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The PH-tree

Tilmann Zäschke, Christoph Zimmerli, Moira C. Norrie
2014 Proceedings of the 2014 ACM SIGMOD international conference on Management of data - SIGMOD '14  
We propose the PATRICIA-hypercube-tree, or PH-tree, a multi-dimensional data storage and indexing structure. It is based on binary PATRICIA-tries combined with hypercubes for efficient data access.  ...  We explain the concept of the PH-tree and demonstrate the performance of a sample implementation on various datasets and compare it to other spatial indices such as the kD-tree.  ...  Stefania Leone, who provided valuable feedback and support on early versions of this paper. This research was partially funded by the Hasler Foundation, Switzerland.  ... 
doi:10.1145/2588555.2588564 dblp:conf/sigmod/ZaschkeZN14 fatcat:xve6ueaekrhmhedcprdyi7ymfq

B-trees with lazy parent split

Yannis Manolopoulos
1994 Information Sciences  
A B-tree variant that postpones parent node splittings due to upcoming items until a later access of the same node is examined.  ...  It is shown that this technique substantially improves the performance of small degree B-trees so that, indeed, concurrency is enhanced.  ...  Note also that a consequence of data compactness is improved tree search performance 1141.  ... 
doi:10.1016/0020-0255(94)90040-x fatcat:uwifr7tk5zffzkcaeavn6hqmoy

Expansion of layouts of complete binary trees into grids

Y.-B. Lin, Z. Miller, M. Perkel, D. Pritikin, I.H. Sudborough
2003 Discrete Applied Mathematics  
That is, we give e cient layouts of complete binary trees into square grids, making improvements upon the previous work of others.  ...  Let T h be the complete binary tree of height h. Let M be the inÿnite grid graph with vertex set Z 2 , where two vertices (x1; y1) and (x2; y2) of M are adjacent if and only if |x1−x2|+|y1−y2|=1.  ...  We consider one-to-one, congestion one embeddings f of complete binary trees into two-dimensional grids and extended two-dimensional grids.  ... 
doi:10.1016/s0166-218x(02)00550-4 fatcat:vfaabouaabcjxfaaxhdejm5qpm

B-slack trees: Highly Space Efficient B-trees [article]

Trevor Brown
2017 arXiv   pre-print
B-slack trees, a subclass of B-trees that have substantially better worst-case space complexity, are introduced. They store $n$ keys in height $O(\log_b n)$, where $b$ is the maximum node degree.  ...  I would like thank my supervisor Faith Ellen for her helpful comments on this work, and for encouraging me to return to solutions that I had abandoned too quickly.  ...  No compactness preserving insertion or deletion procedures are known. The authors suggested using regular B-tree updates and periodically compacting a data structure to improve efficiency.  ... 
arXiv:1712.05020v2 fatcat:wlb5c6ktvjh6piyun6vfz36gvu

Frequent tree pattern mining: A survey

Aída Jiménez, Fernando Berzal, Juan-Carlos Cubero
2010 Intelligent Data Analysis  
Optionally, a tree can also have a predefined root, v 0 , and a binary ordering relationship defined over its nodes (i.e. ' ' ⊆ V × V ).  ...  Example dataset with different kinds of rooted trees (from left to right): (a) completely-ordered tree, (b) and (c) partially-ordered trees, (d) completely-unordered tree.  ...  It employs a specialized data structure, a Frequent-Subtree Forest or FST-Forest, that is used to represent frequent trees in a compact form and improve the efficiency of the support counting phase.  ... 
doi:10.3233/ida-2010-0443 fatcat:qyjf35zhijahdidz6rg4s7exiu

EUCALYPT: efficient tree reconciliation enumerator

Beatrice Donati, Christian Baudet, Blerina Sinaimeri, Pierluigi Crescenzi, Marie-France Sagot
2015 Algorithms for Molecular Biology  
We give an example where, for two pairs of host-parasite trees having each less than 41 leaves, the number of solutions is 5120, even when only time-feasible ones are kept.  ...  Only two algorithms currently exist that attempt such enumeration; in one case not all possible solutions are produced while in the other not all cost vectors are currently handled.  ...  In particular, the DTL model is a special case when the species tree is binary. However, the algorithm imposes some restrictions on the cost values.  ... 
doi:10.1186/s13015-014-0031-3 pmid:25648467 pmcid:PMC4310143 fatcat:j5dhp4ek5rfehjiq42oazodepu

AdaptiviTree: Adaptive Tree Visualization for Tournament-Style Brackets

D.S. Tan, G. Smith, Bongshin Lee, G.G. Robertson
2007 IEEE Transactions on Visualization and Computer Graphics  
AdaptiviTree not only provides a more compact and understandable representation, but also allows overlays that display predictions as well as other statistics.  ...  In this paper, we present AdaptiviTree, a novel visualization that adaptively deforms the representation of the tree and uses its shape to convey outcome information.  ...  Chitsaz, Adam Eversole, and Gavin Jancke for their assistance building the deployment prototype; Tom Cohen, Jeff Johnson, Steve Lee, Mike Pendergraft, Krishna Veermachaneni, and the MSN team for providing access  ... 
doi:10.1109/tvcg.2007.70537 pmid:17968054 fatcat:ivvvipbaazcp5gp54dz24u5deq

