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Dynamic variations in the

by unknown authors
"... Dynamic variations in the ultrasound greyscale median of carotid artery plaques Kanber et al. ..."
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Dynamic variations in the ultrasound greyscale median of carotid artery plaques Kanber et al.

End-to-End Internet Packet Dynamics,”

by Vern Paxson - Proc. SIGCOMM '97, , 1997
"... Abstract We discuss findings from a large-scale study of Internet packet dynamics conducted by tracing 20,000 TCP bulk transfers between 35 Internet sites. Because we traced each 100 Kbyte transfer at both the sender and the receiver, the measurements allow us to distinguish between the end-to-end ..."
Abstract - Cited by 843 (19 self) - Add to MetaCart
Abstract We discuss findings from a large-scale study of Internet packet dynamics conducted by tracing 20,000 TCP bulk transfers between 35 Internet sites. Because we traced each 100 Kbyte transfer at both the sender and the receiver, the measurements allow us to distinguish between the end

NeXt generation/dynamic spectrum access/cognitive Radio Wireless Networks: A Survey

by Ian F. Akyildiz, Won-Yeol Lee, Mehmet C. Vuran, Shantidev Mohanty - COMPUTER NETWORKS JOURNAL (ELSEVIER , 2006
"... Today's wireless networks are characterized by a fixed spectrum assignment policy. However, a large portion of the assigned spectrum is used sporadically and geographical variations in the utilization of assigned spectrum ranges from 15% to 85% with a high variance in time. The limited availabl ..."
Abstract - Cited by 746 (15 self) - Add to MetaCart
Today's wireless networks are characterized by a fixed spectrum assignment policy. However, a large portion of the assigned spectrum is used sporadically and geographical variations in the utilization of assigned spectrum ranges from 15% to 85% with a high variance in time. The limited

Receiver-driven Layered Multicast

by Steven McCanne, Van Jacobson, Martin Vetterli , 1996
"... State of the art, real-time, rate-adaptive, multimedia applications adjust their transmission rate to match the available network capacity. Unfortunately, this source-based rate-adaptation performs poorly in a heterogeneous multicast environment because there is no single target rate — the conflicti ..."
Abstract - Cited by 737 (22 self) - Add to MetaCart
as well as dynamic variations in network capacity (i.e., congestion). We describe the RLM protocol and evaluate its performance with a preliminary simulation study that characterizes user-perceived quality by assessing loss rates over multiple time scales. For the configurations we simulated, RLM results

Variational algorithms for approximate Bayesian inference

by Matthew J. Beal , 2003
"... The Bayesian framework for machine learning allows for the incorporation of prior knowledge in a coherent way, avoids overfitting problems, and provides a principled basis for selecting between alternative models. Unfortunately the computations required are usually intractable. This thesis presents ..."
Abstract - Cited by 440 (9 self) - Add to MetaCart
a unified variational Bayesian (VB) framework which approximates these computations in models with latent variables using a lower bound on the marginal likelihood. Chapter 1 presents background material on Bayesian inference, graphical models, and propaga-tion algorithms. Chapter 2 forms

An Adaptive Energy-Efficient MAC Protocol for Wireless Sensor Networks

by Tijs van Dam, Koen Langendoen - SENSYS'03 , 2003
"... In this paper we describe T-MAC, a contention-based Medium Access Control protocol for wireless sensor networks. Applications for these networks have some characteristics (low message rate, insensitivity to latency) that can be exploited to reduce energy consumption by introducing an active/sleep du ..."
Abstract - Cited by 534 (13 self) - Add to MetaCart
/sleep duty cycle. To handle load variations in time and location T-MAC introduces an adaptive duty cycle in a novel way: by dynamically ending the active part of it. This reduces the amount of energy wasted on idle listening, in which nodes wait for potentially incoming messages, while still maintaining a

Cognitive Radio: Brain-Empowered Wireless Communications

by Simon Haykin , 2005
"... Cognitive radio is viewed as a novel approach for improving the utilization of a precious natural resource: the radio electromagnetic spectrum. The cognitive radio, built on a software-defined radio, is defined as an intelligent wireless communication system that is aware of its environment and use ..."
Abstract - Cited by 1541 (4 self) - Add to MetaCart
and uses the methodology of understanding-by-building to learn from the environment and adapt to statistical variations in the input stimuli, with two primary objectives in mind: • highly reliable communication whenever and wherever needed; • efficient utilization of the radio spectrum. Following

Comparison of parametric representations for monosyllabic word recognition in continuously spoken sentences

by Steven B. Davis, Paul Mermelstein - ACOUSTICS, SPEECH AND SIGNAL PROCESSING, IEEE TRANSACTIONS ON , 1980
"... Several parametric representations of the acoustic signal were compared as to word recognition performance in a syllable-oriented continuous speech recognition system. The vocabulary in-cluded many phonetically similar monosyllabic words, therefore the emphasis was on ability to retain phonetically ..."
Abstract - Cited by 1120 (2 self) - Add to MetaCart
phonetically significant acoustic information in the face of syntactic and duration variations. For each ~ arameter set (based on a mel-frequency cepstrum, a linear frequency cepstrum, a linear prediction cepstrum, a linear predic-tion spectrum, or a set of reflection coefficients), word templates were

Featherweight Java: A Minimal Core Calculus for Java and GJ

by Atsushi Igarashi, Benjamin C. Pierce, Philip Wadler - ACM Transactions on Programming Languages and Systems , 1999
"... Several recent studies have introduced lightweight versions of Java: reduced languages in which complex features like threads and reflection are dropped to enable rigorous arguments about key properties such as type safety. We carry this process a step further, omitting almost all features of the fu ..."
Abstract - Cited by 659 (23 self) - Add to MetaCart
computational “feel, ” providing classes, methods, fields, inheritance, and dynamic typecasts with a semantics closely following Java’s. A proof of type safety for Featherweight Java thus illustrates many of the interesting features of a safety proof for the full language, while remaining pleasingly compact

Modeling and Forecasting Realized Volatility

by Torben G. Andersen, Tim Bollerslev, Francis X. Diebold, Paul Labys , 2002
"... this paper is built. First, although raw returns are clearly leptokurtic, returns standardized by realized volatilities are approximately Gaussian. Second, although the distributions of realized volatilities are clearly right-skewed, the distributions of the logarithms of realized volatilities are a ..."
Abstract - Cited by 549 (50 self) - Add to MetaCart
are approximately Gaussian. Third, the long-run dynamics of realized logarithmic volatilities are well approximated by a fractionally-integrated long-memory process. Motivated by the three ABDL empirical regularities, we proceed to estimate and evaluate a multivariate model for the logarithmic realized volatilities
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