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Quantifying Effects Of Using Thermally Thin Fuel Approximations On Modelling Fire Propagation In Woody Fuels, David Blasen, Jesse Johnson, William Jolly, Russell Parsons

Graduate Student Theses, Dissertations, & Professional Papers

In this paper, we quantify the effects of the thermally thin fuel approximations commonly made in numerical models that eliminate temperature gradients within a heated object. This assumption is known to affect the modeled ignition and burn behavior, but there is little research on its impact, particularly in larger fuels or in numerical models including moisture and chemical decomposition of fuels.

We begin by comparing modeled to observed ignition times and burn rates. To constrain variability in the material properties of wood and focus on variability caused by fuels assumed to be thermally thin, we conduct experiments using thermogravimetric analysis …

Developing Physics Problem-Solving Skill Test For Grade X Students Of Senior High School, Amipa Tri Yanti Nadapdap, Edi Istiyono

REID (Research and Evaluation in Education)

This research aimed to develop a physics problem-solving skill (PSS) test for grade X students of senior high school which met test instrument characteristics and feasibility. The development stages included: (a) test designing, (b) test trial, and (c) test revision and preparation. The designing stage included: (1) needs analysis, (2) mapping, (3) drawing conclusion, (4) determining test purpose, (5) determining competencies, (6) determining materials, (7) preparing answers, (8) writing items, (9) validating content, (10) improving and preparing the test, and (11) preparing the scoring guide with PCM. The trial stage consisted of: (1) determining trial subjects, (2) performing trial, and …

Underwater Acoustic Signal Analysis Toolkit, Kirk Bienvenu Jr

LSU New Orleans Theses and Dissertations

This project started early in the summer of 2016 when it became evident there was a need for an effective and efficient signal analysis toolkit for the Littoral Acoustic Demonstration Center Gulf Ecological Monitoring and Modeling (LADC-GEMM) Research Consortium. LADC-GEMM collected underwater acoustic data in the northern Gulf of Mexico during the summer of 2015 using Environmental Acoustic Recording Systems (EARS) buoys. Much of the visualization of data was handled through short scripts and executed through terminal commands, each time requiring the data to be loaded into memory and parameters to be fed through arguments. The vision was to develop …

Muon-Neutrino Electron Elastic Scattering And A Search For The Muon-Neutrino Magnetic Moment In The Nova Near Detector, Biao Wang

Physics Theses and Dissertations

We use the NOvA near detector and the NuMI beam at Fermilab to study the neutrino-electron elastic scattering and the muon neutrino magnetic process beyond the Standard Model physics. The particle identifications of neutrino on electron elastic scattering are trained by using the multi-layer neural networks. This thesis provides a general discussion of this technique and shows a good agreement between data and MC for the neutrino-electron elastic weak scattering. By using 3.62e20 POT dataset in the NOvA near detector, we find 1.58e-9 Bohr magneton as the 90% C.L. upper limit. We also find a sensitivity of 8e-10 Bohr magneton …

The Influence Of Previous Subject Experience On Interactions During Peer Instruction In An Introductory Physics Course: A Mixed Methods Analysis, Judy A. Vondruska

College of Education and Human Sciences: Dissertations, Theses, and Student Research

Over the past decade, peer instruction and the introduction of student response systems has provided a means of improving student engagement and achievement in large-lecture settings. While the nature of the student discourse occurring during peer instruction is less understood, existing studies have shown student ideas about the subject, extraneous cues, and confidence level appear to matter in the student-student discourse. Using a mixed methods research design, this study examined the influence of previous subject experience on peer instruction in an introductory, one-semester Survey of Physics course. Quantitative results indicated students in discussion pairs where both had previous subject experience …

Measurement Of Vector Boson Scattering And Constraints On Anomalous Quartic Couplings From Events √With Four Leptons And Two Jets In Proton–Proton Collisions At √ S = 13tev, The Cms Collaboration, M. M. Baarmand, Vallary Bhopatkar, S. Colafranceschi, M. Hohlmann, D. Noonan, T. Roy, F. Yumiceva

Aerospace, Physics, and Space Science Faculty Publications

A measurement of vector boson scattering and constraints on anomalous quartic gauge couplings from events with two Z bosons and two jets are presented. The analysis is based on a data sample of proton–proton collisions at 𝑠=13TeV collected with the CMS detector and corresponding to an integrated luminosity of 35.9fb−1. The search is performed in the fully leptonic final state ZZ→ℓℓℓ′ℓ′, where ℓ,ℓ′=e or μ. The electroweak production of two Z bosons in association with two jets is measured with an observed (expected) significance of 2.7 (1.6) standard deviations. A fiducial cross section for the electroweak production is measured …

Phys 211: Mechanics, Gravitation, And Waves, Ilya Kravchenko

Department of Physics and Astronomy: Syllabi

Syllabus for PHYS 211: Mechanics, Gravitation, and Waves syllabus for Fall 2017 semester.

