Engineering Commons^™

A Study Of Headway Maintenance For Bus Routes: Causes And Effects Of “Bus Bunching” In Extensive And Congested Service Areas, Miguel A. Figliozzi, Wu-Chi Feng, Gerardo Lafferriere, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

A healthy and efficient public transit system is indispensable to reduce congestion, emissions, energy consumption, and car dependency in urban areas. The objective of this research is to 1) develop methods to evaluate and visualize bus service reliability for transit agencies in various temporal and spatial aggregation levels; 2) identify the recurrent unreliability trends of bus routes (focusing on high-frequency service periods) and understand their characteristics, causes and effects; and 3) model service times using linear regression models.

This research utilized six months of archived automatic vehicle location (AVL) and automatic passenger count (APC) data from a low-performance route (Route …

Analyzing And Quantifying The Impact Of Congestion On Ltl Industry Costs And Performance In The Portland Metropolitan Region, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Increased congestion during peak morning and afternoon periods in urban areas is increasing logistics costs. In addition, environmental, social, and political pressures to limit the impacts associated with CO2 emissions are mounting rapidly. A key challenge for transportation agencies and businesses is to improve the efficiency of urban freight and commercial vehicle movements while ensuring environmental quality, livable communities, and economic growth. However, research and policy efforts to analyze and quantify the impacts of congestion and freight public policies on carriers operations and CO2 emissions are hindered by the complexities of vehicle routing problems with time-dependent travel times and the …

Capillarity-Driven Droplet Ejection, Andrew Paul Wollman

Dissertations and Theses

Drop Towers provide brief terrestrial access to microgravity environments. When used for capillary fluidics research, a drop tower allows for unique control over an experiment's initial conditions, which enables, enhances, or otherwise improves the study of capillary phenomena at significantly larger length scales than can normally be achieved on the ground. This thesis provides a historical context for the introduction of a new, highly accessible, 2.1s tower design used for capillary research and presents a variety of demonstrative experimental results for purely capillarity-driven flows leading to bubble ingestion, sinking flows, multiphase flows, and droplet ejections. The focus of this thesis …

Seismic Hazard Assessment Of Oregon Highway Truck Routes, Peter Dusicka, Selamawit Tesfayesus Mehary

TREC Final Reports

This research project developed a seismic risk assessment model along the major truck routes in Oregon. The study had adopted federally developed software tools called Risk for Earthquake Damage to Roadway Systems (REDARS2) and HAZUS-MH. The model was the first time REDARS2 has been adopted and used in research outside of the original development team, presenting a number of unique challenges. The development of the model was a complex, intensive process that required a significant research effort, manipulation and adjustment of data. Furthermore, limitations of the software tools themselves had been identified that prevented the inclusion of important aspects such …

An Empirical Study Of Particulate Matter Exposure For Passengers Waiting At Bus Stop Shelters In Portland, Oregon, Usa, Adam Moore, Miguel A. Figliozzi, Christopher Michael Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

Current guidelines for the location and design of bus stops do not take into account air quality or exposure considerations for waiting passengers. This paper compares the exposure of transit riders waiting at three-sided bus stop shelters that either: 1) face roadway traffic, or 2) face away from roadway traffic. Shelters were instrumented with devices to monitor particulate matter concentration inside and outside the shelter, wind speed and direction, and vehicle counts. Data were collected at three shelters during both the morning and afternoon peak periods. Bus shelter orientation is found to have a significant effect on the concentration of …

Regional Models Of Internal Tides, Glenn S. Carter, Oliver B. Fringer, Edward D. Zaron

Civil and Environmental Engineering Faculty Publications and Presentations

Internal tides are ubiquitous in the ocean, and they play an important role in a range of ocean processes, for example, particle dispersal, acoustics, and vertical buoyancy flux. The wavelength of internal tides can be as much as 250 km in the open ocean, but as the generation of these tides depends on the angle between the depth-averaged current and the topography, there can be considerable local spatial variability. This range of scales makes it difficult to develop a comprehensive understanding of the processes involved from observations alone. Regional numerical modeling provides a way to study the generation and early …

Analysis Of The Impacts Of Transit Signal Priority On Bus Bunching And Performance, Eric Albright, Miguel Andres Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Efficient and reliable public transit systems provide opportunities to reduce congestion, emissions in urban areas and provide access and mobility to residents. Headway, or the time difference between departing or arriving vehicles, is a useful measure to gauge bus transit performance; because short headways can lead to bus bunching incidents that quickly degrade transit level of service. While Transit Signal Priority (TSP) has been shown to decrease travel time and delay experienced by buses, little work has shown how TSP may affect bus bunching. This research attempts to understand the characteristics of bus trips, especially TSP, that prevent or promote …

