data sources, and views from 29 key informants, this paper addresses the important labour resource context related to the construction industry in the case of Hong Kong. These include the trends of the critical indicators of the labour market in construction and the implications of the changing markets and technology on the future pattern of skill requirements, and the government policies on construction personnel. The findings are of immense importance to anyone involved in the construction industry, particularly training organizations and policy makers in their mission to maintain a skilled, competitive and adequate workforce able to meet the future demands of the industry. The changing labour market trends and skill requirements pose challenges for construction personnel in terms of upgrading their skills. Further research is recommended to construct robust models predicting the occupational trends in labour resources for effective manpower planning and to establish a labour market information system which could lead to capturing periodic labour market signals with a view to assisting the process of policy making on various human resource development aspects of construction workforce in Hong Kong.

Details

Journal of Engineering, Design and Technology, vol. 4 no. 1
Type: Research Article
ISSN: 1726-0531

Keywords

Abstract

Details

Urban Dynamics and Growth: Advances in Urban Economics
Type: Book
ISBN: 978-0-44451-481-3

Book part
Publication date: 1 September 2014

Wolfgang G. Scherl

This chapter introduces a new theoretical framework for developing emotion-related abilities according to the emotional intelligence (EI) construct definition of Mayer, Salovey…

Abstract

This chapter introduces a new theoretical framework for developing emotion-related abilities according to the emotional intelligence (EI) construct definition of Mayer, Salovey, and Caruso (2006). The awareness, reflection, and management (ARM) model has been devised and demonstrates a triadic cycle of emotional ARM relating to affect, cognition, and behavior. The ARM model constitutes an approach to nurture emotion-related abilities (ability EI) and responds to criticism raised by Zeidner, Matthews, and Roberts (2009). The ARM Theory was corroborated by both learning theory and schools of counselling (SOC). The potential to develop emotion-related abilities in emotional awareness, reflection and reasoning, coping and management is discussed.

Details

Individual Sources, Dynamics, and Expressions of Emotion
Type: Book
ISBN: 978-1-78190-889-1

Keywords

Book part
Publication date: 11 July 2014

Yuen-Ping Ho, Pei-Chin Low and Poh-Kam Wong

This paper investigates empirically the link between entrepreneurship education programs and students’ entrepreneurial behavior, with a particular focus on the distinction between…

Abstract

This paper investigates empirically the link between entrepreneurship education programs and students’ entrepreneurial behavior, with a particular focus on the distinction between experiential and classroom-based education. We introduce a more refined measure of entrepreneurial engagement that combines entrepreneurship intention and actual steps taken to realize that intention. Using data from a survey of 836 students at the National University of Singapore (NUS), we utilize linear regression models to examine not only the direct effect of entrepreneurship education program participation on entrepreneurial engagement, but also its possible interaction effect with several psychological constructs drawn from the Theory of Planned Behavior. The results show that participation in university entrepreneurship programs, especially experiential-learning programs, has significant positive influence on students’ entrepreneurial engagement. Moreover, the effect of program participation is significantly moderated by the students’ attitudes and perceptions. The findings have important practical implications for universities in designing entrepreneurship programs on campus. The study supports the call to move toward hands-on experiential programs as a more effective way for educational institutions to influence students’ entrepreneurial behavior and encourage venture creation activity on campus. We also contribute to the literature by confirming the impact of entrepreneurship education not only on entrepreneurial intentions but also on the concrete steps taken by students toward venture creation.

Details

Innovative Pathways for University Entrepreneurship in the 21st Century
Type: Book
ISBN: 978-1-78350-497-8

Keywords

Article
Publication date: 1 March 2006

Albert P.C. Chan, Y.H. Chiang, Stephen W.K. Mak, Lennon H.T. Choy and M.W.W James

Efficient manpower planning has been recognized as a critical aspect for the development of an economy. In 2001, the Works Bureau of the Hong Kong SAR Government (predecessor of…

1850

Abstract

Efficient manpower planning has been recognized as a critical aspect for the development of an economy. In 2001, the Works Bureau of the Hong Kong SAR Government (predecessor of Environment, Transport and Works Bureau) commissioned an HKPolyU consultancy team to develop a computer‐based model to estimate the demand for different categories of construction personnel. This article presents the concept and features of the manpower demand‐forecasting model developed for the construction industry of Hong Kong. The forecasting model is formulated on the basis of the labour multiplier approach by deriving the relationship between the number of workers required and the project expenditure in the given project duration. Multipliers for 61 project types were derived for 38 labour trades using completed project data. The labour demand by occupation for each project can then be estimated by multiplying the corresponding multipliers and the estimated project expenditure. Several unique features of the model have been developed, including “normalization” and “contract cost adjustment factor”. Normalizing the labour multipliers can facilitate the prediction of occupational labour requirements at different stages of a construction project. The adjustment factor is introduced to eliminate the discrepancy between the original estimates and final contract values so as to enhance the estimation accuracy. The model can also be used to predict the number of jobs created for a given level of investment. The government can apply this model to check and compare which project types will generate most jobs before committing public money. This model could be easily adopted and adapted by foreign construction authorities while planning manpower.

