Results 11 - 20 of 6,597

On the capacity of MIMO broadcast channel with partial side information

by Masoud Sharif, Babak Hassibi - IEEE TRANS. INFORM. THEORY , 2005
"... In multiple-antenna broadcast channels, unlike point-to-point multiple-antenna channels, the multiuser capacity depends heavily on whether the transmitter knows the channel coefficients to each user. For instance, in a Gaussian broadcast channel with transmit antennas and single-antenna users, the ..."
Abstract - Cited by 349 (9 self) - Add to MetaCart
In multiple-antenna broadcast channels, unlike point-to-point multiple-antenna channels, the multiuser capacity depends heavily on whether the transmitter knows the channel coefficients to each user. For instance, in a Gaussian broadcast channel with transmit antennas and single-antenna users

Multicast-Based Inference of Network-Internal Characteristics: Accuracy of Packet Loss Estimation

by R. Caceres, N.G. Duffield, J. Horowitz, D. Towsley, T. Bu - IEEE Transactions on Information Theory , 1998
"... We explore the use of end-to-end multicast traffic as measurement probes to infer network-internal characteristics. We have developed in an earlier paper [2] a Maximum Likelihood Estimator for packet loss rates on individual links based on losses observed by multicast receivers. This technique explo ..."
Abstract - Cited by 323 (40 self) - Add to MetaCart
exploits the inherent correlation between such observations to infer the performance of paths between branch points in the multicast tree spanning the probe source and its receivers. We evaluate through analysis and simulation the accuracy of our estimator under a variety of network conditions

Accelerating Magnetic Resonance Imaging by Unifying Sparse Models and Multiple Receivers

by Daniel S. Weller, Vivek K. Goyal, Mnasisea T S Insttute, Daniel S. Weller , 2012
"... Magnetic resonance imaging (MRI) is an increasingly versatile diagnostic tool for a variety of medical purposes. During a conventional MRI scan, samples are acquired along a trajectory in the spatial Fourier transform domain (called k-space) and the image is reconstructed using an inverse discrete F ..."
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Fourier transform. The affordability, availability, and applications of MRI remain limited by the time required to sam-ple enough points of k-space for the desired field of view (FOV), resolution, and signal-to-noise ratio (SNR). GRAPPA, an accelerated parallel imaging method, and compressed sensing (CS

Action Recognition by Dense Trajectories

by Heng Wang , Alexander Kläser , Cordelia Schmid , Liu Cheng-lin , 2011
"... Feature trajectories have shown to be efficient for rep-resenting videos. Typically, they are extracted using the KLT tracker or matching SIFT descriptors between frames. However, the quality as well as quantity of these trajecto-ries is often not sufficient. Inspired by the recent success of dense ..."
Abstract - Cited by 293 (16 self) - Add to MetaCart
sampling in image classification, we propose an approach to describe videos by dense trajectories. We sam-ple dense points from each frame and track them based on displacement information from a dense optical flow field. Given a state-of-the-art optical flow algorithm, our trajec-tories are robust to fast

Particle-Based Fluid Simulation for Interactive Applications

by Matthias Müller, David Charypar, Markus Gross , 2003
"... Realistically animated fluids can add substantial realism to interactive applications such as virtual surgery simulators or computer games. In this paper we propose an interactive method based on Smoothed Particle Hydrodynamics (SPH) to simulate fluids with free surfaces. The method is an extension ..."
Abstract - Cited by 280 (11 self) - Add to MetaCart
, the particle-based approach makes mass conservation equations and convection terms dispensable which reduces the complexity of the simulation. In addition, the particles can directly be used to render the surface of the fluid. We propose methods to track and visualize the free surface using point splatting

A Static Analyzer for Large Safety-Critical Software

by Bruno Blanchet, Patrick Cousot, Radhia Cousot, Jerome Feret, Laurent Mauborgne, Antoine Mine, David Monniaux, Xavier Rival , 2003
"... We show that abstract interpretation-based static program analysis can be made e#cient and precise enough to formally verify a class of properties for a family of large programs with few or no false alarms. This is achieved by refinement of a general purpose static analyzer and later adaptation to p ..."
Abstract - Cited by 271 (54 self) - Add to MetaCart
We show that abstract interpretation-based static program analysis can be made e#cient and precise enough to formally verify a class of properties for a family of large programs with few or no false alarms. This is achieved by refinement of a general purpose static analyzer and later adaptation

Supervisory Control of Families of Linear Set-Point Controllers - Part 2: Robustness

by A. S. Morse - IEEE Trans. Automat. Contr , 1998
"... A simply-structured high-level controller called a `supervisor' has recently been proposed in [1] for the purpose of orchestrating the switching of a sequence of candidate set-point controllers into feedback with an imprecisely modeled siso process so as to cause the output of the process to ap ..."
Abstract - Cited by 234 (26 self) - Add to MetaCart
to approach and track a constant reference input. The process is assumed to be modeled by a siso linear system whose transfer function is in the union of a number of subclasses, each subclass being small enough so that one of the candidate controllers would solve the set-point tracking problem, were

Monitoring Corruption: Evidence from a Field Experiment in Indonesia

by Benjamin A. Olken - Journal of Political Economy , 2007
"... This paper uses a randomized field experiment to examine several approaches to reducing corruption. I measure missing expenditures in over 600 village road projects in Indonesia by having engineers independently estimate the prices and quantities of all inputs used in each road, and then comparing t ..."
Abstract - Cited by 261 (16 self) - Add to MetaCart
these estimates to villages ’ official expenditure reports. I find that announcing an increased probability of a government audit, from a baseline of 4 percent to 100 percent, reduced missing expenditures by about 8 percentage points, more than enough to make these audits cost-effective. By contrast, I find

Experimental evaluation of wireless simulation assumptions

by Calvin Newport, David Kotz, Yougu Yuan, Robert S. Gray, Jason Liu, Chip Elliott , 2004
"... All analytical and simulation research on ad hoc wireless networks must necessarily model radio propagation using simplifying assumptions. A growing body of research, however, indicates that the behavior of the protocol stack may depend significantly on these underlying assumptions. The standard res ..."
Abstract - Cited by 260 (12 self) - Add to MetaCart
response to this problem is a call for more realism in designing radio models. But how much realism is enough? This study is the first to approach this question by validating simulator performance (both at the physical and application layers) with the results of real-world data. Referencing an extensive

Centertrack: An IP overlay network for tracking DoS floods

by Robert Stone - In Proceedings of USENIX Security Symposium’2000 , 2000
"... Finding the source of forged Internet Protocol (IP) datagrams in a large, high-speed network is difficult due to the design of the IP protocol and the lack of sufficient capability in most high-speed, highcapacity router implementations. Typically, not enough of the routers in such a network are cap ..."
Abstract - Cited by 254 (0 self) - Add to MetaCart
Finding the source of forged Internet Protocol (IP) datagrams in a large, high-speed network is difficult due to the design of the IP protocol and the lack of sufficient capability in most high-speed, highcapacity router implementations. Typically, not enough of the routers in such a network
Results 11 - 20 of 6,597