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STORAGE OVERHEAD OF O-TREES, B-TREES AND PREFIX B-TREES: A COMPARATIVE ANALYSIS

RATKO ORLANDIC, HOSAM M. MAHMOUD
1996 International Journal of Foundations of Computer Science  
In this paper we derive the expected storage overhead of O-Trees under the standard Bernoulli model of randomness, compare the results with the expected overhead of Btrees and Pre x B-trees under the same  ...  The O-tree is an indexing mechanism closely related to B-trees and Pre x B-trees.  ...  From the experimental evidence in 3], we concluded that the average storage utilization of index blocks in a Pre x B-tree is closely approximated by ln 2.  ... 
doi:10.1142/s0129054196000166 fatcat:ouzd5klarndopjabjmsbbvcbyq

Bounded disorder: The effect of the index

Ricardo A. Baeza-Yates
1996 Theoretical Computer Science  
In this paper we complete the analysis done by Ramakrishna and Mukhopadhyay for a data node in the bounded disorder (BD) file organization of Litwin and I.omet. by introducing the B-tree index into the  ...  Our main contribution is a detailed analysis of search and insertion costs, and its comparison with P-trees.  ...  Acknowledgements We wish to thank all the encouragement and pointers received from Per-Ake Larson and the helpful comments of the referees and Vinay Deshpande, to whom I dedicate this paper.  ... 
doi:10.1016/s0304-3975(96)00061-8 fatcat:zgtczsooznc4dfjofkdbfq2ktm

A Decentralized Storage Scheme for Multi-Dimensional Range Queries over Sensor Networks

Lei Xie, Lijun Chen, Daoxu Chen, Li Xie
2009 2009 15th International Conference on Parallel and Distributed Systems  
This paper presents the design of a decentralized storage scheme to support multi-dimensional range queries over sensor networks.  ...  We build a distributed k-d tree based index structure over sensor network, so as to efficiently map high dimensional event data to a two-dimensional space of sensors while preserving the proximity of events  ...  B.  ... 
doi:10.1109/icpads.2009.24 dblp:conf/icpads/Xie0CX09 fatcat:a52dglvlr5ehjiub4x6svqmcdi

The A-tree: An Index Structure for High-Dimensional Spaces Using Relative Approximation

Yasushi Sakurai, Masatoshi Yoshikawa, Shunsuke Uemura, Haruhiko Kojima
2000 Very Large Data Bases Conference  
We propose a novel index structure, A-tree (Approximation tree), for similarity search of high-dimensional data.  ...  Therefore, by fetching a node of an A-tree, we can obtain the information of exact position of a parent MBR and approximate position of its children.  ...  Storage Cost Figure 14 compares the storage cost of the A-tree to that of the SR-tree under the same conditions as used in Figure 5 (b).  ... 
dblp:conf/vldb/SakuraiYUK00 fatcat:ourzm5kbvva5roxhekbceyivu4

Height-balanced trees of order (β, γ, δ)

Shou-Hsuan S. Huang
1985 ACM Transactions on Database Systems  
Properties of H-trees are given in Section 3. It is shown that the height of H-trees decreases as y increases, and the storage utilization increases significantly as 6 increases.  ...  We study restricted classes of B-trees, called H(p, y, 8) trees.  ...  In particular, one of the referees pointed out that there are 0 (log K) update algorithms for stratified subclasses [ 151 of H-trees and r-dense m-way trees. The author would also like to thank Prof.  ... 
doi:10.1145/3857.3858 fatcat:cwftqtnmqvdsnms77rmlhrhbmq

B+ trees and indexed sequential files

D. S. Batory
1981 Proceedings of the 1981 ACM SIGMOD international conference on Management of data - SIGMOD '81  
An analytic method for comparing the performance of B+.trees and indexed sequential files is proposed.  ...  Preliminary results indicate that indexed sequential files may be more efficient than B+ trees in certain applications.  ...  Edelberg for suggesting the topic of this paper. I also thank Dr. K.C. Sevcik for his helpful insights and suggestions.  ... 
doi:10.1145/582318.582323 dblp:conf/sigmod/Batory81 fatcat:fgi6gouvuvgpzlkunsnmpfjt4m

B+ trees and indexed sequential files

D. S. Batory
1981 Proceedings of the 1981 ACM SIGMOD international conference on Management of data - SIGMOD '81  
An analytic method for comparing the performance of B+.trees and indexed sequential files is proposed.  ...  Preliminary results indicate that indexed sequential files may be more efficient than B+ trees in certain applications.  ...  Edelberg for suggesting the topic of this paper. I also thank Dr. K.C. Sevcik for his helpful insights and suggestions.  ... 
doi:10.1145/582319.582323 fatcat:g56eyiq6wjbkloemmbafp4fcbi

The K-D-B-tree

John T. Robinson
1981 Proceedings of the 1981 ACM SIGMOD international conference on Management of data - SIGMOD '81  
Preliminary experimental results support this: as "random" records are inserted, storage utilization seems to stay around 60% for cyclic 2-D-B-trees and 3-D-B-trees (see Section 4 for the definition of  ...  be approximated in K-D-B-trees.  ...  This definition ignores storage utilization considerations (to get query efficiency as compared to queries on the "perfect" K-D-B-tree, multiply the above by storage utilization).  ... 
doi:10.1145/582318.582321 dblp:conf/sigmod/Robinson81 fatcat:mqjkkttxozesdodrodqgrwdqki