College Of Science And Mathematics Newsletter, Fall 2017, College Of Science And Mathematics, Wright State University

College of Science and Mathematics Newsletters

This 6 page newsletter discusses various happenings within the College of Science and Mathematics. It begins with a letter from the dean, and continues on with news, events, alumni news, and other community news.

Phys 201: Modern Topics In Physics And Astronomy, Ken Bloom

Department of Physics and Astronomy: Syllabi

Syllabus for PHYS 201: Modern Topics in Physics and Astronomy syllabus for Fall 2017.

Nuclear Magnetic Resonance Studies Of Electrode And Electrolyte Materials For Li-Ion Batteries, Lisa Cirrincione

Dissertations, Theses, and Capstone Projects

In this thesis, Nuclear Magnetic Resonance (NMR) spectroscopic techniques are used to study lithium electrode and electrolyte materials for advanced rechargeable lithium ion batteries. Three projects are described in this thesis. The first involves ²³Na and ³⁷Al static and magic angle spinning NMR studies of NaAlH₄/C anode materials for advanced rechargeable batteries. The second project is a study of paramagnetic lithium transition-metal phosphate cathode materials for Li-ion batteries, where ⁷Li, and ³¹P single crystal NMR was used in order to obtain detailed information on the local electronic and magnetic environments. The third project investigates …

Foundations, 3, David Peak

Foundations

Our goal is to try to reconcile classical EM with the existence of photons. The electric and magnetic fields associated with EM radiation, propagating in the x -direction, obey the Maxwell wave equation: ∂²E/∂t² = c²(∂²E/∂x²).

Many-Particle Systems, 3, David Peak

Many Particles

Bare essentials of statistical mechanics

Atoms are examples of many-particle systems, but atoms are extraordinarily simpler than macroscopic systems consisting of 10²⁰-10³⁰ atoms. Despite their great size, many properties of macroscopic systems depend intimately on the microscopic behavior of their microscopic constituents. The proper quantum mechanical description of an N -particle system is a wavefunction that depends on 3N coordinates (3 ways of moving, in general, for every particle) and 4N quantum numbers (3 motional quantum numbers and 1 spin quantum number for every particle). (If the “particles” are molecules there might be additional quantum …

Many-Particle Systems, 1, David Peak

Many Particles

Wavefunctions for more than one particle: Different kinds of particles

Introductory examples of quantum mechanical wavefunction calculations involve a single particle moving about in a “magic” potential energy—e.g., a particle trapped inside a square well or an electron in a hydrogen atom. But, potential energy arises from interaction, so these situations must inevitably include more than one particle. Even the simplest atom—hydrogen— consists of two particles: the electron and the proton. So, how should the Schrödinger Equation be generalized to account for multiple particles?

Many-Particle Systems, 8, David Peak

Many Particles

The classical picture of how electrons migrate through a resistor driven by an applied potential difference draws an analogy with a kind of pinball machine. In a pinball machine, gravity accelerates the pinball down the table, but the ball’s progress is impeded by collisions with bumpers, as depicted to the right. (θ is the angle the table makes with the horizontal direction.) When averaged over many collisions the ball’s average equation of motion is ma = mg sinθ − mv/τ , where a and v are directed down the table, and τ is the average time between collisions. If the …

Problem Set #4, David Peak

Problems

Some 1D infinite well stuff

Problem Set #12, David Peak

Problems

Solid stuff

Problem Set #7, David Peak

Problems

Atom stuff

Many-Particle Systems, 5, David Peak

Many Particles

Photons as T → 0 K

Photons are massless bosons. Because they are massless, any number of them can be added or subtracted without changing the photon system energy. (For example, a 1 eV photon can be exchanged for one hundred 0.01 eV photons, without changing system energy.) As a result, the chemical potential for photons is zero.

Physics 2710: Introductory Modern Physics, David Peak

Syllabus

No abstract provided.

