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Full-Text Articles in Physical Sciences and Mathematics

Seasonal Controls On Nearshore Hypoxia In A Small Coastal Embayment, Stephen Alexander Huie Mar 2021

Seasonal Controls On Nearshore Hypoxia In A Small Coastal Embayment, Stephen Alexander Huie

Physics

Dissolved oxygen (DO) is an important biogeochemical factor that strongly influences nearshore coastal ecosystems. Low DO (hypoxic) events can cause physiological stressful environments for ecological and economically important species, potentially leading to mass mortalities. In order to better assess drivers of coastal hypoxia, we collected data from monthly cruises on the inner shelf and nearshore moorings inside and outside a small coastal embayment (San Luis Obispo Bay on the Central California Coast) across the full upwelling season (March to August). During the late spring and early summer, we found that the nearshore near-bottom temperature-DO (T-DO) relationship aligned with the shelf ...


Quantum Computing: Resolving Myths, From Physics To Metaphysics, Jacob R. Mandel Mar 2021

Quantum Computing: Resolving Myths, From Physics To Metaphysics, Jacob R. Mandel

Physics

As the field of quantum computing becomes popularized, myths or misconceptions will inevitably come along with it. From the sci-fi genre to the casual usage of the term quantum, idealism begins to take over our projections of the technological future. But what are quantum computers? And what does quantum mean? How are they any different than the computers we use on an everyday basis? Will there be quantum computing smartphones? Are quantum computers just a faster version of conventional computing or a wholly new way of computing altogether? The objective of this paper is to resolve common myths or misconceptions ...


Potential Environmental Effects Of Deepwater Floating Offshore Wind Energy Facilities, Hayley Farr, Benjamin Ruttenberg, Ryan K. Walter, Yi-Hui Wang, Crow White Mar 2021

Potential Environmental Effects Of Deepwater Floating Offshore Wind Energy Facilities, Hayley Farr, Benjamin Ruttenberg, Ryan K. Walter, Yi-Hui Wang, Crow White

Physics

Over the last few decades, the offshore wind energy industry has expanded its scope from turbines mounted on foundations driven into the seafloor and standing in less than 60 m of water, to floating turbines moored in 120 m of water, to prospecting the development of floating turbines moored in ~1,000 m of water. Since there are few prototype turbines and mooring systems of these deepwater, floating offshore wind energy facilities (OWFs) currently deployed, their effects on the marine environment are speculative. Using the available scientific literature concerning appropriate analogs, including fixed-bottom OWFs, land-based wind energy facilities, wave and ...


Ultrafast Investigation And Control Of Dirac And Weyl Semimetals, Christopher P. Weber Feb 2021

Ultrafast Investigation And Control Of Dirac And Weyl Semimetals, Christopher P. Weber

Physics

Ultrafast experiments using sub-picosecond pulses of light are poised to play an important role in the study and use of topological materials and, particularly, of the three-dimensional Dirac and Weyl semimetals. Many of these materials’ characteristic properties—their linear band dispersion, Berry curvature, near-vanishing density of states at the Fermi energy, and sensitivity to crystalline and time-reversal symmetries—are closely related to their sub- and few-picosecond response to light. Ultrafast measurements offer the opportunity to explore excitonic instabilities and transient photocurrents, the latter depending on the Berry curvature and possibly quantized by fundamental constants. Optical pulses may, through Floquet effects ...


The Structure Function Relationship Of Disordered Networks Using Young's Modulus And Floppy Modes, Melinda Grace Tajnai Feb 2021

The Structure Function Relationship Of Disordered Networks Using Young's Modulus And Floppy Modes, Melinda Grace Tajnai

Physics

Disordered networks may have the ability to store information that can be retrieved using a Young’s modulus measurement. The effect of the number of floppy modes a network has on the value of this Young’s modulus measurement is unknown. This experiment uses 28 networks consisting of 3D printed edges in a sliding frame to determine how the Young’s modulus of a network is related to the number of floppy modes.


