Open Access. Powered by Scholars. Published by Universities.®
Physical Sciences and Mathematics Commons™
Open Access. Powered by Scholars. Published by Universities.®
- Discipline
-
- Computer Sciences (389)
- Engineering (262)
- Computer Engineering (182)
- Numerical Analysis and Scientific Computing (162)
- Artificial Intelligence and Robotics (159)
-
- Operations Research, Systems Engineering and Industrial Engineering (148)
- Systems Science (137)
- Physics (120)
- Statistics and Probability (110)
- Life Sciences (64)
- Earth Sciences (57)
- Social and Behavioral Sciences (57)
- Mathematics (53)
- Applied Statistics (49)
- Applied Mathematics (48)
- Environmental Sciences (40)
- Plant Sciences (39)
- Soil Science (38)
- Agronomy and Crop Sciences (37)
- Plant Biology (36)
- Agricultural Science (34)
- Plant Pathology (34)
- Weed Science (34)
- Engineering Physics (33)
- Statistical Theory (32)
- Electrical and Computer Engineering (29)
- Medicine and Health Sciences (28)
- Astrophysics and Astronomy (24)
- Oceanography and Atmospheric Sciences and Meteorology (24)
- Institution
-
- China Simulation Federation (135)
- Old Dominion University (69)
- University of Kentucky (45)
- Wayne State University (28)
- Utah State University (27)
-
- California Polytechnic State University, San Luis Obispo (22)
- TÜBİTAK (18)
- Dartmouth College (17)
- Brigham Young University (16)
- University of Nebraska - Lincoln (15)
- Air Force Institute of Technology (14)
- Prairie View A&M University (12)
- University of South Florida (12)
- Clemson University (11)
- Louisiana State University (11)
- Missouri University of Science and Technology (11)
- University of Arkansas, Fayetteville (11)
- Embry-Riddle Aeronautical University (10)
- University of Nevada, Las Vegas (10)
- Edith Cowan University (9)
- Purdue University (9)
- Technological University Dublin (9)
- City University of New York (CUNY) (8)
- Syracuse University (8)
- Virginia Commonwealth University (8)
- Marshall University (7)
- Singapore Management University (7)
- East Tennessee State University (6)
- New Jersey Institute of Technology (6)
- The Texas Medical Center Library (6)
- Publication Year
- Publication
-
- Journal of System Simulation (135)
- Theses and Dissertations (46)
- IGC Proceedings (1977-2023) (34)
- Physics Faculty Publications (30)
- Journal of Modern Applied Statistical Methods (25)
-
- Dartmouth Scholarship (15)
- Electronic Theses and Dissertations (14)
- Applications and Applied Mathematics: An International Journal (AAM) (12)
- Master's Theses (11)
- Turkish Journal of Electrical Engineering and Computer Sciences (11)
- USF Tampa Graduate Theses and Dissertations (11)
- All Graduate Theses and Dissertations, Spring 1920 to Summer 2023 (8)
- Faculty Publications (8)
- Dissertations (7)
- LSU Doctoral Dissertations (7)
- Research Collection School Of Computing and Information Systems (7)
- All Dissertations (6)
- School of Computing: Dissertations, Theses, and Student Research (6)
- UNLV Theses, Dissertations, Professional Papers, and Capstones (6)
- All Graduate Plan B and other Reports, Spring 1920 to Spring 2023 (5)
- All Theses (5)
- Browse all Theses and Dissertations (5)
- Computer Science Faculty Research & Creative Works (5)
- International Conference on Hydroinformatics (5)
- VMASC Publications (5)
- Articles (4)
- Biosystems and Agricultural Engineering Faculty Publications (4)
- Computational Modeling & Simulation Engineering Theses & Dissertations (4)
- Doctoral Dissertations (4)
- Engineering Management & Systems Engineering Faculty Publications (4)
- Publication Type
- File Type
Articles 121 - 150 of 784
Full-Text Articles in Physical Sciences and Mathematics
Vanet Applications Under Loss Scenarios & Evolving Wireless Technology, Adil Alsuhaim
Vanet Applications Under Loss Scenarios & Evolving Wireless Technology, Adil Alsuhaim
All Dissertations
In this work we study the impact of wireless network impairment on the performance of VANET applications such as Cooperative Adaptive Cruise Control (CACC), and other VANET applications that periodically broadcast messages. We also study the future of VANET application in light of the evolution of radio access technologies (RAT) that are used to exchange messages. Previous work in the literature proposed fallback strategies that utilizes on-board sensors to recover in case of wireless network impairment, those methods assume a fixed time headway value, and do not achieve string stability. In this work, we study the string stability of a …
