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Full-Text Articles in Engineering

Trans-Dimensional Geoacoustic Inversion Of Wind-Driven Ambient Noise, Jorge E. Quijano, Stan E. Dosso, Jan Dettmer, Lisa M. Zurk, Martin Siderius Dec 2012

Trans-Dimensional Geoacoustic Inversion Of Wind-Driven Ambient Noise, Jorge E. Quijano, Stan E. Dosso, Jan Dettmer, Lisa M. Zurk, Martin Siderius

Electrical and Computer Engineering Faculty Publications and Presentations

This letter applies trans-dimensional Bayesian geoacoustic inversion to quantify the uncertainty due to model selection when inverting bottom-loss data derived from wind-driven ambient-noise measurements. A partition model is used to represent the seabed, in which the number of layers, their thicknesses, and acoustic parameters are unknowns to be determined from the data. Exploration of the parameter space is implemented using the Metropolis–Hastings algorithm with parallel tempering, whereas jumps between parameterizations are controlled by a reversible-jump Markov chain Monte Carlo algorithm. Sediment uncertainty profiles from inversion of simulated and experimental data are presented.


Experimental Validation Of Phase Using Nomarski Microscopy With An Extended Fried Algorithm, Scott A. Prahl, Amanda Dayton, Kyle Juedes, Erik J. Sánchez, Rafael Paez López, Donald D. Duncan Oct 2012

Experimental Validation Of Phase Using Nomarski Microscopy With An Extended Fried Algorithm, Scott A. Prahl, Amanda Dayton, Kyle Juedes, Erik J. Sánchez, Rafael Paez López, Donald D. Duncan

Electrical and Computer Engineering Faculty Publications and Presentations

Reconstruction of an image (or shape or wavefront) from measurements of the derivatives of the image in two orthogonal directions is a common problem. We demonstrate how a particular reconstructor, commonly referred to as the Fried algorithm, can be used with megapixel derivative images to recover the original image. Large datasets are handled by breaking the derivative images into smaller tiles, applying the Fried algorithm and stitching the tiles back together. The performance of the algorithm is demonstrated using differential interference contrast microscopy on a known test object.


Aspect-Dependent Radiated Noise Analysis Of An Underway Autonomous Underwater Vehicle, John Gebbie, Martin Siderius, John S. Allen Iii Oct 2012

Aspect-Dependent Radiated Noise Analysis Of An Underway Autonomous Underwater Vehicle, John Gebbie, Martin Siderius, John S. Allen Iii

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents an analysis of the acoustic emissions emitted by an underway REMUS-100 autonomous underwater vehicle(AUV) that were obtained near Honolulu Harbor, HI using a fixed, bottom-mounted horizontal line array (HLA). Spectral analysis,beamforming, and cross-correlation facilitate identification of independent sources of noise originating from the AUV. Fusion of navigational records from the AUV with acoustic data from the HLA allows for an aspect-dependent presentation of calculated source levels of the strongest propulsion tone.


Patent Analysis For Smart Grid Development In The U.S, Abrahim Abdulsater, Bahareh Saatchi, Farshad Madani Apr 2012

Patent Analysis For Smart Grid Development In The U.S, Abrahim Abdulsater, Bahareh Saatchi, Farshad Madani

Engineering and Technology Management Student Projects

By increasing demand for energy among nations the rate of fossil fuel consumption is boosting. The raise of fossil fuel consumption has motivated nations to gain some capabilities for the purpose of dealing with some consequences; the more fossil fuel consumption, the higher price for energy, and the higher rate of GHG as well. Recently smart grid technology has been introduced as a healing approach in terms of using energy more efficiently. This study made an effort to have some discussions around smart grid technology development in the United States by patent analysis and forecasting. The outcomes in both technology …


Bayesian Geoacoustic Inversion Using Wind-Driven Ambient Noise, Jorge E. Quijano, Stan E. Dosso, Jan Dettmer, Lisa M. Zurk, Martin Siderius, Chris H. Harrison Apr 2012

Bayesian Geoacoustic Inversion Using Wind-Driven Ambient Noise, Jorge E. Quijano, Stan E. Dosso, Jan Dettmer, Lisa M. Zurk, Martin Siderius, Chris H. Harrison

Electrical and Computer Engineering Faculty Publications and Presentations

This paper applies Bayesian inversion to bottom-loss data derived from wind-driven ambient noisemeasurements from a vertical line array to quantify the information content constraining seabed geoacoustic parameters. The inversion utilizes a previously proposed ray-based representation of the ambient noise field as a forward model for fast computations of bottom loss data for a layered seabed. This model considers the effect of the array’s finite aperture in the estimation of bottom loss and is extended to include the wind speed as the driving mechanism for the ambient noise field. The strength of this field relative to other unwanted noise mechanisms defines …


