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A Real-Time Visualization Of An/Pss-14 Audio Alert Signals For Land Mine Detection Validation, Nitin Kolekar 2010 Missouri University of Science and Technology

A Real-Time Visualization Of An/Pss-14 Audio Alert Signals For Land Mine Detection Validation, Nitin Kolekar

Masters Theses

"The central idea of the current research is visualization of audio alerts from AN/PSS-14. A visualization device connected to the arm of PSS-14 will show real-time display of MD and GPR Audio Alert signals from PSS-14. This visualization device displays both amplitude-time and spectral frequency-time formats of the signals. The latter format achieves visual separation of combined, simultaneous, MD and GPR alerts. The joint occurrence of MD and GPR signals in a specific time window confirms the presence of landmine. This window is defined by the time of occurrence of MD peak and time of occurrence GPR diffraction from ...


The Study Of A Model For Via Transition And The Multi-Layer Via Transition Tool Gui Design, Ketan Shringarpure 2010 Missouri University of Science and Technology

The Study Of A Model For Via Transition And The Multi-Layer Via Transition Tool Gui Design, Ketan Shringarpure

Masters Theses

"One of the many challenges faced by engineers working with the present design scenario is to estimate the extent to which a signal, with significant high frequency content, is affected when it is routed on a printed circuit board. The printed circuit board routing will include the transition through the geometries like micro-strip or strip-line transmission lines, via transitions, and irregularities or asymmetries in the aforementioned geometries. One of these discontinuities, the via transition, results in the interaction of the signal on the via and the cavity (plane-pair) through which it passes. The via transition modeling will help characterize a ...


Doubly Fed Induction Generator With Integrated Energy Storage System For Smoothening Of Output Power, Nishant Swaraj Chouhan 2010 Missouri University of Science and Technology

Doubly Fed Induction Generator With Integrated Energy Storage System For Smoothening Of Output Power, Nishant Swaraj Chouhan

Masters Theses

"Wind energy is one of the fastest growing renewable energies in the world today. However, integration of wind power into the power system network is still confronting many challenges. One of the main challenges is the suppression of wind power fluctuations. This thesis focuses on integration of wind power with energy storage to overcome the integration challenges. The first part of this thesis investigates the suitability of energy storage systems for transmission, distribution and wind farm applications. A review on the available energy storage systems is performed considering several criteria. Efforts are made to investigate solutions that meet all the ...


Modeling The Practical Performance Of Switched-Capacitor Converters And A Method For Automating State-Space Model Generation, Jordan M. Henry 2010 Missouri University of Science and Technology

Modeling The Practical Performance Of Switched-Capacitor Converters And A Method For Automating State-Space Model Generation, Jordan M. Henry

Masters Theses

"A new modeling technique and a method for automating the modeling process are introduced for analyzing complex switched-capacitor (SC) converters. The model uses conventional circuit analysis methods to derive state-space models of each switching state. Steady-state performance is derived and expressed as an equivalent resistance. Whereas previous techniques have provided either the detailed performance of a simple SC converter or the limiting performance of a complex SC converter, this new model is flexible enough to provide detailed performance for any practical converter. Nonuniform component choices, asymmetric duty cycles, and other deviations from an ideal converter can be readily included. Dynamics ...


Determining The R Values For 12 Inch Deep Z-Purlins And Girts With Through-Fastened Panels Under Suction Loading, Kaye Dee Wibbenmeyer 2010 Missouri University of Science and Technology

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 ...


High Temperature Tolerant Optical Fiber Inline Microsensors By Laser Fabrication, Tao Wei 2010 Missouri University of Science and Technology

High Temperature Tolerant Optical Fiber Inline Microsensors By Laser Fabrication, Tao Wei

Doctoral Dissertations

"Fiber sensors are particularly attractive for harsh environment defined by high temperature, high pressure, corrosive/erosive, and strong electromagnetic interference, where conventional electronic sensors do not have a chance to survive. However, the key issue has been the robustness of the sensor probe (not the fiber itself) mostly due to the problems stemmed from the traditional assembly based approaches used to construct fiber optic sensors. For example, at high temperatures (e.g., above 500°C), the thermal expansion coefficient mismatch between different composited parts has a high chance to lead to sensors' malfunction by breaking the sensor as a result ...


