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Articles 1501 - 1530 of 3451

Full-Text Articles in Physical Sciences and Mathematics

Length Minimizing Network For N Points On The K-Torus, W. Lauritz Petersen, Dr. Denise Halverson Jan 2014

Length Minimizing Network For N Points On The K-Torus, W. Lauritz Petersen, Dr. Denise Halverson

Journal of Undergraduate Research

Our project consisted of several components with the end goal being: given n points on the ktorus (a donut with k number of holes), what would the shortest path network be to connect all the n points (network meaning a network of paths connecting each of the n-points).

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Optimal Energy Recovery In Finite Time For Linearly Dissipative Systems, Mark Meilstrup, Dr. Scott Glasgow Jan 2014

Optimal Energy Recovery In Finite Time For Linearly Dissipative Systems, Mark Meilstrup, Dr. Scott Glasgow

Journal of Undergraduate Research

Many physical processes involve the loss or dissipation of energy. For example, when pushing a box across the floor, some of the energy that is spent will be lost to frictional forces. Our research is concerned with the study of the energy which is lost, and also the energy which is recoverable, in the more complex setting of a linearly dissipative optical system. We consider some electromagnetic pulse, such as a laser beam, entering and interacting with an absorbing medium, such as glass or some gas. When the pulse exits the medium, some of the energy has been absorbed, and …

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Attachment Of Carbon Nanotubes To Atomic Force Microscopy Probe Tips With A Silicon Dioxide Thin-Film, Jed Whittaker, Dr. Robert Davis Jan 2014

Attachment Of Carbon Nanotubes To Atomic Force Microscopy Probe Tips With A Silicon Dioxide Thin-Film, Jed Whittaker, Dr. Robert Davis

Journal of Undergraduate Research

Atomic force microscopy (AFM) is a useful method for obtaining images of surfaces on the nanometer scale. It has been used to image surfaces in many environments, including in atmosphere, vacuum and fluids. The resolution of these images is subject to the size of the probe tip, which is pyramidal. It has been shown that the attachment of a carbon nanotube to an AFM probe tip increases resolution significantly, in both air and fluids1. The nanotubes have initially been attached by Van der Waals forces, individually, which are too weak for applications in fluids. For use in fluids, glues and …

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A Novel Method For The Preparation Of Sulfhydryl-Terminated Self-Assembled Monolayers On Gold, Justin Gregory Peacock, Dr. Matthew R. Linford Jan 2014

A Novel Method For The Preparation Of Sulfhydryl-Terminated Self-Assembled Monolayers On Gold, Justin Gregory Peacock, Dr. Matthew R. Linford

Journal of Undergraduate Research

Self-assembled monolayers (SAM’s) on gold have been extensively studied during the past 20 years because of their use in biochemical surface recognition, as nanotechnological structures, as nano-chemical wires and circuits in electronics, as a means of creating patterned surfaces, as sensors to monitor various chemical levels, and to attach proteins and other biomolecules to surfaces.1 In 1994 Offord et al.2 prepared series of mixed monolayers on gold using different proportions of t-butylthiol and 1-octadecanethiol. When monolayers were prepared from ethanolic solutions, anomalous surface properties were observed at intermediate t-butylthiol solution concentrations. They attributed the higher than expected thicknesses and lower …

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Orca Research Report, Jeanna Chilton, Dr. Gary Lawlor Jan 2014

Orca Research Report, Jeanna Chilton, Dr. Gary Lawlor

Journal of Undergraduate Research

The work I was able to do for the research on the minimal surface area of the octahedron was time consuming, but unfortunately did not bring about any profound knowledge for anyone besides myself.

