Search results | J. Murrey Atkins Library

Title: A Semi-Quantitative Schlieren High-Speed Flow Diagnostic: Analysis of High-Pressure-Ratio, Overexpanded Planar Flow in Rocket Nozzles
Author: Thorsett-Hill, Karen
Date Created: 2012
Subjects--Topical: Mechanical engineering
Description: This work introduces a semi-quantitative schlieren (SQS) method which is used to qualitatively and quantitatively analyze complex, unsteady, compressible flows in a small, planar convergent-divergent nozzle. A basic schlieren system is used to ima...

Title: Analysis of failure time data with missing and informative auxiliary covariates.
Author: Ghosh, Lipika
Date Created: 2011
Subjects--Topical: Statistics, Mathematics, Biometry
Description: In this dissertation we use Cox's regression model to failure time data with continuous informative auxiliary variables in the presence of a validation subsample. The work is motivated by a common problem of missing or mismeasured covariates in su...

Title: Constitutive Modeling and Dynamic Impact Analysis of Bighorn Sheep Horn
Author: Li, Zheng
Date Created: 2022
Subjects--Topical: Mechanical engineering
Description: Bighorn sheep (Ovis canadensis) is known for its giant spiral horns that can sustain impact loading at a speed up to 5.5 m/s during ramming without causing severe damage or head concussion. The bighorn sheep horn is composed of a keratin-based bio...

Title: EVALUATING THE POTENTIAL USE OF CROWDSOURCED BICYCLE DATA FOR CYCLING ACTIVITIES AND SAFETY ANALYSIS
Author: Lin, Zijing
Date Created: 2020
Subjects--Topical: Transportation
Description: Cycling, as a healthier and greener travel mode, has been encouraged for short-distance trips by city planners and policymakers. Since cycling provides an efficient way to improve public health, alleviate traffic congestion, and reduce energy cons...

Title: Engineering characterization of waste derived geopolymer cement concrete for structural applications
Author: Tempest, Brett
Date Created: 2010
Subjects--Topical: Civil engineering, Sustainability
Description: Geopolymer cements provide an alternative to the Portland cement used to manufacture structural concrete. The material commonly used to produce geopolymers is fly ash, which is found in the waste stream of power generation facilities. Therefore, r...

Title: Finite Element Modeling and Simulations of Tractor-Trailer Impacts on Highway Median Barriers
Author: Gutowski, Matthew
Date Created: 2017
Subjects--Topical: Mechanical engineering
Description: Roadside safety hardware systems play a vital role in reducing both the number and severity of multi-vehicular collisions by preventing errant vehicles from traversing through an open median into oncoming traffic. The safety hardware used to preve...

Title: Finite element modeling and simulation of occupant responses in highway crashes
Author: Li, Ning
Date Created: 2014
Subjects--Topical: Mechanical engineering, Mechanics
Description: Roadside barrier systems play an important role in reducing the number of fatalities and the severity of injuries in highway crashes. After decades of work by researchers and engineers, roadside barriers have been improved and are generally effect...

Title: HYDRODYNAMIC SIMULATIONS OF EJECTA PRODUCTION FROM SHOCKED METALLIC SURFACES
Author: Karkhanis, Varad
Date Created: 2017
Subjects--Topical: Mechanical engineering, Mechanics, Aerospace engineering
Description: The phenomenon of mass ejection into vacuum from a shocked metallic free surfaces can have a deleterious effect on the implosion phase of the Inertial Confinement Fusion (ICF) process. Often, the ejecta take the form of a cloud of particles that a...

Title: Impact of Connected and Autonomous Vehicles on Mobility of Highway Systems
Author: Liu, Pengfei
Date Created: 2020
Subjects--Topical: Transportation, Automated vehicles
Description: Connected and autonomous vehicle (CAV) technologies are known as an effective way to improve safety and mobility of the transportation system. As a combination technology of connected vehicle and autonomous vehicle, CAVs share real time traffic da...

Title: Impacts of connected and autonomous vehicles on deep reinforcement learning controlled intersection systems
Author: Song, Li
Date Created: 2022
Subjects--Topical: Transportation
Description: Connected and autonomous vehicle (CAV) technologies could significantly change the car-following behaviors and affect the performance of the intersection systems. As it is expected to have a long transition time during which human driven vehicles ...

