Engineering Commons^™

Ab-10-019: Human Performance And Perception-Based Evaluations Of Indoor Noise Criteria For Rating Mechanical System Noise With Time-Varying Fluctuations (1322-Rp), Lily M. Wang, Cathleen C. Novak

Durham School of Architectural Engineering and Construction: Faculty Publications

The goal of this study was to investigate the effects of noise from building mechanical systems with time-varying fluctuations on human task performance and perception, and to determine how well current indoor noise rating methods account for this performance and perception. Six different noise conditions with varying degrees of time-varying fluctuations, many focused in the low frequency rumble region, were reproduced in an office-like setting. Thirty participants were asked to complete typing, grammatical reasoning, and math tasks plus subjective questionnaires, while being exposed for approximately one hour to each noise condition. Results show that the noise conditions with higher sound …

Phase Equilibria In Iron Phosphate System, Liying Zhang

Doctoral Dissertations

"The main objectives of this research were to synthesize iron phosphate compounds, study phase equilibria in the iron phosphate system, focusing on the glass forming area, and investigate glass formability and properties based on the liquidus regions. Twelve iron phosphate compounds were successfully prepared and studied in terms of liquidus temperature or decomposition behavior. The liquidus surface of the Fe₃PO₇- Fe(PO₃)₃ system was re-determined and found to be significantly different from that originally presented by Wentrup in 1935. Eutectic points exist at 58.0 mole% Fe₂O₃ (1070⁰C), 42.7 mole% Fe₂O₃ (925°C), and 37.0 mole% Fe₂O₃ (907°C). The latter two eutectic points …

Solid Oxide Fuel Cell Electrode Characterization And Improvement For Fuel Flexibility And Supplemental Power Production, Isaiah D. Kellogg

Doctoral Dissertations

"Solid oxide fuel cells (SOFC) were fabricated and the electrodes tested for their individual catalytic effectiveness in various fuels by exposing each electrode to mixed gas while the opposite electrode was exposed to its respective pure gas. Mixed hydrogen and oxygen gas was successfully utilized as fuel in a single chamber SOFC (SC-SOFC). The conditions at which the porous nickel-yttria-stabilized zirconia (Ni-YSZ) cermet anode performed well did not significantly overlap the conditions at which the La₀.₈Sr₀.₂Fe₀.₈Co₀.₂ oxide (LSCF) cathode performed well, but there was significant catalytic activity at both electrodes which increased the open circuit voltage (OCV) beyond that predicted …

Experimental Study On Thermal Treatment Of Used Printed Wiring Boards (Pwbs), Xiangjun Zuo

Masters Theses

The availability of cheaper and better electronic products as a result of the rapid innovation in technology in past decades has driven the production of e-waste forward. Printed wiring board (PWB) is a component made of one or more layers of insulating material with electrical conductors. The existing processes of recycling PWBs use pyrometallurgical or hydrometallurgical methods, which generate atmospheric pollution. Green recycling has obvious benefits to decrease the amount of PWBs. Green recycling includes two features, 1) little or zero pollution of toxic gases and heavy metals, and 2) efficient (quick and economical) recycling.

The aim of this work …

Maskless Additive Manufacturing Of Micro Structures By Laser Sintering Of Nanoparticles, Vivekram Ramanathan

Masters Theses

"The focus of this study was to investigate an alternate microfabrication process of sintering nanoparticles using a patterned laser light to generate two dimensional (2D) and three dimensional (3D) geometries. With trends of producing electronic and medical devices using cheaper and faster technologies, a new procedure was developed to deposit and bond miniature patterns of silver nanoparticles onto silicon substrates.

