Physical Sciences and Mathematics | Open Access Articles

The Trolley Problem In Virtual Reality, Jungsu Pak, Ariane Guirguis, Nicholas Mirchandani, Scott Cummings, Uri Maoz

Student Scholar Symposium Abstracts and Posters

Would people react to the Trolley problem differently based on the medium? Immersive Virtual Reality Driving Simulator was used to examine participants respond to the trolley problem in a realistic and controlled simulated environment.

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Domain Adaptation In Unmanned Aerial Vehicles Landing Using Reinforcement Learning, Pedro Lucas Franca Albuquerque

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Landing an unmanned aerial vehicle (UAV) on a moving platform is a challenging task that often requires exact models of the UAV dynamics, platform characteristics, and environmental conditions. In this thesis, we present and investigate three different machine learning approaches with varying levels of domain knowledge: dynamics randomization, universal policy with system identification, and reinforcement learning with no parameter variation. We first train the policies in simulation, then perform experiments both in simulation, making variations of the system dynamics with wind and friction coefficient, then perform experiments in a real robot system with wind variation. We initially expected that providing …

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Individual Variation And Ecotypic Niches In Simulations Of The Impact Of Climatic Volatility, George P. Malanson, R. Justin Derose, Matthew F. Bekker

Wildland Resources Faculty Publications

Expectations of the impacts of climatic variation on species can depend on whether and how intraspecific variability is incorporated in models. Coefficients of variation from tree-ring records of Pinus albicaulis through time and across space were used to parameterize volatility and individuality, respectively. The records across sites were used to differentiate the average modes on an environmental gradient for Gaussian fitness of ecotypic niches, and to add further individual variation in mode and standard deviation of these functions in individual-based Monte Carlo simulations of reproduction and mortality with inheritance of individual variability. Ecotypic gamma and Shannon diversity decreased with volatility …

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Development Of An Autonomous Aerial Toolset For Agricultural Applications, Terrance Life

Mahurin Honors College Capstone Experience/Thesis Projects

According to the United Nations, the world population is expected to grow from its current 7 billion to 9.7 billion by the year 2050. During this time, global food demand is also expected to increase by between 59% and 98% due to the population increase, accompanied by an increasing demand for protein due to a rising standard of living throughout developing countries. [1] Meeting this increase in required food production using present agricultural practices would necessitate a similar increase in farmland; a resource which does not exist in abundance. Therefore, in order to meet growing food demands, new methods will …

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Combining Geographic Information Systems And Agent-Based Models In Archaeology: Part 2 Of 3, Benjamin Davies, Iza Romanowska, Kathryn Harris, Stefani Crabtree

Environment and Society Faculty Publications

Archaeologists are using spatial data in increasingly sophisticated analyses and invoking more explicit considerations of space in their interpretations. Geographic information systems (GIS) have become standard technology for professional archaeologists in the collection and management of spatial data. Many calls have been made to develop and adapt digital geospatial technologies for interpretation and understanding past social dynamics, but this has been limited to some extent by the static nature of map-oriented GIS approaches. Here, we illustrate how coupling GIS with agent-based modeling (ABM) can assist with more dynamic explorations of past uses of space and geospatial phenomena.

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Neuroprotective Effects Of Melatonin And Celecoxib Against Ethanol-Induced Neurodegeneration: A Computational And Pharmacological Approach, Lina T. Al Kury, Alam Zeb, Zain Ul Abidin, Nadeem Irshad, Imran Malik, Arooj Mohsin Alvi, Atif Ali Khan Khalil, Sareer Ahmad, Muhammad Faheem, Arif Ullah Khan, Fawad Ali Shah, Shupeng Li

All Works

© 2019 Al Kury et al. This work is published and licensed by Dove Medical Press Limited. Purpose: Melatonin and celecoxib are antioxidants and anti-inflammatory agents that exert protective effects in different experimental models. In this study, the neuroprotective effects of melatonin and celecoxib were demonstrated against ethanol-induced neuronal injury by in silico, morphological, and biochemical approaches. Methods: For the in silico study, 3-D structures were constructed and docking analysis performed. For in vivo studies, rats were treated with ethanol, melatonin, and celecoxib. Brain samples were collected for biochemical and morphological analysis. Results: Homology modeling was performed to build 3-D …

