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## Full-Text Articles in Nuclear Engineering

Sensitivity Analysis Approach For Robust Probabilistic Risk Assessment , Shahid Ahmed

#### Sensitivity Analysis Approach For Robust Probabilistic Risk Assessment , Shahid Ahmed

*Retrospective Theses and Dissertations*

The main objective of this investigation is to develop a robust and simplified Probabilistic Risk Assessment (PRA) approach specifically oriented to produce results for risk management decisions of high technology systems. The techniques are based on defining a set of three Significant Indices which quantify the importance of each component, and hence develop a ranking of the components, both with respect to the mean and variance, in the fault tree/event tree structure. The variations in the Top Event probability distribution upon the variations in the component input probability distributions are also evaluated, as well as the first and second ...

Development Of A Polynomial Nodal Model To The Multigroup Transport Equation In One Dimension , Masoud Feiz

#### Development Of A Polynomial Nodal Model To The Multigroup Transport Equation In One Dimension , Masoud Feiz

*Retrospective Theses and Dissertations*

A polynomial nodal model which uses Legendre polynomial expansions was developed for the multigroup transport equation in one dimension. The development depends upon the least squares minimization of the residuals using the approximate functions over the node. Analytical expressions were developed for the polynomial coefficients. The odd moments of the angular neutron flux over the half ranges were used at the internal interfaces, and the Marshak boundary condition was used at the external boundaries. Sample problems with fine mesh finite difference solutions of the diffusion and transport equations were used for comparison with the model.

Vibration Identification Of Nuclear Reactor Components By Statistical Analysis Of Neutron Noise , John Thomas Sankoorikal

#### Vibration Identification Of Nuclear Reactor Components By Statistical Analysis Of Neutron Noise , John Thomas Sankoorikal

*Retrospective Theses and Dissertations*

The possibility of identifying vibrating components, in a nuclear reactor core, through the use of statistical techniques has been investigated. Mechanical vibrations produce neutron noise which appears as fluctuations in detector signals. Theory pertaining to the production of neutron noise is discussed. Vibrations are characterized by location and vibration trajectory parameters. Maximum-likelihood and confidence-region techniques were developed to estimate these parameters. Computer experiments were carried out using simulated detector signals for a simplified reactor model. The sensitivity of the techniques was investigated by parametrically studying the effects of noise level in the detector signal and the presence of external noise ...

Formulation And Analysis Of Higher Order Finite Difference Approximations To The Neutron Diffusion Equation , Mohammed Benghanem

#### Formulation And Analysis Of Higher Order Finite Difference Approximations To The Neutron Diffusion Equation , Mohammed Benghanem

*Retrospective Theses and Dissertations*

Analyses have been made of the truncation error for the following finite difference approximations to the eigenvalue and boundary value problems evolving from the one-group neutron diffusion equation: (i) The seven-point relation; (ii) The fifteen-point relation; (iii) The nineteen-point relation; and (iv) The twenty-seven point relation. These methods have been derived using a Taylor series expansion technique and applied to the Laplacian operator contained in that equation in (x,y,z) geometry for various reactor configurations and boundary conditions;It has been shown that for methods ii and iii, a 4th order truncation error can be achieved, whereas for the ...