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Portland State University

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2014

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Articles 1 - 30 of 59

Full-Text Articles in Engineering

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 …

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Sensitivity Of Columbia Basin Runoff To Long-Term Changes In Multi-Model Cmip5 Precipitation Simulations, Mehmet Demirel, Hamid Moradkhani Dec 2014

Sensitivity Of Columbia Basin Runoff To Long-Term Changes In Multi-Model Cmip5 Precipitation Simulations, Mehmet Demirel, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

In this study, we used precipitation elasticity index of streamflow, to reflect on the sensitivity of streamflow to changes in future precipitation. We estimated precipitation elasticity of streamflow from: (1) simulated streamflow by the VIC model using observed precipitation for the current climate (1963–2003); (2) simulated streamflow by the VIC model using simulated precipitation from 10 GCM - CMIP5 dataset for the future climate (2010–2099) including two different pathways (RCP4.5 and RCP8.5) and two different downscaled products (BCSD and MACA). The hydrological model was calibrated at 1/16 latitude-longitude resolution and the simulated streamflow was routed to the subbasin outlets of …

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Improved Bayesian Multi-Modeling: Integration Of Copulas And Bayesian Model Averaging, Shahrbanou Madadgar, Hamid Moradkhani Nov 2014

Improved Bayesian Multi-Modeling: Integration Of Copulas And Bayesian Model Averaging, Shahrbanou Madadgar, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Bayesian Model Averaging (BMA) is a popular approach to combine hydrologic forecasts from individual models, and characterize the uncertainty induced by model structure. In the original form of BMA, the conditional probability density function (PDF) of each model is assumed to be a particular probability distribution (e.g. Gaussian, gamma, etc.). If the predictions of any hydrologic model do not follow certain distribution, a data transformation procedure is required prior to model averaging. Moreover, it is strongly recommended to apply BMA on unbiased forecasts, whereas it is sometimes difficult to effectively remove bias from the predictions of complex hydrologic models. To …

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Can Protected Bike Lanes Help Close The Gender Gap In Cycling? Lessons From Five Cities, Jennifer Dill, Tara Goddard, Christopher Monsere, Nathan Mcneil Nov 2014

Can Protected Bike Lanes Help Close The Gender Gap In Cycling? Lessons From Five Cities, Jennifer Dill, Tara Goddard, Christopher Monsere, Nathan Mcneil

Urban Studies and Planning Faculty Publications and Presentations

Even in areas with increased levels of bicycling, there remains a significant “gender gap” in bicycling in the United States, in contrast to many other countries with high rates of bicycling. The primary objective of this paper was to explore whether protected bike lanes could help reduce the gender gap. To do so, the authors used survey data from a comprehensive evaluation of protected bike lanes in five large U.S. cities (Austin, TX, Chicago, IL, Portland, OR, San Francisco, CA, and Washington, DC) that included survey responses of 1,111 intercepted bicyclists and 2,283 residents. Both men and women overwhelmingly felt …

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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 …

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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.

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A Regression Approach For Estimation Of Anthropogenic Heat Flux Based On A Bottom-Up Air Pollutant Emission Database, Sanghyun Lee, Stuart A. Mckeen, David J. Sailor Oct 2014

A Regression Approach For Estimation Of Anthropogenic Heat Flux Based On A Bottom-Up Air Pollutant Emission Database, Sanghyun Lee, Stuart A. Mckeen, David J. Sailor

Mechanical and Materials Engineering Faculty Publications and Presentations

A statistical regression method is presented for estimating hourly anthropogenic heat flux (AHF) using an anthropogenic pollutant emission inventory for use in mesoscale meteorological and air-quality modeling. Based on bottom-up AHF estimated from detailed energy consumption data and anthropogenic pollutant emissions of carbon monoxide (CO) and nitrogen oxides (NOx) in the US National Emission Inventory year 2005 (NEI-2005), a robust regression relation between the AHF and the pollutant emissions is obtained for Houston. This relation is a combination of two power functions (Y = aXb) relating CO and NOx emissions to AHF, giving a determinant …

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Technological Forecasting Of Supercomputer Development: The March To Exascale Computing, Dong-Joon Lim, Timothy R. Anderson, Tom Shott Oct 2014

Technological Forecasting Of Supercomputer Development: The March To Exascale Computing, Dong-Joon Lim, Timothy R. Anderson, Tom Shott

