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Full-Text Articles in Engineering

Synthesis Of Irreversible Incompletely Specified Multi-Output Functions To Reversible Eosops Circuits With Pse Gates, Robert Adrian Fiszer Dec 2014

Synthesis Of Irreversible Incompletely Specified Multi-Output Functions To Reversible Eosops Circuits With Pse Gates, Robert Adrian Fiszer

Dissertations and Theses

As quantum computers edge closer to viability, it becomes necessary to create logic synthesis and minimization algorithms that take into account the particular aspects of quantum computers that differentiate them from classical computers. Since quantum computers can be functionally described as reversible computers with superposition and entanglement, both advances in reversible synthesis and increased utilization of superposition and entanglement in quantum algorithms will increase the power of quantum computing.

One necessary component of any practical quantum computer is the computation of irreversible functions. However, very little work has been done on algorithms that synthesize and minimize irreversible functions into a …


Generalized Framework For Similarity Measure Of Time Series, Hongsheng Yin, Honggang Qi, Jingwen Xu, William N. N. Hung, Xiaoyu Song Dec 2014

Generalized Framework For Similarity Measure Of Time Series, Hongsheng Yin, Honggang Qi, Jingwen Xu, William N. N. Hung, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

Currently, there is no definitive and uniform description for the similarity of time series, which results in difficulties for relevant research on this topic. In this paper, we propose a generalized framework to measure the similarity of time series. In this generalized framework, whether the time series is univariable or multivariable, and linear transformed or nonlinear transformed, the similarity of time series is uniformly defined using norms of vectors or matrices.The definitions of the similarity of time series in the original space and the transformed space are proved to be equivalent. Furthermore, we also extend the theory on similarity of …


Detection Of Variable Retention Time In Dram, Neraj Kumar Nov 2014

Detection Of Variable Retention Time In Dram, Neraj Kumar

Dissertations and Theses

This thesis investigates a test method to detect the presence of Variable Retention Time (VRT) bits in manufactured DRAM. The VRT bits retention time is modeled as a 2-state random telegraph process that includes miscorrelation between test and use. The VRT defect is particularly sensitive to test and use conditions. A new test method is proposed to screen the VRT bits by simulating the use conditions during manufacturing test. Evaluation of the proposed test method required a bit-level VRT model to be parameterized as a function of temperature and voltage conditions. The complete 2-state VRT bit model combines models for …


Unconventional Computing Catechism, Christof Teuscher Nov 2014

Unconventional Computing Catechism, Christof Teuscher

Electrical and Computer Engineering Faculty Publications and Presentations

What makes a new paradigm or technology promising? What should science, research, and industry invest money in? Is there a life after CMOS electronics? And will the vacuum tube be back? While one cannot predict the future, one can still learn from the past. Over the last decade, unconventional computing developed into a major new research area with the goal to look beyond existing paradigms. In this Perspective, we reflect on the current state of the field and propose a set of questions that anyone working in unconventional computing should be able to answer in order to assess the potential …


Geoacoustic Inversion Of Ship Radiated Noise In Shallow Water Using Data From A Single Hydrophone, Steven E. Crocker, Peter L. Nielsen, James H. Miller, Martin Siderius Nov 2014

Geoacoustic Inversion Of Ship Radiated Noise In Shallow Water Using Data From A Single Hydrophone, Steven E. Crocker, Peter L. Nielsen, James H. Miller, Martin Siderius

Electrical and Computer Engineering Faculty Publications and Presentations

The Centre for Maritime Research and Experimentation conducted a geoacoustic inverse experiment in the Mediterranean Sea in the summer of 2012. Among the objectives was to employ an autono- mous underwater vehicle to collect acoustic data to invert for properties of the seafloor. Inversion results for the compression wave speed in the bottom and the source spectrum of the R/V Alliance during a close approach to the bottom moored vehicle are presented. The estimated wave speed was 1529 m/s (r ¼ 10). The source spectrum of the Alliance was estimated across more than six octaves of frequency.