Transaction time indexing with version compression

David Lomet, Mingsheng Hong, Rimma Nehme, Rui Zhang
2008 Proceedings of the VLDB Endowment  
A main challenge was integrating TSB-tree functionality while preserving original B+tree functionality, including concurrency control and recovery.  ...  There is a tradeoff between query performance and storage space. We discuss optimizing performance regarding this tradeoff throughout the paper.  ...  Time Split B+tree The first focus of this paper is the integrated indexing of historical and current records, by both key and by time, into Immortal DB using the Time Split B+tree, or TSB-tree [28] .  ... 
doi:10.14778/1453856.1453951 fatcat:hztznavbffbhfegm7wl7x3ienu

Quality and productivity in comminution of small-diameter tree bundles

Yrjö Nuutinen, Aaron Petty, Dan Bergström, Matleena Rytkönen, Fulvio Di Fulvio, Ismo Tiihonen, Ari Lauren, Bo Dahlin
2016 International Journal of Forest Engineering  
Storage: Roadside storage (2 months), terminal storage (6 months); Approximately 1,000 m 3 s. of cross layered bundles 5 m in height were placed at the terminal study site.  ...  FX15a small tree bundler in May, 2013. • Approximate dimensions of bundles: 2.6 m x 60 -70 cm ( 0.6 m 3 s.). • Size of whole trees in bundles: 15 -35 dm 3 (5 -13 cm (dbh)) with average stem sizes of 25  ... 
doi:10.1080/14942119.2016.1223926 fatcat:ign37mtgjjdqrmodpi6d5qwfiy

On Optimal Balance in B-Trees: What Does It Cost to Stay in Perfect Shape?

Rolf Fagerberg, David Hammer, Ulrich Meyer, Michael Wagner
2019 International Symposium on Algorithms and Computation  
Finally, we prove that this balancing scheme gives B-trees with very good storage utilization. ACM Subject Classification Theory of computation → Data structures design and analysis  ...  We investigate exactly how close to log B (n) the height of dynamic B-trees can be maintained as a function of the rebalancing cost.  ...  Standard B-trees have a worst-case storage utilization of approximately 1/2 and a logarithmic rebalancing cost.  ... 
doi:10.4230/lipics.isaac.2019.35 dblp:conf/isaac/FagerbergH019 fatcat:wtgl26z4njd4zphlgses2xciue

Studies of Rest Period. III. Respiratory Changes in Leaf Primordia of Maple Buds During Chilling

B. M. Pollock
1960 Plant Physiology  
However, in both cases the efficiency of utilization declines with increased duration of storage.  ...  These trees were grown in the garden under normal environmental conditions, and pruned several times to produce a number of approximately uniform terminal buds on each tree.  ... 
doi:10.1104/pp.35.6.975 pmid:16655451 pmcid:PMC406068 fatcat:pqllc4gvjzh5jhynf6ri6wg7zy

Spatial Distributions of Carbon Storage and Uptake of Urban Forests in Seoul, South Korea

Do-Hyung Lee, Sung-Ho Kil, Hyun-Kil Jo, Byoungkoo Choi
2019 Sensors and materials  
Results indicate that the total carbon storage and carbon uptake of Seoul are approximately 1459024 t and 147388 t/yr, respectively; the corresponding per unit area values are approximately 24.03 t/ha  ...  Hence, herein, carbon storage and carbon uptake per capita are quantified and mapped for all administrative districts of the Seoul Metropolitan City through (1) the analysis of tree cover via on-site tree  ...  Acknowledgments This study was carried out with the support of the 'R&D Program for Forest Science Technology (Project No. 2017043B10-1919-BB01)' provided by the Korea Forest Service (Korea Forestry Promotion  ... 
doi:10.18494/sam.2019.2556 fatcat:cipoduopo5h3hjd2l3nysk74yy

Modern B-Tree Techniques

Goetz Graefe
2010 Foundations and Trends in Databases  
For all of those operations, including incremental and online variants of the utilities, B-trees also enable efficient concurrency control and recovery.  ...  Perhaps the "B" in their name "B-trees" should stand for their balanced performance across queries, updates, and utilities.  ... 
doi:10.1561/1900000028 fatcat:uisqivwiqre4jg2yug4vf6u3ve

4.-8. März 2019

Nikolaus Glombiewski, Bernhard Seeger, Goetz Graefe
2019 Datenbanksysteme für Business, Technologie und Web  
After creation of a new b-tree, the ordinary course of database updates and index maintenance causes waves of node splits.  ...  Waves of misery occur in databases and in key-value stores, in primary and in secondary b-tree indexes, after load operations, and after b-tree reorganization or rebuild.  ...  Then, the loaded b-tree guarantees a storage utilization of ln 2. Unfortunately, there is no steady-state solution with a higher storage utilization for the loaded b-tree.  ... 
doi:10.18420/btw2019-06 dblp:conf/btw/GlombiewskiSG19 fatcat:vcpqulyrxrcbpjjxsmk3ug2uye
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