1225370
The Impact of NBTI on the Performance of Combinational and Sequential Circuits
Negative-bias-temperature-instability (NBTI) has become the primary limiting factor of circuit lifetime. In this work, we develop a general framework for analyzing the impact of NBTI on the performance of a circuit, based on various circuit parameters such as the supply voltage, temperature, and node switching activity of the signals etc. We propose an efficient method to predict the degradation of circuit performance based on circuit topology and the switching activity of the signals over long periods of time. We demonstrate our results on ISCAS benchmarks and a 65 nm industrial design. The framework is used to provide key design insights for designing reliable circuits. The key design insights that we obtain are: (1) degradation due to NBTI is most sensitive on the input patterns and the duty cycle; the difference in the delay degradation can be up to 5X for various static and dynamic conditions, (2) during dynamic operation, NBTI-induced degradation is relatively insensitive to supply voltage, but strongly dependent on temperature; (3) NBTI has marginal impact on the clock signal.
10919497
SRAM leakage suppression by minimizing standby supply voltage
Suppressing the leakage current in memories is critical in low-power design. By reducing the standby supply voltage (V/sub DD/) to its limit, which is the data retention voltage (DRV), leakage power can be substantially reduced. This paper explores how low DRV can be in a standard low leakage SRAM module and analyzes how DRV is affected by parameters such as process variations, chip temperature, and transistor sizing. An analytical model for DRV as a function of process and design parameters is presented, and forms the basis for further design space explorations. This model is verified using simulations as well as measurements from a 4 kB SRAM chip in a 0.13 /spl mu/m technology. It is demonstrated that an SRAM cell state can be preserved at sub-300 mV standby VDD, with more than 90% leakage power savings.
11588495
SRAM Cell Optimization for Ultra-Low Power Standby
This paper proposes a comprehensive SRAM cell optimization scheme that minimizes leakage power under ultra-low standby supply voltage (VDD). The theoretical limit of data retention voltage (DRV), the minimum VDD that preserves the states of a memory cell, was derived to be 50 mV for an industrial 90 nm technology. A DRV design model was developed on parameters including body bias, sizing, and channel length. A test chip was implemented and measured to attain DRV sensitivities to key design parameters. Based on this, a low-leakage SRAM cell design methodology is derived and the feasibility of a 270 mV standby VDD was demonstrated, including a safety margin of 100 mV. As a result, the SRAM leakage power was reduced by 97%.
6475869
Modeling and minimization of PMOS NBTI effect for robust nanometer design
Negative bias temperature instability (NBTI) has become the dominant reliability concern for nanoscale PMOS transistors. In this paper, a predictive model is developed for the degradation of NBTI in both static and dynamic operations. Model scalability and generality are comprehensively verified with experimental data over a wide range of process and bias conditions. By implementing the new model into SPICE for an industrial 90nm technology, key insights are obtained for the development of robust design solutions: (1) the most effective techniques to mitigate the NBTI degradation are VDD tuning, PMOS sizing, and reducing the duty cycle; (2) an optimal VDD exists to minimize the degradation of circuit performance; (3) tuning gate length or the switching frequency has little impact on the NBTI effect; (4) a new switching scenario is identified for worst case timing analysis during NBTI stress
6260783
Style components
We propose a novel method for interactive editing of motion data based on motion decomposition. Our method employs Independent Component Analysis (ICA) to separate motion data into visually meaningful components called style components. The user then interactively identifies suitable style components and manipulates them based on a proposed set of operations. In particular, the user can transfer style components from one motion to another in order to create new motions that retain desirable aspects of the style and expressiveness of the original motion. For example, a clumsy walking motion can be decomposed so as to separate the clumsy nature of the motion from the underlying walking pattern. The clumsy style component can then be applied to a running motion, which will then yield a clumsy-looking running motion. Our approach is simple, efficient and intuitive since the components are themselves motion data. We demonstrate that the proposed method can serve as an effective tool for interactive motion analysis and editing.
8145594
Effects of global interconnect optimizations on performance estimation of deep submicron design
In this paper, we quantify the impact of global interconnect optimization techniques that address such design objectives as delay, peak noise, delay uncertainty due to noise, power, and cost. In doing so, we develop a new system-performance simulation model as a set of studies within the MARCO GSRC Technology Extrapolation (GTX) system. We model a typical point-to-point global interconnect and focus on accurate assessment of both circuit and design technology with respect to such issues as inductance, signal line shielding, dynamic delay, buffer placement uncertainty and repeater staggering. We demonstrate, for example, that optimal wire sizing models need to consider inductive effects-and that use of more accurate (-1,3) worst-case capacitive coupling noise switch factors substantially increases peak noise estimates compared to traditional (0,2) bounds. We also find that optimal repeater sizes are significantly smaller than conventional models would suggest, especially when considering energy-delay issues.
19011643
Total-Order Planning with Partially Ordered Subtasks
One of the more controversial recent planning algorithms is the SHOP algorithm, an HTN planning algorithm that plans for tasks in the same order that they are to be executed. SHOP can use domaindependent knowledge to generate plans very quickly, but it can be difficult to write good knowledge bases for SHOP. 
 
Our hypothesis is that this difficulty is because SHOP's total-ordering requirement for the subtasks of its methods is more restrictive than it needs to be. To examine this hypothesis, we have developed a new HTN planning algorithm called SHOP2. Like SHOP, SHOP2 is sound and complete, and it constructs plans in the same order that they will later be executed. But unlike SHOP, SHOP2 allows the subtasks of each method to be partially ordered. 
 
Our experimental results suggest that in some problem domains, the difficulty of writing SHOP knowledge bases derives from SHOP's total-ordering requirement--and that in such cases, SHOP2 can plan as efficiently as SHOP using knowledge bases simpler than those needed by SHOP.
13444952
Expressive speech-driven facial animation
Speech-driven facial motion synthesis is a well explored research topic. However, little has been done to model expressive visual behavior during speech. We address this issue using a machine learning approach that relies on a database of speech-related high-fidelity facial motions. From this training set, we derive a generative model of expressive facial motion that incorporates emotion control, while maintaining accurate lip-synching. The emotional content of the input speech can be manually specified by the user or automatically extracted from the audio signal using a Support Vector Machine classifier.
2266938
Cooperative Mobile Robotics: Antecedents and Directions
There has been increased research interest in systems composed of multiple autonomous mobile robots exhibiting cooperative behavior. Groups of mobile robots are constructed, with an aim to studying such issues as group architecture, resource conflict, origin of cooperation, learning, and geometric problems. As yet, few applications of cooperative robotics have been reported, and supporting theory is still in its formative stages. In this paper, we give a critical survey of existing works and discuss open problems in this field, emphasizing the various theoretical issues that arise in the study of cooperative robotics. We describe the intellectual heritages that have guided early research, as well as possible additions to the set of existing motivations.