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Abstract
We constructed a tool, called VooDooM, which converts datatypes in VDM-SL into SQL relational data models. The conversion involves transformation of algebraic types to maps and products, and pointer introduction. The conversion is specified as a theory of refinement by calculation. The implementation technology is strategic term rewriting in Haskell, as supported by the Strafunski bundle. Due to these choices of theory and technology, the road from theory to practise is straightforward.

Abstract
This paper addresses objectification, a formal specification technique which inspects the potential for object-orientation of a declarative model and brings the 'implicit objects' explicit. Criteria for such objectification are formalized and implemented in a runnable prototype tool which embeds VDM-SL into VDM++. The paper also includes a quick presentation of a (coinductive) calculus of such generated objects, framed as generalised Moore machines.

Abstract
Orchestrating software components, often from independent suppliers, became a central concern in software construction. Actually, as relevant as components themselves, are the ways in which they can be put together to interact and cooperate in order to achieve some common goal. Such is the role of the so-called software connectors: external coordination devices which ensure the flow of data and enforce synchronization constraints within a component's network. This paper introduces a new model for software connectors, based on relations extended in time, which aims to provide support for light inter-component dependency and effective external control.

Abstract
Delayed-feedback amplifiers are composed of, a forward gain amplifier, a feedback network and a time-delay element. Recently published results [1] claim the possibility of bandwidth enhancement for this type of systems, simply by a judicious choice of loop-gain, open loop poles and the net time-delay. This paper describes the design steps for a shunt-shunt feedback amplifier with an active delay on the feedback loop. The designed circuit was optimized for Free-Space Optical (FSO) line-of-sight receivers. Achieved results show that the inclusion of the active delay, improve bandwidth in a maximum of 60%. A maximum of 1.5THzO. GBW (11kO. transimpedance gain) was achieved with a photodiode having intrinsic capacitance of 100pF.