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Constructing The Remote Observatory For Variable Object Research, Jason A. Gilbert, Dr. J. Ward Moody Jan 2014

Constructing The Remote Observatory For Variable Object Research, Jason A. Gilbert, Dr. J. Ward Moody

Journal of Undergraduate Research

Scientists who attempt to unravel the mysteries of the universe have some physical limitations to deal with in their quest. For example, an observer must stay up all night to operate the telescopes that record the data. There are now automated telescopes that allow the scientist to enter a list of objects (stars, asteroids, planets, galaxies, etc.) into the telescope’s computer, and the telescope will move by itself to each one, taking and recording data throughout the course of the night. Some telescopes can even be operated remotely so the scientists can run them from their offices, or even their …

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Fast Simulation Methods For Electrons In A Penning Trap, Brent A. Chipman, Dr. Ross Spencer Jan 2014

Fast Simulation Methods For Electrons In A Penning Trap, Brent A. Chipman, Dr. Ross Spencer

Journal of Undergraduate Research

The motivation for this work comes from the paper “Parametrically Pumped Electron Oscillators” by J. Tan and G. Gabrielse (1). Tan and Gabrielse describe a number of unexplained behavior exhibited by electrons confined in a parametrically pumped penning trap. In order to gain a better understanding of the mechanisms behind the behavior, numerical simulations of the trap are necessary. Though the equations of motion for the electrons are relatively easy to write and solve, the amount of computing time required makes this approach practically impossible. The purpose of my research was to develop a faster method for solving the problem.

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Measurement Techniques And Computational Methods For Acoustic Data In Concert Halls, Gordon Dix, Dr. Tim Leishman Jan 2014

Measurement Techniques And Computational Methods For Acoustic Data In Concert Halls, Gordon Dix, Dr. Tim Leishman

Journal of Undergraduate Research

Designing and constructing a world-class concert hall is the culmination of many different, yet interrelated, disciplines. The architects must make the building structurally sound, while preserving its aesthetic beauty. Electricity, water, air conditioning, heating, and many other aspects of the inner workings of the hall must be designed and installed properly, while keeping in mind the intent of the structure. Acoustic consultants will often work closely with the architects to ensure that the hall has no acoustic flaws. An acoustical plan for the building must take into account many of the design features of the hall and can become quite …

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Statistical Process Control Methods For Multiple Stream Processes: A Comparative Study, Jared Caleb Christensen, Dr. Scott D. Grimshaw Jan 2014

Statistical Process Control Methods For Multiple Stream Processes: A Comparative Study, Jared Caleb Christensen, Dr. Scott D. Grimshaw

Journal of Undergraduate Research

The Shewhart control chart is the most common statistical process control (SPC) tool used to determine stability. One fundamental assumption of the Shewhart chart is that the output comes from a single, continuous stream. This implies the monitoring of a single source of variation. Filling machines at many beverage plants violate this assumption because there are central filling units with multiple heads filling individual bottles. The variability of the central filling units is the “natural, continuous variability” of the process in terms of a Shewhart chart. The heads add another source of variability. A different methodology needs to be implemented …

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Potential Inhibitors Of Hiv Integrase, Daniel A. Gubler, Dr. Matt A. Peterson Jan 2014

Potential Inhibitors Of Hiv Integrase, Daniel A. Gubler, Dr. Matt A. Peterson

Journal of Undergraduate Research

The purpose of my research is to synthesize a new class of enediynes that mimic linbenzoadenosine derivatives and have potential for inhibiting HIV integrase. This new class of enediynes is shown in Figure 1. Upon synthesis we will evaluate the biological activity of these compounds.

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Multi-Scale Neotectonic Study Of The Clear Lake Fault Zone In The Sevier Desert Basin (Central Utah), Brandon D. Heiner Jan 2014

Multi-Scale Neotectonic Study Of The Clear Lake Fault Zone In The Sevier Desert Basin (Central Utah), Brandon D. Heiner

Theses and Dissertations

A multi-scale high-resolution geophysical and geological study was conducted in the Sevier Desert, central Utah, found within the Colorado Plateau-Basin and Range Transition Zone. The region is marked by with Quaternary volcanics and faulting as young as 660 yr B.P., with many fault scarps thought to have the potential for 7+ magnitude earthquakes. Three locations within the Sevier Desert which represent three different tectonic expressions of possible faulting at the surface were selected. These include a location found within surface sedimentation, a location with surface sedimentation and sub-surface basalts and a location with basalts, at the surface with very limited …