Interface Polarization Coupling In Piezoelectric-Semiconductor Ferroelectric Heterostructures, Venkata M. Voora, Tino Hofmann, M. Brandt, M. Lorenz, M. Grundmann, N. Ashkenov, H. Schmidt, Natale J. Ianno, Mathias Schubert 2010 University of Nebraska - Lincoln

Interface Polarization Coupling In Piezoelectric-Semiconductor Ferroelectric Heterostructures, Venkata M. Voora, Tino Hofmann, M. Brandt, M. Lorenz, M. Grundmann, N. Ashkenov, H. Schmidt, Natale J. Ianno, Mathias Schubert

Faculty Publications from the Department of Electrical and Computer Engineering

We present a dielectric continuum model approach for studying the electrical polarization properties of interface polarization coupled BaTiO3, BaTiO3-ZnO, and ZnO-BaTiO3-ZnO thin-film structures consisting of several hundred nanometer thick layers. Our model augments the effects of electric field driven switchable polarization and depletion layer formation with spontaneous interface polarization coupling. Wurtzite-structure (piezoelectric) n-type ZnO and perovskite-structure (ferroelectric) highly insulating BaTiO3 layers were prepared and investigated. The coupling between the nonswitchable spontaneous polarization of ZnO and the electrically switchable spontaneous polarization of BaTiO3 causes strong asymmetric polarization hysteresis behavior. The n-type ZnO reveals hysteresis-dependent ...


Variable-Wavelength Frequency-Domain Terahertz Ellipsometry, Tino Hofmann, C. M. Herzinger, A. Boosalis, T. E. Tiwald, John A. Woollam, Mathias Schubert 2010 University of Nebraska - Lincoln

Variable-Wavelength Frequency-Domain Terahertz Ellipsometry, Tino Hofmann, C. M. Herzinger, A. Boosalis, T. E. Tiwald, John A. Woollam, Mathias Schubert

Faculty Publications from the Department of Electrical and Computer Engineering

We report an experimental setup for wavelength-tunable frequency-domain ellipsometric measurements in the terahertz spectral range from 0.2 to 1.5 THz employing a desktop-based backward wave oscillator source. The instrument allows for variable angles of incidence between 30° and 90° and operates in a polarizer-sample-rotating analyzer scheme. The backward wave oscillator source has a tunable base frequency of 107–177 GHz and is augmented with a set of Schottky diode frequency multipliers in order to extend the spectral range to 1.5 THz. We use an odd-bounce image rotation system in combination with a wire grid polarizer to prepare ...


Microbial Reduction Of Uranium Under Iron- And Sulfate-Reducing Conditions: Effect Of Amended Goethite On Microbial Community Composition And Dynamics, H.S. Moon, L. McGuinness, Ravi K. Kukkadapu, A.D. Peacock, John Komlos, L.J. Kerkhof, P.E. Long, Peter R. Jaffe 2010 Princeton University

Microbial Reduction Of Uranium Under Iron- And Sulfate-Reducing Conditions: Effect Of Amended Goethite On Microbial Community Composition And Dynamics, H.S. Moon, L. Mcguinness, Ravi K. Kukkadapu, A.D. Peacock, John Komlos, L.J. Kerkhof, P.E. Long, Peter R. Jaffe

US Department of Energy Publications

There is a growing need for a better understanding of the biogeochemical dynamics involved in microbial U(VI) reduction due to an increasing interest in using biostimulation via electron donor addition as a means to remediate uranium contaminated sites. U (VI) reduction has been observed to be maximized during iron-reducing conditions and to decrease upon commencement of sulfate-reducing conditions. There are many unknowns regarding the impact of iron/sulfate biogeochemistry on U(VI) reduction. This includes Fe(III) availability as well as the microbial community changes, including the activity of iron-reducers during the uranium biostimulation period even after sulfate reduction ...


Protein Adsorption On And Swelling Of Polyelectrolyte Brushes: A Simultaneous Ellipsometry-Quartz Crystal Microbalance Study, Eva Bittrich, Keith B. Rodenhausen Jr., Klaus-Jochen Eichhorn, Tino Hofmann, Mathias Schubert, Manfred Stamm, Petra Uhlmann 2010 Leibniz Institute of Polymer Research Dresden

Protein Adsorption On And Swelling Of Polyelectrolyte Brushes: A Simultaneous Ellipsometry-Quartz Crystal Microbalance Study, Eva Bittrich, Keith B. Rodenhausen Jr., Klaus-Jochen Eichhorn, Tino Hofmann, Mathias Schubert, Manfred Stamm, Petra Uhlmann

Faculty Publications from the Department of Electrical and Computer Engineering

With a coupled spectroscopic ellipsometry-quartz crystal microbalance with dissipation (QCM-D) experimental setup, quantitative information can be obtained about the amount of buffer components (water molecules and ions) coupled to a poly(acrylic acid) (PAA) brush surface in swelling and protein adsorption processes. PAA Guiselin brushes with more than one anchoring point per single polymer chain were prepared. For the swollen brushes a high amount of buffer was found to be coupled to the brush-solution interface in addition to the content of buffer inside the brush layer. Upon adsorption of bovine serum albumin the further incorporation of buffer molecules into the ...


