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Neutron Capture Cross Section Measurements of 243Am For Neutron Energies up to 1 MeV at Dance With a Novel Technique on the Preparation of Actinide Targets
No full textNeutron capture reactions of actinides are of great importance for different applications in nuclear physics and stockpile stewardship. In the absence of underground testing, the safety, security, and reliability of the nuclear stockpile resides in the use of simulations and the application of scientific knowledge about the physical and chemical properties of the actinides to the specific problems of weapons aging. ^243Am has proven to be an important actinide whose neutron capture cross section is especially important. However, due to the actinides��� characteristics (radioactive, limited quantity, price, etc.), acquiring appropriate targets for these experiments has proven to be challenging.
This thesis is divided into two parts. The first part contains a detailed description of a neutron capture cross-section measurement on ^243Am that took place at LANSCE, using the DANCE (Detector for Advanced Neutron Capture Experiments) array during the 2007 run cycle. The analysis and results from this experiment showcase the importance of appropriate targets, without which reliable cross-sectional data cannot be produced. The second part describes the development of a new target preparation method using spraying-assisted solution combustion synthesis. With this method, robust actinide targets of desired thicknesses and with the desired properties can be produced. Additionally, a complete characterization process was also developed, in order to fully characterize the produced targets regarding their thickness, composition, microstructure and uniformity. Finally, two new targets of ^243Am and ^243Am/^235U were produced for a new neutron capture cross-section measurement that will take place at LANSCE using the DANCE detector array and the new spallation source MARK ��� IV
Smart Manufacturing Plant Floor Cybersecurity
Get PDFCybersecurity for plant floors have received little attention across the manufacturing digital thread and the physical supply chain. Machine tool controllers (MTCs) are an ubiquitous component of plant floors and have historically been primary targets for cyberattacks leading to supply chain disruption, plant failures and fatal accidents. This gap in cybersecurity for MTCs opens a critical and interesting avenue for interdisciplinary research to investigate cybersecurity techniques for protecting the manufacturing systems and processes against looming cyberattacks.
The subject of this dissertation is to present techniques for detecting anomalous behaviors from cyberattacks using machine data and physical data. Motivated by challenges of a closed architecture MTC and aimed towards cybersecurity assurance, a framework of an MTC emulator for a 2-axis contouring system is presented. The emulator is a surrogate system which avert costly machine downtime and safety hazard from hosting and detecting cyberattacks. The emulator tracks measured path trajectories up to 0.23 mm accuracy for various geometries tested. Following this, the technique of dynamic watermarking (DWM) using machine data for protecting MTC against cyberattacks is introduced for the developed emulator alongside the associated attack detection tests. Here, an implementation of DWM for open architecture controllers is also presented. The technique of DWM can detect infamous cyberattacks with average delay of 0.15s on the developed emulator. Similar performance is noted for DWM on open architecture MTCs. Finally, a novel unsupervised spectral-banding technique is developed for frequency domain monitoring of physical data from manufacturing processes. This technique uses Bayesian optimization to identify parametrized spectral-bands for optimally discriminating between anomalous and normal process operating conditions. This dissertation unveils novel techniques and advances their state-of-art application for securing plant floor MTCs using machine data and physical data for open and closed architecture MTCs
25 HOUSTON ZIP CODES: A COMMUNITY LEVEL PUBLIC POLICY ANALYSIS
No full textThis analysis captures trends from specific areas of Houston, including two key influencers, (1) city government is in business for itself, and (2) lack of job development is a specific area resulting in unstable resource pools and a substantial toxic disconnect with elected officials and stakeholders. The prevailing jurisdictional edicts produce a steady diet of temporary fix initiatives. And declining public safety and health services.
Surveys conducted by Charity Productions over the past nineteen years with homeowners, renters, and local businesses, provided great insight from a bottom-up perspective. These surveys become a part of the community institutional bank of knowledge on how gaps in service delivery consistently fails. The survey results overtime has revealed a fill in the blank puzzle of rotating priorities. Any four areas are laced with companion subset issues depending on the neighborhood.
We are at the dawn of a New Age to find the missing links reducing disparity���s grip on underserved neighborhoods. This analysis uncovered a translation of service delivery DNA markers to an operational vehicle that reduces inequities. A change in the operational aspects will improve the change of the culture and climate of service delivery to underserved neighborhoods. Changing the trajectory of research from a bookshelf, of potential new research grants into a functional data transformation center of exchanges with sustainable field-tested program outlets.
In this new age will introduce new terms, redefine old terms and clarify mis-defined phrases. These proclamations will be accomplished by using an arrangement of proven and accepted practices starting with evidence-based approaches to problem solving and service delivery at the neighborhood level listed as hard to serve