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Collisional Dynamic Elements Of The Pyrazine - N2o System:Middle And Low J States, La Moyne Tyler Mix Jan 2014

Collisional Dynamic Elements Of The Pyrazine - N2o System:Middle And Low J States, La Moyne Tyler Mix

Theses and Dissertations

Unimolecular reactions based on the Lindemann - Hinchelwood mechanism are important to understanding combustion and atmospheric processes. The main feature of this mechanism is the energy transfer probability distribution function, P(E',E). We have chosen to study P(E',E) through gas phase collisional dynamics probed with IR transient absorption spectroscopy. Post-collision absorption line widths for the pyrazine-N2O system are used to calculate lab frame translational temperatures. The translational temperatures reveal that collisions with large rotational energy transfer also transfer large amounts of translational energy. For J states >47 the relationship is linear indicating a constant impact parameter. Line widths for J=47 through …

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How Well Does Multiple Ocr Error Correction Generalize?, William B. Lund, Eric K. Ringger, Daniel D. Walker Jan 2014

How Well Does Multiple Ocr Error Correction Generalize?, William B. Lund, Eric K. Ringger, Daniel D. Walker

Faculty Publications

As the digitization of historical documents, such as newspapers, becomes more common, the need of the archive patron for accurate digital text from those documents increases. Building on our earlier work, the contributions of this paper are: 1. in demonstrating the applicability of novel methods for correcting optical character recognition (OCR) on disparate data sets, including a new synthetic training set, 2. enhancing the correction algorithm with novel features, and 3. assessing the data requirements of the correction learning method. First, we correct errors using conditional random fields (CRF) trained on synthetic training data sets in order to demonstrate the …

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A Mathematical Model Of Collagen Lattice Contraction, J. C. Dallon, Emily J. Evans, H Paul Erhlich Jan 2014

A Mathematical Model Of Collagen Lattice Contraction, J. C. Dallon, Emily J. Evans, H Paul Erhlich

Faculty Publications

Two mathematical models for fibroblast-collagen interaction are proposed which reproduce qualitative features of fibroblast populated collagen lattice contraction in time. Both models are force based and model the cells as individual entities with discrete attachment sites however the collagen lattice is modeled differently for each model. In the collagen lattice model the lattice is more interconnected and formed by triangulating nodes to form the fibrous structure. In the collagen fiber model the nodes are not triangulated, are less interconnected, and the collagen fibers are modeled as a string of nodes. Both models suggest that the overall increase in stress of …

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Counting Threshold Graphs And Finding Inertia Sets, Christopher Abraham Guzman Dec 2013

Counting Threshold Graphs And Finding Inertia Sets, Christopher Abraham Guzman

Theses and Dissertations

This thesis is separated into two parts: threshold graphs and inertia sets. First we present an algorithmic approach to finding the minimum rank of threshold graphs and then progress to counting the number of threshold graphs with a specific minimum rank. Second, we find an algorithmic and more automated way of determining the inertia set of graphs with seven or fewer vertices using theorems and lemmata found in previous papers. Inertia sets are a relaxation of the inverse eigenvalue problem. Instead of determining all the possible eigenvalues that can be obtained by matrices with a specific zero/nonzero pattern we restrict …

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The Role Of Defects In Interlayer Cation Exchange In Clay Minerals, Laura Cardon, Dr. Barry R. Bickmore Dec 2013

The Role Of Defects In Interlayer Cation Exchange In Clay Minerals, Laura Cardon, Dr. Barry R. Bickmore

Journal of Undergraduate Research

Clay minerals comprise a large portion of the abundant sediment that covers the earth’s surface. As such, they have a significant impact on society in regard to land development and also water and mineral resources. The purpose of this study was to help unravel the mysteries of clay mineral properties by focusing special attention on the effects of defects found in the clay mineral structure. These defects are believed to play a key role in the exchange of, oftentimes toxic, interlayer cations in the clay mineral. Better understanding of this exchange would lead to better water management and aid us …

