Physical Sciences and Mathematics Commons^™

Initial Implementation Of A Machine Learning System For Srf Cavity Fault Classification At Cebaf, A. Carpenter, K. M. Iftekharuddin, T. Powers, Y. Roblin, A. Solopava Shabalina, C. Tennant, L. Vidyaratne

Electrical & Computer Engineering Faculty Publications

The Continuous Electron Beam Accelerator Facility (CEBAF) at Jefferson Laboratory is a high power Continuous Wave (CW) electron accelerator. It uses a mixture of of SRF cryomodules: older, lower energy C20/C50 modules and newer, higher energy C100 modules. The cryomodules are arrayed in two anti-parallel linear accelerators. Accurately classifying the type of cavity faults is essential to maintaining and improving accelerator performance. Each C100 cryomodule contains eight 7-cell cavities. When a cavity fault occurs within a cryomodule, all eight cavities generate 17 waveforms each containing 8192 points. This data is exported from the control system and saved for review. Analysis …

A Review: Thermal Stability Of Methylammonium Lead Halide Based Perovskite Solar Cells, Tanzila Tasnim Ava, Abdullah Al Mamun, Sylvain Marsillac, Gon Namkoong

Electrical & Computer Engineering Faculty Publications

Perovskite solar cells have achieved photo-conversion efficiencies greater than 20%, making them a promising candidate as an emerging solar cell technology. While perovskite solar cells are expected to eventually compete with existing silicon-based solar cells on the market, their long-term stability has become a major bottleneck. In particular, perovskite films are found to be very sensitive to external factors such as air, UV light, light soaking, thermal stress and others. Among these stressors, light, oxygen and moisture-induced degradation can be slowed by integrating barrier or interface layers within the device architecture. However, the most representative perovskite absorber material, CH_{3 …}

The Effect Of Tube Geometry On The Chiral Plasma, S. Jin, D. Zou, X. Lu, Mounir Laroussi

Electrical & Computer Engineering Faculty Publications

A chiral plasma plume has recently been reported inside a circular quartz tube without the use of an external magnetic field. It is believed that the quartz tube plays an important role in the formation of the chiral plasma plume. In this paper, to better understand how this interesting structure is generated, the effect of the tube geometry on the chiral plasma is investigated. First, the effect of the thickness of the tube wall on the chiral plasma is investigated. It is interesting to find that a too thin or too thick tube wall is not favorable for generating the …

Carbon Multicharged Ion Generation From Laser-Spark Ion Source, Md. Mahmudur Rahman, Oguzhan Balki, Hani E. Elsayed-Ali

Electrical & Computer Engineering Faculty Publications

Multicharged carbon ions are generated by using a laser-assisted spark-discharge ion source. A Q-switched Nd:YAG laser pulse (1064 nm, 7 ns, ≤ 4.5 × 10⁹ W/cm²) focused onto the surface of a glassy carbon target results in its ablation. The spark-discharge (∼1.2 J energy, ∼1 µs duration) is initiated along the direction of the plume propagation between the target surface and a grounded mesh that is parallel to the target surface. Ions emitted from the laser-spark plasma are detected by their time-of-flight using a Faraday cup. The ion energy-to-charge ratio is analyzed by a three-mesh retarding field …

End-To-End Learning Via A Convolutional Neural Network For Cancer Cell Line Classification, Darlington A. Akogo, Xavier-Lewis Palmer

Electrical & Computer Engineering Faculty Publications

Purpose: Computer vision for automated analysis of cells and tissues usually include extracting features from images before analyzing such features via various machine learning and machine vision algorithms. The purpose of this work is to explore and demonstrate the ability of a Convolutional Neural Network (CNN) to classify cells pictured via brightfield microscopy without the need of any feature extraction, using a minimum of images, improving work-flows that involve cancer cell identification.

Design/methodology/approach: The methodology involved a quantitative measure of the performance of a Convolutional Neural Network in distinguishing between two cancer lines. In their approach, they trained, validated and …

Detecting Special-Cause Variation 'Events' From Process Data Signatures, Timothy M. Young, Olga Khaliukova, Nicolas André, Alexander Petutschnigg, Timothy G. Rials, Chung-Hao Chen

Electrical & Computer Engineering Faculty Publications

The ability to detect the special-cause variation of incoming feedstocks from advanced sensor technology is invaluable to manufacturers. Many on-line sensors produce data signatures that require further off-line statistical processing for interpretation by operational personnel. However, early detection of changes in variation in incoming feedstocks may be imperative to promote early-stage preventive measures. A method is proposed in this applied study for developing control bands to quantify the variation of data signatures in the context of statistical process control (SPC). Control bands based on pointwise prediction intervals constructed from the Bonferroni Inequality and Bayesian smoothing splines are developed. Applications using …

How Ceo Wealth Affects The Riskiness Of A Firm, Sonik Mandal, Charlie Swartz, Sanjib Guha, Carl B. Mcgowan Jr.

