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3.9 Implementation of a Web Interface to the SRSM

All numerical routines associated with the development of the SRSM have been incorporated into a a stand-alone application, that could be used for uncertainty propagation with black-box models. This has also been implemented as a ``Web Based'' tool, that can be run from remote web browsers. The interface was implemented by using the Common Gateway Interface (CGI) programming using the Perl language. An operational version can be accessed through the location

http://www.ccl.rutgers.edu/srsm.html

The web server is located in the Computational Chemodynamics Laboratory, at the Environmental and Occupational Sciences Institute, a joint project of University of Medicine and Dentistry, New Jersey, and Rutgers, The State University of New Jersey.

Here, the application of the SRSM method for a simple black-box model is presented. In order to use the SRSM, first the number of inputs, their probability distributions, the number of outputs, and the order of polynomial chaos expansion desired, have to be specified, as shown in Figure 3.4. The program responds with the recommended sample points, and the model outputs at these sample points have to be input, as shown in Figure 3.5. Additionally, a range for plotting the output probability density functions is also required as input. The program uses the model outputs at these sample points and calculates, and displays the probability density functions for each of the outputs, as shown in Figure 3.6.

**Figure 3.4:** Application of the web based SRSM tool: specification of input uncertainties
$\begin{figure} \centerline{\epsfig{figure=srsmwebin.eps,width=5.5in}} \par\end{figure}$

**Figure 3.5:** Application of the web based SRSM tool: recommended sample points and the corresponding model outputs
$\begin{figure} \centerline{\epsfig{figure=srsmwebcol.eps,width=5.5in}} \par\end{figure}$

**Figure 3.6:** Application of the web based SRSM tool: estimates of the pdfs of the outputs
$\begin{figure} \centerline{\epsfig{figure=srsmwebout.eps,width=5.5in}} \par\end{figure}$

Next: 4. COUPLING OF THE Up: 3. THE STOCHASTIC RESPONSE Previous: 3.8 Computational Implementation

Sastry S. Isukapalli
1999-01-19