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Book part
Publication date: 4 November 2021

Abstract

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International Perspectives in Online Instruction
Type: Book
ISBN: 978-1-80043-672-5

Book part
Publication date: 16 September 2019

Davide de Gennaro

Abstract

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Job Crafting
Type: Book
ISBN: 978-1-83867-222-5

Open Access
Book part
Publication date: 30 April 2019

S. J. Oswald A. J. Mascarenhas

Abstract

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Corporate Ethics for Turbulent Markets
Type: Book
ISBN: 978-1-78756-192-2

Article
Publication date: 11 October 2011

Gurmeet Kaur, M.L. Singh and M.S. Patterh

Fiber nonlinearities are anticipated to impose transmission limitations due to the enhanced total interaction length in long‐haul dense wavelength division multiplexing…

270

Abstract

Purpose

Fiber nonlinearities are anticipated to impose transmission limitations due to the enhanced total interaction length in long‐haul dense wavelength division multiplexing (DWDM) optical transmission systems. The purpose of this paper is to analytically study the combined effect of stimulated Raman scattering (SRS) and four‐wave mixing (FWM) in the presence of amplified spontaneous emission (ASE) noise generated by erbium‐doped fiber amplifiers (EDFAs).

Design/methodology/approach

The paper presents analytical analysis of DWDM optical transmission systems in the presence of two significant fiber nonlinearities (SRS and FWM).

Findings

Simple expressions are derived to study the dependence of signal‐to‐noise ratio (SNR) on the amplifier spacing between two consecutive amplifiers.

Originality/value

The authors have analytically studied the combined effect of SRS and FWM in the presence of ASE noise generated by EDFAs. The novelty of the work is that it has considered all the three factors simultaneously and the expressions are derived for calculation of SNR.

Details

Journal of Engineering, Design and Technology, vol. 9 no. 3
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 30 March 2010

Gurmeet Kaur, M.L. Singh and M.S. Patterh

The current generation of light wave systems benefit from increased transmission distance by using optical amplification and increased capacity by using dense wavelength…

Abstract

Purpose

The current generation of light wave systems benefit from increased transmission distance by using optical amplification and increased capacity by using dense wavelength division multiplexing (DWDM) technology. The reach of present systems is limited by the noise contributed by the used amplifiers, combined with nonlinear effects from transmission. This paper aims to address these issues.

Design/methodology/approach

The nature and extent of degradations in the optical DWDM systems due to these limiting factors have been discussed in this paper.

Findings

It has been learnt that stimulated Raman scattering (SRS), four wave mixing (FWM) and amplified spontaneous emission (ASE) are the important factors in optical DWDM systems. These factors limit the system capacity of the transmission systems drastically.

Originality/value

It can be concluded from the discussion that while designing an efficient DWDM system, an optimization of the channel separation and the amplifier separation is required to minimize the nonlinear effects (FWM and SRS) along with the ASE noise introduced by inline optical amplifications.

Details

Journal of Engineering, Design and Technology, vol. 8 no. 1
Type: Research Article
ISSN: 1726-0531

Keywords

Article
Publication date: 14 June 2019

Makram Elfarhani, Ali Mkaddem, Saeed Rubaiee, Abdessalem Jarraya and Mohamed Haddar

The purpose of this paper is to cover an experimental investigation of the impulse response of the foam-mass system (FMS) to unveil some of the foam dynamic behavior…

Abstract

Purpose

The purpose of this paper is to cover an experimental investigation of the impulse response of the foam-mass system (FMS) to unveil some of the foam dynamic behavior features needed to optimize the impact comfort of seat-occupant system. The equation of motion of the studied system is modeled as a sum of a linear elastic, pneumatic damping and viscoelastic residual forces. An identification methodology based on two separated calibration processes of the viscoelastic parameters was developed.

Design/methodology/approach

The viscoelastic damping force representing the foam short memory effects was modeled through the hereditary formulation. Its parameters were predicted from the free vibrational response of the FMS using iterative Prony method for autoregressive–moving–average model. However, the viscoelastic residual force resulting in the long memory effects of the material was modeled with fractional derivative term and its derivative order was predicted from previous cyclic compression standards.

Findings

The coefficients of the motion law were determined using closed form solution approach. The predictions obtained from the simulations of the impulse and cyclic tests are reasonably accurate. The physical interpretations as well as the mathematical correlations between the system parameters were discussed in details.

Originality/value

The prediction model combines hereditary and fractional derivative formulations resulting in short and long physical memory effects, respectively. Simulation of impulse and cyclic behavior yields good correlation with experimental findings.

Details

Multidiscipline Modeling in Materials and Structures, vol. 15 no. 4
Type: Research Article
ISSN: 1573-6105

Keywords

Article
Publication date: 11 October 2021

Dyanne Brendalyn Mirasol-Cavero and Lanndon Ocampo

University department efficiency evaluation is a performance assessment on how departments use their resources to attain their goals. The most widely used tool in…

Abstract

Purpose

University department efficiency evaluation is a performance assessment on how departments use their resources to attain their goals. The most widely used tool in measuring the efficiency of academic departments in data envelopment analysis (DEA) deals with crisp data, which may be, often, imprecise, vague, missing or predicted. Current literature offers various approaches to addressing these uncertainties by introducing fuzzy set theory within the basic DEA framework. However, current fuzzy DEA approaches fail to handle missing data, particularly in output values, which are prevalent in real-life evaluation. Thus, this study aims to augment these limitations by offering a fuzzy DEA variation.