An Evaluation Of The Impacts Of An Adaptive Coordinated Traffic Signal System On Transit Performance: A Case Study On Powell Boulevard (Portland, Oregon), Courtney Natasha Slavin, Miguel A. Figliozzi, Wei Feng

Civil and Environmental Engineering Faculty Publications and Presentations

Powell Boulevard is a prime example of a congested urban arterial; this roadway connects US-26 to downtown Portland, Oregon. This facility is one of the most congested arterial corridors in the Portland-metropolitan region. The City of Portland implemented the Sydney Coordinated Adaptive Traffic System (SCATS) in October 2011 in order to improve the operations of the corridor. SCATS has been implemented in a few US cities with mixed results so far. A properly calibrated system can have a significant positive impact on the performance of the traffic signals but its impact on transit performance has not been documented. This was …

Bus Fleet Type And Age Replacement Optimization: A Case Study Utilizing King County Metro Fleet Data, Wei Feng, Miguel A. Figliozzi

Civil and Environmental Engineering Faculty Publications and Presentations

Bus fleet data have consistently shown that vehicle operating and maintenance costs increase as vehicles age. A fleet manager has to deal with the tradeoff between the lower operating and maintenance costs of newer fleets and their higher initial capital costs as well as the tradeoff between conventional and fuel efficient bus technologies. This study formulates and implements a fleet replacement optimization framework that is applied to a case study that compares two bus types: a conventional diesel and a hybrid bus. Employing real-world bus fleet data from King County Metro (Washington State, USA) multiple scenarios are examined to account …

Exploratory Methods For Truck Re-Identification In A Statewide Network Based On Axle Weight And Axle Spacing Data To Enhance Freight Metrics: Phase Ii, Mecit Cetin, Christopher M. Monsere

Civil and Environmental Engineering Faculty Publications and Presentations

Vehicle re-identification methods can be used to anonymously match vehicles crossing two different locations based on vehicle attribute data. This research builds upon a previous study and investigates different methods for solving the re-identification problem and explores some of the factors that impact the accuracy of the results. To support this work, archived data from weigh-in-motion (WIM) stations in Oregon are used for developing, calibrating, and testing vehicle re-identification algorithms. In addition to the Bayesian approach developed by the researchers in the previous study, a neural network model is developed for solving the re-identification problem. The results from the testing …

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 …

Examining The Effectiveness And Robustness Of Sequential Data Assimilation Methods For Quantification Of Uncertainty In Hydrologic Forecasting, Caleb Matthew Dechant, Hamid Moradkhani

Civil and Environmental Engineering Faculty Publications and Presentations

In hydrologic modeling, state-parameter estimation using data assimilation techniques is increasing in popularity. Several studies, using both the ensemble Kalman filter (EnKF) and the particle filter (PF) to estimate both model states and parameters have been published in recent years. Though there is increasing interest and a growing literature in this area, relatively little research has been presented to examine the effectiveness and robustness of these methods to estimate uncertainty. This study suggests that state-parameter estimation studies need to provide a more rigorous testing of these techniques than has previously been presented. With this in mind, this paper presents a …

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 …

Real-Time Change And Damage Detection Of Landslides And Other Earth Movements Threatening Public Infrastructure, Michael J. Olsen, Shawn Butcher, Evon P. Silvia

TREC Final Reports

Geologic hazards such as coastal erosion, landslides, seismic loading, etc. constantly threaten public highway construction and maintenance. Repeat surveys using terrestrial laser scanning (TLS, ground-based LiDAR) enable rapid 3D data acquisition to map, see, analyze, and understand the processes generating such problems. Previously, change detection and analysis between scan surveys was conducted during post-processing upon return to the office, instead of while collecting data in the field. Change detection in the field improves the effectiveness and efficiency of the field investigation. We have developed a new algorithm that quickly geo-references scans upon field acquisition and simultaneously performs change detection by …

Toward Reduction Of Model Uncertainty: Integration Of Bayesian Model Averaging And Data Assimilation, Mark A. Parrish, Hamid Moradkhani, Caleb Matthew Dechant

Civil and Environmental Engineering Faculty Publications and Presentations

Multimodeling in hydrologic forecasting has proved to improve upon the systematic bias and general limitations of a single model. This is typically done by establishing a new model as a linear combination or a weighted average of several models with weights on the basis of individual model performance in previous time steps. The most commonly used multimodeling method, Bayesian model averaging (BMA), assumes a fixed probability distribution around individual models' forecast in establishing the prior and uses a calibration period to determine static weights for each individual model. More recent work has focused on a sequential Bayesian model selection technique …

