EARTHWORM5 QUICK REVIEW

Document Version 1.0 (2000/09/15)


1.	OBJECTIVE

The objective of the Earthworm5 Quick Review (EQR) is to provide Earthworm with a remote, 
rapid event review capability. Its intended use is permit a duty seismologist to rapidly respond to 
a significant event. It was not designed to serve as a routine analysis facility, as there are 
substantial ongoing efforts to provide such capabilities. 
Its features include:
	* Requires only browser access to the Internet.
	* Interacts with events via the Earthworm DBMS.
	* Viewing and editing of automatic event parameters.
	* Graphic re-picking.
	* Event relocation and re-insertion into DBMS.
	* Supports both low- and high-bandwidth connections.
	* Supports interlocks for concurrent reviewers.


2.	SYSTEM OVERVIEW

The EQR system works by allowing the analyst to retrieve an event from the DBMS, modify its 
parameters, relocate the event, and subsequently decide whether to reinsert the new solution or to 
delete the event from the DBMS.

The basic editing mechanism is the Hypoinverse Archive File (Arc) format. Retrieved events are 
written in Arc format on the WWW server's local disk. The reviewer can then manually edit that 
file (e.g., with vi or textedit), or use the suite of web-based review tools which allow the user to 
graphically modify the event, while at the same time updating the underlying Arc file. 

The Text-based and Web-based review methods (described in detail below) are based on the 
same suite of library routines. This enables the programmer to efficiently modify the review 
system, as change to a single routine affects both review methods.


3.	TEXT-BASED REVIEW

3.1. CONFIGURATION AND DIRECTORY STRUCTURE

Text-based EQR needs a single configuration file with the following parameters:




# configuration file for text based event review


#
# Database connection parameters
#
#
DBuser     p3_main
DBpassword main
DBservice  eqsg.usgs

#
# Logfiledir - where log files are written
#
Logfiledir ./log/

#
# Debug (OPTIONAL)
#
Debug    1

#
# ArcFileName: Full path to the name of the Hypoinverse ARC file
#   in which the event info is written
#
ArcFileName   /tmp/ArcFile


Besides the typical Earthworm% directory structure, no further special directories are needed, 
except for the directory where the ArcFileName file is located. Note that the directory where the 
Arc file will be written must exist and must be writeable to the user operating EQR.

3.2. COMMANDS

The following programs make up the text-based EQR. The source code is located in:

$EW_HOME/$EW_VERSION/src/oracle/apps/src/review/text

The default location for compiled binaries is: 

$EW_HOME/$EW_VERSION/bin



3.2.1.	DB2FILE

db2file retrieves an event from the database and writes it to the local disk in the hypoinverse 
archive format in the file specified by the ArcFileName parameter.

Usage:    
db2file configuration_file event_id

3.2.2.	DELETE_EVENT

delete_event deletes the event from the database.

Usage:
delete_event configuration_file event_id

3.2.3.	FILE2DB

file2db inserts the information about the event described by the hypoinverse archive file arc_file 
into the database. Note that the event_id of the event to be inserted should be in the Arc file.


Usage:    
file2db configuration_file arc_file


3.3. TYPICAL REVIEW SEQUENCE

To review the event with event_id 1001, using the parameters in the configuration file 
text_review.d above:

# db2file text_review.d 1001       (retrieve event information)
# vi /tmp/ArcFile                  (edit the pick parameters)
# hyp2000                          (run hypoinverse to relocate the event)
# ls hypo.arc                      (output Arc file from hypoinverse)
# file2db text_review.d hypo.arc   (insert event info into DBMS)






4.	WEB-BASED REVIEW

4.1. PROGRAMS

The following programs make up the web-based EQR. The source code is located in:

$EW_HOME/$EW_VERSION/src/oracle/apps/src/review/web

The default location for compiled binaries is: 

$EW_HOME/web/bin

The configuration files must be located in: 

$EW_HOME/web/params

4.1.1.	GETLIST_REVIEW

Uses configuration file named getlist_review.d identical to the one used by getlist in the original 
DBMS web pages.

