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Article
Publication date: 4 January 2013

Francisco Chinesta, Adrien Leygue, Marianne Beringhier, Linh Tuan Nguyen, Jean‐Claude Grandidier, Bernhard Schrefler and Francisco Pesavento

The purpose of this paper is to solve non‐linear parametric thermal models defined in degenerated geometries, such as plate and shell geometries.

Abstract

Purpose

The purpose of this paper is to solve non‐linear parametric thermal models defined in degenerated geometries, such as plate and shell geometries.

Design/methodology/approach

The work presented in this paper is based in a combination of the proper generalized decomposition (PGD) that proceeds to a separated representation of the involved fields and advanced non‐linear solvers. A particular emphasis is put on the asymptotic numerical method.

Findings

The authors demonstrate that this approach is valid for computing the solution of challenging thermal models and parametric models.

Originality/value

This is the first time that PGD is combined with advanced non‐linear solvers in the context of non‐linear transient parametric thermal models.

Details

International Journal of Numerical Methods for Heat & Fluid Flow, vol. 23 no. 1
Type: Research Article
ISSN: 0961-5539

Keywords

Article
Publication date: 17 September 2008

Randolph C. Rach

To provide a new proof of convergence of the Adomian decomposition series for solving nonlinear ordinary and partial differential equations based upon a thorough examination of…

1377

Abstract

Purpose

To provide a new proof of convergence of the Adomian decomposition series for solving nonlinear ordinary and partial differential equations based upon a thorough examination of the historical milieu preceding the Adomian decomposition method.

Design/methodology/approach

Develops a theoretical background of the Adomian decomposition method under the auspices of the Cauchy‐Kovalevskaya theorem of existence and uniqueness for solution of differential equations. Beginning from the concepts of a parametrized Taylor expansion series as previously introduced in the Murray‐Miller theorem based on analytic parameters, and the Banach‐space analog of the Taylor expansion series about a function instead of a constant as briefly discussed by Cherruault et al., the Adomian decompositions series and the series of Adomian polynomials are found to be a uniformly convergent series of analytic functions for the solution u and the nonlinear composite function f(u). To derive the unifying formula for the family of classes of Adomian polynomials, the author develops the novel notion of a sequence of parametrized partial sums as defined by truncation operators, acting upon infinite series, which induce these parametrized sums for simple discard rules and appropriate decomposition parameters. Thus, the defining algorithm of the Adomian polynomials is the difference of these consecutive parametrized partial sums.

Findings

The four classes of Adomian polynomials are shown to belong to a common family of decomposition series, which admit solution by recursion, and are derived from one unifying formula. The series of Adomian polynomials and hence the solution as computed as an Adomian decomposition series are shown to be uniformly convergent. Furthermore, the limiting value of the mth Adomian polynomial approaches zero as the index m approaches infinity for the prerequisites of the Cauchy‐Kovalevskaya theorem. The novel truncation operators as governed by discard rules are analogous to an ideal low‐pass filter, where the decomposition parameters represent the cut‐off frequency for rearranging a uniformly convergent series so as to induce the parametrized partial sums.

Originality/value

This paper unifies the notion of the family of Adomian polynomials for solving nonlinear differential equations. Further it presents the new notion of parametrized partial sums as a tool for rearranging a uniformly convergent series. It offers a deeper understanding of the elegant and powerful Adomian decomposition method for solving nonlinear ordinary and partial differential equations, which are of paramount importance in modeling natural phenomena and man‐made device performance parameters.

Details

Kybernetes, vol. 37 no. 7
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 June 2003

R. Brahme and A. Mahdavi

It is important to provide building performance feedback to the designer as early as possible in the design process. However, many aspects of building performance are…

Abstract

It is important to provide building performance feedback to the designer as early as possible in the design process. However, many aspects of building performance are significantly affected by the design of the building’s technical systems (e.g., heating, airconditioning), which are typically configured in detail only in the later stages of design. The challenge is thus to find a method to use detailed simulation tools even during the early stages of design when values for many of the variables for the building’s technical systems are not yet available. In this paper, we demonstrate how this problem can be partially solved by use of differential representation for building and technical system, homology‐based automatic mapping of relevant information from the building to the technical system representation, and generative design agents which, with a minimal user‐input, can design and model the technical system. We conclude the paper with illustrative examples of detailed performance analysis of complex buildings and their heating, ventilation, and air‐conditioning systems, performed in early stages of design.