Fast Approximate Max-n Monte Carlo Tree Search for Ms Pac-Man

Spyridon Samothrakis, David Robles, Simon Lucas
2011 IEEE Transactions on Computational Intelligence and AI in Games  
We approached the problem by performing Monte-Carlo tree searches on a 5 player max n tree representation of the game with limited tree search depth.  ...  Performance-wise, our approach gets excellent scores, outperforming previous non-MCTS opponent approaches to the game by up to two orders of magnitude.  ...  This function assigns the binary value of one to a certain node in the tree path, and leaves the rest of the tree to zero.  ... 
doi:10.1109/tciaig.2011.2144597 fatcat:lfl3keghyjaaxayo7dj55jbyie

Linear Time Universal Coding and Time Reversal of Tree Sources Via FSM Closure

A. Martin, G. Seroussi, M.J. Weinberger
2004 IEEE Transactions on Information Theory  
Since much of the emphasis is on sequentiality, the two-pass approach of [10], in which the best model structure in a hierarchy (e.g., a tree) is estimated and described to the decoder in a first pass,  ...  This result answers the above motivating question in the affirmative. * Internal Accession Date Only To be published in IEEE Transactions on Information Theory Approved for External Publication Abstract  ...  For instance Verify(cbacb) leads to successive creations of nodes bacb, acb, cb and b, the latter two causing the split of previously traversed edges.  ... 
doi:10.1109/tit.2004.830763 fatcat:jge7nyydxngdhfbb7fow737m4m

Molecular insights on ABL kinase activation using tree-based machine learning models and molecular docking

Philipe Oliveira Fernandes, Diego Magno Martins, Aline de Souza Bozzi, João Paulo A Martins, Adolfo Henrique de Moraes, Vinícius Gonçalves Maltarollo
2021 Molecular diversity  
We used molecular docking simulations combined with tree-based machine learning models-decision tree, AdaBoost, and random forest to understand the c-Abl activators' structural features required for binding  ...  In these models, the goal is to split the dataset into binary groups with the highest possible homogeneity. In the beginning, the chosen feature allows the highest gain on homogeneity.  ...  In the region most exposed to the solvent, the compounds access various interaction sites such as hydrogen bond acceptors and donors and Van der Waals interactions, depending on their substituting groups  ... 
doi:10.1007/s11030-021-10261-z pmid:34191245 pmcid:PMC8241884 fatcat:ja7igobhizhjfjgqshkgsnkzaa

Multiattribute hashing using Gray codes

Christos Faloutsos
1986 Proceedings of the 1986 ACM SIGMOD international conference on Management of data - SIGMOD '86  
the binary codes We also discuss how Gray codes could be apphed to some retrieval methods designed for range queries, such as the grid file [Nlevergelt84a] and the approach based on the socalled z -ordermg  ...  , replacmg them with sequential ones We develop a mathematical model, derive formulas glvmg the average performance of both methods and show that the proposed method achieves 0% -50% relative savings over  ...  lO" of the previous example The buckets that qualify m the Gray code method are buckets #3, #4, #ll and #12, which require only 2 random accesses, mstead of the 4 random accesses that the binary method  ... 
doi:10.1145/16894.16877 dblp:conf/sigmod/Faloutsos86 fatcat:6fxs5wyknjgn3guvgqsziicvmm

Two simple full-text indexes based on the suffix array [article]

Szymon Grabowski, Marcin Raniszewski
2016 arXiv   pre-print
The other, called FBCSA, is a compact data structure, similar to Mäkinen's compact suffix array, but working on fixed sized blocks.  ...  One, called SA-hash, augments the suffix array with a hash table to speed up pattern searches due to significantly narrowed search interval before the binary search phase.  ...  This structure still allows for binary search, only the accesses to SA cells require local decompression.  ... 
arXiv:1405.5919v2 fatcat:wrcgvcsxmjcerldwo2czbivj2m

Extended Compact Web Graph Representations [chapter]

Francisco Claude, Gonzalo Navarro
2010 Lecture Notes in Computer Science  
Many relevant Web mining tasks translate into classical algorithms on the Web graph. Compact Web graph representations allow running these tasks on larger graphs within main memory.  ...  We present a compact Web graph representation that, in addition, supports reverse navigation (to the nodes pointing to the given one).  ...  On one hand, we achieve the most compact functional Web graph representation reported up to date.  ... 
doi:10.1007/978-3-642-12476-1_5 fatcat:egxfczi44vfy3hrb5t7mtwp6yq

EBPA: An efficient data structure for frequent closed itemset mining

C. Vajiramedhin, J. Werapun
2013 Applied Mathematical Sciences  
Therefore, this paper presents the improved collaboration data structure, called the EBPA (Efficient Bitmap-Prefix-tree Array), with the efficient (parent-child) access in O(1) by using a (temporary) pointer  ...  That collaboration can save space over that of the original prefix tree, which requires extra space for (m-1) parent-child pointers and its corresponding hashing table (in each tree-node).  ...  " based on the efficient (parent-child) access of the prefix-tree array in O(1) and the EBPA-CLOSED algorithm to improve both time and space for the FCIM mining.  ... 
doi:10.12988/ams.2013.13135 fatcat:qrmnxy62ifdhdfi6tpfckat2sa

Lossless And Gradual Coding Of Hyperspectral Images By Lifting Scheme

Asma Chourou, A. Benazza-Benyahia
2007 Zenodo  
The two first methods impose a given coding order whereas the remaining ones are adapted to the content of the components.  ...  ∑ B b=1 (u cb ) 2 ( f (b) − φ c ) 2 ∑ B b=1 (u cb ) 2 . (4) The objective function J of the CAA combines two terms.  ... 
doi:10.5281/zenodo.40332 fatcat:p6yvzeb535amncbuz2uosbaf6y
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