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Article
Publication date: 11 July 2017

Chrysanthos Maraveas

The DELTA® beam composite floor system is a recently developed shallow floor type that has seen many applications in contemporary construction. It involves partially…

Abstract

Purpose

The DELTA® beam composite floor system is a recently developed shallow floor type that has seen many applications in contemporary construction. It involves partially encasing DELTA® steel beams in concrete, with the lower flange remaining exposed. Besides the satisfactory behavior of the system at ambient conditions, understanding its response under elevated temperatures is critical in evaluating its overall performance. Despite certification from the manufacturing company that the system has adequate fire resistance, its behavior under fire conditions has neither been investigated to depth nor reported in detail. The purpose of this paper is the detailed numerical investigation of their behavior in fire. For this reason, the finite element method was implemented in this paper to simulate the response of such beams subjected to fire. Material properties were modeled according to the Eurocodes. The coupled thermal-structural parametric analyses involved four different variations of the “shortest” and “deepest” cross-section (eight case studies in total) specified by the manufacturing company. Other simulations of these cross-sections, in which either the thermal expansion or the structural load were not taken into account, were carried out for comparison purposes.

Design/methodology/approach

The methodology for simulating such systems, which has been successfully implemented and validated against fire test results elsewhere (Maraveas et al., 2012) was also followed here. To investigate the statement made by Maraveas et al. (2014) and the equations proposed by Zaharia and Franssen (2012) that the insulation is not so effective for “short” cross-sections, two beams, one with a D20-200 (Deltabeam Technical Manual, 2013) cross-section (shallowest section) and one with a D50-600 (Deltabeam Technical Manual, 2013) cross-section (deepest section), were simulated in this paper for comparison purposes. Additionally, reasonable assumptions were made for the cross-sectional dimensions not specified by the manufacturer (Deltabeam Technical Manual, 2013) and parametric analyses were carried out to investigate their effect on the structural response of the system.

Findings

Composite DELTA® beams can achieve fire resistances ranging from 120 to 180 min, depending on the depth and geometry of their cross-section, with deeper sections displaying a better fire response. The intense thermal bowing that occurs when these beams are heated from below has a more pronounced effect, in terms of thermally induced deflections for deeper sections. The satisfactory fire resistance of these beams is achieved due to the action of the concrete encased web and the reinforcement which compensate for the loss of the exposed lower flange. Increasing the thickness of the web in deeper sections improves their fire rating up to 180 min. The thickness of the lower flange affects the fire rating of the beams only in a minor way.

Practical/implications

The paper describes a numerical methodology to estimate the fire resistance of complex flooring systems.

Details

Journal of Structural Fire Engineering, vol. 8 no. 4
Type: Research Article
ISSN: 2040-2317

Keywords

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Article
Publication date: 3 May 2016

Rui Zhou, Johnny Siu-Hang Li and Jeffrey Pai

The application of weather derivatives in hedging crop yield risk is gaining more interest. However, the further development of weather derivatives – particularly…

Abstract

Purpose

The application of weather derivatives in hedging crop yield risk is gaining more interest. However, the further development of weather derivatives – particularly exchange-traded – in the agricultural sector has been impeded by concerns over their hedging performance. The purpose of this paper is to develop a new framework to derive the optimal hedging strategy and evaluate hedging effectiveness.

Design/methodology/approach

This framework incorporates a stochastic temperature model, a crop yield model, a risk-neutral pricing method and a profit optimization procedure. Based on a large number of simulated scenarios, the authors study crop yield hedge for a future year. The authors allow the hedger to choose from different types of exchange-traded weather derivatives, and examine the impact of various factors on the optimal hedging strategy.

Findings

The analysis shows that hedging objective, pricing method and geographical location of the hedged exposure all play important roles in choosing the best hedging strategy and assessing hedging effectiveness.

Originality/value

This framework is forward-looking, because it focusses on the crop yield hedge for a future year rather than on the historical hedging effectiveness often studied in literature. It utilizes the most up-to-date information related to temperature and crop yield, and hence produces a hedging strategy which is more relevant to the year under consideration.