Problem Set #8, David Peak

Problems

A bit of stat mech

Problems 1-3 refer to: N identical, noninteracting, and distinguishable spin-1/2 particles (i.e., their separation is much greater than their de Broglie wavelength) are placed in an external magnetic field. Assume the ground state energy of one such particle is 0 and the excited state energy is ε , and the system is in thermal equilibrium at temperature T.

Problem Set #10, David Peak

Problems

Blackbody

Problem Set #2, David Peak

Problems

A little energy and momentum practice (and units)

Problems 1-2 deal with “rest” energy and relativity.

Foundations, 1, David Peak

Foundations

Quantum mechanics is money

Text message and take a picture with your smart phone; watch a movie on your Blu-ray player; get the bar code on your bag of chips scanned; obtain an MRI image of your aching shoulder; take a ride on a maglev train. None of these—and countless other—things would be possible without quantum mechanics! Leon Lederman, Nobel Prize winning physicist, is widely quoted as saying that 1/3 of the world’s economy is due to quantum mechanics. Lederman’s estimate is actually probably too low, but what surely is the case is that computers, lasers, and superconducting magnets (to …

Schrödinger, 2, David Peak

Schrodinger

The finite square well

The infinite square well potential energy rigorously restricts the associated wavefunction to an exact region of space: it is infinitely “hard.” Potential energies encountered in more realistic physical scenarios are “softer” in that they permit wavefunctions to spread throughout less well-defined regions. An important toy example of the latter is the finite square well. In this problem, the potential energy function is U(x) = 0, if 0 < x < L, and U₀ otherwise.

Schrödinger, 4, David Peak

Schrodinger

The sanitized hydrogen atom: separating the variables

Separation of variables in the Schrödinger Equation for the hydrogen problem requires expressing Ψ as a product, Ψ(r,θ,φ,t) = R(r)Θ(θ )Φ(φ)T(t) , substituting into the partial differential equation [(5) in Sc3], and then dividing by Ψ. As in the square well problems, the separation constant for the t part of the separation is the particle’s eigen-energy, E.

Many-Particle Systems, 2, David Peak

Many Particles

Multi-electron atoms

The rich diversity of chemical processes and structures is directly related to the diversity of electronic states of multi-electron atoms that, in turn, is dictated by the Pauli Exclusion Principle. To see how the Pauli Exclusion Principle produces atomic diversity, it is useful to begin simply, in particular, by considering the most elementary multi-electron “atom”: the hydrogen anion, H^–.

Many-Particle Systems, 4, David Peak

Many Particles

Absolute temperature

When a system is in statistical equilibrium it can usefully be characterized by a few macroscopic variables. Temperature is one of the most important of these. The absolute temperature scale (measured in kelvins, K) has the following properties. (1) T = 0 K is the temperature of a macroscopic system found permanently in its ground state. Such a system has no excitations; it has its lowest possible energy and is completely isolated from the rest of the universe.

Many-Particle Systems, 7, David Peak

Many Particles

Electronic energy bands in crystalline solids: The finite well model

Previously, we have considered the “conduction electrons” in a metal as if they were an ideal gas in a 3D infinite well. What allows us to do that? A crystalline solid consists of a periodic array of atoms, packed so close to one another that “flow” (long range relative motion of groups of atoms) is essentially impossible. It is useful to think of a solid as a giant (rigid) molecule. The periodic structure of the atoms has profound consequences for the behavior of the solid’s electrons. While, in detail, the …

Many-Particle Systems, 9, David Peak

Many Particles

Superconductivity phenomenology

Superconductors are materials that exhibit zero (or close to zero) resistance to electrical currents as well as perfect diamagnetism (the Meissner Effect). When a current is started in a superconducting loop, it persists for a very long time without an applied potential difference. The resistivity of a superconductor is measured to be less than 4x10^–25 Ω-m (for comparison, the resistivity of an ordinary good conductor is about 10^–8 Ω-m), and the associated decay time for the current is estimated to be greater than 100,000 years (as opposed to about 1 µs for an ordinary good …

Many-Particle Systems, 11, David Peak

Many Particles

Quantum information

In Mn10 we discussed the rudiments of “classical computation.” Classical, conventional computation involves combinations of transistors that convert low- and high-voltage inputs into different low- and high-voltage outputs. These voltages are interpreted as the binary digits 0 and 1, i.e., as bits. How bits are changed into other bits leads to such things as text preparation and storage, numerical calculations and symbolic manipulations, image and sound generation, game playing, intercontinental communication—in short, the modern world of information.