System Optimization And Iterative Image Reconstruction In Photoacoustic Computed Tomography For Breast Imaging,
2017
Washington University in St. Louis
System Optimization And Iterative Image Reconstruction In Photoacoustic Computed Tomography For Breast Imaging, Yang Lou
McKelvey School of Engineering Graduate Student Theses & Dissertations
Photoacoustic computed tomography(PACT), also known as optoacoustic tomography (OAT), is an emerging imaging technique that has developed rapidly in recent years. The combination of the high optical contrast and the high acoustic resolution of this hybrid imaging technique makes it a promising candidate for human breast imaging, where conventional imaging techniques including X-ray mammography, B-mode ultrasound, and MRI suffer from low contrast, low specificity for certain breast types, and additional risks related to ionizing radiation. Though significant works have been done to push the frontier of PACT breast imaging, it is still challenging to successfully build a PACT breast imaging …
Flow Anisotropy Due To Thread-Like Nanoparticle Agglomerations In Dilute Ferrofluids,
2017
Montclair State University
Flow Anisotropy Due To Thread-Like Nanoparticle Agglomerations In Dilute Ferrofluids, Alexander Cali, Wah-Keat Lee, A. David Trubatch, Philip Yecko
Department of Applied Mathematics and Statistics Faculty Scholarship and Creative Works
Improved knowledge of the magnetic field dependent flow properties of nanoparticle-based magnetic fluids is critical to the design of biomedical applications, including drug delivery and cell sorting. To probe the rheology of ferrofluid on a sub-millimeter scale, we examine the paths of 550 μm diameter glass spheres falling due to gravity in dilute ferrofluid, imposing a uniform magnetic field at an angle with respect to the vertical. Visualization of the spheres’ trajectories is achieved using high resolution X-ray phase-contrast imaging, allowing measurement of a terminal velocity while simultaneously revealing the formation of an array of long thread-like accumulations of magnetic …
Speckle Effects In Target-In-The-Loop Laser Beam Projection Systems,
2017
University of Dayton
Speckle Effects In Target-In-The-Loop Laser Beam Projection Systems, Mikhail Vorontsov
Electro-Optics and Photonics Faculty Publications
In target-in-the-loop laser beam projection scenarios typical of remote sensing, directed energy, and adaptive optics applications, a transmitted laser beam propagates through an optically inhomogeneous medium toward a target, scatters off the target’s rough surface, and returns back to the transceiver plane. Coherent beam scattering off the randomly rough surface results in strong speckle modulation in the transceiver plane. This speckle modulation has been a long-standing challenge that limits performance of remote sensing, active imaging, and adaptive optics techniques. Using physics-based models of laser beam scattering off a randomly rough surface, we show that received speckle-field spatial and temporal characteristics …
Energy From Active Galactic Nuclei And The Effects On Host Spiral Galaxies,
2017
University of Arkansas, Fayetteville
Energy From Active Galactic Nuclei And The Effects On Host Spiral Galaxies, Amanda Schilling
Graduate Theses and Dissertations
I have investigated the energy output of active galactic nuclei (AGN) in order to understand how these objects evolve and the impact they may have on host galaxies. First, I looked at a sample of 96 AGN at redshifts $z \sim 2, 3,$ and $4$ which have imaging and thus luminosity measurements in the $griz$ and $JHK$ observed wavebands. For these galaxies, I have co-epochal data across those bands which accounted for variability in AGN luminosity. I used the luminosity measurements in the five bands to construct spectral energy distributions (SED) in the emitted optical-UV bands for each AGN. I …
Qualitative Results On Mixed Problem Of Micropolar Bodies With Microtemperatures,
2017
Transilvania University of Brasov
Qualitative Results On Mixed Problem Of Micropolar Bodies With Microtemperatures, Marin Marin, Lavinia Codarcea, Adina Chirila
Applications and Applied Mathematics: An International Journal (AAM)
The aim of our study is to transform the mixed initial boundary value problem considered in the context of micropolar thermoelastic bodies whose micro-particles possess microtemperatures in a temporal evolutionary equation on a Hilbert space. Then, with the help of some results from the theory of semigroups, the existence and the uniqueness of the solution for this equation is proved. Finally, we approach the continuous dependence of the solution upon initial data and loads, also with the help of the semigroup.