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Development And Validation Of An Automated Directivity Acquisition System Used In The Acquisition, Processing, And Presentation Of The Acoustic Far-Field Directivity Of Musical Instruments In An Anechoic Space, Nicholas J. Eyring Dec 2013

Development And Validation Of An Automated Directivity Acquisition System Used In The Acquisition, Processing, And Presentation Of The Acoustic Far-Field Directivity Of Musical Instruments In An Anechoic Space, Nicholas J. Eyring

Theses and Dissertations

A high spatial resolution acoustic directivity acquisition system (ADAS) has been developed to acquire anechoic measurements of the far field radiation of musical instruments that are either remote controlled or played by musicians. Building upon work performed by the BYU Acoustic Research Group in the characterization of loudspeaker directivity, one can rotate a musical instrument with sequential azimuthal angle increments under a fixed semicircular array of microphones while recording repeated notes or sequences of notes. This results in highly detailed and instructive directivity data presented in the form of high-resolution balloon plots. The directivity data and corresponding balloon plots may …

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Synthesis, Characterization, And Application Of High Surface Area, Mesoporous, Stabilized Anatase Tio2 Catalyst Supports, Rebecca Elizabeth Olsen Dec 2013

Synthesis, Characterization, And Application Of High Surface Area, Mesoporous, Stabilized Anatase Tio2 Catalyst Supports, Rebecca Elizabeth Olsen

Theses and Dissertations

Nanomaterials have attracted substantial attention in the area of catalysis due to the unique properties they exhibit such as high surface areas, intricate pore networks and unique morphologies. TiO2 has attracted attention as a catalyst since the discovery of its high photocatalytic activity by Fuishima and Honda in 1972. Given its high thermal stability, low cost, low environmental impact, and versatility, TiO2 is a widely used commercial catalyst and catalyst support. TiO2 is used in many applications such as photocatalysis is also an excellent support material for noble metals in a number of oxidative synthesis and pollution-control reactions. Though TiO2 …

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Geology Of The Birdseye 7.5-Minute Quadrangle, Utah County, Utah:Â Implications For Mid-Cenozoic Extension And Deposition Of The Moroni Formation, Don L. Bagshaw Dec 2013

Geology Of The Birdseye 7.5-Minute Quadrangle, Utah County, Utah:Â Implications For Mid-Cenozoic Extension And Deposition Of The Moroni Formation, Don L. Bagshaw

Theses and Dissertations

Geologic structures within the Birdseye 7.5 minute quadrangle Utah County, Utah have been related by previous workers to both the Jurassic Arapien Shale diapirism and to the mid-Cenozoic extensional collapse of the Charleston-Nebo Thrust. Whichever model proves valid, it will have implications for oil exploration and interpretation of the subsurface geologic structure in the region. A detailed map of the quadrangle was constructed to better constrain which mechanism was responsible for the deformation. Exposures of Arapien Shale near, and within the Birdseye quadrangle show no evidence of diapiric movement. Arapien involvement in the deformation of Tertiary rocks in the center …

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Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson Dec 2013

Nonlinear Spectroscopic Investigation Of Adsorption To C-18 Model Stationary Phase, Anthony D. Peterson

Theses and Dissertations

Reversed-phase liquid chromatography (RPLC) is a commonly used separation technique in chemistry. Nevertheless, the mechanistic interactions at the molecular level among the eluent, analyte, and the stationary phase are not fully understood. Because of this limited understanding, optimization of the separation must be done experimentally. Learning more about molecular interactions should aid in improving separations. We are currently using second-harmonic generation (SHG) spectroscopy to investigate how analytes adsorb to the surface. SHG is a spectroscopic technique that produces signal only at places of non-isotropic symmetry; this typically occurs at surfaces. SHG can be used to produce surface isotherms of test …

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Record Linkage, Stasha Ann Bown Larsen Dec 2013

Record Linkage, Stasha Ann Bown Larsen

Theses and Dissertations

This document explains the use of different metrics involved with record linkage. There are two forms of record linkage: deterministic and probabilistic. We will focus on probabilistic record linkage used in merging and updating two databases. Record pairs will be compared using character-based and phonetic-based similarity metrics to determine at what level they match. Performance measures are then calculated and Receiver Operating Characteristic (ROC) curves are formed. Finally, an economic model is applied that returns the optimal tolerance level two databases should use to determine a record pair match in order to maximize profit.

