Engineering Commons^™

A Pulse-Based Feature Extractor For Spike Sorting Neural Signals, Christy L. Rogers, John G. Harris, Jose C. Principe, Justin C. Sanchez

Electrical and Computer Engineering Faculty Research & Creative Works

Spike sorting is often required for analyzing neural recordings to isolate the activity of single neurons. Wave shape analysis in the spike sorting procedure provides a means to detect spikes while minimizing the influence of false alarms. As neural recording techniques allow for recording hundreds of electrodes, power is too limited in neural implants for current spike sorting algorithms. Even with spike sorting at the back end where more power is available, the bandwidth is too limited to transmit enough information for current spike sorting techniques. A low-power pulse-based feature extractor presented in the paper is a solution to the …

Wireless, In Vivo Neural Recording Using A Custom Integrated Bioamplifier And The Pico System, David Cheney, Aik Goh, Jie Xu, Karl Gugel, John G. Harris, Justin C. Sanchez, Jose C. Principe

Electrical and Computer Engineering Faculty Research & Creative Works

This paper describes a wireless system for sampling multiple channels of neural activity based on a low-power, custom 80dB-gain integrated bio amplifier, Texas Instrument's MSP430 microprocessors, and Nordic Semiconductor's ultra-low power, high bandwidth RF transmitter/receivers. The system's features are presented as well as results of spike potentials from a live subject. © 2007 IEEE.

Effect Of Hydrofluoric Acid In Oxidizing Acid Mixtures On The Hydroxylation Of Silicon Surface, Sanjukta Guhathakurta, Anuradha Subramanian

Anuradha Subramanian Publications

Silicon (100) wafers, predipped in 1:20 (v/v) HF water, were treated separately with four different acid mixtures, viz., HNO₃, H₂SO₄–H₂O₂, HNO₂–HF, and H₂SO₄–H₂O₂–HF, for different time durations. Subsequent vigorous rinsing with deionized water rendered the wafer surfaces with hydroxyl termination. Synthesized surfaces were characterized by diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS), ellipsometry, contact angle and atomic force microscopy. Surfaces treated with HN0₃ and H₂SO₂–H₂O₂ showed increasing hydrophilicity at room temperature due to …

Blueprint For Iteratively Hardening Power Grids Employing Unified Power Flow Controllers, William M. Siever, Ann K. Miller, Daniel R. Tauritz

Electrical and Computer Engineering Faculty Research & Creative Works

A stable electricity supply is vital for modern society. However, many parts of our power transmission grid are operating near their operational limits. Such stressed systems are vulnerable to cascading failures, where a few small faults can induce a cascade of failures potentially leading to a major blackout The unified power flow controller (UPFC), the most powerful highspeed, semi-conductor based power flow device, can be used as a theoretical model to study how these devices can be used to improve power grid resilience. The blueprint presented here can be used to iteratively identify critical weaknesses in power grids and to …

A Probabilistic Approach To Measuring Robustness In Computing Systems, Behdis Eslamnour, Shoukat Ali

Electrical and Computer Engineering Faculty Research & Creative Works

System builders are becoming increasingly interested in robust design. We believe that a methodology for generating robustness metrics will help the robust design research efforts and, in general, is an important step in the efforts to create robust computing systems. the purpose of the research in this paper is to quantify the robustness of a resource allocation, with the eventual objective of setting a standard that could easily be instantiated for a particular computing system to generate a robustness metric. We present our theoretical foundation for a robustness metric and give its instantiation for a particular system. © 2007 IEEE.

