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Article
Publication date: 19 July 2019

Tim Chen, Safiullahand Khurram and CYJ Cheng

This paper aims to deal with the problem of the global stabilization for a class of tension leg platform (TLP) nonlinear control systems.

Abstract

Purpose

This paper aims to deal with the problem of the global stabilization for a class of tension leg platform (TLP) nonlinear control systems.

Design/methodology/approach

It is well-known that, in general, the global asymptotic stability of the TLP subsystems does not imply the global asymptotic stability of the composite closed-loop system.

Findings

An effective approach is proposed to control chaos via the combination of fuzzy controllers, fuzzy observers and dithers.

Research limitations/implications

If a fuzzy controller and a fuzzy observer cannot stabilize the chaotic system, a dither, as an auxiliary of the controller and the observer, is simultaneously introduced to asymptotically stabilize the chaotic system.

Originality/value

Thus, the behavior of the closed-loop dithered chaotic system can be rigorously predicted by establishing that of the closed-loop fuzzy relaxed system.

Details

Engineering Computations, vol. 36 no. 7
Type: Research Article
ISSN: 0264-4401

Keywords

Article
Publication date: 27 January 2022

ZY Chen, Yahui Meng, Ruei-Yuan Wang and Timothy Chen

To prove the effectiveness of the proposed design method, this study aims to propose the Fisher equation and temperature cooling fins that control high-speed aerospace vehicles.

Abstract

Purpose

To prove the effectiveness of the proposed design method, this study aims to propose the Fisher equation and temperature cooling fins that control high-speed aerospace vehicles.

Design/methodology/approach

A new approach whereby the control of aerospace vehicles can be achieved by fuzzy controller and appropriate Navier–Stokes equations in this article. The design of the controller based on models of Navier–Stokes equations simplified complex mathematical simulations and approximations.

Findings

If the fuzzy controller cannot stabilize the system, the Navier–Stokes fuzzy function is injected into the system as a controller tool, and the system is asymptotically stabilized by adjusting the fuzzy parameters.

Originality/value

The simulation results show that if the tuning frequency is high enough, the fuzzy controller and fuzzy observer can create chaotic movements by adjusting the dither amplitude appropriately. The demonstration of the Fisher equation and the temperature-cooled fin control problem for high-speed aerospace vehicles has displayed the benefits of combining fuzzy control with the Navier–Stokes equation.

Details

Aircraft Engineering and Aerospace Technology, vol. 94 no. 3
Type: Research Article
ISSN: 1748-8842

Keywords

Article
Publication date: 1 March 1999

K.H. Spencer Pickett

Using the backdrop of an (apparently) extended visit to the West Indies, analogies with key concerns of internal audit are drawn. An unusual and refreshing way of exploring the…

39986

Abstract

Using the backdrop of an (apparently) extended visit to the West Indies, analogies with key concerns of internal audit are drawn. An unusual and refreshing way of exploring the main themes ‐ a discussion between Bill and Jack on tour in the islands ‐ forms the debate. Explores the concepts of control, necessary procedures, fraud and corruption, supporting systems, creativity and chaos, and building a corporate control facility.

Details

Management Decision, vol. 37 no. 2
Type: Research Article
ISSN: 0025-1747

Keywords

Article
Publication date: 1 June 1998

K.H. Spencer Pickett

Using the backdrop of an (apparently) extended visit to the West Indies, analogies with key concerns of internal audit are drawn. An unusual and refreshing way of exploring the…

38379

Abstract

Using the backdrop of an (apparently) extended visit to the West Indies, analogies with key concerns of internal audit are drawn. An unusual and refreshing way of exploring the main themes ‐ a discussion between Bill and Jack on tour in the islands ‐ forms the debate. Explores the concepts of control, necessary procedures, fraud and corruption, supporting systems, creativity and chaos, and building a corporate control facility.

Details

Managerial Auditing Journal, vol. 13 no. 4/5
Type: Research Article
ISSN: 0268-6902

Keywords

Article
Publication date: 14 May 2020

Moshe Szweizer

The purpose of this study is to provide a chaos theory-based framework, which can be used to model commercial property market dynamics.