Analog Implicit Functional Testing Using Supervised Machine Learning, Neerja Pramod Bawaskar Oct 2014

Analog Implicit Functional Testing Using Supervised Machine Learning, Neerja Pramod Bawaskar

Dissertations and Theses

Testing analog circuits is more difficult than digital circuits. The reasons for this difficulty include continuous time and amplitude signals, lack of well-accepted testing techniques and time and cost required for its realization. The traditional method for testing analog circuits involves measuring all the performance parameters and comparing the measured parameters with the limits of the data-sheet specifications. Because of the large number of data-sheet specifications, the test generation and application requires long test times and expensive test equipment.

This thesis proposes an implicit functional testing technique for analog circuits that can be easily implemented in BIST circuitry. The proposed …


Training Set Design For Test Removal Classication In Ic Test, Nagarjun Hassan Ranganath Oct 2014

Training Set Design For Test Removal Classication In Ic Test, Nagarjun Hassan Ranganath

Dissertations and Theses

This thesis reports the performance of a simple classifier as a function of its training data set. The classifier is used to remove analog tests and is named the Test Removal Classifier (TRC).

The thesis proposes seven different training data set designs that vary by the number of wafers in the data set, the source of the wafers and the replacement scheme of the wafers. The training data set size ranges from a single wafer to a maximum of five wafers. Three of the training data sets include wafers from the Lot Under Test (LUT). The training wafers in the …


Slm-Based Fourier Differential Interference Contrast Microscopy, Sahand Noorizadeh Oct 2014

Slm-Based Fourier Differential Interference Contrast Microscopy, Sahand Noorizadeh

Dissertations and Theses

Optical phase microscopy provides a view of objects that have minimal to no effect on the detected intensity of light that are unobservable by standard microscopy techniques. Since its inception just over 60 years ago that gave us a vision to an unseen world and earned Frits Zernike the Nobel prize in physics in 1953, phase microscopy has evolved to find various applications in biological cell imaging, crystallography, semiconductor failure analysis, and more. Two common and commercially available techniques are phase contrast and differential interference contrast (DIC). In phase contrast method, a large portion of the unscattered light that accounts …


Substation Bay Modeling And Seismic Sensitivity Study, Robert C.H. London Oct 2014

Substation Bay Modeling And Seismic Sensitivity Study, Robert C.H. London

Civil and Environmental Engineering Master's Project Reports

The performance of high voltage electrical substations during an earthquake significantly contributes to regional resilience by providing electrical power to public entities, businesses and homes following an earthquake. Utilities try to minimize the seismic impact by qualifying individual equipment, but rarely evaluate the interconnected substation bay as a whole. In this study, three detailed numerical models were developed using the seismic qualification reports of individual electrical equipment as basis for the components within 115kV, 230kV, and 500 kV substation bay systems. The substation bays were evaluated without interconnectivity of the components and with rigid bus connectivity between components. The models …


Last Mile Asset Monitoring: Low Cost Rapid Deployment Asset Monitoring, Zdenek Zumr Sep 2014

Last Mile Asset Monitoring: Low Cost Rapid Deployment Asset Monitoring, Zdenek Zumr

Dissertations and Theses

Installation and utilization of residential distribution transformers has not changed substantially over a long period of time. Utilities typically size their transformers based on a formula that takes into account broadly what types and how many dwellings will be connected.

Most new residential dwellings feature 200 Amp service per household with an anticipated energy demand of under 20,000 kWh per year. Average electrical energy consumption varies from state to state but averages to 11,280 kWh per year. Energy demand is expected to fall into a typical residential load curve that shows increased demand early in the morning, then decreasing during …


Formalization Of Matrix Theory In Hol4, Zhiping Shi, Yan Zhang, Zhenke Liu, Xinan Kang, Yong Guan, Jie Zhang, Xiaoyu Song Aug 2014

Formalization Of Matrix Theory In Hol4, Zhiping Shi, Yan Zhang, Zhenke Liu, Xinan Kang, Yong Guan, Jie Zhang, Xiaoyu Song

Electrical and Computer Engineering Faculty Publications and Presentations

Matrix theory plays an important role in modeling linear systems in engineering and science. To model and analyze the intricate behavior of complex systems, it is imperative to formalize matrix theory in a metalogic setting. This paper presents the higherorder logic (HOL) formalization of the vector space and matrix theory in the HOL4 theorem proving system. Formalized theories include formal definitions of real vectors and matrices, algebraic properties, and determinants, which are verified in HOL4. Two case studies, modeling and verifying composite two-port networks and state transfer equations, are presented to demonstrate the applicability and effectiveness of our work.


