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Article
Publication date: 1 June 2004

Martin Zwick and Michael S. Johnson

Reconstructability analysis (RA) is a method for detecting and analyzing the structure of multivariate categorical data. While Jones and his colleagues extended the original…

Abstract

Reconstructability analysis (RA) is a method for detecting and analyzing the structure of multivariate categorical data. While Jones and his colleagues extended the original variable‐based formulation of RA to encompass models defined in terms of system states, their focus was the analysis and approximation of real‐valued functions. In this paper, we separate two ideas that Jones had merged together: the “g to k” transformation and state‐based modeling. We relate the idea of state‐based modeling to established variable‐based RA concepts and methods, including structure lattices, search strategies, metrics of model quality, and the statistical evaluation of model fit for analyses based on sample data. We also discuss the interpretation of state‐based modeling results for both neutral and directed systems, and address the practical question of how state‐based approaches can be used in conjunction with established variable‐based methods.

Details

Kybernetes, vol. 33 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 2 February 2015

Edilson M. Assis, Ernesto P. Borges, Silvio A.B. Vieira de Melo and Leizer Schnitman

The purpose of this paper is to compare four life data models, namely the exponential and the Weibull models, and their corresponding generalized versions, q-exponential and q

Abstract

Purpose

The purpose of this paper is to compare four life data models, namely the exponential and the Weibull models, and their corresponding generalized versions, q-exponential and q-Weibull models, by means of one practical application.

Design/methodology/approach

Application of the models to a practical example (a welding station), with estimation of parameters by the use of the least squares method, and the Akaike Information Criterion (AIC).

Findings

The data of the example considered in this paper is divided into three regimes, decreasing, constant and increasing failure rate, and the q-Weibull model describes the bathtub curve displayed by the data with a single set of parameters.

Practical implications

The simplicity and flexibility of the q-Weibull model may be very useful for practitioners of reliability analysis, and its benefits surpasses the inconvenience of the additional parameter, as AIC shows.

Originality/value

The q-Weibull model is compared in detail with other three models, through the analysis of one example that clearly exhibits a bathtub curve, and it is shown that it can describe the whole time range with a single set of parameters.

Details

International Journal of Quality & Reliability Management, vol. 32 no. 2
Type: Research Article
ISSN: 0265-671X

Keywords

Article
Publication date: 1 April 1996

Ray Perry

Automating warehouse operations can be a very alluring proposition. However, it is vital that a decision to progress with such substantial investment is taken only after the…

772

Abstract

Automating warehouse operations can be a very alluring proposition. However, it is vital that a decision to progress with such substantial investment is taken only after the deliverable benefits are thoroughly understood. This is especially important when the business environment is changing rapidly. Describes the approach taken by B&Q to decide on the appropriate level of automation; explains how, through a process of establishing good performance through manual processes, it has created a sound base against which it can evaluate automation, and how its new supply chain strategy has exposed further opportunities to improve business performance. Also describes how B&Q Distribution has renewed its focus on serving the customer (the B&Q retail store), and how this experience has affected the automation project. Finally, covers B&Q’s approach to supplier selection.

Details

Logistics Information Management, vol. 9 no. 2
Type: Research Article
ISSN: 0957-6053

Keywords

Article
Publication date: 1 June 2004

Martin Zwick

Fourier methods used in two‐ and three‐dimensional image reconstruction can be used also in reconstructability analysis (RA). These methods maximize a variance‐type measure…

Abstract

Fourier methods used in two‐ and three‐dimensional image reconstruction can be used also in reconstructability analysis (RA). These methods maximize a variance‐type measure instead of information‐theoretic uncertainty, but the two measures are roughly collinear and the Fourier approach yields results close to that of standard RA. The Fourier method, however, does not require iterative calculations for models with loops. Moreover, the error in Fourier RA models can be assessed without actually generating the full probability distributions of the models; calculations scale with the size of the data rather than the state space. State‐based modeling using the Fourier approach is also readily implemented. Fourier methods may thus enhance the power of RA for data analysis and data mining.

Details

Kybernetes, vol. 33 no. 5/6
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 13 September 2011

S. Spitans and A. Jakovičs

The purpose of this paper is to compare k‐ω shear‐stress transport (SST) and large eddy simulation (LES) turbulence model application effect on numerical computation of flow…

Abstract

Purpose

The purpose of this paper is to compare k‐ω shear‐stress transport (SST) and large eddy simulation (LES) turbulence model application effect on numerical computation of flow pattern and heat exchange characteristics through the neutron beam window region for European spallation source setup model.

Design/methodology/approach

Transient hydrodynamic and thermal calculations with appropriate heat sources are performed using both turbulence models and typical discrepancies in flow and thermal patterns are discussed, as well as, simulation results are qualitatively compared with experimental data for heat transfer coefficient distribution α at the window surface.

Findings

Contribution of greater k‐energy field obtained with LES calculation leads to prediction of more intensive heat transfer in comparison to k‐ω SST.

Originality/value

The paper illustrates discrepancies of thermal patterns caused by application of k‐ω SST and LES turbulent models.

Details

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

Keywords

Article
Publication date: 1 December 1998

Y.K. Chan, P. Gaffney, K. Neailey and W.H. Ip

In today’s public transport market where competition is keener than ever, railway operators are in desperate need of a customised total quality management approach to enhance…

1579

Abstract

In today’s public transport market where competition is keener than ever, railway operators are in desperate need of a customised total quality management approach to enhance performance and outcompete their counterparts. This paper outlines the work related to the establishment and implementation of such a total management approach, an integrated management system evolved from the ISO 9000‐based quality management system, in the Mass Transit Railway Corporation (MTR Corporation), Hong Kong, and how this system serves to enhance the corporation’s competitiveness by successfully addressing its rapidly changing needs.

