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Article
Publication date: 13 September 2011

E. Baake, A. Jakovics, S. Pavlovs and M. Kirpo

The purpose of this paper is to present in‐depth numerical modelling of heat and mass exchange in industrial induction channel furnace (ICF).

Abstract

Purpose

The purpose of this paper is to present in‐depth numerical modelling of heat and mass exchange in industrial induction channel furnace (ICF).

Design/methodology/approach

The turbulent heat and mass exchange in the melt is calculated using a three‐dimensional (3D) electromagnetic model and a 3D transient large eddy simulation method. The simulation model has been verified by flow velocity and temperature measurements, which were carried out using an industrial sized channel inductor operating with Wood's metal as a low temperature model melt.

Findings

The ICF is well‐established for melting, holding and casting in the metallurgical industry. But there are still open questions regarding the heat and mass exchange in the inductor channel itself and between the channel and the melt bath. Different new designed channel geometries have been investigated numerically in order to find an optimized shape of the channel, which leads to an improved heat and mass transfer.

Originality/value

Long‐term computations for the industrial ICF have been performed. Low frequency oscillations of the temperature maximum and its position in the ICF channel are considered.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 30 no. 5
Type: Research Article
ISSN: 0332-1649

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Article
Publication date: 28 April 2020

Nandakishor Sirdeshpande and Vishwanath Udupi

Wireless communication channel provides a wide area of applications in the field of communication, distributed sensor network and so on. The prominence of the wireless…

Abstract

Purpose

Wireless communication channel provides a wide area of applications in the field of communication, distributed sensor network and so on. The prominence of the wireless communication channel is because of its robust nature and the sustainability for the precise ranging and the localization. The precision and accuracy of the wireless communication channel largely depend on the localization. The development of the wireless communication channel with improved benefits needs the accurate channel model.

Design/methodology/approach

This paper characterizes the tangential path loss model in the WINNER based wireless communication channel model. The measurements taken in the WINNER channel model are compared with the tangential path loss characterized WINNER Channel model.

Findings

The model operates well over the varying antenna orientations, measurement condition and the propagation condition. The proposed tangential path loss model is performing well over the various outdoor scenarios.

Originality/value

The proposed characterization shows change in the small-scale parameters (SSP), such as power, delay, angle of arrival and angle of departure as well as the large-scale parameters (LSP), such as RMS delay spread, shadowing, path loss and Ricean factor associated with the model.

Details

Data Technologies and Applications, vol. 54 no. 3
Type: Research Article
ISSN: 2514-9288

Keywords

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Article
Publication date: 9 July 2020

Julian Ferchow, Harry Baumgartner, Christoph Klahn and Mirko Meboldt

Internal channels produced by selective laser melting (SLM) have rough surfaces that require post-processing. The purpose of this paper is to develop an empirical model

Abstract

Purpose

Internal channels produced by selective laser melting (SLM) have rough surfaces that require post-processing. The purpose of this paper is to develop an empirical model for predicting the material removal and surface roughness (SR) of SLM-manufactured channels owing to abrasive flow machining (AFM).

Design/methodology/approach

A rheological model was developed to simulate the viscosity and power-law index of an AFM medium. To simulate the pressure distribution and velocity in the SLM channels, the fluid behavior and SR in the channels were simulated by using computational fluid dynamics. The results of this simulation were then applied to create an empirical model that can be used to predict the SR and material removal thickness. To verify this empirical model, it was applied to an actual part fabricated by SLM. The results were compared with the measurements of the SR and channel diameter subsequent to AFM.

Findings

The proposed model exhibits maximum deviation between the model and the measurement of −1.1% for the down-skin SR, −0.2% for the up-skin SR and −0.1% for material removal thickness.

Practical implications

The results of this study show that the proposed model can avoid expensive iterative tests to determine whether a given channel design leads to the desired SR after smoothing by AFM. Therefore, this model helps to design an AFM-ready channel geometry.

Originality/value

In this paper, a quantitatively validated AFM model was proposed for complex SLM channels with varying orientation angles.

Details

Rapid Prototyping Journal, vol. 26 no. 7
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 3 April 2019

Xiangzhi Wei, Xianda Li, Shanshan Wen, Yu Zheng and Yaobin Tian

For any 3D model with chambers to be fabricated in powder-bed additive manufacturing processes such as SLM and SLS, powders are trapped in the chambers of the finished…

Abstract

Purpose

For any 3D model with chambers to be fabricated in powder-bed additive manufacturing processes such as SLM and SLS, powders are trapped in the chambers of the finished model. This paper aims to design a shortest network with the least number of outlets for efficiently leaking the trapped powders.

