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Article
Publication date: 25 January 2008

Yi‐Hui Liang

The purpose of this paper is to propose an accurate product reliability prediction model in order to enhance product quality and reduce product costs.

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Abstract

Purpose

The purpose of this paper is to propose an accurate product reliability prediction model in order to enhance product quality and reduce product costs.

Design/methodology/approach

This study proposes a new method for predicting the reliability of repairable systems. The novel method employed constructs a predictive model by integrating neural networks and genetic algorithms. Findings – The novel method employed constructs a predictive model by integrating neural networks and genetic algorithms. Genetic algorithms are used to globally optimize the number of neurons in the hidden layer, the learning rate and momentum of neural network architecture. Research limitations/implications – This study only adopts real failure data from an electronic system to verify the feasibility and effectiveness of the proposed method. Future research may use other product's failure data to verify the proposed method. The proposed method is superior to ARIMA and neural network model prediction techniques in the reliability of repairable systems. Practical implications – Based on the more accurate analytical results achieved by the proposed method, engineers or management authorities can take follow‐up actions to ensure that products meet quality requirements, provide logistical support and correct product design. Originality/value – The proposed method is superior to other prediction techniques in predicting the reliability of repairable systems.

Details

International Journal of Quality & Reliability Management, vol. 25 no. 2
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 1 July 2006

Andrzej Demenko and Jan Sykulski

The aim of this paper is to develop network models of an electromagnetic field containing both eddy and displacement currents. The proposed network models provide good physical…

Abstract

Purpose

The aim of this paper is to develop network models of an electromagnetic field containing both eddy and displacement currents. The proposed network models provide good physical insight, help understanding of complicated electromagnetic phenomena and aid explanation of methods of analysis of electromagnetic systems.

Design/methodology/approach

The models consist of magnetic and electric networks coupled via sources. The analogy between the finite element method and the loop and nodal formulations of electric circuits is emphasised. The models include networks containing branches associated with element edges (edge networks) or facets (facet networks).

Findings

Methods of determining mmf sources of magnetic networks from loop and branch currents in electric circuits, as well as emf sources in electric networks on the basis of the rate of change of loop and branch fluxes in electric networks, have been carefully considered. The models are general and allow creation of networks of electromagnetic systems containing non‐homogenous materials and multiply‐connected conducting regions.

Originality/value

The presented analogies between the finite element formulation and the equivalent network models not only facilitate understanding of the methods of field analysis but also help to formulate efficient computational algorithms.

Details

COMPEL - The international journal for computation and mathematics in electrical and electronic engineering, vol. 25 no. 3
Type: Research Article
ISSN: 0332-1649

Keywords

Article
Publication date: 17 April 2024

Bingwei Gao, Hongjian Zhao, Wenlong Han and Shilong Xue

This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and…

Abstract

Purpose

This study proposes a predictive neural network model reference decoupling control method for the coupling problem between the leg joints of hydraulic quadruped robots, and verifies its decoupling effect..

Design/methodology/approach

The machine–hydraulic cross-linking coupling is studied as the coupling behavior of the hydraulically driven quadruped robot, and the mechanical dynamics coupling force of the robot system is controlled as the disturbance force of the hydraulic system through the Jacobian matrix transformation. According to the principle of multivariable decoupling, a prediction-based neural network model reference decoupling control method is proposed; each module of the control algorithm is designed one by one, and the stability of the system is analyzed by the Lyapunov stability theorem.

Findings

The simulation and experimental research on the robot joint decoupling control method is carried out, and the prediction-based neural network model reference decoupling control method is compared with the decoupling control method without any decoupling control method. The results show that taking the coupling effect experiment between the hip joint and knee joint as an example, after using the predictive neural network model reference decoupling control method, the phase lag of the hip joint response line was reduced from 20.3° to 14.8°, the amplitude attenuation was reduced from 1.82% to 0.21%, the maximum error of the knee joint coupling line was reduced from 0.67 mm to 0.16 mm and the coupling effect between the hip joint and knee joint was reduced from 1.9% to 0.48%, achieving good decoupling.

Originality/value

The prediction-based neural network model reference decoupling control method proposed in this paper can use the neural network model to predict the next output of the system according to the input and output. Finally, the weights of the neural network are corrected online according to the predicted output and the given reference output, so that the optimization index of the neural network decoupling controller is extremely small, and the purpose of decoupling control is achieved.

Details

Robotic Intelligence and Automation, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 2754-6969

Keywords

Book part
Publication date: 31 May 2016

Carlos Pestana Barros and Peter Wanke

This chapter analyses the efficiency of African airlines using a two-stage network DEA (Data Envelopment Analysis) model. Network DEA models usually take into account the…

Abstract

This chapter analyses the efficiency of African airlines using a two-stage network DEA (Data Envelopment Analysis) model. Network DEA models usually take into account the production process with intermediate inputs derived from the first stage and a second stage that departs from it. This fundamental feature enables one to view the airline production process as a carry-over activity. The analysis covers the 2010–2013 period. The relative efficiency ranks are presented and policy implications are derived.

Details

Airline Efficiency
Type: Book
ISBN: 978-1-78560-940-4

Keywords

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

Article
Publication date: 20 February 2023

Gokhan Agac, Birdogan Baki and Ilker Murat Ar

The purpose of this study is to systematically review the existing literature on the blood supply chain (BSC) from a network design perspective and highlight the research gaps in…

Abstract

Purpose

The purpose of this study is to systematically review the existing literature on the blood supply chain (BSC) from a network design perspective and highlight the research gaps in this area. Moreover, it also aims to pinpoint new research opportunities based on the recent innovative technologies for the BSC network design.

