Engineering Commons^™

Hardware-In-The-Loop Simulation To Evaluate The Performance And Constraints Of The Red-Light Violation Warning Application On Arterial Roads, Mahmoud Arafat

FIU Electronic Theses and Dissertations

Understanding the safety and mobility impacts of Connected Vehicle (CV) applications is critical for ensuring effective implementations of these applications. This dissertation provides an assessment of the safety and mobility impacts of the Red-Light Violation Warning (RLVW), a CV-based application at signalized intersections, under pre-timed signal control and semi-actuated signal control utilizing Emulator-in-the-loop (EILS), Software-in-the-loop (SILS), and Hardware-in-the-loop simulation (HILS) environments. Modern actuated traffic signal controllers contain several features with which controllers can provide varying green intervals for actuated phases, skip phases, and terminate phases depending on the traffic demand fluctuation from cycle to cycle. With actuated traffic signal operations, …

Modeling Strategies For Structures Using Ductile Concrete Materials In Seismic Applications, Hasan Tariq

Dissertations

No abstract provided.

A Calibration Chamber For Thermo-Hydro-Mechanical Studies Of Soil Behavior Via Resonant Column Testing, Daniel R. C. Green

Civil Engineering Theses

Abstract A Calibration Chamber for Thermo-hydro-mechanical Studies of Soil Behavior via Resonant Column Testing Daniel R. C. Green The University of Texas at Arlington, 2018 Supervising Professor: Dr. Laureano Hoyos A considerable portion of the emerging geothermal infrastructure in the country is located in earthquake prone areas while being supported and/or surrounded by soil deposits located well above the groundwater table. Geotechnical earthquake research in the country, however, continues to be mostly focused on soil response under saturated conditions, especially soil liquefaction phenomena, while most of the work on dynamic response of compacted soils has not taken suction or thermal …

Calibrating And Evaluating Dynamic Rule-Based Transit-Signal-Priority Control Systems In Urban Traffic Networks, Md Didarul Alam

Civil and Environmental Engineering Dissertations

Setting the traffic controller parameters to perform effectively in real-time is a challenging task, and it entails setting several parameters to best suit some predicted traffic conditions. This study presents the framework and method that entail the application of the Response Surface Methodology (RSM) to calibrate the parameters of any control system incorporating advanced traffic management strategies (e.g., the complex integrated traffic control system developed by Ahmed and Hawas). The integrated system is a rule-based heuristic controller that reacts to specific triggering conditions, such as identification of priority transit vehicle, downstream signal congestion, and incidents by penalizing the predefined objective …

Calibration Of Microscopic Traffic Flow Models Enabling Simultaneous Selection Of Specific Links And Parameters, Kul Prasad Shrestha

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study proposes a methodology for the calibration of microscopic traffic flow simulation models by enabling simultaneous selection of traffic links and associated parameters. That is, any number and combination of links and model parameters can be selected for calibration. Most calibration approaches consider the entire network without enabling a specific selection of location and associated parameters. In practice, only a subset of links and parameters are used for calibration based on a number of factors such as expert local knowledge of the system. In this study, the calibration problem for the simultaneous selection of links and parameters was formulated …

Calibration Of Mepdg Performance Models For Flexible Pavement Distresses To Local Conditions Of Ontario, Nelson Fernando Cunha Coelho

Civil Engineering Theses

The implementation of the American Association of State Highway and Transportation Officials (AASHTO) Mechanistical-Empirical Pavement Design requires the development of a design procedure that can be used by the agencies and engineering consultants to design new and reconstructed rigid and flexible pavements. To calibrate the design procedure for a region, a large dataset representing the particular local conditions is needed. It includes traffic, climate, site material characteristics, performance requirements and historical data. The performance models were calibrated in North America using the Long Term Pavement Database Program (LTPP), therefore, the models must be calibrated to local conditions in order to …

Evaluation Of Key Geomechanical Aspects Of Shallow And Deep Geothermal Energy, Robert Alexander Caulk

