Concurrent Design of Embedded Control Software

Embedded software design for mechatronic systems is becoming an increasingly time-consuming and error-prone task. In order to cope with the heterogeneity and complexity, a systematic model-driven design approach is needed, where several parts of the system can be designed concurrently. There is however a trade-off between concurrency efficiency and integration efficiency. In this paper, we present a case study on the development of the embedded control software for a real-world mechatronic system in order to evaluate how we can integrate concurrent and largely independent designed embedded system software parts in an efficient way. The case study was executed using our embedded control system design methodology which employs a concurrent systematic model-based design approach that ensures a concurrent design process, while it still allows a fast integration phase by using automatic code synthesis. The result was a predictable concurrently designed embedded software realization with a short integration time

Subband coding of digital audio signals without loss of quality

A subband coding system for high quality digital audio signals is described. To achieve low bit rates at a high quality level, it exploits the simultaneous masking effect of the human ear. It is shown how this effect can be used in an adaptive bit-allocation scheme. The proposed approach has been applied in two coding systems, a complex system in which signal is split into 26 subbands, each approximately one third of an octave wide, and a simpler 20-band system. Both systems have been designed for coding stereophonic 16-bit compact disk signals with a sampling frequency of 44.1 kHz. With the 26-band system high-quality results can be obtained at bit rates of 220 kb/s. With the 20-band system, similar results can be obtained at bit rates of 360 kb/

Aux frontières du maniérisme et du baroque

Traiter avec précision, en peu d’instants, le sujet que j’ai eu l’imprudence d’annoncer, tenter d’éclairer la zone intermédiaire entre deux styles que l’histoire a vu se succéder et qui sont apparentés l’un à l’autre, est une entreprise sans espoir. Si je m’arrête d’abord, avec quelque complaisance, au maniérisme, c’est qu’il gagne aujourd’hui sur le baroque dans l’esprit de la critique et qu’il est en train de le refouler au xviie siècle. Cela ne signifie pas, d’ailleurs, qu’il y aurait une ..