Search results

1 – 10 of over 1000
To view the access options for this content please click here
Article
Publication date: 7 January 2020

Othmane Touri, Rida Ahroum and Boujemâa Achchab

The displaced commercial risk is one of the specific risks in the Islamic finance that creates a serious debate among practitioners and researchers about its management…

Abstract

Purpose

The displaced commercial risk is one of the specific risks in the Islamic finance that creates a serious debate among practitioners and researchers about its management. The purpose of this paper is to assess a new approach to manage this risk using machine learning algorithms.

Design/methodology/approach

To attempt this purpose, the authors use several machine learning algorithms applied to a set of financial data related to banks from different regions and consider the deposit variation intensity as an indicator.

Findings

Results show acceptable prediction accuracy. The model could be used to optimize the prudential reserves for banks and the incomes distributed to depositors.

Research limitations/implications

However, the model uses several variables as proxies since data are not available for some specific indicators, such as the profit equalization reserves and the investment risk reserves.

Originality/value

Previous studies have analyzed the origin and impact of DCR. To the best of authors’ knowledge, none of them has provided an ex ante management tool for this risk. Furthermore, the authors suggest the use of a new approach based on machine learning algorithms.

Details

International Journal of Emerging Markets, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 1746-8809

Keywords

To view the access options for this content please click here
Article
Publication date: 26 June 2021

Felipe Ribeiro Teixeira, Fernando Matos Scotti, Ruham Pablo Reis and Américo Scotti

This paper aims to assess the combined effect of the Cold Metal Transfer (CMT) advanced process and of a thermal management technique (near immersion active cooling…

Abstract

Purpose

This paper aims to assess the combined effect of the Cold Metal Transfer (CMT) advanced process and of a thermal management technique (near immersion active cooling [NIAC]) on the macro and microstructure of Al wall-like preforms built by wire arc additive manufacturing (WAAM). As specific objective, it sought to provide information on the effects of the electrode-positive/electrode-negative (EP/EN) parameter in the CMT advanced process fundamental characteristics.

Design/methodology/approach

Initially, bead-on-plate deposits were produced with different EP/EN ratios, still keeping the same deposition rate, and the outcomes on the electrical signal traces and bead formation were analyzed. In a second stage, the EP/EN parameter and the layer edge to water distance (LEWD) parameter from the NIAC technique were systematically varied and the resultant macro and microstructures compared with those formed by applying natural cooling.

Findings

Constraints of EP/EN setting range were uncovered and discussed. The use of the NIAC technique favors the formation of finer grains. For a given EP/EN value, a variation in the NIAC intensity (LEWD value) showed marginal effect on grain size. When the EP/EN parameter effect is isolated, i.e. for a given LEWD setting, it was observed that an increase in the EP/EN level favors coarser grains.

Originality/value

Both the EP/EN parameter and the use of an active cooling technique (NIAC) might be used, even in combination, as effective tools for achieving proper macro and microstructure in WAAM of thin wall builds.

Details

Rapid Prototyping Journal, vol. 27 no. 6
Type: Research Article
ISSN: 1355-2546

Keywords

To view the access options for this content please click here
Article
Publication date: 1 January 1975

F.H. Reid

In both decorative and industrial applications of gold plating, but even more critically in the latter, accurate measurement of coating thickness is of vital importance to…

Abstract

In both decorative and industrial applications of gold plating, but even more critically in the latter, accurate measurement of coating thickness is of vital importance to both the manufacturer and the user. To the former, working to increasingly stringent specifications, it may, in extreme cases, mean the difference between profit and loss if an excessive thickness is inadvertently applied due to some change in electrolyte or processing conditions, or if an unduly high average thickness must be used on barrel or vat plated components to ensure a minimum requirement on functional areas. To the user, it can equally mean the difference between operational success and failure of a gold plated part if plating thickness is below specification and the means used for measurement are not sufficiently precise to detect this. Control of coating thickness in gold plating is therefore a matter of vital concern, and never more so than at the present time when, in the face of the spectacular price increases of recent years, and in the virtual absence of viable alternatives to meet the exacting demands of applications in printed circuitry, semiconductor technology and the electronics industry in general, the need for maximum economy in gold usage has become increasingly urgent, as evidenced by the vigorous efforts currently devoted to the development and improvement of selective plating techniques, and the recent interest manifest in the possible replacement of essentially pure gold coatings by alloy deposits of 18 carat and lower where these may be technically acceptable. The present article offers a wide‐ranging survey of methods available for thickness measurement, with particular reference to gold plating, but including also some techniques which, whilst not finding current use, may be of potential interest in this context. This is the second and final part of this article, the first having appeared in Volume 1, Number 1, October (1974).

