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Guidance Index For Shallow Landslide Hazard Analysis, Cheila Cullen 2016 The Graduate Center, City University of New York

Guidance Index For Shallow Landslide Hazard Analysis, Cheila Cullen

All Graduate Works by Year: Dissertations, Theses, and Capstone Projects

Rainfall-induced landslides are one of the most frequent hazards on slanted terrains. They lead to considerable economic losses and fatalities worldwide. Intense storms with high-intensity and long-duration rainfall have high potential to trigger rapidly moving soil masses due to changes in pore water pressure and seepage forces. Nevertheless, regardless of the intensity-duration of the rainfall, shallow landslides are influenced by antecedent soil moisture conditions. To the present day, no system exists that dynamically interrelates these two factors.

This work establishes a relationship between antecedent soil moisture and rainfall expressed in the form of a Shallow Landslide Index (SLI) at 1km ...


Numerical Studies For Improving Fracture Toughness Resistance Curve Testing Using Single-Edge (Notched) Tension Specimens, Yifan Huang 2016 The University of Western Ontario

Numerical Studies For Improving Fracture Toughness Resistance Curve Testing Using Single-Edge (Notched) Tension Specimens, Yifan Huang

Electronic Thesis and Dissertation Repository

The fracture toughness resistance curve, i.e. the J-integral resistance curve (J-R curve) or the crack tip opening displacement resistance (CTOD-R) curves, is widely used in the integrity assessment and strain-based design of energy pipelines with respect to planar defects (i.e. cracks). This thesis deals with issues related to the experimental determination of the J(CTOD)-R curves using the newly-developed single-edge (notched) tension (SE(T)) specimens. In the first study, the plastic geometry factor, i.e. the ηpl factor, used to evaluate J in a J-R curve test based on the SE(T ...


Exploring Factors Contributing To Injury Severity At Freeway Merging And Diverging Locations In Ohio, Worku Y. Mergia, Deogratias Eustace, Deo Chimba, Maher Butros Qumsiyeh 2016 Geotest Engineering, Houston, Texas

Exploring Factors Contributing To Injury Severity At Freeway Merging And Diverging Locations In Ohio, Worku Y. Mergia, Deogratias Eustace, Deo Chimba, Maher Butros Qumsiyeh

Maher Qumsiyeh

Identifying factors that affect crash injury severity and understanding how these factors affect injury severity is critical in planning and implementing highway safety improvement programs. Factors such as driver-related, traffic-related, environment-related and geometric design-related were considered when developing statistical models to predict the effects of these factors on the severity of injuries sustained from motor vehicle crashes at merging and diverging locations. Police-reported crash data at selected freeway merging and diverging areas in the state of Ohio were used for the development of the models. A generalized ordinal logit model also known as partial proportional odds model was applied to ...


Analyzing The Effects Of Led Traffic Signals On Urban Intersection Safety, Deogratias Eustace, Valerie E. Griffin, Peter W. Hovey 2016 University of Dayton

Analyzing The Effects Of Led Traffic Signals On Urban Intersection Safety, Deogratias Eustace, Valerie E. Griffin, Peter W. Hovey

Deogratias Eustace

In 2002, there were 1,299,000 crashes at signalized intersections in the United States. These crashes account for approximately 21 percent of total crashes and about 24 percent of all fatal and injury collisions. The social and financial impact of this number of collisions is substantial. The Federal Highway Administration (FHWA) and other agencies have recognized the detrimental effects of intersection crashes on our society and continue to fund research that will lead to a decrease in crash frequency. Numerous countermeasures have been tested for their potential to reduce crashes. Infrastructure improvements such as the construction of left-turn lanes ...


An Exploratory Survey Of Drivers’ Knowledge Of Right Of Way At Freeway On-Ramp Merging Areas, Deogratias Eustace, Stephen Owusu-Ansah, Vamsi Krishna Indupuru 2016 University of Dayton

An Exploratory Survey Of Drivers’ Knowledge Of Right Of Way At Freeway On-Ramp Merging Areas, Deogratias Eustace, Stephen Owusu-Ansah, Vamsi Krishna Indupuru

Deogratias Eustace

Motor vehicle crashes are one of the leading causes of death in the United States. The most recent data available show that in 2006 there were almost 6 million police-reported motor vehicle crashes in the United States where a total of 42,642 people were killed and an additional 2.6 million were injured. The majority of these motor vehicle crashes occurred at intersections or within the intersection influence areas. Traffic conflicts occur at intersections due to traffic streams moving in different directions interfering with each other, and as a result they become areas with high potential for traffic crashes ...


