Self Timed Control Of Concurrent Processes

'Et moi ... ~ si j'avait su comment en revenir. One service mathematics has rendered thl je n'y serais point aile: human race. It has put common sense back where it belongs. on the topmost shelf nexl Jules Verne to the dusty canister labelled 'discarded non· The series is divergent; therefore we may be sense'. Eric T. Bell able to do something with it O. Heaviside Mathematics is a tool for thought. A highly necessary tool in a world where both feedback and non· Iinearities abound. Similarly, all kinds of parts of mathematics serve as tools for other parts and fO! other sciences. Applying a simple rewriting rule to the quote on the right above one finds such statements as: 'One service topology has rendered mathematical physics .. .'; 'One service logic has rendered com· puter science ... '; 'One service category theory has rendered mathematics .. .'. All arguably true. And all statements obtainable this way form part of the raison d'etre of this series.

This book constitutes the thoroughly refereed post-conference proceedings of 19th International Workshop on Power and Timing Modeling, Optimization and Simulation, PATMOS 2009, featuring Integrated Circuit and System Design, held in Delft, The Netherlands during September 9-11, 2009. The 26 revised full papers and 10 revised poster papers presented were carefully reviewed and selected from numerous submissions. The papers are organized in topical sections on variability & statistical timing, circuit level techniques, power management, low power circuits & technology, system level techniques, power & timing optimization techniques, self-timed circuits, low power circuit analysis & optimization, and low power design studies.

As CMOS semiconductor technology strides towards billions of transistors on a single die new problems arise on the way. They are concerned with the - minishing fabrication process features, which a?ect for example the gate-to-wire delay ratio. They manifest themselves in greater variations of size and operating parameters of devices, which put the overall reliability of systems at risk. And, most of all, they have tremendous impact on design productivity, where the costs of utilizing the growing silicon ‘real estate’ rocket to billions of dollars that have to be spent on design, veri?cation, and testing. All such problems call for new - sign approaches and models for digital systems. Furthermore, new developments in non-CMOS technologies, such as single-electron transistors, rapid single-?- quantum devices, quantum dot cells, molecular devices, etc. , add extra demand for new research in system design methodologies. What kind of models and design methodologies will be required to build systems in all these new technologies? Answering this question, even for each particular type of new technology generation, is not easy, especially because sometimes it is not even clear what kind of elementary devices are feasible there. This problem is of an interdisciplinary nature. It requires an bridges between di?erent scienti?c communities. The bridges must be built very quickly, and be maximally ?exible to accommodate changes taking place in a logarithmic timescale.

There is algebraic structure in time, computation and biological systems. Algebraic engineering exploits this structure to achieve better understanding and design. In this book, pure and applied results in semigroups, language theory and algebra are applied to areas ranging from circuit design to software engineering to biological evolution.

This volume features the refereed proceedings of the 17th International Workshop on Power and Timing Modeling, Optimization and Simulation. Papers cover high level design, low power design techniques, low power analog circuits, statistical static timing analysis, power modeling and optimization, low power routing optimization, security and asynchronous design, low power applications, modeling and optimization, and more.

Asynchronous Circuit Design for VLSI Signal Processing is a collection of research papers on recent advances in the area of specification, design and analysis of asynchronous circuits and systems. This interest in designing digital computing systems without a global clock is prompted by the ever growing difficulty in adopting global synchronization as the only efficient means to system timing. Asynchronous circuits and systems have long held interest for circuit designers and researchers alike because of the inherent challenge involved in designing these circuits, as well as developing design techniques for them. The frontier research in this area can be traced back to Huffman's publications `The Synthesis of Sequential Switching Circuits' in 1954 followed by Unger's book, `Asynchronous Sequential Switching Circuits' in 1969 where a theoretical foundation for handling logic hazards was established. In the last few years a growing number of researchers have joined force in unveiling the mystery of designing correct asynchronous circuits, and better yet, have produced several alternatives in automatic synthesis and verification of such circuits. This collection of research papers represents a balanced view of current research efforts in the design, synthesis and verification of asynchronous systems.

WelcometotheproceedingsofPATMOS2004,thefourteenthinaseriesofint- national workshops. PATMOS 2004 was organized by the University of Patras with technical co-sponsorship from the IEEE Circuits and Systems Society. Over the years, the PATMOS meeting has evolved into an important - ropean event, where industry and academia meet to discuss power and timing aspects in modern integrated circuit and system design. PATMOS provides a forum for researchers to discuss and investigate the emerging challenges in - sign methodologies and tools required to develop the upcoming generations of integrated circuits and systems. We realized this vision this year by providing a technical program that contained state-of-the-art technical contributions, a keynote speech, three invited talks and two embedded tutorials. The technical program focused on timing, performance and power consumption, as well as architectural aspects, with particular emphasis on modelling, design, charac- rization, analysis and optimization in the nanometer era. This year a record 152 contributions were received to be considered for p- sible presentation at PATMOS. Despite the choice for an intense three-day m- ting, only 51 lecture papers and 34 poster papers could be accommodated in the single-track technical program. The Technical Program Committee, with the - sistance of additional expert reviewers, selected the 85 papers to be presented at PATMOS and organized them into 13 technical sessions. As was the case with the PATMOS workshops, the review process was anonymous, full papers were required, and several reviews were received per manuscript.