Analyzing And Computing Complete Solution For Dots And Boxes Game, Carl Mcaninch
Analyzing And Computing Complete Solution For Dots And Boxes Game, Carl Mcaninch
Undergraduate Theses and Capstone Projects
This thesis improves a process that analyzes all the states of a game of Dots and Boxes. We use retrograde analysis and simulations to create a solution that provides significant performance improvements over our previous best solution. Expanding upon a previous 4x4 solution using rotations, reflections, better optimization, and cloud computing to limit the processing time and gather more data efficiently. We compute a file and the number of states associated with each file and process every state starting with a completely filled board. We optimized the data for cloud computing by running simulations to find the most efficient number …
Statistical Approach To Quantifying Interceptability Of Interaction Scenarios For Testing Autonomous Surface Vessels, Benjamin E. Hargis, Yiannis E. Papelis
Statistical Approach To Quantifying Interceptability Of Interaction Scenarios For Testing Autonomous Surface Vessels, Benjamin E. Hargis, Yiannis E. Papelis
Modeling, Simulation and Visualization Student Capstone Conference
This paper presents a probabilistic approach to quantifying interceptability of an interaction scenario designed to test collision avoidance of autonomous navigation algorithms. Interceptability is one of many measures to determine the complexity or difficulty of an interaction scenario. This approach uses a combined probability model of capability and intent to create a predicted position probability map for the system under test. Then, intercept-ability is quantified by determining the overlap between the system under test probability map and the intruder’s capability model. The approach is general; however, a demonstration is provided using kinematic capability models and an odometry-based intent model.
Enhancing Pedestrian-Autonomous Vehicle Safety In Low Visibility Scenarios: A Comprehensive Simulation Method, Zizheng Yan, Yang Liu, Hong Yang
Enhancing Pedestrian-Autonomous Vehicle Safety In Low Visibility Scenarios: A Comprehensive Simulation Method, Zizheng Yan, Yang Liu, Hong Yang
Modeling, Simulation and Visualization Student Capstone Conference
Self-driving cars raise safety concerns, particularly regarding pedestrian interactions. Current research lacks a systematic understanding of these interactions in diverse scenarios. Autonomous Vehicle (AV) performance can vary due to perception accuracy, algorithm reliability, and environmental dynamics. This study examines AV-pedestrian safety issues, focusing on low visibility conditions, using a co-simulation framework combining virtual reality and an autonomous driving simulator. 40 experiments were conducted, extracting surrogate safety measures (SSMs) from AV and pedestrian trajectories. The results indicate that low visibility can impair AV performance, increasing conflict risks for pedestrians. AV algorithms may require further enhancements and validations for consistent safety performance …
A Simulation Of The Impacts Of Climate Change On Civil Aircraft Takeoff Performance, Thomas D. Pellegrin
A Simulation Of The Impacts Of Climate Change On Civil Aircraft Takeoff Performance, Thomas D. Pellegrin
Doctoral Dissertations and Master's Theses
Climate change affects the near-surface environmental conditions that prevail at airports worldwide. Among these, air density and headwind speed are major determinants of takeoff performance, and their sensitivity to global warming carries potential operational and economic implications for the commercial air transport industry. Previous archival and prospective research observed a weakening in headwind strength and predicted an increase in near-surface temperatures, respectively, resulting in an increase in takeoff distances and weight restrictions. The main purpose of the present study was to update and generalize the extant prospective research using a more representative sample of worldwide airports, a wider range of …
V2v And V2i Based Safety And Platooning Algorithms For Connected And Autonomous Vehicles, Omkar Dokur
V2v And V2i Based Safety And Platooning Algorithms For Connected And Autonomous Vehicles, Omkar Dokur
USF Tampa Graduate Theses and Dissertations
