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A profile is a resource that allows you to represent a value that varies with time. It consists of a basic pattern that either repeats as a cycle or occurs once and then continues from its last defined setting. Profiles can be either stress profiles, which are used in ALTA life-stress data folios, or throughput profiles, which are used in BlockSim process flow simulation (PFS) diagrams (if supported by your license).
What’s Changed? The profile resource replaces the stress profile functionality that was available in previous versions of ALTA PRO.
This topic describes how to create profiles, which can be defined by entering values manually or by importing data from nCode GlyphWorks.
To learn how to use stress profiles in ALTA life-stress data folios, see Time-Dependent Stress Profiles in the ALTA documentation.
To learn how to use throughput profiles in BlockSim PFS diagrams, see BlockSim Process Flow Simulation Diagrams in the BlockSim documentation.
Like any other resource, you can create or edit profiles from the Resource Manager, or while you’re performing a relevant analysis. To create a profile:
Specify the type of profile that you are creating. If your license does not support BlockSim PFS diagrams, this step is unavailable.
Define a pattern for how a stress or throughput level will change over a specified period of time. The pattern you will define consists of a series of segments, where each segment has a specified duration and either:
a constant stress or throughput value, or
a function that takes a time value and returns a stress or throughput value.
These segments are defined in the spreadsheet, as shown next.
Segment Start is calculated automatically by the software and cannot be entered manually. The first segment's start time is always 0. For every subsequent segment, the start time is identical to the prior segment's end time.
Segment End allows you to enter the end time for each segment, which must be smaller than the end time of the next segment.
Stress S(t) or Throughput T(t) is the stress or throughput value or function for the segment. If the stress or throughput level will stay constant during a segment, enter a constant value (e.g., 30). If the level will change during a segment, enter the value as a function of time (e.g., at time = 20, the function t + 20 will return a value of 40). When entering a function, you must use t or T as the time variable.
Tip: Because stress units (e.g., volts), throughput units (e.g., kilograms) and time units (e.g., hours) are not defined in the profile, it is important to apply profiles only to folios or diagrams that are intended to use the same stress/throughput and time units. In the Profile window, you may want to rename column headings (by right-clicking the heading) or use the Comments page as a reminder of which units are applicable to that profile.
For example, suppose you are creating a stress profile where the stress unit is psi and the time unit is seconds. Now suppose you wanted to define the following 120-second pattern: a stress value of 30 psi for 60 seconds, followed by a stress value of 50 psi for 30 seconds, followed by a stress function that begins at 50 psi and gradually decreases at a rate of 1 psi per second for the remainder of the pattern. For this pattern, you could fill out the spreadsheet as follows:
Notice that the last segment of this profile uses a function. Since t is the test time (or, if the profile is cyclical, the time since the pattern was last restarted), t = 90 when the last segment begins. So the last segment’s stress level starts at 50 - (90 - 90) = 50. Then, at 91 seconds, the stress level will have dropped to 50 - (91 - 90) = 49. After another second it will have dropped to 50 - (92 - 90) = 48, and so on.
Next, choose the appropriate option in the After Last Segment area of the control panel. Your selection here will determine what happens after the end time of the profile’s last segment (in the above example, after time = 120).
If you select Continue with last value, all times after the last segment will use the value/function defined in the last segment.
If you select Repeat cycle, the entire pattern of segments will be treated as a repeating cycle.
For example, suppose you defined a stress pattern that is made up of five segments, each an hour long and increasing stepwise from the segment before. The graphs below illustrate the difference between continuing from the last stress (left) and selecting to repeat (right). In this example, the test has a duration of 20 hours, and the graphs explain what would happen through the entire duration of the test.
Before you can use the new profile in your analysis, you must save any changes you have made and validate the current profile settings. To do this, click the Validate Profile icon.
After you save the changes in your profile, the Profile Summary area will appear. Click the Detailed Summary icon 
to open the Results window, which shows the current profile in a worksheet that you can copy or print.
To view a stress vs. time or throughput vs. time plot of the profile, click the Plot icon. (See ReliaSoft Plot Utilities for general information on plots.)
Note: Clicking the Validate Profile icon will not automatically update your plot. To make sure your plot reflects the most recent profile information, click the Plot icon.
If desired, you can use the Comments page of the control panel to enter notes or other text that will be saved with the profile.
Click OK to save your changes.
You can import nCode GlyphWorks time series data from .S3T files for use as stress profiles. The stress values in the .S3T file must be greater than zero in order for the data to be imported.
To import data from an nCode .S3T file, first create a new profile from the Resource Manager (Home > Synthesis > Resource Manager). In the Profile window, click the Import from GlyphWorks icon on the control panel.
This launches the import wizard, which guides you through the steps required to import data from the file. You can then edit the resulting imported data, if desired. Note that if you update the .S3T file in GlyphWorks, the associated profile in ALTA will not be updated automatically. You must re-import the data to reflect the changes.
Tip: Because stress units (e.g., volts) and time units (e.g., hours) are not defined in the profile, it is important to apply profiles only to folios that are intended to use the same stress and time units. In the Profile window, you may want to rename column headings (by right-clicking the heading) or use the Comments page as a reminder of which units are applicable to that profile.
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