Similar in function to getlist in the original DBMS web pages, this program produces HTML to 
display a list of events in the database which fit specified criteria such as location, depth, 
magnitude, and event time limits. 

To accommodate a wide range of bandwidth requirements, the default start page is produced 
without a map of the default region. The user is allowed to click on the link at the top of the page 
which causes the ShowMap Web option to be set before re-invoking getlist_review. In this 
mode, a clickable map of the default region is shown, allowing the user to select an event for 
review either by clicking on the event on the map, or by clicking on the link of the EventID in 
the list of events.

Either mode of selecting an event for review invokes eqreview.

4.1.2.	EQREVIEW

Very similar to eqparam2html in the original DBMS web pages, it uses configuration file named 
eqreview.d of the following format:


#
#  Configuration file for eqreview
#

#
# Database connection parameters
#
DBservice       eqsg.usgs
DBuser          p3_main
DBpassword      main

Debug
Logfiledir      ../log/

#
# hostname of the machine holding up web pages
#
WebHost		gldzappa.cr.usgs.gov


#
# Directory where temporary review files are written. This is 
# where Arc files, as well as SAC files for each arrival are
# temporarily stored
#
# NOTE: this directory must be under the web's earthworm directory
#  because this is where the review applet needs to find the 
#  SAC files
#
ReviewDir           /home/earthworm/web/html/review

#
# WebDir: Web mapping of ReviewDir
#
WebDir				/earthworm/review

#
# Full path to the hypoinverse program
#
PathToHypoBin		/home/earthworm/working/bin/hyp2000


#
# Full path to the hypoinverse directory
#
HypoinverseDir		/home/earthworm/web/params/hypoinverse

#
# Name of the hypoinverse configuration file
#
HypoConfig		ncal2000.hyp


#
# Name of the file containing Lomax javascript. 
# NOTE: It must exist under ReviewDir/lomax
#
#
JavascriptFile		lomax_new.js

#
# Output format (platform): sparc or intel
#
SacFormat		sparc


eqreview, when first invoked from getlist_review, runs in the GetFromDB mode where creates a 
review directory for this event under the directory specified by the parameter ReviewDir/tmp. 
The event's review directory is named after the event's database EventID.
 
Into the newly created event review directory, eqreview retrieves the information about the event 
from the database and writes it as a hypoinverse archive file named. Also, for every available 
trace snippet, a SAC file is written into the same directory.

Then, eqreview produces HTML to display the parameters of the event, such as location and 
magnitude, as well as detailed parameters for each pick. The resulting page allows the user to:  
-	modify the event's magnitude, 
-	delete each pick,
-	modify the time of each pick, and
-	modify the weight of each pick.


For each available trace snippet, the user is able to invoke the SeisGram2K applet (written by 
Anthony Lomax) by clicking on the hyperlink over the name of the channel. See Section 4.1.2.1 
below for more information on the SeisGram2K applet.

4.1.2.1. SeisGram2K applet

SeisGram2K is a Java applet written by Anthony Lomax. The applet is invoked by clicking on an 
HTML link which formats the command line and passes along the name of the SAC file 
containing the trace and parametric data for a channel. eqreview produces HTML code 
necessary to invoke the applet. The necessary Java code to run the applet is in the JAR file. Some 
additional Javascript code needs to be incorporated into the HTML code in order to invoke the 
applet.

To that end, the eqreview.d configuration file parameter JavascriptFile should contain the name 
of the file with the javascript code. Within the javascript code the name and location of the JAR 
file must be specified.

SeisGram2K makes web requests to the server to retrieve the SAC file and also to send back to 
the server the modified pick information. To accomplish this, the parameter WebHost must be set 
to the name of the web server running the review system, and WebDir must be the top level of 
the review directory tree as it is mapped by the web server.

After the user is finished repicking a channel using SeisGram2K, the user can send back the 
updated information. SeisGram2K is passed the name of the CGI program on the review server – 
retrieve_pick – which updates the ArcFile and the SAC files on the server with the new pick 
information (See section 4.1.6 for more details).


