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The aim of this paper is to explore the value preference space associated with the optimization and generalization performance of GEFeWSML.

In this paper, the authors modified the evaluation function utilized by GEFeWSML such that the weights assigned to each objective (i.e. error reduction and feature reduction) were varied. For each set of weights, GEFeWSML was used to evolve FMs for the face, periocular, and face + periocular templates. The best performing FMs on the training set (FMtss) and the best performing FMs on the validation set (FM*s) were then applied to the test set in order to evaluate how well they generalized to the unseen subjects.

By varying the weights assigned to each of the objectives, the authors were able to suggest values that would result in the best optimization and generalization performances for facial, periocular, and face + periocular recognition. GEFeWSML using these suggested values outperformed the previously reported GEFeWSML results, using significantly fewer features while achieving the same recognition accuracies statistically.

In this paper, the authors investigate the relative weighting of each objective using a value preference structure and suggest the best weights to be used for each biometric modality tested.

Cantilever plates subject to axial flow can lose stability by flutter and properties such as viscoelasticity and laminar friction affect dynamic stability. The purpose of the present study is to investigate the dynamic stability of viscoelastic cantilever plates subject to axial flow by using the differential quadrature method.

Equation of motion of the viscoelastic plate is derived by implementing Kelvin-Voigt model of viscoelasticity and applying inverse Laplace transformation. The differential quadrature method is employed to discretize the equation of motion and the boundary conditions leading to a generalized eigenvalue problem. The solution is verified using the existing results in the literature and numerical results are given for critical flow velocities

It is observed that higher aspect ratios lead to imaginary part of third frequency becoming negative and causing single-mode flutter instability. It was found that flutter instability does not occur at low aspect ratios. Moreover the friction coefficient is found to affect the magnitude of critical flow velocity, however, its effect on the stability behaviour is minor.

The effects of various problem parameters on the dynamic stability of a viscoelastic plate subject to axial flow were established. It was shown that laminar friction coefficient of the flowing fluid increases the critical fluid velocity and higher aspect ratios lead to single-mode flutter instability. The effect of increasing damping of viscoelastic material on the flutter instability was quantified and it was found that increasing viscoelasticity can lead to divergence instability.

This study aims to investigate the morphing concepts able to manipulate the dynamics of the downstream unsteadiness in the separated shear layers and, in the wake, be able to modify the upstream shock–boundary layer interaction (SBLI) around an A320 morphing prototype to control these instabilities, with emphasis to the attenuation or even suppression of the transonic buffet. The modification of the aerodynamic performances according to a large parametric study carried out at Reynolds number of 4.5 × 10⁶, Mach number of 0.78 and various angles of attack in the range of (0, 2.4)° according to two morphing concepts (travelling waves and trailing edge vibration) are discussed, and the final benefits in aerodynamic performance increase are evaluated.

This article examines through high fidelity (Hi-Fi) numerical simulation the effects of the trailing edge (TE) actuation and of travelling waves along a specific area of the suction side starting from practically the most downstream position of the shock wave motion according to the buffet and extending up to nearly the TE. The present paper studies through spectral analysis the coherent structures development in the near wake and the comparison of the aerodynamic forces to the non-actuated case. Thus, the physical mechanisms of the morphing leading to the increase of the lift-to-drag ratio and the drag and noise sources reduction are identified.

This study investigates the influence of shear-layer and near-wake vortices on the SBLI around an A320 aerofoil and attenuation of the related instabilities thanks to novel morphing: travelling waves generated along the suction side and trailing-edge vibration. A drag reduction of 14% and a lift-to-drag increase in the order of 8% are obtained. The morphing has shown a lift increase in the range of (1.8, 2.5)% for angle of attack of 1.8° and 2.4°, where a significant lift increase of 7.7% is obtained for the angle of incidence of 0° with a drag reduction of 3.66% yielding an aerodynamic efficiency of 11.8%.

This paper presents results of morphing A320 aerofoil, with a chord of 70cm and subjected to two actuation kinds, original in the state of the art at M = 0.78 and Re = 4.5 million. These Hi-Fi simulations are rather rare; a majority of existing ones concern smaller dimensions. This study showed for the first time a modified buffet mode, displaying periodic high-lift “plateaus” interspersed by shorter lift-decrease intervals. Through trailing-edge vibration, this pattern is modified towards a sinusoidal-like buffet, with a considerable amplitude decrease. Lock-in of buffet frequency to the actuation is obtained, leading to this amplitude reduction and a drastic aerodynamic performance increase.

AN ancient fable tells of strong brothers destined to great things. But one lay quietly, in his youth, applying goose grease to his muscles while the others disported among themselves in contest of strength. When the day of trial came it was the lone one, Atlas, who took the weight of the world upon his shoulders. The Greeks were neither fools nor strangers to work study.

Proposes to treat social law contracts by covering the two most important aspects of the contract of employment, and also the collective agreement. Covers the contract of employment in full with all the integral laws explained as required, including its characteristics, written particulars, sources or regulations, with regard to employers, are also covered. Lengthy coverage of the collective agreement is also included, showing legal as well as moral (!) requirements, also included are cases in law that are covered in depth.

In an article entitled “Collective Bargaining — a theoretical analysis” A. Flanders defined collective bargaining as an “…institution for the joint regulation of labour management and labour markets.” The collective agreement, the result of the collective bargain, is normally an uninforceable contract and is a very different legal notion from that of the contract of employment. The function of the collective agreement is to regulate relations between the collective parties, that is between the employer's association or an individual employer, and a union or unions. Such relations are known as relations of a collective nature. They could include procedure agreements between the collective parties in relation to no‐strikes or other industrial action before the disputes procedure has been exhausted; matters to do with the structure of negotiations between the parties; the constitution of the bodies set up for collective bargaining purposes; procedures on re‐ negotiation of the collective agreement; and so on. The collective agreement has however another function, the individual function, which regulates relations between employer and employee. Terms and conditions of employment are usually regulated by the collective agreement. Thus pay scales, hours of work, holidays, wages during illness, overtime work, any matters relating to training, re‐training, apprenticeship, are some from among the numerous subjects to be found in conditions of employment. Procedures which relate to the individual employee, such as grievance and disciplinary procedures, may equally feature as part of the terms and conditions of employment which emanate from the collective agreement. Indeed statute requires that the employer gives his employee particulars of this latter's major terms and conditions of employment.

THE American magazine Business Week recently dealt with the problem of work study in white collar areas and in the course of the article made the following comment: ‘The real impact of computer technology on work measurement and performance standards will come when it can take over more of the functions of the industrial engineer.’

THE following list of contracts placed by the Air Ministry during November is extracted from the December issue of The Ministry of Labour Gazette:—

THE following lists of contracts placed by the Air Ministry during September and October are extracted from the October and November issues of The Ministry of Labour Gazette:

SOCIAL scientists have not yet been able to formulate any general laws about behaviour in industry that are capable of broad application. In recent years, however, they have made many useful case studies of which the one just published by the Department of Scientific and Industrial Research is typical. It is an approach to the problem which can do much to increase the understanding of the way in which people react to common industrial situations.