Graduate College Dissertations and Theses

Geothermal energy has become a focal point of the renewable energy revolution. Both shallow and deep types of geothermal energy have the potential to offset carbon emissions, reduce energy costs, and stimulate the economy. Before widespread geothermal exploration and exploitation can occur, both shallow and deep technologies require improvement by theoretical and experimental investigations. This thesis investigated one aspect of both shallow and deep geothermal energy technologies. First, a group of shallow geothermal energy piles was modeled numerically. The model was constructed, calibrated, and validated using available data collected from full-scale in-situ experimental energy piles. Following calibration, the model was …

Variable Speed Limit Strategies To Reduce The Impacts Of Traffic Flow Breakdown At Recurrent Freeway Bottlenecks, Ali Darroudi

FIU Electronic Theses and Dissertations

Variable Speed Limit (VSL) strategies identify and disseminate dynamic speed limits that are determined to be appropriate based on prevailing traffic conditions, road surface conditions, and weather conditions. This dissertation develops and evaluates a shockwave-based VSL system that uses a heuristic switching logic-based controller with specified thresholds of prevailing traffic flow conditions. The system aims to improve operations and mobility at critical bottlenecks. Before traffic breakdown occurrence, the proposed VSL’s goal is to prevent or postpone breakdown by decreasing the inflow and achieving uniform distribution in speed and flow. After breakdown occurrence, the VSL system aims to dampen traffic congestion …

Operation Optimization And Water Quality Simulation Of Potable Water Distribution System, Xiongfei Xie

USF Tampa Graduate Theses and Dissertations

A potable water distribution system (WDS) consists of pipes, pumps, valves, storage tanks, control and supporting components. Traditionally, it has two basic functions. First, provides end users with potable water at sufficient pressures and good water quality. Second, provides sufficient pressure and flow for fire fighting. Currently, potable water is still the least expensive material for fire fighting. To accomplish these two goals, water utilities have to consider the integrity and security of the water network. As a result, this research selected three research topics that are closely related to the daily operation of water utilities and water quality simulation. …

The Pocketlai Smartphone App: An Alternative Method For Leaf Area Index Estimation, Roberto Confalonieri, Caterina Francone, Marco Foi

International Congress on Environmental Modelling and Software

The possibility of adopting the technology implemented in low-costs devices for the monitoring of biophysical processes is being increasingly explored by the scientific community. In the context of environmental studies, leaf area index (LAI) is one of the variables scientists and technicians are more interested in, since directly involved in radiation interception, and in crop response to water availability. An indirect method for leaf area index estimation was recently proposed and implemented in the smartphone app PocketLAI. The application uses the smartphone camera and the accelerometer to acquire images at 57.5° below the canopy while the user is rotating …

Investigating Parameter Sensitivity For Management In Snow-Driven Watersheds, Elizabeth Houle, Joseph Kasprzyk

International Congress on Environmental Modelling and Software

Recent projections of environmental change have shown possible variation to temperature and precipitation patterns due to climate change. In snowmelt-dominated watersheds, adapting to such environmental changes requires a detailed understanding of hydrological processes in addition to historical snow cover and streamflow data. Snow models are often incorporated as an additional component of hydrological modeling studies that inform research and operations management. However, previous research and parameter estimation approaches using snow models assume that parameters have a single optimal value and that each parameter is sensitive. This paper demonstrates that an improved understanding of snow model parameter sensitivity can aid in …

Application Of Parameter Estimation And Calibration Method For Car-Following Models, Md Rahman

All Theses

Both safety and the capacity of the roadway system are highly dependent on the car-following characteristics of drivers. Car-following theory describes the driver behavior of vehicles following other vehicles in a traffic stream. In the last few decades, many car-following models have been developed; however, studies are still needed to improve their accuracy and reliability.
Car-following models are a vital component of traffic simulation tools that attempt to mimic driver behavior in the real world. Microscopic traffic simulators, particularly car-following models, have been extensively used in current traffic engineering studies and safety research. These models are a vital component of …