4.1.2.2. Buttons

The web page produced by eqreview contains three buttons: Refresh, Cancel, and Done. They 
are implemented as a web-form which invokes the program review_process with appropriate 
arguments. 

4.1.2.3. Operating Modes

eqreview operates in several modes:

a)	GetFromDB. Retrieves event information from the database, saves it in the ArcFile and 
SAC files, saves the original author of the event in the file Author, and continues in the 
Refresh mode.
b)	Override. If the temporary event directory already exists, someone else might be 
reviewing that event, or the directory was left over from an abnormal termination of the 
review process. In this mode, the user is told about the conflict and allowed to click on a 
link which causes the offending directory to be removed. From there on, eqreview 
proceeds as if it were in GetFromDB mode.
c)	Relocate. Invokes the hypoinverse program which must be located in the place specified 
by the PathToHypoBin parameter. Hypoinverse relocates the event based on the 
information in the ArcFile, and based on the hypoinverse parameters specified by the 
HypoConfig parameter.  The archive file resulting from the relocation is copied over the 
original ArcFile, and eqreview continues in the Refresh mode.
d)	Refresh. This is the default mode where eqreview reads the ArcFile and produces HTML 
with modifiable event information based on the ArcFile.

4.1.3.	REVIEW_PROCESS

review_process is an intermediate processing step. It is called from eqreview and passed a series 
of arguments:
-	EventID
-	Potentially modified magnitude
-	List of potentially modified pick times and weights
-	List of picks to delete
-	Action parameter: Refresh, Cancel, or Done

4.1.3.1. Cancel

If the user pressed Cancel in eqreview, review_process removes the temporary review directory 
for this event and displays HTML explaining this operation to the user. This is the end of the 
review chain for this event. The local disk has been cleaned up, and no changes to the event were 
made in the database.

4.1.3.2. Refresh

Clicking Refresh causes review_process to produce a simple HTML page which contains a link 
back to eqreview invoking it in the Refresh mode.

4.1.3.3. Done

If the user clicked Done in eqreview, review_process reads the original ArcFile and updates it 
with the new magnitude and pick information. Then, the user is presented with three buttons 
allowing the user to chose what to do with the modified ArcFile. The buttons are: Relocate, 
Delete, and Reinsert. 

Clicking on Relocate invokes eqreview in Relocate mode. 

Clicking on Delete or Reinsert invokes the program confirm with the appropriate parameters.

4.1.4.	CONFIRM

This is a very simple program which merely puts up HTML to prompt the user to confirm the 
choice to delete or re-insert the event, made in review_process. confirm may be invoked in two 
modes, Delete or Reinsert. In either case, the user is presented with two buttons: One to confirm 
the operation, and one to cancel.

If the user clicks Cancel, eqreview is invoked in the Refresh mode. This shows the user the 
original page with modifiable event information. From here the user can either continue the 
review process, or terminate it by clicking Cancel.

If the user confirms the operation, the program process is invoked with appropriate parameters.

4.1.5.	PROCESS

This is where the real work of deleting or inserting the event is done. process can be invoked in 
two modes: Insert or Delete.

In the Insert mode, process reads the ArcFile and makes the appropriate API calls to insert the 
information from the ArcFile into the database. Note that the author field of the new Origin is 
created by prepending the string REV_ to the original author field, saved in the file Author, to 
signify that this event is being re-inserted into the database after it was reviewed by a human.

In the Delete mode, process makes the appropriate API calls to delete the event from the 
database. 

Upon completion of either operation, process produces HTML informing the user of the 
operation, and then deletes the temporary review directory for the event. This is the normal 
termination point of the review process for this event.


4.1.6.	RETRIEVE_PICK

This program is called by the SeisGram2K applet in order to send the modified pick information 
back to the server. retrieve_pick reads from standard input a single line formatted in the 
modified NON_LIN_LOC format. The input contains the information about the picks that the 
user defined for the given channel of data. 

This input line is first parsed, and then retrieve_pick updates the information in the SAC file 
associated with that channel, and also in the ArcFile.


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