Engineering Commons^™

Intellectual Property Management In Health And Agricultural Innovation: A Handbook Of Best Practices, Vol. 2, Anatole Krattiger, Richard T. Mahoney, Lita Nelsen, Jennifer A. Thomson, Alan B. Bennett, Kanikaram Satyanarayana, Gregory D. Graff, Carlos Fernandez, Stanley Kowalski

Law Faculty Scholarship

Prepared by and for policy-makers, leaders of public sector research establishments, technology transfer professionals, licensing executives, and scientists, this online resource offers up-to-date information and strategies for utilizing the power of both intellectual property and the public domain. Emphasis is placed on advancing innovation in health and agriculture, though many of the principles outlined here are broadly applicable across technology fields. Eschewing ideological debates and general proclamations, the authors always keep their eye on the practical side of IP management. The site is based on a comprehensive Handbook and Executive Guide that provide substantive discussions and analysis of the opportunities …

High-Frequency Ultrasound Drug Delivery And Cavitation, Mario Alfonso Diaz

Theses and Dissertations

The viability of a drug delivery system which encapsulates chemotherapeutic drugs (Doxorubicin) in the hydrophobic core of polymeric micelles and triggers release by ultrasound application was investigated at an applied frequency of 500 kHz. The investigation also included elucidating the mechanism of drug release at 70 kHz, a frequency which had previously been shown to induce drug release. A fluorescence detection chamber was used to measure in vitro drug release from both Pluronic and stabilized micelles and a hydrophone was used to monitor bubble activity during the experiments. A threshold for release between 0.35 and 0.40 in mechanical index was …

A Numerical Vortex Approach To Aerodynamic Modeling Of Suav/Vtol Aircraft, Douglas F. Hunsaker

Theses and Dissertations

A combined wing and propeller model is presented as a low-cost approach to preliminary modeling of slipstream effects on a finite wing. The wing aerodynamic model employs a numerical lifting-line method utilizing the 3D vortex lifting law along with known 2D airfoil data to predict the lift distribution across a wing for a prescribed upstream flowfield. The propeller/slipstream model uses blade element theory combined with momentum conservation equations. This model is expected to be of significant importance in the design of tail-sitter vertical take-off and landing (VTOL) aircraft, where the propeller slipstream is the primary source of air flow past …

Spectroscopic Ellipsometer And Polarimeter Systems, John A. Woollam, Blaine D. Johs, Craig M. Herzinger, Ping He, Martin M. Liphardt, Galen L. Pfeiffer

Department of Electrical and Computer Engineering: Faculty Publications

A spectroscopic ellipsometer or polarimeter system having a source of a polychromatic beam of electromagnetic radiation, a polarizer, a stage for supporting a material system, an analyzer, a dispersive optics and a detector system which comprises a multiplicity of detector elements, there being apertures before the stage for supporting a material system, and thereafter, the system being present in an environmental control chamber.

First Flights: 100 Years Of Powered Flight, University Of South Alabama

Aeronautics

Bibliography and photographs of a display of government documents from the University of South Alabama.

Geometrical Modeling Of Fibrous Materials Under Compression, Benoit Maze, Hooman Vahedi Tafreshi, Behnam Pourdeyhimi

Mechanical and Nuclear Engineering Publications

Many fibrous materials such as nonwovens are consolidated via compaction rolls in a so-called calendering process. Hot rolls compress the fiber assembly and cause fiber-to-fiber bonding resulting in a strong yet porous structure. In this paper, we describe an algorithm for generating three dimensional virtual fiberwebs and simulating the geometrical changes that happen to the structure during the calendering process. Fibers are assumed to be continuous filaments with square cross sections lying randomly in the x or y direction. The fibers are assumed to be flexible to allow bending over one another during the compression process. Lateral displacement is not …

Flap Gate, Charles M. Burt

BioResource and Agricultural Engineering

ITRC began to investigate early designs of Flap Gates in 1992. The gates originated in The Netherlands in the 1940s, but no design criteria were available. ITRC developed an Excel design program that uses a combination of theory and coefficients from field results – and has continued to improve the program almost every year. District staff at Turlock ID and Chowchilla WD provided valuable feedback with early models. This report includes information on design, installation, maintenance, water conservation and efficiency, cost, use, and benefits.

ITRC Flap Gates are typically used with a concrete counterweight in situations where the gates are …

The Places We Will Go, Minnesota State University, Mankato

Aeronautics

Bibliography and photographs of a display of government documents from Minnesota State University, Mankato.

