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Full-Text Articles in Physical Sciences and Mathematics

Development Of A Humidity-Resistant Coating To Impart High Oxygen Barrier Performance To Food Packaging Films, Ryan Yinghua Cox Jun 2017

Development Of A Humidity-Resistant Coating To Impart High Oxygen Barrier Performance To Food Packaging Films, Ryan Yinghua Cox

Master's Theses

Oxygen barrier coatings have the potential to greatly extend the lifetime of certain food products by incorporating them into existing food packaging. Present technologies face definite challenges of maintaining high performance, while attaining simple and inexpensive preparation methods. The oxygen barrier effect obtained with these coatings is also susceptible to a plasticization effect when exposed to high humidity, since water vapor molecules are readily soluble in typically hydrophilic resins. In this work, we demonstrate a 1 – 2 micron thick oxygen barrier coating, prepared on a 12 micron poly(ethylene terephthalate) substrate, that has oxygen transmission rates as low as 1.44 …


Paper Microzone Plates As Analytical Tools For Studying Enzyme Stability: A Case Study On The Stabilization Of Horseradish Peroxidase Using Trehalose And Su-8 Epoxy Novolac Resin, Kirsten A. Ganaja, Cory Chaplan, Jingyi Zhang, Nathaniel W. Martinez, Andres W. Martinez May 2017

Paper Microzone Plates As Analytical Tools For Studying Enzyme Stability: A Case Study On The Stabilization Of Horseradish Peroxidase Using Trehalose And Su-8 Epoxy Novolac Resin, Kirsten A. Ganaja, Cory Chaplan, Jingyi Zhang, Nathaniel W. Martinez, Andres W. Martinez

Chemistry and Biochemistry

Paper microzone plates in combination with a noncontact liquid handling robot were demonstrated as tools for studying the stability of enzymes stored on paper. The effect of trehalose and SU-8 epoxy novolac resin (SU-8) on the stability of horseradish peroxidase (HRP) was studied in both a short-term experiment, where the activity of various concentrations of HRP dried on paper were measured after 1 h, and a long-term experiment, where the activity of a single concentration of HRP dried and stored on paper was monitored for 61 days. SU-8 was found to stabilize HRP up to 35 times more than trehalose …


Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde May 2017

Soil Science Lesson Plan For The Cal Poly Learn By Doing Lab, Kelsey Ormonde

Natural Resources Management and Environmental Sciences

To increase interest in soil science and other related sciences, educational materials need to be tailored to appeal to younger students. The purpose of this project was to create a soil science lesson plan that could be utilized by the Cal Poly Learn By Doing Lab. Information from several articles, textbooks, lesson plans, and websites was reviewed to create a soil science lesson plan for students in 5-8th grade. The lesson plan focused on the three sub-disciplines of soil science; physical, chemical, and biological. Activities were created to correspond to the three sub-disciplines. Alternate activities were created to allow …


Discovery And Follow-Up Observations Of The Young Type Ia Supernova 2016coj, Weikang Zheng, Alexei V. Filippenko, Jon Mauerhan, Melissa L. Graham, Vardha Nicola Bennert, Xiaofeng Wang May 2017

Discovery And Follow-Up Observations Of The Young Type Ia Supernova 2016coj, Weikang Zheng, Alexei V. Filippenko, Jon Mauerhan, Melissa L. Graham, Vardha Nicola Bennert, Xiaofeng Wang

Physics

The Type Ia supernova (SN Ia) 2016coj in NGC 4125 (redshift z = 0.00452 ± 0.00006) was discovered by the Lick Observatory Supernova Search 4.9 days after the fitted first-light time (FFLT; 11.1 days before B-band maximum). Our first detection (prediscovery) is merely 0.6 ± 0.5 days after the FFLT, making SN 2016coj one of the earliest known detections of an SN Ia. A spectrum was taken only 3.7 hr after discovery (5.0 days after the FFLT) and classified as a normal SN Ia. We performed high-quality photometry, low- and high-resolution spectroscopy, and spectropolarimetry, finding that SN 2016coj is …


Development, Implementation, And Validation Of A California Coastal Ocean Modeling, Data Assimilation, And Forecasting System, Yi Chao, John D. Farrara, Hongchun Zhang, Kevin Armenta, Luca Centurioni, Francisco Chavez, James B. Girton, Dan Rudnick, Ryan K. Walter Apr 2017