Abstract

Purpose

The purpose of this study is to provide a chaos theory-based framework, which can be used to model commercial property market dynamics.

Design/methodology/approach

The paper is presented in two parts. In the first, rigorous mathematical reasoning is entertained, so to derive an attractor describing a set of feedback formulae. In the second part, the attractor definition is used to model the Auckland commercial office market. The model is exposed through a set of seven scenarios allowing for analysis of the market behaviour under various exogenously imposed conditions.

Findings

The general behaviour of the model is in agreement with the commercial property market conduct observed in Auckland. The model provides information related to the market turning points and allows for an explanation of some intricate market dynamics. These include the anatomy of a market peak and its response to the liquidity oversupply.

Practical implications

The model may be used to expand our understanding of the market performance under various exogenically imposed conditions, which allows for planning of market interventions in a more refined manner.

Originality/value

The paper is original, in the way the chaos theory is applied to the property markets modelling and allows for expanding the understanding of the market behaviour.

Details

Journal of Property Investment & Finance, vol. 38 no. 6
Type: Research Article
ISSN: 1463-578X

Keywords

Article
Publication date: 1 December 2002

Stanley Krippner and Allan Combs

This systems model of dreaming consciousness examines the self‐organizing properties of the sleeping brain, offering a step towards reconciling brain‐based and content‐based…

576

Abstract

This systems model of dreaming consciousness examines the self‐organizing properties of the sleeping brain, offering a step towards reconciling brain‐based and content‐based attempts to understand the nature of dreaming. The brain can be understood as a complex self‐organizing system that, in dreaming, responds to subtle influences such as residual feelings and memories. The hyper‐responsiveness of the brain during dreaming is viewed in terms of the tendency of complex chaotic‐like systems to respond to small variations in initial conditions and to the amplification of subtle emotional and cognitive signals through the mechanism of stochastic resonance, all in combination with psychophysiological changes in the brain during both slow wave and rapid eye movement (REM) dreaming. These changes include the active inhibition of extroceptive stimulation and, especially in REM sleep, alterations in the brain's dominant neuromodulatory systems, bombardment of the visual cortex with bursts of PGO activity, increases in limbic system activity, and a reduction of activity in the prefrontal regions.

Details

Kybernetes, vol. 31 no. 9/10
Type: Research Article
ISSN: 0368-492X

Keywords

Article
Publication date: 1 August 2006

Amir M. Sharif and Zahir Irani

Noting the scarcity of complexity techniques applied to modelling social systems, this paper attempts to formulate a conceptual model of decision‐making behaviour within the…

2363

Abstract

Purpose

Noting the scarcity of complexity techniques applied to modelling social systems, this paper attempts to formulate a conceptual model of decision‐making behaviour within the information systems evaluation (ISE) task, against the backdrop of complexity theory.

Design/methodology/approach

Complexity theory places an emphasis on addressing how dynamic non‐linear systems can be represented and modelled utilising computational tools and techniques to draw out inherent system dynamics. In doing so, the use of fuzzy cognitive mapping (FCM) and morphological analysis (MA) (hence a fuzzy‐morphological approach), is applied to empirical case study data, to elucidate the inherent behavioural and systems issues involved in ISE decision making within a British manufacturing organisation.

Findings

The paper presents results of applying a combined FCM and MA approach to modelling complexity within management decision making in the ISE task: both in terms of a cognitive map of the key decision criteria; a matrix of constraint criteria; and a synthesised model that provides an indication of the linkages between technology management factors and organisational imperatives and goals. These findings show the usefulness of viewing the topic in complexity science terms (emergent behaviour, non‐linearity and chaotic response).

Research limitations/implications

This research is limited in applying the given technique to a single case study organisation in the UK manufacturing sector, where the sample size is limited. Since this is the first time that such a combined MA‐FCM technique has been used in this field known to the authors, future research needs to validate and explore the implications of this approach in a wider context (multiple organisations and viewpoints).

Practical implications

The paper highlights the need for those involved in analysing managerial decision making to include aspects of complexity theory in their evaluations – namely uncovering inherent inter‐relationships that may exist between stakeholders, processes and systems. In doing so, expanding the manager's understanding of how to achieve congruence between driving forces and factors, which may exhibit non‐linear, chaotic or feedback behaviour.

