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A GENERAL solution is obtained for the diffusion of stress in n equal and equally spaced stringers in a stiffened panel subject to any boundary conditions at the ends of the stringers.

With the advent of the Montreal Protocol, the removal of flux residues from printed circuit assemblies using solvents based on CFC‐113 is no longer an acceptable option. An alternative range of cleaning technologies is being developed and marketed for this purpose, and the aim of this work was to study the efficiency of a variety of these alternative cleaning regimes after IR reflow soldering. The results indicated that: (i) all the cleaning regimes were capable of removing flux and flux residues after standard IR reflow soldering; (ii) as the level of flux contamination under the components increased, the ability of the cleaning regimes to clean the boards decreased; (iii) the cleaning regimes had varying problems in removing the flux residues after the non‐standard (overheat) IR profile processing; (iv) when additional flux is introduced under the components (i.e., non‐standard IR reflow), the delay between soldering and cleaning becomes important; and (v) the cleaning regimes exhibited a wide variation in their ability to clean under components with small stand‐off heights.

IT does not require a very large crystal ball to envisage the growth of aviation during the next fifteen years. Sea travel has become too slow; air travel has become reliable and more independent of weather conditions; world trade has forced travel into the remotest areas; industrial countries have become more affluent, and the urge for private world travel has accompanied affluence. It is not surprising, therefore, to hear the Chairman of the British Airport Authority, Peter Masefield, predict a fifteenfold growth in air traffic in the United Kingdom during the next twenty years and to find the F.A.A. confidently anticipating a doubling of passenger traffic in five years and a nine‐fold increase in small jets in the same period.

This study aims to demonstrate the numerical application of differential quadrature (DQ) methods and show the experimental application of free vibration analysis of fiber-metal laminated composite (FML) plates with various boundary conditions.

The FMLs are hybrid structures consisting of fiber-reinforced polymer matrix composites such as carbon, glass, aramid and different metal sheets, and are currently widely used in the automobile, aircraft and aerospace industries. Thus, free vibration analysis of these hybrid materials is necessary for the design process. The governing equations of motion are derived based on the classical plate theory. The DQ, generalized DQ (GDQ) and harmonic DQ (HDQ) differential quadrature methods have been used to solve the governing equations of an FML composite plate numerically. The accuracy and convergence of the numerical model have been verified by comparing the results available in the published literature with the results obtained from these methods. Moreover, an experimental procedure has been performed in order to compare the results against those of the numerical methods.

It is noteworthy that a high degree of similarity and accuracy was observed between the numerical results obtained by the DQ methods and the experimental results. Thus, the present study validates the applicability of the DQ methods for designing the FML composite plates.

In this study, the advantages of the DQ methods have been demonstrated differently from previous studies on the vibration analysis of the FML plates.

Cubic B‐spline differential quadrature methods have been introduced. As test problems, two different solutions of advection‐diffusion equation are chosen. The first test problem, the transportion of an initial concentration, and the second one, the distribution of an initial pulse, are simulated. The purpose of this paper is to simulate the test problems.

The cubic B‐spline functions are chosen as test functions in order to construct the differential quadrature method. The error between the numerical solutions and analytical solutions are measured using various error norms.

The cubic B‐spline differential quadrature methods have produced acceptable solution for advection‐diffusion equation.

The advection‐diffusion equation has never been solved by any differential quadrature method based on cubic B‐splines.

Purpose – This chapter focuses on individual differences in anxiety, by reviewing its neurobiology, cognitive effects, with an emphasis on decision-making, and recent developments in neuroeconomics.

Methodology – A review and discussion of anxiety and decision-making research.

Practical implications – This chapter argues that by making the step from emotional states to individual differences in emotion, neuroeconomics can extend its neurobiological roots and outreach its current clinical relevance.

Value of chapter – This chapter contributes to the literature on individual differences in emotion and their effects on decision-making, which is increasingly important in mainstream behavioral economics and neuroeconomics.

The approximate factorisation‐conjugate gradient squared (AF‐CGS) method has been successfully demonstrated for unsteady turbulent aerofoil flows and transonic inviscid flows in two and three dimensions. The method consists of a conjugate gradient solution of the linear system at each step with the ADI approximate factorisation as a preconditioner. In the present paper the method is adapted to obtain rapid convergence for steady aerofoil flows when compared to the basic explicit method. Modifications to the original method are described, convergence criteria are examined and the method is demonstrated for transonic flow including AGARD test case 9 for the RAE2822 aerofoil.

DURING some courses on production and management problems at the T.U.C. Training College job evaluation and merit rating were discussed. The notes used for that purpose form the basis of a booklet which the Trades Union Congress has published at 1s. 6d. Its purpose is to equip trade union representatives with an outline of the systems most widely used.

EUROCONTROL Mr J. P. W. Mallalicu, M.P., who succeeded Mr Roy Mason, M.P., as Minister of State, Board of Trade, has assumed the office of President of the Permanent Commission of Ministers of the European Organisation for the Safety of Air Navigation (EUROCONTROL) previously held by Mr Mason.

Aslib's annual report, which was considered at the Annual General Meeting in London on 7th June, made interesting reading and showed the association's steady progress. Membership is now 2,500, comprised chiefly of 922 industrial concerns, 221 Government departments and organisations, 295 public and national libraries and 301 universities and colleges. A point of interest is that there are only 403 individual members and this figure seems to be static having risen by only 5 in the last two years. Subscription income rose by £1,864 and Aslib's reserves are now £7,500. Some concern is expressed in the report about the finance of the Annual Conference, which showed a loss of £272. Many members are of the opinion that the conference fee is already too high, but the report suggests that rising costs may result in an even higher fee in the future.