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This is the second of two papers reporting work carried out under a programme sponsored by the Department of Trade and Industry (DTI), involving collaboration between the above companies and research centres. The objectives of the programme are to identify/develop lead‐free alternatives to Sn‐40Pb solder, progress towards the development of which is described in this paper. A number of promising alloys have been selected for trial in a further round of experimentation.

The paper presents the results of extensive studies on circuit board solderability comparing wetting balance and IPC test methods through performance in vapour phase and wave soldering operations. The effects on solderability of key parameters are examined and compared with storage times of one year, and accelerated ageing using damp heat, dry heat and steam oxygen. An evaluation is made of tin‐lead alloys from 40/60 to 70/30 in solder coating thicknesses from 0·1 to 1·0 mil.

Richard Williams has been appointed to the Board of Micaply International as Marketing Director. He has extensive experience of the European printed circuit industry with periods spent in the UK, Sweden and Germany.

The three European Community manufacturers of commercially available wetting balances for measuring the solderability of electronic components have participated in an intercomparison assessment of surfaces of standard solderability that have the potential for calibrating the balance instruments. The development of the standard surfaces, as well as the small adjustments needed to improve the uniformity of design of the different instruments, and the standardisation of the procedures for their use, have been described in the preceding papers in this series. This paper gives details of the experimental procedures used for the intercomparison and the significance of the comparative data from each balance type.

Sweden, with a 3.4 million labour force, 45 per cent of it in commerce, transport and the service industries, tackles the problem of re‐training in a thoroughly imaginative way, as a film Investment in Manpower (col, 30 min) shows. Their National Labour Board deals with it in the round, fitting the men to the jobs, and treating its material throughout as human beings with modern human needs. There are no age limits, and prejudices about being too old to learn are firmly squashed. Rail fares to attend interview are paid, moving costs met, and grants given to keep the home going while training.

The subject of the quantitative measurement of solderability of electronic components is introduced. The wetting balance in various configurations and modes of operation is being used as the focal point to establish a quantitative measurement capability for solderability of conventional leaded components, surface mounting components and printed circuit interconnections. The principles of operation of the wetting balance and the factors that influence the measurement are discussed. This paper is the first of a series that will cover the development of traceable reference standards for wetting balance calibration, the influence of instrumental design on the measurement, the standardisation of the measurement procedures, the choice and evaluation of a solderability index for the dynamic measurement, and the traceability of the measurement to international standards.

In this chapter we discuss model selection and predictive accuracy tests in the context of parameter and model uncertainty under recursive and rolling estimation schemes. We begin by summarizing some recent theoretical findings, with particular emphasis on the construction of valid bootstrap procedures for calculating the impact of parameter estimation error. We then discuss the Corradi and Swanson (2002) (CS) test of (non)linear out-of-sample Granger causality. Thereafter, we carry out a series of Monte Carlo experiments examining the properties of the CS and a variety of other related predictive accuracy and model selection type tests. Finally, we present the results of an empirical investigation of the marginal predictive content of money for income, in the spirit of Stock and Watson (1989), Swanson (1998) and Amato and Swanson (2001).

The development and characterisation of a prototype solderability reference standard based on a gold‐plated nickel sample has been described previously. This material has now been tested in an intercomparison with several European laboratories. The results presented here show that a high degree of repeatability is achievable. These results substantiate earlier ones and confirm this material's applicability as a solderability reference material.

The purpose of this paper is to present an immersed volume method that accounts for solid conductive bodies (hat‐shaped disk) in calculation of time‐dependent, three‐dimensional, conjugate heat transfer and fluid flow.

The incompressible Navier‐Stokes equations and the heat transfer equations are discretized using a stabilized finite element method. The interface of the immersed disk is defined and rendered by the zero isovalues of a level set function. This signed distance function allows turning different thermal properties of each component into homogeneous parameters and it is coupled to a direct anisotropic mesh adaptation process enhancing the interface representation. A monolithic approach is used to solve a single set of equations for both fluid and solid with different thermal properties.

In the proposed immersion technique, only a single grid for both air and solid is considered, thus, only one equation with different thermal properties is solved. The sharp discontinuity of the material properties was captured by an anisotropic refined solid‐fluid interface. The robustness of the method to compute the flow and heat transfer with large materials properties differences is demonstrated using stabilized finite element formulations. Results are assessed by comparing the predictions with the experimental data.

The proposed method demonstrates the capability of the model to simulate an unsteady three‐dimensional heat transfer flow of natural convection, conduction and radiation in a cubic enclosure with the presence of a conduction body. A previous knowledge of the heat transfer coefficients between the disk and the fluid is no longer required. The heat exchange at the interface is solved and dealt with naturally.

This study investigates the impact of the enhanced continuous disclosure regime introduced in December 2002 on several measures of information risk in NZX‐listed stocks. We employ two microstructure models and an intraday data set to measure information risk in a sample of 71 stocks. Our empirical results show that the reforms enacted in December 2002 had no significant effect on either the level of information‐based trading or the adverse selection component of market spreads in our sample of NZX‐listed stocks.