Public Transport Accessibility Levels For Ahmedabad, India, Jay S. Shah, Bhargav Adhvaryu 2016 Transport Planning Consultant, India

Public Transport Accessibility Levels For Ahmedabad, India, Jay S. Shah, Bhargav Adhvaryu

Journal of Public Transportation

Public transport plays an important role in a city’s economy and its social equity. It is also instrumental in reducing automobile dependence and traffic congestion. Several factors must come together to achieve well-functioning public transport systems. One major factor is the level of accessibility offered by the public transport system. To better understand and consequentially enhance accessibility, we must be able to measure it and map it, which is the key aim of this paper.

The methodology in this study, which was originally developed by the London Borough of Hammersmith and Fulham and later adopted by Transport for London ...


Modeling Bus Dwell Time And Time Lost Serving Stop In China, Chao Wang, Zhirui Ye, Yuan Wang, Yueru Xu, Wei Wang 2016 Southeast University, China

Modeling Bus Dwell Time And Time Lost Serving Stop In China, Chao Wang, Zhirui Ye, Yuan Wang, Yueru Xu, Wei Wang

Journal of Public Transportation

The primary objective of this study was to develop a quantitative approach to estimate bus dwell time and time lost serving stop, which included acceleration and deceleration time, dead time, and time for serving boarding and alighting passengers. A polynomial model incorporating kinematics of a particle was derived for estimating bus acceleration and deceleration time. In addition, descriptive statistics methods were used to analyze dead time. A case study was conducted to show the applicability of the proposed model with data collected from the seven most common types of bus stops in China. R-square and Mean Absolute Percentage Error (MAPE ...


Public Transport Crowding Valuation: Evidence From College Students In Guangzhou, Jianrong Liu, Huiying Wen 2016 South China University of Technology

Public Transport Crowding Valuation: Evidence From College Students In Guangzhou, Jianrong Liu, Huiying Wen

Journal of Public Transportation

Overcrowding has grown to be an increasingly important issue for public transit in Guangzhou, China. To capture traveler benefits of reduced crowding from improved public transport, it is necessary to identify the relevant importance of crowding to travelers. This paper analyzes the disutility of crowding in metro car and bus transit with discrete choice models. Based on the stated preference survey data from college students in Guangzhou, the results show that there is non-negligible impact of crowding on passenger travel. The relationship between the disutility of crowding and standee density is not linear; that is, the disutility increases at a ...


Cross-Elasticities In Frequencies And Ridership For Urban Local Routes, Joseph Totten, David Levinson 2016 University of Minnesota - Twin Cities

Cross-Elasticities In Frequencies And Ridership For Urban Local Routes, Joseph Totten, David Levinson

Journal of Public Transportation

Observational data from the Minneapolis-Saint Paul region’s Metro Transit were analyzed to determine the effects of service levels on ridership levels at different intervals. The research compares changes in service levels and ridership in several service intervals and includes elasticities and cross elasticities, or the influence that these service levels have on different service intervals’ ridership. These cross-elasticities were found to have little effect during the week; however, weekend ridership was found to be influenced by rush-hour and overnight frequencies.


Evaluation Of Horizontal Equity Under A Distance-Based Transit Fare Structure, Milad Bandegani, Meisam Akbarzadeh 2016 Isfahan University of Technology

Evaluation Of Horizontal Equity Under A Distance-Based Transit Fare Structure, Milad Bandegani, Meisam Akbarzadeh

Journal of Public Transportation

Horizontal equity requires equal distribution of investment/benefit/costs among equal members of society. In other words, a transit passenger should pay as much as he/she uses. This study evaluated the measure of fulfillment of this rule in a case study, developed a distance-based fare structure, and shows that justice is better served by switching to the proposed structure. Fare elasticity of demand and probability distribution of transit passenger trip lengths were investigated through a field survey. Although mainly used in the measurement of inequality in income or wealth, the Gini index and the recovery ratio (revenue to cost ...