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Local Lagged Adapted Generalized Method Of Moments: An Innovative Estimation And Forecasting Approach And Its Applications., Olusegun Michael Otunuga, Gandaram S. Ladde, Nathan G. Ladde

Mathematics Faculty Research

In this work, an attempt is made to apply the Local Lagged Adapted Generalized Method of Moments (LLGMM) to estimate state and parameters in stochastic differential dynamic models. The development of LLGMM is motivated by parameter and state estimation problems in continuous-time nonlinear and non-stationary stochastic dynamic model validation problems in biological, chemical, engineering, energy commodity markets, financial, medical, military, physical sciences and social sciences. The byproducts of this innovative approach (LLGMM) are the balance between model specification and model prescription of continuous-time dynamic process and the development of discrete-time interconnected dynamic model of local sample mean and variance statistic …

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A Species-Specific Individual-Based Simulation Model Of Mixed Mangrove Forest Stands, Ian Estacio, Khristoffer Ryan Quinton, Edgardo Macatulad, Severino G. Salmo Iii

Environmental Science Faculty Publications

A species-specific spatially explicit individual-based model has been developed to simulate the development of mixed mangrove forest stands featuring eight species. The model is a forest stand model that forecasts mangrove forest development in a 50 m x 50 m plot by simulating the recruitment, growth, and mortality of individual mangrove trees. Species-specific growth rates, shade responses, and salinity responses of each species were incorporated to observe differences in forest structure given different salinity conditions. The model used a modified Field of Neighborhood (FON) approach that considers species-specific responses to shading and a salinity response function that considers the species-specific …

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Personal Universes: A Solution To The Multi-Agent Value Alignment Problem, Roman V. Yampolskiy

Faculty Scholarship

AI Safety researchers attempting to align values of highly capable intelligent systems with those of humanity face a number of challenges including personal value extraction, multi-agent value merger and finally in-silico encoding. State-of-the-art research in value alignment shows difficulties in every stage in this process, but merger of incompatible preferences is a particularly difficult challenge to overcome. In this paper we assume that the value extraction problem will be solved and propose a possible way to implement an AI solution which optimally aligns with individual preferences of each user. We conclude by analyzing benefits and limitations of the proposed approach.

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Instability Of Flux Flow And Production Of Vortex-Antivortex Pairs By Current-Driven Josephson Vortices In Layered Superconductors, Ahmad Sheikhzada, Alex Gurevich

Physics Faculty Publications

We report numerical simulations of the nonlinear dynamics of Josephson vortices driven by strong dc currents in layered superconductors. Dynamic equations for interlayer phase differences in a stack of coupled superconducting layers were solved to calculate a drag coefficient η(J) of the vortex as a function of the perpendicular dc current density J. It is shown that Cherenkov radiation produced by a moving vortex causes significant radiation drag increasing η(v) at high vortex velocities v and striking instabilities of driven Josephson vortices moving faster than a terminal v_c. The steady-state flux flow breaks down at ν > v …

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Equilibria And Synchrotron Stability In Two Energy Storage Rings, B. Dhital, Jean R. Delayen, Y. S. Derbenev, D. Douglas, Geoffrey A. Krafft, F. Lin, B. Morozov, Y. Zhang

Physics Faculty Publications

In a dual energy storage ring, the electron beam passes through two loops at markedly different energies E_{L}, and E_{H}, i.e., energies for low energy loop and high energy loop respectively. These loops use a common beamline where a superconducting linac at first accelerates the beam from EL to EH and then decelerates the beam from EH to EL in the next pass. There are two basic solutions to the equilibrium problems possible, i.e., ’Storage Ring’ (SR) equilibrium and ’Energy Recovery Linac’ (ERL) equilibrium. SR equilibrium mode more resembles the usual single loop storage ring with strong synchrotron motion and …

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Electron-Ion Collider Performance Studies With Beam Synchronization Via Gear-Change, I. Neththikumara, Geoffrey A. Krafft, Y. Roblin, Balša Terzić