The Use Of Plug-In Hybrid Electric Vehicles For Peak Shaving, Benjamin Andrew Maples 2010 University of Colorado at Boulder

The Use Of Plug-In Hybrid Electric Vehicles For Peak Shaving, Benjamin Andrew Maples

Mechanical Engineering Graduate Theses & Dissertations

This thesis entitled The Use of Plug-In Hybrid Electric Vehicles For Peak Shaving by Benjamin Maples, submitted to the department of Mechanical Engineering in partial fulfillment of the degree of Master of Science, performed under the supervision of Professor Frank Kreith, is a feasibility analysis of the capabilities of PHEV's for peak shaving. The analysis focuses on energy availability of the PHEV fleet as well as the potential financial benefit to the vehicle owner by analyzing different charging scenarios and circuitry. The energy availability is heavily dependent on the location and availability of charging stations. The potential consumer profit ...


Biaxial Mechanical Characterization And Microstructure-Driven Modeling Of Elastic Pulmonary Artery Walls Of Large Mammals Under Hypertensive Conditions, Philip Hsien-Lan Kao 2010 University of Colorado at Boulder

Biaxial Mechanical Characterization And Microstructure-Driven Modeling Of Elastic Pulmonary Artery Walls Of Large Mammals Under Hypertensive Conditions, Philip Hsien-Lan Kao

Mechanical Engineering Graduate Theses & Dissertations

Pulmonary Hypertension (PH) is a disease of the pulmonary vasculature which causes right heart failure. It is known that PH causes significant remodeling of the pulmonary arterial vasculature, but the effects of this remodeling are not well-understood. In addition, there is a dearth of research in large mammals for PH. Modeling of the arteries is also important in the simulation of deformation due to blood flow. Current models either do not reflect the microstructure, or are too complex for clinical use. This work presents mechanical characterization and analysis of the artery wall, in addition to a constitutive model driven by ...


Galvanic Porous Silicon: Processing And Characterization For Nanoenergetics, Collin R. Becker 2010 University of Colorado at Boulder

Galvanic Porous Silicon: Processing And Characterization For Nanoenergetics, Collin R. Becker

Mechanical Engineering Graduate Theses & Dissertations

Porous silicon (PS) is a silicon (Si) based material composed of pores with diameters ranging from several nanometers to several micrometers. Typically PS is formed by electrochemically etching a Si wafer in a hydrofluoric acid (HF) based electrolyte. This route requires a custom built etch cell and a power supply and is difficult to integrate with the batch processing techniques of conventional Microsystems fabrication. In the first part of this work, a galvanic etching approach is used to fabricate PS in which neither a power supply nor custom etch cell are required. Galvanic etching methods are developed to fabricate thick ...


Atomic Layer Deposition Enabled Interconnect And Packaging Technologies For As-Grown Nanowire Devices, Jen-Hau Cheng 2010 University of Colorado at Boulder

Atomic Layer Deposition Enabled Interconnect And Packaging Technologies For As-Grown Nanowire Devices, Jen-Hau Cheng

Mechanical Engineering Graduate Theses & Dissertations

Nanowires (NWs) have attracted considerable interests in many applications due to their small size, extremely high surface-to-volume ratio, and superior material properties. They are promising material candidates as fundamental building blocks for future electronic, optoelectronic, energy, sensor, and biomedical applications. The majority of research activities have focused on the synthesis of NWs. With the advent of high-performance NWs, interconnect and packaging of NWs are becoming increasingly important for device applications. Vertical NW array devices, compared with horizontal NW configurations, are of great importance for achieving ultra-high integration density at the device level without the need of additional assembly and rearrangement ...


Cmos Compatible Thin-Film Ald Tungsten Nanoelectromechanical Devices, Bradley Darren Davidson 2010 University of Colorado at Boulder

Cmos Compatible Thin-Film Ald Tungsten Nanoelectromechanical Devices, Bradley Darren Davidson

Mechanical Engineering Graduate Theses & Dissertations

This research focuses on the development of a novel, low-temperature, CMOS compatible, atomic-layer-deposition (ALD) enabled NEMS fabrication process for the development of ALD Tungsten (WALD) NEMS devices. The devices are intended for use in CMOS/NEMS hybrid systems, and NEMS based micro-processors/controllers capable of reliable operation in harsh environments not accessible to standard CMOS technologies. The majority of NEMS switches/devices to date have been based on carbon-nano-tube (CNT) designs. The devices consume little power during actuation, and as expected, have demonstrated actuation voltages much smaller than MEMS switches. Unfortunately, NEMS CNT switches are not typically CMOS integrable due ...