Design/methodology/approach

This paper proposes a more flexible approach by introducing the fuzzy preference programming – DEA (FPP-DEA), where the outputs are expressed as fuzzy numbers and the inputs are conveyed in their actual crisp values. A case study in one of the top higher education institutions in the Philippines was conducted to elucidate the proposed FPP-DEA with fuzzy outputs.

Findings

Due to its high discriminating power, the proposed model is more constricted in reporting the efficiency scores such that there are lesser reported efficient departments. Although the proposed model can still calculate efficiency no matter how much missing and unavailable, and uncertain data, more comprehensive data accessibility would return an accurate and precise efficiency score.

Originality/value

This study offers a fuzzy DEA formulation via FPP, which can handle missing, unavailable and imprecise data for output values.

Article
Publication date: 3 February 2020

Mohamad Amin Kaviani, Alireza Peykam, Sharfuddin Ahmed Khan, Nadjib Brahimi and Raziyeh Niknam

The purpose of this paper is to develop a combined intuitionistic fuzzy analytic hierarchy process (IFAHP) and fuzzy multi-objective optimization approach to select…

Abstract

Purpose

The purpose of this paper is to develop a combined intuitionistic fuzzy analytic hierarchy process (IFAHP) and fuzzy multi-objective optimization approach to select suppliers and allocate the orders to them in the bottled water production context.

Design/methodology/approach

First, the primary weights of criteria associated with the supplier selection problem are calculated using the IFAHP technique. Then a fuzzy multi-objective optimization model is developed to allocate the appropriate amount of orders to each supplier.

Findings

The proposed methodology has been successfully implemented in the case of an Iranian food company in its bottled water factory. Results demonstrate our model is capable of practically handling the uncertainty in DMs’ preference that leads to effective and efficient supplier selection and order allocation decisions.

Originality/value

The authors develop a novel hybrid decision-making tool to tackle the uncertainty in decision-makers’ opinions with a demonstrated applicability and some promising outcomes in efficiently allocating the order quantity to suppliers in the area of bottled water production.

Details

Journal of Modelling in Management, vol. 15 no. 2
Type: Research Article
ISSN: 1746-5664

Keywords

Article
Publication date: 5 February 2018

Xiaoyu Gu, Petros Ieromonachou, Li Zhou and Ming-Lang Tseng

Batteries installed on electric vehicles (EVs) should normally be removed when their capacity falls to 70-80 per cent, but they are still usable for other purposes, such…

1365

Abstract

Purpose

Batteries installed on electric vehicles (EVs) should normally be removed when their capacity falls to 70-80 per cent, but they are still usable for other purposes, such as energy storage. This paper studies an EV battery closed-loop supply chain (CLSC) consisting of a battery manufacturer and a remanufacturer. The manufacturer produces new batteries by using natural resources, while the remanufacturer collects returned batteries and makes decisions based on the return quality, that is, to reuse or recycle. The purpose of this paper is to maximise the individual profits through optimising the amount of manufacturing and remanufacturing, respectively, and optimising the purchase price of returned batteries.

Design/methodology/approach

Based on the Nash equilibrium, this paper develops a three-period model in the CLSC. In period 1, batteries are made from raw materials; in period 2, returned batteries from period 1 are sorted into low quality and high quality. Some high-quality returns can be reused for other purposes while those non-reusable returns are recycled into materials. In period 3, all the returns are recycled into materials. The analytical results are derived.

Findings

The result of the analyses suggest that first, among the variables that affect the (re-)manufacturing decision, the purchase price for returned batteries plays a critical role. In particular, the price of low-quality returns has more influence than the price of high quality returns. Second, the higher purchase price for re-usable returns does not necessarily lead to a higher return rate of reusable returns. Third, the manufacturer’s profit is normally higher than the remanufacturer’s. This suggests the need to design incentives to promote the remanufacturing sector. And finaly, although it is appreciated that maximising the utilisation of batteries over the life-cycle would benefit the environment, the economic benefit needs further investigation.

Originality/value

Although the CLSC has been widely studied, studies on the EV battery CLSC are scarce. The EV battery CLSC is particularly challenging in terms of the reusability of returns because used EV batteries cannot be reused for the original purpose, which complicates CLSC operations. This paper explores the interrelationship between manufacturer and remanufacturer, explaining the reasons why recycling is still underdeveloped, and suggests the possibility of enhancing remanufacturing profitability.

Details

Industrial Management & Data Systems, vol. 118 no. 1
Type: Research Article
ISSN: 0263-5577

Keywords

Book part
Publication date: 2 July 2020

Vibha Hetu

This chapter sets out to explore whether the lineage of social change and social development has led to any change in public attitudes towards female rape victims. People…

Abstract

This chapter sets out to explore whether the lineage of social change and social development has led to any change in public attitudes towards female rape victims. People campaigned for the amendments in the rape laws and raised their voices to support concern for the security and dignity of women but overlooked the reality of the attitudes that victims face when they seek help. Victims are continued to be seen as a scar on the fabric of society which bears strong cultural and social norms echoing patriarchal values. The research study collected data from a sample of 130 family members of female victims of rape and 100 people from areas where rapes were predominantly reported in Delhi City. The findings that follow are that: those sampled reacted insensitively to the victims of rape. In addition to this they increased control over their female family members fearing that they would be raped. For those in the study, rape continues to be viewed as bringing shame to victims and their families.

Details

The Emerald Handbook of Feminism, Criminology and Social Change
Type: Book
ISBN: 978-1-78769-956-4

Keywords

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