Physics Faculty Publications

Beam synchronization of the future electron-ion collider (EIC) is studied with introducing different bunch numbers in the two colliding beams. This allows non-pairwise collisions between the bunches of the two beams and is known as "gear-change", whereby one bunch of the first beam collides with all other bunches of the second beam, one at a time. Here we report on the study of how the beam dynamics of the Jefferson Lab Electron Ion collider concept is affected by the gear change. For this study, we use the new GPU-based code (GHOST). It features symplectic one-turn maps for particle tracking and …

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Beam-Beam Effect: Crab Dynamics Calculation In Jleic, He Huang, Vasiliy Morozov, Yves Roblin, Amy Sy, Fanglei Lin, Yuhong Zhang, Balša Terzić, Salvador Sosa, Isurumali Neththikumara

Physics Faculty Publications

The electron and ion beams of a future Electron Ion Collider (EIC) must collide at an angle for detection, machine and engineering design reasons. To avoid associated luminosity reduction, a local crabbing scheme is used where each beam is crabbed before collision and de-crabbed after collision. The crab crossing scheme then provides a head-on collision for beams with a non-zero crossing angle. We develop a framework for accurate simulation of crabbing dynamics with beam-beam effects by combining symplectic particle tracking codes with a beam-beam model based on the Bassetti-Erskine analytic solution. We present simulation results using our implementation of such …

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Physical Sciences and Mathematics Commons^™

Full-Text Articles in Physical Sciences and Mathematics

The Trolley Problem In Virtual Reality, Jungsu Pak, Ariane Guirguis, Nicholas Mirchandani, Scott Cummings, Uri Maoz

Student Scholar Symposium Abstracts and Posters

Domain Adaptation In Unmanned Aerial Vehicles Landing Using Reinforcement Learning, Pedro Lucas Franca Albuquerque

Department of Computer Science and Engineering: Dissertations, Theses, and Student Research

Individual Variation And Ecotypic Niches In Simulations Of The Impact Of Climatic Volatility, George P. Malanson, R. Justin Derose, Matthew F. Bekker

Wildland Resources Faculty Publications

Development Of An Autonomous Aerial Toolset For Agricultural Applications, Terrance Life

Mahurin Honors College Capstone Experience/Thesis Projects

Combining Geographic Information Systems And Agent-Based Models In Archaeology: Part 2 Of 3, Benjamin Davies, Iza Romanowska, Kathryn Harris, Stefani Crabtree

Environment and Society Faculty Publications

All Works

Local Lagged Adapted Generalized Method Of Moments: An Innovative Estimation And Forecasting Approach And Its Applications., Olusegun Michael Otunuga, Gandaram S. Ladde, Nathan G. Ladde

Mathematics Faculty Research

A Species-Specific Individual-Based Simulation Model Of Mixed Mangrove Forest Stands, Ian Estacio, Khristoffer Ryan Quinton, Edgardo Macatulad, Severino G. Salmo Iii

Environmental Science Faculty Publications

Personal Universes: A Solution To The Multi-Agent Value Alignment Problem, Roman V. Yampolskiy

Faculty Scholarship

Instability Of Flux Flow And Production Of Vortex-Antivortex Pairs By Current-Driven Josephson Vortices In Layered Superconductors, Ahmad Sheikhzada, Alex Gurevich

Physics Faculty Publications

Equilibria And Synchrotron Stability In Two Energy Storage Rings, B. Dhital, Jean R. Delayen, Y. S. Derbenev, D. Douglas, Geoffrey A. Krafft, F. Lin, B. Morozov, Y. Zhang

Physics Faculty Publications

Electron-Ion Collider Performance Studies With Beam Synchronization Via Gear-Change, I. Neththikumara, Geoffrey A. Krafft, Y. Roblin, Balša Terzić

Physics Faculty Publications

Beam-Beam Effect: Crab Dynamics Calculation In Jleic, He Huang, Vasiliy Morozov, Yves Roblin, Amy Sy, Fanglei Lin, Yuhong Zhang, Balša Terzić, Salvador Sosa, Isurumali Neththikumara

Physics Faculty Publications