1. Smart Home Technologies Data Management and Databases

2. Databases for Smart Homes Requirements Database Types Database Technologies Smart Home Databases Data Mining

3. Data Storage Requirements Sensor data Temperature (15 @ 8 Kbps) Humidity (15 @ 8 Kbps) Gas (15 @ 8 Kbps) Light (15 @ 8 Kbps) Motion (15 @ 8 Kbps) Pressure (100 @ 8 Kbps) Microphone (15 @ 500 Kbps) Camera (15 @ 10 Mbps)

4. Data Storage Requirements User data Multimedia Phone messages/conversations (500 Kbps – 10 Mbps) Music (500 Kbps) TV/Radio broadcasts (500 Kbps – 10 Mbps) Home movies (10 Mbps) Images Computer Programs Data files Operating systems

5. Data Storage Issues Issues Query frequency and type Sampling/recording rates 205 sensors (158,900 Kbps) Multimedia recordings Simultaneous playback Analysis, prediction, decision-making queries Transaction granularity Historical data, decay Security and privacy Centralized vs. distributed

6. What Data to Store Type of Data Raw data Pre-processed Compressed Frequency of Data Storage for Sensor Data Tradeoff between precision and quantity

7. Sensor Data Example 9/8/2002 2:0:1 AM~A5 (Coffee Maker) ON 9/8/2002 1:6:59 AM~A9 (A/C) ON 9/8/2002 3:58:52 AM~A0 (Stereo) ON 9/8/2002 5:57:0 AM~A2 (Kitchen Light) ON 9/8/2002 3:1:42 AM~A5 (Coffee Maker) OFF 9/8/2002 7:8:3 AM~A3 (Stove) ON 9/8/2002 12:54:52 PM~A10 (Bathroom Light) ON 9/8/2002 4:58:5 AM~A0 (Stereo) OFF 9/8/2002 8:1:20 AM~A3 (Stove) OFF 9/8/2002 9:6:10 AM~A8 (Computer) ON 9/8/2002 10:8:19 AM~A4 (Bathtub Heater) ON 9/8/2002 11:9:4 AM~A0 (Stereo) ON 9/8/2002 9:4:5 AM~A8 (Computer) OFF 9/8/2002 10:9:4 AM~A4 (Bathtub Heater) OFF 9/8/2002 2:2:5 PM~A10 (Bathroom Light) OFF 9/8/2002 2:52:37 PM~A0 (Stereo) OFF 9/8/2002 4:2:0 PM~A9 (A/C) OFF

8. Media Viewing Example

9. Multimedia Example Digital Silhouettes (Predictive Networks) Predicting web surfing behavior ($$$) Microsoft (2002) track TV viewing preferences 140 data items for each user Demographics (50) Subcategories within gender, age, income, education, occupation, and race 90 Content preferences golf, music, yoga

10. Database Types / Data Models Relational OO Hybrid (Object-Relational) Temporal Deductive Others Spatial, …

11. Example Data Representations Relational We all know…flat tables of atomic attributes with foreign key relationships OO Complex data reps multivalued, composite Temporal Relational model: add valid start, end dates to each table (versions of info and when valid) Includes time, events, durations…

12. Operations DDL/DML (data def/manip languages) SQL OQL Update operations Built-in insert, delete, update Stored procedures for triggers, active (ECA) rules

13. Example Operations for Temporal Databases INCLUDES Rows valid in a certain time period BEFORE/AFTER a time condition Set operations Union, intersection of 2 time periods

14. Active DB Event-Condition-Action rules Allow for decisions to be made in the database instead of a separate application Relational Implemented as triggers Challenges Rule consistency (2+ rules do not contradict) Guaranteed termination Trigger loops (T1 T2)

15. Smart Home Active DB Example Java, Postgres, Jess rules Event classification (local&composite) Data Manipulation Events TV show being viewed (channel, time, genre…) Temporal Events (instance,recurring) Set temp to 70 degrees at 7:00am workdays Exception Events Power failure Behavioral Events Time children home from school; dinner time

16. Active DB Example (TCU) TitleEventConditionAction TV View Menu TV turned onMolly is holding remote Display shows matching Molly’s preferences Entry Lighting Inhabitant enters house Light level <threshold Adjust lighting to predetermined level Aroma- therapy Every Friday night when Hanna sits on sofa AlwaysRelease aroma Night IdleJohn on sofa idle > 15 minutes, TV&lights are on No other inhabitant in room Turn off all devices in the room

17. Distributed vs. Centralized Centralized database can produce a bottleneck Large volume of data input Large database Large volume of queries In distributed databases, data consistency, replication, and retrieval can be more problematic Consistency of schemas Retrieval in case the data location is not known Communication overhead to ensure database consistency

18. SmartHome Database Architecture Centralized vs. distributed? Answer: Both Central storage of high demand, persistent data Distributed storage of low demand, dynamic data Distributed queries Push processing toward sensors Adaptive, hierarchical organization End-effector autonomy (“smart sensor”)

19. Database Systems Commercial DB2 Empress Informix Oracle MS Access MS SQL Sybase Free Berkeley DB PostgreSQL MySQL

20. UTA MavHome DB Active Reactive & proactive (e.g., to predict) Distributed Information collection agents Rules Local Agent: what data they need to collect Distributed: coordinate overall monitoring of collected information Continuous monitoring of events Extension of SNOOP

21. Microsoft Easy Living DB (2002) Relational Fast & robust, but awkward for some data World Model DB Describes: Computing devices People and their personal preferences/settings Services Rooms and doorways Serves as Abstraction Layer between sensors and application that use data from sensors e.g. new sensors  no change to applications

22. Stanford Interactive Workspace Uses LORELORE A semi-structured XML DB system Still available, but work stopped in 2000 Data stored is catalog of (index to) documents, images, 3-D models, application- specific domain models

