Engineering Commons^™

Analysis Of Access-To-Space Missions Utilizing On-Board Energy Management And Entropic Analysis, Tyler Winter

Masters Theses

"The overall objective of this study is the thermodynamically consistent quantification of second-law and performance losses for vehicle configurations implemented or suggested for access-to-space missions and the development of the relationships between the mission entropy generation and overall mission performance. The detailed theory which allows thermodynamically rigorous loss accounting (entropy generation and direct relationship to vehicle performance) is developed and discussed for aerospace vehicles. A full vehicle trajectory code utilizing simplified models for multi-stage rockets and air-breathing propulsion systems is developed and validated specifically for use as a testbed for second law-based theory and concepts. Results are shown in which …

Femtosecond Laser Micro-Structuring Of Silicon Wafer In Water Confinement, Songping Wu

Masters Theses

"This thesis investigates the use of femtosecond laser induced surface morphology on silicon wafer surface in water confinement. Unlike irradiation of silicon surfaces in the air, there are no laser induced periodic structures, but irregular roughness is formed when the silicon wafer is ablated under water. Interestingly, a particular parameter combination enables a smooth surface, which can improve the surface quality of micro-machining products. This thesis first investigates the single ablation and multi-pulse ablation processes in order to study the effects of laser parameters on ablation morphology, as well as the basic physics and mechanism of the laser-material interaction process …

Estimation Of Sound Transmission Class And Impact Insulation Class Rating For Steel Framed Assemblies, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Uncertainty Analysis And Sensitivity Analysis For Multidisciplinary Systems Design, Jia Guo

Doctoral Dissertations

"The objective of this research is to quantify the impact of both aleatory and epistemic uncertainties on performances of multidisciplinary systems. Aleatory uncertainty comes from the inherent uncertain nature and epistemic uncertainty comes from the lack of knowledge. Although intensive research has been conducted on aleatory uncertainty, few studies on epistemic uncertainty have been reported. In this work, the two types of uncertainty are analyzed. Aleatory uncertainty is modeled by probability distributions while epistemic uncertainty is modeled by intervals. Probabilistic analysis (PA) and interval analysis (IA) are integrated to capture the effect of the two types of uncertainty. The First …

Geological Sequestration Of Carbon Dioxide By Hydrous Carbonate Formation In Steelmaking Slag, C. Hank Rawlins

Doctoral Dissertations

"The formation of carbonate solids from the alkaline earth oxide phases in steelmaking slag was investigated in dry and aqueous conditions as a vehicle for carbon dioxide sequestration. The goal of this research was to determine the process conditions that would increase the kinetics of the carbonate formation process under hydrous conditions, enabling direct removal of carbon dioxide from steelmaking offgas"--Abstract, page iv.

Imaging In Karst Terrain Using Electrical Resistivity Tomography, Iana Muchaidze

Masters Theses

"The Missouri Department of Transportation (MoDOT) plans to construct a new intersection between highway 60 and highway 65 to alleviate traffic congestion during peak flow periods. This construction site, which is referred to as the Route 60/65 study site in this thesis, is located on the southeastern side of Springfield, Greene County, Missouri. Bedrock in the study area (Burlington-Keokuk Limestone) is characterized by karstic features such as loosing streams, underground caves, and sinkholes. Prior to the commencement of construction, MoDOT conducted a study of the subsurface conditions in the Route 60/65 study site. The main objective was to identify features, …

Application Of Multi-Modal Fusion Techniques For Corrosion Detection And Characterization In Aging Aircraft Components, Soumya De

Masters Theses

"The United States Air Force (USAF) recently estimated that corrosion maintenance costs exceed $800M per year. Given this, it is desirable to reduce the amount of "find it-fix it" corrosion maintenance activities. One method is to introduce a damage tolerance approach for corrosion detection. In order for this to become a reality, a comprehensive snapshot of corrosion present must be generated.

