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Transport Of Heat Activated Persulfate And Its Application For In-Situ Chemical Oxidation Of Residual Trichloroethylene, Lauren Dekker Quig Nov 2015

Transport Of Heat Activated Persulfate And Its Application For In-Situ Chemical Oxidation Of Residual Trichloroethylene, Lauren Dekker Quig

Dissertations and Theses

In situ chemical oxidation is a promising technology for the remediation of persistent subsurface contamination. Increasingly, the persulfate ion is being studied for use in these systems, both on its own as a strong oxidant and as the precursor to the even more reactive sulfate radical. Persulfate has been shown to treat a wide range of contaminants, from traditional Superfund contaminants such as chlorinated solvents to emerging pharmaceutical contaminants. Additionally, persulfate ISCO can be tailored to site and pollutant specific characteristics based on the method of persulfate activation (e.g., energy and catalysis activation) to the sulfate radical. Thermal activation of …


An Exploration Of Bicyclist Comfort Levels Utilizing Crowdsourced Data, Bryan Philip Blanc Sep 2015

An Exploration Of Bicyclist Comfort Levels Utilizing Crowdsourced Data, Bryan Philip Blanc

Dissertations and Theses

Bicycle transportation has become a central priority of urban areas invested in improving sustainability, livability, and public health outcomes. Transportation agencies are striving to increase the comfort of their bicycle networks to improve the experience of existing cyclists and to attract new cyclists. The Oregon Department of Transportation sponsored the development of ORcycle, a smartphone application designed to collect cyclist travel, comfort, and safety information throughout Oregon. The sample resulting from the initial deployment of the application between November 2014 and March 2015 is described and analyzed within this thesis. 616 bicycle trips from 148 unique users were geo-matched to …


A Multivariate Modeling Approach For Generating Ensemble Climatology Forcing For Hydrologic Applications, Sepideh Khajehei Jul 2015

A Multivariate Modeling Approach For Generating Ensemble Climatology Forcing For Hydrologic Applications, Sepideh Khajehei

Dissertations and Theses

Reliability and accuracy of the forcing data plays a vital role in the Hydrological Streamflow Prediction. Reliability of the forcing data leads to accurate predictions and ultimately reduction of uncertainty. Currently, Numerical Weather Prediction (NWP) models are developing ensemble forecasts for various temporal and spatial scales. However, it is proven that the raw products of the NWP models may be biased at the basin scale; unlike model grid scale, depending on the size of the catchment. Due to the large space-time variability of precipitation, bias-correcting the ensemble forecasts has proven to be a challenging task. In recent years, Ensemble Pre-Processing …


Evaluating Global Sensitivity Analysis Methods For Hydrologic Modeling Over The Columbia River Basin, Maysoun Ayad Hameed Jul 2015

Evaluating Global Sensitivity Analysis Methods For Hydrologic Modeling Over The Columbia River Basin, Maysoun Ayad Hameed

Dissertations and Theses

Global Sensitivity Analysis (GSA) approach helps to identify the effectiveness of model parameters or inputs and thus provides essential information about the model performance. The effects of 14 parameters and one input (forcing data) of the Sacramento Soil Moisture Accounting (SAC-SMA) model are analyzed by using two GSA methods: Sobol' and Fourier Amplitude Sensitivity Test (FAST). The simulations are carried out over five sub-basins within the Columbia River Basin (CRB) for three different periods: one-year, four-year, and seven-year. The main parameter sensitivities (first-order) and the interactions sensitivities (second-order) are evaluated in this study. Our results show that some hydrological processes …


An Evaluation Of The Neighborhood Traffic Management Program Of Centennial, Colorado, Rolando Gabriel Melgoza Jul 2015

An Evaluation Of The Neighborhood Traffic Management Program Of Centennial, Colorado, Rolando Gabriel Melgoza

