Results 1  10
of
89
Expander Codes
 IEEE TRANSACTIONS ON INFORMATION THEORY
, 1996
"... We present a new class of asymptotically good, linear errorcorrecting codes based upon expander graphs. These codes have linear time sequential decoding algorithms, logarithmic time parallel decoding algorithms with a linear number of processors, and are simple to understand. We present both random ..."
Abstract

Cited by 290 (9 self)
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We present a new class of asymptotically good, linear errorcorrecting codes based upon expander graphs. These codes have linear time sequential decoding algorithms, logarithmic time parallel decoding algorithms with a linear number of processors, and are simple to understand. We present both randomized and explicit constructions for some of these codes. Experimental results demonstrate the extremely good performance of the randomly chosen codes.
Reasoning about Qualitative Temporal Information
 Artificial Intelligence
, 1992
"... Representing and reasoning about incomplete and indefinite qualitative temporal information is an essential part of many artificial intelligence tasks. An intervalbased framework and a pointbased framework have been proposed for representing such temporal information. In this paper, we address ..."
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Cited by 144 (5 self)
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Representing and reasoning about incomplete and indefinite qualitative temporal information is an essential part of many artificial intelligence tasks. An intervalbased framework and a pointbased framework have been proposed for representing such temporal information. In this paper, we address two fundamental reasoning tasks that arise in applications of these frameworks: Given possibly indefinite and incomplete knowledge of the relationships between some intervals or points, (i) find a scenario that is consistent with the information provided, and (ii) find the feasible relations between all pairs of intervals or points. For the pointbased framework and a restricted version of the intervalbased framework, we give computationally efficient procedures for finding a consistent scenario and for finding the feasible relations. Our algorithms are marked improvements over the previously known algorithms. In particular, we develop an O(n 2 ) time algorithm for finding one co...
Lineartime Encodable and Decodable ErrorCorrecting Codes
, 1996
"... We present a new class of asymptotically good, linear errorcorrecting codes. These codes can be both encoded and decoded in linear time. They can also be encoded by logarithmicdepth circuits of linear size and decoded by logarithmic depth circuits of size 0 (n log n). We present both randomized an ..."
Abstract

Cited by 122 (5 self)
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We present a new class of asymptotically good, linear errorcorrecting codes. These codes can be both encoded and decoded in linear time. They can also be encoded by logarithmicdepth circuits of linear size and decoded by logarithmic depth circuits of size 0 (n log n). We present both randomized and explicit constructions of these codes.
Transducers and repetitions
 Theoretical Computer Science
, 1986
"... Abstract. The factor transducer of a word associates to each of its factors (or subwc~rds) their first occurrence. Optimal bounds on the size of minimal factor transducers together with an algorithm for building them are given. Analogue results and a simple algorithm are given for the case of subseq ..."
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Cited by 90 (17 self)
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Abstract. The factor transducer of a word associates to each of its factors (or subwc~rds) their first occurrence. Optimal bounds on the size of minimal factor transducers together with an algorithm for building them are given. Analogue results and a simple algorithm are given for the case of subsequential suffix transducers. Algorithms are applied to repetition searching in words. Rl~sum~. Le transducteur des facteurs d'un mot associe a chacun de ses facteurs leur premiere occurrence. On donne des bornes optimales sur la taille du transducteur minimal d'un mot ainsi qu'un algorithme pour sa construction. On donne des r6sultats analogues et un algorithme simple dans le cas du transducteur souss~luentiel des suffixes d'un mot. On donne une application la d6tection de r6p6titions dans les mots. Contents
On the Complexity of Sphere Decoding in Digital Communications
 IN DIGITAL COMMUNICATIONS,” IEEE TRANSACTIONS ON SIGNAL PROCESSING, TO APPEAR
, 2005
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On the exponent of the all pairs shortest path problem
"... The upper bound on the exponent, ω, of matrix multiplication over a ring that was three in 1968 has decreased several times and since 1986 it has been 2.376. On the other hand, the exponent of the algorithms known for the all pairs shortest path problem has stayed at three all these years even for t ..."
Abstract

Cited by 73 (2 self)
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The upper bound on the exponent, ω, of matrix multiplication over a ring that was three in 1968 has decreased several times and since 1986 it has been 2.376. On the other hand, the exponent of the algorithms known for the all pairs shortest path problem has stayed at three all these years even for the very special case of directed graphs with uniform edge lengths. In this paper we give an algorithm of time O � n ν log 3 n � , ν = (3 + ω)/2, for the case of edge lengths in {−1, 0, 1}. Thus, for the current known bound on ω, we get a bound on the exponent, ν < 2.688. In case of integer edge lengths with absolute value bounded above by M, the time bound is O � (Mn) ν log 3 n � and the exponent is less than 3 for M = O(n α), for α < 0.116 and the current bound on ω.
OnTheFly Detection of Access Anomalies
 In Proceedings of the SIGPLAN 1989 Conference on Programming Language Design and Implementation
, 1998
"... Access anomalies are a common class of bugs in sharedmemory parallel programs. An access anomaly occurs when two concurrent execution threads both write (or one thread reads and the other writes) the same shared memory location. Approaches to the detection of access anomalies include static analysi ..."
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Cited by 71 (0 self)
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Access anomalies are a common class of bugs in sharedmemory parallel programs. An access anomaly occurs when two concurrent execution threads both write (or one thread reads and the other writes) the same shared memory location. Approaches to the detection of access anomalies include static analysis, postmortem trace analysis, and onthe fly monitoring. A general onthefly algorithm for access anomaly detection is presented, which can be applied to programs with both nested forkjoin and synchronization operations. The advantage of onthefly detection over postmortem analysis is that the amount of storage used can be greatly reduced by data compression techniques and by discarding information as soon as it becomes obsolete. In the algorithm presented, the amount of storage required at any time depends only on the number V of shared variables being monitored and the number N of threads, not on the number of synchronizations. Data compression is achieved by the use of two techniques...
Curve reconstruction from unorganized points
 Computer Aided Geometric Design
, 2000
"... We present an algorithm to approximate a set of unorganized points with a simple curve without selfintersections. The moving leastsquares method has a good ability to reduce a point cloud to a thin curvelike shape which is a nearbest approximation of the point set. In this paper, an improved mov ..."
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Cited by 55 (3 self)
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We present an algorithm to approximate a set of unorganized points with a simple curve without selfintersections. The moving leastsquares method has a good ability to reduce a point cloud to a thin curvelike shape which is a nearbest approximation of the point set. In this paper, an improved moving leastsquares technique is suggested using Euclidean minimum spanning tree, region expansion and refining iteration. After thinning a given point cloud using the improved moving leastsquares technique we can easily reconstruct a smooth curve. As an application, a pipe surface reconstruction algorithm is presented.