The process consists of spraying silver nanoparticles onto the substrate while a patterned or modulated laser beam is focused onto the sprayed nanoparticles. These nanoparticles exposed under the modulated laser light undergo partial melting or sintering and adhere to the …

Decentralized Coordinated Ilc System Design And Transient Growth Control Using Iteration-Varying Filter, Qing Liu

Masters Theses

"In automation control area, with the increasing demand in task complexity and high control precision, coordination between systems is required. There are mainly two types of coordinated systems, decentralized and centralized. This thesis is focused on a large array of coordinated systems, and the decentralized structure is preferred. To achieve high control precision in a coordinated system, many existing approaches may work, and in the system performing the repeating process, Iterative Learning Control (ILC) is a useful approach. Therefore, in this thesis, a decentralized coordinated ILC system is proposed and analyzed. The proposed control system is especially useful in coordinating …

Detection Of Explosive Threats By Using Embedded Wireless Sensor Based Networks, Jake Daniel Hertenstein

Masters Theses

"This thesis focuses on the development of novel schemes for the detection of unintended electromagnetic emissions (UEE) from passive radio frequency (RF) receivers and chemical and biological (CB) agents for the purpose of locating explosive threats (ET) to improve survivability for equipment and personnel in the surrounding environment. The methods and architectures used in this work were developed for use with wireless sensor networks (WSNs). While previous work has shown that highly sensitive equipment is capable of long-range detection of UEE the intention of this work is to develop a network of small, low cost smart sensor nodes (SSNs) capable …

Efficient Modular Arithmetic Units For Low Power Cryptographic Applications, Rajashekhar Reddy Modugu

Masters Theses

"The demand for high security in energy constrained devices such as mobiles and PDAs is growing rapidly. This leads to the need for efficient design of cryptographic algorithms which offer data integrity, authentication, non-repudiation and confidentiality of the encrypted data and communication channels. The public key cryptography is an ideal choice for data integrity, authentication and non-repudiation whereas the private key cryptography ensures the confidentiality of the data transmitted. The latter has an extremely high encryption speed but it has certain limitations which make it unsuitable for use in certain applications. Numerous public key cryptographic algorithms are available in the …

Integration And Characterization Of An Electrical Storage System For A Hydrogen Fuel Cell Plug-In Hybrid Electric Vehicle, Edward Alexei Anculle Arauco

Masters Theses

"Hydrogen fuel cell hybrid vehicles are an advance technology that promises to solve the energy crisis in transportation and green houses emissions. Even more, Plug-in or extended range vehicles can add diversity in energy sources. Extended range vehicles have the capability to extract energy from the grid and hence reduce the cost of operation of the vehicle. EcoCAR: the NeXt Challenge is a Noth [sic] American competition with seventeen schools participating across North America. Missouri S&T is developing a Fuel Cell Plug-in Hybrid electric vehicle which has a large lithium-ion battery able to store 16 kWh. The fuel cell powertrain …

Synergy Between Biology And Systems Resilience, Ashik Chandra

Masters Theses

"Resilient systems have the ability to endure and successfully recover from disturbances by identifying problems and mobilizing the available resources to cope with the disturbance. Resiliency lets a system recover from disruptions, variations, and a degradation of expected working conditions. Biological systems are resilient. Immune systems are highly adaptive and scalable, with the ability to cope with multiple data sources, fuse information together, makes decisions, have multiple interacting agents, operate in a distributed manner over a multiple scales, and have a memory structure to facilitate learning. Ecosystems are resilient since they have the capacity to absorb disturbance and are able …

Analysis Of The Theta-D Filter As Applied To Hit-To-Kill Interceptors And Satellite Orbit Determination, Michael W. Dancer

Masters Theses

"When designing feedback control systems, there is often a need for estimation methods that provide system information that is not readily available via sensors placed within the system. In many cases a sensor that measures a particular system state either does not exist or is prohibitively expensive. In addition, all realistic systems contain some degree of nonlinearity. This thesis focuses on two such cases: missile guidance with bearings-only measurements and GPS satellite orbit determination. In each case, a new nonlinear filter, the [theta]-D method, is used and evaluated for its performance in providing the necessary estimation. To aid the filter …

Internet-Accessible Hot Cell With Gamma Spectroscopy At The Missouri University Of Science And Technology Research Nuclear Reactor, Edwin Grant