Design/methodology/approach

The study gives a comprehensive systematic review of the BSC network design studies until October 2021. This review was carried out in accordance with preferred reporting items for systematic reviews and meta-analyses (PRISMA). In the literature review, a total of 87 studies were analyzed under six main categories as model structure, application model, solution approach, problem type, the parties of the supply chain and innovative technologies.

Findings

The results of the study present the researchers’ tendencies and preferences when designing their BSC network models.

Research limitations/implications

The study presents a guide for researchers and practitioners on BSC from the point of view of network design and encourages adopting innovative technologies in their BSC network designs.

Originality/value

The study provides a comprehensive systematic review of related studies from the BSC network design perspective and explores research gaps in the collection and distribution processes. Furthermore, it addresses innovative research opportunities by using innovative technologies in the area of BSC network design.

Details

Journal of Modelling in Management, vol. 19 no. 1
Type: Research Article
ISSN: 1746-5664

Keywords

Article
Publication date: 1 January 1992

Andrew Jennings and Hideyuki Higuchi

New methods are needed for accessing very large information services. This paper proposes the use of a user model neural network to allow better access to a news service. The…

Abstract

New methods are needed for accessing very large information services. This paper proposes the use of a user model neural network to allow better access to a news service. The network is constructed on the basis of articles read, and articles marked as rejected. It adapts over time to better represent the user's interests and rank the articles supplied by the news service. Using an augmented keyword search we can also search for articles using keywords in conjunction with the user model neural network. Trials of the system in a USENET news environment show promising results for the use of this approach in information retrieval.

Details

Library Hi Tech, vol. 10 no. 1/2
Type: Research Article
ISSN: 0737-8831

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 network

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.

Article
Publication date: 3 July 2017

Morteza Mahmoudzadeh and Mahmood Alborzi

Iran Nanotechnology Initiative Council could significantly increase the production of scientific articles in the field by imposing ten-year incentive policies so that Iran ranked…

Abstract

Purpose

Iran Nanotechnology Initiative Council could significantly increase the production of scientific articles in the field by imposing ten-year incentive policies so that Iran ranked 7 in this area in the year 2015. But this progress was insufficient to speed up the production and commercialization of nanotechnology products and Iran ranked 44 with a share of 0.03 per cent of nanotechnology production in the world. Therefore, Iran Nanotechnology Initiative Council as a governmental policymaker institution in this area has sought for the policy threefold increase of funding to speed up the production and commercialization of products in this field. But given that the result was not so clear, this research was formed in the form of modeling Iran Nanotechnology Innovation Network and testing various scenarios to increase its efficiency.

Design/methodology/approach

This paper uses simulation framework of innovation networks (SKIN) in an attempt to model the production innovation network in Iran in the field of nanotechnology that can measure the effect of incentive policies in changing the network structure and, consequently, increasing the level and pace of innovation in it. Given that the volume of articles produced in Iranian universities in the field of Nanotechnology had a high speed and volume in comparison with the volume of technical knowledge produced by companies, and because the SKIN framework did not consider the distinction between the two, in the first step, the framework is developed using the model of absorptive capacity of knowledge provided by Cohen and Levinthal (1990) and then the developed model was used to model the Innovation Network.

Findings

Finally, two policies of threefold increase of budget (Scenario 1) and increasing the support for joint projects (with maintaining the current budget level) (Scenario 2) were tested in this model. The social network analysis method was used to analyze the results of the two scenarios, where innovation network topology was compared (as an index to measure the network efficiency) in three states of current status of the network (the baseline scenario), implementing the first and second scenarios of extraction and with each other.

Originality/value

This paper models Iranian Nanotechnology Innovation Network for studying the evolution of the network as a result of executing different supportive scenarios.

Details

Journal of Science and Technology Policy Management, vol. 8 no. 2
Type: Research Article
ISSN: 2053-4620

Keywords

Article
Publication date: 21 November 2008

Luiz Angelo Steffenel, Maxime Martinasso and Denis Trystram

The purpose of this paper is to explain one of the most important collective communication patterns used in scientific applications which is the complete exchange, also called…

Abstract

Purpose

The purpose of this paper is to explain one of the most important collective communication patterns used in scientific applications which is the complete exchange, also called All‐to‐All. Although efficient algorithms have been studied for specific networks, general solutions like those available in well‐known MPI distributions (e.g. the MPI_Alltoall operation) are strongly influenced by the congestion of network resources.

Design/methodology/approach

In this paper we present an integrated approach to model the performance of the All‐to‐All collective operation, which consists in identifying a contention signature that characterizes a given network environment, using it to augment a contention‐free communication model.

Findings

This approach, assessed by experimental results, allows an accurate prediction of the performance of the All‐to‐All operation over different network architectures with a small overhead.

Practical implications

The paper discusses the problem of network contention in a grid environment, studying some strategies to minimize the impact of contention on the performance of an All‐to‐All operation.

Originality/value

The approach used, assessed by experimental results, allows an accurate prediction of the performance of the All‐to‐All operation over different network architectures with a small overhead. Also discussed is the problem of network contention in a grid environment and some strategies to minimize the impact of contention on the performance of an All‐to‐All operation.

Details

International Journal of Pervasive Computing and Communications, vol. 4 no. 4
Type: Research Article
ISSN: 1742-7371

Keywords

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