dbMASS 4.1
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This file documents the enhancements and problem fixes provided with dbMASS version 4.1. Please read to stay up to date on these developments.

dbMASS 4.0 Special Note

A problem was identified with the initial release of dbMASS 4.0 which could cause an improper status flag setting when the data was converted to the new database format. Please read the Database Conversion Fix notes on how to restore this data to the database. We apologize for any inconvenience this situation may have caused you.

CONTENTS

----------------------------------------------- Version / Published

    ------------------------------------------------- 4.10 / February 28, 2001

  1. New Features
    1. Message Prior to Update
    2. MPEX Format
      1. PURGE Parameter
      2. Export Availability
      3. Transformation Matrices
      4. Blank Items
    3. Memory Optimization
  2. Bug Fixes
    1. Database Conversion Fix
    2. Location Specific Class Category Message
    3. MPEX Format
      1. ADD FIELDS Data Set
      2. Mass Item Status
    4. Unassigned Entries Listing

      5. ------------------------------------------------- 4.11 / March 10, 2001

    5. Mouse Click Response

      6. ------------------------------------------------- 4.12 / March 13, 2001

    6. CATIA and IDEAS Translators
    7. Large Number Display Issue
    8. Spelling Correction

      9. ------------------------------------------------- 4.13 / March 15, 2001

    9. MPEX Format
      1. CG Located Entries
      2. Long Notes

1. New Features

  1. Message Prior to Update

An "attention" message now appears after selecting the Database Update command. This message recommends that the database be backed up prior to running the update. This practice of backing up the data is encouraged so that changes caused by the update can be identified by comparing reports generated on the before and after databases. The message also asks whether to continue with the update. Selecting "no" will abort the update operation so that a backup can be created. Use the Database Copy command to create a backup.

  1. MPEX Format

Several modifications and enhancements to the MPEX format support have been made. These modifications are as follows:

PURGE Parameter. The MPEX format has been enhanced to support a PURGE parameter for the "WEIGHT STATUS" and "MATERIALS" data sets. The parameter, PURGE, when provided is used to indicate that any previously defined weight status categories or materials should be deleted prior to adding the new ones provided. The use of this parameter will cause the default contingencies and/or materials to be deleted from the new database created from the MPEX data. This will ensure that the MPEX data will appear in the order listed in the MPEX data file.

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Export Availability. Previously only users with modify permission to a database could export the data to the MPEX format. This restriction has been removed so that now any user with read access would be able to use the MPEX export feature.

Transformation Matrices. Normally a transformation matrix is only created and stored in dbMASS as needed. However, while importing coordinate transformation information from the MPEX format, transformation matrices were being stored in the database to maintain the scaling factors even when they were all set to unity. The unity scale factor is assumed if none is provided (blank data column). The MPEX translator now recognizes this condition and will not add a transformation matrix unless angular rotations are involved or non-unity scale factors are provided.

Blank Items. In a similar situation to the transformation matrices, blank items were being added to all parts. This condition has been corrected so that only items provided through the ITEMS data set are added. An item will also be added to a part if full mass properties are provided with a material assignment given in the ENTRIES data set. For this situation, an inertia shape will be created for the part.

  1. Memory Optimization

In an ongoing effort to make dbMASS faster and more memory efficient many infrequently used dbMASS text messages are now stored off to disk to leave more RAM space available.

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2. Bug Fixes

  1. Database Conversion Fix

In the process of transferring data to the new database format provided with dbMASS version 4.0 the mass item status of some parts was not properly maintained. The mass item status is used to track whether the mass properties of a part are either entered or calculated values. Not having this field properly set could cause the user defined mass properties to be overwritten with calculated values under several situations. For example, running the Database Update command and requesting that the parts mass properties be recalculated will cause the user defined values to be lost if the mass item status was not properly transferred. Also editing an item of a part or modifying a material density could also cause user defined values to be lost.

There are two methods by which the mass item status can be restored. The first method requires that the database used to create the new database is still available. If you do not have the original database, you will need to resort to the second method to protect the user defined mass properties. The first method is much preferred.

Preferred Method

To restore the mass item status from the original database you will need to locate its "descrpxx.dbm" file where xx is the two-digit number assigned to the database files. You can determine the database number by viewing the catalog file for the database. Catalog files have the ".cat" extension and are found in the directory containing the database. You can view the catalog files with any text editor, e.g. Notepad. Identify the correct catalog by noting the description. The first text in the catalog file gives the database description. The balance of the catalog file provides a list of database files. Note the two digit value that is assign to the files. Using the two digits identified, make a copy of the corresponding "descrpxx.dbm" and rename it to "descrppv.dbf" (not case sensitive). If not already there, move this file to the directory containing the version 4.0 database you wish to repair. Then start dbMASS v4.1 or later. Make the database you wish to repair active by using the Database Select command if not already active. Create a backup if you don't already have one then run the Database Repair command. This will scan the original database file and restore the mass item status for all parts. Parts that you may have changed to mass items after the conversion process will not be affected by this repair operation. This process does not restore the original mass properties for any parts that may have had their mass properties recalculated prior to running this repair.

To test the result, note the mass properties of the top-level entries and then run the Database Update command with the recalculation of the parts. Compare the before and after mass properties. They should be the same. If not, you will need to identify which entries mass properties changed and why.