Design/methodology/approach

This paper proposes a nonlinear objective with linear constraints for solving the channel design problem and a particle swarm optimization algorithm to solve the nonlinear system.

Findings

Structural optimization for the channel network leads to fairly short channels in the interior of the 3D models and very few outlets on the model surface, which achieves the cleaning of the powders while causing almost the least changes to the model.

Originality/value

This paper reveals the NP-harness of computing the shortest channel network with the least number of outlets. The proposed approach helps the design of lightweight models using the powder-bed additive manufacturing techniques.

Details

Rapid Prototyping Journal, vol. 25 no. 9
Type: Research Article
ISSN: 1355-2546

Keywords

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Article
Publication date: 3 January 2020

Jafar Heydari, Amin Aslani and Ali Sabbaghnia

Distribution systems usually utilize both traditional retailing channels in conjunction with e-channels. The purpose of this paper is to investigate a dual-channel supply…

Abstract

Purpose

Distribution systems usually utilize both traditional retailing channels in conjunction with e-channels. The purpose of this paper is to investigate a dual-channel supply chain, comprising a traditional retailing channel and an e-channel under disruption. By benchmarking against the centralized decision structure, the authors intend to propose a collaboration model to achieve channel coordination as well as more reliable decisions.

Design/methodology/approach

Four different channel disruption scenarios, with customers’ reaction toward disruptions, are examined, and then, optimal pricing decisions for both centralized and decentralized decision-making structures are extracted. Next, a collaboration mechanism based on the dominancy power of channel members is developed to entice all channel members to participate in channel coordination. By benchmarking the proposed collaboration model against both the decentralized/centralized structures a win–win solution is guaranteed for all channel members. In addition, the proposed model ensures more reliable decisions than the centralized structure, as it guarantees less fluctuated income levels.

Findings

This study shows, as the disruption probability grows, the channel profit decreases while the channel-retailing price increases. Furthermore, the exact alignment of the centralized decision-making approach and the proposed collaboration model is not achievable due to the problem infeasibility. Numerical experiments and sensitivity analyses benchmark the performance of the proposed collaboration mechanism against the centralized structure for the full alignment with centralized decision-making approach.

Originality/value

This study contributes to the channel conflict literature as jointly considers pricing decisions, disruptions and coordination. Further, consumers’ reaction toward disruption is analyzed through a transshipment agreement.

Details

Benchmarking: An International Journal, vol. 27 no. 3
Type: Research Article
ISSN: 1463-5771

Keywords

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Article
Publication date: 11 February 2019

Mohammad Fazli and Mehrdad Raisee

This paper aims to predict turbulent flow and heat transfer through different channels with periodic dimple/protrusion walls. More specifically, the performance of various…

Abstract

Purpose

This paper aims to predict turbulent flow and heat transfer through different channels with periodic dimple/protrusion walls. More specifically, the performance of various low-Re k-ε turbulence models in prediction of local heat transfer coefficient is evaluated.

Design/methodology/approach

Three low-Re number k-ε turbulence models (the zonal k-ε, the linear k-ε and the nonlinear k-ε) are used. Computations are performed for three geometries, namely, a channel with a single dimpled wall, a channel with double dimpled walls and a channel with a single dimple/protrusion wall. The predictions are obtained using an in house finite volume code.

Findings

The numerical predictions indicate that the nonlinear k-ε model predicts a larger recirculation bubble inside the dimple with stronger impingement and upwash flow than the zonal and linear k-ε models. The heat transfer results show that the zonal k-ε model returns weak thermal predictions in all test cases in comparison to other turbulence models. Use of the linear k-ε model leads to improvement in heat transfer predictions inside the dimples and their back rim. However, the most accurate thermal predictions are obtained via the nonlinear k-ε model. As expected, the replacement of the algebraic length-scale correction term with the differential version improves the heat transfer predictions of both linear and nonlinear k-ε models.

Originality/value

The most reliable turbulence model of the current study (i.e. nonlinear k-ε model) may be used for design and optimization of various thermal systems using dimples for heat transfer enhancement (e.g. heat exchangers and internal cooling system of gas turbine blades).