This thesis presents a data fusion process to perform uni- and multi-modal nondestructive testing and evaluation of corrosion under paint and in lap joints for volumetric characterization. The process for analyzing a given structure includes: 1) the acquisition of …

Forecasting Model For Air Taxi, Commercial Airline, And Automobile Demand In The United States, Hojong Baik, Antonio A. Trani, Nicolas Hinze, Howard Swingle, Senanu Ashiabor, Anand Seshadri

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

A nationwide model predicts the annual county-to-county person roundtrips for air taxi, commercial airline, and automobile at 1-year intervals through 2030. the transportation systems analysis model (TSAM) uses the four-step transportation systems modeling process to calculate trip generation, trip distribution, and mode choice for each county origin-destination pair. Network assignment is formulated for commercial airline and air taxi demand. TSAM classifies trip rates by trip purpose, household income group, and type of metropolitan statistical area from which the round-trip started. a graphical user interface with geographic information systems capability is included in the model. Potential applications of the model are …

A Laboratory Study Of Struvite Precipitation For Phosphorus Removal From Concentrated Animal Feeding Operation Wastewater, Sushmita Dhakal

Masters Theses

"Struvite precipitation occurs spontaneously in many wastewater treatment facilities as a nuisance. However, struvite precipitation is now being studied as a method to concurrently treat high phosphorus wastewaters and generate a valuable product. Many factors influence the precipitation of struvite such as component -ion molar ratios, pH, aeration, solubility, solids and mixing energy. In the present work, struvite precipitation in the actual swine wastewater was studied by strategically controlling aeration, pH, and mixing"--Abstract, page iv.

A Hybrid Sensor Network For Watershed Monitoring, John R. Koch

Masters Theses

"This thesis discusses the Hydrological Hybrid Communication Sensor Network (HHCSN), which is designed for in situ measurement of various hydrological properties of a watershed. HHCSN is comprised of a network of sensor strings, each of which connects up to 100 sensing nodes on a communication line as long as 100 m. Each node includes sensors that measure soil attributes of interest, as well as a microcontroller with basic communication and processing capabilities. A relay point at the surface compresses data from the nodes and wirelessly transmits it to a base station that serves as a gateway to the outside world. …

Individual-Based Artificial Ecosystems For Design And Optimization, Shivakar Vulli

Masters Theses

"Individual-based modeling has gained popularity over the last decade, mainly due to the paradigm's proven ability to address a variety of problems seen in many disciplines, including modeling complex systems from bottom-up, providing relationship between component level and system level parameters, and discovering the emergence of system-level behaviors from simple component level interactions. Availability of computational power to run simulation models with thousands to millions of agents is another driving force in the widespread adoption of individual-based modeling. This thesis proposes an individual-based modeling approach for solving engineering design and optimization problems using artificial ecosystems"--Abstract, page iii.

Evaluation Of Su8 And Ruthenium Oxide Materials For Microfluidic Devices, Margaret Theresa Audrain

Masters Theses

"This thesis investigates two materials, SU8 photoresist and RuO₂, for possible incorporation into a self-calibrating microfluidic biosensor. The negative, epoxy based photoresist SU8 has been widely used in the fabrication of micro-electro-mechanical systems (MEMS) devices. This is due to its many desirable features that make it a suitable material for a wide variety of MEMS applications. The effects cross-linking (exposure dose) and bonding time have on bond strength and plasma modification of the SU8 surface were investigated as well as the bond strength of etched SU8. It was shown that adhesive bonding was an effective method of bonding, with bond …

Development Of Ballistic Limit Equations For Dual-Wall Spacecraft Shielding: A Concise History And Suggestions For Future Development, William P. Schonberg

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

All earth-orbiting spacecraft are susceptible to impacts by orbital debris particles, which can occur at extremely high speeds and can damage flight- and mission-critical systems. The traditional damage mitigating shield design for this threat consists of a “bumper” that is placed at a relatively small distance away from the main “inner wall” of the spacecraft. The performance of a hypervelocity impact shield is typically characterized by its ballistic limit equation, which is typically drawn as a line of demarcation between regions of rear-wall perforation and no perforation; when graphically represented, it is often referred to as a ballistic limit curve. …