Effects Of Estuary-Wide Seagrass Loss On Fish Populations, Jennifer K. O'Leary, Maurice C. Goodman, Ryan K. Walter, Kariss Willits, Daniel J. Pondella Jan 2021

Effects Of Estuary-Wide Seagrass Loss On Fish Populations, Jennifer K. O'Leary, Maurice C. Goodman, Ryan K. Walter, Kariss Willits, Daniel J. Pondella

Physics

Globally, habitat loss in coastal marine systems is a major driver of species decline, and estuaries are particularly susceptible to loss. Along the United States Pacific coast, monospecific eelgrass (Zostera marina) beds form the major estuarine vegetated habitat. In Morro Bay, California, eelgrass experienced an unprecedented decline of > 95%, from 139 ha in 2007 to < 6 ha by 2017. Fish populations were compared before and after the eelgrass decline using trawl surveys. Beach seines surveys were also conducted during the post-decline period to characterize species within and outside of remnant eelgrass beds.While the estuary-wide loss of eelgrass did not result in fewer fish or less biomass, it led to changes in species composition. The post-eelgrass decline period was characterized by increases in flatfish (mainly Citharichthys stigmaeus) and staghorn sculpin (Leptocottus armatus), and decreases in habitat specialists including bay pipefish (Syngnathus leptorhynchus) and shiner perch (Cymatogaster aggregata). There were similar trends inside and outside of remnant eelgrass patches. These findings support evidence across multiple ecosystems suggesting that the predominance of habitat-specialists predicts whether or not habitat loss leads to an overall decline in fish abundance. In addition, loss of critical habitats across seascapes can restrict population connectivity and lead to range contraction. For bay pipefish, the loss of eelgrass in Morro Bay is likely to create a population biogeographic divide. Currently, Morro Bay is dominated by flatfish and sculpins, and the longevity of this new ecosystem state will depend on future eelgrass recovery dynamics supported by ecosystem-based management approaches.


Seasonal Variability Of Upwelling And Downwelling Surface Current Patterns Near A Small Coastal Embayment, Nicholas Trautman Dec 2020

Seasonal Variability Of Upwelling And Downwelling Surface Current Patterns Near A Small Coastal Embayment, Nicholas Trautman

Physics

Upwelling in coastal embayments is important to a variety of physical and biological processes. Despite their ubiquity, circulation patterns in small bays (width and length scales ≤ 20 km) in eastern boundary current upwelling systems are relatively understudied compared to their larger counterparts. In this study, we apply a conditional averaging technique to investigate upwelling- and downwelling-driven circulation in a small coastal embayment located in Central California [San Luis Obispo (SLO) Bay]. We also investigate intraseasonal differences in the current patterns in SLO Bay. Conditional averaging reveals distinct intraseasonal differences and features that are obscured by traditional seasonal averages when examining ...


Machine Learning Based Predictions Of Dissolved Oxygen In A Small Coastal Embayment, Manuel Valera, Ryan K. Walter, Barbara A. Bailey, Jose E. Castillo Dec 2020

Machine Learning Based Predictions Of Dissolved Oxygen In A Small Coastal Embayment, Manuel Valera, Ryan K. Walter, Barbara A. Bailey, Jose E. Castillo

Physics

Coastal dissolved oxygen (DO) concentrations have a profound impact on nearshore ecosystems and, in recent years, there has been an increased prevalance of low DO hypoxic events that negatively impact nearshore organisms. Even with advanced numerical models, accurate prediction of coastal DO variability is challenging and computationally expensive. Here, we apply machine learning techniques in order to reconstruct and predict nearshore DO concentrations in a small coastal embayment while using a comprehensive set of nearshore and offshore measurements and easily measured input (training) parameters. We show that both random forest regression (RFR) and support vector regression (SVR) models accurately reproduce ...


Using Current-Voltage Characteristics To Probe The Transport Mechanism In Carbon Nanotube Networks, Alejandro Jimenez Nov 2020

Using Current-Voltage Characteristics To Probe The Transport Mechanism In Carbon Nanotube Networks, Alejandro Jimenez

Physics

Carbon nanotube (CNT) random networks have shown great promise in electronic applications. For example, they have been used as the active layer in thin film transistor biosensors and as electrodes in supercapacitors (Hu, 2010). Although CNT networks applications are numerous, some of the key details of their electrical behavior are not fully understood. In particular, it is known that the junctions between tubes in CNT networks play a key role in determining the sensing properties of the network (Thanihaichelvana, et al., 2018), however, the mechanism by which metallic-semiconducting (m-s) tube junctions affect the electrical sensing properties of the network is ...