Development, Implementation, And Validation Of A California Coastal Ocean Modeling, Data Assimilation, And Forecasting System, Yi Chao, John D. Farrara, Hongchun Zhang, Kevin Armenta, Luca Centurioni, Francisco Chavez, James B. Girton, Dan Rudnick, Ryan K. Walter

Physics

A three-dimensional, near real-time data-assimilative modeling system for the California coastal ocean is presented. The system consists of a Regional Ocean Modeling System (ROMS) forced by the North American Mesoscale Forecast System (NAM). The ocean model has a horizontal resolution of approximately three kilometers and utilizes a multi-scale three-dimensional variational (3DVAR) data assimilation methodology. The system is run in near real-time to produce a nowcast every six hours and a 72-hour forecast every day. The performance of this nowcast system is presented using results from a six-year period of 2009–2015.

The ROMS results are first compared with the assimilated data …


Group Work Versus Informal Collaborations: Student Perspectives, Andrew Danowitz Apr 2017

Group Work Versus Informal Collaborations: Student Perspectives, Andrew Danowitz

Computer Science and Software Engineering

A substantial body of research exists showing that, when implemented correctly, the use of group work in a class can improve student learning outcomes. When implemented incorrectly, however, group-based assignments can lead to dysfunction and inter-personal conflicts that can hamper overall student success. This problem can be especially acute in first and second year engineering fundamentals courses where advanced students who learn the concepts faster may end up completing—and reaping the benefits of—a lions-share of the group work. As the course material starts to build on itself, those students who initially underperformed in their group may lack the understanding to …


Extending The Calibration Of C Iv-Based Single-Epoch Black Hole Mass Estimators For Active Galactic Nuclei, Daeseong Park, Aaron J. Barth, Jong-Hak Woo, Matthew A. Malkan, Tommaso Treu, Vardha Nicola Bennert, Roberto J. Assef, Anna Pancoast Apr 2017

Extending The Calibration Of C Iv-Based Single-Epoch Black Hole Mass Estimators For Active Galactic Nuclei, Daeseong Park, Aaron J. Barth, Jong-Hak Woo, Matthew A. Malkan, Tommaso Treu, Vardha Nicola Bennert, Roberto J. Assef, Anna Pancoast

Physics

We provide an updated calibration of C iv broad emission line–based single-epoch (SE) black hole (BH) mass estimators for active galactic nuclei (AGNs) using new data for six reverberation-mapped AGNs at redshift with BH masses (bolometric luminosities) in the range ( erg s−1). New rest-frame UV-to-optical spectra covering 1150–5700 Å for the six AGNs were obtained with the Hubble Space Telescope (HST). Multicomponent spectral decompositions of the HST spectra were used to measure SE emission-line widths for the C iv, Mg ii, and Hβ lines, as well as continuum luminosities in the spectral region around each line. …


Probabilistic Roadmaps For Virtual Camera Pathing With Cinematographic Principles, Katherine Davis Apr 2017

Probabilistic Roadmaps For Virtual Camera Pathing With Cinematographic Principles, Katherine Davis

Master's Theses

As technology use increases in the world and inundates everyday life, the visual aspect of technology or computer graphics becomes increasingly important. This thesis presents a system for the automatic generation of virtual camera paths for fly-throughs of a digital scene. The sample scene used in this work is an underwater setting featuring a shipwreck model with other virtual underwater elements such as rocks, bubbles and caustics. The digital shipwreck model was reconstructed from an actual World War II shipwreck, resting off the coast of Malta. Video and sonar scans from an autonomous underwater vehicle were used in a photogrammetry …


Iota Pi Application For Ios, Deborah Newberry Mar 2017

Iota Pi Application For Ios, Deborah Newberry

Computer Science and Software Engineering

Kappa Kappa Psi is a national honorary fraternity for college band members. They meet every Sunday night, and during these meetings they plan events (both internal and external) that aim to meet our goal of making sure that the Cal Poly band programs have their social, financial, material, and educational needs satisfied. This paper details the steps I took to create an application for them to use internally to help ease organizational processes.