Civil and Environmental Engineering Master's Project Reports

Residential neighborhoods throughout the United States seek to maintain a quality of life where residents can live free of traffic factors adversely affecting their safety. Many communities have adopted a Neighborhood Traffic Management Program (NTMP) to address concerns over cut-through traffic, speeding, and safety. The City of Centennial, Colorado, incorporated in 2001, is a young city and has its own NTMP. Four traffic mitigation projects have been implemented. The objective of this research is to conduct a before and after comparison study of each Centennial NTMP project, to review the NTMP policies of American cities with similar suburban characteristics to …


Experimental Investigation Of Fiber Reinforced Concrete Beams, Karrar Ali Al-Lami Jun 2015

Experimental Investigation Of Fiber Reinforced Concrete Beams, Karrar Ali Al-Lami

Dissertations and Theses

Shear strength of fiber reinforced concrete beams was studied in this research project. Three types of fibers were examined: hooked-end steel fiber, crimped-steel fiber, and crimped-monofilament polypropylene fibers. The experimental program included five beam specimens. Two of the beams were control specimens in which one was reinforced with minimum shear reinforcement according to ACI 318, while the other one did not have any shear reinforcement. Each one of the other three specimens was reinforced with one of the above mentioned fibers by 1% volumetric ratio. In addition to the beam specimens, three prisms were also made for each type fiber …


Climate Change Assessment In Columbia River Basin (Crb) Using Copula Based On Coupling Of Temperature And Precipitation, Yueyue Qin May 2015

Climate Change Assessment In Columbia River Basin (Crb) Using Copula Based On Coupling Of Temperature And Precipitation, Yueyue Qin

Dissertations and Theses

The multi downscaled-scenario products allow us to better assess the uncertainty of the variations of precipitation and temperature in the current and future periods. Joint Probability distribution functions (PDFs), of both the climatic variables, might help better understand the interdependence of the two, and thus in-turn help in accessing the future with confidence. In the present study, we have used multi-modelled statistically downscaled ensemble of precipitation and temperature variables. The dataset used is multi-model ensemble of 10 Global Climate Models (GCMs) downscaled product from CMIP5 daily dataset, using the Bias Correction and Spatial Downscaling (BCSD) technique, generated at Portland State …


Behavior Of Reinforced Concrete Beams Retrofitted In Flexure Using Cfrp-Nsm Technique, Salam Al-Obaidi May 2015

Behavior Of Reinforced Concrete Beams Retrofitted In Flexure Using Cfrp-Nsm Technique, Salam Al-Obaidi

Dissertations and Theses

A variety of retrofitting methods are used to upgrade existing structures. For example, steel plates and Fiber Reinforced Polymer (FRP) jackets are externally bonded to members to increase their capacity in flexure and shear. However, due to the issue of corrosion these strengthening systems may lose their efficiency with time. FRP materials have been used to strengthen many structural components of different shapes and types. FRP jackets, FRP Strips, and FRP rods have commonly been used to rehabilitate existing structural components. The many advantages of using FRP as strengthening materials have made this material an attractive alternative: advantages such as …


Evaluating The Effects Of A Congestion And Weather Responsive Advisory Variable Speed Limit System In Portland, Oregon, Matthew Blake Downey May 2015

Evaluating The Effects Of A Congestion And Weather Responsive Advisory Variable Speed Limit System In Portland, Oregon, Matthew Blake Downey

Dissertations and Theses

Safety and congestion are ever present and increasingly severe transportation problems in urban areas throughout the nation and world. These phenomena can have wide-ranging consequences relating to safety, the economy, and the environment. Adverse weather conditions represent another significant challenge to safety and mobility on highways. Oregon is not immune from either of these global issues. Oregon Route (OR) 217, to the southwest of the downtown Portland, is one of the worst freeways for congestion in the state and is also subject to the Pacific Northwest's frequently inclement and unpredictable climate. High crash rates, severe recurrent bottlenecks and highly unreliable …


Bicyclist Compliance At Signalized Intersections, Samson Ray Riley Thompson Mar 2015

Bicyclist Compliance At Signalized Intersections, Samson Ray Riley Thompson

Dissertations and Theses

This project examined cyclist red light running behavior using two data sets. Previous studies of cyclist compliance have investigated the tendencies of cyclists to run red lights on the whole by generalizing different maneuvers to their end outcome, running a red light. This project differentiates between the different types of red light running and focuses on the most egregious case, gap acceptance, which is when a cyclist runs a red light by accepting a gap in opposing traffic.