Variability Of Active Galactic Nuclei From Differential Photometry, Nicholas Steven Yee Sep 2020

Variability Of Active Galactic Nuclei From Differential Photometry, Nicholas Steven Yee

Physics

The Seoul AGN Monitoring Project, or SAMP for short, is an international project (PI Jonghak Woo from Korea) with the goal of measuring the masses of black holes residing in the center of massive active galactic nuclei (AGNs). AGNs are some of the brightest objects in the universe. Their light is attributed to the accretion of material onto the black hole. However, these objects are too distant to spatially resolve the gravitational sphere of influence of the black hole directly. Instead, we use a technique called reverberation mapping which observes the variability of the AGN power-law continuum emission and the ...


Abalone Recruitment In Abalone Recruitment In Low-Density And Aggregated Populations Facing Climatic Stress, Ryan K. Walter Aug 2020

Abalone Recruitment In Abalone Recruitment In Low-Density And Aggregated Populations Facing Climatic Stress, Ryan K. Walter

Physics

Understanding spatial and temporal patterns in the recruitment of marine invertebrates with complex life histories remains a critical knowledge gap in marine ecology and fisheries. As marine invertebrates are facing multiple stressors from overfishing and climatic stress, it is important to evaluate the conditions that facilitate recruitment in low-density populations. The red abalone Haliolis rufescens historically supported an economically important fishery in California, but the fishery was sequentially closed as stocks declined, and the last fished area was closed in 2018 following the collapse of the kelp forests in Northern California. Here, red abalone recruitment was evaluated annually from 2012 ...


Cooking Systems Using Aluminum Foam, Ryan Tetsuo Mizukami Aug 2020

Cooking Systems Using Aluminum Foam, Ryan Tetsuo Mizukami

Physics

In developing countries, the use of wood burning fires for cooking is cause for illness and death. With this in mind, research was conducted to develop a solar cooking device capable of cooking of soup within 15 mins in order to reduce the negative impacts of cooking with wood. Current methods of solar-based cooking, such as solar concentrators and solar tube ovens, are impractical. A small solar panel is a cost-effective way to produce energy but will not produce enough power to cook within a reasonable amount of time. Even if it is assumed that all of the energy produced ...


Learning Assistant And Instructor Communication: Impacts On Perceived Efficacy, Jahangir Rassouli, Laura Ríos Jul 2020

Learning Assistant And Instructor Communication: Impacts On Perceived Efficacy, Jahangir Rassouli, Laura Ríos

Physics

The Learning Assistant (LA) Model was co-developed by Richard McCray and Valerie Otero at the University of Colorado Boulder in 2003. In this model, senior undergraduate students serve as facilitators for group discussion in lower-division courses, and employ evidenced-based practices for promoting inquiry and active learning [1]. Since its inception, the LA model has grown to various departments, disciplines, and universities.

At California Polytechnic State University San Luis Obispo (Cal Poly), the LA program in the physics department is still in its early stages. As such, it is an environment rich for exploration into the affordances, limitations, and benefits of ...


Temperature And Salinity Distributions And Flushing Time Estimates In A Low-Inflow California Estuary, Sydney N. Wewerka Jun 2020

Temperature And Salinity Distributions And Flushing Time Estimates In A Low-Inflow California Estuary, Sydney N. Wewerka

Physics

This study examines the temperature and salinity distributions in Morro Bay, a small, seasonally LIE located on the central coast of California. In Morro Bay, eelgrass (Zostera marina; a temperate seagrass), like all seagrasses, is a critical habitat-forming species that supports a large variety of invertebrate, fish, and bird species in the estuary (MBNEP, 2018). Since 2007, eelgrass in the estuary has declined by over 90%, with most losses occurring in the back regions (i.e., head) of the estuary (MBNEP, 2018). Near the mouth, eelgrass meadows have remained resilient, indicating that gradients in environmental conditions throughout the bay may ...


