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Article
Publication date: 5 May 2015

Babruvahan Pandurang Ronge and Prashant Maruti Pawar

– This paper aims to focus on the stochastic analysis of composite rotor blades with matrix cracking in forward flight condition.

Abstract

Purpose

This paper aims to focus on the stochastic analysis of composite rotor blades with matrix cracking in forward flight condition.

Design/methodology/approach

The effect of matrix cracking and uncertainties are introduced to the aeroelastic analysis through the cross-sectional stiffness properties obtained using thin-walled beam formulation, which is based on a mixed force and a displacement method. Forward flight analysis is carried out using an aeroelastic analysis methodology developed for composite rotor blades based on the finite element method in space and time. The effects of matrix cracking are introduced through the changes in the extension, extension-bending and bending matrices of composites, whereas the effect of uncertainties are introduced through the stochastic properties obtained from previous experimental and analytical studies.

Findings

The stochastic behavior of helicopter hub loads, blade root forces and blade tip responses are obtained for different crack densities. Further, assuming the behavior of progressive damage in same beam is measurable as compared to its undamaged state, the stochastic behaviors of delta values of various measurements are studied. From the stochastic analysis of forward flight behavior of composite rotor blades at various matrix cracking levels, it is observed that the histograms of these behaviors get mixed due to uncertainties. This analysis brings out the parameters which can be used for effective prediction of matrix cracking level under various uncertainties.

Practical implications

The behavior is useful for the development of a realistic online matrix crack prediction system.

Originality/value

Instead of introducing the white noise in the simulated data for testing the robustness of damage prediction algorithm, a systematic approach is developed to model uncertainties along with damage in forward flight simulation.

Details

Aircraft Engineering and Aerospace Technology: An International Journal, vol. 87 no. 3
Type: Research Article
ISSN: 0002-2667

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Article
Publication date: 6 August 2010

Chetan S. Jarali and D. Roy Mahapatra

The purpose of this paper is to investigate the stress distribution in shape memory alloy (SMA) composite due to phase transformations in the fiber in view of the applied…

Abstract

Purpose

The purpose of this paper is to investigate the stress distribution in shape memory alloy (SMA) composite due to phase transformations in the fiber in view of the applied boundary conditions on the matrix.

Design/methodology/approach

A consistent homogenization of a SMA wire‐reinforced polymer composite volume element undergoing quasi‐static deformation was performed and SMA wire‐matrix interface behaviour was presented. For the SMA wire, a one‐dimensional phenomenological constitutive model was used. Eshelby's inclusion theory was employed for homogenization. A strain averaging approach was reviewed in which the average strain was substituted back to obtain the expressions for the effective stiffness, the inelastic strain, and the average stresses in the constituent phases. In order to study the stress distribution in SMA composite and constituent phases (fiber and matrix) as a consequence of the SMA wire‐matrix interface effect, interfacial stress model was derived. Interfacial axial and shear stress distribution is characterized for forward and reverse phase transformations. Finally, the thermomechanical behaviours were computed by applying strain energy approach incorporating the interface effects.

Findings

The results presented show that due to the difference between the shear modulus of matrix and SMA wire, and because of the strain non‐uniformity at the SMA wire‐matrix interface, shear stress is developed within the matrix under the axial loading of the representative volume element (RVE). The shear stress increases more rapidly as the SMA wire radius is increased but not with increase in the length. However, the axial stress does not increase much with increase in the SMA wire radius and length. Further, the average stress equation of the RVE at the SMA wire‐matrix interface is effectively addressed. The modeling approach is successfully validated extensively for different geometric and volumetric parameters for different loading conditions. It is evident that the interface effect of SMA wire composites is SMA stiffness dominated due to the fact that the geometric parameters do not influence much the stresses as compared to the change in SMA wire stiffness.

Originality/value

The approach is based on modeling the fiber matrix interface effect using homogenization scheme. Further, the strain energy approach is applied to compute the stress‐strain response. This indicates the importance of modeling the SMA wire‐matrix interface effect, and in particular, the energy exchange between the constituent phases. The results have been compared for different geometric parameters as well as volume fractions of the constituent phases under different loading conditions.

