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We present Karl G. Jansky Very Large Array 1.3, 3.6, and 6 cm continuum maps of compact radio sources in the Orion Nebular Cluster (ONC). We mosaicked 34 arcmin(2) at 1.3 cm, 70 arcmin(2) at 3.6 cm and 109 arcmin(2) at 6 cm, containing 778 near-infrared detected young stellar objects and 190 Hubble Space Telescope-identified proplyds (with significant overlap between those characterizations). We detected radio emission from 175 compact radio sources in the ONC, including 26 sources that were detected for the first time at these wavelengths. For each detected source, we fitted a simple free-free and dust emission model to characterize the radio emission. We extrapolate the free-free emission spectrum model for each source to ALMA bands to illustrate how these measurements could be used to correctly measure protoplanetary disk dust masses from submillimeter flux measurements. Finally, we compare the fluxes measured in this survey with previously measured fluxes for our targets, as well as four separate epochs of 1.3 cm data, to search for and quantify the variability of our sources.

We present multi-wavelength studies of the radio galaxy 3C 120 and the blazar CTA 102 during unprecedented gamma-ray flares for both sources. In both studies the analysis of gamma-ray data has been compared with a series of 43 GHz VLBA images from the VLBA-BU-BLAZAR program, providing the necessary spatial resolution to probe the parsec scale jet evolution during the high energy events. To extend the radio dataset for 3C 120 we also used 15 GHz VLBA data from the MOJAVE sample. These two objects which represent very different classes of AGN, have similar properties during the gamma-ray events. The gamma-ray flares are associated with the passage of a new superluminal component through the mm VLBI core, but not all ejections of new components lead to gamma-ray events. In both sources gamma-ray events occurred only when the new components are moving in a direction closer to our line of sight. We locate the g-ray dissipation zone a short distance from the radio core but outside of the broad line region, suggesting synchrotron self-Compton scattering as the probable mechanism for the gamma-ray production.

Core-collapse supernovae (CCSN) are among the most energetic explosions in the universe, liberating ~1053 erg of gravitational binding energy of the stellar core. Most of this energy ( ~99%) is emitted in neutrinos and only 1% is released as electromagnetic radiation in the visible spectrum. Energy radiated in the form of gravitational waves (GWs) is about five orders smaller. Nevertheless, this energy corresponds to a very strong GW signal and, because of this CCSN are considered as one of the prime sources of gravitational waves for interferometric detectors. Gravitational waves can give us access to the electromagnetically hidden compact inner core of supernovae. They will provide valuable information about the angular momentum distribution and the baryonic equation of state, both of which are uncertain. Furthermore, they might even help to constrain theoretically predicted SN mechanisms. Detection of GW signals and analysis of the observations will require realistic signal predi ctions from the non-parameterized relativistic numerical simulations of CCSN. This dissertation presents the gravitational wave signature of core-collapse v supernovae. Previous studies have considered either parametric models or nonexploding models of CCSN. This work presents complete waveforms, through the explosion phase, based on first-principles models for the first time. We performed 2D simulations of CCSN using the CHIMERA code for 12, 15, and 25M non-rotating progenitors. CHIMERA incorporates most of the criteria for realistic core-collapse modeling, such as multi-frequency neutrino transport coupled with relativistic hydrodynamics, eective GR potential, nuclear reaction network, and an industry-standard equation of state. / Based on the results of our simulations, I produced the most realistic gravitational waveforms including all postbounce phases of core-collapse supernovae: the prompt convection, the stationary accretion shock instability, and the corresponding explosion. Additionally, the tracer particles applied in the analysis of the GW signal reveal the origin of low-frequency component in the prompt part of gravitational waveform. Analysis of detectability of the GW signature from a Galactic event shows that the signal is within the band-pass of current and future GW observatories such as AdvLIGO, advanced Virgo, and LCGT. / by Konstantin Yakunin. / Thesis (Ph.D.)--Florida Atlantic University, 2011. / Includes bibliography. / Electronic reproduction. Boca Raton, Fla., 200?. Mode of access: World Wide Web.