Engineering and Technology Management Faculty Publications and Presentations

Advances in supercomputers have come at a steady pace over the past 20 years. The next milestone is to build an Exascale computer however this requires not only speed improvement but also significant enhancements for energy efficiency and massive parallelism. This paper examines technological progress of supercomputer development to identify the innovative potential of three leading technology paths toward Exascale development: hybrid system, multicore system and manycore system. Performance measurement and rate of change calculation were made by Technology Forecasting using Data Envelopment Analysis (TFDEA.) The results indicate that the current level of technology and rate of progress can achieve …

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Choosing Effective Dates From Multiple Optima In Technology Forecasting Using Data Envelopment Analysis (Tfdea), Dong-Joon Lim, Timothy R. Anderson, Oliver Inman Oct 2014

Choosing Effective Dates From Multiple Optima In Technology Forecasting Using Data Envelopment Analysis (Tfdea), Dong-Joon Lim, Timothy R. Anderson, Oliver Inman

Engineering and Technology Management Faculty Publications and Presentations

Technology Forecasting using Data Envelopment Analysis (TFDEA) provides an effective means to forecast technological capability over time without the burden of fixed a priori weighting schemes. However, there are situations where result reproduction can be a challenge as first pointed out in a previous Technological Forecasting and Social Change article. When using a commonly used extension of TFDEA, there are circumstances where multiple optimal solutions can complicate analysis. This paper addresses this issue through extending the TFDEA model in a manner consistent with common Data Envelopment Analysis (DEA) techniques. The extension is then demonstrated using datasets from previous publications on …

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Passive Phase Separation Of Microgravity Bubbly Flows Using Conduit Geometry, Ryan M. Jenson, Andrew Paul Wollman, Mark M. Weislogel, Lauren Sharp, Robert Green, Peter J. Canfield, Jörg Klatte, Michael E. Dreyer Oct 2014

Passive Phase Separation Of Microgravity Bubbly Flows Using Conduit Geometry, Ryan M. Jenson, Andrew Paul Wollman, Mark M. Weislogel, Lauren Sharp, Robert Green, Peter J. Canfield, Jörg Klatte, Michael E. Dreyer

Mechanical and Materials Engineering Faculty Publications and Presentations

The ability to separate liquid and gas phases in the absence of a gravitational acceleration has proven a challenge to engineers since the inception of space exploration. Due to our singular experience with terrestrial systems, artificial body forces are often imparted in multiphase fluid systems aboard spacecraft to reproduce the buoyancy effect. This approach tends to be inefficient, adding complexity, resources, and failure modes. Ever present in multiphase phenomena, the forces of surface tension can be exploited to aid passive phase separations where performance characteristics are determined solely by geometric design and system wettability. Said systems may be readily designed …

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The Effect Of Multi-Model Averaging Of Climate Model Outputs On The Seasonality Of Rainfall Over The Columbia River Basin, Mehmet Demirel, Arun Rana, Hamid Moradkhani Sep 2014

The Effect Of Multi-Model Averaging Of Climate Model Outputs On The Seasonality Of Rainfall Over The Columbia River Basin, Mehmet Demirel, Arun Rana, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

The rainfall seasonality index is the measure of precipitation distribution throughout the seasonal cycle. The aim of this study is to compare the effect of different multi-model averaging methods on the rainfall seasonality index at each 1/16 latitude-longitude cells covering the Columbia River Basin. In accordance with the same, ten different climate model outputs are selected from 45 available climate models from CMIP5 dataset. The reanalysis precipitation data is used to estimate the errors in rainfall seasonality for the climate model outputs. The inverse variance method and statistical multi criteria analysis (SMCA) method were used to estimate the weights for …

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Secondary Organic Aerosol Formation And Organic Nitrate Yield From No3 Oxidation Of Biogenic Hydrocarbons, Juliane L. Fry, Danielle C. Draper, Kelley C. Barsanti, James N. Smith, John Ortega, Paul M. Winkler, Michael J. Lawler, Steven S. Brown, Peter M. Edwards, Ronald C. Cohen, Lance Lee Sep 2014

Secondary Organic Aerosol Formation And Organic Nitrate Yield From No3 Oxidation Of Biogenic Hydrocarbons, Juliane L. Fry, Danielle C. Draper, Kelley C. Barsanti, James N. Smith, John Ortega, Paul M. Winkler, Michael J. Lawler, Steven S. Brown, Peter M. Edwards, Ronald C. Cohen, Lance Lee