Advances In Aquatic Target Localization With Passive Sonar, John Thomas Gebbie Jul 2014

Advances In Aquatic Target Localization With Passive Sonar, John Thomas Gebbie

Dissertations and Theses

New underwater passive sonar techniques are developed for enhancing target localization capabilities in shallow ocean environments. The ocean surface and the seabed act as acoustic mirrors that reflect sound created by boats or subsurface vehicles, which gives rise to echoes that can be heard by hydrophone receivers (underwater microphones). The goal of this work is to leverage this "multipath" phenomenon in new ways to determine the origin of the sound, and thus the location of the target. However, this is difficult for propeller driven vehicles because the noise they produce is both random and continuous in time, which complicates its …


Combined Traction And Energy Recovery Motor For Electric Vehicles, James Long, Xin Wang, Claude Kansaku, Brian Moravec Jul 2014

Combined Traction And Energy Recovery Motor For Electric Vehicles, James Long, Xin Wang, Claude Kansaku, Brian Moravec

TREC Final Reports

Electric vehicle manufacturers are looking for ways to optimize energy use for vehicle range extension and reduction of battery capacity. Electric motors have lower efficiencies at very low speed and high torque. This is typically at vehicle launch from standstill, at very low speeds, and during energy regeneration at lower speeds and approaching standstill. The KersTech solution is a breakthrough technology allowing supplement of the electric drive with a hydraulic drive, active in lower speeds ranges, dropping out as the electric motor takes over in its higher efficiency range of operation. The report consists of four parts. Part I presents …


Passive Localization Of Noise-Producing Targets Using A Compact Volumetric Array, John Gebbie, Martin Siderius, Peter L. Nielsen, James Miller Jul 2014

Passive Localization Of Noise-Producing Targets Using A Compact Volumetric Array, John Gebbie, Martin Siderius, Peter L. Nielsen, James Miller

Electrical and Computer Engineering Faculty Publications and Presentations

A technique is presented for passively localizing multiple noise-producing targets by cross-correlating the elevation beams of a compact volumetric array on separate bearings. A target’s multipath structure inherently contains information about its range; however, unknown, random noise waveforms make time separation of individual arrivals difficult. Ocean ambient noise has previously been used to measure multipath delays to the seabed by cross-correlating the beams of a vertical line array [Siderius, Song, Gerstoft, Hodgkiss, Hursky, and Harrison, J. Acoust. Soc. Am. 127, 2193–2200 (2010)], but this methodology has not been applied to distant noise sources having non-vertical arrivals. The technique presented in …


Probabilistic Analysis For Reliable Logic Circuits, Scott Blakely Jun 2014

Probabilistic Analysis For Reliable Logic Circuits, Scott Blakely

Dissertations and Theses

Continued aggressive scaling of electronic technology poses obstacles for maintaining circuit reliability. To this end, analysis of reliability is of increasing importance. Large scale number of inputs and gates or correlations of failures render such analysis computationally complex. This paper presents an accurate framework for reliability analysis of logic circuits, while inherently handling reconvergent fan-out without additional complexity. Combinational circuits are modeled stochastically as Discrete-Time Markov Chains, where propagation of node logic levels and error probability distributions through circuitry are used to determine error probabilities at nodes in the circuit. Model construction is scalable, as it is done so on …


A 3.6 Ghz Doherty Power Amplifier With A 40 Dbm Saturated Output Power Using Gan On Sic Hemt Devices, Bryant Baker Jun 2014

A 3.6 Ghz Doherty Power Amplifier With A 40 Dbm Saturated Output Power Using Gan On Sic Hemt Devices, Bryant Baker