Connected Vehicles (CVs) make transportation safe by communicating with vehicles and the infrastructure in their neighborhood. CVs are embedded with onboard units (OBUs) which transmit basic safety messages (BSMs) containing the location, heading, and velocity information of the vehicle using either Dedicated Short-Range Communications (DSRC) or Cellular Vehicle-to-Everything (C-V2X) technology. These BSMs can be used to warn drivers using various vehicle-to-vehicle (V2V) or vehicle-to-infrastructure (V2I) applications. Along with these applications, CV technology also gives rise to cooperative vehicular driving applications such as platooning. A group of vehicles can negotiate and drive jointly close to each other in a cooperative manner …
Conformational Dynamics And Free Energy Studies Of Dna And Other Biomolecules, Paul B. Orndorff
Conformational Dynamics And Free Energy Studies Of Dna And Other Biomolecules, Paul B. Orndorff
USF Tampa Graduate Theses and Dissertations
This work uses molecular dynamics simulations and enhanced sampling methods to investigate both the qualitative and quantitative properties of biomolecular systems. Conformational dynamics are critical in the study of biomolecular systems. Application of computer simulations to study dynamics of biomolecular systems allows for motions to be readily investigated at a resolution not possible in experimental techniques. In this work, the dynamics of uracil damaged and undamaged DNA is studied via molecular dynamics simulations. Uracil results in DNA from either misincorporation in the replication process or through spontaneous deamination of cytosine, and its presence in DNA can lead to mutations in …
Analysis Of Energy Transfer Among Background Flow, Gravity Waves And Turbulence In The Mesopause Region In The Process Of Gravity Wave Breaking From A High-Resolution Atmospheric Model, Fan Yang, Alan Z. Liu, Christopher J. Heale, Jonathan B. Snively, Wenjun Dong, Thomas Lund
Analysis Of Energy Transfer Among Background Flow, Gravity Waves And Turbulence In The Mesopause Region In The Process Of Gravity Wave Breaking From A High-Resolution Atmospheric Model, Fan Yang, Alan Z. Liu, Christopher J. Heale, Jonathan B. Snively, Wenjun Dong, Thomas Lund
Publications
We conducted an analysis of the process of GW breaking from an energy perspective using the output from a high-resolution compressible atmospheric model. The investigation focused on the energy conversion and transfer that occur during the GW breaking. The total change in kinetic energy and the amount of energy converted to internal energy and potential energy within a selected region were calculated. Prior to GW breaking, part of the potential energy is converted into kinetic energy, most of which is transported out of the chosen region. After the GW breaks and turbulence develops, part of the potential energy is converted …
Adaptation Of Network Flow Problems For Course Of Action Generation, Alexander N. Stephens
Adaptation Of Network Flow Problems For Course Of Action Generation, Alexander N. Stephens
Theses and Dissertations
This thesis introduces two methods to generate Courses of Action (COA) in distributed warfare scenarios: the Wargaming Commodity Course of Action Automated Method Under Uncertainty (WCCAAM-U2) and Dynamic Transshipment Problem (DTP)-generated COAs. Previous work by Deberry et al. used a Multi-Commodity Flow Problem (MCFP) to generate COAs for single-period wargame scenarios with known enemy force amounts. In WCCAAM-U2, we adapt an MCFP to work in situations where only intelligence estimates of enemy forces are known. Compared to two other COA-generation methods, the WCCAAAM-U2 COA outperforms the next highest-performing COA by 307% when compared by a ratio of objective success rate …
Development Of A Model Simulating The Impact Of Management Strategies On Production From Beef Cattle Farming Systems Based On Permanent Pasture, M. Jouven, R. Baumont
Development Of A Model Simulating The Impact Of Management Strategies On Production From Beef Cattle Farming Systems Based On Permanent Pasture, M. Jouven, R. Baumont
IGC Proceedings (1977-2023)
Grazing systems in Europe increasingly have to meet environmental objectives, which influence management strategies. A deterministic model describing farming system dynamics is being developed in order to elucidate interactions between nature-friendly management practices, as for example late (after flowering) hay harvest or moderate stocking rate, and agricultural output.
