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Wraps. Presumed first edition/first printing. 77, [3] p. Includes illustrations. Some illustrations in color. References. This report described the underlying principles and goals of the sandia Accelerated Strategic Computing Initiative (ASCI) Verification and Validation Program Validation Metrics Project. It also gives a technical description fo two case studies, one in structural dynamics and the aother in theromomechanics, that serve to focus the technical work of the prject in Fiscal Year 2001. Good. No dust jacket. Staple bound.

Zustand: New. pp. 424.

Zustand: New. In.

Spiral bound. Zustand: Very good. Presumed First Edition, First printing. x, 101, [1] pages. Tables, Figures. References. Appendix A: Model Parameters. Appendix B: Measurements, Predictions, and Sensitivities. CPUF/COYOTE model predictions were compared to experimental observations for the progression of a foam decomposition front due to heating from one side at 600 C, 750 C, and 900 C. We began with the characterization of the uncertainty for the model predictions due to uncertainty in model parameters. A first order sensitivity analysis and Monte Carlo simulation were used to estimate the structure of the uncertainty in the model predictions for the front motion due to parameter uncertainty. The resulting distributions were found to be normally distributed, correlated, with non-uniform variances. The metrics of Hills and Trucano (1999, 2001) were used to evaluate the consistency of the model predictions with the experimental observations for eight experiments. Mixed results were found depending on which experiment was considered. The model predictions for the 900 C experiment were found to be inconsistent with the experimental observations for the uncertainty models developed here. A locally linear analysis for the 600 C experiments indicated that the corresponding model predictions had very large uncertainty, and predictions and experimental observations were found to be consistent within this large uncertainty. Experimental results were analyzed for multiple orientations of the 750 C test cases. The results were mixed with the model tending to perform better for vertical orientations (heated from below or above) of the foam-in-can experiment.

Paperback. Zustand: Brand New. 424 pages. 9.21x6.14x0.87 inches. In Stock.

Zustand: New. In.

Hardcover. Zustand: Brand New. 1st edition. 402 pages. 9.50x6.25x1.00 inches. In Stock.

Spiral bound. Zustand: Very good. Presumed First Edition, First printing. xi, [1], 176 pages. Nomenclature. Tables. Figures (some with color). References. Appendices. A case study is reported to document the details of a validation process to assess the accuracy of a mathematical model to represent experiments involving thermal decomposition of polyurethane foam. The focus of the report is to work through a validation process. The process addresses the following activities. The intended application of mathematical model is discussed to better understand the pertinent parameter space. The parameter space of the validation experiments is mapped to the application parameter space. The mathematical models, computer code to solve the models and its (code) verification are presented. Experimental data from two activities are used to validate mathematical models. The first experiment assesses the chemistry model alone and the second experiment assesses the model of coupled chemistry, conduction, and enclosure radiation. The model results of both experimental activities are summarized and uncertainty of the model to represent each experimental activity is estimated. The comparison between the experiment data and model results is quantified with various metrics. After addressing these activities, an assessment of the process for the case study is given. Weaknesses in the process are discussed and lessons learned are summarized.

Staplebound. Zustand: Very good. Presumed First Edition, First printing. 72, [2] pages, including covers. Illustrations (some with color). References. Mailing label on back. Staplebound. Unlimited Release. Enhanced software methodology and improved computing hardware have advanced the state of simulation technology to a point where large physics-based codes can be a major contributor in many systems analyses. This shift towards the use of computational methods has brought with its new research challenges in a number of areas including characterization of uncertainty, model validation, and the analysis of computer output. It is these challenges that have motivated the work described in this report. Approaches to and methods for model validation and (model-based) prediction have been developed recently in the engineering, mathematics and statistical literatures. In this report the authors have provided a fairly detailed account of one approach to model validation and prediction applied to an analysis investigating thermal decomposition of polyurethane foam. A model simulates the evolution of the foam in a high temperature environment as it transforms from a solid to a gas phase. The available modeling and experimental results serve as data for a case study focusing on model validation and prediction developmental efforts on this specific thermal application.