Music Times: A Music Learning Game, Emily Woo Mar 2017

Music Times: A Music Learning Game, Emily Woo

Computer Science and Software Engineering

Music Times is a two dimensional educational video game with the purpose of gamifying learning of musical concepts. It has elements of adventure and visual novel games, and incentivizes the player to learn music to explore new levels. It is developed in the Unity game engine, scripted in C#, and targeted for mobile devices. It has six working levels: three lesson levels and three corresponding challenge levels. Each level contains slight differences in visual and aural feel.


Stream Terrace Genesis Along Bunte Creek In The Elkhorn Plain, Ca, Madi Allgaier, Shelley Anderson, Duncan Lord Mar 2017

Stream Terrace Genesis Along Bunte Creek In The Elkhorn Plain, Ca, Madi Allgaier, Shelley Anderson, Duncan Lord

Natural Resources Management and Environmental Sciences

There are several factors influencing terrace genesis and terrace types in Bunte Creek. Strath terraces exist at upper Bunte Creek, whereas thick fill terraces exist at lower Bunte Creek. Analysis of these terraces leads to insight on what specific factors lead to their formation. Terraces were mapped along the extent of Bunte Creek. Sediment data and terrace-height data were collected for in order to make a complete analysis of the terraces. Tectonic uplift led to incision and strath terrace genesis at upper Bunte Creek. Climatic forcing and base-level rise caused alluvial aggradation behind a shutter ridge that intersects lower Bunte …


Space Telescope And Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign And Emission-Line Analysis For Ngc 5548, L. Pei, M. M. Fausnaugh, A. J. Barth, B. M. Peterson, Vardha Nicola Bennert, Y. Zu Mar 2017

Space Telescope And Optical Reverberation Mapping Project. V. Optical Spectroscopic Campaign And Emission-Line Analysis For Ngc 5548, L. Pei, M. M. Fausnaugh, A. J. Barth, B. M. Peterson, Vardha Nicola Bennert, Y. Zu

Physics

We present the results of an optical spectroscopic monitoring program targeting NGC 5548 as part of a larger multiwavelength reverberation mapping campaign. The campaign spanned 6 months and achieved an almost daily cadence with observations from five ground-based telescopes. The Hβ and He ii λ4686 broad emission-line light curves lag that of the 5100 Å optical continuum by and , respectively. The Hβ lag relative to the 1158 Å ultraviolet continuum light curve measured by the Hubble Space Telescope is ~50% longer than that measured against the optical continuum, and the lag difference is consistent with the …


Hitchride Ios App, Petar Georgiev Mar 2017

Hitchride Ios App, Petar Georgiev

Computer Science and Software Engineering

HitchRide is a ride-sharing marketplace connecting regular people making similar trips so everyone benefits: the driver, the passenger, society and the environment. HitchRide allows participants to reduce their travel costs, meet new friends and conveniently reach their destination, all in a simple, satisfactory, and environmentally friendly way. We believe that we can make traveling truly enjoyable, one shared car ride at a time and help save the planet while we’re at it!


Using Intel Realsense Depth Data For Hand Tracking In Unreal Engine 4, Granger Lang Mar 2017

Using Intel Realsense Depth Data For Hand Tracking In Unreal Engine 4, Granger Lang

Liberal Arts and Engineering Studies

This project describes how to build a hand tracking method for VR/AR using the raw data from a depth sensing camera.


Gpumap: A Transparently Gpu-Accelerated Map Function, Ivan Pachev Mar 2017

Gpumap: A Transparently Gpu-Accelerated Map Function, Ivan Pachev

Master's Theses

As GPGPU computing becomes more popular, it will be used to tackle a wider range of problems. However, due to the current state of GPGPU programming, programmers are typically required to be familiar with the architecture of the GPU in order to effectively program it. Fortunately, there are software packages that attempt to simplify GPGPU programming in higher-level languages such as Java and Python. However, these software packages do not attempt to abstract the GPU-acceleration process completely. Instead, they require programmers to be somewhat familiar with the traditional GPGPU programming model which involves some understanding of GPU threads and kernels. …


Developing An Imaging System To Monitor Atom Traps For Neutral Atom Quantum Computing, Jenna Valdez Mar 2017