Formulating Hedging Strategies For Financial Risk Mitigation In Competitive U.S. Electricity Markets, Karthik Viswanathan

Masters Theses

"The challenges currently facing participants in the competitive electricity markets are unique and staggering: unprecedented price volatility, fluctuations in the demand, a lack of historical market data on which to test the new modeling approaches, increased competition and continuously changing regulatory structure...Electricity plant owners and purchasers of electricity may benefit from various techniques to manage price volatility. For electricity, however, no futures market is actively traded. The electricity forward market in NYMEX is in its nascent stage and is low in liquidity. Producers and purchasers of electricity may find cross-hedging electricity with natural gas futures contracts to be effective in …

Experimental Validation Of An Integrated Frp And Visco-Elastic Hardening, Damping, And Wave-Modulating System For Blast Resistance Enhancement Of Rc Columns, Brian Henry Wood

Masters Theses

"In today's society, terrorist attacks and accidental explosions pose a major threat to critical infrastructure. Vulnerable to blast loading, structures must be rehabilitated to ensure structural stability and protect human life. The goal of this study is to develop and validate a sandwich composite technology for column retrofitting. The new technology consists of an inner fiber reinforced polymer (FRP) sheet, an outer FRP sheet, and a visco-elastic (VE) layer sandwiched between the two FRP sheets. The inner FRP sheet is wrapped around an existing column for confinement, while the outer FRP sheet is for anchoring of the VE layer into …

Discussion And Analysis Of Missile Igc Design, Michael W. Dancer, S. N. Balakrishnan, Ernest J. Ohlmeyer

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Missile intercept systems used in the next generation missile defense system will require extremely accurate performance of all component systems. Such systems will need to guarantee successful intercept of highly maneuvering targets. as a result, such interceptor systems require much greater performance in its guidance, control, and estimation subsystems. in order to develop systems that meet the required accuracies, integrated guidance and control (IGC) systems are currently being studied. These IGC architectures infuse the guidance and control systems into a single framework thereby promoting natural synergy among the missile subsystems. Previous work in this area has relied on missile body-Based …

Nonlinear H(Infinity) Missile Longitudinal Autopilot Design With Theta-D Method, Ming Xin, S. N. Balakrishnan

Mechanical and Aerospace Engineering Faculty Research & Creative Works

In this paper, a new nonlinear H 1 control technique, called μ¡D H 1 method, is employed to design a missile longitudinal autopilot. The μ ¡D H 1 design has the same structure as that of linear H 1 , except that the two Riccati equations that are part of the solution process are state dependent. The μ ¡D technique yields suboptimal solutions to nonlinear optimal control problems in the sense that it provides an approximate solution to the Hamilton-Jacobi-Bellman (HJB) equation. It is also shown that this method can be used to provide an approximate closed-form solution to the …

Characterization And Glass Formation Of Jsc-1 Lunar And Martian Soil Simulants, C. S. Ray, Sabhayu Sen, Signo Tadeu Dos Reis

Materials Science and Engineering Faculty Research & Creative Works

The space exploration mission of NASA requires human and robotic presence for long duration beyond the low earth orbit (LEO), especially on Moon and Mars. Developing a human habitat or colony on these planets would require a diverse range of materials, whose applications would range from structural foundations, (human) life support, (electric) power generation to components for scientific instrumentations. A reasonable and cost-effective approach for fabricating the materials needed for establishing a self-sufficient human outpost would be to primarily use local (in situ) resources on these planets. Since ancient times, glass and ceramics have been playing a vital role on …

Progress In Effect Of Jominy End Quench On The Microstructure And Mechanical Properties Of Cast Aluminum Alloys, Qingcai Liu, C. Lu, Joseph William Newkirk

Materials Science and Engineering Faculty Research & Creative Works

In this review, the current knowledge related to the relationship between the heat treatment process and the microstructure and mechanical properties of A356 aluminum alloys are summarized. The review also examines the use of the Jominy end quench (JEQ) specimen and its application to the examination of the effects of quench rate and subsequent processing. Using the design of experimental methods combined with the Jominy end quench technique, desired changes in microstructure and mechanical properties of alloys can be obtained. So, the experimental technique of the Jominy end quench was concerned in this work.