Masters Theses

A dual-chambered internet-accessible heavily shielded facility with pneumatic access to the University of Missouri Science and Technology (Missouri S&T) 200 kW Research Nuclear Reactor (MSTR) core has been built and is currently under low level irradiation testing. The facility allows distance users doing collaborative work with Missouri S&T researchers to manipulate and analyze neutron irradiated samples remotely. The system consists of two shielded compartments, one for multiple sample storage (up to 11 samples), and the other for isolated radiation measurements and spectroscopy. The second chamber has multiple detector ports, graded shielding, and has the capability to support gamma spectroscopy using …

Energy-Efficient Task-Scheduling And Networking Protocols For Secure Wireless Networks, Sandeep Kolli

Masters Theses

"The performance of wireless networks is dependent on a number of factors including the available energy, energy-efficiency, data processing delay, transmission delay, routing decisions, security overhead, etc. Traditionally, due to limited resources, nodes were tasked with only collecting measurements and sending them to a base station or central unit for processing. With increased capabilities of microprocessors the data processing is pushed more toward network and its more capable nodes. This thesis focuses to virtualize the processing resources of the entire network and dynamically distribute processing steps along the routing path while optimizing performance. Additionally, a new multi-key encryption (MKE) scheme …

The Properties And Structure Of Tin Phosphate Glasses Modified With Other Oxides, Jong Wook (Austin) Lim

Masters Theses

"The main objective of this research was to evaluate the properties and structures of glasses from the stannous (SnO) phosphate system for possible use in low temperature optical applications. Glasses in the binary xSnO-(100-x)P₂O₅ system (50 ≤ x ≤ 70) were prepared and their thermal and optical properties were evaluated. Differences in glass transition temperatures (T_g) measured here and reported in the literature were explained by differences in the residual water content in the glasses, as determined by infrared spectroscopy. In general, increasing the SnO content of the binary glasses increased the refractive index and the glass transition …

Validation Of Driving Simulator And Driver Perception Of Vehicle Mounted Attenuator Markings In Work Zones, Durga Raj Mathur

Masters Theses

"This research work sought to validate the driving simulator at Missouri University of Science and Technology and to evaluate the vehicle mounted attenuator (VMA) markings for various times of day. For comprehensive validation of the driving simulator, a framework is proposed which is demonstrated using a fixed-base driving simulator. Objective and subjective evaluations were conducted, and validation of the driving simulator was performed at specific locations and along the highway. Field data were collected for a partial lane closure using a global positioning system (GPS) along the work zone and supplemented with video recordings of traffic data at specific locations …

Management Of A University Satellite Program With Focus On A Refrigerant-Based Propulsion System, Shawn W. Miller

Masters Theses

"The Missouri University of Science and Technology Satellite (M-SAT) design team has established a satellite program to develop a pair of satellites to perform an autonomous formation flight mission. The resulting configuration was assembled for the Air Force Research Lab University Nanosat Program. This document, written by the Program Manager and former member of the Propulsion subsystem, is a description of the management process used by the team to develop a satellite configuration. Included in the document is a discussion of team organization, techniques for managing a program, and lessons learned during the 2007 to 2008 timeframe. The managing techniques …

Quantification Of Channel Performance And Development And Characterization Of Small Magnetic Field Probes, Surbhi Mittal

Masters Theses

"This thesis presents a new approach to quantifying channel performance using a transmitter waveform and dispersion penalty (TWDP) with frequency domain S-parameter data. Initially TWDP was defined to characterize the performance of a transmitter in optical links. More recently its use has been extended to include the quantification of channel performance, especially in high-speed copper links. This project focused mainly on channel characterization. Instead of using the time-domain oscilloscope measurements involved in the original approach, it proposes a new method that relies on frequency-domain S-parameter data obtained either from measurements or simulations. It included a parametric study of TWDP with …

Control And Design Considerations In Electric-Drive Vehicles, Shweta Neglur

Masters Theses

"Electric-drive vehicles have been identified as one of the promising technologies of the future. Electric-drive vehicles including fuel cell, hybrid electric, and plug-in hybrid electric vehicles have the potential to improve the fuel economy and reduce gas emissions when compared to conventional vehicles. One of the important challenges in the advancement of the electric-drive vehicles is to develop a control strategy which meets the power requirements of the vehicles. The control strategy is an algorithm designed to command the battery and the internal combustion engine of the vehicle for specific power demands. In this thesis, load follower and thermostat control …