Fractional Order Thermoelastic Deflection In A Thin Circular Plate,
2017
Dr. Ambedkar College
Fractional Order Thermoelastic Deflection In A Thin Circular Plate, J. J. Tripathi, S. D. Warbhe, K. C. Deshmukh, J. Verma
Applications and Applied Mathematics: An International Journal (AAM)
In this work, a quasi-static uncoupled theory of thermoelasticity based on time fractional heat conduction equation is used to model a thin circular plate, whose lower surface is maintained at zero temperature whereas the upper surface is insulated. The edge of the circular plate is fixed and clamped. Integral transform technique is used to derive the analytical solutions in the physi-cal domain. The numerical results for temperature distributions and thermal deflection are com-puted and represented graphically for Copper material.
Thermoelastic Analysis Of A Nonhomogeneous Hollow Cylinder With Internal Heat Generation,
2017
RTM Nagpur University
Thermoelastic Analysis Of A Nonhomogeneous Hollow Cylinder With Internal Heat Generation, V. R. Manthena, N. K. Lamba, G. D. Kedar
Applications and Applied Mathematics: An International Journal (AAM)
In the present paper, we have determined the heat conduction and thermal stresses of a hollow cylinder with inhomogeneous material properties and internal heat generation. All the material properties except Poisson’s ratio and density are assumed to be given by a simple power law in axial direction. We have obtained the solution of the two dimensional heat conduction equation in the transient state in terms of Bessel’s and trigonometric functions. The influence of inhomogeneity on the thermal and mechanical behavior is examined. Numerical computations are carried out for both homogeneous and nonhomogeneous cylinders and are represented graphically.
Interactions Of Thermoelastic Beam In Modified Couple Stress Theory,
2017
Kurukshetra University
Interactions Of Thermoelastic Beam In Modified Couple Stress Theory, Rajneesh Kumar, Shaloo Devi
Applications and Applied Mathematics: An International Journal (AAM)
This paper is concerned with the study of thermoelastic beam in modified couple stress theory. The governing equations of motion for modified couple stress theory and heat conduction equation for non-Fourier (non-classical process) are investigated to model the vibrations in a homogeneous isotropic thin beam in a closed form by employing the Euler Bernoulli beam theory. The generalized theories of thermoelasticity with one and two relaxation times are used to model the problem. Both ends of the beam are simply supported. The Laplace transform technique applied to solve the system of equations which are written in dimensionless form. A general …
Applications Of Planar Newtonian Four-Body Problem To The Central Configurations,
2017
S. M. College, T. M. Bhagalpu University
Applications Of Planar Newtonian Four-Body Problem To The Central Configurations, M. R. Hassan, M. S. Ullah, Md. Aminul Hassan, Umakant Prasad
Applications and Applied Mathematics: An International Journal (AAM)
The present study deals with the applications of the planar Newtonian four-body problem to
the different central configurations. The basic concept of central configuration is that the
vector force must be in the direction of the position vector so that the origin may be taken at
the centre of mass of the four bodies and the force towards the position vector multiplied by
corresponding inverse mass is directly proportional to the position vector relative to the
centre of mass. For applying the Newtonian four body problem to the central configuration,
the equations of motion of four bodies have been established …
Weak-Value Amplification And Optimal Parameter Estimation In The Presence Of Correlated Noise,
2017
University of Toronto
Weak-Value Amplification And Optimal Parameter Estimation In The Presence Of Correlated Noise, Josiah Sinclair, Matin Hallaji, Aephraim M. Steinberg, Jeff Tollaksen, Andrew N. Jordan
Mathematics, Physics, and Computer Science Faculty Articles and Research
We analytically and numerically investigate the performance of weak-value amplification (WVA) and related parameter estimation methods in the presence of temporally correlated noise. WVA is a special instance of a general measurement strategy that involves sorting data into separate subsets based on the outcome of a second “partitioning” measurement. Using a simplified correlated noise model that can be analyzed exactly together with optimal statistical estimators, we compare WVA to a conventional measurement method. We find that WVA indeed yields a much lower variance of the parameter of interest than the conventional technique does, optimized in the absence of any partitioning …
Analysis Of The Joint Impact Of Atmospheric Turbulence And Refractivity On Laser Beam Propagation,
2017
Optonicus
Analysis Of The Joint Impact Of Atmospheric Turbulence And Refractivity On Laser Beam Propagation, Victor A. Kulikov, Mikhail Vorontsov
Electro-Optics and Photonics Faculty Publications