Delete the "descrppv.dbf" file after you have completed the repair.

Second Method

Use this method to restore the mass item status of parts only if you no longer have access to the original version 3 database. This method entails exporting the version 4 database to the MPEX format, making modifications to the data and then importing the resulting MPEX formatted data file.

After exporting the database using the Database Export command, open the resulting "mpexport.txt" file with Excel. The Text Import Wizard will automatically start. Move the wizard to the third step in the process by selecting the next button. If you use the equals, plus or minus (=, + or -) characters as the first character in any description you will need to make sure that the columns containing this data are interpreted as text. This can be done during the third step of the Import Wizard process, which supports specifying the column data type. One of the best methods to ensure that all data will be interpreted correctly is to indicate that all columns are text. To do this, scroll down to the ENTRIES data set and then select all columns by using a shift-click on the header of the last column of data. Once the columns are highlighted, select the Text format type. Then select the finish button to complete the Text Import Wizard process.

Now scroll down to the ENTRIES data set and note which spreadsheet column contains the "overtyped" status. You will need to set this column data to one for all parts that you know have user entered (not calculated) mass properties. If you consistently assign certain contingency types with user entered mass properties in dbMASS, you can search for the entries with those assignments given in the Weight Status column. Another option would be to set the "overtyped" status for all entries that have a Weight Status assignment since only parts will have an assignment. If neither of these approaches helps you identify the "overtyped" parts, you will need to identify them by other means. It is better to error on the side of caution by marking parts as "overtyped."

Once the "overtyped" status adjustments have been made save the file as a tab delimited text file. (You may also want to save it as a spreadsheet file should you want to come back to it later.) Close the spreadsheet after saving it.

Then import the updated MPEX file into dbMASS using the Database Import MPEX command. After the import is completed, compare the resulting mass properties of the top-level entries to see if they remain unchanged. If they do change, you will need to create a mass properties report on the corresponding top level entry and compare it to one on the original version 4.0 database. The best method for comparing the reports is to use the tab delimited report format when creating the reports and then to bring the reports into Excel for comparison.

  1. Location Specific Class Category Message

During the class category flow up process a select category message is sometimes displayed to allow the user to select the appropriate category for a specific instance/location of an entry. A problem was introduced in dbMASS 4.0 that caused this message to be blank. This problem has been corrected.

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  1. MPEX Format

A few problems with the MPEX export/import features have been identified and corrected. Here is a brief description of the conditions corrected.

ADD FIELDS Data Set. dbMASS uses the ADD FIELDS data set to add fields to the ASSEMBLIES and ENTRIES data sets. However, if the numeric method was being used to designate parent-child relationships these data sets take the form of ASSEMBLIES* and/or ENTRIES*. For these forms of the data sets  the added fields were not being recognized. This situation has been corrected so that now both forms of the data sets reflect the fields specified with the ADD FIELDS data set.

Another situation that was corrected when writing the ADD FIELDS data set was the removal of the trailing asterisk (*) character from the descriptions of the fields associated with the locations. dbMASS uses the trailing asterisk character so that the instance/location fields can be distinguished from the entry fields in the reports. The asterisk is automatically added to the description when the field is added and therefore should not appear in the description.

Mass Item Status. The mass item status (overtyped flag) for items mass properties was not being set properly when importing MPEX data. It was being set to TRUE but needed to be set to a specific value used by dbMASS to recognize the items weight status.

  1. Unassigned Entries Listing

The unassigned entries list provided in the class based (maturity) reports was indenting some of the entry descriptions relative to the id. This situation has been corrected so that now all entry descriptions will start in the same column.

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  1. Mouse Click Response

A significant delay was being experience after mouse click operations prior to performing the selected action.  This problem surfaced with dbMASS 4.0 Beta1 but has now been isolated and repaired. The lighting quick response of dbMASS has been restored.

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  1. CATIA and IDEAS Translator

A couple of new fields introduced with dbMASS 4.0 for tracking the overtyped status and cg location mode were not being properly set for data imported via the IDEAS and CATIA translators. This problem has  been isolated and repaired.

  1. Large Number Display Issue

The Units Window is used to set the number of significant figures and the precision for numbers displayed on the screen and to reports. The number of significant digits was incorrectly being limited to one for numbers that were greater than 2,147,483,647 no matter what the Units Windows specified. This problem has been corrected.

  1. Spelling Correction

A minor spelling error was correct in the "Transferring entries..." message posted when data is being transferred between databases.

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  1. MPEX Format

A few problems with the MPEX export/import features have been identified and corrected. Here is a brief description of the conditions corrected.

CG Located Entries. The dbMASS MPEX Translator was not correctly storing the cg located entries when specified by the cg mode field in MPEX formatted data. All appeared to be fine when the data was first imported, however, running the Database Repair command identified the anomaly and repaired it by clearing the setting. The MPEX Translator has been fixed to correctly store the cg mode status.

Long Notes. Notes which where longer than 80 characters caused a few problems for the MPEX export and import process. The symptoms included the addition of trailing quotation marks to notes or invalid record numbers. The problems have been corrected so that text notes of up to 1020 characters are supported.

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