Results 1 - 10 of 8,289

Attention and the detection of signals

by Michael I. Posner, Charles R. R. Snyder, Brian J. Davidson - Journal of Experimental Psychology: General , 1980
"... Detection of a visual signal requires information to reach a system capable of eliciting arbitrary responses required by the experimenter. Detection latencies are reduced when subjects receive a cue that indicates where in the visual field the signal will occur. This shift in efficiency appears to b ..."
Abstract - Cited by 565 (2 self) - Add to MetaCart
Detection of a visual signal requires information to reach a system capable of eliciting arbitrary responses required by the experimenter. Detection latencies are reduced when subjects receive a cue that indicates where in the visual field the signal will occur. This shift in efficiency appears

Earthquake Shakes Twitter Users: Real-time Event Detection by Social Sensors

by Takeshi Sakaki, Makoto Okazaki, Yutaka Matsuo - In Proceedings of the Nineteenth International WWW Conference (WWW2010). ACM , 2010
"... Twitter, a popular microblogging service, has received much attention recently. An important characteristic of Twitter is its real-time nature. For example, when an earthquake occurs, people make many Twitter posts (tweets) related to the earthquake, which enables detection of earthquake occurrence ..."
Abstract - Cited by 524 (4 self) - Add to MetaCart
of the numerous earthquakes and the large number of Twitter users throughout the country, we can detect an earthquake by monitoring tweets with high probability (96 % of earthquakes of Japan Meteorological Agency (JMA) seismic intensity scale 3 or more are detected). Our system detects earthquakes promptly

Predictive reward signal of dopamine neurons

by Wolfram Schultz - Journal of Neurophysiology , 1998
"... Schultz, Wolfram. Predictive reward signal of dopamine neurons. is called rewards, which elicit and reinforce approach behav-J. Neurophysiol. 80: 1–27, 1998. The effects of lesions, receptor ior. The functions of rewards were developed further during blocking, electrical self-stimulation, and drugs ..."
Abstract - Cited by 747 (12 self) - Add to MetaCart
environmental stimuli with appe- Despite their importance, rewards do not influence the brain titive value, predict and detect rewards and signal alerting and motivating events. By failing to discriminate between different

An Energy-Efficient MAC Protocol for Wireless Sensor Networks

by Wei Ye, John Heidemann, Deborah Estrin , 2002
"... This paper proposes S-MAC, a medium-access control (MAC) protocol designed for wireless sensor networks. Wireless sensor networks use battery-operated computing and sensing devices. A network of these devices will collaborate for a common application such as environmental monitoring. We expect senso ..."
Abstract - Cited by 1517 (36 self) - Add to MetaCart
sensor networks to be deployed in an ad hoc fashion, with individual nodes remaining largely inactive for long periods of time, but then becoming suddenly active when something is detected. These characteristics of sensor networks and applications motivate a MAC that is different from traditional

Medium Access Control with Coordinated Adaptive Sleeping for Wireless Sensor Networks

by Wei Ye, John Heidemann, Deborah Estrin - IEEE/ACM Transactions on Networking , 2004
"... This paper proposes S-MAC, a medium access control (MAC) protocol designed for wireless sensor networks. Wireless sensor networks use battery-operated computing and sensing devices. A network of these devices will collaborate for a common application such as environmental monitoring. We expect senso ..."
Abstract - Cited by 702 (15 self) - Add to MetaCart
sensor networks to be deployed in an ad hoc fashion, with nodes remaining largely inactive for long time, but becoming suddenly active when something is detected. These characteristics of sensor networks and applications motivate a MAC that is different from traditional wireless MACs such as IEEE 802

Implementation issues in spectrum sensing for cognitive radios

by Danijela Cabric, Shridhar Mubaraq Mishra, Robert W. Brodersen - in Proc. the 38th. Asilomar Conference on Signals, Systems, and Computers , 2004
"... Abstract- There are new system implementation challenges involved in the design of cognitive radios, which have both the ability to sense the spectral environment and the flexibility to adapt transmission parameters to maximize system capacity while co-existing with legacy wireless networks. The cri ..."
Abstract - Cited by 440 (7 self) - Add to MetaCart
. The critical design problem is the need to process multi-gigahertz wide bandwidth and reliably detect presence of primary users. This places severe requirements on sensitivity, linearity, and dynamic range of the circuitry in the RF front-end. To improve radio sensitivity of the sensing function through

Iterative (turbo) soft interference cancellation and decoding for coded CDMA

by Xiaodong Wang, H. Vincent Poor - IEEE Trans. Commun , 1999
"... Abstract — The presence of both multiple-access interference (MAI) and intersymbol interference (ISI) constitutes a major impediment to reliable communications in multipath code-division multiple-access (CDMA) channels. In this paper, an iterative receiver structure is proposed for decoding multiuse ..."
Abstract - Cited by 456 (18 self) - Add to MetaCart
. Moreover, at high signal-to-noise ratio, the detrimental effects of MAI and ISI in the channel can almost be completely overcome by iterative processing, and single-user performance can be approached. Index Terms — Coded CDMA, instantaneous MMSE filtering, multiuser detection, soft interference

Performance Anomaly of 802.11b

by Martin Heusse, Franck Rousseau, Gilles Berger-sabbatel, Andrzej Duda - In IEEE INFOCOM , 2003
"... Abstract — We analyze the performance of the IEEE 802.11b wireless local area networks. We have observed that when some mobile hosts use a lower bit rate than the others, the performance of all hosts is considerably degraded. Such a situation is a common case in wireless local area networks in which ..."
Abstract - Cited by 431 (11 self) - Add to MetaCart
in which a host far away from an Access Point is subject to important signal fading and interference. To cope with this problem, the host changes its modulation type, which degrades its bit rate to some lower value. Typically, 802.11b products degrade the bit rate from 11 Mb/s to 5.5, 2, or 1 Mb/s when

Linear multiuser detectors for synchronous code-division multiple-access channels

by Ruxandra Lupas, Sergio Verdú - IEEE TRANS. INFORM. THEORY , 1989
"... In code-division multiple-access systems, simultaneous mul-tiuser accessing of a common channel is made possible by assigning a signature waveform to each user. Knowledge of these waveforms enables the receiver to demodulate the data streams of each user, upon observation of the sum of the transmitt ..."
Abstract - Cited by 385 (4 self) - Add to MetaCart
of the transmitted signals, perturbed by additive noise. Under the assumptions of symbol-synchronous transmissions and white Gaussian noise, we analyze the detection mechanism at the receiver, comparing different detectors by their bit error rate in the low background noise region, and by their worst-case behavior

Ratio-Based Decisions and the Quantitative Analysis of cDNA Microarray Images

by Yidong Chen, Edward R. Dougherty, Michael L. Bittner , 1997
"... Gene expression can be quantitatively analyzed by hybridizing fluor-tagged mRNA to targets on a cDNA microarray. Comparison of gene expression levels arising from cohybridized samples is achieved by taking ratios of average expression levels for individual genes. A novel method of image segmentation ..."
Abstract - Cited by 366 (28 self) - Add to MetaCart
, and an iterative procedure for signal calibration is developed. 1997 Society of Photo-Optical Instrumentation Engineers. [S1083-3668(97)00504-2] Keywords cDNA; microarray; gene expression; image segmentation; Mann--Whitney target detection; ratio density, ratio confidence interval.
Results 1 - 10 of 8,289