Application Of Inter-Die Rank Statistics In Defect Detection, Vivek Bakshi Mar 2012

Application Of Inter-Die Rank Statistics In Defect Detection, Vivek Bakshi

Dissertations and Theses

This thesis presents a statistical method to identify the test escapes. Test often acquires parametric measurements as a function of logical state of a chip. The usual method of classifying chips as pass or fail is to compare each state measurement to a test limit. Subtle manufacturing defects are escaping the test limits due to process variations in deep sub-micron technologies which results in mixing of healthy and faulty parametric test measurements. This thesis identifies the chips with subtle defects by using rank order of the parametric measurements. A hypothesis is developed that a defect is likely to disturb the …


Emergent Criticality Through Adaptive Information Processing In Boolean Networks, Alireza Goudarzi, Christof Teuscher, Natali Gulbahce, Thimo Rohlf Mar 2012

Emergent Criticality Through Adaptive Information Processing In Boolean Networks, Alireza Goudarzi, Christof Teuscher, Natali Gulbahce, Thimo Rohlf

Electrical and Computer Engineering Faculty Publications and Presentations

We study information processing in populations of Boolean networks with evolving connectivity and systematically explore the interplay between the learning capability, robustness, the network topology, and the task complexity. We solve a long-standing open question and find computationally that, for large system sizes N, adaptive information processing drives the networks to a critical connectivity K_{c}=2. For finite size networks, the connectivity approaches the critical value with a power law of the system size N. We show that network learning and generalization are optimized near criticality, given that the task complexity and the amount of information provided surpass threshold values. Both …


Power Characteristics Of Homogeneously Broadened Index-Antiguided Waveguide Lasers, Chaofan Wang, Tsing-Hua Her, Lee W. Casperson Mar 2012

Power Characteristics Of Homogeneously Broadened Index-Antiguided Waveguide Lasers, Chaofan Wang, Tsing-Hua Her, Lee W. Casperson

Electrical and Computer Engineering Faculty Publications and Presentations

A model is reported that describes a bidirectional homogeneously broadened index-antiguided (IAG) slab laser having arbitrary single-pass gain and distributed losses. Maximum extraction efficiency and corresponding optimum output coupling are determined for various values of unsaturated gain and loss per pass. A method is proposed to determine the intrinsic laser parameters from output power measurements.


Measurement And Modeling Of Passive Surface Mount Devices On Fr4 Substrates, Rahulkumar Sadanand Koche Jan 2012

Measurement And Modeling Of Passive Surface Mount Devices On Fr4 Substrates, Rahulkumar Sadanand Koche

Dissertations and Theses

Passive components like resistors, capacitors and inductors are used in every electronic system. These are the very basic components which affect the system performance at higher frequencies and it is necessary to understand and model the behavior of these components in a very accurate manner. This work focuses on utilizing Printed Circuit Board (PCB) test boards, or fixtures, made of FR4 for characterizing Surface Mount Device (SMD) components. Agilent's Advanced Design System (ADS) microwave circuit simulation software was used for designing the microstrip transmission lines as well as for generating the layout for manufacturing of the PCB. SMD resistors, capacitors …


Material Characterization Of Zinc Oxide In Bulk And Nanowire Form At Terahertz Frequencies, Forest Emerson Kernan Jan 2012

Material Characterization Of Zinc Oxide In Bulk And Nanowire Form At Terahertz Frequencies, Forest Emerson Kernan

Dissertations and Theses

Many new applications are being proposed and developed for use in the terahertz (THz) frequency region. Similarly, many new materials are being characterized for possible use in this area. Nanostructured forms are of particular interest since they may yield desirable properties, but they remain especially challenging to characterize. This work focuses on the characterization of zinc oxide (ZnO) in bulk and nanowire form. A method for characterizing nanostructures at THz by use of a parallel-plate waveguide (PPWG) is presented. This method is novel in that it is simple, both in theory and practice, and does not require the use of …


Evolved Design Of A Nonlinear Proportional Integral Derivative (Npid) Controller, Shubham Chopra Jan 2012

Evolved Design Of A Nonlinear Proportional Integral Derivative (Npid) Controller, Shubham Chopra

Dissertations and Theses

This research presents a solution to the problem of tuning a PID controller for a nonlinear system. Many systems in industrial applications use a PID controller to control a plant or the process. Conventional PID controllers work in linear systems but are less effective when the plant or the process is nonlinear because PID controllers cannot adapt the gain parameters as needed. In this research we design a Nonlinear PID (NPID) controller using a fuzzy logic system based on the Mamdani type Fuzzy Inference System to control three different DC motor systems. This fuzzy system is responsible for adapting the …