Electrical And Computer Engineering Research Report 2007, Department Of Electrical And Computer Engineering, Michigan Technological University

Department of Electrical and Computer Engineering Annual Reports

• About the Department
• Graduates and Research
• NSF CAREER Award Winner
• New Faculty Spotlight
• Research Programs
• Enterprise Team Updates

Hydrologic Monitoring Of An Integrated Low Impact Development (Lid) Underdrained Stormwater Management System , Nancy-Jeanne Bachmann

Dissertations, Master's Theses and Master's Reports - Open

In 2005, Wetland Studies and Solutions, Inc. (WSSI) installed an extensive Low Impact Development (LID) stormwater management system on their new office site in Gainesville, Virginia. The 4-acre site is serviced by a network of LID components: permeable pavements (two proprietary and one gravel type), bioretention cell / rain garden, green roof, vegetated swale, rainwater harvesting and drip irrigation, and slow-release underground detention. The site consists of heavy clay soils, and the LID components are mostly integrated by a series of underdrain pipes. A comprehensive monitoring system has been designed and installed to measure hydrologic performance throughout the LID, underdrained …

Evaluation Of An Existing Steel Post Alternative For The Thrie Beam Bullnose Guardrail System, Robert W. Bielenberg, Ronald K. Faller, John R. Rohde, John D. Reid

Mid-America Transportation Center: Final Reports and Technical Briefs

Recently, the Minnesota Department of Transportation (MnDOT) funded a research project through the Midwest States Regional Pooled Fund to evaluate an existing steel post alternative for the thrie beam bullnose barrier system previously developed at the Midwest Roadside Safety Facility (MwRSF). MnDOT had an interest in the replacement of the wooden breakaway posts used in the current bullnose system with proprietary breakaway steel posts. The research project consisted of evaluation of current breakaway steel post designs, investigation and selection of a candidate post design, and full-scale testing of the bullnose system with a steel post alternative. The full-scale testing was …

Vorticity Dynamics And Sound Generation In Two-Dimensional Fluid Flow, Raymond J. Nagem, Guido Sandri, David Uminsky

Mathematics

An approximate solution to the two-dimensional incompressible fluid equations is constructed by expanding the vorticity field in a series of derivatives of a Gaussian vortex. The expansion is used to analyze the motion of a corotating Gaussian vortex pair, and the spatial rotation frequency of the vortex pair is derived directly from the fluid vorticity equation. The resulting rotation frequency includes the effects of finite vortex core size and viscosity and reduces, in the appropriate limit, to the rotation frequency of the Kirchhoff point vortex theory. The expansion is then used in the low Mach number Lighthill equation to derive …

Baby-Steps Towards Building A Spanglish Language Model, Juan C. Franco, Thamar Solorio

Departmental Technical Reports (CS)

Abstract. Spanglish is the simultaneous use, or alternating of both, traditional Spanish and English within the same conversational event. This interlanguage is commonly used in U.S. populations with large percentages of Spanish speakers. Despite the popularity of this dialect, and the wide spread of automated voice systems, currently there are no spoken dialog applications that can process Spanglish. In this paper we present the first attempt towards creating a Spanglish language model.

Effects Of Subsurface Drainage On Pavement Performance, James Crovetti, Kathleen T. Hall

Transportation Reports with the Wisconsin Department of Transportation

This report evaluates the effects of subsurface drainage features on pavement performance through a program of inspection and testing of the subsurface drainage features present in the Long-Term Pavement Performance (LTPP) SPS-1 and SPS-2 field sections. The report will be of particular interest to engineers in the public and private sectors with responsibility for the design, construction, and rehabilitation of highway pavements.

Hardware Implementation Of Active Disturbance Rejection Control For Vibrating Beam Gyroscope, David Avanesian

ETD Archive

Obtaining the approximation of rotation rate form a Z-Axis MEMS gyroscope is a challenging problem. Currently, most commercially available MEMS gyroscopes are operating in an open-loop for purposes of simplicity and cost reduction. However, MEMS gyroscopes are still fairly expensive and are not robust during operation. The purpose of this research was to develop a high-performance and low-cost MEMS gyroscope using analog Active Disturbance Rejection Control (ADRC) system. By designing and implementing analog ADRC both above requirements were satisfied. Analog ADRC provides the fastest response time possible (because the circuit is analog), eliminates both internal and external disturbances, and increases …

