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Risk Analysis Commons

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University of Tennessee, Knoxville

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Articles 1 - 8 of 8

Full-Text Articles in Risk Analysis

Flight Risk Management And Crew Reserve Optimization, Ying Zhang Aug 2017

Flight Risk Management And Crew Reserve Optimization, Ying Zhang

Doctoral Dissertations

There are two key concerns in the development process of aviation. One is safety, and the other is cost. An airline running with high safety and low cost must be the most competitive one in the market. This work investigates two research efforts respectively relevant to these two concerns.

When building support of a real time Flight Risk Assessment and Mitigation System (FRAMS), a sequential multi-stage approach is developed. The whole risk management process is considered in order to improve the safety of each flight by integrating AHP and FTA technique to describe the framework of all levels of risks ...


Integrating Disparate Nuclear Data Sources For Improved Predictive Maintenance Modeling: Maintenance-Based Prognostics For Long-Term Equipment Operation, Zachary Allen Welz Aug 2017

Integrating Disparate Nuclear Data Sources For Improved Predictive Maintenance Modeling: Maintenance-Based Prognostics For Long-Term Equipment Operation, Zachary Allen Welz

Doctoral Dissertations

The United States (US) nuclear industry is one of the most heavily regulated businesses in the world, creating a culture of world-class design, operation, and maintenance. In an article published on modern maintenance technologies, Terrence OHanlon (past Chief Asset Manager for Reliabilityweb.com) stated, “world class companies often devote up to 50 percent of their entire maintenance resources to condition based monitoring and the planned work that is required as a result of the findings” [1]. One would expect US nuclear power plants to constantly upgrade, improve, and expand their operations and maintenance departments and tactics. Since the early 1990s ...


Nuclear Power: Black Sky Liability Or Black Sky Asset?, Sherrell R. Greene Dec 2016

Nuclear Power: Black Sky Liability Or Black Sky Asset?, Sherrell R. Greene

International Journal of Nuclear Security

Ready access to abundant electricity is a key enabler of modern life. During the past decade the vulnerability of Critical Infrastructure sectors in the U.S. to a variety of natural hazards and man-made threats has become increasingly apparent. The electrical infrastructure (the “Grid”) is the foundation for all other critical civil infrastructures upon which our society depends. Therefore, protection of the Grid is an energy security, homeland security, and national security issue of highest importance. Geomagnetic disturbances (GMD) induced by solar coronal mass ejections (CMEs), electromagnetic pulse (EMP) attacks, and cyber attacks are three events having the potential to ...


Dividing And Conquering Meshes Within The Nist Fire Dynamics Simulator (Fds) On Multicore Computing Systems, Donald Charles Collins Dec 2015

Dividing And Conquering Meshes Within The Nist Fire Dynamics Simulator (Fds) On Multicore Computing Systems, Donald Charles Collins

Masters Theses

The National Institute for Standards and Technology (NIST) Fire Dynamics Simulator (FDS) provides a computational fluid dynamics model of a fire, which can be visualized by using NIST Smokeview (SMV). Users must create a configuration file (*.fds) that describes the environment and other characteristics of the fire scene so that the FDS software can produce the output file (*.smv) needed for visualization.The processing can be computationally intensive, often taking between several minutes and several hours to complete. In many cases, a user will create a file that is not optimized for a multicore computing system. By dividing meshes within ...


Fault Diagnosis And Failure Prognostics Of Lithium-Ion Battery Based On Least Squares Support Vector Machine And Memory Particle Filter Framework, Mohammed Ali Lskaafi Dec 2015

Fault Diagnosis And Failure Prognostics Of Lithium-Ion Battery Based On Least Squares Support Vector Machine And Memory Particle Filter Framework, Mohammed Ali Lskaafi

Doctoral Dissertations

123456A novel data driven approach is developed for fault diagnosis and remaining useful life (RUL) prognostics for lithium-ion batteries using Least Square Support Vector Machine (LS-SVM) and Memory-Particle Filter (M-PF). Unlike traditional data-driven models for capacity fault diagnosis and failure prognosis, which require multidimensional physical characteristics, the proposed algorithm uses only two variables: Energy Efficiency (EE), and Work Temperature. The aim of this novel framework is to improve the accuracy of incipient and abrupt faults diagnosis and failure prognosis. First, the LSSVM is used to generate residual signal based on capacity fade trends of the Li-ion batteries. Second, adaptive threshold ...


Modelling Supercomputer Maintenance Interrupts: Maintenance Policy Recommendations, Jagadish Cherukuri Aug 2015

Modelling Supercomputer Maintenance Interrupts: Maintenance Policy Recommendations, Jagadish Cherukuri

Masters Theses

A supercomputer is a repairable system with large number of compute nodes interconnected to work in harmony to achieve superior computational performance. Reliability of such a complex system depends on an effective maintenance strategy that involves both emergency and preventive maintenance. This thesis analyzes the maintenance records of four supercomputers operational at The National Institute of Computational Science located at Oak Ridge National Laboratory. We propose to use the generalized proportional intensities model (GPIM) to model the maintenance interrupts as it can capture both the reliability parameters and maintenance parameters and allows the inclusion of both emergency and preventive maintenance ...


Requirements For A Computer Code System For The Development And Maintenance Of Target Sets, Christopher Chwasz Aug 2015

Requirements For A Computer Code System For The Development And Maintenance Of Target Sets, Christopher Chwasz

Masters Theses

In the field of commercial nuclear reactor security, the concept of target sets has matured since its invention in the late 1980s and early 1990s to the codification of target set regulations by the United States Nuclear Regulatory Commission in 2009 and publishing of official guidance in 2010. Target sets have evolved into a complex and useful tool to develop and test a protective strategy. By their definition, target sets are the “minimum combination of equipment or operator actions which, if all are prevented from performing their intended safety function or prevented from being accomplished, would likely result in significant ...


Developing An Optimal Model For Infant Home Visitation, Isaac Atuahene Aug 2015

Developing An Optimal Model For Infant Home Visitation, Isaac Atuahene

Doctoral Dissertations

The United States, Great Britain, Denmark, Canada and many other countries have accepted home visitation (HV) as a promising strategy for interventions for infants after births and for their mothers. Prior HV studies have focused on theoretical foundations, evaluations of programs, cost/benefit analysis and cost estimation by using hospital/payer/insurance data to prove its effectiveness and high cost. As governments and private organizations continue to fund HVs, it is an opportune time to develop and formulate operations research (OR) models of HV coverage, quality and cost so they might be used in program implementation as done for adult ...