Details

Agricultural Finance Review, vol. 76 no. 1
Type: Research Article
ISSN: 0002-1466

Keywords

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Article
Publication date: 1 April 1994

Moldflow is fundamental to the concept of Granular Injected Paint Technology (GIPT) for in‐mould painting of injection moulded parts which is at present in an advanced…

Abstract

Moldflow is fundamental to the concept of Granular Injected Paint Technology (GIPT) for in‐mould painting of injection moulded parts which is at present in an advanced state of development. Funded by the EPIC club of 25 companies, the work is being carried out at the Rover Advanced Technology Centre at Warwick University.

Details

Pigment & Resin Technology, vol. 23 no. 4
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 March 1950

Alun D. Edwards

THE performance of civil aircraft having pure jet engines as opposed to turbine‐propeller engines will be considered since it is thought that for the latter the methods…

Abstract

THE performance of civil aircraft having pure jet engines as opposed to turbine‐propeller engines will be considered since it is thought that for the latter the methods usually adopted for piston‐engined aircraft are on the whole applicable. It will be assumed that the performance of the jet engine (i.e. its thrust and fuel consumption at various r.p.m., forward speeds and altitudes) is given and that the aerodynamic properties of the aircraft in its various configurations are known.

Details

Aircraft Engineering and Aerospace Technology, vol. 22 no. 3
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 14 January 2014

Mahshid Montazeri, Ali Shams Nateri and Keivan Ansari

In this article, a simple system will be presented to measure reflectance of metallic surfaces quickly and precisely based on goniospectrophotometric geometry. The paper…

Abstract

Purpose

In this article, a simple system will be presented to measure reflectance of metallic surfaces quickly and precisely based on goniospectrophotometric geometry. The paper aims to discuss these issues.

Design/methodology/approach

This system works by capturing reflected light from different colored patches by digital camera and with the knowledge of spectral power distribution of light source and defined observer, reflection of each sample can be reproduced. By fixing the light source, the position of the detector would be eliminated to four angles of observation.

Findings

This method can achieve acceptable reconstruction accuracy for metallic samples. This approach confirmed repeatability and practicality of the simple imaging acquisition to replace spectral reflectance measurement devices in different viewing angles.

Originality/value

The reflectance of metallic samples has been measured at several angles such as 20°, 45°, 75° and 110° from specular reflection. A simple system was used to measure multi-angle reflectance of metallic surfaces by digital camera. By suggested system can be measured the reflectance without contact and limitation in the shape of surfaces. This method achieved acceptable reconstruction accuracy for metallic samples. This simple imaging acquisition is comparable with goniospectrophotometer for measuring multi-angle reflectance of metallic samples.

Details

Sensor Review, vol. 34 no. 1
Type: Research Article
ISSN: 0260-2288

Keywords

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Article
Publication date: 1 March 1976

RICHARD LOWNDES

The design and launching of Master's degree programmes in management is a major task facing the polytechnics in Britain. Having existed for some six or seven years, they…

Abstract

The design and launching of Master's degree programmes in management is a major task facing the polytechnics in Britain. Having existed for some six or seven years, they have achieved their initial objective of creating an appropriate range of first degree programmes, exhibiting the characteristics of career orientation, multi‐disciplinary structures, innovative learning methods and relevant assessment systems. The replacement of External London University Degree courses by Council for National Academic Award programmes has accompanied the conversion of the large colleges of technologies of the nineteen sixties into the polytechnics of the nineteen seventies. Many problems still exist in the first degree range: the provision of part‐time study versions to offset overgearing to full time students, the development of course network approaches, and the integration of sub‐degree work within total programmes of which first degrees are currently the main focus—in that connection the evolution of the Diploma in Higher Education could be a key item.

Details

Industrial and Commercial Training, vol. 8 no. 3
Type: Research Article
ISSN: 0019-7858

Content available
Book part
Publication date: 1 May 2019

Shiwei Chen, Kailun Feng and Weizhuo Lu

This paper aims to provide decision support for precast concrete contractors about both precast concrete supply chain strategies and construction configurations.

Abstract

Purpose

This paper aims to provide decision support for precast concrete contractors about both precast concrete supply chain strategies and construction configurations.

Design/Methodology/Approach

This paper proposes a simulation-based optimisation for supply chain and construction (SOSC) during the planning phase of PC building projects. The discrete event simulation is used to capture the characteristics of supply chain and construction processes, and calculate construction objectives under different plans. Particle swarm optimisation is combined with simulation to find optimal supply chain strategies and construction configurations.

