130,640 research outputs found
On the probability of undetected error for the maximum distance separable codes
The performance of maximum-distance-separable codes with symbols from GF(1) when they are used for pure error detection or for simultaneous error correction and detection is investigated. These codes are good for symbol error detection. Their probability of undetected error is upper bounded by q to the -r and decreases monotonically as the symbol error probability epsilon decreases from (q-1)/q to 0, where r is the number of parity-check symbols of a code
Coding for reliable satellite communications
This research project was set up to study various kinds of coding techniques for error control in satellite and space communications for NASA Goddard Space Flight Center. During the project period, researchers investigated the following areas: (1) decoding of Reed-Solomon codes in terms of dual basis; (2) concatenated and cascaded error control coding schemes for satellite and space communications; (3) use of hybrid coding schemes (error correction and detection incorporated with retransmission) to improve system reliability and throughput in satellite communications; (4) good codes for simultaneous error correction and error detection, and (5) error control techniques for ring and star networks
Ricci-flat graphs with girth at least five
A graph is called Ricci-flat if its Ricci-curvatures vanish on all edges.
Here we use the definition of Ricci-cruvature on graphs given in [Lin-Lu-Yau,
Tohoku Math., 2011], which is a variation of [Ollivier, J. Funct. Math., 2009].
In this paper, we classified all Ricci-flat connected graphs with girth at
least five: they are the infinite path, cycle (), the
dodecahedral graph, the Petersen graph, and the half-dodecahedral graph. We
also construct many Ricci-flat graphs with girth 3 or 4 by using the root
systems of simple Lie algebras.Comment: 14 pages, 15 figure
Diquarks, Pentaquarks and Dibaryons
We explore the connection between pentaquarks and dibaryons composed of three
diquarks in the framework of the diquark model. With the available experimental
data on H dibaryon, we estimate the Pauli blocking and annihilation effects and
constrain the pentaquark singlet mass. Using the
pentaquark mass, we estimate dibaryon mass
Recovering Dense Tissue Multispectral Signal from in vivo RGB Images
Hyperspectral/multispectral imaging (HSI/MSI) contains rich information
clinical applications, such as 1) narrow band imaging for vascular
visualisation; 2) oxygen saturation for intraoperative perfusion monitoring and
clinical decision making [1]; 3) tissue classification and identification of
pathology [2]. The current systems which provide pixel-level HSI/MSI signal can
be generally divided into two types: spatial scanning and spectral scanning.
However, the trade-off between spatial/spectral resolution, the acquisition
time, and the hardware complexity hampers implementation in real-world
applications, especially intra-operatively. Acquiring high resolution images in
real-time is important for HSI/MSI in intra-operative imaging, to alleviate the
side effect caused by breathing, heartbeat, and other sources of motion.
Therefore, we developed an algorithm to recover a pixel-level MSI stack using
only the captured snapshot RGB images from a normal camera. We refer to this
technique as "super-spectral-resolution". The proposed method enables recovery
of pixel-level-dense MSI signals with 24 spectral bands at ~11 frames per
second (FPS) on a GPU. Multispectral data captured from porcine bowel and
sheep/rabbit uteri in vivo has been used for training, and the algorithm has
been validated using unseen in vivo animal experiments.Comment: accepted by Hamlyn Symposium 201
- …