A New Agro-Meteorological Simulation Model For Predicting Daily Grass Growth Rates Across Ireland, R. P. O. Schulte
A New Agro-Meteorological Simulation Model For Predicting Daily Grass Growth Rates Across Ireland, R. P. O. Schulte
IGC Proceedings (1977-2023)
Grass growth rates and herbage yields depend on weather conditions, soil characteristics and grassland management and differ from year to year and from site to site. In the past, grass growth has been predicted using both mechanistic and statistical models. The accuracy of mechanistic models is commonly insufficient for practical application, while statistical models generally apply to one test site only (e.g. Han et al., 2003). In this paper a semi-empirical grass growth model is presented which is numerically accurate, but which can be applied to contrasting sites across Ireland at the same time.
Enhancing Grasslands Education With Decision Support Tools, H. G. Daily, J. M. Scott, J. M. Reid
Enhancing Grasslands Education With Decision Support Tools, H. G. Daily, J. M. Scott, J. M. Reid
IGC Proceedings (1977-2023)
We have successfully used Decision Support Tools (DST) relevant to the management of grazing enterprises to enhance problem solving skills of undergraduates in Australia. Tools such as GrassGro™ (Moore et al., 1997) and GrazFeed™ (Freer et al., 1997) are accessed from a central server by authorised users at many widely dispersed Universities across Australia using remote access to thin-client technology via an Internet portal. This has been supplemented with training for lecturers. Experience in developing appropriate teaching and learning materials and the reliable delivery of simulation software to many clients has enhanced learning outcomes at tertiary level. We …
Using The Grassgro Decision Support Tool To Evaluate The Response In Grazing Systems To Pasture Legume Or A Grass Cultivar With Improved Nutritive Value, H. Dove, J. R. Donnelly
Using The Grassgro Decision Support Tool To Evaluate The Response In Grazing Systems To Pasture Legume Or A Grass Cultivar With Improved Nutritive Value, H. Dove, J. R. Donnelly
IGC Proceedings (1977-2023)
Decision support tools (DST) based on models of grazing systems allow the evaluation of changes in enterprise management on productivity and profitability. The Grassgro DST (Moore et al., 1997) uses historical weather data on a daily time step to simulate pasture growth and the resultant productivity of either grazing sheep or cattle. Different pasture species are represented within a parameter set that describes the response of pasture species to their environment. Manipulation of these parameters provides a means of evaluating, a priori, the likely responses of livestock production to ‘improved cultivars’. We report the results of simulations conducted …
Pasture Land Management System Decision Support Software, G. E. Groover, S. R. Smith, N. D. Stone, J. J. Venuto, J. M. Galbraith
Pasture Land Management System Decision Support Software, G. E. Groover, S. R. Smith, N. D. Stone, J. J. Venuto, J. M. Galbraith
IGC Proceedings (1977-2023)
Controlled or rotational grazing provides benefits to producers and society through profitable and sound management of grazing land and livestock. Pasture land management system (PLMS) is a decision support system developed to help university, government, and professionals provide technical pasture management assistance to beef and dairy producers. The PLMS focuses on the balance between seasonal forage supply and nutrient demand in a dairy or beef cattle operation. It allows users to explore and compare alternatives (dividing fields into multiple paddocks, changing stocking rates, and forage species) through a visual display and embedded simulation. Users enter a description of the farm …
Grass Growth Modelling: To Increase Understanding And Aid Decision Making On-Farm, P. D. Barrett, A. S. Laidlaw
Grass Growth Modelling: To Increase Understanding And Aid Decision Making On-Farm, P. D. Barrett, A. S. Laidlaw
IGC Proceedings (1977-2023)
Key points
-
Crop and grass growth models have been developed over the last 50 years, or so, but general appreciation of their benefits and potential has been recognised only relatively recently. The most popular application of grass growth models has traditionally been for knowledge understanding.
-
There is growing awareness of the potential of models in decision support systems (DSS) applications to aid pasture management and grassland budgeting on dairy farms.
-
Although some models have been developed for DSS, their widespread uptake in industry has been slow; challenges still exist which need to be addressed in order to improve their precision …
Quantum Computing And Its Applications In Healthcare, Vu Giang
Quantum Computing And Its Applications In Healthcare, Vu Giang
OUR Journal: ODU Undergraduate Research Journal
This paper serves as a review of the state of quantum computing and its application in healthcare. The various avenues for how quantum computing can be applied to healthcare is discussed here along with the conversation about the limitations of the technology. With more and more efforts put into the development of these computers, its future is promising with the endeavors of furthering healthcare and various other industries.