Civil and Environmental Engineering Faculty Publications and Presentations

The secondary organic aerosol (SOA) mass yields from NO3 oxidation of a series of biogenic volatile organic compounds (BVOCs), consisting of five monoterpenes and one sesquiterpene (α-pinene, β-pinene, Δ-3-carene, limonene, sabinene, and β-caryophyllene), were investigated in a series of continuous flow experiments in a 10 m3 indoor Teflon chamber. By making in situ measurements of the nitrate radical and employing a kinetics box model, we generate time-dependent yield curves as a function of reacted BVOC. SOA yields varied dramatically among the different BVOCs, from zero for α-pinene to 38−65% for Δ-3-carene and 86% for β-caryophyllene at mass loading of 10 …

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Impacts Of Climate Change On The Seasonality Of Extremes In The Columbia River Basin, Mehmet Demirel, Hamid Moradkhani Sep 2014

Impacts Of Climate Change On The Seasonality Of Extremes In The Columbia River Basin, Mehmet Demirel, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

The impacts of climate change on the seasonality of extremes i.e. both high and low flows in the Columbia River basin were analyzed using three seasonality indices, namely the seasonality ratio (SR), weighted mean occurrence day (WMOD) and weighted persistence (WP). These indices reflect the streamflow regime, timing and variability in timing of extreme events respectively. The three indices were estimated from: (1) observed streamflow; (2) simulated streamflow by the VIC model using simulated inputs from ten combinations of bias corrected and downscaled CMIP5 inputs for the current climate (1979–2005); (3) simulated streamflow using simulated inputs from ten combinations of …

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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.

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Can Tidal Perturbations Associated With Sea Level Variations In The Western Pacific Ocean Be Used To Understand Future Effects Of Tidal Evolution?, Adam T. Devlin, David A. Jay, Stefan A. Talke, Edward D. Zaron Aug 2014

Can Tidal Perturbations Associated With Sea Level Variations In The Western Pacific Ocean Be Used To Understand Future Effects Of Tidal Evolution?, Adam T. Devlin, David A. Jay, Stefan A. Talke, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

This study examines connections between mean sea level (MSL) variability and diurnal and semidiurnal tidal constituent variations at 17 open-ocean and 9 continental shelf tide gauges in the western tropical Pacific Ocean, a region showing anomalous rise in MSL over the last 20 years and strong interannual variability. Detrended MSL fluctuations are correlated with detrended tidal amplitude and phase fluctuations, defined as tidal anomaly trends (TATs), to quantify the response of tidal properties to MSL variation. About 20 significant amplitude and phase TATs are found for each of the two strongest tidal constituents, K1 (diurnal) and M2 (semidiurnal). …

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Modeling And Analyzing The Impact Of Advanced Technologies On Transit Performance Measures In Arterial Corridors, Miguel A. Figliozzi, Wei Feng Aug 2014

Modeling And Analyzing The Impact Of Advanced Technologies On Transit Performance Measures In Arterial Corridors, Miguel A. Figliozzi, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

Transportation and transit agencies have implemented advanced technologies like transit signal priority (TSP) and Sydney Coordinated Adaptive Traffic System (SCATS) to reduce travel times and improve reliability. However, due to the lack of detailed empirical data, the joint impact of these factors and improvement strategies on bus travel time has not been studied at the stop-to-stop segment level. With the aim of assessing the performance of an existing TSP/SCATS system, this study had access to a unique set of high-resolution bus and traffic signal data. Novel algorithms and performance measures to measure TSP performance are proposed. Results indicate that a …

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Coel: A Web-Based Chemistry Simulation Framework, Peter Banda, Drew Blount, Christof Teuscher Jul 2014

Coel: A Web-Based Chemistry Simulation Framework, Peter Banda, Drew Blount, Christof Teuscher

Computer Science Faculty Publications and Presentations

The chemical reaction network (CRN) is a widely used formalism to describe macroscopic behavior of chemical systems. Available tools for CRN modelling and simulation require local access, installation, and often involve local file storage, which is susceptible to loss, lacks searchable structure, and does not support concurrency. Furthermore, simulations are often single-threaded, and user interfaces are non-trivial to use. Therefore there are significant hurdles to conducting efficient and collaborative chemical research. In this paper, we introduce a new enterprise chemistry simulation framework, COEL, which addresses these issues. COEL is the first web-based framework of its kind. A visually pleasing and …

