1. Mohammad Khalessi, Ph.D. CEO/President PredictionProbe, Inc.
Conference on Quality in Space & Defense Industries CQSDI ‘08 Probabilistic Technology Panel: What Is Probabilistic Technology?
Mohammad Khalessi, Ph.D.
CEO/President
PredictionProbe, Inc.

2. Probabilistic Technology*
07/16/96
Probabilistic Technology
Y1, Y1, …
Probabilistic Technology is a set of advanced predictive methods that allow for integration of uncertainties into process models and evaluation of the effects
Input
X1, X2, ….
PROCESS
Y = f (X1, X2,…)
Output
Y1, Y2, …
Step 1
Step 3
Step 4
Step 2 l
Utilizes physics laws, process rules, or empirical modeling techniques to construct process/output models
Utilizes probability law to construct statistical models for Input Variables
 2007, PredictionProbe, Inc. All rights reserved. * 9 17

3. Probabilistic Technology Optimizes Design, Performance, Number of Tests and More
Probabilistic Technology provides 3 metrics to quantitatively evaluate design early in the decision process when no data is available
1. Most-Probable-Points
Safety control systems
Certification tests
Reliability demonstration tests
Critical combination of parameters
Most likely failure points
Many more
Performance level = C1
Performance level = C2
2. Probability Information
Reliability, risks, failure prob.
Critical failure modes ID
Performance range
Most-likely performance value
Safety-factor calibration
Many more
3. Process Sensitivity Measures
Key process variables & uncertainties
Guidelines to develop test plans
Guidelines for inspection & repair planning
Guidelines to develop improvement plans
Guidelines to develop control plans
Guidelines to develop monitoring plans
Many more
 2007, PredictionProbe, Inc. All rights reserved.

4. Probabilistic Technology Allows for Safer and Lighter Designs
Uncertainties significantly impact the prediction accuracy. Probabilistic Technology can accurately identify the failure location and the magnitude of failure probability.
Press COV = 10%
Axial Load COV=5%
Failure Prob. = 1.4%
Press COV = 5%
Axial Load COV=20%
Failure Prob. = 3.5%
Press COV = 5%
Axial Load COV=5%
Failure Prob. = 0.7%
Finite element model
of a fuel tank
 2007, PredictionProbe, Inc. All rights reserved.

5. Probabilistic Technology Eliminates or Minimizes Costly Changes*
07/16/96
Probabilistic Technology Eliminates or Minimizes Costly Changes
 2007, PredictionProbe, Inc. All rights reserved. * 57 65