Details

Multidiscipline Modeling in Materials and Structures, vol. 6 no. 2
Type: Research Article
ISSN: 1573-6105

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Article
Publication date: 1 June 2000

R.V.N. Melnik

The dynamics of coupling between spectrum and resolvent under ε‐perturbations of operator and matrix spectra are studied both theoretically and numerically. The phenomenon…

Abstract

The dynamics of coupling between spectrum and resolvent under ε‐perturbations of operator and matrix spectra are studied both theoretically and numerically. The phenomenon of non‐trivial pseudospectra encountered in these dynamics is treated by relating information in the complex plane to the behaviour of operators and matrices. On a number of numerical results we show how an intrinsic blend of theory with symbolic and numerical computations can be used effectively for the analysis of spectral problems arising from engineering applications.

Details

Engineering Computations, vol. 17 no. 4
Type: Research Article
ISSN: 0264-4401

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Article
Publication date: 27 January 2020

Ankang Liu, Bing Wang and Fei Li

This paper aims to study the effect of elevated temperature on the compression behaviour of carbon fibre polyphenylene sulphide (CF/PPS) laminates notched and unnotched…

Abstract

Purpose

This paper aims to study the effect of elevated temperature on the compression behaviour of carbon fibre polyphenylene sulphide (CF/PPS) laminates notched and unnotched specimens made by film stacking method (FSM).

Design/methodology/approach

The surface of CF was coated with a silane coupling agent to form an effective transition layer with PPS, so as to enhance the interfacial interaction between CF and PPS. Considering the influence of fabrication pressure, forming temperature and cooling rate on the properties of laminates to obtain a reasonable preparation process. Conducting a compressive experiment of notched and unnotched specimens at different temperatures, which failure modes were examined by scanning electron microscope and stereo microscope.

Findings

The experimental observations highlight that with the increase of temperature, the transition failure mode from fibre broken to kink-band appeared in unnotched specimens, which were closely attributed to the matrix state. The notched specimens appeared more complex failure mode, which can be attributed to the joint effect of temperature and opening hole.

Research implications

A simple way of FSM for composite material laminates has been developed by using woven CF and PPS films.

Originality/value

The outcome of this study will help to understand the compression response mechanism of composite materials made by FSM at different temperature.

Details

Pigment & Resin Technology, vol. ahead-of-print no. ahead-of-print
Type: Research Article
ISSN: 0369-9420

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Article
Publication date: 1 February 2000

Antony Beckett, Paul Hewer and Barry Howcroft

Deregulation and the emergence of new forms of technology have created highly competitive market conditions which have had a critical impact upon consumer behaviour. Bank…

Abstract

Deregulation and the emergence of new forms of technology have created highly competitive market conditions which have had a critical impact upon consumer behaviour. Bank providers must, therefore, attempt to better understand their customers in an attempt not only to anticipate but also to influence and determine consumer buying behaviour. The paper accordingly presents and develops a model which attempts to articulate and classify consumer behaviour in the purchasing of financial products and services. The theoretical insights generated by this model are then used to examine qualitative research data gained from focus group discussions on consumers’ attitudes to their financial providers and their financial products. Finally, these findings are examined for the potential insights they provide to bank providers attempting to identify appropriate strategies which are conducive to increased customer retention and profitability.

Details

International Journal of Bank Marketing, vol. 18 no. 1
Type: Research Article
ISSN: 0265-2323

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Article
Publication date: 1 April 1978

HÅKAN ANDERSSON

The theory of relatively closed systems first appeared in Kybernetes as two consecutive papers by Grubbström This work was a development of studies in cybernetic modelling…

Abstract

The theory of relatively closed systems first appeared in Kybernetes as two consecutive papers by Grubbström This work was a development of studies in cybernetic modelling performed by Lange and Klir and Valach. This paper deals with an application taken from the field of inventory control. The purpose is to show how the theory of relatively closed systems can be used to formulate models, analyse stability conditions and compute equilibrium values for the variables involved.

