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Information Retrieval Through Hybrid Navigation of Lattice Representations
, 1996
"... In this paper we present a comprehensive approach to automatic organization and hybrid navigation of text databases. An organizing stage first builds a particular lattice representation of the data, through text indexing followed by lattice clustering of the indexed texts. The lattice representation ..."
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Cited by 15 (4 self)
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In this paper we present a comprehensive approach to automatic organization and hybrid navigation of text databases. An organizing stage first builds a particular lattice representation of the data, through text indexing followed by lattice clustering of the indexed texts. The lattice representation, then, supports the navigation stage of the system, a visual retrieval interface that combines three main retrieval strategies: browsing, querying, and bounding. Browsing and querying are used to search the retrieval space, bounding is used to restrict it based on the information that users have, or get during their interaction with the system. We show that such a hybrid paradigm permits high flexibility in trading off information exploration and retrieval and, in addition, has good retrieval performance. We compared information retrieval using latticebased hybrid navigation with conventional Boolean querying. The results of an experiment conducted on two mediumsized bibliographic databases showed that the performance of lattice retrieval was comparable to or better than Boolean retrieval
ULYSSES: A Latticebased Multiple Interaction Strategy Retrieval Interface
 In Blumenthal et al., HumanComputer Interaction
, 1995
"... We present a twostage system for information exploration and retrieval. The first stage, named GALOIS, organizes the information contained into a database into a particular lattice structure; the second stage, named ULYSSES, is a visual interface to access the structure built in the earlier sta ..."
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Cited by 12 (3 self)
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We present a twostage system for information exploration and retrieval. The first stage, named GALOIS, organizes the information contained into a database into a particular lattice structure; the second stage, named ULYSSES, is a visual interface to access the structure built in the earlier stage. In this paper we focus on the latter. ULYSSES is based on a tight integration of traditional and novel user interaction paradigms that can be seen as a search&bound approach to information retrieval. The user may search the retrieval space by browsing or querying, but he or she may also bound the retrieval space by specifying constraints that the information contained in it has to satisfy. These interaction modes can be naturally combined to produce a hybrid retrieval strategy that best reflects the user goals and his/her domain knowledge. The retrieval effectiveness of our system has been tested in an experiment on subject searching where it compared favourably with respect to a Boolean retrieval system.
Systolic Processing For Dynamic Programming Problems
, 1988
"... In this paper we investigate systolic processing for problems formulated in dynamic programming. These problems are classified as monadicserial, polyadicserial, monadicnonserial, and polyadicnonserial. Problems in serial formulations can be implemented easily in systolic arrays; however, nonseria ..."
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Cited by 9 (0 self)
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In this paper we investigate systolic processing for problems formulated in dynamic programming. These problems are classified as monadicserial, polyadicserial, monadicnonserial, and polyadicnonserial. Problems in serial formulations can be implemented easily in systolic arrays; however, nonserial problems may have to be transformed into a serial one before an efficient implementation can be found. A monadicserial dynamic programming problem can be solved as the search of an optimal path in a multistage graph and can be computed as a string of matrix multiplications. Three efficient systolicarray designs are presented. A polyadicserial dynamic programming problem can be solved by either a divideandconquer algorithm or the search of optimal solutions in a serial AND/ORgraph. We have evaluated the asymptotically optimal architecture for divideandconquer algorithms and have developed efficient methods of mapping a regular AND/ORgraph into systolic arrays. Cases are studied for transforming a problem in a nonserial formula tion into a serial one.
A General Heuristic Bottomup Procedure for Searching AND/OR Graphs VIPIN KUMAR
"... This paper presents a general heuristic bottomup procedure for finding a leastcost solution tree of an AND/OR graph when the cost functions associated with the arcs are monotone. Since monotone cost functions are very general, the procedure is applicable to a very large number of problems. The pro ..."
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This paper presents a general heuristic bottomup procedure for finding a leastcost solution tree of an AND/OR graph when the cost functions associated with the arcs are monotone. Since monotone cost functions are very general, the procedure is applicable to a very large number of problems. The procedure works for both cyclic and acyclic AND/OR graphs, and subsumes most of the known bottomup procedures for searching AND/OR graphs. Many statespace search procedures and dynamic programming procedures are also special cases of this procedure. 1.
THE COMPLEXITY OF SEARCHING SEVERAL CLASSES OF AND/OR GRAPHS
"... The complexity of searching for a minimum cost solution graph of an AND/OR graph is analyzed for the class of AND/OR graphs repreaentable by a context free grammar with coat functions; finding a minimum coat solution graph ia then equivalent to finding a lowest coat derivation. Several classes of se ..."
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The complexity of searching for a minimum cost solution graph of an AND/OR graph is analyzed for the class of AND/OR graphs repreaentable by a context free grammar with coat functions; finding a minimum coat solution graph ia then equivalent to finding a lowest coat derivation. Several classes of search problems are defined, based on properties of the cost functions and grammar. We show that certain of these classes have different, search complexities specifically, we show that there are distinct classes for which the complexity of finding a minimum cost solution graph is nonrecursive, exponential, NPcomplete, and Q(n 2), where n ia the size of the grammar representing the problem. The correspondence between problem structure and search complexity may serve as a guide for modeling real problems