Details

Construction Innovation, vol. 3 no. 2
Type: Research Article
ISSN: 1471-4175

Keywords

Article
Publication date: 6 May 2021

Tim Chen, N. Kapronand, C.Y. Hsieh and J. Cy Chen

To guarantee the asymptotic stability of discrete-time nonlinear systems, this paper aims to propose an evolved bat algorithm fuzzy neural network (NN) controller algorithm.

Abstract

Purpose

To guarantee the asymptotic stability of discrete-time nonlinear systems, this paper aims to propose an evolved bat algorithm fuzzy neural network (NN) controller algorithm.

Design/methodology/approach

In evolved fuzzy NN modeling, the NN model and linear differential inclusion representation are established for the arbitrary nonlinear dynamics. The control problems of the Fisher equation and a temperature cooling fin for high-speed aerospace vehicles will be described and demonstrated. The signal auxiliary controlled system is represented for the nonlinear parabolic partial differential equation (PDE) systems and the criterion of stability is derived via the Lyapunov function in terms of linear matrix inequalities.

Findings

This representation is constructed by sector nonlinearity, which converts the nonlinear model to a multiple rule base for the linear model and a new sufficient condition to guarantee the asymptotic stability.

Originality/value

This study also injects high frequency as an auxiliary and the control performance to stabilize the nonlinear high-speed aerospace vehicle system.

Details

Aircraft Engineering and Aerospace Technology, vol. 93 no. 4
Type: Research Article
ISSN: 1748-8842

Keywords

Abstract

Details

Dynamic General Equilibrium Modelling for Forecasting and Policy: A Practical Guide and Documentation of MONASH
Type: Book
ISBN: 978-0-44451-260-4

Article
Publication date: 16 April 2018

Behzad Nemati Saray and Jalil Manafian

The purpose of this study is an application of the multi-wavelets Galerkin method to delay differential equations with vanishing delay known as Pantograph equation.

Abstract

Purpose

The purpose of this study is an application of the multi-wavelets Galerkin method to delay differential equations with vanishing delay known as Pantograph equation.

Design/methodology/approach

The method consists of expanding the required approximate solution at the elements of the Alpert multi-wavelets. Using the operational matrices of integration and wavelet transform matrix, the authors reduce the problem to a set of algebraic equations.

Findings

Because of the large size of the system, thresholding is used to obtain a new sparse system, and then this new system is solved to reduce the computational effort and related computer run time. The authors demonstrate that the solutions may be efficiently represented in a multi-wavelets basis because of flexible vanishing moments property of this type of multi-wavelets.

Originality/value

The L2 convergence of the scheme for the proposed equation has been investigated. A series of numerical tests is provided to demonstrate the validity and applicability of the technique.

Details

Engineering Computations, vol. 35 no. 2
Type: Research Article
ISSN: 0264-4401

Keywords

Book part
Publication date: 28 May 2021

Alina Korn

Purpose: This study is concerned with media representation of crime in the Israeli press. It examines the pattern of offenses reported in two daily newspapers of seemingly…