Modeling Transit Users Stop Choice Behavior: Do Travelers Strategize?, Mohammad Nurul Hassan, Taha Hossein Rashidi, S. Travis Waller, Neema Nassir, Mark Hickman 2016 University of New South Wales

Modeling Transit Users Stop Choice Behavior: Do Travelers Strategize?, Mohammad Nurul Hassan, Taha Hossein Rashidi, S. Travis Waller, Neema Nassir, Mark Hickman

Journal of Public Transportation

Transit choice research focuses predominantly on mode choice and route choice, whereas very few studies on stop choice are conducted. To fill this gap, this research aimed to study transit stop choice behavior with a focus on how people strategize when making their choices. It is hypothesized that travelers treat stops differently based on various schemes (strategies); minimizing travel time, access time, and the number of transfers are the schemes considered in this study, and the effectiveness of several discrete choice model specifications was examined. The study found that path attributes and stop attributes have significant impacts on stop selection ...


Effects Of Speed, Curves, And Driver Behavior On Passive Securement Systems On Large Transit Buses, Andrea Mather, Katharine Hunter-Zaworski 2016 Oregon State University

Effects Of Speed, Curves, And Driver Behavior On Passive Securement Systems On Large Transit Buses, Andrea Mather, Katharine Hunter-Zaworski

Journal of Public Transportation

Wheeled mobility devices that are not secured properly on large transit vehicles pose risks to all passengers. The purpose of this study was to increase the understanding of the effects of horizontal and vertical curves, speed, and driver behavior on the safety and security of people using wheeled mobility devices in rear-facing passive containment systems on large transit buses. Testing included the use of manual wheelchairs and lightweight scooters on an articulated low-floor transit bus. The project conclusions were derived from data produced by accelerometers placed on the bus as well as visual observations of wheeled mobility device movement. The ...


Portable Modular Conveyor, Purdue ECT Team 2016 Purdue University

Portable Modular Conveyor, Purdue Ect Team

ECT Fact Sheets

The Portable Modular Conveyor-Material Placer (PMC) is a quick, easy, dependable and cost effective way to place materials in the limits of the confined grade or work area. This specialized piece of equipment was developed to place concrete in front of a concrete slip form-paving machine. The typical method of placing concrete requires a self-propelled belt placer, which is very expensive to purchase and mobilize to the jobsite. The PMC creates a significant cost savings in labor and equipment with the PMC. It is a direct replacement for conventional material placing equipment, including all in grade belt placing machines. As ...


Tidal-Fluvial And Estuarine Processes In The Lower Columbia River: Ii. Water Level Models, Floodplain Wetland Inundation, And System Zones, David A. Jay, Amy B. Borde, Heida Diefenderfer 2016 Portland State University

Tidal-Fluvial And Estuarine Processes In The Lower Columbia River: Ii. Water Level Models, Floodplain Wetland Inundation, And System Zones, David A. Jay, Amy B. Borde, Heida Diefenderfer

Civil and Environmental Engineering Faculty Publications and Presentations

Spatially varying water-level regimes are a factor controlling estuarine and tidal-fluvial wetland vegetation patterns. As described in Part I, water levels in the Lower Columbia River and estuary (LCRE) are influenced by tides, river flow, hydropower operations, and coastal processes. In Part II, regression models based on tidal theory are used to quantify the role of these processes in determining water levels in the mainstem river and floodplain wetlands, and to provide 21-year inundation hindcasts. Analyses are conducted at 19 LCRE mainstem channel stations and 23 tidally exposed floodplain wetland stations. Sum exceedance values (SEVs) are used to compare wetland ...


Experimental Study On Local Bond Stress-Slip Relationship In Self-Compacting Concrete, Marian Sabau, Ioan Pop, Traian Onet 2016 Universidad de la Costa

Experimental Study On Local Bond Stress-Slip Relationship In Self-Compacting Concrete, Marian Sabau, Ioan Pop, Traian Onet

Marian Sabau

This paper summarizes the results of an experimental study on local bond stress-slip relationship of deformed reinforcing bars embedded in self-compacting concrete, considering the effect of concrete confinement by transverse reinforcement. In this study were cast 104 specimens by using self-compacting concrete and vibrated concrete. Pull-out tests were performed on deformed bars with short anchorage length (ld ≤ 5∅). The parameters analyzed were the concrete type, the confining reinforcement, the bar diameter and the anchorage length of bar. The results of this study showed that the ultimate bond strength was higher for self-compacting concrete compared to vibrated concrete, and the slip ...