Anomalous Magnetic Ordering In Prba₂Cu₄O₈ And Cmba₂Cu₃O₇, H. A. Blackstead, M. P. Smylie, William B. Yelon, Qingsheng Cai, Mehmet Kahveci

Physics Faculty Research & Creative Works

A review of temperature-dependent magnetization data for nonsuperconducting PrBa2Cu4O8 and CmBa2Cu3O7 suggests that the failure of each to superconduct is related to the presence of Pr and Cm on their respective Ba sites. This defect is manifested, in each case, by short c-axis lattice parameters and anomalous high-temperature magnetic ordering which has been incorrectly attributed to ordering of the entire magnetic sublattice. Instead, it is shown that the anomalous high-temperature ordering as seen in the magnetization data is consistent with the ordering of magnetic ions substituted on the Ba site.

Reactivity Control Schemes For Fast Spectrum Space Nuclear Reactors, Aaron E. Craft, Jeffrey C. King

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Several different reactivity control schemes are considered for future space nuclear reactor power systems. Each of these control schemes uses a combination of boron carbide absorbers and/or beryllium oxide reflectors to achieve sufficient reactivity swing to keep the reactor subcritical during launch and to provide sufficient excess reactivity to operate the reactor over its expected 7-15 year lifetime. The size and shape of the control system directly impacts the size and mass of the space reactor's reflector and shadow shield, leading to a tradeoff between reactivity swing and total system mass. This paper presents a trade study of drum, shutter, …

Phantom For Evaluating Accuracy Of Image Registration Software, B. Y. Choe, H. S. Jin, R. H. Juh, Hyoung-Koo Lee, J. Y. Song, T. S. Suh

Nuclear Engineering and Radiation Science Faculty Research & Creative Works

Provided is a phantom for evaluating the accuracy of image registration software based on a result of matching tomograms of a predetermined position of the phantom, taken using two or more imaging apparatuses. Accordingly, it is possible to more efficiently evaluate the accuracy of the image registration software by comparing the tomograms with one another using a three-dimensional analysis. In addition, it is possible to facilitate the comparison of the tomograms with one another by installing a plurality of indicating bars in the phantom so that their cross sections can appear on each of the tomograms.

A Coarse-Grain Molecular Dynamics Study Of The Nanotribological Properties Of Nanoparticle Solutions, Ramesh Chembeti

Masters Theses

"In this study, solutions of alkanethiol-capped nanoparticles in alkane are examined using molecular dynamics simulations for their nanotribological potential based on the hypothesis that fluid molecules of very different sizes may interrupt each other's layering tendency to result in less layered or non-layered configurations and provide better lubrication for nanodevices. An effective nanoparticle-nanoparticle pair potential based on previous atomistic approach is used and the temperature and parallel pressure are controlled in place of chemical potential for defining thermodynamic state. When compressed, the confined nanoparticle-containing alkane films generate reduced oscillations in perpendicular forces and smoother expansion in lateral dimensions, indicating lesser …

Sorting Automated Concept Generator Results Based On Manufacture And Assembly Concerns, Kerry Ryan Poppa

Masters Theses

"Early in the design process, it is desirable to produce a large number of potential solutions. Completely exploring a problem's solution space is an unreasonable expectation for an unaided designer or design team. Computational tools have emerged to help designers more fully explore possible solutions. These automated concept generators use knowledge from existing designs and the desired functionality of the new product to suggest solutions. Existing automated concept generation methods produce many candidate solutions, but produce unmanageably large sets of solutions. Techniques are needed to organize the set of concepts into smaller groups, more easily parsed by the human designer. …

Application Of Artificial Neural Networks And Colored Petri Nets On Earthquake Resilient Water Distribution Systems, Nandini Kavanal Balakrishnan

