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Geospatial Analysis Of Rural Motor Vehicle Traffic Crashes In Oregon, Saad Nayef AlMutairi 2014 Portland State University

Geospatial Analysis Of Rural Motor Vehicle Traffic Crashes In Oregon, Saad Nayef Almutairi

Civil and Environmental Engineering Master's Project Reports

This research examines the spatial extent of crashes in and around city boundaries in the state of Oregon in the U.S.A. For this study, summary of fatalities data for the year 2006 obtained from NHTSA’s report (2009), crash data for the year 2012, and city boundaries were obtained from ODOT “Oregon Department of Transportation” FTP: www.odot.state.or.us. In order to differentiate between the urban and rural crashes, city boundaries were used to find the numbers of urban and rural crashes. Outside areas of this urban-rural boundary were divided into further boundaries of 2.5 ...


Failures Of Mainline Railway Sleepers And Suggested Remedies-Review Of Current Practice, Wahid Ferdous 2014 SelectedWorks

Failures Of Mainline Railway Sleepers And Suggested Remedies-Review Of Current Practice, Wahid Ferdous

Wahid Ferdous

Over the last two decades, the premature failures of traditional railway sleepers have significantly increased the track maintenance costs. The primary obstacle to minimising this problem is the lack of understanding of the mechanism of sleeper degradation. This paper discusses the different deterioration mechanisms for traditional timber, concrete and steel sleepers and the potential protective measures to minimise these problems. This paper exhaustively reviews the failure mechanisms of these three commonly used sleeper materials with suggested solutions. Fungal decay, end splitting and termite attacks has been identified as the principal causes of timber sleeper failures. On the other hand, concrete ...


Probabilistic Modeling And Bayesian Inference Of Metal-Loss Corrosion With Application In Reliability Analysis For Energy Pipelines, Hao Qin 2014 Western University

Probabilistic Modeling And Bayesian Inference Of Metal-Loss Corrosion With Application In Reliability Analysis For Energy Pipelines, Hao Qin

University of Western Ontario - Electronic Thesis and Dissertation Repository

The stochastic process-based models are developed to characterize the generation and growth of metal-loss corrosion defects on oil and gas steel pipelines. The generation of corrosion defects over time is characterized by the non-homogenous Poisson process, and the growth of depths of individual defects is modeled by the non-homogenous gamma process (NHGP). The defect generation and growth models are formulated in a hierarchical Bayesian framework, whereby the parameters of the models are evaluated from the in-line inspection (ILI) data through the Bayesian updating by accounting for the probability of detection (POD) and measurement errors associated with the ILI data. The ...


Evaluation Of Truck Signal Priority At N Columbia Blvd And Martin Luther King Jr. Blvd Intersection, Maisha Mahmud 2014 Portland State University

Evaluation Of Truck Signal Priority At N Columbia Blvd And Martin Luther King Jr. Blvd Intersection, Maisha Mahmud

Civil and Environmental Engineering Master's Project Reports

Given the importance of over growing freight transportation system worldwide, engineers and planners are faced with the challenge of improving freight service in urban area using low cost measure. Truck Signal Priority is one of the strategy that can be used to improve operational efficiency with enhance safety benefits (red light running) of freight service, without major capital investment. In light to this interest this study focus on evaluating the impacts of freight signal priority on a high truck density intersection like N Columbia Blvd and NE Martin Luther King Jr. Blvd. Using a simulation tool, VISSIM, these impacts were ...


Wind-Induced Pressures In Air Permeable, Double-Layer Roof Systems In Regions Of Separated Flow, Jeong Hee Oh 2014 Western University

Wind-Induced Pressures In Air Permeable, Double-Layer Roof Systems In Regions Of Separated Flow, Jeong Hee Oh

University of Western Ontario - Electronic Thesis and Dissertation Repository

This thesis is concerned with the wind-induced pressure distribution acting on air permeable, double-layer roof systems placed on low-rise buildings. Because of the pressure transmission into the cavity between layers, the pressure difference in the double-layer systems differs significantly from that in a single layer. The interior pressures (in the cavity between layers) are highly correlated with external pressures at the openings on the external surface of the outer layer and thereby, the net wind load for the design of the outer layer is considerably reduced by the pressure equalization between the external and internal surfaces of the outer layer ...


Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng 2014 Western University

Solid-Phase Extraction As Sample Preparation For Bioassay-Based Micropollutant Quantification, Chen Feng

University of Western Ontario - Electronic Thesis and Dissertation Repository

Solid phase extraction (SPE) using chemically bonded silica particles or small particles of an organic polymer resin, is being studied extensively for extraction of polar or non-polar compounds from various water matrices. This study focused on the evaluation of the performance of three commercial cartridges belonging to three different groups: reversed-phase, mixed-mode anion exchanger and mixed-mode cation exchanger. In the first stage of research, the performance of three cartridges was compared by extracting four antibiotics with different physic-chemical properties from water samples. The results obtained from column sorption experiments were plotted into breakthrough curves and batch equilibrium experiments results were ...


Characterization Of The Green Roof Growth Media, Ginevra Alessandra Perelli 2014 Western University

Characterization Of The Green Roof Growth Media, Ginevra Alessandra Perelli

University of Western Ontario - Electronic Thesis and Dissertation Repository

Green roofs are becoming a popular solution to manage the stormwater, to reduce the energy consumption in highly urbanized environment and provide many additional benefits. One of the key components that characterize the green roof system is the growth medium; the medium supports the plants, providing water and nutrient storage, and contributes to the roof insulation.

The object of this thesis is to investigate the hydraulic and the thermal properties of the green roof growth medium and to study the relationship among these properties through extensive laboratory analyses. In addition, the laboratory results are compared with direct measurements in the ...


Instrumentation To Monitor Bridge Foundation On The Crosstown Project, Brian Welch 2014 Minnesota State University, Mankato

Instrumentation To Monitor Bridge Foundation On The Crosstown Project, Brian Welch

Journal of Undergraduate Research at Minnesota State University, Mankato

The Crosstown Bridge Monitoring Project is located at the intersection of Highway 62 and Interstate I35W a few miles south and west of downtown Minneapolis. The bridge being evaluated is at a railroad overpass located midway along the Crosstown expansion. This research project involved placing instrumentation on the bridge foundation in order to measure the change in the foundation loading during the course of the construction project. For several years there have been questions pertaining to the forces in the pile foundations that support highway embankments. This project placed strain gages on the pile foundations in order to monitor these ...


Assessment Of Policies For Innovative Financing In Infrastructure Systems, Ali Mostafavi, Dulcy Abraham, Charlene Sullivan 2014 Florida International University

Assessment Of Policies For Innovative Financing In Infrastructure Systems, Ali Mostafavi, Dulcy Abraham, Charlene Sullivan

Infrastructure System-of-Systems (I-SoS ) Research Group

Infrastructure systems are drivers of the economy in the nation. A dollar spent on infrastructure development yields roughly double the initial spending in ultimate economic output in the short term; and over a twenty-year period, and generalized ‘public investment’ produces an aggregated $3.21 of economic activity per $1.00 spent [1]. Thus, formulation of policies pertaining to infrastructure investment and development is of significance affecting the social and economic wellbeing of the nation. The aim of this policy brief is to evaluate innovative financing in infrastructure systems from two different perspectives: (1) through consideration of the current condition of ...


Turbulent Circular Culvert Flow: Implications To Fish Passage Design, Amin Mohebbi 2014 University of Nebraska - Lincoln

Turbulent Circular Culvert Flow: Implications To Fish Passage Design, Amin Mohebbi

Civil Engineering Theses, Dissertations, and Student Research

Culverts are popular conveyance structures in America and Canada to be used as a fish passage or in sewage collection and disposal systems. Fish passage design criteria is based on biological capabilities of fish whereas it should satisfy hydraulic and hydrological constraints as well. Failing to provide enough low velocity regions for aquatic organisms may result in their mass extinctions. Currently, proper road crossing design depends on either model studies or numerical simulations via Computational Fluid Dynamic (CFD) packages, both of which are expensive and time consuming. Further, although the design procedures released by FHWA recently ensures safe fish migration ...


