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A Locally Adaptive Data Compression Scheme
, 1986
"... A data compression scheme that exploits locality of reference, such as occurs when words are used frequently over short intervals and then fall into long periods of disuse, is described. The scheme is based on a simple heuristic for selforganizing sequential search and on variablelength encoding ..."
Abstract

Cited by 169 (2 self)
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A data compression scheme that exploits locality of reference, such as occurs when words are used frequently over short intervals and then fall into long periods of disuse, is described. The scheme is based on a simple heuristic for selforganizing sequential search and on variablelength encodings of integers. We prove that it never performs much worse than Huffman coding and can perform substantially better; experiments on real files show that its performance is usually quite close to that of Huffman coding. Our scheme has many implementation advantages: it is simple, allows fast encoding and decoding, and requires only one pass over the data to be compressed (static Huffman coding takes two passes).
Fishspear: A Priority Queue Algorithm (Extended Abstract)
"... The Fishspear priority queue algorithm is presented and analyzed. Fishspear makes fewer than 80 % as many comparisons as heaps in the worst case, and its relative performance is even better in many common situations. The code itself embodies an unusual recursive structure which permits highly dynami ..."
Abstract

Cited by 15 (1 self)
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The Fishspear priority queue algorithm is presented and analyzed. Fishspear makes fewer than 80 % as many comparisons as heaps in the worst case, and its relative performance is even better in many common situations. The code itself embodies an unusual recursive structure which permits highly dynamic and datadependent execution. Fishspear also differs from heaps in that it can be implemented efficiently using sequential storage such as stacks or tapes, making it possibly attractive for implementation of very large queues on paged memory systems. (Details of the implementation are deferred to the full paper.)
On Consulting a Set of Experts and Searching
, 1996
"... Two chapters of this thesis analyze expert consulting problems via game theoretic models; the first points out a close connection between the problem of consulting a set of experts and the problem of searching. The last chapter presents a solution to the dictionary problem of supporting and update ( ..."
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Two chapters of this thesis analyze expert consulting problems via game theoretic models; the first points out a close connection between the problem of consulting a set of experts and the problem of searching. The last chapter presents a solution to the dictionary problem of supporting and update (Insert and Delete) operations on a set of key values. The first chapter shows...
unknown title
"... A composite object represented as a directed graph (digraph for short) is an important data structure that requires efficient support in CAD/CAM, CASE, office systems, software management, web databases, and document databases. It is cumbersome to handle such objects in relational database systems w ..."
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A composite object represented as a directed graph (digraph for short) is an important data structure that requires efficient support in CAD/CAM, CASE, office systems, software management, web databases, and document databases. It is cumbersome to handle such objects in relational database systems when they involve ancestordescendant relationships (or say, recursive relationships). In this paper, we present a new encoding method to label a digraph, which reduces the footprints of all previous strategies. This method is based on a tree labeling method and the concept of branchings that are used in graph theory for finding the shortest connection networks. A branching is a subgraph of a given digraph that is in fact a forest, but covers all the nodes of the graph. On the one hand, the proposed encoding scheme achieves the smallest space requirements among all previously published strategies for recognizing recursive relationships. On the other hand, it leads to a new algorithm for computing transitive closures for DAGs (directed acyclic graph) in O(e⋅b) time and O(n⋅b) space, where n represents the number of the nodes of a DAG, e the numbers of the edges, and b the DAG’s breadth. The method can also be extended to graphs containing cycles. Especially, based on this encoding method, a multilevel compression is developed, by means of which the space for the representation of a transitive closure can be reduced to O((b/d k)⋅n), where k is the number of compression levels and d is the average outdegree of the nodes.