Acceleration Of U.S. Southeast And Gulf Coast Sea-Level Rise Amplified By Internal Climate Variability, Sönke Dangendorf, Noah Hendricks, Qiang Sun, John Klinck, Tal Ezer, Thomas Frederikse, Francisco M. Calafat, Thomas Wahl, Torbjörn E. Törnqvist
Acceleration Of U.S. Southeast And Gulf Coast Sea-Level Rise Amplified By Internal Climate Variability, Sönke Dangendorf, Noah Hendricks, Qiang Sun, John Klinck, Tal Ezer, Thomas Frederikse, Francisco M. Calafat, Thomas Wahl, Torbjörn E. Törnqvist
CCPO Publications
While there is evidence for an acceleration in global mean sea level (MSL) since the 1960s, its detection at local levels has been hampered by the considerable influence of natural variability on the rate of MSL change. Here we report a MSL acceleration in tide gauge records along the U.S. Southeast and Gulf coasts that has led to rates (>10 mm yr−1 since 2010) that are unprecedented in at least 120 years. We show that this acceleration is primarily induced by an ocean dynamic signal exceeding the externally forced response from historical climate model simulations. However, when the …
Stochastic Optimization To Reduce Aircraft Taxi-In Time At Igia, New Delhi, Rajib Das, Saileswar Ghosh, Rajendra Desai, Pijus Kanti Bhuin, Stuti Agarwal
Stochastic Optimization To Reduce Aircraft Taxi-In Time At Igia, New Delhi, Rajib Das, Saileswar Ghosh, Rajendra Desai, Pijus Kanti Bhuin, Stuti Agarwal
International Journal of Aviation, Aeronautics, and Aerospace
Since there is an uncertainty in the arrival times of flights, pre-scheduled allocation of runways and stands and the subsequent first-come-first-served treatment results in a sub-optimal allocation of runways and stands, this is the prime reason for the unusual delays in taxi-in times at IGIA, New Delhi.
We simulated the arrival pattern of aircraft and utilized stochastic optimization to arrive at the best runway-stands allocation for a day. Optimization is done using a GRG Non-Linear algorithm in the Frontline Systems Analytic Solver platform. We applied this model to eight representative scenarios of two different days. Our results show that without …
Long-Range Aceo Phenomena In Microfluidic Channel, Diganta Dutta, Keifer Smith, Xavier Palmer
Long-Range Aceo Phenomena In Microfluidic Channel, Diganta Dutta, Keifer Smith, Xavier Palmer
Electrical & Computer Engineering Faculty Publications
Microfluidic devices are increasingly utilized in numerous industries, including that of medicine, for their abilities to pump and mix fluid at a microscale. Within these devices, microchannels paired with microelectrodes enable the mixing and transportation of ionized fluid. The ionization process charges the microchannel and manipulates the fluid with an electric field. Although complex in operation at the microscale, microchannels within microfluidic devices are easy to produce and economical. This paper uses simulations to convey helpful insights into the analysis of electrokinetic microfluidic device phenomena. The simulations in this paper use the Navier–Stokes and Poisson Nernst–Planck equations solved using COMSOL …
The Wacdt, A Modern Vigilance Task For Network Defense, Oliver A. Guidetti, Craig Speelman, Peter Bouhlas
The Wacdt, A Modern Vigilance Task For Network Defense, Oliver A. Guidetti, Craig Speelman, Peter Bouhlas
Research outputs 2022 to 2026
Vigilance decrement refers to a psychophysiological decline in the capacity to sustain attention to monotonous tasks after prolonged periods. A plethora of experimental tasks exist for researchers to study vigilance decrement in classic domains such as driving and air traffic control and baggage security; however, the only cyber vigilance tasks reported in the research literature exist in the possession of the United States Air Force (USAF). Moreover, existent cyber vigilance tasks have not kept up with advances in real-world cyber security and consequently no longer accurately reflect the cognitive load associated with modern network defense. The Western Australian Cyber Defense …
Integration Of Omnet++ Into A Networking Course In An Electrical Engineering Technology Program, Murat Kuzlu, Brian Emmanuel Tamayo, Salih Sarp, Otilia Popescu, Vukica M. Jovanovic
Integration Of Omnet++ Into A Networking Course In An Electrical Engineering Technology Program, Murat Kuzlu, Brian Emmanuel Tamayo, Salih Sarp, Otilia Popescu, Vukica M. Jovanovic