Dissertations and Theses

This manuscript describes the design, development, and implementation of a linear high efficiency power amplifier. The symmetrical Doherty power amplifier utilizes TriQuint's 2nd Generation Gallium Nitride (GaN) on Silicon Carbide (SiC) High Electron Mobility Transistor (HEMT) devices (T1G6001032-SM) for a specified design frequency of 3.6 GHz and saturated output power of 40 dBm. Advanced Design Systems (ADS) simulation software, in conjunction with Modelithic's active and passive device models, were used during the design process and will be evaluated against the final measured results. The use of these device models demonstrate a successful first-pass design, putting less dependence on classical load …


An Assessment Model For Energy Efficiency Program Planning In Electric Utilities: Case Of The Pacific Of Northwest U.S.A., Ibrahim Iskin Jun 2014

An Assessment Model For Energy Efficiency Program Planning In Electric Utilities: Case Of The Pacific Of Northwest U.S.A., Ibrahim Iskin

Dissertations and Theses

Energy efficiency stands out with its potential to address a number of challenges that today's electric utilities face, including increasing and changing electricity demand, shrinking operating capacity, and decreasing system reliability and flexibility. Being the least cost and least risky alternative, the share of energy efficiency programs in utilities' energy portfolios has been on the rise since the 1980s, and their increasing importance is expected to continue in the future. Despite holding great promise, the ability to determine and invest in only the most promising program alternatives plays a key role in the successful use of energy efficiency as a …


Coherence Extrapolation For Underwater Ambient Noise, Jorge Quijano, Stan E. Dosso, Martin Siderius, Lanfranco Muzi Jun 2014

Coherence Extrapolation For Underwater Ambient Noise, Jorge Quijano, Stan E. Dosso, Martin Siderius, Lanfranco Muzi

Electrical and Computer Engineering Faculty Publications and Presentations

This paper considers extrapolation of the vertical coherence of surface-generated oceanic ambient noise to simulate measurements made on a longer sensor array. The extrapolation method consists of projecting the noise coherence measured with a limited aperture array into the domain spanned by prolate spheroidal wave functions, which are an orthogonal basis defined by array parameters and the noise frequency. Using simulated data corresponding to selected multi-layered seabeds as ground truth, the performance of the extrapolation method is explored. Application of the technique is also demonstrated on experimental data.


Characterization Of Li-Air Batteries: Lithium Peroxide Formation In Li-Air Electrodes, Claudia Torres Garibay, Jeremiah Deboever Jun 2014

Characterization Of Li-Air Batteries: Lithium Peroxide Formation In Li-Air Electrodes, Claudia Torres Garibay, Jeremiah Deboever

TREC Final Reports

Li-air batteries are attractive candidates to be used in electric vehicles (EV) due to their high theoretical capacity, which results in an improved range, a requirement to make EV competitive against fossil fuel powered vehicles. However, Li-air battery technology is considered to be far from commercialization, due to its short lifespan. The decomposition of the electrolyte and its effect on cyclablity has been widely studied, no so much the cathode. This work will make use of recently reported novel adaptation of titration techniques to study cathode degradation in Li-air batteries, along capacity, cyclability, and EIS studies, to characterize the effect …


An Eigenvector-Based Test For Local Stationarity Applied To Array Processing, Jorge Quijano, Lisa M. Zurk Jun 2014

An Eigenvector-Based Test For Local Stationarity Applied To Array Processing, Jorge Quijano, Lisa M. Zurk

Electrical and Computer Engineering Faculty Publications and Presentations

In sonar array processing, a challenging problem is the estimation of the data covariance matrix in the presence of moving targets in the water column, since the time interval of data local stationarity is limited. This work describes an eigenvector-based method for proper data segmentation into intervals that exhibit local stationarity, providing data-driven higher bounds for the number of snapshots available for computation of time-varying sample covariance matrices. Application of the test is illustrated with simulated data in a horizontal array for the detection of a quiet source in the presence of a loud interferer.