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Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich Dec 2013

Digital Outcrop Model And Paleoecology Of The Eight-Foot Rapid Algal Field (Middle Pennsylvanian Lower Ismay Sequence), Paradox Basin, Utah, Colton Lynn Goodrich

Theses and Dissertations

Although phylloid algal mounds have been studied for 50 year, much remains to be determined concerning the ecology and sedimentology of these Late Paleozoic carbonate buildups. Herein we perform a digital outcrop study of the well-known Middle Pennsylvanian Lower Ismay mound interval in the Paradox Basin because outcropping mounds along the San Juan River are cited as outcrop analogs of reservoir carbonates in the Paradox Basin oil province of Utah and adjacent states. The principal field area is the Eight Foot algal field located at river mile 19.2 on the San Juan River, approximately 14 miles SSW of Bluff, Utah. …

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Minimum Rank Problems For Cographs, Nicole Andrea Malloy Dec 2013

Minimum Rank Problems For Cographs, Nicole Andrea Malloy

Theses and Dissertations

Let G be a simple graph on n vertices, and let S(G) be the class of all real-valued symmetric nxn matrices whose nonzero off-diagonal entries occur in exactly the positions corresponding to the edges of G. The smallest rank achieved by a matrix in S(G) is called the minimum rank of G, denoted mr(G). The maximum nullity achieved by a matrix in S(G) is denoted M(G). For each graph G, there is an associated minimum rank class, MR(G) consisting of all matrices A in S(G) with rank A = mr(G). Although no restrictions are applied to the diagonal entries of …

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Formation And Analysis Of Zinc Oxide Nanoparticles And Zinc Oxide Hexagonal Prisms And Optical Analysis Of Cadmium Selenide Nanoparticles, Jared M. Hancock Dec 2013

Formation And Analysis Of Zinc Oxide Nanoparticles And Zinc Oxide Hexagonal Prisms And Optical Analysis Of Cadmium Selenide Nanoparticles, Jared M. Hancock

Theses and Dissertations

In this dissertation, methods to synthesize ZnO are reported. First, zinc oxide nanoparticles were synthesized with small amounts of transition metal ions to create materials called dilute magnetic semiconductors (DMS). We employed a low temperature sol-gel method that produces ZnO nanoparticles of reproducible size and incorporates cobalt, nickel, and manganese ions into the nanoparticles. Conditions were controlled such that a range of amounts of Co, Ni, and Mn were incorporated. The incorporation was tracked by color changes in the white ZnO powder to blue for Co, green for Ni and yellow for Mn. XRD measurements showed the nanoparticles were on …

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Ferritin-Based Photo-Oxidation Of Biomass For Nanoparticle Synthesis, Bioremediation, And Hydrogen Evolution, Oscar Petrucci Dec 2013

Ferritin-Based Photo-Oxidation Of Biomass For Nanoparticle Synthesis, Bioremediation, And Hydrogen Evolution, Oscar Petrucci

Theses and Dissertations

The cell is the basic unit of all living organisms. It is an amazing machine capable of self-replicating, growing, and synthesizing and shuttling thousands of compounds. To perform all of these activities the cell needs energy. The original source of energy for all living beings is the Sun. The energy of the sun is collected by the autotrophs (mostly plants) through photosynthesis and stored in the chemical bonds of carbohydrates and lipids through carboxylic acid intermediates; animals use these compounds to obtain the energy for their cells. Most of the energy extracted by the cell comes from the citric acid …

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Obstacles And Solutions To Studying Functional Adhesives Using Vibrational Sum-Frequency Generation Spectroscopy, Angela Renee Andersen Dec 2013

