Filters








1,916 Hits in 5.9 sec

An experimental analysis of iterated spatial joins in main memory

Benjamin Sowell, Marcos Vaz Salles, Tuan Cao, Alan Demers, Johannes Gehrke
2013 Proceedings of the VLDB Endowment  
Many modern applications rely on high-performance processing of spatial data.  ...  In this paper, we perform an extensive evaluation of repeated spatial join algorithms for distance (range) queries in main memory.  ...  funded by the Research Council of Norway, and by gifts from NEC and Google.  ... 
doi:10.14778/2556549.2556570 fatcat:4vcv7mofxrfyrl65qqgtbuduqm

Join processing in relational databases

Priti Mishra, Margaret H. Eich
1992 ACM Computing Surveys  
Factors that affect the performance of the wave-based join operation on kd-tree indexed relations are as follows: (1) Wave size. (2) Join range, which may be determined from the point of view of either  ...  KITSUREGAWA, M , HARADA, L , AND TAKAGI, M 1989b. Join strategies on Kd-tree indexed re- lations.  ... 
doi:10.1145/128762.128764 fatcat:u2fdsytzmbauxnyqkwozxxk3bi

SparkNN: A Distributed In-Memory Data Partitioning for KNN Queries on Big Spatial Data

Zaher Al Aghbari, Tasneem Ismail, Ibrahim Kamel
2020 Data Science Journal  
The results show SparkNN significantly outperforms the state-of-the-art Spark system when evaluated on the same set of queries.  ...  SparkNN is implemented on top of Apache Spark and consists of three layers to facilitate efficient spatial queries.  ...  It implemented various query processing algorithms like range, kNN, and join.  ... 
doi:10.5334/dsj-2020-035 fatcat:3z7ftetwarhe5jn5lqqezi6t6e

Scalable Clustering Algorithm for N-Body Simulations in a Shared-Nothing Cluster [chapter]

YongChul Kwon, Dylan Nunley, Jeffrey P. Gardner, Magdalena Balazinska, Bill Howe, Sarah Loebman
2010 Lecture Notes in Computer Science  
We evaluate its performance and scalability using a real dataset comprised of 906 million points, and show that in an 8-node cluster, our algorithm can process even a highly skewed dataset 17 times faster  ...  We implement dFoF on the shared-nothing parallel data processing framework Dryad [15] , and evaluate it on real data from the astronomy simulation domain.  ...  Simulations "Cosmo25" and "Cosmo50" were graciously supplied by Tom Quinn and Fabio Governato of the University of Washington Department of Astronomy.  ... 
doi:10.1007/978-3-642-13818-8_11 fatcat:2akf3lx5qffupirf4hkul7ol7a

Tree-based Indexing for DHT-based P2P Systems

Yi YiMar, Aung Htein Maw, Khine Moe Nwe
2013 International Journal of Computer Applications  
Therefore the performance of kd-tree is studied and show that how it can affect the proposed index over P2P network.  ...  In this paper, PlanetSim simulator is used to implement the proposed index and evaluate the performance of the index by using various metrics.  ...  Evaluation of Kd-tree The proposed index is built based on the kd-tree. Therefore the performance of kd-tree is firstly evaluated to show how it can affect on the proposed indexing scheme.  ... 
doi:10.5120/10133-4923 fatcat:u6kkjl5vrzgtvena4ung6qveou

R*-Grove: Balanced Spatial Partitioning for Large-Scale Datasets

Tin Vu, Ahmed Eldawy
2020 Frontiers in Big Data  
Previous works on big spatial partitioning are to reuse existing index search trees as-is, e.g., the R-tree family, STR, Kd-tree, and Quad-tree, by building a temporary tree for a sample of the input and  ...  Regardless of their architecture, one of the fundamental requirements of all these systems is to spatially partition the data efficiently across machines.  ...  ., 2013) builds Kd-tree-like and Quad-tree-like indexes on top of HBase by applying the Z-curve on the input data and customizing the region split method in HBase to respect the structure of both indexes  ... 
doi:10.3389/fdata.2020.00028 pmid:33693401 pmcid:PMC7931855 fatcat:ki5edhnx2bg5rjwxbuwoa5fmwi

A Survey on Efficient Processing of Similarity Queries over Neural Embeddings [article]

Yifan Wang
2022 arXiv   pre-print
Then we talk about recent approaches on designing the indexes and operators for highly efficient similarity query processing on top of embeddings (or more generally, high dimensional data).  ...  In this survey, we first provide an overview of the "similarity query" and "similarity query processing" problems.  ...  Traditional similarity/distance based indexes like KD-tree work well on low-dimensional data but perform weakly on high-dimensional data due to the curse of dimensionality.  ... 
arXiv:2204.07922v1 fatcat:u5osyghs6vgppnj5gpnrzhae5y

Mobile Location Indexing Based On Synthetic Moving Objects

Thu Thu Zan, Sabai Phyu
2019 International Journal of Electrical and Computer Engineering (IJECE)  
In this paper, a structure, a presorted-nearest index tree algorithm is proposed that allowed maintaining, updating, and range querying mobile objects within the desired period.  ...  The detail experimental results are discussed together with the performance evaluation of KDtree-based index structure. Both approaches are similarly efficient in range searching.  ...  Sabai Phyu, Professor, the University of Computer Studies, Yangon. I would not be able to continue without her supervision and valuable guidance during period of the research study.  ... 
doi:10.11591/ijece.v9i4.pp2556-2563 fatcat:b3cbtmxm4jb6rd7fsoewmheyqy

