FYTG 5101 Presentation Data Management For Spatio-temporal Data Of PM 2.5 Indices Through Mobile Sensing Type of This Project: Survey Yun Wen

Outlines Motivation ST Concepts and Models Storage Structure and Indexing

Reliable?

Project: Home Air Quality Sensor Network CO, O 2, PM2.5 Smoke, Temp Humidity +Electricity Consumption

Spatiotemporal Data

SpatioTemporal DataBase Management System Temporal DBMS: existance time, valid-time, transaction-time Spatial DBMS: GIS, environmental information system, trajectory and multimedia

ER Temporal

ER Spatial

ER SpatioTemporal

Storage Structure and Indexing 1D database indexing structures are not appropriate Quad trees K-D-B trees R-tree …..

Quad tree

Type of Data: region quadtree point quadtree Lines/curves quadtree Node Information: Four pointers (NW,NE,SW,SE) Point: key(x,y);value

Quad tree Do not take paging of secondary memory into account Temporal: Linear Quadtree Improved: Overlapping Linear Quadtree

K-D-B tree

Region pages (region,child) + point pages(point,location) Same path length Disjoint page Union of all region in the child is region

K-D-B tree Designed for paged memory, but are useful only for point data

B+ tree

R tree A B+ tree

R tree

Balanced-search tree Organize data in page Overlapped region n entries M maximum Variants: Hilbert R-tree X-tree R* tree, R+ tree

Conclusion All trees are important Trade-off