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A Decision Support Model for Autonomous Trucks Strategies
Title
A Decision Support Model for Autonomous Trucks Strategies.
Creator
Mohamed, Ahmad Saeid Ammar, Yun, Hae-Bum, Chopra, Manoj, Sallam, Amr, University of Central Florida
Abstract / Description
We examined the potential to improve the movement of freight using Truck PlatooningLane strategies on limited access highways in the State of Florida. In the First part of thisresearch, we investigated the potential benefits from dedicating one lane from existinglanes for autonomous trucks only. In this regard, a general framework tool was developedto evaluate and compare different measurements (e.g., travel tim and emissions) to betterassist decision makers to determine the most effective...
Show moreWe examined the potential to improve the movement of freight using Truck PlatooningLane strategies on limited access highways in the State of Florida. In the First part of thisresearch, we investigated the potential benefits from dedicating one lane from existinglanes for autonomous trucks only. In this regard, a general framework tool was developedto evaluate and compare different measurements (e.g., travel tim and emissions) to betterassist decision makers to determine the most effective freight transportation strategy.Additionally, the travel time, level of service and emissions on Florida Strategic IntermodalSystem (SIS) were systematically analyzed using a VISSIM and MOVES simulation todetermine if it can be improved. For the scenarios simulated in this investigation, the inputincluded different patterns with a variety of peak hour volumes, truck percentages, speeds,and number of lanes. Additionally, the various total values of the resultant travel time,emissions and level of service for each SIS corridor were determined and calculated usinga General Linear Model and then tabulated to reveal input patterns. The results showed thata truck platooning lane can significantly reduce the travel time and emissions of trucks. Inthe second part, we proposed using a The Analytic Hierarchy Process (AHP) method toevaluate the potential benefits of building a new lane for autonomous trucks. The AHPmethod was developed to include all possible measurements that can assist decision makersto select the best autonomous truck policy. The results of the AHP model showed that thesafety criterion was significantly the most influential perspective per experts' opinions. Theresults showed that experts were more concerned about safety and environmentalconsiderations than the initial cost associated with building a new lane.
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Date Issued
2018
Identifier
CFE0007056, ucf:51983
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0007056
Multi-physics modeling of geomechanical systems with coupled hydromechanical behaviors
Title
Multi-physics modeling of geomechanical systems with coupled hydromechanical behaviors.
Creator
Mohamed, Ahmad Saeid Ammar, Yun, Hae-Bum, Chopra, Manoj, Sallam, Amr, University of Central Florida
Abstract / Description
Geotechnical structures under realistic field conditions are usually influenced with complex interactions of coupled hydromechanical behavior of porous materials. In many geotechnical applications, however, these important coupled interactions are ignored in their constitutive models. Under coupled hydromechanical behavior, stress in porous materials causes volumetric change in strain, which causes fluid diffusion; consequently, pore pressure dissipates through the pores that results in the...
Show moreGeotechnical structures under realistic field conditions are usually influenced with complex interactions of coupled hydromechanical behavior of porous materials. In many geotechnical applications, however, these important coupled interactions are ignored in their constitutive models. Under coupled hydromechanical behavior, stress in porous materials causes volumetric change in strain, which causes fluid diffusion; consequently, pore pressure dissipates through the pores that results in the consolidation of porous material. The objective of this research was to demonstrate the advantages of using hydromechanical models to estimate deformation and pore water pressure of porous materials by comparing with mechanical-only models. Firstly, extensive literature survey was conducted about hydro-mechanical models based on Biot's poroelastic concept. Derivations of Biot's poroelastic equations will be presented. To demonstrate the hydromechanical effects, a numerical model of poroelastic rock materials was developed using COMSOL, a commercialized multiphysics finite element software package, and compared with the analytical model developed by Wang (2000). Secondly, a series of sensitivity analyses was conducted to correlate the effect of poroelastic parameters on the behavior of porous material. The results of the sensitivity analysis show that porosity and Biot's coefficient has dominant contribution to porous material behavior. Thirdly, a coupled hydromechanical finite element model was developed for a real-world example of embankment consolidation. The simulation results show excellent agreement to field measurements of embankment settlement data.
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Date Issued
2013
Identifier
CFE0004722, ucf:49826
Format
Document (PDF)
PURL
http://purl.flvc.org/ucf/fd/CFE0004722