Engineering Technology Faculty Publications
Networking courses are an integral part of electrical engineering technology programs as the majority of electronics in the modern day are required to communicate with each other. They are also getting more attention in manufacturing engineering technology programs because of the development of emerging technologies in Industry 4.0 arena. From laptops, computers, cellphones, modern day vehicles and smart refrigerators, these devices require a certain level of networking in order to communicate with other devices, whether it be locally, or even across the other side of the world. The objective of networking courses in an electrical engineering program is to demonstrate …
A Structured Narrative Prompt For Prompting Narratives From Large Language Models: Sentiment Assessment Of Chatgpt-Generated Narratives And Real Tweets, Christopher J. Lynch, Erik J. Jensen, Virginia Zamponi, Kevin O'Brien, Erika Frydenlund, Ross Gore
A Structured Narrative Prompt For Prompting Narratives From Large Language Models: Sentiment Assessment Of Chatgpt-Generated Narratives And Real Tweets, Christopher J. Lynch, Erik J. Jensen, Virginia Zamponi, Kevin O'Brien, Erika Frydenlund, Ross Gore
VMASC Publications
Large language models (LLMs) excel in providing natural language responses that sound authoritative, reflect knowledge of the context area, and can present from a range of varied perspectives. Agent-based models and simulations consist of simulated agents that interact within a simulated environment to explore societal, social, and ethical, among other, problems. Simulated agents generate large volumes of data and discerning useful and relevant content is an onerous task. LLMs can help in communicating agents' perspectives on key life events by providing natural language narratives. However, these narratives should be factual, transparent, and reproducible. Therefore, we present a structured narrative prompt …
Dynamic Predictions Of Thermal Heating And Cooling Of Silicon Wafer, Hitesh Kumar
Dynamic Predictions Of Thermal Heating And Cooling Of Silicon Wafer, Hitesh Kumar
Master's Projects
Neural Networks are now emerging in every industry. All the industries are trying their best to exploit the benefits of neural networks and deep learning to make predictions or simulate their ongoing process with the use of their generated data. The purpose of this report is to study the heating pattern of a silicon wafer and make predictions using various machine learning techniques. The heating of the silicon wafer involves various factors ranging from number of lamps, wafer properties and points taken in consideration to capture the heating temperature. This process involves dynamic inputs which facilitates the heating of the …
Molecular Biofilm Inhibitors On Noble Metal Surfaces, Mahamadu Tiah Mahama
Molecular Biofilm Inhibitors On Noble Metal Surfaces, Mahamadu Tiah Mahama
Dissertations and Theses
Biofilms are the state microorganisms on surfaces which negatively impact many of processes taking place on them. For example, most microbial infections are attributed to biofilm forma- tion, with bacteria in biofilms exhibiting an antibiotic resistance several orders of magnitude than planktonic bacteria. Therefore, developing antibiofilm agents and understanding their mechanism of inhibition is essential. Citrate functionalized gold nanoparticles are well known for their an- tibiofilm properties. Recently, hybrid bisphosphonate polyoxovanadate gold nanoparticles showed a great potential to inhibit both gram-negative and gram-positive bacteria biofilm formation. How- ever, it is unknown how this species interacts with the metal surface, its …
Statistical Models For Decision-Making In Professional Soccer, Sean Hellingman
Statistical Models For Decision-Making In Professional Soccer, Sean Hellingman
Theses and Dissertations (Comprehensive)
As soccer is widely regarded as the most popular sport in the world there is high interest in methods of improving team performances. There are many ways teams and individual athletes can influence their own performances during competition. This thesis focuses on developing statistical methodologies for improving competition-based decision-making for soccer so as to allow professional soccer teams to make better informed decisions regarding player selection and in-game decision-making.
