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This paper argues that deep structures are embedded in engineering and technology discourse which work against an inclusive and locally relevant engineering ethics. The paper identifies the need for a new, process-oriented, approach to engineering ethics which enables a dynamic, reconfiguration of ethical issues. This approach must be based upon more locally relevant issues and formally recognise the primacy of the other in relation to the self. It proposes the concept of 'gestalt' as the basis for a theory of engineering ethics. In order to operational ise this theory the paper also submits the Johari Window as a useful device for engineering groups wishing to address local, ethical issues.

The modelling of time-varying systems is discussed and a description of parameter time variation containing 'fast' and 'slow' elements given. An adaptive identification and control algorithm is presented and stability and convergence results derived for a large class of time-varying systems.

The behaviour of n-input n-output systems with white noise is considered. An adaptive controller that simultaneously decouples the system and assigns its closed-loop poles is derived. This controller is of the 'hybrid' type and consists of a continuous-time control law, the parameters of which are updated using a discrete-time identification algorithm. Convergence and strong consistency results are derived for the identification algorithm and used to demonstrate that the adaptive control law does indeed produce a stable decoupled closed-loop system with correctly assigned poles.

The not previously considered problem of decoupling time varying multivariable systems is investigated and two dual-purpose algorithms, which decouple and regulate the system, are derived. One algorithm also gives pole assignment and the other minimum variance control. The algorithms are shown to stabilize and decouple the closed loop system.

In this work, strong consistency results for a class of stochastic gradient algorithms are developed where the system is not necessarily minimum-phase or stable and is assumed to be of the CARMA form. The analysis uses only standard martingale results, and strong consistency is shown to hold under certain persistent excitation conditions

The discretization of continuous time systems using shift operators often introduces non-minimum phase zeros. In this paper the conversion of continuous to delta operator systems and vice versa is considered and the relationship between the coefficients and poles of continuous time and delta operator systems is investigated for finite dimensional linear systems. The cases of both simple and multiple poles in the continuous time transfer functions are considered and it is shown that the poles, and coefficients of the delta operator transfer function converge to those of the associated continuous time system as the sampling time tends to zero.

An H∞ filter is presented for a class of multivariable systems. The Hm filtering problem is embedded in an L2 estimation problem which is then decoupled by diagonalisation of the polynomial matrix estimation criterion. The filter is obtained in closed form.

A key difficulty of the explicit approach to self-tuning control—both theoretically and computationally—is the need to solve a polynomial identity to generate the required controller coefficients. For systems with uncorrelated output noise, however, the identity has a simple solution, and in this paper the implications of this phenomenon are discussed in relation to self-tuning regulation. A suitable explicit algorithm is introduced, and it is shown that, under certain conditions, global stability and system identifiability can be established without recourse to sophisticated estimator management techniques.

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