Calibration Of Microscopic Traffic Flow Models Considering All Parameters Simultaneously, Victor Hugo Molano Paz

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study proposes a methodology to calibrate microscopic traffic flow simulation models. The proposed methodology has the capability to calibrate simultaneously all the calibration parameters as well as demand patterns for any network topology. These parameters include global and local parameters as well as driver behavior and vehicle performance parameters; all based on multiple performance measures, such as link counts and speeds. Demand patterns are included in the calibration framework in terms of turning volumes.

A Simultaneous Perturbation Stochastic Approximation (SPSA) algorithm is proposed to search for the vector of the model‟s parameters that minimizes the difference between actual and …

Understanding Operating Speed Variation Of Multilane Highways With New Access Density Definition And Simulation Outputs, Bing Huang

USF Tampa Graduate Theses and Dissertations

Traffic speed is generally considered a core issue in roadway safety. Previous studies show that faster travel is not necessarily associated with an increased risk of being involved in a crash. When vehicles travel at the same speed in the same direction (even high speeds, as on interstates), they are not passing one another and cannot collide as long as they maintain the same speed. Conversely, the frequency of crashes increases when vehicles are traveling at different rates of speed. There is no doubt that the greater speed variation is, the greater the number of interactions among vehicles is, resulting …

The Calibration, Validation, And Comparison Of Vissim Simulations Using The Two-Fluid Model, Jeremy Crowe

Electronic Theses and Dissertations

The microscopic traffic simulation program VISSIM is a powerful tool that has been used by transportation engineers and urban planners around the world. A VISSIM simulation is meant to depict the performance of the physical road network through the use of modeling tools and behavioral parameters. The process which gets the model to the point of matching real world conditions is called calibration and requires a means of relating the real world to the simulated world. The topic of this thesis discusses a new means of calibration using the two-fluid model. The two-fluid model is a macroscopic modeling technique which …

Improving Prediction Accuracy In Mechanistic-Empirical Pavement Design Guide, Scott Schram, Magdy Abdelrahman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Model calibration plays a fundamental role in the implementation of the mechanistic-empirical pavement design guide. The data used in the default calibration effort, which were afforded by the Long Term Pavement Performance (LTPP) database, have a network-level inference space. As implementation proceeds, state highway agencies may be inclined to calibrate at a local network level. However, with a focus on the calibration data set to local project-level conditions, model prediction error can be reduced further. Under this study, Nebraska Department of Roads Pavement Management System data were used to calibrate two design guide smoothness models at the local project level. …

Predicting Traffic Conditions At Indiana Signalized Intersections, Rafael I. Perez-Cartagena, Andrzej P. Tarko

JTRP Technical Reports

All of the methods for predicting traffic conditions at intersections provide default values for saturation flow rates and their adjustment factors, lost times, and other parameters. Because these parameters are difficult to measure, the use of the default values is a common practice and it can cause significant bias in the results if the actual local values are different. The main objective of this research was to investigate the variability of capacity and delay parameters used in engineering tools for predicting delays and for determining level of service (LOS) at signalized intersections in Indiana. The variability investigation produced Indiana default …

An Electronic Surveillance And Control System For The Management Of Traffic On The Borman Expressway, Part Ii: Calibrating A Simulation Model, Mu-Han Wang, Michael J. Cassidy

JTRP Technical Reports

The purpose of this project was to calibrate a freeway simulation model to emulate traffic operating conditions on the Borman Expressway in Northwest Indiana. To replicate Borman operating conditions, the project adopted Integrated Traffic Simulation (INTRAS), a microscopic, stochastic freeway simulation model. Appropriate input data were developed on geometric, traffic and driver behavior information, based on physical measurements and other available data. The model was calibrated and statistical analysis were conducted to validate the accuracy of the results.