To properly capture the dynamic actions of professional soccer, Markov chains with increasing complexity are proposed. These models allow for the inclusion of potential changes in the process caused by goals …
Quantum Efficiency Enhancement In Simulated Nanostructured Negative Electron Affinity Gaas Photocathodes, Md Aziz Ar Rahman, Shukui Zhang, Hani E. Elsayed-Ali
Quantum Efficiency Enhancement In Simulated Nanostructured Negative Electron Affinity Gaas Photocathodes, Md Aziz Ar Rahman, Shukui Zhang, Hani E. Elsayed-Ali
Physics Faculty Publications
Nanostructured negative electron affinity GaAs photocathodes for a polarized electron source are studied using finite difference time domain optical simulation. The structures studied are nanosquare columns, truncated nanocones, and truncated nanopyramids. Mie-type resonances in the 700–800 nm waveband, suitable for generation of polarized electrons, are identified. At resonance wavelengths, the nanostructures can absorb up to 99% of the incident light. For nanosquare columns and truncated nanocones, the maximum quantum efficiency (QE) at 780 nm obtained from simulation is 27%, whereas for simulated nanopyramids, the QE is ∼21%. The high photocathode quantum efficiency is due to the shift of Mie resonance …
Numerical Calculations Of Superheating Field In Superconductors With Nanostructured Surfaces, M.R.P. Walive Pathiranage, A. Gurevich
Numerical Calculations Of Superheating Field In Superconductors With Nanostructured Surfaces, M.R.P. Walive Pathiranage, A. Gurevich
Physics Faculty Publications
We report calculations of a dc superheating field Hs in superconductors with nanostructured surfaces. Particularly, we performed numerical simulations of the Ginzburg-Landau (GL) equations for a superconductor with an inhomogeneous profile of impurity concentration, a thin superconducting layer on top of another superconductor, and S-I-S multilayers. The superheating field was calculated taking into account the instability of the Meissner state at a finite wavelength along the surface depending on the value of the GL parameter. Simulations were done for the materials parameters of Nb and Nb₃Sn at different values of the GL parameter and the mean free paths. We show …
Numerical Simulations Of Radiation Reaction Using Lorentz-Abraham-Dirac Formalism, E. Rogers, B. Terzic, E. Breen, E. Johnson, G. Krafft
Numerical Simulations Of Radiation Reaction Using Lorentz-Abraham-Dirac Formalism, E. Rogers, B. Terzic, E. Breen, E. Johnson, G. Krafft
Physics Faculty Publications
An accelerating charged particle emits electromagnetic radiation. The motion of the particle is further damped via self-interaction with its own radiation. For relativistic particles, the subsequent motion is described via a correction to the Lorentz force, known as the Lorentz-Abraham-Dirac force. The aim of this research is to use the Lorentz-Abraham-Dirac force to computationally simulate the radiation damping that occurs during nonlinear inverse Compton scattering. We build on our previous work and the code which simulates single-emission inverse Compton scattering to incorporate the effect of multiple emissions, thereby modeling the radiation reaction.
Analytic And Numerical Calculation Of Collider Luminosity With Crab Dynamics, H. Huang, T. Satogata, Y. Zhang, Y. Roblin, F. Lin, S. Zhao
Analytic And Numerical Calculation Of Collider Luminosity With Crab Dynamics, H. Huang, T. Satogata, Y. Zhang, Y. Roblin, F. Lin, S. Zhao
Physics Faculty Publications
For an integral part of electron-ion collider (EIC) design, the crab crossing scheme provides a head-on collision for beams with a nonzero crossing angle. Recently we provided a framework for accurate numerical simulations of beam-beam effects with crabbing crossing dynamics. The framework was implemented in a simulation code package named “CASA BeamBeam”. We offer com-prehensive formulas for calculation of collider luminosity for various cases in the code package. The luminosity calculation module of CASA Beam-Beam now includes the hourglass effect, the beam-tilt effects and the beam offset effect. The benchmarking results show good agreement between the numerical calculation and analytic …
Combating Fake News: A Gravity Well Simulation To Model Echo Chamber Formation In Social Media, Jeremy E. Thompson
Combating Fake News: A Gravity Well Simulation To Model Echo Chamber Formation In Social Media, Jeremy E. Thompson
Dartmouth College Ph.D Dissertations
Fake news has become a serious concern as distributing misinformation has become easier and more impactful. A solution is critically required. One solution is to ban fake news, but that approach could create more problems than it solves, and would also be problematic from the beginning, as it must first be identified to be banned. We initially propose a method to automatically recognize suspected fake news, and to provide news consumers with more information as to its veracity. We suggest that fake news is comprised of two components: premises and misleading content. Fake news can be condensed down to a …