Details

The TQM Magazine, vol. 10 no. 6
Type: Research Article
ISSN: 0954-478X

Keywords

Article
Publication date: 14 October 2014

Helen Xiaohui Bao, Helen Hui Huang, Yu-Lieh Huang and Pin-te Lin

– The purpose of this paper is to investigate the volatility clustering in the return of land markets through both theoretical and empirical approaches.

339

Abstract

Purpose

The purpose of this paper is to investigate the volatility clustering in the return of land markets through both theoretical and empirical approaches.

Design/methodology/approach

Using extensive monthly panel data at the provincial level from 1986 to 2013, the authors identify the existence of time-correlated and time-varying returns in Canadian land markets.

Findings

Consistent with the proposed theory, volatility clustering in land markets tends to be observed in more populated areas.

Originality/value

The result has significant implications for portfolio management, economic theory and government policy by revealing the systematic pattern of volatility clustering in land markets.

Details

Property Management, vol. 32 no. 5
Type: Research Article
ISSN: 0263-7472

Keywords

Article
Publication date: 19 October 2023

Moussa Sigue, Désiré Drabo, Soumaïla Woni, Gnanderman Sirpe and Aminata Ouedraogo

This paper aims to assess the short- and long-run effects of the interaction between institutional quality and financial development (FD) on the competitiveness of the WAEMU…

Abstract

Purpose

This paper aims to assess the short- and long-run effects of the interaction between institutional quality and financial development (FD) on the competitiveness of the WAEMU economy over the period 2007–2018.

Design/methodology/approach

The methodology consisted of cross-referencing a synthetic indicator of FD with indicators of institutional quality and then estimating an auto regressive distributed lag model.

Findings

The results of the pooled mean group and dynamic fixed effect estimation show a positive and significant impact of this interaction on the competitiveness of the economy in the long run. In the short run, the results are quite similar to those in the long run for the direct effects but different for the crosses. Also, the analysis of country specificity shows that the results are similar to those in the short run since the interaction between FD and institutional quality (political stability and government effectiveness) negatively affects the competitiveness of Burkina Faso, Ivory Coast and Mali, and positively affects the competitiveness of Benin and Senegal.

Social implications

These results suggest the need for effective policies to improve the quality of institutions to enhance the mobilization of financial resources through FD to ensure the competitiveness of economies. Improving the quality of the political and institutional environment is a prerequisite for economic competitiveness.

Originality/value

The paper is in line with the New Institutional Economics that developed in the 1970s. This referential framework is a heterogeneous body of work that encompasses works whose common point is the determination of the role of institutions in economic coordination. Unlike previous studies, which have focused on the contribution of the interaction between institutional quality variables and FD on economic growth, this paper analyzes the effects of this interaction on economic competitiveness. It, therefore, constitutes a contribution to this literature and aims primarily to fill this gap.

Details

Competitiveness Review: An International Business Journal , vol. 34 no. 4
Type: Research Article
ISSN: 1059-5422

Keywords

Article
Publication date: 28 March 2023

Abdul-Majid Wazwaz, Haifa A. Alyousef and Samir El-Tantawy

This study aims to propose an extended (3 + 1)-dimensional integrable Kadomtsev–Petviashvili equation characterized by adding three new linear terms.

Abstract

Purpose

This study aims to propose an extended (3 + 1)-dimensional integrable Kadomtsev–Petviashvili equation characterized by adding three new linear terms.

Design/methodology/approach

This study formally uses Painlevé test to confirm the integrability of the new system.

Findings

The Painlevé analysis shows that the compatibility condition for integrability does not die away by adding three new linear terms with distinct coefficients.

Research limitations/implications

This study uses the Hirota's bilinear method to explore multiple soliton solutions where phase shifts and phase variable are explored.

Practical implications

This study also furnishes a class of lump solutions (LSs), which are rationally localized in all directions in space, using distinct values of the parameters via using the positive quadratic function method.

Social implications

This study also shows the power of the simplified Hirota’s method in handling integrable equations.

Originality/value

This paper introduces an original work with newly developed Painlevé integrable model and shows new useful findings.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 33 no. 7
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 25 February 2014

Jiuchang Wei, Bing Bu, Xiumei Guo and Margaret Gollagher

The strength of ties between individuals influences the speed and spread of crisis information dissemination (CID). By constructing networks of strong and weak ties, this paper…

1026

Abstract

Purpose

The strength of ties between individuals influences the speed and spread of crisis information dissemination (CID). By constructing networks of strong and weak ties, this paper aims to innovatively explore the impacts of strong and weak ties on the CID at the macro level.

Design/methodology/approach

To better understand the rules of CID in different kinds of social networks, this paper constructs a CID model based on the strength of ties in social networks and cellular automation, using simulations of CID speed and spread in an entire network, strong tie network and weak tie network generated by MATLAB.

Findings

As the article's major theoretical contribution, the results demonstrate that CID is more efficient in a network of weak ties than in a network of strong ties, and that the spread of CID has a positive correlation with the believability of the information disseminated and the dissemination tendency coefficient. Furthermore, the difference of dissemination speeds between strong and weak tie networks varies regularly with information believability and the dissemination tendency coefficient.

Originality/value

This study provides more effective public mechanisms for rapidly evaluating the believability of crisis information and responding to crises in real time. The findings also have some valuable implications for government agencies to improve the efficiency and effect of CID.

Details

Kybernetes, vol. 43 no. 2
Type: Research Article
ISSN: 0368-492X

Keywords

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