A Cost Benefit Analysis Of Improving Energy Efficiency Of A Fitness Facilty, Inuri A. Illeperuma 2014 Colby College

A Cost Benefit Analysis Of Improving Energy Efficiency Of A Fitness Facilty, Inuri A. Illeperuma

Journal of Environmental and Resource Economics at Colby

Abstract: Nearly 40% of the total U.S. energy consumption in 2012 was consumed in residential and commercial buildings, as recorded by U.S. Energy Information Administration. With the urgent need to reduce overall energy consumption in the U.S., many efforts are made to improve the energy efficiency of buildings. However, energy managers identify budget constraints as one of the main obstacles in improving the energy efficiency of buildings. Hence this study focuses on a cost benefit analysis of improving the energy efficiency, with a special focus on fitness facilities in college environments. As a case study, the author ...


Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta 2014 Western University

Enhancement Of Biohydrogen Production From Co-Fermentation Of Glucose, Starch, And Cellulose, Medhavi Gupta

University of Western Ontario - Electronic Thesis and Dissertation Repository

The aim of this study was to assess the synergistic effects of co-fermentation of glucose, starch, and cellulose using anaerobic digester sludge (ADS) on the biohydrogen (H2) production and the associated microbial communities. At initial pH of 5.5 and mesophilic temperature of 37 ºC, the H2 yields were greater by an average of 27 ± 4% in all the different co-substrate conditions compared to the mono-substrate conditions, which affirmed that co-fermentation of different substrates improved the hydrogen potential. The sensitivity of mesophilic ADS to a temperature shock was also investigated. Unacclimatized mesophilic ADS responded well to a temperature ...


Analysis Of Horizontal Directional Drilling Construction Risks Using The Probability-Impact Model: A Contractor’S Perspective., Lameck Onsarigo, Simon Asinor Adamtey, Alan Atalah 2014 Bowling Green State University

Analysis Of Horizontal Directional Drilling Construction Risks Using The Probability-Impact Model: A Contractor’S Perspective., Lameck Onsarigo, Simon Asinor Adamtey, Alan Atalah

Alan Atalah

All projects are subject to risks that have both a direct and indirect effect on the project cost and time. The risks vary from project to project because of the unique nature of each project. It is important for the project management team to include risk management as an integral part of their project planning and execution. Risk management strategies should be incorporated in every phase of an HDD project to ensure that the project meets the required quality and safety standards, and that the project delivery is within cost and schedule. This paper takes a look at Horizontal Directional ...


An Introduction To Environmental Value Engineering (Eve) And The Eve Assessment Of Horizontal Directional Drilling (Hdd) Versus Open-Cut Construction, Lameck Mairura Onsarigo, Alan Atalah, Wilfred Harold Roudebush 2014 Bowling Green State University

An Introduction To Environmental Value Engineering (Eve) And The Eve Assessment Of Horizontal Directional Drilling (Hdd) Versus Open-Cut Construction, Lameck Mairura Onsarigo, Alan Atalah, Wilfred Harold Roudebush

Alan Atalah

The wastewater collection and water distribution systems in the United States are deteriorating at an alarming rate. The ever-growing need for rehabilitation and replacement of these systems led to the birth of a research program by the United States Environmental Protection Agency, Innovation and Research for Water Infrastructure for the 21st Century, which focused on addressing the water infrastructure needs. There is a need to responsively manage energy and environmental resources, which calls for the use of evaluation tools to compare competing alternatives with a view of adopting the most environmental friendly alternative. This paper gives an overview of the ...


Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer 2014 University of Nebraska - Lincoln

Infiltration And Runoff Parameters For Tilled And No-Till Row Crops, Andrew J. Volkmer

Biological Systems Engineering--Dissertations, Theses, and Student Research

Infiltration and runoff are hydrologic processes that effect the amount of water available to plants, for groundwater recharge, and for stream flow. No-till planting (NT) is a management practice used to reduce soil erosion, increase water infiltration, and reduce soil water evaporation, and can have great impact on infiltration and runoff. An investigation was conducted to determine the impact of NT on infiltration and runoff when compared to tilled conditions.

Runoff and precipitation data was gathered from sites at Fillmore County, NE, Phelps County, NE, the USDA-ARS North Appalachian Experimental Watersheds (NAEW) near Coshocton, OH, and the Lennoxville Research Station ...


