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Description: This paper provides guidance in applying the requirements of DOE O 413.3A to Deactivation and Decommissioning (D&D) projects. A list of 41 engineering and design activities relevant to D&D projects was generated. For several activities in this list, examples of the level of development and/or types of deliverables that might be expected at the completion of the conceptual, preliminary and final project design phases described in the Order are provided.
Date: November 6, 2007
Creator: Santos, J & John Gladden, J
Partner: UNT Libraries Government Documents Department


Description: Building 247-F at SRS was a roughly 110,000 ft{sup 2} two-story facility designed and constructed during the height of the cold war naval buildup to provide additional naval nuclear fuel manufacturing capacity in early 1980s. The building layout is shown in Fig. 1. A photograph of the facility is shown in Fig. 2. The manufacturing process employed a wide variety of acids, bases, and other hazardous materials. As the cold war wound down, the need for naval fuel declined. Consequently, the facility was shut down and underwent initial deactivation. All process systems were flushed with water and drained using the existing process drain valves. However, since these drains were not always installed at the lowest point in piping and equipment systems, a significant volume of liquid remained after initial deactivation was completed in 1990. At that time, a non-destructive assay of the process area identified approximately 17 (+/- 100%) kg of uranium held up in equipment and piping.
Date: May 22, 2007
Creator: Santos, J & Stephen Chostner, S
Partner: UNT Libraries Government Documents Department

Automatic tuning of the reinforcement function

Description: The aim of this work is to present a method that helps tuning the reinforcement function parameters in a reinforcement learning approach. Since the proposal of neural based implementations for the reinforcement learning paradigm (which reduced learning time and memory requirements to realistic values) reinforcement functions have become the critical components. Using a general definition for reinforcement functions, the authors solve, in a particular case, the so called exploration versus exploitation dilemma through the careful computation of the RF parameter values. They propose an algorithm to compute, during the exploration part of the learning phase, an estimate for the parameter values. Experiments with the mobile robot Nomad 200 validate their proposals.
Date: December 31, 1997
Creator: Touzet, C. & Santos, J.M.
Partner: UNT Libraries Government Documents Department

Reinforcement function design and bias for efficient learning in mobile robots

Description: The main paradigm in sub-symbolic learning robot domain is the reinforcement learning method. Various techniques have been developed to deal with the memorization/generalization problem, demonstrating the superior ability of artificial neural network implementations. In this paper, the authors address the issue of designing the reinforcement so as to optimize the exploration part of the learning. They also present and summarize works relative to the use of bias intended to achieve the effective synthesis of the desired behavior. Demonstrative experiments involving a self-organizing map implementation of the Q-learning and real mobile robots (Nomad 200 and Khepera) in a task of obstacle avoidance behavior synthesis are described. 3 figs., 5 tabs.
Date: June 1, 1998
Creator: Touzet, C. & Santos, J.M.
Partner: UNT Libraries Government Documents Department

The application of a microstrip gas counter to energy-dispersive x-ray fluorescence analysis

Description: Performance characteristics of a microstrip gas counter operated as a x-ray fluorescence spectrometer are reported. Gas amplification as a function of microstrip anode-cathode voltage was measured, and the breakdown threshold voltage was determined in pure xenon. The detector temporal stability and the effect of gas purity were assessed. Energy resolution and linearity, detection efficiency, and uniformity of spatial response in the 2- to 60-keV x-ray energy range were determined from the pulse-height distributions of the fluorescence x-ray spectra induced in a variety of single- and multi-element sample materials. Energy resolution similar to conventional proportional counters was achieved at 6 keV.
Date: July 1, 1996
Creator: Veloso, J.F.C.A.; Santos, J.M.F. dos; Conde, C.A.N. & Morgado, R.E.
Partner: UNT Libraries Government Documents Department

Constraints on inelastic dark matter from XENON10

Description: It has been suggested that dark matter particles which scatter inelastically from detector target nuclei could explain the apparent incompatibility of the DAMA modulation signal (interpreted as evidence for particle dark matter) with the null results from CDMS-II and XENON10. Among the predictions of inelastically interacting dark matter are a suppression of low-energy events, and a population of nuclear recoil events at higher nuclear recoil equivalent energies. This is in stark contrast to the well-known expectation of a falling exponential spectrum for the case of elastic interactions. We present a new analysis of XENON10 dark matter search data extending to E{sub nr} = 75 keV nuclear recoil equivalent energy. Our results exclude a significant region of previously allowed parameter space in the model of inelastically interacting dark matter. In particular, it is found that dark matter particle masses m{sub x} {approx}> 150 GeV are disfavored.
Date: November 23, 2009
Creator: Angle, J; Aprile, E; Arneodo, F; Baudis, L; Bernstein, A; Bolozdynya, A et al.
Partner: UNT Libraries Government Documents Department