Power consumption of VLSI (Very Large Scale Integrated) circuits has been growing at an alarmingly rapid rate. This increase in power consumption, coupled with the increasing demand for portable/hand-held electronics, has made power consumption a dominant concern in the design of VLSI circuits today. Traditionally, dynamic (switching) power has dominated the total power consumption of an IC. However, due to current scaling trends, leakage power has now become a major component of the total power consumption in VLSI circuits. Leakage power reduction is especially important in portable/hand-held electronics such as cell-phones and PDAs. This book presents two techniques aimed at reducing leakage power in digital VLSI ICs. The first technique reduces leakage through the selective use of high threshold voltage sleep transistors. The second technique reduces leakage by applying the optimal Reverse Body Bias (RBB) voltage. This book also shows readers how to turn the leakage problem into an opportunity, through the use of sub-threshold logic.

Power consumption of VLSI (Very Large Scale Integrated) circuits has been growing at an alarmingly rapid rate. This increase in power consumption, coupled with the increasing demand for portable/hand-held electronics, has made power consumption a dominant concern in the design of VLSI circuits today. Traditionally dynamic (switching) power has dominated the total power consumption of VLSI circuits. However, due to process scaling trends, leakage power has now become a major component of the total power consumption in VLSI circuits. This dissertation explores techniques to reduce leakage, as well as techniques to exploit leakage currents through the use of sub-threshold circuits. This dissertation consists of two studies. In the first study, techniques to reduce leakage are presented. These include a low leakage ASIC design methodology that uses high VT sleep transistors selectively, a methodology that combines input vector control and circuit modification, and a scheme to find the optimum reverse body bias voltage to minimize leakage. As the minimum feature size of VLSI fabrication processes continues to shrink with each successive process generation (along with the value of supply voltage and therefore the threshold voltage of the devices), leakage currents increase exponentially. Leakage currents are hence seen as a necessary evil in traditional VLSI design methodologies. We present an approach to turn this problem into an opportunity. In the second study in this dissertation, we attempt to exploit leakage currents to perform computation. We use sub-threshold digital circuits and come up with ways to get around some of the pitfalls associated with sub-threshold circuit design. These include a technique that uses body biasing adaptively to compensate for Process, Voltage and Temperature (PVT) variations, a design approach that uses asynchronous micro-pipelined Network of Programmable Logic Arrays (NPLAs) to help improve the throughput of sub-threshold designs, and a method to find the optimum supply voltage that minimizes energy consumption in a circuit.

IT changes everyday’s life, especially in education and medicine. The goal of ITME 2014 is to further explore the theoretical and practical issues of Ubiquitous Computing Application and Wireless Sensor Network. It also aims to foster new ideas and collaboration between researchers and practitioners. The organizing committee is soliciting unpublished papers for the main conference and its special tracks.

Transactions on HiPEAC aims at the timely dissemination of research contributions in computer architecture and compilation methods for high-performance embedded computer systems. Recognizing the convergence of embedded and general-purpose computer systems, this journal publishes original research on systems targeted at specific computing tasks as well as systems with broad application bases. The scope of the journal therefore covers all aspects of computer architecture, code generation and compiler optimization methods of interest to researchers and practitioners designing future embedded systems. This third issue contains 14 papers carefully reviewed and selected out of numerous submissions and is divided into four sections. The first section contains the top four papers from the Third International Conference on High-Performance Embedded Architectures and Compilers, HiPEAC 2008, held in Göteborg, Sweden, in January 2008. The second section consists of four papers from the 8th MEDEA Workshop held in conjunction with PACT 2007 in Brasov, Romania, in September 2007. The third section contains two regular papers and the fourth section provides a snapshot from the First Workshop on Programmability Issues for Multicore Computers, MULTIPROG, held in conjunction with HiPEAC 2008.

Very Large Scale Integration (VLSI) Systems refer to the latest development in computer microchips which are created by integrating hundreds of thousands of transistors into one chip. Emerging research in this area has the potential to uncover further applications for VSLI technologies in addition to system advancements. Design and Modeling of Low Power VLSI Systems analyzes various traditional and modern low power techniques for integrated circuit design in addition to the limiting factors of existing techniques and methods for optimization. Through a research-based discussion of the technicalities involved in the VLSI hardware development process cycle, this book is a useful resource for researchers, engineers, and graduate-level students in computer science and engineering.

The US, Europe, Japan and China are racing to develop the next generation of supercomputers – exascale machines capable of 10 to the 18th power calculations a second – by 2020. But the barriers are daunting: the challenge is to change the paradigm of high-performance computing. The 2012 biennial high performance workshop, held in Cetraro, Italy in June 2012, focused on the challenges facing the computing research community to reach exascale performance in the next decade. This book presents papers from this workshop, arranged into four major topics: energy, scalability, new architectural concepts and programming of heterogeneous computing systems. Chapter 1 introduces the status of present supercomputers, which are still about two orders of magnitude separated from the exascale mark. Chapter 2 examines energy demands, a major limiting factor of today's fastest supercomputers; the quantum leap in performance required for exascale computing will require a shift in architectures and technology. In Chapter 3, scalable computer paradigms for dense linear algebra on massive heterogeneous systems are presented, and Chapter 4 discusses architectural concepts. Finally, Chapter 5 addresses the programming of heterogeneous systems. This book will be of interest to all those wishing to understand how the development of modern supercomputers is set to advance in the next decade.

This book constitutes the refereed proceedings of the 11th Asia-Pacific Computer Systems Architecture Conference, ACSAC 2006. The book presents 60 revised full papers together with 3 invited lectures, addressing such issues as processor and network design, reconfigurable computing and operating systems, and low-level design issues in both hardware and systems. Coverage includes large and significant computer-based infrastructure projects, the challenges of stricter budgets in power dissipation, and more.