A laser beam propagation model that accounts for the joint effect of atmospheric turbulence and refractivity is introduced and evaluated through numerical simulations. In the numerical analysis of laser beam propagation, refractive index inhomogeneities along the atmospheric propagation path were represented by a combination of the turbulence-induced random fluctuations described in the framework of classical Kolmogorov turbulence theory and large-scale refractive index variations caused by the presence of an inverse temperature layer. The results demonstrate that an inverse temperature layer located in the vicinity of a laser beam’s propagation path may strongly impact the laser beam statistical characteristics including the …
Proposed Method For Measuring The Let Of Radiotherapeutic Particle Beams,
2017
University of New Mexico - Main Campus
Proposed Method For Measuring The Let Of Radiotherapeutic Particle Beams, Stephen D. Bello
Physics & Astronomy ETDs
The Bragg peak geometry of the depth dose distributions for hadrons allows for precise and effective dose delivery to tumors while sparing neighboring healthy tissue. Further, compared against other forms of radiotherapeutic treatments, such as electron beam therapy (EBT) or photons (x and \(\gamma\)-rays), hadrons create denser ionization events along the particle track, which induces irreparable damage to DNA, and thus are more effective at inactivating cancerous cells. The measurement of radiation's ability to inactivate cellular reproduction is the relative biological effectiveness (RBE). A quality related to the RBE that is a measurable physical property is the linear energy transfer …
Geothermal Flux And Phreatic Speleogenesis In Gypsum, Halite, And Quartzite Rocks,
2017
University of Torino
Geothermal Flux And Phreatic Speleogenesis In Gypsum, Halite, And Quartzite Rocks, Giovanni Badino
International Journal of Speleology
The first layers of rock underground are in thermal contact with the external atmosphere mainly through infiltrating meteoric water. This relatively cool zone absorbs rising geothermal energy, which heats the water. If the aquifer consists of gypsum, halite or quartzite, the water at those depths is usually salt-saturated, so the increase in temperature renders the water aggressive again. This in turn leads to rock dissolution and formation of phreatic conduits. This way, the geothermal flow creates caves that do not necessarily reach the surface. This paper analyzes the speed of the excavation, which, in different types of rocks, depends only …
Superconductivity At Т≈200 K In Bismuth Cuprates Synthesized Using Solar Energy,
2017
Tbilisi State University
Superconductivity At Т≈200 K In Bismuth Cuprates Synthesized Using Solar Energy, J. Chigvinadze, Juana Acrivos, S. Ashimov, D. Gulamova, G. Donadze
Faculty Publications, Chemistry
When investigating low-frequency (0.1 Hz) oscillations of multiphase high-temperature cuprate superconductors (HTCS) Bi1,7Pb0,3Sr2Ca(n-1)CunOy (n=2-30), a wide attenuation peak (ΔT~100 К) with a maximum at Т≈200 К was detected. This peak was particularly pronounced in field cooling (FC) experiments, i.e. after abrupt cooling of the sample in the external magnetic field at the temperature Т<Тс with subsequent slow warming up to room temperature with invariance of the applied field. The attenuation peak height depended on the preliminaryorientation (before cooling) of the samples θ in the measured permanent magnetic field Н. On the one hand, it is well known that, after the FC procedure and subsequent slow warming up, at the temperatures close to the critical temperature Тс, the attenuation peak associated with “melting” of the Abrikosov frozen vortex structure and its disappearance at Т >Тс is detected in monophase samples. At the same time, in most multiphase bismuth HTCS samples, synthesized using solar energy and superfast quenching of the melt, the attenuation peak with the maximum at Т≈200 К was observed.Depending on the conditions of synthesis, the attenuation peak could …
Calibration Of Temperature Sensors In Preparation For The 2017 Total Solar Eclipse,
2017
St. Catherine University
Calibration Of Temperature Sensors In Preparation For The 2017 Total Solar Eclipse, Erick Agrimson, Kaye Smith, Ana Taylor, Vina Onyango-Robshaw, Rachel Lang, Alynie Xiong, Peace Sinyigaya, Grace Maki, Rachel Dubose, Brittany Craig, James Flaten, Gordon Mcintosh
2017 Academic High Altitude Conference
In preparation for the 2017 total solar eclipse, St. Catherine University developed a calibration protocol for the temperature sensors flown during thermal wake boom experiments. The calibration method used a standard two-point technique that corrected each individual sensor for both slope and offset errors using a high quality NIST certified thermocouple as the temperature standard. Our method is not absolute but corrects each sensor relative to the NIST standard so that we feel some confidence that individual sensor variations are mitigated. In preparation for the eclipse, calibration curves were generated for over 200 individual digital and thermistor temperature sensors.