Findings

The efficiency of SOSC is compared with the parametric simulation approach. Over 70 per cent of time and effort used to simulate and compare alternative plans is saved owing to SOSC.

Research Limitations/Implications

Building simulation model costs a lot of time and effort. The data requirement of the proposed method is high.

Practical Implications

The proposed SOSC approach can provide decision support for PC contractors by optimising supply chain strategies and construction configurations.

Originality/Value

This paper has two contributions: one is in providing a decision support tool SOSC to optimise both supply chain strategies and construction configurations, while the other is in building a prototype of SOSC and testing it in a case study.

Details

10th Nordic Conference on Construction Economics and Organization
Type: Book
ISBN: 978-1-83867-051-1

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Article
Publication date: 26 July 2021

Ahsen Ezel Bildik Dal, Yağmur Biricik and Sinan Sönmez

This study aims to provide control of liquids, especially against water-based ink on the paper and paperboard surface with natural substances, in also practical and greenway.

Abstract

Purpose

This study aims to provide control of liquids, especially against water-based ink on the paper and paperboard surface with natural substances, in also practical and greenway.

Design/methodology/approach

The paper surface was treated with natural rosin and its derivatives to obtain a hydrophobic effect and to improve printing properties. The oleoresin samples collected from Pinus nigra Arnold and Pinus pinaster Aiton trees in the controlled area and turpentine content removed was by hydrodistillation. The gum rosin (GR), fortified 10% with maleic anhydride (MGR) and esterified with 10% pentaerythritol (PMGR) samples solved in a simply alcohol and sprayed the base paper surface directly with a spray gun. Base paper samples were paperboard, bleached paper and test liner paper. Then, flexo printing was applied and printability properties were measured.

Findings

The treatment weights of these paper samples were 1.8 ± 0.5, 1.3 ± 0.5 and 0.7 ± 0.2 g/m2, respectively, compared to the base paper. Greater Cobb60 results were obtained from modified rosin samples than unmodified gum rosin-sized paperboards and the PMGR surface treatment reduces Cobb60 values by 20% and MGR treatment reduces 15% comparing to the base sheet. Then, the printing procedure was applied to the surface of the treated materials using a flexo printing system. As a result of the treatment better print density, chroma and print lightness value consumed a less hydrophobic agent and controlling water-based flexo ink on the base paper surface.

Originality/value

The unique aspect of this work was improving the hydrophobicity of the paper surfaces was achieved by spraying with natural rosin and derivatives.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

Keywords

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Article
Publication date: 10 May 2021

Rhys J. Williams, Luke Fox and Candice Majewski

This study aims to demonstrate for the first time that the cheap, commodity polymer, poly(propylene), can be successfully processed using high speed sintering, and that it…

Abstract

Purpose

This study aims to demonstrate for the first time that the cheap, commodity polymer, poly(propylene), can be successfully processed using high speed sintering, and that it can be recycled several times through the process, with little to no detriment to either the polymer itself or the parts obtained. This is significant as a step towards the realisation of high speed sintering as a technology for high-volume manufacturing.

Design/methodology/approach

A poly(propylene) powder designed for laser sintering was used to build parts on a high speed sintering machine. The unsintered powder was then collected and reused. Repeating this process allowed creation of seven generations of aged powder. A variety of characterisation techniques were then used to measure polymer, powder and part properties for each generation to discern any effects arising from ageing in the machine.

Findings

It was found that poly(propylene) could be used successfully in high speed sintering, albeit with a low build success rate. Increased powder age was found to correlate to an increase in the build success rate, changes in microscopic and bulk powder properties and improvement to the dimensional accuracy of the parts obtained. By contrast, no discernible correlations were seen between powder age and polymer molecular weight, or between powder age and the tensile properties of parts.

Originality/value

This is the first report of the use of poly(propylene) in high speed sintering. It is also first study regarding powder recyclability in high speed sintering, both in general and using poly(propylene) specifically.

Details

Rapid Prototyping Journal, vol. 27 no. 4
Type: Research Article
ISSN: 1355-2546

Keywords

Content available
Article
Publication date: 1 August 2004

Abstract

Details

Microelectronics International, vol. 21 no. 2
Type: Research Article
ISSN: 1356-5362

Keywords

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