Physical Sciences and Mathematics Commons^™

Travel Time Theory For Traffic Conservation Laws With Applications, Sergio Contreras

UNLV Theses, Dissertations, Professional Papers, and Capstones

Travel time is an important concept in various intelligent transportation system (ITS) applications. The concept is used in a wide array of applications, such as system planning, system performance, and optimization. Reducing the time required to travel between different points on a network is an important goal. Benefits include reducing time wasted in traveling, and keeping travelers satisfied. Thus, studying and reducing travel time in ITS is beneficial in different applications.

The classic density-based Lighthill Whitman Richards (LWR) equation for modeling traffic flow is the starting point in this dissertation. A more recent travel time dynamics function built on top …

A Field-Programmable Metamaterial Using Memristor As A Stable Switcher, Taekuk Hong

Theses and Dissertations

Before the memristor was discovered, there were RLC circuits as representative passive devices. However, the fourth fundamental two-terminal circuit has been discovered by Dr. Leon Chua in 1971 and has been called a memristor. The memristor is a compound word of memory and resistor, and is an element whose resistive value is not constant and whose resistive value changes depending on the applied voltage and is recorded as a memory. It is mainly used in resistive switching and is the center of this research theme. A metamaterial is artificially created material that has never been found in nature. The theory …

Application Of Digital Twin Model In Grinding Of Bearing Rings, Hongbin Liu, Zhiqiang Shen, Yize Wang, Ming Qiu, Wenrong Lin

Journal of System Simulation

Abstract: The digital twin model can effectively promote the virtual-real interaction between the actual product and the product model. Aiming at the grinding force generated in the grinding process of spherical roller bearings, this paper constructs the bearing ring raceway grinding process by performing dynamics, contact algorithm modeling and rigid-flexible coupling treatment on the components of the grinding work area. The digital twin model completes the virtual mapping of the grinding work area of the bearing ring in the digital space. The model is used to analyze and test the process parameters such as the grinding wheel linear speed and …

Rapidly Changing Range Limits In A Warming World: Critical Data Limitations And Knowledge Gaps For Advancing Understanding Of Mangrove Range Dynamics In The Southeastern Usa, Rémi Bardou, Michael J. Osland, Steven Scyphers, Christine Shepard, Karen E. Aerni, Jahson B. Alemu I, Robert Crimian, Richard H. Day, Nicholas M. Enwright, Laura C. Feher, Sarah L. Gibbs, Kiera O'Donnell, Savannah H. Swinea, Kalaina Thorne, Sarit Truskey, Anna R. Armitage, Ronald Baker, Josh L. Breithaupt, Kyle C. Cavanaugh, Erik S. Yando, A. Randall Hughes, Et Al.

Biological Sciences Faculty Publications

Climate change is altering species’ range limits and transforming ecosystems. For example, warming temperatures are leading to the range expansion of tropical, cold-sensitive species at the expense of their cold-tolerant counterparts. In some temperate and subtropical coastal wetlands, warming winters are enabling mangrove forest encroachment into salt marsh, which is a major regime shift that has significant ecological and societal ramifications. Here, we synthesized existing data and expert knowledge to assess the distribution of mangroves near rapidly changing range limits in the southeastern USA. We used expert elicitation to identify data limitations and highlight knowledge gaps for advancing understanding of …

The Reversible Low-Temperature Instability Of Human Dj-1 Oxidative States, Tessa Andrews, Javier Seravallic, Robert Powers

Robert Powers Publications

DJ-1 is a homodimeric protein that is centrally involved in various human diseases including Parkinson disease (PD). DJ-1 protects against oxidative damage and mitochondrial dysfunction through a homeostatic control of reactive oxygen species (ROS). DJ-1 pathology results from a loss of function, where ROS readily oxidizes a highly conserved and functionally essential cysteine (C106). The over-oxidation of DJ-1 C106 leads to a dynamically destabilized and biologically inactivated protein. An analysis of the structural stability of DJ-1 as a function of oxidative state and temperature may provide further insights into the role the protein plays in PD progression. NMR spectroscopy, circular …

Impact Of Sample Conditions On Dna Phosphodiester Backbone Bi/Bii Conformational Equilibrium Dynamics, Autumn C. Pilarski

MSU Graduate Theses

DNA damage, such as single base lesions and mismatches, is highly prevalent within cells. If these DNA damage events are not repaired, they could lead to mutations and thus disease and cancer. Intricate repair mechanisms are in place to fix these damage events, one such being Base Excision Repair (BER) and associated enzyme: Thymine DNA Glycosylase (TDG). The first step of this repair process, recognition of the lesion by TDG, is not well understood. The following thesis presents results to better understand the fundamental biophysical question of how a DNA lesion within a mismatch context is recognized in a million …

Modeling The Spread Of Covid-19 In Spatio-Temporal Context, S.H. Sathish Indika, Norou Diawara, Hueiwang Anna Jeng, Bridget D. Giles, Dilini S.K. Gamage

Mathematics & Statistics Faculty Publications

This study aims to use data provided by the Virginia Department of Public Health to illustrate the changes in trends of the total cases in COVID-19 since they were first recorded in the state. Each of the 93 counties in the state has its COVID-19 dashboard to help inform decision makers and the public of spatial and temporal counts of total cases. Our analysis shows the differences in the relative spread between the counties and compares the evolution in time using Bayesian conditional autoregressive framework. The models are built under the Markov Chain Monte Carlo method and Moran spatial correlations. …

Investigating The Dynamics And Fragmentation Of Nitroaromatic Radical Cations Through Femtosecond Time-Resolved Mass Spectrometry And Computational Chemistry, Hugo Andres Lopez Pena

Theses and Dissertations

Chemists have sought to control molecular dissociation with lasers for decades. Effective control of unimolecular dissociation was only achieved with the development of high-intensity ultrashort pulsed lasers and coherent control techniques that operate on timescales faster than vibrational energy redistribution. In view of this, our lab has specialized in the study of polyatomic radical cations using femtosecond time-resolved mass spectrometry (FTRMS). The interest in radical cations stems from the fact that they are highly reactive species that contribute to many physical, chemical, and biological processes. For instance, radical cations participate in shock initiation of detonated energetic materials used as explosives …