Details

Construction Innovation, vol. 6 no. 1
Type: Research Article
ISSN: 1471-4175

Keywords

Article
Publication date: 1 April 1992

JAROSLAV MACKERLE

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE…

Abstract

This bibliography is offered as a practical guide to published papers, conference proceedings papers and theses/dissertations on the finite element (FE) and boundary element (BE) applications in different fields of biomechanics between 1976 and 1991. The aim of this paper is to help the users of FE and BE techniques to get better value from a large collection of papers on the subjects. Categories in biomechanics included in this survey are: orthopaedic mechanics, dental mechanics, cardiovascular mechanics, soft tissue mechanics, biological flow, impact injury, and other fields of applications. More than 900 references are listed.

Details

Engineering Computations, vol. 9 no. 4
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 29 April 2014

Guoyun Zhou, Chia-Yun Chen, Liyi Li, Zhihua Tao, Wei He and C.P. Wong

Nickel phosphorus (Ni−P) thin-films have been electrolessly deposited in an acid-plating bath with the addition of manganese sulfate monohydrate (MSM) to achieve higher resistance…

Abstract

Purpose

Nickel phosphorus (Ni−P) thin-films have been electrolessly deposited in an acid-plating bath with the addition of manganese sulfate monohydrate (MSM) to achieve higher resistance for the application of embedded resistor with value beyond 10 KΩ. As this material is being used for fabricating embedded resistors under the addition of MSM, its resistance properties including effects of MSM concentration and plating time on resistances, temperature coefficient of resistance (TCR), and resistance tolerance of embedded resistor were investigated. The paper aims to discuss these issues.

Design/methodology/approach

The structure of fabricated Ni−P film was detected by means of scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The properties of substrate, including the surface morphologies, glass transition process and boundary of copper pad and substrate surface, were performed by SEM, dynamic mechanical analysis and optical microscope, respectively. The resistance tolerances of embedded resistors were elaborated from the cases of Ni−P thin-film resistance tolerance and the size effects of resistors, respectively.

Findings

The fabricated film was found to be constructed with numerous Ni−P amorphous nanoparticles, which was believed to be the reason of increasing thin-film resistance. The Ni−P thin-films presented over one magnitude order of resistance increasing in the case of MSM concentration varied from 0 to 40 g/L. For the case of TCRs, Ni−P thin-films deposited with 20 g/L MSM exhibited low TCRs of within ±100 ppm/°C Before TR at temperature elevating from 40 to 160°C, indicating that this Ni−P thin-film belongs to the constant TCR materials according to the military standard. For the tolerance of embedded resistor, the tolerance contributed by Ni−P thin-film was obtained to be 9.8 percent, whereas the geometry tolerances were in the range of 0-20 percent according to the geometries of embedded resistor.

Originality/value

For Ni−P thin-film without MSM, its low resistance with around 100 ohm/sq. limit the values of resistor few KΩ and restricted its widespread application of embedded resistor with higher resistance beyond 10 KΩ. The authors introduced MnSO4 in Ni−P electroless plating process to improve the low resistance of Ni−P thin-film. The resistance was increased over one order of magnitude after added with 40 g/L MnSO4. Due to the specific structure, as this material is being used for fabricating embedded resistors, the electrical properties and its application properties to verify its appliance in embedded resistor were systematically investigated by means of SEM, TEM, XRD characterizations, TCRs, resistance tolerance analysis, respectively.

Article
Publication date: 1 January 1979

MALCOLM P. ATKINSON

A survey of current work on database systems is presented. The area is divided into three main sectors: data models, data languages and support for database operations. Data…

Abstract

A survey of current work on database systems is presented. The area is divided into three main sectors: data models, data languages and support for database operations. Data models are presented as the link between the database and the real world. Languages range from formal algebraic languages to attempts to use a dialogue in English to formulate queries. The support includes hardware for content addressing, database machines and software techniques for optimizing and evaluating group expressions. Mathematical models are used to organize this support. Throughout there is a tutorial component and evaluation, which in both cases is related to the application of database ideas to documentation.

Details

Journal of Documentation, vol. 35 no. 1
Type: Research Article
ISSN: 0022-0418

Book part
Publication date: 13 December 2017

Qiongwei Ye and Baojun Ma

Internet + and Electronic Business in China is a comprehensive resource that provides insight and analysis into E-commerce in China and how it has revolutionized and continues to…

Abstract

Internet + and Electronic Business in China is a comprehensive resource that provides insight and analysis into E-commerce in China and how it has revolutionized and continues to revolutionize business and society. Split into four distinct sections, the book first lays out the theoretical foundations and fundamental concepts of E-Business before moving on to look at internet+ innovation models and their applications in different industries such as agriculture, finance and commerce. The book then provides a comprehensive analysis of E-business platforms and their applications in China before finishing with four comprehensive case studies of major E-business projects, providing readers with successful examples of implementing E-Business entrepreneurship projects.

Internet + and Electronic Business in China is a comprehensive resource that provides insights and analysis into how E-commerce has revolutionized and continues to revolutionize business and society in China.

Details

Internet+ and Electronic Business in China: Innovation and Applications
Type: Book
ISBN: 978-1-78743-115-7

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