Diagnosis Of Inter-Turn Short Circuit For A Polyphase Induction Motor In Closed-Loop Vector-Controlled Drives, Ahmed Sayed-Ahmed, Gennadi Y. Sizov, Nabeel Demerdash

Electrical and Computer Engineering Faculty Research and Publications

The main objective of this paper is to develop and experimentally verify a new technique to detect an inter-turn short circuit in one phase of a stator winding of an induction motor energized from a vector-controlled drive. This is in order to overcome the fault masking difficulties associated with the concept of depending on the actual magnetic field pendulous oscillation between the conventional voltage and current space vectors with respect to a reference that is unaltered by the compensation action of the drive. This technique is based on the flux pendulous oscillation phenomenon. This flux pendulous oscillation is also described …

The Benefits Of Automatic Data Collection In The Fresh Produce Supply Chain, Ryan Charles Panos, Tali Freed

Industrial and Manufacturing Engineering

The potential for RFID based systems to improve the safety and efficiency of a supply chain with rapidly decaying products and strict health standards is creating pressure to adopt RFID in several agricultural industries. A handful of fresh produce industry leaders currently participate in mandated pilot projects, while the industry as a whole is still intimidated by the perceived cost of RFID. Therefore in this study we attempt to validate the correlation between performance and automated data collection, paving the way to economic justification of investment in data collection technologies, such as barcode and RFID.

The majority of product in …

Presenting Science And Engineering Careers In A Unique And Appealing Way., Nihad E. Daidzic, Vojin R. Nikolic

Aviation Department Publications

An original summer camp activity in the areas of aerospace/aeronautical engineering and aviation has been developed. A pilot version of the program was completed successfully in June 2007 at Minnesota State University, Mankato. The main objective of the program was to increase the awareness and interest among high school students for science and engineering careers. Through a series of short lectures and extensive hands-on demonstrations the attending students have been familiarized with the fundamental concepts and relationships of science and engineering in general, and of aerospace engineering and aviation, in particular. Two major team projects have been completed and tested. …

Integrated Modeling Of Nitrate Contamination Of Groundwater In Agriculture-Dominated Watersheds, M. Almasri, Jagath J. Kaluarachchi

Civil and Environmental Engineering Faculty Publications

This paper presents and implements a framework for modeling the impact of land use practices and protection alternatives on nitrate pollution of groundwater in agricultural watersheds. The framework utilizes the national land cover database (NLCD) of the United State Geological Survey (USGS) grid and a geographic information system (GIS) to account for the spatial distribution of on-ground nitrogen sources and corresponding loadings. The framework employs a soil nitrogen dynamic model to estimate nitrate leaching to groundwater. These estimates were used in developing a groundwater nitrate fate and transport model. The framework considers both point and non-point sources of nitrogen across …

Round-Robin Testing Of A Dewpoint Potentiameter Versus Filter Paper To Determine Total Suction, Thomas M. Petry, Cheng Ping Jiang

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Expansive clays exhibit high potential for volume change when changes in soil moisture occur. It has been estimated that the annual cost of damage to facilities built on expansive clay in the United States exceeds $9 billion. the use of soil suction measurements to predict potential clay volume changes has shown significant promise, yet the currently utilized method to determine soil suction, the filter paper method, has serious drawbacks. First, the test takes approximately 8 days to complete, making it less than practical for broad use by practicing engineers. Second, and more troublesome, the filter paper test is difficult to …

Embedded Centrosymmetric Multilayer Stacks As Complete-Transmission Quarter-Wave And Half-Wave Retarders Under Conditions Of Frustrated Total Internal Reflection, S. R. Perla, R. M.A. Azzam

Electrical Engineering Faculty Publications

A centrosymmetric multilayer stack of two transparent materials, which is embedded in a high-index prism, can function as a complete-transmission quarter-wave or half-wave retarder (QWR or HWR) under conditions of frustrated total internal reflection. The multilayer consists of a high-index center layer sandwiched between two identical low-index films with high-index–low-index bilayers repeated on both sides of the central trilayer, maintaining the symmetry of the entire stack and constituting a QWR ( Δt=90° or 270°) or HWR (Δt=180°) in transmission. A QWR design at wavelengthλ=1.55 μm is presented that employs an 11-layer stack of Si and SiO2 thin films, which is …

