Global Optimized Isothermal And Nonlinear Models Of Earth’S Standard Atmosphere, 2019 AAR Aerospace Consulting, LLC

#### Global Optimized Isothermal And Nonlinear Models Of Earth’S Standard Atmosphere, Nihad E. Daidzic, Ph.D.,

*Nihad E. Daidzic, Dr.-Ing., D.Sc., ATP, CFII, MEI*

Both, a global isothermal temperature model and a nonlinear quadratic temperature model of the ISA was developed and presented here. Constrained optimization techniques in conjunction with the least-square-root approximations were used to design best-fit isothermal models for ISA pressure and density changes up to 47 geopotential km for NLPAM, and 86 orthometric km for ISOAM respectively. The mass of the dry atmosphere and the relevant fractional-mass scale heights have been computed utilizing the very accurate eight-point Gauss-Legendre numerical quadrature for both ISOAM and NLPAM. Both, the ISOAM and the NLPAM represent viable alternatives to ISA in many practical applications and ...

Emergent Critical Properties In Liquid-Gas Transition And Single Dislocations In Solid He4, 2019 Graduate Center, City University of New York

#### Emergent Critical Properties In Liquid-Gas Transition And Single Dislocations In Solid He4, Max Yarmolinsky

*All Dissertations, Theses, and Capstone Projects*

My research focuses on the analytical and numerical study of seemingly completely different systems - the classical critical point of the liquid-gas transition and a quantum topological defect (dislocation) in solid Helium-4. The unifying theme, though, is *Emergence* - the appearance of unexpected qualities at large distance and time scales in these systems. Our results resolve the long standing controversy about the nature of the liquid-gas criticality by showing with high confidence that it is the same as that of Ising ferromagnet. In solid ^{4}He, a quantum *superclimbing* dislocation, which is expected to be violating space-time symmetry according to the elementary ...

Photo-Tunable Compression And Realization Of Colloidal Spin Ice In Skyrmion Arrays In Chiral Nematic Liquid Crystals, 2019 University of Colorado, Boulder

#### Photo-Tunable Compression And Realization Of Colloidal Spin Ice In Skyrmion Arrays In Chiral Nematic Liquid Crystals, Yuhan Wang

*Undergraduate Honors Theses*

Topological solitons are field configurations that are important to theorists in particle physics and cosmology, but recently have been studied in condensed matter systems with reconfigurable fields, like chiral magnets and liquid crystals. In these communities, there is a strong interest in studying and understanding the dynamic behavior of these solitons, many examples of which I will present in this thesis. This includes exploring the dynamic motion and patterning behavior of large number-densities of two-dimensional topological structures called skyrmions with external stimulation by light. With these techniques we can realize for the first time a colloidal spin ice system in ...

Practical Chaos: Using Dynamical Systems To Encrypt Audio And Visual Data, 2019 Scripps College

#### Practical Chaos: Using Dynamical Systems To Encrypt Audio And Visual Data, Julia Ruiter

*Scripps Senior Theses*

Although dynamical systems have a multitude of classical uses in physics and applied mathematics, new research in theoretical computer science shows that dynamical systems can also be used as a highly secure method of encrypting data. Properties of Lorenz and similar systems of equations yield chaotic outputs that are good at masking the underlying data both physically and mathematically. This paper aims to show how Lorenz systems may be used to encrypt text and image data, as well as provide a framework for how physical mechanisms may be built using these properties to transmit encrypted wave signals.

Hydrodynamics Of Smectic Liquid Crystal Films, 2019 University of Colorado, Boulder

#### Hydrodynamics Of Smectic Liquid Crystal Films, Eric Minor

*Undergraduate Honors Theses*

Smectic A and C liquid crystals are capable of forming incredibly thin films, discretized by the number of molecular layers. This property makes liquid crystal films ideal for studying 2D hydrodynamics, a field of great interest both due to its fundamental importance to physics and because of its applications to biological systems. The phospholipid bilayer which makes up cell membranes is itself an ideal 2D fluid as it consists of only two layers of phospholipids, however cell membranes are incredibly small and difficult to work worth. Liquid crystal films can be several millimeters across and stable for long periods of ...

Matlab Programs, 2018 Selected Works

#### Matlab Programs

*David D Nolte*

*Introduction to Modern Dynamics*

Application Of Graphical Models In Protein-Protein Interactions And Dynamics, 2018 University of Massachusetts Boston

#### Application Of Graphical Models In Protein-Protein Interactions And Dynamics, Amir Vajdi Hoojghan

*Graduate Doctoral Dissertations*

Every organism contains a few hundred to thousands of proteins. A protein is made of a sequence of molecular building blocks named amino acids. Amino acids will be referred to as residues. Every protein performs one or more functions in the cell. In order for a protein to do its job, it requires to bind properly to other partner proteins. Many genetic diseases such as cancer are caused by mutations (changes) of specific residues which cause disturbances in the functions of those proteins.

The problem of prediction of protein binding site is a crucial topic in computational biology. A protein ...