Originality/value

The given research brings together both artificial intelligence and operational research techniques, applied in the socio‐technical milieu of information systems evaluation, within the context of complexity theory, in order to describe the rich detail within the ISE decision‐making task.

Details

Management Decision, vol. 44 no. 7
Type: Research Article
ISSN: 0025-1747

Keywords

Article
Publication date: 1 November 2006

Orlando Gomes

The purpose of this paper is to survey literature on macroeconomic nonlinear dynamics.

2067

Abstract

Purpose

The purpose of this paper is to survey literature on macroeconomic nonlinear dynamics.

Design/methodology/approach

The paper identifies five influential types of models where the possible generation of endogenous cycles and chaotic motion arises. First, the frameworks that make use of the one‐hump logistic type equation; second, the models inspired on the growth literature of the 1940s; third, intertemporal utility maximization problems with increasing returns; fourth, models that can be represented as piecewise dynamic maps; and, fifth, bounded rationality – heterogeneous expectations setups.

Findings

The attention will be mainly focused on the theme of business cycles; an interpretation of the deterministic real business cycle model with increasing returns is proposed and a graphical analysis of the underlying system shows that strange attractors are observable for specific sets of parameter values.

Practical implications

The study of endogenous cycles in macroeconomic literature has important implications for policy: if fluctuations are due to deterministic reasons this may imply that by manipulating policy parameters governments may be able to change the qualitative nature of the economy's dynamics.

Originality/value

The paper gives a comprehensive view of nonlinear dynamics in macroeconomics. It shows that various relevant subjects might be addressed in this kind of models, e.g. economic growth, asset pricing, business cycles, consumption decisions, among others.

Details

Journal of Economic Studies, vol. 33 no. 6
Type: Research Article
ISSN: 0144-3585

Keywords

Article
Publication date: 1 April 1982

JOHN S. NICOLIS

Brain‐like structures have evolved by performing signal processing initially by minimizing “tracking errors” on a competitive basis. Such systems are highly complex and at the…

Abstract

Brain‐like structures have evolved by performing signal processing initially by minimizing “tracking errors” on a competitive basis. Such systems are highly complex and at the same time notoriously “disordered”. The functional trace of the cerebral cortex of the (human) brain is a good example. The Electroencephalogram (E.E.G) appears particularly fragmented during the execution of mental tasks, as well as during the recurrent episodes of R.E.M. sleep. A stochastically regular or a highly synchronized E.E.G on the other hand, characterises a drowsy (relaxing) or epileptic subject respectively and indicates—in both cases—a very incompetent information processor. We suggest that such behavioral changeovers are produced via bifurcations which trigger the thalamocortical non‐linear pacemaking oscillator to switch from an unstable limit cycle to a strange attractor regime (i.e. to chaos), or vice versa. Our analysis aims to show that the E.E.G's characteristics are not accidental but inevitable and even necessary and, therefore, functionally significant.

Details

Kybernetes, vol. 11 no. 4
Type: Research Article
ISSN: 0368-492X

Article
Publication date: 1 March 2001

Warren Smith

This article notes the growing attractiveness of concepts “borrowed” from chaos theory in organizational studies. Many of these interpretations display sentiments broadly…

Abstract

This article notes the growing attractiveness of concepts “borrowed” from chaos theory in organizational studies. Many of these interpretations display sentiments broadly congruent with a “postmodern” approach to organization. Indeed chaos theory itself is presented as part of a similar postmodern shift within natural science. However, these sentiments have been subject to stinging criticism by scientists. Here, the deterministic underpinning of chaos theory is used to show that chaos theory is an entirely modernist enterprise. In this case the indeterministic messages taken by organizational theorists are something of a misunderstanding. Consequently, I discuss whether this is enough to threaten the interdisciplinary status of chaos theory, particularly when it is used in a self-consciously ‘metaphorical’ fashion.

Details

International Journal of Organization Theory & Behavior, vol. 4 no. 3/4
Type: Research Article
ISSN: 1093-4537

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