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Inspired by a recent review article on the Automation of the Mining, Mineral, and Metal Processing Industry (MMM), this paper will discuss some important ”patches” of computer aided measurement processes in the MMM processing industries. Both evaluation of measurement data, as well as real-time control of the measurement processes will be covered. Notes will be given on the use of machine vision, electrochemical potential, optical emission spectrometry, and X-ray spectrometry. Some visions for the future will be offered.

The term ‘validation’ is used ubiquitously in association with the modelling activities of numerous disciplines including social, political, natural, physical sciences, and engineering. There is however, a wide range of definitions which give rise to very different interpretations of what activities the process involves. Analyses of results from the present large international effort in modelling radioactive waste disposal systems illustrate the urgent need to develop a common approach to model validation. Some possible explanations are offered to account for the present state of affairs. We believe that a rigorous approach to validation must necessarily be based on a thorough understanding and application of the theory of simulation and modelling. The methodology developed treats model validation and code verification in a systemic and systematic fashion. In fact, this approach may be regarded as a comprehensive framework to assess the adequacy of any simulation study.

An idea for a time-coding analog-to-digital converter using an exponential voltage sweep is presented. The technique inherently offers the possibility of convenient automatic recalibration in order to compensate for long-term drift. Thus, the converter is particularly well suited for on-line use in automatic digital data reduction systems. Attention is paid to the calibration and use of the converter. A design procedure is suggested and the obtainable accuracy evaluated in terms of the design parameters. Some comments are made concerning the merits of the scheme as compared with the most common existing systems.

This paper relates to an exploratory computer control project for the digital control of a cement plant. The control of the clinker cooler was part of the project. State variable techniques were applied for the synthesis of the control system. Here, the emphasis will be on off-line simulation. A control law will be generated for the control of the over grate differential pressure. It is claimed that simulation techniques are essential tools for the successful design and implementation of digital control in industry.

PPCP, A Process and Production Control Program, is a “fill-in-the-form” programming system for control applications. The system includes a number of standard modules for all normal functions performed in control environments. Some of the modules are outlined. In addition, PPCP allows effective inclusion of user's programs. Such an example, is the main topic of the paper. It is shown, how a user-written multivariable control program, related to a clinker cooler, can be integrated into PPCP. Finally, proper operation of the control loop, is confirmed through real-time simulation. The advantages of using PPCP over normal high-level, e.g. FORTRAN, programming techniques, becomes obvious. In particular, a saving in programming, at least 10-fold, is claimed. Also, it is claimed, that real time simulation can be very valuable as a debugging tool.