In a recent investigation conducted by the United States Air Force, the mechanical failure of the aileron lever, manufactured from 2014-T6 aluminum, caused the fatal mishap of a T-38 trainer aircraft. In general the locations of cracks are unknown and must be determined by simulation. In this study we propose to use a continuum damage modeling approach to determine the degradation and damage in a material as the number of cycles of loading increases. This approach successfully predicts the location of crack initiation, propagation path, and propagation rate. A stress-based model in conjunction with the successive initiation technique is utilized. Successive initiation is based on the idea that damage will accrue in a material. Each element inside a new material will have a value of 0 damage assigned to it. Over time, the damage that occurs due to stresses on individual elements will add until the damage reaches a value of 1. At that point, failure of the element will occur. A code was developed in ANSYS that can draw, mesh, and apply appropriate forces on the aileron lever for successive runs. By using the S-N curve for the 2014-T6 aluminum material, the material damage constants are found. This stress-based damage model is then used to determine the state of damage in each element. Each time the elements are stressed, a particular amount of damage will occur. When an element reaches a specific amount of damage, ANSYS will "kill" the element, resulting in the element no longer adding to the stiffness matrix of the material. Variability is a common occurrence in all aspects of engineering such as manufacturing, testing, and loading. A Monte Carlo simulation is used to determine the sensitivity of the results to variability of input parameters by ± 15%. Input parameters include loads, material properties and damage model constants. The Monte Carlo simulation indicates the only significant input in the initiation life of the material is the exponential value in the stress-based fatigue life equation. Material properties and load variations in the ± range will not significantly change the life prediction results.

This thesis explores the vibrational behavior of the main components of sound production in the violin using a continuum mechanics approach. The author provides a mathematical description of the regions in the vibrating continuum, and begins to develop a system of equations governing their behavior, focusing on the air in the resonant chamber. Later chapters, contain discussion of issues involved in solving the system of equations, and examples involving both formal and numerical methods. The existence of a unique formal solution would allow mathematicians to make predictive models for sound waves of instruments based on physical characteristics such as size, shape, density and elasticity. / Graduation date: 2004

Biomolecular structure and interactions in aqueous environment are determined by a complicated interplay between physical and chemical forces including solvation, electrostatics, van der Waals forces, the hydrophobic effect and covalent bonding. Among them, electrostatics has been of particular interest due to its long-range nature and the tradeoff between desolvation and interaction effects [1]. In addition, electrostatic interactions play a significant role within a biomolecule as well as between biomolecules, making the balance between the two vital to the understanding of macromolecular systems. As a result, much effort has been devoted to accurate modeling and simulation of biomolecule electrostatics. One important application of this work is to compute the structure of electrostatic interactions for a biomolecule in an electrolyte solution, as well as the potential that the molecule generates in space. There are two valuable uses for these simulations. First, it provides a full picture of the electrostatic energetics of a biomolecular system, improving our understanding of how electrostatics contributes to stability, specificity, function, and molecular interaction [2]. Second, these simulations serve as a tool for molecular design, since electrostatic complementarity is an important feature of interacting molecules. Through examination of the electrostatics and potential field generated by a protein molecule, for example, it may be possible to suggest improvements to other proteins or drug molecules that interact with it, or perhaps even design new interacting molecules de novo [3]. There are two approaches in simulating a protein macromolecule in an aqueous solution with nonzero ionic strength. Discrete/atomistic approaches based on Monte-Carlo or molecular dynamics simulations treat the macromolecule and solvent explicitly at the atomic level. Therefore, an enormous number of solvent molecules are required to provide reasonable accuracy, especially when electric fields far away from macroscopic surface are of interest, leading to computational infeasibility. In this work, we adopt instead an approach based on a continuum description of the macromolecule and solvent. Although the continuum model of biomolecule electrostatics is widely used, the numerical techniques used to evaluate the model do not exploit fast solver approaches developed for analyzing integrated circuit interconnect. I will describe the formulation used for analyzing biomolecule electrostatics, and then derive an integral formulation of the problem that can be rapidly solved with precorrected-FFT method [4]. / Singapore-MIT Alliance (SMA)

Thesis (Ph. D.)--University of Rhode Island, 2005. / Typescript. Includes bibliographical references (leaves 126-134).

What makes identity readable? To answer this question, I examine the constructions of queer, non-German women in three contemporary transnational German films, Aimée und Jaguar, Fremde Haut and Auf der anderen Seite. To become readable, and thus to survive within the socio-political realm of German culture, these protagonists must construct and perform interconnected dimensions of identity— sex, gender, sexuality, ethnicity, language, clothing, and name—that can be located along a hegemonic-defined continuum. But when the characters cannot be read within this framework, they trouble dominant readings and understandings of their positions in this system and disrupt normative conceptions of identity. These threats to the system, however, do not lead to a renegotiation of the protagonists’ identities. Rather, hegemonic German society reacts to the unreadability of these queer figures by violently rejecting them through deportation and/or death.