1 / 12

Research Overview

Research Overview. Kyriakos Mouratidis Assistant Professor School of Information Systems Singapore Management University http://www.mysmu.edu/faculty/kyriakos/. Spatial Queries. - Indexing spatial data and query processing E.g., “find the 10 closest restaurants to my location”

chaka
Download Presentation

Research Overview

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Research Overview Kyriakos Mouratidis Assistant Professor School of Information Systems Singapore Management University http://www.mysmu.edu/faculty/kyriakos/

  2. Spatial Queries - Indexing spatial data and query processing E.g., “find the 10 closest restaurants to my location” - K nearest neighbors (if K=2)

  3. Continuous Queries Continuous re-evaluation as data change. Eg: • “monitor who are the 10 SMU students that are closest to my location as I walk around”

  4. Continuous Queries • Cont. NN in Euclidean space: SIGMOD’05 • Cont. NN in road networks: VLDB’06 • Cont. Top-k monitoring: SIGMOD’06 • Eg: "continuously report the 5 most interesting stocks according to my investment criteria” • Cont. Text queries on document streams: TKDE’11

  5. Spatial Optimization Queries • E.g.: At which 10 positions in S’pore should McDonalds open branches so that the average distance between clients and their closest branch is minimized? • E.g.: Given a coverage radius and a maximum capacity of a Mobile Service Provider’s base stations, find a (dynamic) assignment of mobile phone users to a base station so that the average distance between them is minimal.

  6. Spatial Optimization Example • A set of wireless routers serve a set of laptops • each router can serve at most 3 laptops concurrently • the signal strength (ie, the QoS) drops with distance • How can we assign laptops to routers so that we • Serve the maximum possible number of users, AND • Minimize the average distance between laptops-routers? • Assignments by “local” criteria (eg, NN below) would fail! 3-Nearest Neighbor Queries

  7. Spatial Optimization Example • Optimal Assignment: • Aim: quicklycompute the optimalassignment over large datasets [SIGMOD’08, TODS’10]

  8. Location Privacy • How could an untrusted server answer your spatial queries without learning your location? • Example: shortest path query [VLDB’12]

  9. Building block: Hardware-aided PIR • Practical PIR = hardware-aided PIR[Williams & Sion: Usable PIR. NDSS’08] Fetching a disk page: amortized comp. cost O(log2N) i.e., approx. 1 sec for a Gigabyte database

  10. Verification in Outsourced Databases: • Model: Database as a Service • Data Owner uploads DB to untrusted server • Server hosts the DB and answers queries from users • How can users verify that the results to their queries are authentic and complete? • Examples: text queries [VLDB’08], relational/spatial queries [VLDBJ’09], shortest path queries [ICDE’10]…

  11. Other cool stuff • TripAdvisor has hotel information, such as: price, value, location, cleanliness, user rating • Imagine this interface to select top-10 options: Immutable Regions [VLDB’13]

  12. Thank you!

More Related