Details

Circuit World, vol. 1 no. 2
Type: Research Article
ISSN: 0305-6120

To view the access options for this content please click here
Article
Publication date: 1 August 2016

Thomas D.A. Jones, David Flynn, Marc P.Y. Desmulliez, Dennis Price, Matthew Beadel, Nadia Strusevich, Mayur Patel, Chris Bailey and Suzanne Costello

This study aims to understand the influence of megasonic (MS)-assisted agitation on printed circuit boards (PCBs) electroplated using copper (Cu) electrolyte solutions to…

Abstract

Purpose

This study aims to understand the influence of megasonic (MS)-assisted agitation on printed circuit boards (PCBs) electroplated using copper (Cu) electrolyte solutions to improve plating efficiencies through enhanced ion transportation.

Design/methodology/approach

The impact of MS-assisted agitation on topographical properties of the electroplated surfaces was studied through a design of experiments by measuring surface roughness, which is characterised by values of the parameter Ra as measured by white light phase shifting interferometry and high-resolution scanning electron microscopy.

Findings

An increase in Ra from 400 to 760 nm after plating was recorded for an increase in acoustic power from 45 to 450 W. Roughening increased because of micro-bubble cavitation energy and was supported through direct imaging of the cavitation. Current thieving effect by the MS transducer induced low currents, leading to large Cu grain frosting and reduction in the board quality. Current thieving was negated in plating trials through specific placement of transducer. Wavy electroplated surfaces, due to surface acoustic waves, were also observed to reduce the uniformity of the deposit.

Research limitations/implications

The formation of unstable transient cavitation and variation of the topology of the Cu surface are unwanted phenomena. Further plating studies using MS agitation are needed, along with fundamental simulations, to determine how the effects can be reduced or prevented.

Practical implications

This study can help identify manufacturing settings required for high-quality MS-assisted plating and promote areas for further investigation, leading to the development of an MS plating manufacturing technique.

Originality/value

This study quantifies the topographical changes to a PCB surface in response to MS agitation and evidence for deposited Cu artefacts due to acoustic effects.

Details

Circuit World, vol. 42 no. 3
Type: Research Article
ISSN: 0305-6120

Keywords

To view the access options for this content please click here
Article
Publication date: 5 September 2008

Ram N. Acharya, Albert Kagan and Srinivasa Rao Lingam

The purpose of this paper is to examine the impact of online banking intensity on the financial performance of community banks.

Abstract

Purpose

The purpose of this paper is to examine the impact of online banking intensity on the financial performance of community banks.

Design/methodology/approach

This study estimates online banking intensity and bank performance indices using a combination of primary and secondary data. Online banking intensity is specified as a latent construct and estimated using web feature data collected from bank websites. An empirical profit function of a nonstandard Fourier flexible form is estimated using bank's financial data to derive a theoretically consistent performance measure. The actual impact of online banking on performance is measured by regressing the profit efficiency index against a number of correlates including online banking intensity measure.

Findings

Study results indicate that the increasing use of internet as an additional channel of marketing banking services has significantly improved the financial performance of community banks.

Practical implications

These results show that online banking improves the financial performance and should encourage community banks to adopt new information technologies and offer targeted online services.

Originality/value

This paper is the first of its kind that applies a structural equation modeling framework to develop a comprehensive online banking intensity measure, which accounts for a wide array of products and services offered online by a bank, and utilizes the estimated index in measuring the impact of internet banking intensity on bank performance.

Details

International Journal of Bank Marketing, vol. 26 no. 6
Type: Research Article
ISSN: 0265-2323

Keywords

To view the access options for this content please click here
Article
Publication date: 17 September 2019

Rafael Quelho de Macedo, Rafael Thiago Luiz Ferreira and Kuzhichalil Jayachandran

This paper aims to present experimental and numerical analyses of fused filament fabrication (FFF) printed parts and show how mechanical characteristics of printed…

Abstract

Purpose

This paper aims to present experimental and numerical analyses of fused filament fabrication (FFF) printed parts and show how mechanical characteristics of printed ABS-MG94 (acrylonitrile butadiene styrene) are influenced by the void volume fraction, cooling rate and residual thermal stresses.