Masters Theses

"Water distribution systems are important lifelines and a critical and complex infrastructure of a country. The performance of this system during unexpected rare events is important as it is one of the lifelines that people directly depend on and other factors indirectly impact the economy of a nation. In this thesis a couple of methods that can be used to predict damage and simulate the restoration process of a water distribution system are presented. Contributing to the effort of applying computational tools to infrastructure systems, Artificial Neural Network (ANN) is used to predict the rate of damage in the pipe …

Autothermal Non-Catalytic Reformation Of Jet Fuel In A Supercritical Water Medium, Jason W. Picou

Masters Theses

"The non-catalytic reformation of jet fuel using supercritical water was studied in a specially designed 0.4-L Haynes Alloy 230 tubular reactor. Experiments were performed at a constant pressure of 24.1 MPa, a temperature of 770°C, and at a constant water-to fuel ratio of fifteen-to-one by mass with various space times and oxygen flow rates. The experiments were conducted with and without air flow so as to examine the effects of the concurrent partial oxidation on the overall reformation process. The reactor effluent gas consisted of hydrogen, nitrogen, carbon dioxide, carbon monoxide, methane and ethane. Increasing space time increases the extent …

Aflp Fingerprint Analysis Of Hybrid Salamanders In The Missouri Caverns Section Of Onondaga Cave, Maria Louise Potter

Masters Theses

"Two species and one subspecies of salamander in the genus Eurycea, two species of Plethodon and one species of Typhlotriton (recently considered to be Eurycea) salamander currently reside in an area of Onondaga Cave known as the Missouri Caverns section. Due to the presence of two known interbreeding subspecies of salamanders, Eurycea Longicauda (Long-tailed salamander) and Eurycea longicauda melanopleura (Dark-sided salamander), the possibility may exist for interbreeding of one or all of these taxa. Specifically, it is hypothesized that the two species of Eurycea longicauda may interbreed with Eurycea lucifuga (Cave salamander). through visual assessment and phenotypic analysis, …

Synthesis Of Iron Oxide Nanoparticles In A Counterflow Diffusion Flame Reactor, Hector Enrique Ruiz

Masters Theses

"A Counterflow Diffusion Flame (CDF) reactor was used to produce iron oxide nanoparticles. The experimental work was performed to study synthesis conditions and characterize the iron oxide nanoparticles. The parameters studied are those that control the flame structure, namely, gas flow rates and vacuum; other parameters include the precursor volume flow rate, and the relative location and temperature of the collecting probe inside the flame. Hexagonal nanoparticles were the most commonly observed shape. Hexagonal-shaped nanoparticles are mainly formed under stoichiometric conditions and with a high temperature profile in the flame. Cubic nanoparticles were also observed. The main parameter for the …

Wireless Mote-Based In-Process Diagnostics Using Hand-Held Tools In Network Enabled Manufacturing Environments, Reghu Anguswamy

Masters Theses

"When complex manufacturing systems are considered, post process inspection can be a very time consuming and costly. In addition, no inspection data is typically collected unless a major problem is encountered. Real-time monitoring of the manufacturing processes and verification of its product quality are two important factors to reduce the manufacturing lead time and to ensure safety and quality.

In this thesis, a diagnostics and root-cause analysis scheme with a single channel wireless routing protocol for real-time monitoring of process quality of pull-type fastening operations is first presented. The overall architecture has been implemented on a Huck45 pull-type tool, which …

Behavior Of Full-Scale Rc T-Beams Strengthened In Shear With Externally Bonded Frp Sheets, Antonio Brancaccio

Masters Theses

"Shear deficiencies in many bridges may be considered even more critical than flexural deficiencies since shear failures occur without advance warning and are more catastrophic. Deficiencies in shear can be due to insufficient shear reinforcement, use of outdated design codes, a reduction in the steel area due to corrosion, or an increase in the service load due to change of occupancy for the structure.

In recent years, many research studies have investigated the shear behavior of reinforced concrete (RC) beams strengthened with fiber-reinforced polymer (FRP) composites, however, most of them were conducted on small-scale specimens. Thus, analytical models and design …