Developing An Imaging System To Monitor Atom Traps For Neutral Atom Quantum Computing, Jenna Valdez

Physics

Quantum computing exploits the laws of quantum mechanics to exponentially increase computing rate for certain processes. A realized quantum computer could break encryptions and simulate large quantum systems previously unbreakable and unattainable with classical computers. Neutral atom quantum computing is a viable candidate for building these devices that satisfies four of the five criteria for a successful quantum computer. We are exploring a novel method in creating neutral atom qubits that involves a magneto-optical trap and a dipole trap created in the diffraction pattern behind an array of pinholes. The magneto-optical trap works to cool the atoms and centralize them …


Thermal Evolution Of Moon, Arshdeep Singh Gill Mar 2017

Thermal Evolution Of Moon, Arshdeep Singh Gill

Master's Theses

In August, 2014 three experiments were conducted using infrared systems deployed at White Mountain Research center, CA. The data was acquired for the whole month of August. Teams of 3-4 students from Cal Poly San Luis Obispo and UC Santa Barbara were stationed at the research center for 2-3 days to operate the equipment. The three experiments were:(1) creating spatial-temporal time series of lunar surface temperatures;(2) identifying atmospheric meteor trails;(3) search for meteor impacts on the Moon surface. Out of the three this thesis focusses on experiment 1 and the results from this experiment could also help with the other …


Fading Agn Candidates: Agn Histories And Outflow Signatures, William C. Keel, Chris J. Lintott, W. Peter Maksym, Vardha N. Bennert, S. Drew Chojnowski, Alexei Moiseev, Aleksandrina Smirnova, Kevin Schawinski, Lia F. Sartori, C. Megan Urry, Anna Pancoast, Mischa Schirmer, Bryan Scott, Charles Grant Showley, Kelsi Flatland Feb 2017

Fading Agn Candidates: Agn Histories And Outflow Signatures, William C. Keel, Chris J. Lintott, W. Peter Maksym, Vardha N. Bennert, S. Drew Chojnowski, Alexei Moiseev, Aleksandrina Smirnova, Kevin Schawinski, Lia F. Sartori, C. Megan Urry, Anna Pancoast, Mischa Schirmer, Bryan Scott, Charles Grant Showley, Kelsi Flatland

Physics

We consider the energy budgets and radiative history of eight fading active galactic nuclei (AGNs), identified from an energy shortfall between the requirements to ionize very extended (radius > 10 kpc) ionized clouds and the luminosity of the nucleus as we view it directly. All show evidence of significant fading on timescales of ≈50,000 yr. We explore the use of minimum ionizing luminosity Qion derived from photoionization balance in the brightest pixels in Hα at each projected radius. Tests using presumably constant Palomar–Green QSOs, and one of our targets with detailed photoionization modeling, suggest that we can derive useful …


Implementing Semantic Document Search Using A Bounded Random Walk In A Probabilistic Graph, Lubomir Stanchev Jan 2017

Implementing Semantic Document Search Using A Bounded Random Walk In A Probabilistic Graph, Lubomir Stanchev

Computer Science and Software Engineering

Given a set of documents and an input query that is expressed using natural language, the problem of document search is retrieving all relevant documents ordered by the degree of relevance. Semantic document search fetches not only documents that contain words from the input query, but also documents that are semantically relevant. For example, the query "friendly pets" will consider documents that contain the words "dog" and "cat", among others. One way to implement semantic search is to use a probabilistic graph in which the input query is connected to the documents through paths that contain semantically similar words and …


Local Diurnal Wind‐Driven Variability And Upwelling In A Small Coastal Embayment, Ryan K. Walter, Emma C. Reid, Kristen A. Davis, Kevin Armenta, Kevin Merhoff, Nicholas J. Nidzieko Jan 2017

Local Diurnal Wind‐Driven Variability And Upwelling In A Small Coastal Embayment, Ryan K. Walter, Emma C. Reid, Kristen A. Davis, Kevin Armenta, Kevin Merhoff, Nicholas J. Nidzieko