Abstract

Purpose: This study is concerned with media representation of crime in the Israeli press. It examines the pattern of offenses reported in two daily newspapers of seemingly different characteristics, the “elitist” Haaretz and the “popular” Israel Hayom. Methodology/approach: Crime reports appeared in the news pages during November 2016 were content analyzed in both newspapers by using a coding scheme, which operationalized several variables relating to type of crime, characteristics of offenders and victims, and court proceedings. Findings: Violent and sex offenses featured disproportionately in the news reports in both newspapers, while conventional property offenses were under-reported relative to their prevalence in official crime statistics. In terms of the characteristics of offenders and victims, the vast majority of offenders portrayed in crime stories were adult Jewish males. Women were more likely to appear as victims of crime rather than perpetrators, and more likely to appear as victims of sex offenses rather than other offenses. Research limitations: This study was based on an analysis of crime stories which appeared in two newspapers during one-month period of time. Future research should extend the sample size and collect data from a longer period of time and from additional media outlets. Originality/value: Media coverage of crime stories has not yet been researched in Israel. Beyond the interest in the Israeli case or the potential contribution to comparative global knowledge, the value of the study may lie in expanding the lens of scholarship of media’s construction of crime.

Details

Mass Mediated Representations of Crime and Criminality
Type: Book
ISBN: 978-1-80043-759-3

Keywords

Abstract

Details

Freight Transport Modelling
Type: Book
ISBN: 978-1-78190-286-8

Article
Publication date: 2 October 2018

Michael Francis Aiello

Prior research established several important influences on the representation of women in policing, using a variety of secondary and primary data. The purpose of this paper is to…

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Abstract

Purpose

Prior research established several important influences on the representation of women in policing, using a variety of secondary and primary data. The purpose of this paper is to examine how experimental manipulation of online recruitment materials impacts potential applicants.

Design/methodology/approach

The study relied on a census of 11 criminal justice courses taught at a public university, asking students to respond to an experimental vignette instrument (n=174). The 3×2 experimental vignette involved manipulation of two variables: the identification of recruits with diversity language (“individuals,” “women and men” or “a diverse group of individuals”) and mention or absence of discussion of physical fitness requirements.

Findings

Results largely run counter to prior research concerning women in policing, with women actually indicating increased probability of providing their contact information when encountering vignettes with physical fitness requirements.

Originality/value

This study demonstrates that small manipulations of recruitment content can have significant and gendered impact on potential applicants. This paper provides a foundation for empirical study of how changes in online recruitment materials impact a variety of relevant outcomes relating to applicant behaviors.

Details

Policing: An International Journal, vol. 42 no. 3
Type: Research Article
ISSN: 1363-951X

Keywords

Article
Publication date: 23 September 2022

Li Chen, Sheng-Qun Chen and Long-Hao Yang

This paper aims to solve the major assessment problem in matching the satisfaction of psychological gratification and mission accomplishment pertaining to volunteers with the…

Abstract

Purpose

This paper aims to solve the major assessment problem in matching the satisfaction of psychological gratification and mission accomplishment pertaining to volunteers with the disaster rescue and recovery tasks.

Design/methodology/approach

An extended belief rule-based (EBRB) method is applied with the method's input and output parameters classified based on expert knowledge and data from literature. These parameters include volunteer self-satisfaction, experience, peer-recognition, and cooperation. First, the model parameters are set; then, the parameters are optimized through data envelopment analysis (DEA) and differential evolution (DE) algorithm. Finally, a numerical mountain rescue example and comparative analysis between with-DEA and without-DEA are presented to demonstrate the efficiency of the proposed method. The proposed model is suitable for a two-way matching evaluation between rescue tasks and volunteers.

Findings

Disasters are unexpected events in which emergency rescue is crucial to human survival. When a disaster occurs, volunteers provide crucial assistance to official rescue teams. This paper finds that decision-makers have a better understanding of two-sided match objects through bilateral feedback over time. With the changing of the matching preference information between rescue tasks and volunteers, the satisfaction of volunteer's psychological gratification and mission accomplishment are also constantly changing. Therefore, considering matching preference information and satisfaction at two-sided match objects simultaneously is necessary to get reasonable target values of matching results for rescue tasks and volunteers.

Originality/value

Based on the authors' novel EBRB method, a matching assessment model is constructed, with two-sided matching of volunteers to rescue tasks. This method will provide matching suggestions in the field of emergency dispatch and contribute to the assessment of emergency plans around the world.

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