A 3D Surface Reconstruction Method for Large-Scale Point Cloud Data

Baoyun Guo, Jiawen Wang, Xiaobin Jiang, Cailin Li, Benya Su, Zhiting Cui, Yankun Sun, ChangLei Yang
2020 Mathematical Problems in Engineering  
A method based on the idea of divide and conquer approaches is proposed. Firstly, the kd-tree index was created for the point cloud data.  ...  The proposed method performed surface reconstruction on the point cloud in the multicore parallel computing architecture, in which memory release and reallocation were implemented to reduce the memory  ...  Kd-Tree Index Construction.  ... 
doi:10.1155/2020/8670151 fatcat:q77c225mvvcldosuaka63zi4cy

A Lightweight Multidimensional Index for Complex Queries over DHTs

Yuzhe Tang, Jianliang Xu, Shuigeng Zhou, Wang-Chien Lee, Dingxiong Deng, Yue Wang
2011 IEEE Transactions on Parallel and Distributed Systems  
We also conduct an extensive performance evaluation of m-LIGHT in comparison with several state-of-theart indexing schemes.  ...  We present detailed algorithms for processing complex queries over the m-LIGHT index.  ...  ACKNOWLEDGMENTS The work of Yuezhe Tang  ... 
doi:10.1109/tpds.2011.91 fatcat:hbbbkvf525hldbe3g52rlcpnoy

Hybrid KNN-Join: Parallel Nearest Neighbor Searches Exploiting CPU and GPU Architectural Features [article]

Michael Gowanlock
2020 arXiv   pre-print
Compared to the reference implementations, we find that the hybrid algorithm performs best on larger workloads (dataset size and K).  ...  K Nearest Neighbor (KNN) joins are used in scientific domains for data analysis, and are building blocks of several well-known algorithms. KNN-joins find the KNN of all points in a dataset.  ...  Related Work We present an overview of several categories of related work below. Hybrid Algorithms A significant fraction of research on GPU algorithms and applications compares CPU vs.  ... 
arXiv:1810.04758v2 fatcat:t4t44mwcfzbfdm7uds5uvz45ey

EFANNA : An Extremely Fast Approximate Nearest Neighbor Search Algorithm Based on kNN Graph [article]

Cong Fu, Deng Cai
2016 arXiv   pre-print
The performance of traditional hierarchical structure (tree) based methods decreases as the dimensionality of data grows, while hashing based methods usually lack efficiency in practice.  ...  To the best of our knowledge, EFANNA is the fastest algorithm so far both on approximate nearest neighbor graph construction and approximate nearest neighbor search.  ...  Any opinions, findings, and conclusions expressed here are those of the authors and do not necessarily reflect the views of the funding agencies.  ... 
arXiv:1609.07228v3 fatcat:2jwivsuv3fd5pc4watrvesjzda

Partition based spatial-merge join

Jignesh M. Patel, David J. DeWitt
1996 Proceedings of the 1996 ACM SIGMOD international conference on Management of data - SIGMOD '96  
This paper also presents a performance study comparing the the traditional indexed nested loops join algorithm, a spatial join algorithm based on joining spatial indices, and the PBSM algorithm.  ...  The study also examines the effect of clustering the join inputs on the performance of these join algorithms.  ...  Grid files [NHS84] and kd-trees [Ben75, Ben79] have also been employed for evaluating multi-attribute joins in the relational domain [KHT89, HNKT90, BHF93] .  ... 
doi:10.1145/233269.233338 dblp:conf/sigmod/PatelD96 fatcat:hijmh6y43vfahd2yddxklctntu

Partition based spatial-merge join

Jignesh M. Patel, David J. DeWitt
1996 SIGMOD record  
This paper also presents a performance study comparing the the traditional indexed nested loops join algorithm, a spatial join algorithm based on joining spatial indices, and the PBSM algorithm.  ...  The study also examines the effect of clustering the join inputs on the performance of these join algorithms.  ...  Grid files [NHS84] and kd-trees [Ben75, Ben79] have also been employed for evaluating multi-attribute joins in the relational domain [KHT89, HNKT90, BHF93] .  ... 
doi:10.1145/235968.233338 fatcat:lzoeyf5ebrakfoloj6us442pyu

MR-DBIFOA: a parallel Density-based Clustering Algorithm by Using Improve Fruit Fly Optimization

Wei Liu Wei Liu, Jiaxin Wang Wei Liu, Xiaopan Su Jiaxin Wang, Yimin Mao Xiaopan Su
2022 Diànnǎo xuékān  
Firstly, based on KD-Tree, a division strategy (KDG) is proposed to divide the cell of grid adaptively.  ...  Finally, based on QR-Tree and MapReduce, a cluster merging algorithm (MR-QRMEC) is proposed to get the result of clustering algorithm more quickly, which improve the core clusters merging efficiency of  ...  Acknowledgement This study was supposed by the National Natural Science Foundation of China (41562019, 41530640), the National Key Research Development Projects of China (2018YFC1504705), and Jiangxi Provincial  ... 
doi:10.53106/199115992022023301010 fatcat:gzehehxvwngipg3vhdeeiuuk4u
« Previous Showing results 1 — 15 out of 1,916 results