Quantum Random Walk Search And Grover's Algorithm - An Introduction And Neutral-Atom Approach, Anna Maria Houk Jun 2020

Quantum Random Walk Search And Grover's Algorithm - An Introduction And Neutral-Atom Approach, Anna Maria Houk

Physics

In the sub-field of quantum algorithms, physicists and computer scientist take classical computing algorithms and principles and see if there is a more efficient or faster approach implementable on a quantum computer, i.e. a ”quantum advantage”. We take random walks, a widely applicable group of classical algorithms, and move them into the quantum computing paradigm. Additionally, an introduction to a popular quantum search algorithm called Grover’s search is included to guide the reader to the development of a quantum search algorithm using quantum random walks. To close the gap between algorithm and hardware, we will look at using ...


Corrosion Prevention, Matthew Walker Jun 2020

Corrosion Prevention, Matthew Walker

Physics

In Insulated Solar Electric Cooking (ISEC), heating is done by passing current through a chain of diodes directly connected to a solar panel (Gius et al, 2019). It is crucially important that the wires remain conducting, but not conduct to any metal surface that might short the heating circuit. Corrosion of any wires will cause a loosening of the mechanical (twisted) wire connection and could result in a loss of electrical connection completely, or undesired increased resistance.


An Investigation Of Diode Failure, Nicholas James Adams May 2020

An Investigation Of Diode Failure, Nicholas James Adams

Physics

Solar electricity can be used to cheaply cook food and charge electronic devices. We investigate the viability of using diodes as heating elements for insulated solar electric cooking (ISEC). In addition, information on designing and constructing ISEC compatible phone chargers and rechargeable LED lighting systems is included.


Viable Renewable Energy Sources And Storage For The Retired Power Plant In Morro Bay, Ca, Teresa Netro May 2020

Viable Renewable Energy Sources And Storage For The Retired Power Plant In Morro Bay, Ca, Teresa Netro

Physics

This project will investigate renewable energy production and storage options possible for the Morro Bay Power Plant and provide a recommendation for the energy portfolio of the renovated site. These suggestions can be tested at the Morro Bay facility before being extended to the nearby Diablo Nuclear Power Plant.


Formation Pathways In Brightest Cluster Galaxies: Measuring The Distribution Of Ages, Metallicities, And Hydrodynamics Of Stellar Populations, Priscilla E. Holguin West May 2020

Formation Pathways In Brightest Cluster Galaxies: Measuring The Distribution Of Ages, Metallicities, And Hydrodynamics Of Stellar Populations, Priscilla E. Holguin West

Physics

Brightest Cluster Galaxies (BCGs) are the most massive galaxies in the local universe and have had the full age of the universe to build. This makes their formation and evolution history particularly interesting as they offer a glimpse at potential evolutionary pathways for younger systems. We present the radial profile of ages, metallicities, and preliminary classification of companions to 23 BCGs observed using the SparsePak instrument on WIYN by running the STARLIGHT stellar population synthesis models. This analysis of the BCGs’ stellar populations is done by separating each BCG into different regions, and preliminary results of the stellar populations for ...


An Overview Of Lasers And Their Applications, Luis Cristian Giovanni Guerrero May 2020

An Overview Of Lasers And Their Applications, Luis Cristian Giovanni Guerrero

Physics

This paper is an overview of lasers and their applications. The fundamentals of laser operation are covered as well as the various applications of advanced laser systems. The primary focus is to highlight some of the technological advancements made possible by lasers in the last half-century.