Development Of The Oregon Traffic Safety Data Archive: Phases 1 And 2, Christopher M. Monsere, Myenwoo Lim, Chengxin Dai, Xiaowei Wu

Civil and Environmental Engineering Faculty Publications and Presentations

This report describes the preliminary work to develop the Oregon Traffic Safety Data Archive (OrTSDA). The mission of OrTSDA is to "build the knowledge base of traffic safety data in Oregon". The archive hopes to become a valuable traffic safety data resource with researchers, practitioners, and community supporters. As envisioned, the archive will provide current and historical versions of related data, encompass complete documentation, and contain an online interface to the variety of traffic safety related data. Working with partner state agencies, the archive contains reported motor vehicle crashes statewide, population data, estimates of vehicle miles traveled, traffic crime, and …

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

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.

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 …

Strength And Fatigue Of Three Glass Fiber Reinforced Composite Bridge Decks With Mechanical Deck To Stringer Connections, Andrew Gleason, Peter Dusicka

Civil and Environmental Engineering Faculty Publications and Presentations

Replacement of the steel grating deck on the lift span of the Morrison Bridge in Portland, OR, will utilize glass fiber reinforced polymer (FRP) panels to address ongoing maintenance issues of the deteriorated existing deck, improve driver safety and introduce bridge water runoff treatment. This report outlines the testing methods and results of an experimental program aimed primarily at evaluating a new open cell deck. While most FRP panels are connected via shear studs that are grouted within isolated pockets, the panels in this case were bolted directly to the steel stringers. Two different FRP deck options were evaluated for …

Application Of Reference Models In Technology Management, Farshad Madani

Engineering and Technology Management Student Projects

Reference models, sometimes called with other different words, prepare a general model from a specific view of the related environment. Reference models are considered as a basic foundation to create: 1) a common language among specialists 2) a reference for the entities such as processes 3) relationships among entities 4) tools and decision making procedures for the real world.

In this report, it's tried the definitions of reference model in the selected papers have been reviewed. It's noticeable that in many papers the term of framework is used instead of reference model. Also, applications of reference models are reviewed and …

Plasma Levels Of Polychlorinated Biphenyls, Non-Hodgkin Lymphoma, And Causation, Michael D. Freeman, Sean S. Kohles

Mechanical and Materials Engineering Faculty Publications and Presentations

Polychlorinated biphenyls (PCBs) are synthetic chlorinated hydrocarbons that have extensively polluted the environment and bioaccumulated in the food chain. PCBs have been deemed to be probable carcinogens by the Environmental Protection Agency, and exposure to high levels of PCBs has been consistently linked to increased risk of non-Hodgkin lymphoma (NHL). In the present article we present a forensic epidemiologic evaluation of the causal relationship between NHL and elevated PCB levels via application of the Bradford-Hill criteria. Included in the evaluation is a meta-analysis of the results of previously published case-control studies in order to assess the strength of association between …

An Introduction To Technology Forecasting With A Tfdea Excel Add-In, Dong-Joon Lim, Timothy R. Anderson

Engineering and Technology Management Faculty Publications and Presentations

This paper describes an Excel add-in program that can run TFDEA (Technology Forecasting using Data Envelopment Anlaysis) within the spreadsheet. It utilizes freely available statistical software R and its packages developed by Statconn. This add-in allows access to both user-friendly tools for data manipulation in spreadsheet available and the power and precision of the results via R.

R&D Target-Setting Difficulties Addressed Through Emergent Method: Technology Forecasting Using Data Envelopment Analysis, Ann-Marie Lamb, Timothy R. Anderson, Tugrul Unsal Daim

Engineering and Technology Management Faculty Publications and Presentations

The aim of this study is to provide a foundation for researchers and managers to further discuss and resolve difficulties associated with R&D target-setting. While multiple studies mention the difficulty of R&D target-setting, few studies exist which compile reasons for these difficulties; nor do they address this issue in any detail. This paper provides what appears to be one of the first studies outlining reasons for R&D target-setting difficulties through a literature review; then also provides an initial set of analyses and results after applying an emerging quantitative method, Technology Forecasting Using Data Envelopment Analysis (TFDEA) addressing these difficulties, step-by-step …

Fuzzy Cognitive Maps To Implement Corporate Social Responsibility In Product Planning: A Novel Approach, Richard Sperry, Antonie J. Jetter

