Development of a Web-based, Multimedia Database for Collection, Organization and Analysis of Biomedical Signals M.S.C.S. Problem Report Defense Lan Guo Advisor: Dr. Stephanie Schuckers Committee: Dr. Wils Cooley Dr. Bojan Cukic Dr. George Trapp Computer Science and Electrical Engineering West Virginia University Morgantown, WV

Background: Biomedical Signal (ECG) with an Event (VF) Normal VF Normal

 Continuous-time monitoring  Analysis of large time-series datasets  Data mining, Oracle  Prediction and prevention Biomedical Signal Analysis Prediction of Sudden Cardiac Death CSEE CEMR Storage and Processing of Signals Collection of Biomedical Signals Example of Biomedical Signals

Objectives  To build a web-based database which provides efficient management on data collected by Biomedical Signal Analysis Laboratory  To provide these signals to students through web- based front-end to facilitate application-oriented class projects  To provide these signals to the public for outreach purposes.  To utilize database structure for analysis of signals -- temporal data mining

Project Outline  Redesign and implement the back-end database to incorporate other biomedical signal besides ECG signal  Recreate a user-friendly web-based interface for data insert and data query  Develop a secure FTP method which shields the HP9000 data server from public access  Develop an Oracle/Java interface to dynamically display signal on-line

Project Overview  Three tiered web-based database application HP9000 DataServer Data Server Oracle8i Oracle 8i Database Database link WebDB Client J D B C Java Applet ServletServlet Web Server Windows NT

Features of Back-end  Includes several Large Object (LOB) types, BFILE, which point to biomedical signal file and associated files  Provides relevant information regarding the biomedical signals and corresponding signal processing data  Includes mapping of events within a file and relationship of events to similar events in other files  A small database managing a terabyte of data on HP 9000 server

Back-end Implementation (1)  Data structure was redesigned to incorporate other biomedical signals besides ECG signal  Tables were recreated to enable users to query both multiple data files and multiplexed data files which contain multiple channels  Event tables were modified for querying same events in multiple locations within a data file

Back-end Implementation (2)  Views were created for different user groups to query database based on given privileges  Views were created for joining all tables for displaying all data associated with a specific biomedical signal  Indexes were created for primary key, foreign key, and unique constraint  Synonyms were created for each table  Sequences were created for each primary key

Features of Front-end(1)  A front-end web site was developed in Oracle WebDB  The web server is a Windows NT  Users are categorized as public, student, and lab employee with different access privileges to database  Provides query capability and user-friendly data insert interface including BFILE insert

Features of Front-end(2)  Client can download signal data files from query result by secure FTP method  Client can view the ECG Signal on-line based on query result  Client can view all data stored in the database associated with a specific biomedical signal to which he/she has access

Front-end Implementation(1)  Oracle 8i database biomed was created on the web server  Oracle WebDB was installed into the biomed database  Three Data Access Descriptors (DAD) were created to manage three different user groups  Different accounts were created for different user groups with corresponding privileges

Front-end Implementation(2)  A database link and views were created for transferring data between the data server and web server  PL/SQL procedures were developed and WebDB was explored for developing a web-based interface  Java Applets were upgraded to receive parameters  Java Servlets with JDBC were created as an Oracle/Java interface for secure FTP and dynamic signal displaying

Interface to Manage User Groups  Restrict access to interface for student and lab employee by checking login information

Interface to Insert Data  Provides a user- friendly interface to insert data, including BFILE  Data referential integrity is reinforced by displaying foreign keys as LOV, which dynamically select the current entry being referenced

Interface to Query Database  Can query database fields by different condition, such as =, >,, <, in, not in, etc.  Can dynamically query database on various criteria  Can select the output format, including file format and report format

Interface to View Query Result  Can view the query result and choose biomedical signal for further information and operations

Interface to Perform Various Operations  Can choose to download signal files associated with a specific biomedical signal  Can choose to view biomedical signals in all channels for a specific signal record  Can choose to view all information in database regarding a specific biomedical signal

Download Signal File  Can choose channel to download corresponding signal file  Can only download files from the web server without knowing the actual data source

Interface to View Signal Data.  Can select channel to view signal at different speed and different amplitude  Can manually measure signal at both time and amplitude direction  Information is dynamically passed to Java Applet from PL/SQL front-end interface by Servlet

 This database project provides an efficient means to organize the biomedical signal files and related information  The web-based database system built in this project provides a seamless mechanism to search and view the information, and to view the signal on-line  The database provides information about particular medical events which can occur in multiple locations within a file and in different files Conclusions (1)

Conclusions (2)  The framework of organization will allow analysis of biomedical signal for research conducted in the Biomedical Signal Analysis Laboratory  The web-based database project supports on-line class teaching in the area of biomedical signal processing  The web-based database project provides secure public access to a portion of the signal database

Future Work  Link events that occur during one signal file with the graphical interface  Upgrade Java Applet to display more than two channels at the same time for DSI format  Upgrade Java Applet to display data file of size greater than 1 MB for ASCII format  Develop automatic insert routines which both scan the data for relevant information, interpret, and insert into the database  Apply temporal data mining techniques to further research

Acknowledgements  Dr. Wils Cooley  Dr. Bojan Cukic  Dr. Stephanie Schuckers (Chair)  Dr. George Trapp  Dr. John Atkins  Alan Butcher  Dr. Juggy Jagannathan  Qunying Fan  Wei Huang  Members in Dr. Schuckers’ lab