Seasonal And Interannual Variability Of Phytoplankton Abundance And Community Composition On The Central Coast Of California, Alex Barth, Ryan K. Walter, Ian C. Robbins, Alexis Pasulka Mar 2020

Seasonal And Interannual Variability Of Phytoplankton Abundance And Community Composition On The Central Coast Of California, Alex Barth, Ryan K. Walter, Ian C. Robbins, Alexis Pasulka

Physics

Variations in the abundance and composition of phytoplankton greatly impact ecosystem structure and function. Within the California Current System (CCS), phytoplankton community structure is tightly coupled to seasonal variability in wind-driven coastal upwelling, a process that drives changes in coastal water temperatures and nutrient concentrations. Based on approximately a decade (2008-2018) of weekly phytoplankton measurements, this study provides the first characterization of the seasonal and interannual variability of phytoplankton abundance and composition in San Luis Obispo (SLO) Bay, an understudied region within the CCS. Overall, the seasonality of phytoplankton in SLO Bay mirrored that of the larger CCS; diatoms dominated ...


Host-Galaxy Morphology Of 14 Local Active Galaxies As Imaged By The Hubble Space Telescope, Tomas Henry Snyder Mar 2020

Host-Galaxy Morphology Of 14 Local Active Galaxies As Imaged By The Hubble Space Telescope, Tomas Henry Snyder

Physics

Active galactic nuclei (AGNs) are galaxies with super-massive black holes, that are undergoing accretion, at their centers. The study of these objects provides us with a deeper understanding of how the black holes evolved along with their host galaxies since black hole mass is highly correlated with bulge mass. A sample of 66 AGNs were imaged using the Hubble Space Telescope (HST) and 14 of those are analyzed in this paper to determine their structure, bulge luminosity, and bulge type. The program GALFIT is implemented to determine these parameters, that will be used in further research in the future. These ...


Optimizing Llrf Parameters In The Electron-Ion Collider, William M. Bjorndahl Mar 2020

Optimizing Llrf Parameters In The Electron-Ion Collider, William M. Bjorndahl

Physics

To improve particle interaction in the future Electron-Ion Collider (EIC), we investigated different feedback implementations to control the accelerating voltage and examined the power and beam phase for each instance. Using MATLAB, we studied three feedback mechanisms: Direct, One Turn, and Feedforward. Enacting feedforward yielded the best performance. To minimize the klystron power consumption, we analyzed different Low-Level Radio Frequency (LLRF) parameters such as detuning. Combining theory and simulated results, we found the optimal detuning value that minimizes klystron power consumption.


An Introduction To Shape Dynamics, Patrick R. Kerrigan Nov 2019

An Introduction To Shape Dynamics, Patrick R. Kerrigan

Physics

Shape Dynamics (SD) is a new fundamental framework of physics which seeks to remove any non-relational notions from its methodology. importantly it does away with a background space-time and replaces it with a conceptual framework meant to reflect direct observables and recognize how measurements are taken. It is a theory of pure relationalism, and is based on different first principles then General Relativity (GR). This paper investigates how SD assertions affect dynamics of the three body problem, then outlines the shape reduction framework in a general setting.


Spatial And Temporal Variation Of Offshore Wind Power And Its Values Along The Central California Coast, Yi-Hui Wang, Ryan K. Walter, Crow White, Matthew D. Kehrli, Stephen F. Hamilton, Patrick H. Soper, Benjamin I. Ruttenberg Oct 2019

Spatial And Temporal Variation Of Offshore Wind Power And Its Values Along The Central California Coast, Yi-Hui Wang, Ryan K. Walter, Crow White, Matthew D. Kehrli, Stephen F. Hamilton, Patrick H. Soper, Benjamin I. Ruttenberg

Physics

The analysis of the spatiotemporal variability of wind power remains limited during the planning stage of an offshore wind farm. This study provides a framework to investigate how offshore wind power varies along the Central California Coast over diurnal and seasonal time scales, which is critical for reliability and functionality of the grid system. We find that offshore wind power in this region peaks during evening hours across all seasons and maximizes in spring and summer. The timing of peak offshore wind power production better aligns with that of peak demand across California than solar and land-based wind power production ...