Optimization Of Parameters And Study Of Kinetics In Lactulose Production By Lactose Isomerization Using Strong Basic Anion Exchange Resin, Arvind Nanduri

Masters Theses

"In this work, an experimental design was employed to investigate the effects of different operating conditions on the isomerization of lactose to lactulose by using strong basic anion exchange resin (AMBERLITE-IRA 402). Temperature, resin/lactose mass ratio and pH were considered to be the three factors affecting the conversion of lactose. Box-Behnken design was then used to optimize the operating conditions for maximum response and also to study the various interaction and main effects of the factors. The analysis of variance (ANOVA) of the experimental data showed a high correlation coefficient R² (0.99) and a low root mean square error (2.84) …

Modeling And Analysis Of High-Speed Sources And Serial Links For Signal Integrity, Siming Pan

Masters Theses

"As the computer and electronics industry moves towards higher data rates, signal integrity and electromagnetic interference (EMI) problems always present challenges for designers for high-speed data communication systems. To characterize the entire link path between transmitters and receivers, accurate models for sources, passive link path (such as traces, vias, connectors, etc), and terminations should be built before simulations either in frequency or time domain. Due to the imperfection of model, data corrections are preferred before time-domain simulations to ensure stability. Moreover, data obtained from models should be compared with measurement results to judge the level of agreement for validations. This …

Time-Domain Thru-Reflect-Line (Trl) Calibration Error Assessment And Its Mitigation And Modeling Of Multilayer Printed Circuit Boards (Pcb) With Complex Area Fills, Vysakh Sivarajan

Masters Theses

"Part 1 for this thesis is on the error assessment of a time-domain (t-TRL) calibration technique. Application of the "Thru-Reflect-Line" (TRL) calibration to time-domain measurements of S-parameters (t-TRL) can be used for the characterization of the printed circuit boards (PCBs). However, t-TRL calibrated results still have deviations from the reference frequency-domain vector network analyzer (VNA) calibrated results. There are two main sources of errors in the t-TRL calibration. They are random errors, such as an additive noise and jitter, and systematic errors associated with cables, connectors, and port mismatches. This work addresses these two types of errors by proper selection …

Determining The R Values For 12 Inch Deep Z-Purlins And Girts With Through-Fastened Panels Under Suction Loading, Kaye Dee Wibbenmeyer

Masters Theses

"Designing purlins for roof systems attached to through-fastened panels has been a subject well researched in the past. The current design specification uses a simplified approach to the designing of these members where the fully braced moment capacity of such members is multiplied by a reduction factor, commonly referred to as the R-value. This value represents the point in between the fully braced and fully unbraced member behavior. However, the current AISI Specification, S100, only contains R-values for purlins and girts up to 11.5 inches in depth. Since manufacturers are now rolling sections up to 12 inches deep, two confirmatory …

Corrosion Resistance Of Enamel-Coated Steel Reinforcement For Concrete, Charles Robert Werner

Masters Theses

"Originally developed to enhance the bond between concrete and steel, reactive enamel coatings have shown great promise in protecting steel from corrosive environments. However, the corrosion resistance of the material has not yet been tested beyond 40 days. Moreover, when the material was tested, it was applied to smooth steel pins, not deformed steel bars which are commonly used in reinforced concrete structures. Therefore, this study focused on the corrosion resistance of three different enamel coatings, along with a standard epoxy coating, each of which were applied to both smooth and deformed steel bars and included both short-term and long-term …

Synthesis And Characterization Of Microspheres For Controlled Release, Gurpartap Singh Sandhu

Masters Theses

"Synthetic hydroxyapatite (HAp, (Ca₁₀(PO₄)₆(OH)₂) has always been of interest in medical applications because of its similarities to inorganic bone matrix. It has been used in biomedical applications for bone repair and substitution due to its biocompatibility. However, there are some differences in the stoichiometry, composition, and mechanical properties of human bone as compared to pure HAP. HAp particles have been successfully used as drug delivery carriers which deliver the drug to the affected part of the body and the remaining apatite gets degraded by the physiological processes in the body. In the present work, emphasis was on developing mechanically stronger …

