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Article
Publication date: 1 December 2004

A. Deraemaeker, P. Ladevèze and T. Romeuf

In this paper, we discuss the application of the constitutive relation error (CRE) to model updating and validation in the context of uncertain measurements. First, a parallel is…

Abstract

In this paper, we discuss the application of the constitutive relation error (CRE) to model updating and validation in the context of uncertain measurements. First, a parallel is drawn between the CRE method and a general theory for inverse problems proposed by Tarantola. Then, an extension of the classical CRE method considering uncertain measurements is proposed. It is shown that the proposed mechanics‐based approach for model validation is very effective in filtering noise in the experimental data. The method is applied to an industrial structure, the SYLDA5, which is a satellite support for Ariane5. The results demonstrate the robustness of the method in actual industrial situations.

Details

Engineering Computations, vol. 21 no. 8
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 20 July 2010

A. Caignot, P. Ladevèze, D. Néron and J.‐F. Durand

The purpose of this paper is to propose a virtual testing strategy in order to predict damping due to the joints which are present in the ARIANE 5 launcher.

Abstract

Purpose

The purpose of this paper is to propose a virtual testing strategy in order to predict damping due to the joints which are present in the ARIANE 5 launcher.

Design/methodology/approach

Since engineering finite element codes do not give satisfactory results, either because they are too slow or because they cannot calculate dissipation accurately, a new computational tool is introduced based on the LArge Time INcrement (LATIN) method in its multiscale version.

Findings

The capabilities of the new strategy are illustrated on one of the joints of ARIANE 5. The damping predicted virtually is compared to experimental results, and the approach appears promising.

Originality/value

The tool which has been developed gives access to calculations which were previously unaffordable with standard computational codes, which may improve the design process of launchers. The code is transferred into ASTRIUM‐ST, where it is being used to build a database of dissipations in the joints of the ARIANE 5 launcher.

Details

Engineering Computations, vol. 27 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 3 July 2017

Saurabh Prabhu, Sez Atamturktur and Scott Cogan

This paper aims to focus on the assessment of the ability of computer models with imperfect functional forms and uncertain input parameters to represent reality.

109

Abstract

Purpose

This paper aims to focus on the assessment of the ability of computer models with imperfect functional forms and uncertain input parameters to represent reality.

Design/methodology/approach

In this assessment, both the agreement between a model’s predictions and available experiments and the robustness of this agreement to uncertainty have been evaluated. The concept of satisfying boundaries to represent input parameter sets that yield model predictions with acceptable fidelity to observed experiments has been introduced.

Findings

Satisfying boundaries provide several useful indicators for model assessment, and when calculated for varying fidelity thresholds and input parameter uncertainties, reveal the trade-off between the robustness to uncertainty in model parameters, the threshold for satisfactory fidelity and the probability of satisfying the given fidelity threshold. Using a controlled case-study example, important modeling decisions such as acceptable level of uncertainty, fidelity requirements and resource allocation for additional experiments are shown.

Originality/value

Traditional methods of model assessment are solely based on fidelity to experiments, leading to a single parameter set that is considered fidelity-optimal, which essentially represents the values which yield the optimal compensation between various sources of errors and uncertainties. Rather than maximizing fidelity, this study advocates for basing model assessment on the model’s ability to satisfy a required fidelity (or error tolerance). Evaluating the trade-off between error tolerance, parameter uncertainty and probability of satisfying this predefined error threshold provides us with a powerful tool for model assessment and resource allocation.

Details

Engineering Computations, vol. 34 no. 5
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 1 August 2002

Peter R. Senn

This is an article about the possible lessons for academic freedom that Dühring’s expulsion from the University of Berlin might have for us today. It begins with a brief…

Abstract

This is an article about the possible lessons for academic freedom that Dühring’s expulsion from the University of Berlin might have for us today. It begins with a brief discussion of his strange fate in the English language literature in contrast with his high position in the history of economic thought. It is no surprise that questions of the denial of academic freedom have long been discussed. The remainder of the article is devoted to a discussion of academic freedom since his time and the possible lessons these developments might have for us today. The most important of these is the ancient truism – academic freedom is always under attack from many sides and must be vigorously defended.

Details

Journal of Economic Studies, vol. 29 no. 4/5
Type: Research Article
ISSN: 0144-3585

Keywords

Article
Publication date: 1 August 1999

Peter R. Senn

The focus of this paper is the economic theory of the plans for the European Monetary Union. Part 1 demonstrates that economists, bankers and policy makers know very little about…

5434

Abstract

The focus of this paper is the economic theory of the plans for the European Monetary Union. Part 1 demonstrates that economists, bankers and policy makers know very little about monetary policy. Part 2 explains the errors of the common practice of defining money by its functions. Because any monetary policy must rest on a definition of money it seems reasonable to conclude that a flawed definition might lead to problems with monetary policy. Part 3 applies this insight to the plans for a common currency in Europe. Because of uncertainties about the timing and details of the implementation, some important considerations are necessarily speculative. They are relegated to appendices. Appendix 1 comments on the timing and authorship and responsibility for the official reports with their unspecified authors. Appendix 2 supplies some grounds for doubting the ultimate durability of the European Monetary Union focusing on reasons that are historical, economic and pragmatic. Because the entire movement is driven by politics, not economics, Appendix 3 considers some of the relevant political issues. The conclusions summarize and speculate on possible reasons for successful outcomes.

Details

Journal of Economic Studies, vol. 26 no. 4/5
Type: Research Article
ISSN: 0144-3585

Keywords

Book part
Publication date: 25 June 2010

Daniele Besomi

Business cycle theory is normally described as having evolved out of a previous tradition of writers focusing exclusively on crises. In this account, the turning point is seen as…

Abstract

Business cycle theory is normally described as having evolved out of a previous tradition of writers focusing exclusively on crises. In this account, the turning point is seen as residing in Clément Juglar's contribution on commercial crises and their periodicity. It is well known that the champion of this view is Schumpeter, who propagated it on several occasions. The same author, however, pointed to a number of other writers who, before and at the same time as Juglar, stressed one or another of the aspects for which Juglar is credited primacy, including the recognition of periodicity and the identification of endogenous elements enabling the recognition of crises as a self-generating phenomenon. There is indeed a vast literature, both primary and secondary, relating to the debates on crises and fluctuations around the middle of the nineteenth century, from which it is apparent that Juglar's book Des Crises Commerciales et de leur Retour Périodique en France, en Angleterre et aux États-Unis (originally published in 1862 and very much revised and enlarged in 1889) did not come out of the blue but was one of the products of an intellectual climate inducing the thinking of crises not as unrelated events but as part of a more complex phenomenon consisting of recurring crises related to the development of the commercial world – an interpretation corroborated by the almost regular occurrence of crises at about 10-year intervals.

Details

A Research Annual
Type: Book
ISBN: 978-0-85724-060-6

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