Ceas E-News 09.18.2007, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

Job hunting season opens next week at Engineering Opportunity Day

Light Beam Targeting And Positioning System For A Paint Or Coating Removal Blasting System, Richard J. Klein Ii, Christopher A. Lampe

Patents (University of Northern Iowa)

A blasting system for the removal of coatings or paint from an underlying surface uses an optical device to position the blasting nozzle an appropriate stand-off distance from the surface. The blasting media can use a variety of blasting media including abrasives, water, and various specialty blasting media. The preferred optical system is mounted to or integral with the blasting nozzle, and uses a diode laser, a beam splitter and a reflecting mirror to generate a reference beam and a gauge beam. Alternatively, two diode lasers can be used to generate the reference beam and gauge beam respectively. The reference …

A Computational Model Of Culture-Specific Conversational Behavior, Dusan Jan, David Herrera, Bilyana Martinovski, David G. Novick, David Traum

Departmental Papers (CS)

This paper presents a model for simulating cultural differences in the conversational behavior of virtual agents. The model provides parameters for differences in proxemics, gaze and overlap in turn taking. We present a review of literature on these factors and show results of a study where native speakers of North American English, Mexican Spanish and Arabic were asked to rate the realism of the simulations generated based on different cultural parameters with respect to their culture.

National Livestock And Poultry Environmental Learning Center, Richard K. Koelsch, Mark Risse, Joe Harrison, Jill Heemstra

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

This paper describes a new national learning center designed to improve the delivery of science-based information to non-research customers. The vision of the Livestock and Poultry Environmental Learning Center is to provide individuals involved in public policy issues, animal production, and delivery of technical services for confined animal systems with on-demand access to the nation’s best science-based resources that is responsive to priority and emerging environmental issues associated with animal agriculture. This project will test innovative approaches such as a web cast seminar series to connect national experts with those individuals and organizations that influence animal producer decisions on manure …

Association Of Odor Measures With Annoyance: An Odor-Monitoring Field Study, Richard R. Stowell, Christopher G. Henry, Richard K. Koelsch, Dennis D. Schulte

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

Multiple assessments of ambient odor were made by trained individuals in the vicinity of a swine finishing operation in eastern Nebraska during the summers of 2005 and 2006. This paper addresses an analysis of assessor responses in Year 1 of this field study to determine what relationships existed between field odor measurements/ratings and ratings of annoyance potential, and to identify candidate measurement threshold values for odors that are likely to cause an annoyance. The first-year results showed that the likelihood of odor causing annoyance increased as ambient odors became more offensive, more intense, and more concentrated, with r² values …

Software Tool For Integrating Feed Management Into Nutrient Planning, Richard K. Koelsch, Ray Massey, Galen E. Erickson, Virgil R. Bremer

Department of Agricultural and Biological Systems Engineering: Presentations and White Papers

The introduction of ASABE Standard D384.2, Manure Production and Characteristics, has created the opportunity to integrate feed management decisions and animal performance measures into nutrient planning processes. This paper introduces a software tool that integrates estimates of nutrient excretion based on the new standard with estimates of land need, labor and equipment time allocation, and economic cost and benefit for manure application. This tool will be used to evaluate the economic implications for two scenarios using beef cattle examples as a means of illustrating tool application. The first scenario will look at the impact of feeding ethanol co-products on the …

Principles, Functions, And Concepts For Compliant Mechanically Reactive Armor Elements, Cameron S. Andersen

Theses and Dissertations

There exists a great need for armor systems with greater mass efficiencies and ballistic limits. This thesis explores the development of a new field of armor capable of satisfying the increased demand for modern armor: Mechanically Reactive Armor or MRA. More specifically, the thesis focuses on Compliant MRA or CMRA. From the physics governing projectile-armor interactions, principles governing successful design of MRA are identified and presented. These principles or design approaches focus primarily on rejecting, minimizing, or absorbing the incoming projectile's kinetic energy. After identifying these principles, the specific mechanical functions required by the principles are isolated. These functions represent …