Byzantine Fault Tolerant Coordination For Web Services Atomic Transactions, Honglei Zhang

ETD Archive

This thesis describes a Byzantine fault tolerant coordination framework for Web services atomic transactions. In the framework, all core services, including transaction activation, registration, completion, and distributed commit, are replicated and protected by Byzantine fault tolerance mechanisms. The traditional two-phase commit protocol is extended by a Byzantine fault tolerant version that can tolerate arbitrary faults on the coordinator and the initiator sides, and some types of malicious faults on the participant side. To achieve Byzantine fault tolerance in an efficient manner, and to limit the types of malicious behaviors of the coordinator, a novel decision certificate is introduced. The decision …

Water Quality Modelling In Dublin From Bray To Balbriggan Gdsds/75407/130, Aodh Dowley, Zeinab Bedri

Reports

No abstract provided.

Electron Mobility In Ingan Channel Heterostructure Field Effect Transistor Structures With Different Barriers, J. Xie, J. H. Leach, X. Ni, M. Wu, R. Shimada, Ü. Özgür, Hadis Morkoç

Electrical and Computer Engineering Publications

InGaN possesses higher electron mobility and velocity than GaN, and therefore is expected to lead to relatively better performances for heterostructure field effect transistors (HFETs). However, the reported mobilities for AlGaN∕InGaNHFETs are lower than GaN channel HFETs. To address this issue, we studied the effect of different barriers on the Hall mobility for InGaN channel HFETs grown by metal organic chemical vapor deposition. Unlike the conventional AlGaN barrier, the AlInN barrier can be grown at the same temperature as the InGaN channel layer, alleviating some of the technological roadblocks. Specifically, this avoids possible degradation of the thin InGaN channel during …

Structural And Electrical Properties Of Pb(Zr,Ti)O3 Films Grown By Molecular Beam Epitaxy, N. Izyumskaya, Vitaliy Avrutin, X. Gu, B. Xiao, Serguei A. Chevtchenko, J-G Yoon, Hadis Morkoç, Lin Zhou, David J. Smith

Electrical and Computer Engineering Publications

Single-crystal, single-phase Pb(ZrxTi1−x)O3 films (x=0–0.4) were grown on (001)SrTiO3 and SrTiO3:Nb substrates by molecular beam epitaxy. Layer-by-layer growth of thePb(Zr,Ti)O3 films was achieved by using PbTiO3 buffer layers between the SrTiO3substrates and the Pb(Zr,Ti)O3 films. The layers with low Zr content showed high crystallinity with full width at half maximum of ω -rocking curves as low as 4arcmin , whereas increase in Zr concentration led to pronounced angular broadening. The PbZr0.07Ti0.93O3 filmsexhibited remanent polarization as high as 83μC/cm2 , but local areas suffered from nonuniform leakage current.

Epitaxial Growth Of Zro2 On Gan Templates By Oxide Molecular Beam Epitaxy, Xing Gu, Natalia Izyumskaya, Vitaliy Avrutin, Bo Xiao, Hadis Morkoç

Electrical and Computer Engineering Publications

Molecular beam epitaxial growth of ZrO2 has been achieved on GaN(0001)∕c-Al2O3substrates employing a reactive H2O2 oxygen source. A low temperature buffer followed by in situ annealing and high temperature growth has been employed to attain monoclinic, (100)-oriented ZrO2thin films. The typical full width at half maximum of a 30-nm-thick ZrO2 (100) film rocking curves is 0.4arcdeg and the root-mean-square surface roughness is ∼4Å. ω−2θand pole figure x-ray diffraction patterns confirm the monoclinic structure of ZrO2. Data support an in-plane epitaxial relationship of ZrO2 [010]∥∥GaN[112¯] and ZrO2 [001]∥∥GaN[11¯00]. X-ray diffraction and reflection high-energy electron diffraction analyses reveal in-plane compressive strain, which …

Structural And Electrical Properties Of Pb(Zr,Ti)O3 Grown On (0001) Gan Using A Double Pbtio3∕Pbo Bridge Layer, Bo Xiao, Xing Gu, Natalia Izyumskaya, Vitaliy Avrutin, Jinqiao Xie, Huiyong Liu, Hadis Morkoç