Fatigue Performance And Shear Demand Distributions Of Clustered Shear Connectors In Composite Bridge Girders, 2018 University of Arkansas, Fayetteville

#### Fatigue Performance And Shear Demand Distributions Of Clustered Shear Connectors In Composite Bridge Girders, Brian David Hillhouse

*Theses and Dissertations*

The current American Association of State Highway and Transportation Officials (AASHTO) Bridge Specifications assumes uniform shear flow demands at the steel-concrete interface of composite bridge girders. As stud pitch increases to beyond 24 in or as studs become clustered to account for pre-cast concrete decks, this assumed shear demand distribution may be unrepresentative. Understanding shear transfer and resulting demands on headed studs in composite beams are important for ensuring adequate composite design. This study investigates stud demands in composite bridge girders using large-scale fatigue testing and direct pressure measurements for stud force calculations. In this study, two large-scale composite beam ...

Reversible Motion In A Contact Line, 2018 California Polytechnic State University, San Luis Obispo

#### Reversible Motion In A Contact Line, Audrey Profeta, Esmeralda Orozco, Juan A. Ortiz Salazar, Dani Medina, Nathan C. Keim

*STAR (STEM Teacher and Researcher) Presentations*

When a body of liquid sits on a surface, an irregular border between the wet and dry regions of the surface exists, called the contact line. Driving this contact line back and forth repeatedly can change its shape.We use a syringe pump to cyclically infuse and withdraw a predetermined volume of water, and take photos of the contact line after each cycle. Comparing these images to each other determines if the contact line is returning to the same shape. We find that below a critical value of infused volume, after many cycles the contact line reaches a steady state ...

A Network Theoretical Approach To Real-World Problems: Application Of The K-Core Algorithm To Various Systems, 2018 The Graduate Center, City University of New York

#### A Network Theoretical Approach To Real-World Problems: Application Of The K-Core Algorithm To Various Systems, Kate Burleson-Lesser

*All Dissertations, Theses, and Capstone Projects*

The study of complex networks is, at its core, an exploration of the mechanisms that control the world in which we live at every scale, from particles no bigger than a grain of sand and amino acids that comprise proteins, to social networks, ecosystems, and even countries. Indeed, we find that, regardless of the physical size of the network's components, we may apply principles of complex network theory, thermodynamics, and statistical mechanics to not only better understand these specific networks, but to formulate theories which may be applied to problems on a more general level. This thesis explores several ...

Vibrating-Wire Rheometry, 2018 The University of Western Ontario

#### Vibrating-Wire Rheometry, Cameron C. Hopkins

*Electronic Thesis and Dissertation Repository*

This thesis consists of two projects on the behaviour of a novel vibrating-wire rheometer and a third project studying the gelation dynamics of aqueous solutions of Pluronic F127. In the first study, we use COMSOL to perform two-dimensional simulations of the oscillations of a wire in Newtonian and shear-thinning fluids. Our results show that the resonant behaviour of the wire agrees well with the theory of a wire vibrating in Newtonian fluids. In shear-thinning fluids, we find resonant behaviour similar to that in Newtonian fluids. In addition, we find that the shear-rate and viscosity in the fluid vary significantly in ...

Non-Hermitian Matter-Wave Mixing In Bose-Einstein Condensates: Dissipation-Induced Amplification, 2018 Bilkent University

#### Non-Hermitian Matter-Wave Mixing In Bose-Einstein Condensates: Dissipation-Induced Amplification, S. Wuster, Ramy El-Ganainy

*Ramy El-Ganainy*

We investigate the nonlinear scattering dynamics in interacting atomic Bose-Einstein condensates under non-Hermitian dissipative conditions. We show that, by carefully engineering a momentum-dependent atomic loss profile, one can achieve matter-wave amplification through four-wave mixing in a quasi-one-dimensional nearly-free-space setup—a process that is forbidden in the counterpart Hermitian systems due to energy mismatch. Additionally, we show that similar effects lead to rich nonlinear dynamics in higher dimensions. Finally, we propose a physical realization for selectively tailoring the momentum-dependent atomic dissipation. Our strategy is based on a two-step process: (i) exciting atoms to narrow Rydberg or metastable excited states, and (ii ...

Dynamics Of A Vertically Vibrated Doubly Tethered Granular Chain, 2018 Philippine Science High School Main Campus

#### Dynamics Of A Vertically Vibrated Doubly Tethered Granular Chain, Lorenzo P. Joquiño

*The International Student Science Fair 2018*

Polymer physics studies the structure and dynamics of polymers and polymeric systems. Results from polymer physics have been used in various fields such as biology, polymer processing, and electronics. Mechanical analogs like granular chain have been utilized in studying polymer dynamics as they are able to demonstrate coarsed-grained behavior of polymer motion while still being accurate about a polymer's properties at a larger length scale. In this study, vibrated granular chain of beads was used as an analog system to represent the polymer motion in a solution. The granular chain was confined to a circular container. Its both ends ...