Removal Of Target Ppcps From Secondary Effluent Using Aops And Novel Adsorbents, Venkateswara Reddy Kandlakuti 2016 The University of Western Ontario

Removal Of Target Ppcps From Secondary Effluent Using Aops And Novel Adsorbents, Venkateswara Reddy Kandlakuti

Electronic Thesis and Dissertation Repository

Atenolol (β-blocker), Clofibric Acid (Lipid regulators) and Diclofenac (Anti-inflammatory) are the drugs widely used and reported to have adverse effects on fish and other organisms. These drugs are found at trace levels in lakes, rivers and sewage treatment plants and conventional treatment plants are ineffective to eliminate these at those levels. A high resolution LC-MS/MS was used to quantify these drugs at low levels. Various advanced oxidation methods were used for the present research to eliminate these drugs from secondary effluent. Complete removal of PPCPs was achieved by synthesizing immobilized TiO2 on a stainless steel mesh and using a ...


Estimation Of Wind Hazard Over Canada And Reliability-Based Assignment Of Design Wind Load, Qian Tang 2016 The University of Western Ontario

Estimation Of Wind Hazard Over Canada And Reliability-Based Assignment Of Design Wind Load, Qian Tang

Electronic Thesis and Dissertation Repository

The current National Building Code of Canada (NBCC) recommends a wind load factor of 1.4 and the nominal wind velocity pressure corresponding to 50-year return period value of the annual maximum hourly-mean wind speed, VAH. This study is focused on mapping wind hazard for Canada and on calibrating the required design wind load to improve reliability consistency of the designed structures.

Extreme value analysis of VAH was carried out by considering surface wind observations from approximately 1300 stations. The results indicate that the spatial trends of the estimated mean of VAH are similar whether the data ...


Soil Aquifer Treatment For Wastewater Reclamation In A High Water Demand Society, Diego J. Velasquez 2016 The University of Western Ontario

Soil Aquifer Treatment For Wastewater Reclamation In A High Water Demand Society, Diego J. Velasquez

Electronic Thesis and Dissertation Repository

Water resources around the world are under increasing pressure from the rapidly growing demands of rising population and industrialization. Furthermore, changes in global weather patterns are expected to intensify its current and future stresses. In the present study, knowledge and perceptions towards wastewater reclamation for potable and non-potable uses were investigated by the used of an on-line survey distributed amongst the university community at Western university. Subsequent statistical analysis of the results was performed using IBM-SPSS software. Survey results show that member of the university community are more likely to accept reclaimed wastewater for applications that do not involve drinking ...


Beyond Global Warming Potential: A Comparative Application Of Climate Impact Metrics For The Life Cycle Assessment Of Coal And Natural Gas Based Electricity, DeVynne Farquharson, Paulina Jaramillo, Greg Schivley, Kelly Klima, Derrick R. Carlson, Constantine Samaras 2016 Carnegie Mellon University

Beyond Global Warming Potential: A Comparative Application Of Climate Impact Metrics For The Life Cycle Assessment Of Coal And Natural Gas Based Electricity, Devynne Farquharson, Paulina Jaramillo, Greg Schivley, Kelly Klima, Derrick R. Carlson, Constantine Samaras

Department of Engineering and Public Policy

In the ongoing debate about the climate benefits of fuel switching from coal to natural gas for power generation, the metrics used to model climate impacts may be important. In this article, we evaluate the life cycle greenhouse gas emissions of coal and natural gas used in new, advanced power plants using a broad set of available climate metrics in order to test for the robustness of results. Climate metrics included in the article are global warming potential, global temperature change potential, technology warming potential, and cumulative radiative forcing. We also used the Model for the Assessment of Greenhouse-gas Induced ...


Rubble Pile Characterization Model, William P. Schonberg, Jason Baird, Paul Nicholas Worsey, Abdeldjelil Belarbi, Roger A. LaBoube, Braden Lusk, R. Flanagan, H. Burleson, Robert S. Woodley, Warren Noll 2016 Missouri University of Science and Technology

Rubble Pile Characterization Model, William P. Schonberg, Jason Baird, Paul Nicholas Worsey, Abdeldjelil Belarbi, Roger A. Laboube, Braden Lusk, R. Flanagan, H. Burleson, Robert S. Woodley, Warren Noll

Paul Worsey

Rubble piles created following the collapse of a building in a combat situation can significantly impact mission accomplishment, particularly in the area of movement and maneuver. Rubble characteristics must be known, for example, in order to predict the ability of a vehicle to override the collateral damage from weapon effects in urban areas. Two types of models are developed: a first-order model and a first-principles-based model. In both models, we assume complete rubblization of the building and develop a rubble profile model using the size and composition of the collapsed structure to predict the rubble volume. In both cases, this ...


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