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Tillamook County Waste Disposal Technology Assessment, Arvind Kumar, Ryan Menze, Joe Smith, Jerrod Thomas Jul 2014

Tillamook County Waste Disposal Technology Assessment, Arvind Kumar, Ryan Menze, Joe Smith, Jerrod Thomas

Engineering and Technology Management Student Projects

Tillamook County is a rural county straddling the Northern Oregon Coast Range with the majority of the local economy based around agriculture, timber, tourism, and fishing. As part of Tillamook County’s mission statement, they strive“to enhance the quality of life for its citizens by promoting and preserving public health and safety, maintaining a stable economy, encouraging wise use of resources, and providing services in the most efficient and cost-effective manner possible.” To that end, Tillamook County, Tillamook County Economic Development Council (TCEDC), Portland State University, Oregon State University, and Tetra Tech have undergone an evaluation and technology assessment process to …

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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 …

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An Analysis Of Secular Change In Tides At Open-Ocean Sites In The Pacific, Edward D. Zaron, David A. Jay Jul 2014

An Analysis Of Secular Change In Tides At Open-Ocean Sites In The Pacific, Edward D. Zaron, David A. Jay

Civil and Environmental Engineering Faculty Publications and Presentations

Hourly sea level is examined at 25 open-ocean stations in the Pacific Ocean with records longer than 30 yr. A search for trends finds that the amplitude of the dominant semidiurnal tide M2 is increasing at 12 of the 13 sites where a statistically significant trend can be identified. It is also found that nontidal variance in the neighborhood of M2 is decreasing at all 12 of the sites where a significant increase in M2 tide is occurring. The trend in amplitude of the dominant diurnal tide K1 is significant at six stations, and it is …

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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 …

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Toward A Reliable Prediction Of Seasonal Forecast Uncertainty: Addressing Model And Initial Condition Uncertainty With Ensemble Data Assimilation And Sequential Bayesian Combination, Caleb Matthew Dechant, Hamid Moradkhani Jun 2014

Toward A Reliable Prediction Of Seasonal Forecast Uncertainty: Addressing Model And Initial Condition Uncertainty With Ensemble Data Assimilation And Sequential Bayesian Combination, Caleb Matthew Dechant, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

Uncertainties are an unfortunate yet inevitable part of any forecasting system. Within the context of seasonal hydrologic predictions, these uncertainties can be attributed to three causes: imperfect characterization of initial conditions, an incomplete knowledge of future climate and errors within computational models. This study proposes a method to account for all threes sources of uncertainty, providing a framework to reduce uncertainty and accurately convey persistent predictive uncertainty. In currently available forecast products, only a partial accounting of uncertainty is performed, with the focus primarily on meteorological forcing. For example, the Ensemble Streamflow Prediction (ESP) technique uses meteorological climatology to estimate …

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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.

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Durability Assessment Of Recycled Concrete Aggregates For Use In New Concrete Phase Ii, Jason H. Ideker, Matthew P. Adams, Jennifer Tanner, Angela Jones Jun 2014

Durability Assessment Of Recycled Concrete Aggregates For Use In New Concrete Phase Ii, Jason H. Ideker, Matthew P. Adams, Jennifer Tanner, Angela Jones

TREC Final Reports

This Phase II investigation into the durability of new concrete incorporating recycled concrete aggregates (RCA) focused on several goals: 1) Provide corroboration of results obtained in Phase I for a multi-laboratory study related to assessing alkali-silica reactivity (ASR) of RCA in accelerated laboratory tests; 2) Investigate the efficacy of mitigation methods to control ASR in concrete containing potentially reactive RCA; 3) Establish long-term data through placement of concrete blocks containing RCA in an outdoor exposure site in Laramie, WY; and 4) Survey state DOTs and other transportation agencies about their perceptions and usage of RCA ASR in concrete within their …

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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 …

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Local Vibrational Modes Competitions In Mn-Doped Zno Epitaxial Films With Tunable Ferromagnetism, Qiang Cao, Maoxiang Fu, Guolei Liu, Huaijin Zhang, Shishen Yan, Yanxue Chen, Liangmo Mei, Jun Jiao Jun 2014