Electrical and Computer Engineering Publications

Pb(Zr0.52Ti0.48)O3 films were deposited by rf magnetron sputtering on silicon-doped GaN(0001)∕c-sapphire with a PbTiO3∕PbO oxide bridge layer grown by molecular beam epitaxy. X-ray diffraction data showed the highly (111)-oriented perovskite phase in lead zirconate titanate(PZT) films with PbTiO3∕PbO bridge layers, compared to the pyrochlore phase grown directly on GaN. The in-plane epitaxial relationships were found from x-ray pole figures to be PZT[112¯]∥∥GaN[11¯00] and PZT[11¯0]∥∥GaN[112¯0]. The polarization-electric field measurements revealed the ferroelectric behavior with remanent polarization of 30–40μC/cm2 and asymmetric hysteresis loops due to the depletion layer formed in GaN under reverse bias which resulted in a high negative coercive electric …

Dielectric Functions And Critical Points Of Pbtio3, Pbzro3, And Pbzr0.57ti0.43o3 Grown On Srtio3 Substrate, T. D. Kang, Hosun Lee, G. Xing, N. Izyumskaya, Vitaliy Avrutin, Bo Xiao, Hadis Morkoç

Electrical and Computer Engineering Publications

Single crystalline PbTiO3, PbZrO3, and PbZr0.57Ti0.43O3 thin films on SrTiO3 (001) substrates were grown by a combination of molecular beam epitaxy and rf sputtering methods. The authors measured the dielectric functions of the thin films using spectroscopic ellipsometry and determined the interband critical point energies using standard critical point model. They compared the critical point energies to the band structure calculations in the literature. The data suggest that anticrossing behavior occurs between Ea and Eb near Zr=0.17. This phenomenon is attributed to a coupling between X1c and X3c bands caused by intrinsic alloy disorder.

Defect Reduction In Gan Epilayers Grown By Metal-Organic Chemical Vapor Deposition With In Situ Sinx Nanonetwork, Jinqiao Xie, Serguei A. Chevtchenko, Ü. Özgür, Hadis Morkoç

Electrical and Computer Engineering Publications

Line and point defect reductions in thin GaN epilayers with single and double in situ SiNxnanonetworks on sapphire substrates grown by metal-organic chemical vapor deposition were studied by deep-level transient spectroscopy(DLTS), augmented by x-ray diffraction(XRD), and low temperature photoluminescence(PL). All samples measured by DLTS in the temperature range from 80to400K exhibited trap A (peak at ∼325K) with an activation energy of 0.55–0.58eV, and trap B (peak at ∼155K) with an activation energy of 0.21–0.28eV. The concentrations of both traps were much lower for layers with SiNx nanonetwork compared to the reference sample. The lowest concentration was achieved for the sample …

High Electron Mobility In Nearly Lattice-Matched Alinn∕Aln∕Gan Heterostructure Field Effect Transistors, Jinqiao Xie, Xianfeng Ni, Mo Wu, Jacob H. Leach, Ü. Özgür, Hadis Morkoç

Electrical and Computer Engineering Publications

High electron mobility was achieved in Al1−xInxN∕AlN∕GaN (x=0.20–0.12)heterostructurefield effect transistors(HFETs) grown by metal-organic chemical vapor deposition. Reduction of In composition from 20% to 12% increased the room temperature equivalent two-dimensional-electron-gas density from 0.90×1013to1.64×1013cm−2 with corresponding electron mobilities of 1600 and 1410cm2/Vs, respectively. The 10Kmobility reached 17600cm2/Vs for the nearly lattice-matched Al0.82In0.18N∕AlN∕GaNheterostructure with a sheet carrier density of 9.6×1012cm−2. For comparison, the AlInN∕GaNheterostructure without the AlN spacer exhibited a high sheet carrier density(2.42×1013cm−2) with low mobility(120cm2/Vs) at room temperature. The high mobility in our samples is in part attributed to ∼1nm AlN spacer which significantly reduces the alloy scattering as well …

Epitaxial Lateral Overgrowth Of (112¯2) Semipolar Gan On (11¯00) M-Plane Sapphire By Metalorganic Chemical Vapor Deposition, X. Ni, Ü. Özgür, A. A. Baski, Hadis Morkoç, Lin Zhou, David J. Smith, C. A. Tran