Nonlinear Finite Element Formulation Of The Soil Structure Interaction Through Two Parameter Foundation Model, Taraka Ravi Shankar Mullapudi

Masters Theses

"The response of shallow and raft foundations is having a significant importance due to its complex behavior because of the semi-infinite soil media. Winkler's model is the simplest model to deal with the structure and soil. The Winkler model represents the foundation reaction as proportional to the soil displacement at a particular point, which results in the elasticity of the soil being the only parameter in consideration. But in reality the soil cohesiveness is having a significant contribution in soil structure interaction, and therefore the consideration of coupling effects of Winkler springs need to be accounted. Most of the existing …

Application Of Quality Function Deployment In New Product And Service Development, Anusha Uppalanchi

Masters Theses

"Quality Function Deployment (QFD) is a systematic process to integrate customer requirements into every aspect of the design and delivery of products and services. Understanding the customers wants or needs from a product or service is crucial to the successful design and development of new products and services. QFD is a system that utilizes customer demands to meet client missions by outlining what the customer wants in a service or product. QFD was used in this research to determine customer needs and thus to ensure that customer demands are met. This methodology is demonstrated using two case studies: Hydrogen Fuel …

A Numerical Investigation Of Flowfield Modification In High-Speed Airbreathing Inlets Using Energy Deposition, Matthew Flynn Rohweder

Masters Theses

"Energy deposition in front of dual-mode ram/scramjet engines is numerically investigated utilizing two-dimensional CFD for its potential to modify inlet/isolator flow-fields for engine start/unstart control and for its general potential for generating large-scale flow-field modification in such flows. A simplified (high Mach number) constant-area duct geometry is initially defined in order to test the feasibility of the concept; the results from this initial investigation demonstrates possible beneficial effects of depositing energy upstream of a thermally choked duct in terms of causing massive changes in flow patterns, including the reestablishment of supersonic flow throughout the duct. This study is followed by …

Characterizing Near-Field Circuit Board Radiation Using Crossed Electric And Magnetic Dipole Sources, Weiping He

Masters Theses

"A method to analyze radiated emissions of electronic components/circuits is presented in this thesis. More specifically the purpose of this approach is to determine an equivalent source model to accurately represent the radiated emissions produced by the circuits and components. The proposed equivalent source model, which is able to predict both electric and magnetic fields at various distances from the device under test, consists of an array of both electric and magnetic dipoles. Each source point includes two electric dipoles orientated in x and y directions and two magnetic dipoles in x and y directions"--Abstract, page iii.

Characterization Of The Neutron Flux Spectrum At The Missouri University Of Science And Technology Research Reactor, Zachary Andrew Kulage

Masters Theses

"A new remotely accessible shielded cell is being constructed at the Missouri University of Science and Technology Research Reactor (MSTR). The heavily shielded cell will be able to receive highly irradiated specimens directly from the reactor and will be equipped with radiation-hardened cameras, remote manipulators and gamma spectroscopy. The cell will allow the manipulation and monitoring of highly activated specimens from both a workstation at the MSTR and at remote locations using a Webbased internet interface. The ability to access and control the shielded cell via a remote internet connection will make it useful to a wide variety of users. …

Fabrication Of A Memory Device Using Polyaniline Nanofibers And Gold Nanoparticles, Krunal R. Waghela

Masters Theses

"Fabrication of a memory device using one-step/one-pot synthesis for making a PANI (polyaniline)/Au nanocomposite is reported. Although various devices with horizontal and vertical electrode structures were made, the basic structure used consisted of a PANI/Au thin film sandwiched between two electrodes. The ratio of the current in the OFF state to the current in the ON state was seen to be as high as 5000. These devices showed a bistable behavior, which is typical of memory devices. The PANI/Au nanocomposite thin film was constructed right on the electrode using microfabrication techniques with ultraviolet irradiation. The fabrication techniques discussed in this …