Details

Kybernetes, vol. 7 no. 4
Type: Research Article
ISSN: 0368-492X

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Article
Publication date: 8 May 2017

Yong Liu and Kevin W. Li

The purpose of this paper is to propose a novel prospect-based two-sided matching decision model for matching supply and demand of technological knowledge assisted by a…

Abstract

Purpose

The purpose of this paper is to propose a novel prospect-based two-sided matching decision model for matching supply and demand of technological knowledge assisted by a broker. This model enables the analyst to account for the stakeholders’ psychological behaviours and their impact on the matching decision in an open innovation setting.

Design/methodology/approach

The prospect theory and grey relational analysis are used to develop the proposed two-sided matching decision framework.

Findings

By properly calibrating model parameters, the case study demonstrates that the proposed approach can be applied to real-world technological knowledge trading in a market for technology (MFT) and yields matching results that are more consistent with the reality.

Research limitations/implications

The proposed model does not differentiate the types of knowledge exchanged (established vs novel, tacit vs codified, general vs specialized) (Ardito et al., 2016, Nielsen and Nielsen, 2009). Moreover, the model focuses on incorporating psychological behaviour of the MFT participants and does not consider their other characteristics.

Practical implications

The proposed model can be applied to achieve a better matching between technological knowledge suppliers and users in a broker-assisted MFT.

Social implications

A better matching between technological knowledge suppliers and users can enhance the success of open innovation, thereby contributing to the betterment of the society.

Originality/value

This paper furnishes a novel theoretical model for matching supply and demand in a broker-assisted MFT. Methodologically, the proposed model can effectively capture market participants’ psychological considerations.

Details

Journal of Knowledge Management, vol. 21 no. 3
Type: Research Article
ISSN: 1367-3270

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Article
Publication date: 1 June 1993

Carol A. O′Connor

Seeks to help managers to recognize different types of resistanceand how to react to them. Categorizes types of resistance (resistancequadrants) and presents questions to…

Abstract

Seeks to help managers to recognize different types of resistance and how to react to them. Categorizes types of resistance (resistance quadrants) and presents questions to help identify the personality of the resistor. Resistance to change can be intentional or unintentional, covert or overt. Describes causes of resistance and presents diagnostic questions. Managers with self‐awareness and a sense of humour are most successful in overcoming resistance to change.

Details

Leadership & Organization Development Journal, vol. 14 no. 6
Type: Research Article
ISSN: 0143-7739

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Article
Publication date: 1 October 2003

Karthik Namasivayam

This paper responds to the call for increased attention to the consumer's point of view in modeling the service exchange. A novel conceptualization of a service product is…

Abstract

This paper responds to the call for increased attention to the consumer's point of view in modeling the service exchange. A novel conceptualization of a service product is presented. Further, extending extant research that conceptualizes consumers as “partial employees”, this paper treats consumers as “transient” employees. Next, drawing on the literatures in human resources, specifically Karasek's job demand‐control model, a theoretical model of consumer satisfaction is developed and presented. Attention is also drawn to a typology of services based on the level of consumer participation. Managerial recommendations are developed and presented on the basis of these arguments.

Details

International Journal of Service Industry Management, vol. 14 no. 4
Type: Research Article
ISSN: 0956-4233

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Article
Publication date: 16 October 2009

N. Sivakumar

The purpose of this paper is to develop a typology of organization behavior based on the guidelines from Manusmriti, an ancient Indian law text. The paper also purports to

Abstract

Purpose

The purpose of this paper is to develop a typology of organization behavior based on the guidelines from Manusmriti, an ancient Indian law text. The paper also purports to provide guidelines from the text for values‐based corporate governance.

Design/methodology/approach

The paper first develops an organizational behavior typology based on Manusmriti. The paper then provides guidelines for various aspects of values‐based corporate governance.

Findings

The paper finds that the guidelines from Manusmriti are relevant in providing a holistic approach to corporate governance which promotes ethical and social idealism.

Practical implications

The paper has practical implications to practitioners of corporate governance in terms of developing structures which promote ethical and socially responsible behavior.

Originality/value

The originality of the paper is in deriving guidelines for values‐based corporate governance from Manusmriti.

Details

Corporate Governance: The international journal of business in society, vol. 9 no. 5
Type: Research Article
ISSN: 1472-0701

Keywords

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