Evaluating The Impact Of Bridge Deck Removal Method On The Performance Of Precast/Prestressed Concrete I-Girders, Shaddi Assad 2014 University of Nebraska - Lincoln

Evaluating The Impact Of Bridge Deck Removal Method On The Performance Of Precast/Prestressed Concrete I-Girders, Shaddi Assad

Construction Systems -- Dissertations & Theses

Wide flange precast/prestressed concrete I-girders have been widely used by several State Departments of Transportation (DOTs) in the last two decades. These girders have many advantages over standard AASHTO I-girders. Their wide and thick bottom flange accommodates a large number of prestressing strands and their wide and thin top flange provides a shorter deck span, reduced girder weight, greater stability in construction, and adequate platform for workers. Despite these advantages, the wide and thin top flange might be disadvantageous when it comes to deck removal, as it is more susceptible to damage. Therefore there is a need to investigate ...


A Comparative Assessment Of Crowded Source Travel Time Estimates: A Case Study Of Bluetooth Vs Inrix On A Suburban Arterial, Fahad Alhajri 2014 Portland State University

A Comparative Assessment Of Crowded Source Travel Time Estimates: A Case Study Of Bluetooth Vs Inrix On A Suburban Arterial, Fahad Alhajri

Civil and Environmental Engineering Master's Project Reports

Travel time is one of the most widely used measures of traffic performance monitoring for the transportation systems. It is a simple concept that refers to the time required to traverse between two points of interest. Travel time is communicated and used by a wide variety of audience such as commuters, media reporters, and transportation engineers and planners. Recent developments within the wireless communication area made it possible to collect travel time data at a relatively low cost. These emerging technologies include mobile phone based technologies, in-vehicle navigation technologies and automatic vehicle identification technologies. Although these technologies offer a great ...


Laser-Based Structural Sensing And Surface Damage Detection, Burcu Guldur 2014 Northeastern University

Laser-Based Structural Sensing And Surface Damage Detection, Burcu Guldur

Civil Engineering Dissertations

Damage due to age or accumulated damage from hazards on existing structures poses a worldwide problem. In order to evaluate the current status of aging, deteriorating and damaged structures, it is vital to accurately assess the present conditions. It is possible to capture the in situ condition of structures by using laser scanners that create dense three-dimensional point clouds. This research investigates the use of high resolution three-dimensional terrestrial laser scanners with image capturing abilities as tools to capture geometric range data of complex scenes for structural engineering applications. Laser scanning technology is continuously improving, with commonly available scanners now ...


Hollow Massive Timber Panels: A High-Performance, Long-Span Alternative To Cross Laminated Timber, William Graham Montgomery 2014 Clemson University

Hollow Massive Timber Panels: A High-Performance, Long-Span Alternative To Cross Laminated Timber, William Graham Montgomery

All Dissertations

Since the development of Cross Laminated Timber (CLT), there has been a surge in interest in massive timber buildings. Furthermore, recent conceptual and feasibility designs of massive timber towers of 30 or more stories indicate that performance of mass timber structural elements can compete with other building materials in the commercial industry (MGB Architecture and Design et al.). However, in order for massive timber to penetrate the commercial market even further, a solution is needed for long-span massive timber floor systems. Unfortunately, CLT falls short in this area and is unable to span long distances. The hollow massive timber (HMT ...


Treatment Of Nitrogen Oxides By Chlorella Vulgaris Algae In Photobioreactors, Steven Shihady 2014 California Polytechnic State University

Treatment Of Nitrogen Oxides By Chlorella Vulgaris Algae In Photobioreactors, Steven Shihady

Master's Theses and Project Reports

The effectiveness of algae to treat NO2and NO in simulated flue gas was tested using Chlorella vulgaris in photobioreactors (PBRs) using NOxconcentrations between 30 ppm to 780 ppm. NOxdissolved and reacted in water to form NO3-and NO2-in the PBR growth medium, providing a nitrogen source that the algae readily assimilated for cell synthesis. Three 20-L photobioreactors were inoculated with a pure culture of C. vulgaris prepared in Bristol growth medium and algae were grown in the PBRs at 25°C and pH of 7.0 in a modified Bristol medium ...


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