Physical Lens On The Cell: Advanced Diffusion And The Fokker-Planck Picture, 2018 Oregon Health & Science University

#### Physical Lens On The Cell: Advanced Diffusion And The Fokker-Planck Picture, Daniel M. Zuckerman

*Scholar Archive*

On the one hand, the basics of diffusion seem easy to understand: random motion, a Gaussian distribution of steps, and linear (in time) mean-squared distance behavior. On the other hand, the diffusion equation is a partial differential equation ... and it only describes simple diffusion, whereas observed diffusion in cells is rarely simple and requires still more complicated math. Here you can deepen your understanding of the math and physics underlying diffusive behavior.

Numerical And Analytical Bounds On Threshold Error Rates For Hypergraph-Product Codes, 2018 University of Nebraska - Lincoln

#### Numerical And Analytical Bounds On Threshold Error Rates For Hypergraph-Product Codes, Alexey Kovalev, Sanjay Prabhakar, Ilya Dumer, Leonid P. Pryadko

*Faculty Publications, Department of Physics and Astronomy*

We study analytically and numerically decoding properties of finite-rate hypergraph-product quantum low density parity-check codes obtained from random (3,4)-regular Gallager codes, with a simple model of independent X and Z errors. Several nontrivial lower and upper bounds for the decodable region are constructed analytically by analyzing the properties of the homological difference, equal minus the logarithm of the maximum-likelihood decoding probability for a given syndrome. Numerical results include an upper bound for the decodable region from specific heat calculations in associated Ising models and a minimum-weight decoding threshold of approximately 7%.

Inference And Control In Regulatory Genomics, 2018 University of Maryland College Park

#### Inference And Control In Regulatory Genomics, Siddharth Sharma

*Biology and Medicine Through Mathematics Conference*

No abstract provided.

Lattice Scales From Gradient Flow And Chiral Analysis On The Milc Collaboration's Hisq Ensembles, 2018 Washington University in St. Louis

#### Lattice Scales From Gradient Flow And Chiral Analysis On The Milc Collaboration's Hisq Ensembles, Nathan Joseph Brown

*Arts & Sciences Electronic Theses and Dissertations*

The interactions of quarks and gluons form most of the visible matter around us. Yet, extracting precise predictions from the field theory describing them, Quantum Chromodynamics (QCD), is notoriously difficult. By simulating the QCD interaction on a Euclidean space time lattice, the field theory can be regularized non-perturbatively and familiar statistical techniques from classical statistical mechanics can be applied. Then, by systematically improving each component of the process, high precision results can be obtained. Some of the possible components to be improved include the discretization of the continuum action, the determination of the lattice scale(s), the generation of gauge ...

Vibrational Relaxation Theory For Systems Embedded In Microscopically Specified Reservoirs, 2018 University of New Mexico

#### Vibrational Relaxation Theory For Systems Embedded In Microscopically Specified Reservoirs, Anastasia Aemilia Ierides

*Physics & Astronomy ETDs*

This dissertation is a study of the theoretical framework of the practical as well as fundamental problem of the process of relaxation to equilibrium of quantum mechanical systems. The fundamental aspect is concerned with the simultaneous occurrence of decoherence and population equilibration. The practical aspect deals with experimental observations of vibrational relaxation of molecules embedded in liquids or solids. The systems include, but are not limited to, the nondegenerate dimer and harmonic oscillator, in one case weak and in the other strong, interaction with a thermal bath. The time dependence of the energy and the temperature dependence of the relaxation ...

Standard And Anomalous Wave Transport Inside Random Media, 2018 The Graduate Center, City University of New York

#### Standard And Anomalous Wave Transport Inside Random Media, Xujun Ma

*All Dissertations, Theses, and Capstone Projects*

This thesis is a study of wave transport inside random media using random matrix theory. Anderson localization plays a central role in wave transport in random media. As a consequence of destructive interference in multiple scattering, the wave function decays exponentially inside random systems. Anderson localization is a wave effect that applies to both classical waves and quantum waves. Random matrix theory has been successfully applied to study the statistical properties of transport and localization of waves. Particularly, the solution of the Dorokhov-Mello-Pereyra-Kumar (DMPK) equation gives the distribution of transmission.

For wave transport in standard one dimensional random systems in ...

Physical Applications Of The Geometric Minimum Action Method, 2018 The Graduate Center, City University of New York

#### Physical Applications Of The Geometric Minimum Action Method, George L. Poppe Jr.

*All Dissertations, Theses, and Capstone Projects*

This thesis extends the landscape of rare events problems solved on stochastic systems by means of the \textit{geometric minimum action method} (gMAM). These include partial differential equations (PDEs) such as the real Ginzburg-Landau equation (RGLE), the linear Schroedinger equation, along with various forms of the nonlinear Schroedinger equation (NLSE) including an application towards an ultra-short pulse mode-locked laser system (MLL).

Additionally we develop analytical tools that can be used alongside numerics to validate those solutions. This includes the use of instanton methods in deriving state transitions for the linear Schroedinger equation and the cubic diffusive NLSE.

These analytical solutions ...