Physics

The oceanic response to high‐frequency local diurnal wind forcing is examined in a small coastal embayment located along an understudied stretch of the central California coast. We show that local diurnal wind forcing is the dominant control on nearshore temperature variability and circulation patterns. A complex empirical orthogonal function (CEOF) analysis of velocities in San Luis Obispo Bay reveals that the first‐mode CEOF amplitude time series, which accounts for 47.9% of the variance, is significantly coherent with the local wind signal at the diurnal frequency and aligns with periods of weak and strong wind forcing. The diurnal evolution of the …


Paper-Based Diagnostic Devices, Spencer A. Schultz, Isabelle C. Noxon, Tyler A. Sisley, Andres W. Martinez Jan 2017

Paper-Based Diagnostic Devices, Spencer A. Schultz, Isabelle C. Noxon, Tyler A. Sisley, Andres W. Martinez

Chemistry and Biochemistry

This chapter will provide an overview of existing diagnostic devices made primarily out of paper and then focus on paper-based microfluidic devices, the next generation of paper-based diagnostic devices that promises to extend the use of paper as a material for fabricating diagnostic devices well into the future.

Chapter Contents:

  • 2.1 Introduction
  • 2.2 Current paper-based diagnostic devices
  • 2.2.1 Dipstick devices
  • 2.2.2 Lateral-flow devices
  • 2.2.2.1 Vertical-flow devices
  • 2.2.3 Paper-based arrays
  • 2.3 Paper-based microfluidic devices
  • 2.3.1 Fabrication of paper-based microfluidic devices
  • 2.3.2 Applications of paper-based microfluidic devices
  • 2.4 Conclusions
  • References


Effects Of Habitat Restoration On Soil Retention On Santa Rosa Island, Michael Perez, Kathryn Mceachern, Ken Niessen Jan 2017

Effects Of Habitat Restoration On Soil Retention On Santa Rosa Island, Michael Perez, Kathryn Mceachern, Ken Niessen

STAR Program Research Presentations

Ranching began on Santa Rosa Island in the 1840’s, consequently introducing nonnative megafauna that put novel selective grazing pressures on endemic plant species. Their movement patterns also altered substrate integrity as the land became denuded of any stabilizing vegetation. Dense groves of island oak (Q. tomentella) are known to aid in sediment deposition and retention. The groves also function to collect water during periods of intense fog common to the island. This experiment sought to determine whether sediment is being lost or deposited on a ridge in the middle of the island containing a grove of Q. tomentella …


Phthalate Plasticizers Covalently Linked To Pvc Via Copper-Free Or Copper Catalyzed Axide-Alkyne Cycloadditions, Aruna Earla, Li Longbo, Philip Costanzo, Rebecca Braslau Dec 2016

Phthalate Plasticizers Covalently Linked To Pvc Via Copper-Free Or Copper Catalyzed Axide-Alkyne Cycloadditions, Aruna Earla, Li Longbo, Philip Costanzo, Rebecca Braslau

Chemistry and Biochemistry

Plasticization of PVC was carried out by covalently linking phthalate derivatives via copper-free (thermal) or copper catalyzed azide-alkyne cycloadditions. Di(2-ethylhexyl) phthalate derivatives (DEHP-ether and DEHP-ester) were synthesized and appended to PVC at two different densities. The glass transition temperatures of the modified PVC decreased with increasing content of plasticizer. PVC-DEHP-ether gave lower glass transition temperatures than PVC-DEHP-ester, reflecting the enhanced flexibility of the ether versus ester linker.


An Examination Of Student Outcomes In Studio Chemistry, Alan L. Kiste, Gregory E. Scott, Jesse Paul Bukenberger, Miles Markmann, Jennifer Moore Dec 2016

An Examination Of Student Outcomes In Studio Chemistry, Alan L. Kiste, Gregory E. Scott, Jesse Paul Bukenberger, Miles Markmann, Jennifer Moore

Chemistry and Biochemistry

Twenty years ago, a major curriculum revision at a large, comprehensive university in the Western United States led to the implementation of an integrated lecture/laboratory (studio) experience for our engineering students taking general chemistry. Based on these twenty years of experience, construction of four purpose-built studio classrooms to house the majority of the remaining general chemistry courses was completed in 2013. A detailed study of the effects of the entire ecology of the studio experience on student success was initiated at that time. Data from content knowledge pre- and post-tests, learning attitudes surveys, and student course evaluations show positive effects …