Using video data, a mathematical model of cyclist red light running was developed for gap acceptance. Similar to other studies, this analysis …


Impacts Of Replacing A Tight Diamond Interchange With A Spui – A Wilsonville Interchange Study, Sina Vadaei Mar 2015

Impacts Of Replacing A Tight Diamond Interchange With A Spui – A Wilsonville Interchange Study, Sina Vadaei

Civil and Environmental Engineering Master's Project Reports

Tight diamond interchanges (TDI) and single point urban interchanges (SPUIs) are generally types of interchanges that can be used interchangeably in areas where right-of-way is constrained. There are limited amount of research conducted regarding the operational analysis and comparison of these two interchanges. The research that has been done regarding this topic are outdated and generally conclude that SPUIs perform better or about the same. Without knowing the true performances of the two interchange designs, it would make it difficult for engineers and planners to choose between the two interchanges.

This research study will use the current updated version of …


On The Estimation Of Volumes Of Roadways: An Investigation Of Stop-Controlled Minor Legs, Joel Stephen Barnett Feb 2015

On The Estimation Of Volumes Of Roadways: An Investigation Of Stop-Controlled Minor Legs, Joel Stephen Barnett

Dissertations and Theses

This effort seeks to answer the question; can a transferable model be developed from easily obtainable, publicly available land-use, census, roadway, and network data for the use in safety performance functions? 474 stop-controlled minor legs were used as the training data set using ordinary least squares regression. A best-fit model of maximum independent variables, n=12 was chosen using an exhaustive approach using Mallow's Cp to select the model with least bias in the predictors. The results of the analysis revealed that the combination of variables from Washington, Ohio, and North Carolina did not have a strong relationship. The best-fit model …


Safety At Half-Signal Intersections In Portland, Oregon, Todd Robert Johnson Feb 2015

Safety At Half-Signal Intersections In Portland, Oregon, Todd Robert Johnson

Dissertations and Theses

The safety at half-signalized intersections in Portland, Oregon is analyzed in this thesis using 10 years of crash history and analysis of video that was collected at a subset of intersections. A half-signalized intersection has a standard red-yellow-green traffic signal for automobiles on the major road, a stop sign for motorists on the minor road, and a pedestrian signal with actuation for pedestrians and/or bicyclists on the minor road. Although prevalent in Canada, this type of intersection control is not typically found in the United States because the MUTCD explicitly prohibits its use. Half-signal use is limited mostly to two …


A Microsimulation Of Novel Intersection Designs, Aman Kinfemichael Woldetinsae Jan 2015

A Microsimulation Of Novel Intersection Designs, Aman Kinfemichael Woldetinsae

Civil and Environmental Engineering Master's Project Reports

The focus of this project is to see how a turbo roundabout and a protected intersection designs behave when they are applied on two study sites in Portland, OR. PTV VISSM is used to model, analyze and compare the performances of these designs with the existing intersection. In addition, the best features of the protected intersection and the turbo roundabout were combined to create a new intersection design that is safer for the bicyclists and also performs better than the existing intersection.

The analysis is conducted for five different volume scenarios for both the study sites. The results of the …


Analyzing Free-Base Nicotine Content In The Particulate Matter Of Mainstream Tobacco Smoke Using A Headpace Solid-Phase Microextraction Gc/Ms Method, Christopher S. Motti Jan 2015

Analyzing Free-Base Nicotine Content In The Particulate Matter Of Mainstream Tobacco Smoke Using A Headpace Solid-Phase Microextraction Gc/Ms Method, Christopher S. Motti