Design And Prototyping Of An Antenna-Coupled Cryotron, Shauna Jensen May 2014

Design And Prototyping Of An Antenna-Coupled Cryotron, Shauna Jensen

Dissertations and Theses

Grid-scale integration of renewable energy sources and smart grid devices has created new demands in flexible power conversion. State-of-the-art semiconductor power switches present limitations in power handling capability, as well as forward and reverse breakdown voltages. Superconducting materials are a viable alternative due to their robustness against high ampacities, large electric fields and abrupt changes in power flow. This work pays focus to material testing and apparatus design for an antenna-coupled cryotron (ACC), which is a superconducting power switch.
Design, fabrication and testing are examined for a longitudinal resonant cavity, paired with monopole transmit and modified slot receive antennae. These …


Agent-Based Control Of A Flapping Wing Micro Aerial Vehicle, Michal Podhradský May 2014

Agent-Based Control Of A Flapping Wing Micro Aerial Vehicle, Michal Podhradský

Student Research Symposium

Flapping wing micro aerial vehicles (FWMAVs) are biomimetic vehicles, because they imitate insects in the way they fly. FWMAVs are very small and highly manoeuvrable and can be used in reconnaissance, environmental monitoring, search & rescue, and other applications. The goal of the project is to develop & verify an agent based flight controller for FWMAV that can adapt to different flight conditions, actuator failures, and different vehicles while delivering constant performance. Agent based control was successfully applied in industry and distributed applications, but to our best knowledge never in an actual flying vehicle. Agent based control utilizes machine learning, …


The Smart Clock, Cory Koehler, Addison Loda, Hannah Posey-Scholl, Isak Rask May 2014

The Smart Clock, Cory Koehler, Addison Loda, Hannah Posey-Scholl, Isak Rask

PSU High School Innovation Challenge

Modern technology continues to change and improve constantly as people find ways to make things faster, smaller, and better - but these changes often leave the elderly behind. This year’s Innovation Challenge asked groups to focus on how to create and improve technology geared towards the aging generations. For our initial research, the Grant High School team and mentors visited an elderly care center and interviewed a few of the residents, asking what types of technology currently improve their lives, and what types of technology could potentially improve their lives.

The Problem: After the interviews, we were able to identify …


Anisotropy Of The Reynolds Stress Tensor In The Wakes Of Counter-Rotating Wind Turbine Arrays, Nicholas Michael Hamilton Apr 2014

Anisotropy Of The Reynolds Stress Tensor In The Wakes Of Counter-Rotating Wind Turbine Arrays, Nicholas Michael Hamilton

Dissertations and Theses

A wind turbine array was constructed in the wind tunnel at Portland State University in a standard Cartesian arrangement. Configurations of the turbine array were tested with rotor blades set to rotate in either a clockwise or counter-clockwise sense. Measurements of velocity were made with stereo particle-image velocimetry. Mean statistics of velocities and Reynolds stresses clearly show the effect of direction of rotation of rotor blades for both entrance and exit row turbines. Rotational sense of the turbine blades is visible in the mean spanwise velocity W and the Reynolds shear stress -[macron over vw]. The normalized anisotropy tensor was …


The Design, Implementation, Assessment, And Evaluation Of A Power Systems Protection Laboratory Curriculum, Jennifer Ferris Mar 2014

The Design, Implementation, Assessment, And Evaluation Of A Power Systems Protection Laboratory Curriculum, Jennifer Ferris

Dissertations and Theses

Over the last the last three decades, there has been a significant and documented decrease of power engineering curriculum within U.S. electrical engineering programs. Development of lifelong learners capable of critical and independent thinking is required to replace the large number of upcoming retirees from the industry and to prepare for the engineering challenges new technologies, laws and regulations are bringing to the electrical power system. In response to these challenges, Portland State University redesigned its BSEE and MSECE power engineering programs in order to create a launching pad for successful power engineering careers. A course series on power system …


Characterization If Li-Air Batteries Influence Of Cathode Degradation: Demonstration Of Progress, Claudia Torres Garibay, Jeremiah Deboever Feb 2014

Characterization If Li-Air Batteries Influence Of Cathode Degradation: Demonstration Of Progress, Claudia Torres Garibay, Jeremiah Deboever