Android Drone: Remote Quadcopter Control With A Phone, Aubrey John Russell Dec 2016

Android Drone: Remote Quadcopter Control With A Phone, Aubrey John Russell

Computer Engineering

The purpose of the “Android Drone” project was to create a quadcopter that can be controlled by user input sent over the phone’s Wi-Fi connection or 4G internet connection. Furthermore, the purpose was also to be able to receive live video feedback over the internet connection, thus making the drone an inexpensive option compared to other, equivalent drones that might cost thousands of dollars. Not only that, but the Android phone also has a host of other useful features that could be utilized by the drone: this includes GPS, pathing, picture taking, data storage, networking and TCP/IP, a Java software …


Implementation And Testing Of A Book Lookup System For The Robert E. Kennedy Library, Casey C. Sheehan Dec 2016

Implementation And Testing Of A Book Lookup System For The Robert E. Kennedy Library, Casey C. Sheehan

Computer Science and Software Engineering

The goal of this senior project centered around improving the quality of student and teacher experiences when visiting the library. The task of finding a book amongst the shelves is an arduous one, which I felt could be improved upon through implementation and testing of a Book Lookup system for the Cal Poly Robert E. Kennedy Library. Development for this project was done using a Python framework. Testing and earlier designs were also created using JavaScript and PHP. Repeated tests were conducted on the accuracy of the software and its ability to decrease user search-time when compared to conventional methods.


Review Classification, Balraj Aujla Dec 2016

Review Classification, Balraj Aujla

Computer Science and Software Engineering

The goal of this project is to find a way to analyze reviews and determine the sentiment of a review. It uses various machine learning techniques in order to achieve its goals such as SVMs and Naive Bayes. Overall the purpose is to learn many different machine learning techniques, determine which ones would be useful for the project, then compare the results. Research is the foremost goal of the project, and it is able to determine the better algorithm for review classification, naive bayes or an SVM. In addition, an SVM which actually gave review’s scores rather than just classifying …


Ios Application For Inventory In Small Retail Stores, Andrea Savage Dec 2016

Ios Application For Inventory In Small Retail Stores, Andrea Savage

Computer Science and Software Engineering

Currently, small retail stores with low technology budgets such as those right here in San Luis Obispo are struggling to integrate new technologies into their companies. This mobile application built for iOS with a Firebase backend is seeking to remove their barriers to entry. I built this application to give small retail stores a customizable application that allows them to display products electronically to customers and maintain accurate inventory both in one place. The construction of this application hinged around three major design decisions: UI design of the color management views, organization of the database, and accessing the database with …


Fine-Tuning An Algorithm For Semantic Document Clustering Using A Similarity Graph, Lubomir Stanchev Dec 2016

Fine-Tuning An Algorithm For Semantic Document Clustering Using A Similarity Graph, Lubomir Stanchev

Computer Science and Software Engineering

In this article, we examine an algorithm for document clustering using a similarity graph. The graph stores words and common phrases from the English language as nodes and it can be used to compute the degree of semantic similarity between any two phrases. One application of the similarity graph is semantic document clustering, that is, grouping documents based on the meaning of the words in them. Since our algorithm for semantic document clustering relies on multiple parameters, we examine how fine-tuning these values affects the quality of the result. Specifically, we use the Reuters-21578 benchmark, which contains 11,362 newswire stories …


Compounding Fire Disturbance History Encourages Coast Redwood (Sequoia Sempervirens) Regeneration And Community Dominance, Matthew R. Brousil Dec 2016

Compounding Fire Disturbance History Encourages Coast Redwood (Sequoia Sempervirens) Regeneration And Community Dominance, Matthew R. Brousil

Master's Theses

Disturbance is fundamental to forest ecosystem function and overall health, but climate change is likely to increase both disturbance frequency and intensity in the future. Forests subject to increasingly frequent and intense disturbances are more likely to experience compounding disturbance effects. Compounding disturbances may exert unpredicted, non-additive stresses on ecosystems, leading to novel conditions that may exceed the capacity for local species to survive and regenerate. I further hypothesize that compounding disturbances could create conditions misaligned with species’ adaptations by altering physical and chemical growing conditions in forest soils, affecting forest composition, structure, and, subsequently, function for many years following …