Electrical and Computer Engineering Publications

The authors report the growth of semipolar (112¯2)GaNfilms on nominally on-axis (101¯0) m-plane sapphire substrates using metal organic chemical vapor deposition. High-resolution x-ray diffraction(XRD) results indicate a preferred (112¯2)GaN orientation. Moreover, epitaxial lateral overgrowth (ELO) of GaN was carried out on the (112¯2) oriented GaN templates. When the ELO stripes were aligned along [112¯0]sapphire, the Ga-polar wings were inclined by 32° with respect to the substrate plane with smooth extended nonpolar a-plane GaN surfaces and polar c-plane GaNgrowth fronts. When compared with the template, the on-axis and off-axis XRD rocking curves indicated significant improvement in the crystalline quality by ELO …

Nanostructuring Induced Enhancement Of Radiation Hardness In Gan Epilayers, V. V. Ursaki, I. M. Tiginyanu, O. Volcuic, V. Popa, V. A. Skuratov, Hadis Morkoç

Electrical and Computer Engineering Publications

The radiation hardness of as-grown and electrochemically nanostructured GaN epilayers against heavy ion irradiation was studied by means of photoluminescence(PL) and resonant Raman scattering (RRS) spectroscopy. A nanostructuring induced enhancement of the GaN radiation hardness by more than one order of magnitude was derived from the PL and RRS analyses. These findings show that electrochemical nanostructuring of GaN layers is a potentially attractive technology for the development of radiation hard devices.

Low Dislocation Densities And Long Carrier Lifetimes In Gan Thin Films Grown On A Sinx Nanonetwork, J. Xie, Ü. Özgür, Y. Fu, X. Ni, Hadis Morkoç, C. K. Inoki, T. S. Kuan, J. V. Foreman, H. O. Everitt

Electrical and Computer Engineering Publications

Significant improvement of structural and optical qualities of GaNthin films on sapphire substrates was achieved by metal organic chemical vapor deposition with in situ SiNxnanonetwork. Transmission electron microscope (TEM) studies revealed that screw- and edge-type dislocations were reduced to 4.4×107 and 1.7×107cm−2, respectively, for a ∼5.5-μm-thick layer. Furthermore, room temperature carrier lifetimes of 2.22 and 2.49ns were measured by time-resolved photoluminescence(TRPL) for samples containing single and double SiNx network layers, respectively, representing a significant improvement over the previous studies. The consistent trends among the TEM,x-ray diffraction, and TRPL measurements suggest that in situ SiNx network reduces line defects effectively as …

Energy Dispersion Relations Of Spin-Split Subbands In A Quantum Wire And Electrostatic Modulation Of Carrier Spin Polarization, Sandipan Pramanik, Supriyo Bandyopadhyay, M. Cahay

Electrical and Computer Engineering Publications

We numerically calculate the energy dispersion relations of the spin-split subbands in a quantum wire subjected to a transverse magnetic field in the presence of Rashba and Dresselhaus spin-orbit interactions. The spin splitting energy at zero wave vector is found to be neither equal to the bare Zeeman splitting nor linear in the magnetic field in any subband. This happens because the expectation value of the spin angular momentum operator varies along the width of the wire, causing a spatial modulation of the spin density. We also show that spin splitting energy is subband dependent and has a complex dependence …

Digital Switch And Femtotesla Magnetic Field Sensor Based On Fano Resonance In A Spin Field Effect Transistor, J. Wan, M. Cahay, S. Bandyopadhyay

Electrical and Computer Engineering Publications

We show that a spin field effect transistor, realized with a semiconductor quantum wire channel sandwiched between half-metallic ferromagnetic contacts, can have Fano resonances in the transmission spectrum. These resonances appear because the ferromagnets are half-metallic, so that the Fermi level can be placed above the majority but below the minority spin band. In that case, the majority spins will be propagating, but the minority spins will be evanescent. At low temperatures, the Fano resonances can be exploited to implement a digital binary switch that can be turned on or off with a very small gate voltage swing of few …

Epitaxial Lateral Overgrowth Of A-Plane Gan By Metalorganic Chemical Vapor Deposition, X. Ni, U. Ozgur, H. Morkoç, Z. Liliental-Weber, H. O. Everitt

Electrical and Computer Engineering Publications

We report on epitaxial lateral overgrowth (ELO) of (112¯0) a-plane GaN by metalorganic chemical vapor deposition. Different growth rates of Ga- and N-polar wings together with wing tilt create a major obstacle for achieving a smooth, fully coalesced surface in ELOa-plane GaN. To address this issue a two-step growth method was employed to provide a large aspect ratio of height to width in the first growth step followed by enhanced lateral growth in the second by controlling the growth temperature. By this method, the average ratio of Ga- to N-polar wing growth rate has been reduced from 4–6 to 1.5–2, …