Experimental Study Of Fault Cones And Fault Aliasing, Vedanth Bilagi Jan 2012

Experimental Study Of Fault Cones And Fault Aliasing, Vedanth Bilagi

Dissertations and Theses

The test of digital integrated circuits compares the test pattern results for the device under test (DUT) to the expected test pattern results of a standard reference. The standard response is typically obtained from simulations. The test pattern and response are created and evaluated assuming ideal test conditions. The standard response is normally stored within automated test equipment (ATE). However the use of ATE is the major contributor to the test cost. This thesis explores an alternative strategy to the standard response. As an alternative to the stored standard response, the response is estimated by fault tolerant technique. The purpose …


Digital Fabric, Sudheer Goshi Jan 2012

Digital Fabric, Sudheer Goshi

Dissertations and Theses

Continuing advances with VLSI have enabled engineers to build high performance computer systems to solve complex problems. The real-world problems and tasks like pattern recognition, speech recognition, etc. still remain elusive to the most advanced computer systems today. Many advances in the science of computer design and technology are coming together to enable the creation of the next-generation computing machines to solve real-world problems, which the human brain does with ease. One such engineering advance is the field of neuromorphic engineering, which tries to establish closer links to biology and help us investigate the problem of designing better computing machines. …


Scale Invariant Object Recognition Using Cortical Computational Models And A Robotic Platform, Danny Voils Jan 2012

Scale Invariant Object Recognition Using Cortical Computational Models And A Robotic Platform, Danny Voils

Dissertations and Theses

This paper proposes an end-to-end, scale invariant, visual object recognition system, composed of computational components that mimic the cortex in the brain. The system uses a two stage process. The first stage is a filter that extracts scale invariant features from the visual field. The second stage uses inference based spacio-temporal analysis of these features to identify objects in the visual field. The proposed model combines Numenta's Hierarchical Temporal Memory (HTM), with HMAX developed by MIT's Brain and Cognitive Science Department. While these two biologically inspired paradigms are based on what is known about the visual cortex, HTM and HMAX …


A Fault-Tolerant Alternative To Lockstep Triple Modular Redundancy, Andrew Lockett Baldwin Jan 2012

A Fault-Tolerant Alternative To Lockstep Triple Modular Redundancy, Andrew Lockett Baldwin

Dissertations and Theses

Semiconductor manufacturing defects adversely affect yield and reliability. Manufacturers expend vast resources to reduce defects within their processes. As the minimum feature size get smaller, defects become increasingly difficult to prevent. Defects can change the behavior of a logic circuit resulting in a fault. Manufacturers and designers may improve yield, reliability, and profitability by using design techniques that make products robust even in the presence of faults. Triple modular redundancy (TMR) is a fault tolerant technique commonly used to mask faults using voting outcomes from three processing elements (PE). TMR is effective at masking errors as long as no more …


Memristor-Based Reservoir Computing, Manjari S. Kulkarni Jan 2012

Memristor-Based Reservoir Computing, Manjari S. Kulkarni

Dissertations and Theses

In today's nanoscale era, scaling down to even smaller feature sizes poses a significant challenge in the device fabrication, the circuit, and the system design and integration. On the other hand, nanoscale technology has also led to novel materials and devices with unique properties. The memristor is one such emergent nanoscale device that exhibits non-linear current-voltage characteristics and has an inherent memory property, i.e., its current state depends on the past. Both the non-linear and the memory property of memristors have the potential to enable solving spatial and temporal pattern recognition tasks in radically different ways from traditional binary transistor-based …


Distributed Solar Photovoltaic Grid Integration System : A Case Study For Performance, Ming Shen Jan 2012

Distributed Solar Photovoltaic Grid Integration System : A Case Study For Performance, Ming Shen

Dissertations and Theses

The needs to the sustainable development of electricity, energy efficiency improvement, and environment pollution reduction have favored the development of distributed generation (DG). But the problems come with increasing DG penetration in distribution networks. This thesis presents the Solar Energy Grid Integration System (SEGIS) Stage III project done by Portland General Electric (PGE), Advanced Energy, Sandia National Lab on a PGE selected distribution feeder. The feeder has six monitored commercial solar PV systems connected. The total power output from the PV systems has the potential to reach 30% of the feeder load. The author analyzes the performance of the solar …


Passive Acoustic Vessel Localization, Pasang Sherpa Suwal Jan 2012

Passive Acoustic Vessel Localization, Pasang Sherpa Suwal

Dissertations and Theses

This thesis investigates the development of a low-cost passive acoustic system for localizing moving vessels to monitor areas where human activities such as fishing, snorkeling and poaching are restricted. The system uses several off-the-shelf sensors with unsynchronized clocks where the Time Difference of Arrival (TDOA) or time delay is extracted by cross-correlation of the signal between paired sensors. The cross-correlation function uses phase correlation or Phase Transform (PHAT) which whitens the cross-spectrum in order to de-emphasize dominant frequency components. Using the locations of pairs of sensors as foci, hyperbolic equations can be defined using the time delay between them. With …