Evaluation Of Current Nonlinear Static Procedures For Concrete Buildings Using Recorded Strong-Motion Data, Rakesh K. Goel, Charles Chadwell

Civil and Environmental Engineering

This paper evaluates current Nonlinear Static Procedures (NSPs) specified in the FEMA- 356, ASCE-41, ATC-40, and FEMA-440 documents using strong-motion data from reinforcedconcrete buildings. For this purpose, peak roof (or target node) displacements estimated from the NSPs are compared with the value derived from recorded motions. It is shown that: (1) the NSPs either overestimate or underestimate the peak roof displacement for several of the buildings considered in this investigation; (2) the ASCE-41 Coefficient Method (CM), which is based on recent improvements to the FEMA-356 CM suggested in FEMA-440 document, does not necessarily provide better estimate of roof displacement; and …

Investigation Of Reynolds Stresses In A 3d Idealized Urban Area Using Large Eddy Simulation, Akshay A. Gowardhan, E. R. Pardyjak, Inanc Senocak, M. J. Brown

Mechanical and Biomedical Engineering Faculty Publications and Presentations

High resolution, large eddy simulation (LES) of neutral flow through an array of cubes has been conducted with periodic boundary conditions in lateral and longitudinal directions. In this paper, we first describe the model formulation and validate the simulation by comparing the mean flow and turbulence statistics with wind-tunnel experimental data from a cube array of buildings. The LES model is then used to investigate the physical mechanisms that lead to the low turbulent stresses that have been reported in the lower half of the urban canopy layer. To do this, the urban boundary layer is conceptually broken down into …

Search Techniques For Multi-Objective Optimization Of Mixed Variable Systems Having Stochastic Responses, Jennifer G. Walston

Theses and Dissertations

A research approach is presented for solving stochastic, multi-objective optimization problems. First, the class of mesh adaptive direct search (MADS) algorithms for nonlinearly constrained optimization is extended to mixed variable problems. The resulting algorithm, MV-MADS, is then extended to stochastic problems (MVMADS-RS), via a ranking and selection procedure. Finally, a two-stage method is developed that combines the generalized pattern search/ranking and selection (MGPS-RS) algorithms for single-objective, mixed variable, stochastic problems with a multi-objective approach that makes use of interactive techniques for the specification of aspiration and reservation levels, scalarization functions, and multi-objective ranking and selection. A convergence analysis for the …

Water Savings And Rainwater Harvesting – Pilot Project In Ireland, Sean O'Hogain, Anna Reid, Liam Mccarton, Jenny Pender, Niamh Mcntyre

Conference papers

A pilot project to harvest rainwater was set up in Ireland in 2005 to examine the potential of using rainwater harvesting systems to replace treated mains water, for non-potable uses. The Project has two strands to it. The agricultural application assessed the feasibility of incorporating rainwater supply to supplement/replace mains or other water supplies for farms. The second strand involves rural water supply to domestic dwellings. Here the project installed rainwater harvesting and water conservation devices as part of a pilot project to assess the reduction in domestic demand. This paper will examine the water use recorded on both sites. …

Hybrid Micro-Electro-Mechanical Tunable Filter, Edward M. Ochoa

Theses and Dissertations

While advantages such as good thermal stability and processing-chemical compatibilities exist for common monolithic-integrated micro-electro-mechanically tunable filters (MEM-TF) and MEM-tunable vertical cavity surface emitting lasers (MT-VCSEL), they often require full processing to determine device characteristics. Alternatively, the MEM actuators and the optical parts may be fabricated separately, then subsequently bonded. This "hybrid approach" potentially increases design flexibility. Since hybrid techniques allow integration of heterogeneous material systems, "best of breed" compound optoelectronic devices may be customized to enable materials groups to be optimized for tasks they are best suited. Thus, as a first step toward a hybrid (Al_xGa_{1- …}

