Adaptive hardware/evolvable hardware - The state of the art and the prospectus for future development

With great pleasure, we would like to welcome you to this special issue of the International Journal of Knowledge-based and Intelligent Engineering Systems. The motivation of its selected topic – Adaptive Hardware/Evolvable Hardware – the State of the Art and the Prospectus for Future Development – is deeply justified. Nevertheless, it is hardware implementation of the most benefit for the society and indeed most revolutionizing application of Evolutionary Computation (EC) by leading to the so-called Evolvable Hardware (EHW). These new EC based methodologies make possible the hardware implementation of both genetic encoding and artificial evolution, having a new brand of machines as a result. This type of machine is evolved to attain a desired behaviour that means they have a behavioural computational intelligence. There is no more difference between adaptation and design concerning these machines, these two concepts representing no longer opposite concepts. A dream of technology far years ago currently became reality: adaptation transfer from software to hardware is possible by the end. Much more, the electronics engineering as a profession was radically changed: the most based on soldering assembling manufacturing technologies are largely replaced now by programming circuitry-based technologies, including EHW technologies. This new design methodology for the electronic circuits and systems is not a fashion. It is suitable to the special uncertain, imprecise or incomplete defined realworld problems, claiming a continuous adaptation and evolution too. An increased efficiency of the methodology may be obtained by its application in the soft computing framework that means in aggregation with other intelligent technologies such as fuzzy logic (FS) and neural networks (NN), Artificial Immune Systems (AIS), evolutionary algorithms (EA). Dramatic changes happen in the relation between hardware and the application environment, and this in case of malicious faults or need for emergent new functions that claim for in-situ synthesis of a totally new hardware configuration. EHW is suitable for flexibility and survivability of autonomous systems. EHW survivability means to maintain functionality coping with changes in hardware characteristics under the circumstances of adverse environmental conditions as for example: temperature variations, radiation impacts, aging and malfunctions. EHW flexibility means the availability to create new functionality required by changes in requirements or environment.