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 29 no. 3
Type: Research Article
ISSN: 0961-5539

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Article
Publication date: 3 October 2021

Guillaume Do Vale, Isabelle Collin-Lachaud and Xavier Lecocq

To cope with online competitors and new consumer behaviors, retailers need to hybrid digital and physical offerings to implement an omni-channel business model. This…

Abstract

Purpose

To cope with online competitors and new consumer behaviors, retailers need to hybrid digital and physical offerings to implement an omni-channel business model. This constitutes a digital transformation of the traditional business model. However, business cases on how traditional retailers are shifting from multi-channel to omni-channel retailing are lacking. This paper aims to explore the different issues and organizational paths during the transformation of a business model.

Design/methodology/approach

This study is based on a qualitative multiple case study of five retailers with a global reach currently implementing an omni-channel business model.

Findings

This research sheds light on three main issues encountered by retailers and the different underlying decisions when moving toward an omni-channel business model. The first relates to revenue attribution across channels, which involves rethinking traditional key performance indicators to give incentives to stores when promoting digital offers. The second issue concerns the supply chain decisions associated with cross-channel operations. The third issue relates to the delicate balance between global reach (digital channel) and local reach (specific store) for communication on social media and marketing decisions on pricing. This study provides empirical evidence about the variety of choices that retailers make to cope with the issues during the implementation of an omni-channel business model.

Originality/value

This work explores the issues faced by established firms when moving toward a new business model that is the hybridization of two existing business model managed separately. It provides comprehensive and clear illustration of how to manage such a business model transformation process that can be used by both business strategy practice and academic research.

Details

Journal of Business Strategy, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0275-6668

Keywords

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Abstract

Details

Modelling Our Future: Population Ageing, Health and Aged Care
Type: Book
ISBN: 978-1-84950-808-7

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Article
Publication date: 11 January 2008

Jae‐Eun Chung, Brenda Sternquist and Zhengyi Chen

The purpose of this study is to compare two models, traditional‐ and performance‐based, of Japanese retailers' channel relationships. The traditional model proposes…

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Abstract

Purpose

The purpose of this study is to compare two models, traditional‐ and performance‐based, of Japanese retailers' channel relationships. The traditional model proposes Japanese retailers' long‐term orientation with their supplier is an antecedent of Japanese retailers' trust and dependence on the supplier. The performance model, on the other hand, proposes significant influences of suppliers' role performance and dependence on channel relationships.

Design/methodology/approach

Data were collected from Japanese department store buyers and specialty store buyers. A total of 141 cases were analyzed using the EQS structural equation modeling software.

Findings

Results show that the traditional model had a higher explanatory power than the performance model, which indicates the strong influence of culture on Japanese channel relationships.

Research limitations/implications

Some measures have relatively poor psychometric properties. A further study should refine these measurements by exploring the meanings of these constructs from the cultural context.

Originality/value

This study provides insight into how cultural influences are embedded in distribution channel relationships.

Details

Asia Pacific Journal of Marketing and Logistics, vol. 20 no. 1
Type: Research Article
ISSN: 1355-5855

Keywords

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Article
Publication date: 27 May 2014

Christopher Durugbo

The purpose of this paper is to evaluate the benefits of using the business network channel (Bunch) approach for modelling business networks and studying the business…

Abstract

Purpose

The purpose of this paper is to evaluate the benefits of using the business network channel (Bunch) approach for modelling business networks and studying the business network evolution. Business network models put the structures of process models into context by visualising roles and communication channels for social interactions.

Design/methodology/approach

The research applies a case study-based approach involving the creation of business network visualisations to capture snapshots of an industrial firm's business network over a three-year period. A questionnaire-based study was also conducted with 18 key informants to evaluate the Bunch approach against existing business network modelling techniques.

Findings

This study shows that when business networks – as opposed to business processes – are diagrammatically modelled, patterns of relations between individuals can also be visualised and factored into how information systems are (re)designed and deployed. The study also finds that as business networks evolve, the ability to offer complementary channels of communication and coordinate business/technological information is vital to how upturns in process times improves overall business effectiveness and efficiency.

Originality/value

The major contribution of this paper is an exposition on how the Bunch approach could serve as a pedagogical tool for gaining clarity on their roles and links within the business and as an analytical tool for studying the evolution of business networks in relation to roles, links, information technologies, business strategies and business network anomalies.

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