Local Vibrational Modes Competitions In Mn-Doped Zno Epitaxial Films With Tunable Ferromagnetism, Qiang Cao, Maoxiang Fu, Guolei Liu, Huaijin Zhang, Shishen Yan, Yanxue Chen, Liangmo Mei, Jun Jiao

Mechanical and Materials Engineering Faculty Publications and Presentations

We reported spectroscopic investigations of high quality Mn-doped ZnO (ZnMnO) films grown by oxygen plasma-assisted molecular beam epitaxy. Raman scattering spectra revealed two local vibrational modes (LVMs) associated with Mn dopants at 523 and 712cm-1. The LVMs and magnetic properties of ZnMnO films can be synchronously modulated by post annealing processing or by introducing tiny Co. The relative intensity of two LVMs clearly shows competitions arising from uncompensated acceptor and donor defects competition for ferromagnetic and nonmagnetic films. The experimental results indicated that LVM at 523 cm-1 is attributed to Mn—(Zinc-vacancy) complexes, while LVM at 712 cm …

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Wake Interaction And Power Production Of Variable Height Model Wind Farms, M. H. Vested, N. Hamilton, J. N. Sørensen, Raul Bayoan Cal Jun 2014

Wake Interaction And Power Production Of Variable Height Model Wind Farms, M. H. Vested, N. Hamilton, J. N. Sørensen, Raul Bayoan Cal

Mechanical and Materials Engineering Faculty Publications and Presentations

Understanding wake dynamics is an ongoing research topic in wind energy, since wakes have considerable effects on the power production when wind turbines are placed in a wind farm. Wind tunnel experiments have been conducted to study the wake to wake interaction in a model wind farm in tandem with measurements of the extracted power. The aim is to investigate how alternating mast height influences the interaction of the wakes and the power production. Via the use of stereo-particle image velocimetry, the flow field was obtained in the first and last rows of the wind turbine array as a basis …

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Design And Implementation Of Pedestrian And Bicycle-Specific Data Collection Methods In Oregon, Miguel Figliozzi, Christopher Monsere, Krista Nordback, Pamela Johnson, Bryan Philip Blanc Jun 2014

Design And Implementation Of Pedestrian And Bicycle-Specific Data Collection Methods In Oregon, Miguel Figliozzi, Christopher Monsere, Krista Nordback, Pamela Johnson, Bryan Philip Blanc

Civil and Environmental Engineering Faculty Publications and Presentations

Although there is a growing need to access accurate and reliable pedestrian and bicycle data, there is no statewide system to collect data or plan future data collection efforts in the state of Oregon. To address these issues this research conducted a comprehensive review of pedestrian and bicycle data collection methods and counting technologies. Oregon data sources were also compiled and AADT estimation techniques were reviewed and applied to Oregon data. A pilot study was conducted to test bicycle and pedestrian counting methods at signalized intersections with 2070 controllers. The report also provides a summary of recommendations regarding factoring methods …

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Lessons From The Green Lanes: Evaluating Protected Bike Lanes In The U.S., Christopher Monsere, Jennifer Dill, Nathan Mcneil, Kelly J. Clifton, Nick Foster, Tara Goddard, Mathew Berkow, Joe Gilpin, Kim Voros, Drusilla Van Hengel, Jamie Parks Jun 2014

Lessons From The Green Lanes: Evaluating Protected Bike Lanes In The U.S., Christopher Monsere, Jennifer Dill, Nathan Mcneil, Kelly J. Clifton, Nick Foster, Tara Goddard, Mathew Berkow, Joe Gilpin, Kim Voros, Drusilla Van Hengel, Jamie Parks

Civil and Environmental Engineering Faculty Publications and Presentations

This report presents finding from research evaluating U.S. protected bicycle lanes (cycle tracks) in terms of their use, perception, benefits, and impacts. This research examines protected bicycle lanes in five cities: Austin, TX; Chicago, IL; Portland, OR; San Francisco, CA; and Washington, D.C., using video, surveys of intercepted bicyclists and nearby residents, and count data. A total of 168 hours were analyzed in this report where 16,393 bicyclists and 19,724 turning and merging vehicles were observed. These data were analyzed to assess actual behavior of bicyclists and motor vehicle drivers to determine how well each user type understands the design …

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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.

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