Obstacles And Solutions To Studying Functional Adhesives Using Vibrational Sum-Frequency Generation Spectroscopy, Angela Renee Andersen

Theses and Dissertations

Important aspects of adhesion occur at interfaces, including structures that may be different from those in the bulk materials. However, probing the orientation of molecules in functional adhesives poses a significant challenge because adhesive molecules are always located at a buried interface. The limited penetration depth of surface-specific analysis prohibits the study of buried interfaces using those techniques. The large quantity of bulk molecules relative to the adhesive molecules interacting at the interface results in the bulk signal swamping out adhesive signal in bulk analysis techniques. An interface-specific technique is required to study functional adhesives. One such technique that has …

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Investigation Into The Effects Of Pegylation On The Thermodynamic Stability Of The Ww Domain, Sam S. Matthews Dec 2013

Investigation Into The Effects Of Pegylation On The Thermodynamic Stability Of The Ww Domain, Sam S. Matthews

Theses and Dissertations

The covalent attachment of poly(ethylene glycol) (PEG) to a protein surface (known as PEGylation), has been demonstrated to increase the serum half-life of therapeutic proteins by reducing kidney clearance and immunogenicity and by protecting against proteolysis. Theses beneficial effects could be further enhanced if PEGylation consistently increased protein conformational stability (i.e. the difference in free energy between the folded and unfolded states). However, the effects of PEGylation on protein conformational stability are unpredictable; PEGylation has been reported to increase, decrease, or have no effect on the conformational stability of medicinal proteins.This thesis details the results of two studies aimed at …

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Shaping Swarms Through Coordinated Mediation, Shin-Young Jung Dec 2013

Shaping Swarms Through Coordinated Mediation, Shin-Young Jung

Theses and Dissertations

A swarm is a group of uninformed individuals that exhibit collective behaviors. Without any information about the external world, a swarm has limited ability to achieve complex goals. Prior work on human-swarm interaction methods allow a human to influence these uninformed individuals through either leadership or predation as informed agents that directly interact with humans. These methods of influence have two main limitations: (1) although leaders sustain influence over nominal agents for a long period of time, they tend to cause all collective structures to turn in to flocks (negating the benefit of other swarm formations) and (2) predators tend …

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The Pseudo-Rigid-Body Model For Fast, Accurate, Non-Linear Elasticity, Anthony R. Hall Nov 2013

The Pseudo-Rigid-Body Model For Fast, Accurate, Non-Linear Elasticity, Anthony R. Hall

Theses and Dissertations

We introduce to computer graphics the Pseudo-Rigid-Body Mechanism (PRBM) and the chain algorithm from mechanical engineering, with a unified tutorial from disparate source materials. The PRBM has been used successfully to simplify the simulation of non-linearly elastic beams, using deflections of an analogous spring and rigid-body linkage. It offers computational efficiency as well as an automatic parameterization in terms of physically measurable, intuitive inputs which fit naturally into existing animation work flows for character articulation. The chain algorithm is a technique for simulating the deflection of complicated elastic bodies in terms of straight elastic elements, which has recently been extended …

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Acoustic Droplet Vaporization In Biology And Medicine, Chung-Yin Lin, William G. Pitt Nov 2013

Acoustic Droplet Vaporization In Biology And Medicine, Chung-Yin Lin, William G. Pitt

Faculty Publications

This paper reviews the literature regarding the use of acoustic droplet vaporization (ADV) in clinical applications of imaging, embolic therapy, and therapeutic delivery. ADV is a physical process in which the pressure waves of ultrasound induce a phase transition that causes superheated liquid nanodroplets to form gas bubbles. The bubbles provide ultrasonic imaging contrast and other functions. ADV of perfluoropentane was used extensively in imaging for preclinical trials in the 1990s, but its use declined rapidly with the advent of other imaging agents. In the last decade, ADV was proposed and explored for embolic occlusion therapy, drug delivery, aberration correction, …

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