Civil and Environmental Engineering Master's Project Reports

The acid/base chemistry of cigarette smoke allows nicotine, the primary drug in mainstream tobacco smoke, to exist in protonated and free-base forms. Evidence suggests that most of the nicotine present in mainstream tobacco smoke is in the particle phase. αfb is the fraction of particle-phase nicotine in the free-base form. The magnitude and rate of nicotine deposition in the respiratory tract is dependent on αfb because only the free-base form of nicotine can volatilize from the particle phase of an inhaled aerosol and, once gaseous, rapidly deposit. This study develops a headspace solid-phase microextraction technique coupled with gas …


Key Aspects For Lrfd Implementation For Driven Pile Capacity By Dynamic Methods, Natalie R. Ehrlich Jan 2015

Key Aspects For Lrfd Implementation For Driven Pile Capacity By Dynamic Methods, Natalie R. Ehrlich

Civil and Environmental Engineering Master's Project Reports

Inputs and interpretation procedures for pile wave equation analysis, which correlates measured field dynamic driving response to axial pile static capacity, are highly dependent on site-specific soil conditions and field practices. The 6th Edition of the AASHTO LRFD Bridge Design Specifications provide generalized guidelines for pile design, but do not account for variability in region-specific soils and field practices. A comprehensive literature review of region-specific resistance factor recalibration efforts across the U.S. has given insight into the range of implementation issues encountered, especially the key decisions around choosing a restrike (BOR), along with measures of efficiency and treatment of …


Geotechnical Statistical Evaluation Of Lahore Site Data And Deep Excavation Design, Aiza Malik Jan 2015

Geotechnical Statistical Evaluation Of Lahore Site Data And Deep Excavation Design, Aiza Malik

Civil and Environmental Engineering Master's Project Reports

Geotechnical characterization for foundation design is critical during preliminary planning, designing and feasibility studies of various engineering projects. In this research, an effort has been made to develop a geotechnical database for the city of Lahore, Pakistan. This database would aid geologists and engineers involved in the geotechnical design and planning of engineering projects in Lahore. The project area has been divided into zones geographically. Soil profiles have been developed for all zones, which provide ranges of soil properties and SPT-N values at regular intervals. Furthermore, the research also focuses on deep excavations in urban areas of Lahore, Pakistan and …


Pushover Analysis Of Retrofitted Reinforced Concrete Buildings, Hamidreza Nahavandi Jan 2015

Pushover Analysis Of Retrofitted Reinforced Concrete Buildings, Hamidreza Nahavandi

Civil and Environmental Engineering Master's Project Reports

For the past decade or more, the structural engineering profession has been using the nonlinear static procedure (NSP) or pushover analysis. Modeling for such analysis requires the determination of nonlinear properties of each component in the structure, quantified by strength and deformation capacities, which depend on the modeling assumptions. Pushover analysis is carried out for either user-defined nonlinear hinge properties or default-hinge properties, available in some programs based on the FEMA-356 such as SAP2000. While such documents provide the hinge properties for several ranges of detailing, programs may implement averaged values. In the realm of retrofitting of existing structures, few …


Geostatistical Examination Of The Geotechnical Portland Bes Databases With Emphasis On Silt, Alex K. Baumann Jan 2015

Geostatistical Examination Of The Geotechnical Portland Bes Databases With Emphasis On Silt, Alex K. Baumann

Civil and Environmental Engineering Master's Project Reports

Willamette Valley silt deposits from historical catastrophic flood events present a difficult problem for subsurface engineers practicing in the Portland, Oregon area. Silts exhibit behavior of two very well-documented soil types, but publications containing mechanical properties for silts are scant, especially for local silts. Thus, the need for links between real Portland site investigation data and silt properties is high. To further exemplify the need for documented knowledge of local silts, this project reveals the evolving state of practice to incorporate more Pacific Northwest seismic analyses in preparation for a subduction zone earthquake. The geotechnical Portland BES databases contain thousands …


Dispersion Modeling Of Nitrogen Dioxide (No2) And Fine Particulate Matter (Pm2.5) From Backup Generators At Data Centers In Prineville, Oregon, Brooke E. Harmon Jan 2015