Design/methodology/approach

Printed specimens were experimentally tested to evaluate the mechanical properties for different printing speeds, and micrographs were taken. A thermo-mechanical finite element model, able to simulate the FFF process, was developed to calculate the temperature fields in time, cooling rate and residual thermal stresses. Finally, the experimental mechanical properties and the microstructure distribution could be explained by the temperature fields in time, cooling rate and residual thermal stresses.

Findings

Micrographs revealed the increase of void volume fraction with the printing speed. The variations on voids were associated to the temperature fields in time: when the temperatures remained high for longer periods, less voids were generated. The Young's Modulus of the deposited filament varied according to the cooling rate: it decreased when the cooling rate increased. The influence of the residual thermal stresses and void volume fraction on the printed parts failure was also investigated: in the worst scenarios evaluated, the void volume fraction reduced the strength in 9 per cent, while the residual thermal stresses reduced it in 3.8 per cent.

Originality/value

This work explains how the temperature fields can affect the void volume fraction, Young's Modulus and failure of printed parts. Experimental and numerical results are shown. The presented research can be used to choose printing parameters to achieve desired mechanical properties of FFF printed parts.

Details

Rapid Prototyping Journal, vol. 25 no. 10
Type: Research Article
ISSN: 1355-2546

Keywords

To view the access options for this content please click here
Article
Publication date: 11 June 2018

Jason Jie Xiang Bui, Yee Yong Tan, Fu Ee Tang and Carrie Ho

This study aims to investigate the hydraulic behaviour of a pilot-scale, two-staged, vertical flow constructed wetland (VFCW) for septage treatment, in terms of factors…

Abstract

Purpose

This study aims to investigate the hydraulic behaviour of a pilot-scale, two-staged, vertical flow constructed wetland (VFCW) for septage treatment, in terms of factors such as hydraulic retention time and hydraulic loading rate and its influence on the treatment dynamics. Because of intermittent feeding mode of VFCW systems and variation in its loading, its hydraulic behaviour is highly variable and need to be understood to optimize its treatment performance.

Design/methodology/approach

Tracer test were carried out using bromide ion with varying hydraulic loading rates (HLR) of 6.82 cm/d, 9.09 cm/d and 11.40 cm/d (i.e. equivalent to 75 L/d, 100L/d and 125 L/d). Tracer data is then analysed using the Residence Time Distribution (RTD) method.

Findings

RTD analysis showed that the increase in HLR increases the average hydraulic retention time (HRT). Subsequently, the increase in HLR results in a lower recovery of effluent, resulting in poor productivity in treatment. The study also showed that the removal of nitrogen and organic matter improved with increasing HRT. However, observations show no correlation between HRT and total solids removal.

Originality/value

A performance evaluation method (by tracer) is proposed to understand the hydraulics of flow in constructed wetlands, which has not been widely studied. Additionally, the dynamics of treatment in VFCWs treating septage may also be revealed by the tracer method. The study can be applied to any constructed wetlands designed for treatment of wastewater, septage or sludge.

To view the access options for this content please click here
Article
Publication date: 14 September 2010

Felipe Ruiz‐Moreno, Antonio Ladrón‐de‐Guevara and Francisco Mas‐Ruiz

The main objective of this paper is to propose a model that allows the detection of the competitive pattern of the Spanish loans market between 1992 and 1996.

Abstract

Purpose

The main objective of this paper is to propose a model that allows the detection of the competitive pattern of the Spanish loans market between 1992 and 1996.

Design/methodology/approach

In order to achieve this objective, the paper estimates, following the New Empirical Industrial Organization paradigm, a conjectural variation model for the strategic marketing dimension of price. The model proposed allows the measurement of strategic group‐level rivalry while simultaneously considering demand, costs, and profit specifications for each bank.

Findings

The findings evidence a high degree of competition between the firms within the same strategic group. Further, the demand for loans of a firm has a positive (negative) relationship with the rivals' price (own price), with the own branch network (rivals' branch network), and with the economic activity in the regions where firm operates.

Research limitations/implications

The major limitation of this research could become from the necessity to operate with detailed information that the authors try to overcome using proxies of several non‐available variables.

Originality/value

The model proposed herein represents a contribution to previous works and also provides more information about banking competition in the sense that it estimates price competition between firms within three strategic groups.

