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The hB^Pi -tree: a multi-attribute index supporting concurrency, recovery and node consolidation
No full textWe propose a new multi-attribute index. Our approach combines the hB-tree, a multi-attribute index, and the Π-tree, an abstract index which offers efficient concurrency and recovery methods. We call the resulting method the hBΠ-tree. We describe several versions of the hBΠ-tree, each using a different node-splitting and index-term-posting algorithm. We also describe a new node deletion algorithm. We have implemented all the versions of the hBΠ-tree. Our performance results show that even the version that offers no performance guarantees, actually performs very well in terms of storage utilization, index size (fan-out), exact-match and range searching, under various data types and distributions. We have also shown that our index is fairly insensitive to increases in dimension. Thus, it is suitable for indexing high-dimensional applications. This property and the fact that all our versions of the hBΠ-tree can use the Π-tree concurrency and recovery algorithms make the hBΠ-tree a promising candidate for inclusion in a general-purpose DBMS.6112
Job creation and temporary emigration: The Albanian experience
No full textThis paper focuses on job flows and unemployment in Albania during the transition from a closed, communist system to an open, free-market economy, and examines the role of emigration in the restructuring of the country. Our theoretical model indicates that in Albania, temporary emigration may have a significant positive effect on hiring in the private sector, reducing unemployment. Using sectoral data on employment, we illustrate the importance of emigration as an alternative for the Albanian labour force, and we measure the extent to which job 'destruction' in some sectors of the economy has been compensated for by job 'creation' in others. On these grounds, we compare the progress of Albania with other former socialist countries in Europe.4247149
Το διεθνές και ευρωπαϊκό καθεστώς προστασίας των μειονοτήτων και η ελληνική έννομη τάξη
No full textΤα γλωσσικά δικαιώματα των μειονοτήτων μόλις στα μέσα της δεκαετίας του 1990 άρχισαν να προστατεύονται από διατάξεις διεθνούς δικαίου. Στην Ελλάδα το καθεστώς παραμένει ατελές, με μόνη αναφορά τη Συνθήκη της Λοζάνης αναφορικά με τα δικαιώματα στη μητρική γλώσσα της μειονότητας της Θράκης
The hBP-tree - A Modified hB-tree Supporting Concurrency, Recoveryand Node Consolidation
No full textWe describe a new access method, the hB\Pi-tree, an adaptation of the hB-tree index to the constraintsof the Pi-tree. The Pi-trees, a generalization of the B link-trees, provide high concurrency with recovery,because they break down structure modification into a series of short atomic actions. In addition, the IItrees include a node consolidation algorithm. The hB-tree is, a multi-attribute index which is highly insensitive to dimensionality, but which has no node consolidation algorithm and has a flaw in its split/post algorithm in certain special cases. The hB\Pi-tree corrects the splitting/posting algorithm and adapts the concurrency, recovery and node consolidation of the Pi-tree to the hB-tree. The combination makes the hB\Pi-tree suitable for inclusion in a general purpose database management system.supporting multi-attribute and spatial queries.551561VLDB'95, Proceedings of 21th International Conference on Very LargeData Bases, September 11-15, 1995, Zurich, Switzerlan
Using the Holy Brick Tree for Spatial Data in General Purpose DBMSs
No full text1633439Special Issue on Geographical Information System