TREC Project Briefs

Li-air batteries are attractive candidates to be used in electric vehicles (EV) due to their high theoretical capacity, which results in an improved range, a requirement to make EV competitive against fossil fuel powered vehicles. However, Li-air battery technology is considered to be far from commercialization, due to its short lifespan. The decomposition of the electrolyte and its effect on cyclablity has been widely studied, no so much the cathode. The presence of undesirable reaction by-products at the cathode that affect the battery performance has been quantified through XRD and SEM. This work will make use of recently reported novel …


Functional Verification Of High Performance Adders In Coq, Qian Wang, Xiaoyu Song, Ming Gu, Jiaguang Sun Jan 2014

Functional Verification Of High Performance Adders In Coq, Qian Wang, Xiaoyu Song, Ming Gu, Jiaguang Sun

Electrical and Computer Engineering Faculty Publications and Presentations

Addition arithmetic design plays a crucial role in high performance digital systems. The paper proposes a systematic method to formalize and verify adders in a formal proof assistant COQ. The proposed approach succeeds in formalizing the gate-level implementations and verifying the functional correctness of the most important adders of interest in industry, in a faithful, scalable, and modularized way. The methodology can be extended to other adder architectures as well.


A Comparative Study Of Reservoir Computing For Temporal Signal Processing, Alireza Goudarzi, Peter Banda, Matthew R. Lakin, Christof Teuscher, Darko Stefanovic Jan 2014

A Comparative Study Of Reservoir Computing For Temporal Signal Processing, Alireza Goudarzi, Peter Banda, Matthew R. Lakin, Christof Teuscher, Darko Stefanovic

Computer Science Faculty Publications and Presentations

Reservoir computing (RC) is a novel approach to time series prediction using recurrent neural networks. In RC, an input signal perturbs the intrinsic dynamics of a medium called a reservoir. A readout layer is then trained to reconstruct a target output from the reservoir's state. The multitude of RC architectures and evaluation metrics poses a challenge to both practitioners and theorists who study the task-solving performance and computational power of RC. In addition, in contrast to traditional computation models, the reservoir is a dynamical system in which computation and memory are inseparable, and therefore hard to analyze. Here, we compare …


Reliability Analysis For Chain Topology Wireless Sensor Networks With Multiple-Sending Transmission Scheme, Jie Cai, Xiaoyu Song, Jinyuan Wang, Ming Gu Jan 2014

Reliability Analysis For Chain Topology Wireless Sensor Networks With Multiple-Sending Transmission Scheme, Jie Cai, Xiaoyu Song, Jinyuan Wang, Ming Gu

Electrical and Computer Engineering Faculty Publications and Presentations

Reliability analysis is a key problem in wireless sensor networks (WSNs). The primary contribution of this paper is an in-depth study of the reliability of a chain topology wireless sensor network with multiple-sending scheme. We study the wireless link reliability for the fading channels. The node energy availability for the source and relay nodes is investigated in terms of the limited node energy. The instantaneous network reliability and the mean time to failure are derived. Finally, the initial node energy allocation scheme is proposed to balance the lifetime of each sensor node, thus reducing the total energy consumption. The simulation …


Cost Minimization Approach To Synthesis Of Linear Reversible Circuits, Ben Schaeffer, Marek Perkowski Jan 2014

Cost Minimization Approach To Synthesis Of Linear Reversible Circuits, Ben Schaeffer, Marek Perkowski

Electrical and Computer Engineering Faculty Publications and Presentations

This paper presents a heuristic cost minimization approach to synthesizing linear reversible circuits. Two bidirectional linear reversible circuit synthesis methods are introduced, the Alternating Elimination with Cost Minimization method (AECM) and the Multiple CNOT Gate method (MCG). Algorithms, example syntheses, and extensions to these methods are presented. An MCG variant which incorporates line reordering is introduced. Tests comparing the new cost minimization methods with the best known method for large circuits are presented. Results show that of the three methods MCG had the lowest average CNOT gate counts for linear reversible circuits up to 24 lines, and that AECM had …