Nanomaterial Characterization Using Actuated Microelectromechanical Testing Stages, Joseph James Brown 2010 University of Colorado at Boulder

Nanomaterial Characterization Using Actuated Microelectromechanical Testing Stages, Joseph James Brown

Mechanical Engineering Graduate Theses & Dissertations

In this work, microfabricated mechanical systems have been created in a variety of forms and operated to perform nanomaterials characterization tests. A simplified integrated test system was developed and used to collect data from a range of materials including gallium nitride nanowires. A new force estimation approach was developed which enables estimation of the forces provided by electrothermal microelectromechanical (MEMS) actuators, and with knowledge of a material specimen cross-section area, an estimation of the engineering stress within the nanomaterial specimen.

In an expanded design, a MEMS micromanipulator probe interfaced with a removable specimen holder, also known as a test coupon ...


An Ambient Pressure Absorption Heat Pump Using Microporous Membranes: Design, Modeling, And Experimental Investigation, Jason David Woods 2010 National Renewable Energy Laboraratory

An Ambient Pressure Absorption Heat Pump Using Microporous Membranes: Design, Modeling, And Experimental Investigation, Jason David Woods

Mechanical Engineering Graduate Theses & Dissertations

A membrane absorption heat pump uses absorbent (a salt solution) and refrigerant (water) flows separated by a membrane to create a temperature difference, or temperature lift, used for heating or cooling. Compared to conventional absorption heat pumps, an ambient-pressure membrane heat pump is built from simpler, more compact, and potentially less expensive components. Storing the absorbent in an unpressurized tank offers unique options for thermal energy storage for solar heating and cooling of buildings and potential applications in long-distance thermal energy transport.

The contributions of this thesis can be summarized as: (1) design characterization of this novel process, focusing on ...


A Monolithic Spiral Coil Acoustic Transduction Sensor For Chemical And Biological Analytes, Donald F. McCann 2010 The University of Maine

A Monolithic Spiral Coil Acoustic Transduction Sensor For Chemical And Biological Analytes, Donald F. Mccann

Electronic Theses and Dissertations

Acoustic wave sensor platforms typically consist of piezoelectric materials in which bulk or surface acoustic waves are excited by metallic transducers deposited on the sensing surface of the platform. This type of transduction has limitations. In particular the transducer may limit the type of sensing film that can be used or analyte that can be measured and limit the frequency of operation of the sensor. In this work a novel method of exciting high frequency bulk acoustic waves in piezoelectric sensor platforms has been explored. This technique consists of applying time varying electromagnetic fields to the sensor platform using an ...


Finite Element Analysis Of A Nose Gear During Landing, Thoai D. Nguyen 2010 University of North Florida

Finite Element Analysis Of A Nose Gear During Landing, Thoai D. Nguyen

UNF Theses and Dissertations

Nose gear failure is a high concern in the aviation industries. According to the Federal Aviation Administration reports, 55% of aircraft failures occur during takeoff and landing while 45% of failures occur during flight. The objective of this thesis is to determine the stress behavior and the displacement of a nose gear of an aircraft during landing using structural finite element analysis. The nose gear was first modeled using computer-aided design software and then imported into finite element software. The external forces were determined analytically and the interactions between components were carefully modeled using contact analysis. The tire was modeled ...


Development Of A Multi-Material Stereolithography System, Ho-Chan Kim, Jae-Won Choi, Ryan B. Wicker 2010 University of Akron, main campus

Development Of A Multi-Material Stereolithography System, Ho-Chan Kim, Jae-Won Choi, Ryan B. Wicker

Mechanical Engineering Faculty Research

Researchers continue to explore possibilities for expanding additive manufacturing (AM) technologies into direct product manufacturing. One limitation is in the materials available for use in AM that can meet the needs of end-use applications. Stereolithography (SL) is an AM technology well known for its precision and high quality surface finish capabilities. SL builds parts by selectively crosslinking or solidifying photo-curable liquid resins, and the resin industry has been continuously developing new resins with improved performance characteristics. This paper introduces a unique SL machine that can fabricate parts out of multiple SL materials. The technology is based on using multiple vats ...


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