23. Sensor Database Systems COUGAR project www.cs.cornell.edu/database/cougar Query processing over ad-hoc sensor networks Small database component (QueryProxy) at each sensor Sensor clusters provide local aggregations (e.g., min, max, mean) Assumes centralized index of all data sources

24. Siemens Netabase “The network is the database.” Navas and Wynblatt, ACM SIGMOD 2001 Sensor networks Large number of data sources (105) Volatile data and data organization “Thin” data servers on scaled-down hardware Netabase approach Query decomposition Characteristic routing (ala IP routing) Local joins Query evaluation

25. Siemens Netabase www.netabasesoftware.com

26. Data Warehouses Repositories for data mining activities Aggregates/summaries of data help efficiency Optimized for decision-support, not transaction processing Definition (Elmasri, page 900) A subject-oriented, integrated, non-volatile, time- variant collection of data in support of management’s decisions” Replace “management”, with “smart home agents”

27. Warehouse Properties Very large: 100gigabytes to many terabytes Tends to include historical data Workload: mostly complex queries that access lots of data, and do many scans, joins, aggregations. Tend to look for "the big picture". Updates pumped to warehouse in batches (overnight) Data may be heavily summarized and/or consolidated in advance (must be done in batches too, must finish overnight). Research work has been done (e.g. "materialized views") -- a small piece of the problem. 02.15.04 from http://redbook.cs.berkeley.edu/lec28.html

28. Data Warehouses Data Cleaning Data Migration: simple transformation rules (replace "gender" with "sex") Data Scrubbing: use domain-specific knowledge (e.g. zip codes) to modify data. Try parsing and fuzzy matching from multiple sources. Data Auditing: discover rules and relationships (or signal violations thereof). Not unlike data mining. Data Loading can take a very long time! (Sorting, indexing, summarization, integrity constraint checking, etc.) Parallelism a must. Full load: like one big xact – change from old data to new is atomic. Incremental loading ("refresh") makes sense for big warehouses, but transaction model is more complex – have to break the load into lots of transactions, and commit them periodically to avoid locking everything. Need to be careful to keep metadata & indices consistent along the way. 02.15.04 from http://redbook.cs.berkeley.edu/lec28.html

29. Data Warehouses 02.15.04 from http://redbook.cs.berkeley.edu/lec28.html

30. Data Mining Definition Discovery of new information in terms of patterns or rules from vast amounts of data Extracts patterns that can’t readily be found by asking the right questions (queries) TOO MUCH DATA FOR HUMANS Emerged from Artificial Intelligence:Machine learning, Neural nets, Genetic Algorithms Statistics Operations Research

31. Data Mining Steps Data selection -- pick the data needed Data cleansing Fix bad data (e.g., spelling, zip codes) Hard to deal with missing, erroneous, conflicting, redundant data Enrichment Add data (e.g., age, gender, income) Data transformation Aggregate (e.g., zip codes  regions) Data mining Reporting on discovered Knowledge

32. Types of Results Association rules Buy diapers  buy lots of beer Sequential patterns Buy house  buy furniture within months Classification trees Types of buyers (upscale,bargain-conscience, …) Why do it? Make more money Science & medicine

33. Data Mining Goals Find patterns to predict future events Find major groupings Groupings of buyers, stars, diseases … Find which group something belongs to creditworthiness

34. Data Mining Results Association rules Classification hierarchies Clustering Sequential patterns Patterns within time series Type of result, inputs & algorithms vary Often interested in some combination of these types of Knowledge

35. Clustering Unsupervised learning techniques Training samples are unclassified Vs. supervised learning (classification) Drug categories for depression Categories of TV viewers Categories of buyers (likely, unlikely) Categories of households? Single male, mother/children, conventional (M/D/kids), DINKs.

36. Sequential Patterns Detecting associations among events with certain temporal relationships Example: Cardiac bypass for blocked arteries AND within 18 months, high blood urea THEN kidney failure likely in next 18 months Particularly important in smart homes

37. Sequential Pattern Discovery Sequence of itemsets Grocery store purchases by 1 person (3 itemsets) {soy milk, bread, chocolate}, {bananas, chocolate}, {lettuce, tomato, chocolate} 2 Subsequences {soy milk, bread, chocolate}, {bananas, chocolate}, {bananas, chocolate}, {lettuce, tomato, chocolate}

38. Sequential Pattern Discovery The support for a sequence S is the % of the given set U of sequences of which S is a subsequence. That is: how many times does S show up? Find all subsequences from the given sequence sets that have a user-defined minimum support. The sequence S1, S2, … Sn, is a predictor of “fact” that a customer that buys itemset S1 is likely to buy itemset S2, then S3, … Prediction support based on frequency of this sequence in the past Many research issues to create good algos

39. Patterns Within Time Series Finding 2 patterns that occur over time 2003 stock prices of Choice Homes and Home Depot 2 products show same sales pattern in summer but different one in winter Solar magnetic wind patterns may predict earth atmospheric changes

40. Time Series Pattern Discovery Time series are sequences of events Event could be a transaction (closing daily stock price) Look at sequences over n days, or Longest period in which change is no greater than 1% Comparing Must define similarity measures

41. Other Approaches in Data Mining Neural nets Infer a function from a set of examples Non-parametric curve-fitting Interpolates to solve new problems Supervised & unsupervised algorithms Capabilities classification time-series prediction Disadvantages can’t see what it learned (not declarative)

42. Other Approaches in Data Mining Genetic algorithms Set up Representation (strings over an alphabet) Evaluation (fitness) function Parameters: # of generations, cross-over rate, mutation rate, etc. Randomized (probabilistic operators), parallel search over search space Used for problem solving and clustering