Details

International Journal of Bank Marketing, vol. 28 no. 6
Type: Research Article
ISSN: 0265-2323

Keywords

To view the access options for this content please click here
Article
Publication date: 14 January 2014

Shyam Barua, Frank Liou, Joseph Newkirk and Todd Sparks

Laser metal deposition (LMD) is a type of additive manufacturing process in which the laser is used to create a melt pool on a substrate to which metal powder is added…

Abstract

Purpose

Laser metal deposition (LMD) is a type of additive manufacturing process in which the laser is used to create a melt pool on a substrate to which metal powder is added. The powder is melted within the melt pool and solidified to form a deposited track. These deposited tracks may contain porosities or cracks which affect the functionality of the part. When these defects go undetected, they may cause failure of the part or below par performance in their applications. An on demand vision system is required to detect defects in the track as and when they are formed. This is especially crucial in LMD applications as the part being repaired is typically expensive. Using a defect detection system, it is possible to complete the LMD process in one run, thus minimizing cost. The purpose of this paper is to summarize the research on a low-cost vision system to study the deposition process and detect any thermal abnormalities which might signify the presence of a defect.

Design/methodology/approach

During the LMD process, the track of deposited material behind the laser is incandescent due to heating by the laser; also, there is radiant heat distribution and flow on the surfaces of the track. An SLR camera is used to obtain images of the deposited track behind the melt pool. Using calibrated RGB values and radiant surface temperature, it is possible to approximate the temperature of each pixel in the image. The deposited track loses heat gradually through conduction, convection and radiation. A defect-free deposit should show a gradual decrease in temperature which enables the authors to obtain a reference cooling curve using standard deposition parameters. A defect, such as a crack or porosity, leads to an increase in temperature around the defective region due to interruption of heat flow. This leads to deviation from the reference cooling curve which alerts the authors to the presence of a defect.

Findings

The temperature gradient was obtained across the deposited track during LMD. Linear least squares curve fitting was performed and residual values were calculated between experimental temperature values and line of best fit. Porosity defects and cracks were simulated on the substrate during LMD and irregularities in the temperature gradients were used to develop a defect detection model.

Originality/value

Previous approaches to defect detection in LMD typically concentrate on the melt pool temperature and dimensions. Due to the dynamic and violent nature of the melt pool, consistent and reliable defect detection is difficult. An alternative method of defect detection is discussed which does not involve the melt pool and therefore presents a novel method of detecting a defect in LMD.

Details

Rapid Prototyping Journal, vol. 20 no. 1
Type: Research Article
ISSN: 1355-2546

Keywords

To view the access options for this content please click here
Article
Publication date: 15 April 2020

Bassam Abdallah, Mahmoud Kakhia and Walaa Zetoune

This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method…

Abstract

Purpose

This study aims to carry out the deposition of zinc sulfide (ZnS) thick films on glass and silicon (100) substrates using radio frequency (RF) magnetron sputtering method at different powers. Film structure has been analyzed by X-ray diffraction (XRD); the patterns showed that the films possesses a cubic structure with (111) preferred orientation. Photoluminance (PL) intensity of the films has been related to the crystallinity, which is varied with the power.

Design/methodology/approach

Scanning electron microscope (SEM) images have been used to discover the films’ morphology. The stoichiometry has been confirmed by energy dispersive X-ray spectroscopy (EDX) analysis. MicroRaman spectroscopy has been used to validate the film structure. Gas-sensing studies were carried out by means of a static gas chamber to sense acetone, ethanol, methanol, H2O and NH3 vapor in air ambient.

Findings

ZnS has a stoichiometric and cubic structure. The band gaps and photoluminance intensity of the films are correlated with the crystallinity, which is varied with the power. The EDX analysis approved the stoichiometry of the prepared films. Acetone, ethanol, humidity (H2O), methanol and NH3 vapor gases were used to justify the sensing properties at 25°C of the thickest ZnS film.

Originality/value

High-quality ZnS films have been obtained at different powers without annealing. Gases sensing properties at 25°C are justified for deposited ZnS films using acetone, ethanol, humidity (H2O), methanol and NH3 vapor gases. It reveals good response for NH3 and humidity vapors at room temperature; the sensing functioning at this temperature was attractive in recent research.

Details

World Journal of Engineering, vol. 17 no. 3
Type: Research Article
ISSN: 1708-5284

Keywords

1 – 10 of over 1000