Engineering and Technology Management Faculty Publications and Presentations

Product development can support proactive CSR strategies by changing product features, materials, and processes in order to reduce or even eliminate negative environmental and social impacts. However, the CSR literature provides little practical guidance for new product development, but promotes general principles for responding to environmental and social issues. One of these guiding principles is the concept of stakeholder engagement, but to date, few practical approaches for integrating stakeholder views and needs into product development exist. To address this gap, the paper discusses the use of Fuzzy Cognitive Map Modeling. The method, which has been applied in participatory stakeholder studies …

Ultrasonic Wave Propagation Assessment Of Native Cartilage Explants And Hydrogel Scaffolds For Tissue Engineering, Sean S. Kohles, Shelley S. Mason, Anya P. Adams, Robert J. Berg, Jessica Blank, Fay Gibson, Johnathan Righetti, Lesha S. Washington, Asit K. Saha

Mechanical and Materials Engineering Faculty Publications and Presentations

Non-destructive techniques characterising the mechanical properties of cells, tissues, and biomaterials provide baseline metrics for tissue engineering design. Ultrasonic wave propagation and attenuation has previously demonstrated the dynamics of extracellular matrix synthesis in chondrocyte-seeded hydrogel constructs. In this paper, we describe an ultrasonic method to analyse two of the construct elements used to engineer articular cartilage in real-time, native cartilage explants and an agarose biomaterial. Results indicated a similarity in wave propagation velocity ranges for both longitudinal (1500-1745 m/s) and transverse (350-950 m/s) waveforms. Future work will apply an acoustoelastic analysis to distinguish between the fluid and solid properties including …

Tsunami Hydrodynamics In The Columbia River, Harry Yeh, Elena Tolkova, David A. Jay, Stefan A. Talke, Hermann Fritz

Civil and Environmental Engineering Faculty Publications and Presentations

On 11 March 2011, the Tohoku Tsunami overtopped a weir and penetrated 49 km up the Kitakami River, the fourth largest river in Japan. Similarly, the 2010 Chile tsunami propagated at least 15 km up the Maule River. In the Pacific Northwest of the United States, large tsunamis have occurred along the Cascadia subduction zone, most recently the 'orphan tsunami' of 1700 (Atwater et al.). The expected future occurrence of a Cascadia tsunami and its penetration into the Lower Columbia River became the subject of “the Workshop on Tsunami Hydrodynamics in a Large River” held in Corvallis, Oregon, 2011. We …

Identification Of The Biogenic Compounds Responsible For Size-Dependent Nanoparticle Growth, Paul M. Winkler, John Ortega, Thomas Karl, Luca Cappellin, Hans R. Friedli, Kelley Barsanti, Peter H. Mcmurry, James N. Smith

Civil and Environmental Engineering Faculty Publications and Presentations

The probability that freshly nucleated nanoparticles can survive to become cloud condensation nuclei is highly sensitive to particle growth rates. Much of the growth of newly formed ambient nanoparticles can be attributed to oxidized organic vapors originating from biogenic precursor gases. In this study we investigated the chemical composition of size-selected biogenic nanoparticles in the size range from 10 to 40 nm. Particles were formed in a flow tube reactor by ozonolysis ofα-pinene and analyzed with a Thermal Desorption Chemical Ionization Mass Spectrometer. While we found similar composition in 10 and 20 nm particles, the relative amounts of …

Climate Change Impact Assessment For Surface Transportation In The Pacific Northwest And Alaska, John Macarthur, Philip Mote, Miguel A. Figliozzi, Jason Ideker, Ming Lee

Civil and Environmental Engineering Faculty Publications and Presentations

The states in the Pacific Northwest and Alaska region share interconnected transportation networks for people, goods, and services that support the regional economy, mobility, and human safety. Regional weather has and will continue to affect the physical condition and serviceability of these networks, yet the nature of climate changes and their potential impacts on the regional transportation system and its use are very poorly understood. The world’s leading climate scientists, such as the Intergovernmental Panel for Climate Change, have reached consensus that global climate changes are being observed and will continue into the future, particularly increasing temperatures. Given this fact, …

Multiuser Perspectives On Separated, On-Street Bicycle Infrastructure, Christopher Monsere, Nathan Mcneil, Jennifer Dill

Civil and Environmental Engineering Faculty Publications and Presentations

In the early fall of 2009, the Bureau of Transportation in Portland, Oregon, installed a cycle track and a pair of buffered bike lanes in downtown Portland. A major objective was to test facilities that were thought to bring higher levels of comfort to bicycle riders through increased separation from motor vehicle traffic. After one year of use, an evaluation was conducted to determine how the facilities affected the experience of the various users. Intercept surveys of cyclists (n 5 248), motorists (n 5 262), pedestrians (n 5 198), and adjacent businesses (n 5 59) showed improved perceptions of safety …