Dispersion Modeling Of Nitrogen Dioxide (No2) And Fine Particulate Matter (Pm2.5) From Backup Generators At Data Centers In Prineville, Oregon, Brooke E. Harmon

Civil and Environmental Engineering Master's Project Reports

As our society becomes increasingly dependent on digital communication (e.g., social media and email) and computerized storage (e.g., digitized medical records and government documents), tech giants such as Google, Facebook, and Apple are constructing and managing an increasing number of massive Internet data centers. These data centers house a network’s most critical systems and are vital to the continuity of daily operations. Requiring as much electricity as a medium size city, data centers rely on complex auxiliary power systems to prevent disruption to service. These backup systems consist of tens of multi-megawatt diesel-powered generators that release combustion byproducts, including over …


Parametric Study Of Rocking Shallow Foundations Under Seismic Excitation, Benjamin I. Herdrich Jan 2015

Parametric Study Of Rocking Shallow Foundations Under Seismic Excitation, Benjamin I. Herdrich

Civil and Environmental Engineering Master's Project Reports

Conventional design of structures relies on incorporating a certain level of inelastic deformation into select components to provide seismic energy dissipation, while ensuring the foundation remains relatively stationary. However, this inelasticity comes at the cost of severe damage to the structure, which often is no longer suitable to occupancy after a seismic event. In contrast with conventional structures, structures with rocking foundations shift the ductility demands away from the structure itself, and onto the underlying soil, which may result in less damage and greater stability. The purpose of this study is to explore the behavior and performance of a simple …


Comparing Mode Shares For Non-Residential Destinations In Urban And Suburban Environments, Tasnia Subrin Jan 2015

Comparing Mode Shares For Non-Residential Destinations In Urban And Suburban Environments, Tasnia Subrin

Civil and Environmental Engineering Master's Project Reports

To ensure facility for multimodal transportation is one of the most important concerns in today's transportation sector, with initiatives being taken to make multimodal transportation popular. The built environment variables have a strong relationship with transportation mode choice, but whether that relationship holds true in urban and suburban neighborhoods in the same manner has not been considered. Using data for three non-residential land uses, this research explores whether the built environment variables in suburban areas influences mode share like it does in urban areas. We used survey data conducted at the establishments regarding respondents' travel characteristics from a previous study, …


Dynamic Effect Of Light And Turbulence On Algal Photosynthetic Rate: A Water-Quality Model, Andres R. Rivas Jan 2015

Dynamic Effect Of Light And Turbulence On Algal Photosynthetic Rate: A Water-Quality Model, Andres R. Rivas

Civil and Environmental Engineering Master's Project Reports

Several studies provide evidence that algal photosynthetic rates depend on various changing factors such as light attenuation, temperature, and nutrient limitation (Chapra, 1997). However, recent papers show that turbulence and photosynthetic rate dynamics is also important (Ross, 2006). In this study, the photosynthetic rate model used is the one proposed by Chapra (1997), where it depends directly on temperature, nutrient and light limitation factors. At the same time, the effect of turbulence or random-walk of algae particles in the water column was also introduced in this model. To account for this factor, the model added was that proposed by Ross …


Safety At Intersections In Oregon: A Preliminary Update Of Statewide Intersection Crash Rates, Daniel R. Hazel Jan 2015

Safety At Intersections In Oregon: A Preliminary Update Of Statewide Intersection Crash Rates, Daniel R. Hazel

Civil and Environmental Engineering Master's Project Reports

This research aims to provide a preliminary update to statewide intersection crash rates for the state of Oregon using 2008-2013 crash data and a statewide sample of 129 intersections where two (or more) state-owned facilities intersect. Using intersections where state-owned facilities represent both the major and minor legs of the intersection allows for the maintenance of up-to-date intersection crash rates by eliminating time-intensive traffic volume data collection. Due to the frequency and severity of crashes at intersections, development of easily obtained intersection crash rates is important to assess trends and effectiveness of safety countermeasures employed at these locations in the …