Reducing power/energy consumption is an important goal for all computersystems, from servers to battery-driven hand-held devices. To achieve this goal, the energy consumption of all system components needs to be redu...
详细信息
Reducing power/energy consumption is an important goal for all computersystems, from servers to battery-driven hand-held devices. To achieve this goal, the energy consumption of all system components needs to be reduced. One of the most power-hungry components is the off-chip DRAM, even when it is idle. DRAMs support different power-saving modes, such as self-refresh and power-down, but employing them every time the DRAM is idle, reduces performance due to their power-up latencies. The self-refresh mode offers large power savings, but incurs a long power-up latency. The power-down mode, on the other hand, has a shorter power-up latency, but provides lower power savings. In this paper, we propose and evaluate a novel power-saving policy that combines the best of both power-saving modes in order to achieve significant power reductions with a marginal performance penalty. To accomplish this, we use a history-based predictor to forecast the duration of an idle period and then either employ self-refresh, or power-down, or a combination of both power saving modes. Significant refinements are made to the predictor to maximize the energy savings and minimize the performance penalty. The presented policy is evaluated using several applications from the multimedia domain and the experimental results show that it reduces the total DRAM energy consumption between 68.8% and 79.9% at a negligible performance penalty between 0.3% and 2.2%.
This paper presents a novel method for classification of multi-lead electrocardiogram (ECG) signals. The feature extraction is based on the random projection (RP) concept for dimensionality reduction. Furthermore, the...
详细信息
This paper presents a novel method for classification of multi-lead electrocardiogram (ECG) signals. The feature extraction is based on the random projection (RP) concept for dimensionality reduction. Furthermore, the classification is performed by a neuro-fuzzy classifier. Such a model can be easily implemented on portable systems for practical applications in both health monitoring and diagnostic purposes. Moreover, the RP implementation on portable systems is very challenging featuring both energy efficiency and feasibility. The proposed method is tested on a 12-lead ECG database consisting of 20 beats during normal sinus rhythm, 20 beats with myocardial infarction and 20 beats showing cardiomyopathy for 60 different subjects. The experiments give a recognition rate of 100% for a small number of RP coefficients (only 25), i.e. after a considerable dimensionality reduction of the input ECG signal. The results are very promising, not only from the classification performance point of view, but also while targeting a low-complexity feature extraction in terms of computation requirements and memory usage for real-time operation on a wireless wearable sensor platform.
Three-dimensional (3D) circuits reduce communication delay in multicore SoCs, and enable efficient integration of cores, memories, sensors, and RF devices. However, vertical integration of layers exacerbates the relia...
详细信息
Three-dimensional (3D) circuits reduce communication delay in multicore SoCs, and enable efficient integration of cores, memories, sensors, and RF devices. However, vertical integration of layers exacerbates the reliability and thermal problems, and cooling efficiency becomes a limiting factor. Liquid cooling is a solution to overcome the accelerated thermal problems imposed by multi-layer architectures. In this paper, we first provide a 3D thermal simulation model including liquid cooling, supporting both fixed and variable fluid injection rates. Our model has been integrated in HotSpot to study the impact on multicore SoCs. We design and evaluate several dynamic management policies that complement liquid cooling. Our results for 3D multicore SoCs, which are based on 3D versions of UltraSPARC T1, show that thermal management approaches that combine liquid cooling with proactive task allocation are extremely effective in preventing temperature problems. Our proactive management technique provides an additional 75% average reduction in hot spots in comparison to applying only liquid cooling. Furthermore, for systems capable of varying the coolant flow rate at runtime, our feedback controller increases the improvement to 95% on average.
Technology scaling has caused the feature sizes to shrink continuously, whereas interconnects, unlike transistors, have not followed the same trend. Designing 3D stack architectures is a recently proposed approach to ...
详细信息
ISBN:
(纸本)9783981080155
Technology scaling has caused the feature sizes to shrink continuously, whereas interconnects, unlike transistors, have not followed the same trend. Designing 3D stack architectures is a recently proposed approach to overcome the power consumption and delay problems associated with the interconnects by reducing the length of the wires going across the chip. However, 3D integration introduces serious thermal challenges due to the high power density resulting from placing computational units on top of each other. In this work, we first investigate how the existing thermal management, power management and job scheduling policies affect the thermal behavior in 3D chips. We then propose a dynamic thermally-aware job scheduling technique for 3D systems to reduce the thermal problems at very low performance cost. Our approach can also be integrated with power management policies to reduce energy consumption while avoiding the thermal hot spots and large temperature variations.
Track reconstruction is a vital aspect of High-Energy Physics (HEP) and plays a critical role in major experiments. In this study, we delve into unexplored avenues for particle track reconstruction and hit clustering....
详细信息
作者：
Dutt, NikilRegazzoni, Carlo S.Rinner, BernhardYao, XinNikil Dutt (Fellow
IEEE) received the Ph.D. degree from the University of Illinois at Urbana–Champaign Champaign IL USA in 1989.""He is currently a Distinguished Professor of computer science (CS) cognitive sciences and electrical engineering and computer sciences (EECS) with the University of California at Irvine Irvine CA USA. He is a coauthor of seven books. His research interests include embedded systems electronic design automation (EDA) computer architecture distributed systems healthcare Internet of Things (IoT) and brain-inspired architectures and computing.""Dr. Dutt is a Fellow of ACM. He was a recipient of the IFIP Silver Core Award. He has received numerous best paper awards. He serves as the Steering Committee Chair of the IEEE/ACM Embedded Systems Week (ESWEEK). He is also on the steering organizing and program committees of several premier EDA and embedded system design conferences and workshops. He has served on the Editorial Boards for the IEEE Transactions on Very Large Scale Integration (VLSI) Systems and the ACM Transactions on Embedded Computing Systems and also previously served as the Editor-in-Chief (EiC) for the ACM Transactions on Design Automation of Electronic Systems. He served on the Advisory Boards of the IEEE Embedded Systems Letters the ACM Special Interest Group on Embedded Systems the ACM Special Interest Group on Design Automationt and the ACM Transactions on Embedded Computing Systems. Carlo S. Regazzoni (Senior Member
IEEE) received the M.S. and Ph.D. degrees in electronic and telecommunications engineering from the University of Genoa Genoa Italy in 1987 and 1992 respectively.""He is currently a Full Professor of cognitive telecommunications systems with the Department of Electrical Electronics and Telecommunication Engineering and Naval Architecture (DITEN) University of Genoa and a Co-Ordinator of the Joint Doctorate on Interactive and Cognitive Environments (JDICE) international Ph.D. course started initially as EU Erasmus Mundus Project and
Autonomous systems are able to make decisions and potentially take actions without direct human intervention, which requires some knowledge about the system and its environment as well as goal-oriented reasoning. In c...
详细信息
Autonomous systems are able to make decisions and potentially take actions without direct human intervention, which requires some knowledge about the system and its environment as well as goal-oriented reasoning. In computersystems, one can derive such behavior from the concept of a rational agent with autonomy (“control over its own actions”), reactivity (“react to events from the environment”), proactivity (“act on its own initiative”), and sociality (“interact with other agents”) as fundamental properties \n[1]\n. Autonomous systems will undoubtedly pervade into our everyday lives, and we will find them in a variety of domains and applications including robotics, transportation, health care, communications, and entertainment to name a few. \nThe articles in this month’s special issue cover concepts and fundamentals, architectures and techniques, and applications and case studies in the exciting area of self-awareness in autonomous systems.
暂无评论