Title: Multiscale modeling of the properties of two-dimensional materials
Author: Wang, Xiaonan
Date Created: 2017
Subjects--Topical: Mechanical engineering
Description: The main objective of this dissertation is to study the thermal and mechanicalproperties of two dimensional materials. For this purpose, we use and combine atomiclevel simulations with continuum level simulations. In this dissertation, moleculardy...

Title: NUMERICAL EVALUATION OF RETROFIT DESIGNS OF CABLE MEDIAN BARRIERS USING RECLAIMED TIRES
Author: Badar, Amey
Date Created: 2017
Subjects--Topical: Mechanical engineering
Description: This thesis presents a research attempt at finding out a viable retrofit system design for cable median barriers using reclaimed tires. Finite element analysis was used to conduct simulations in order to evaluate the performance of retrofit barrie...

Title: Optimal variable speed limit control for mixed traffic flows in a connected and autonomous vehicle environment
Author: Yu, Miao
Date Created: 2018
Subjects--Topical: Civil engineering
Description: Traffic demand grows rapidly over the past decades around the world, which leads to severe traffic congestion problems. Congestion has numerous negative effects, such as wasting time of drivers and passengers, increasing delays, decreasing travel ...

Title: PERFORMANCE EVALUATION OF A TWO-BAR BRIDGE RAIL FOR COMPLIANCE WITH MASH TL-3 CONDITIONS USING FINITE ELEMENT ANALYSIS
Author: Fatoki, Joshua
Date Created: 2020
Subjects--Topical: Mechanical engineering
Description: Roadside barriers are important safety devices installed on highways to mitigate the severity of injuries caused by crashes of errant vehicles. The two-bar metal bridge rail is a commonly used roadside barrier in North Carolina and is recognized f...

Title: PERFORMANCE EVALUATION OF W-BEAM GUARDRAILS ON SLOPED MEDIANS USING NONLINEAR FINITE ELEMENT SIMULATIONS
Author: Baker, Ryan
Date Created: 2014
Subjects--Topical: Transportation--Planning
Description: This thesis presents the research using finite element (FE) modeling and simulations to evaluate the performance of single-faced and double-faced W-beam guardrails for different heights under MASH Test Level 3 (TL-3) impact conditions. The modelin...

Title: RAPID AND DYNAMIC LOAD TESTING OF INSTRUMENTED PZ27 STEEL SHEET PILES
Author: Rice, Corey
Date Created: 2020
Subjects--Topical: Civil engineering
Description: Pile foundations are typically used for structures underlain by weaker soils in order to increase the soil resistance and, subsequently, the axial capacity. In bridge abutments, sheet piles are typically used as facing elements for soil retention ...

Title: STRUCTURAL IDENTIFICATION OF A FULL-SCALE TIED ARCH BRIDGE SPAN USING GENETIC ALGORITHMS
Author: Salas Zamudio, Neal
Date Created: 2016
Subjects--Topical: Civil engineering
Description: Fostered by advancements in computational capabilities and the development of low-cost structural health monitoring systems, structural identification has emerged as a promising experimental technique offering contributions to several applications...

Title: STUDY OF HYBRID STRATEGIES FOR MULTI-OBJECTIVE OPTIMIZATION USING GRADIENT BASED METHODS AND EVOLUTIONARY ALGORITHMS
Author: Paez Bautista, Diego
Date Created: 2013
Subjects--Topical: Mechanical engineering, Mathematics
Description: Most of the optimization problems encountered in engineering have conflicting objectives. In order to solve these problems, genetic algorithms (GAs) and gradient-based methods are widely used. GAs are relatively easy to implement, because these al...

Title: Structural Identification and Vibration-Based Damage Detection Using Interval Arithmetic and Contractor Programming
Author: Kernicky, Timothy
Date Created: 2018
Subjects--Topical: Civil engineering
Description: Structural identification continues to gain increased attention as an applied technique for structural health monitoring and condition assessment. However, methods for structural identification through finite element model updating that have been ...

Title: THE USE OF MACHINE LEARNING METHOD FOR MODELING AND ANALYZING PEDESTRIAN CRASH DATA AND COMPARISONS WITH TRADITIONAL DISCRETE CHOICE METHODS
Author: Li, Yang
Date Created: 2021
Subjects--Topical: Transportation
Description: As one of the most vulnerable entity within the transportation system, pedestrians might face more dangers and sustain severer injuries in the traffic crashes than others. The safety of pedestrians is particularly critical within the context of co...