Research Interest

I/O efficient algorithms, data and index structures, computational geometry

Past Projects

• PhD Project: Bulk-loading and bulk updates on multiversion B-trees
• Project: XXL Java Library Project (eXtensible and fleXible Library)
• Project: Distributed Algorithms for Spatial Query Processing and Loading Multidimensional Indexes

Data sets and source code

• Bulk-loading and bulk updates algortihms for MVBT (Multiversion B-Tree, MVBT+), R-tree query adaptive bulk-loading (GOPT/OPT dynamic programming based partitioning) and R-tree Histograms: XXL Java Library Project (eXtensible and fleXible Library) Git repository (xxl index structures, MVBT+, xxl r-tree bulk-loading, xxl r-tree bulk-loading example, spatial histograms).
• Spatial Data used in experiments with R-trees and Histograms (Query Model 4, queries follow data distribution) (description). Files contain DoublePointRectangle objects (following format x_low, y_low, ..., x_high, y_high, ...). Rectangles are normalized to unit cube [0,1)^d : data, point queries, range queries (avg. sel. 100), range queries (avg. sel. 1000)
• Divide & conquer algorithm for Z-Order

Publications

• Daniar Achakeev: Efficient bulk-loading methods for temporal and multidimensional index structures; PhD Thesis, Philipps-Universität Marburg, 2014; [pdf]
• Daniar Achakeev, Bernhard Seeger: Efficient Bulk Updates on Multiversion B-trees, PVLDB Vol. 6 No. 14, VLDB 2014; [link]
• Daniar Achakeev, Marc Seidemann, Markus Schmidt, Bernhard Seeger: Sort-based Parallel Loading of R-trees, ACM SIGSPATIAL BigSpatial 2012 Workshop; (Best Paper Award); [link]; talk [slides]
• Daniar Achakeev, Bernhard Seeger: A class of R-tree histograms for spatial databases, ACM SIGSPATIAL GIS 2012; [link];
  Extended Version, Technical Report, Department of Mathematics and Computer Science, University of Marburg, 2012 [pdf]
• Daniar Achakeev, Bernhard Seeger, Peter Widmayer: Sort-based Query-adaptive Loading of R-trees, CIKM 2012; [link];
  Extendend version, Technical report, Department of Mathematics and Computer Science, University of Marburg, 2012 [pdf]
• Daniar Achakeyev: Effiziente Indexstrukturen fÜr zeitabhängige RDF Daten; Diplomarbeit, Fachbereich Mathematik und Informatik, Philipps-Universität Marburg, Februar 2009 [pdf]

External Reviewer

SSTD 2009, ACM GIS 2010, SSTD 2011, BTW 2011, SSTD 2013