Controlled Heading Automation Device,
2017
DePaul University
Controlled Heading Automation Device, Robert Coulson
2017 Academic High Altitude Conference
One of the most significant limitations of weather balloon-based data collection is that instruments and payloads cannot depend on particular orientations or predictable rotation. Several investigators have used payload heading control devices to overcome this limitation in order to collect directional data and record motion controlled video footage. The work described in this presentation builds on the Controlled Heading Automation Device (CHAD) developed by Kruger et al. (2016) and was carried out at DePaul University in summer 2017 as an undergraduate research project. Our goal was to record stable video of the shadow of the moon on Earth’s surface during …
Roles Of Cosolvents On Protein Stability,
2017
New Jersey Institute of Technology
Roles Of Cosolvents On Protein Stability, Zhaoqian Su
Dissertations
The function of a protein is determined by its three-dimensional structure which emerges from the delicate balance of forces involving atoms of the protein and the solvent. This balance can be perturbed by changing temperature, pressure, pH and by adding organic molecules known as cosolvents to the solution. Despite the wide use of cosolvents to perturb protein structures in the lab and in living systems, their molecular mechanisms are still not well established. Understanding these mechanisms is a problem of substantial interest, with potential application to the design of new drugs to target proteins. In this dissertation, we probe the …
Evolution Of Superoscillations For Schrödinger Equation In A Uniform Magnetic Field,
2017
Politecnico di Milano
Evolution Of Superoscillations For Schrödinger Equation In A Uniform Magnetic Field, Fabrizio Colombo, Jonathan Gantner, Daniele C. Struppa
Mathematics, Physics, and Computer Science Faculty Articles and Research
Aharonov-Berry superoscillations are band-limited functions that oscillate faster than their fastest Fourier component. Superoscillations appear in several fields of science and technology, such as Aharonov’s weak measurement in quantum mechanics, in optics, and in signal processing. An important issue is the study of the evolution of superoscillations using the Schrödinger equation when the initial datum is a weak value. Some superoscillatory functions are not square integrable, but they are real analytic functions that can be extended to entire holomorphic functions. This fact leads to the study of the continuity of a class of convolution operators acting on suitable spaces of …
Characterization Of Hydrophobic Interactions Of Polymers With Water And Phospholipid Membranes Using Molecular Dynamics Simulations,
2017
CUNY Graduate Center
Characterization Of Hydrophobic Interactions Of Polymers With Water And Phospholipid Membranes Using Molecular Dynamics Simulations, Mihaela Drenscko
Dissertations, Theses, and Capstone Projects
Polymers and lipid membranes are both essential soft materials. The structure and hydrophobicity/hydrophilicity of polymers, as well as the solvent they are embedded in, ultimately determines their size and shape. Understating the variation of shape of the polymer as well as its interactions with model biological membranes can assist in understanding the biocompatibility of the polymer itself. Computer simulations, in particular molecular dynamics, can aid in characterization of the interaction of polymers with solvent, as well as polymers with model membranes. In this thesis, molecular dynamics serve to describe polymer interactions with a solvent (water) and with a lipid membrane. …
Nuclear Magnetic Resonance Studies Of Electrode And Electrolyte Materials For Li-Ion Batteries,
2017
CUNY Graduate Center
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 …