Space Telescope And Optical Reverberation Mapping Project. Viii. Time Variability Of Emission And Absorption In Ngc5548 Based On Modeling The Ultraviolet Spectrum, G. A. Kriss, G. De Rosa, J. Ely, B. M. Peterson, Vardha Nicola Bennert, Y. Zu Aug 2019

Space Telescope And Optical Reverberation Mapping Project. Viii. Time Variability Of Emission And Absorption In Ngc5548 Based On Modeling The Ultraviolet Spectrum, G. A. Kriss, G. De Rosa, J. Ely, B. M. Peterson, Vardha Nicola Bennert, Y. Zu

Physics

We model the ultraviolet spectra of the Seyfert 1 galaxy NGC 5548 obtained with the Hubble Space Telescope during the 6 month reverberation mapping campaign in 2014. Our model of the emission from NGC 5548 corrects for overlying absorption and deblends the individual emission lines. Using the modeled spectra, we measure the response to continuum variations for the deblended and absorption-corrected individual broad emission lines, the velocity-dependent profiles of Lyα and C iv, and the narrow and broad intrinsic absorption features. We find that the time lags for the corrected emission lines are comparable to those for the original ...


A Single Fast Radio Burst Localized To A Massive Galaxy At Cosmological Distance, K. W. Bannister, A. T. Deller, C. Phillips, J.-P. Macquart, Vardha Nicola Bennert, C. D. Wilson Aug 2019

A Single Fast Radio Burst Localized To A Massive Galaxy At Cosmological Distance, K. W. Bannister, A. T. Deller, C. Phillips, J.-P. Macquart, Vardha Nicola Bennert, C. D. Wilson

Physics

Fast radio bursts (FRBs) are brief radio emissions from distant astronomical sources. Some are known to repeat, but most are single bursts. Nonrepeating FRB observations have had insufficient positional accuracy to localize them to an individual host galaxy. We report the interferometric localization of the single-pulse FRB 180924 to a position 4 kiloparsecs from the center of a luminous galaxy at redshift 0.3214. The burst has not been observed to repeat. The properties of the burst and its host are markedly different from those of the only other accurately localized FRB source. The integrated electron column density along the ...


Jet-Driven Galaxy-Scale Gas Outflows In The Hyperluminous Quasar 3c 273, Bernd Husemann, Vardha Nicola Bennert, Knud Jahnke, Timothy A. Davis, Jong-Hak Woo, Julia Scharwächter, Andreas Schulze, Massimo Gaspari, Martin A. Zwaan Jul 2019

Jet-Driven Galaxy-Scale Gas Outflows In The Hyperluminous Quasar 3c 273, Bernd Husemann, Vardha Nicola Bennert, Knud Jahnke, Timothy A. Davis, Jong-Hak Woo, Julia Scharwächter, Andreas Schulze, Massimo Gaspari, Martin A. Zwaan

Physics

We present an unprecedented view of the morphology and kinematics of the extended narrow-line region (ENLR) and molecular gas around the prototypical hyperluminous quasar 3C 273 (L bol ~ 1047 erg s−1 at z = 0.158) based on VLT-MUSE optical 3D spectroscopy and ALMA observations. We find the following: (1) the ENLR size of 12.1 ± 0.2 kpc implies a smooth continuation of the size–luminosity relation out to large radii or a much larger break radius as previously proposed. (2) The kinematically disturbed ionized gas with line splits reaching 1000 km s−1 out to 6.1 ...


Brightest Cluster Galaxy Evolution Exploration: Comparing The Separation Of Cluster X-Ray Light And Visible Wavelength Galaxy Light With Spectral Data, Matthew Aaron Salinas Jul 2019

Brightest Cluster Galaxy Evolution Exploration: Comparing The Separation Of Cluster X-Ray Light And Visible Wavelength Galaxy Light With Spectral Data, Matthew Aaron Salinas

Physics

Brightest Cluster Galaxies (BCGs), the brightest galaxy in a cluster of hundreds to thousands of galaxies, are some of the biggest, brightest, and most massive galaxies in the universe. Characterizing a BCG can help discover more about galaxy evolution - the aging, changing, and possible merging (collisions) of galaxies. This project involves determining the separation of the peak of x-ray emission of the galaxy cluster, and the peak of visible emission of the BCG to characterize the system as being disturbed or undisturbed that can then lead to discoveries about its formation and evolution. We have found that 17.4% of ...


Lasers, Noah B. Caro Jun 2019

Lasers, Noah B. Caro

Physics

No abstract provided.