Ceas E-News 09.11.2007, College Of Engineering And Applied Sciences

College of Engineering and Applied Sciences News

Dedication of Parkview wind turbine set for Friday, Sept. 14

Method And Apparatus For Blood Flow Measurement Using Millimeter Wave Band, David Nelson

Michigan Tech Patents

A system and method that determines a blood flow rate in an area of a subject. The system includes a transmitter operable to transmit an electrical signal in the range of about 20 GHz to about 300 GHz to the area, a temperature sensor positioned adjacent the area, and a processor operable to determine the blood flow rate in the area based on the rate of change of temperature in the area as a result of the application of the electrical signal on the area and a power density value.

Numerical Simulation Of Vortex Generating Jets In Zero And Adverse Pressure Gradients, Curtis Lynn Memory

Theses and Dissertations

Numerical simulations of particle image velocimetry (PIV) experiments conducted with vortex generating jets (VGJs) on a flat plate, at a Reynolds number based on plate length of 50,000, were performed for three flow conditions using a time-accurate hybrid Navier-Stokes solver. Time-averaged steady blowing of angled jets, subjected to a zero pressure gradient, yielded excellent agreement with the PIV data in terms of vortex formation and strength. Observed flow features include primary and secondary vortices, where the primary vortex eventually dominates the downstream region. A shell wall structure, created by smaller vortical structures surrounding the developing vortices, was also observed. A …

Final Assembly, Testing And Processing Of The Rigidizable Inflatable Get-Away-Special Experiment (Rigex) For Spaceflight Qualification, Jeremy J. Owens

Theses and Dissertations

The purpose of this research is to complete the building, testing, verification, and qualification of the Rigidizable Inflatable Get-Away-Special Experiment (RIGEX) for spaceflight. The process of qualifying a payload for spaceflight is discussed, specifically addressing the issues of operability and survivability verification of a general payload. The spaceflight qualification process is then applied to the RIGEX payload at the Air Force Institute of Technology (AFIT) and at the Johnson Spaceflight Center (JSC) in Houston, TX, capstoning the work of 12 masters students and 3 summer interns that has already gone into the RIGEX project over the last 7 years. The …

H.264 Scalable Video Over Finite-State Markov Chain Wireless Channels, Guogang Hua, Daewon Song, David L. Hench, Chang Wen Chen

Electrical Engineering and Computer Science Faculty Publications

In this paper, a wireless channel is viewed as a heterogeneous network in the time domain, and an adaptive video transmission scheme for H.264 scalable video over wireless channels modeled as a finite-state Markov chain processes is presented. In order to investigate the robustness of adaptive video transmission for H.264 scalable video over wireless channels, statistical channel models can be employed to characterize the error and loss behavior of the video transmission. Among various statistical channel models, a finite-state Markov model has been considered as suitable for both wireless links as Rayleigh fading channels and wireless local area networks as …

Measurement Of 'One Over F Noise' In Infrared Detection Using A Novel Technique, Diana Maestas Jepson

Electrical and Computer Engineering ETDs

It has been shown that, one over f noise' (1/f noise) limits the sensitivity in Mercury Cadmium Telluride (HgCdTe) infrared devices. It is therefore imperative to be able to measure and account for its contribution to the total device noise. In this thesis, the 1/f noise of a HgCdTe device is measured and studied using two measurement techniques. The first technique is the commonly used conventional method of measuring 1/f noise that analyzes 1/f noise in the frequency domain and extracts the 1/f noise contribution from the power spectral densities. The second approach is a novel technique that extracts the …

Nasa - Basics Of Space Flight, Nasa

Robert "Bob" Twiggs STEM Education Collection

NASA website titled "Basics of Space Flight" from September 9, 2007.