Finance Faculty Publications

The objective of this paper is to analyze the relationship between the ownership level of managers and the risk averse behavior of the firm. We measure the ownership level of the managers by the ratio of their ownership of the company relative to their total wealth for a sample of 69 individuals from the Forbes 400 list of the wealthiest individuals in the world for the period from 2001-11 using an unbalanced panel data analysis. The dependent variable is the Altman Z-score of each firm and we further test these relationships using financial leverage. The independent variables are delta and …

Classification Of Aerosol Population Type And Cloud Condensation Nuclei Properties In A Coastal California Littoral Environment Using An Unsupervised Cluster Model, Samuel A. Atwood, Sonia M. Kreidenweis, Paul J. Demott, Markus D. Petters, Gavin Cornwell, Andrew C. Martin, Kathryn A. Moore

Geography Faculty Publications and Presentations

Aerosol particle and cloud condensation nuclei (CCN) measurements from a littoral location on the northern coast of California at Bodega Bay Marine Laboratory (BML) are presented for approximately six weeks of observations during the boreal winter–spring as part of the CalWater-2015 field campaign. The nature and variability of surface (marine boundary layer, MBL) aerosol populations were evaluated by classifying observations into periods of similar aerosol and meteorological characteristics using an unsupervised cluster model to derive distinct littoral aerosol population types and link them to source regions. Such classifications support efforts to understand the impact of changing aerosol properties on precipitation …

A Recent Systematic Increase In Vapor Pressure Deficit Over Tropical South America, Armineh Barkhordarian, Bahareh Saatchi, Ali Behrangi, Paul C. Loikith, Carlos R. Mechoso

Geography Faculty Publications and Presentations

We show a recent increasing trend in Vapor Pressure Deficit (VPD) over tropical South America in dry months with values well beyond the range of trends due to natural variability of the climate system defined in both the undisturbed Preindustrial climate and the climate over 850–1850 perturbed with natural external forcing. This trend is systematic in the southeast Amazon but driven by episodic droughts (2005, 2010, 2015) in the northwest, with the highest recoded VPD since 1979 for the 2015 drought. The univariant detection analysis shows that the observed increase in VPD cannot be explained by greenhouse-gas-induced (GHG) radiative warming …

Optimaztion Of Fantasy Basketball Lineups Via Machine Learning, James Earl

Senior Honors Theses

Machine learning is providing a way to glean never before known insights from the data that gets recorded every day. This paper examines the application of machine learning to the novel field of Daily Fantasy Basketball. The particularities of the fantasy basketball ruleset and playstyle are discussed, and then the results of a data science case study are reviewed. The data set consists of player performance statistics as well as Fantasy Points, implied team total, DvP, and player status. The end goal is to evaluate how accurately the computer can predict a player’s fantasy performance based off a chosen feature …

Enrollment And Assessment Of A First-Year College Class Social Network For A Controlled Trial Of The Indirect Effect Of A Brief Motivational Intervention, Nancy P. Barnett, Melissa A. Clark, Shannon R. Kenney, Graham Diguiseppi, Matthew K. Meisel, Sara Balestrieri, Miles Q. Ott, John Light

Statistical and Data Sciences: Faculty Publications

Heavy drinking and its consequences among college students represent a serious public health problem, and peer social networks are a robust predictor of drinking-related risk behaviors. In a recent trial, we administered a Brief Motivational Intervention (BMI) to a small number of first-year college students to assess the indirect effects of the intervention on peers not receiving the intervention. Objectives: To present the research design, describe the methods used to successfully enroll a high proportion of a first-year college class network, and document participant characteristics. Methods: Prior to study enrollment, we consulted with a student advisory group and campus stakeholders …

An Introduction To The 'Oceans And Society: Blue Planet' Initiative, Emily A. Smail, Paul M. Digiacomo, Sophie Seeyave, Samy Djavidnia, Louis Celliers, Pierre-Yves Le Traon, Jeremy Gault, Elva Escobar-Briones, Hans-Peter Plag, Christine Pequignet, Lenore Bajona, Li Zhang, Jay Pearlman, Andy Steven, Jonathan Hodge, Marie-Fanny Racault, Curt Storlazzi, William Skirving, Ron Hoeke, John Marra, Ap Van Dongeren, Frank Muller-Karger, Douglas Cripe, Daniel Takaki

OES Faculty Publications

We live on a blue planet, and Earth’s waters benefit many sectors of society. The future of our blue planet is increasingly reliant on the services delivered by marine, coastal and inland waters and on the advancement of effective, evidence-based decisions on sustainable development. ‘Oceans and Society: Blue Planet’ is an initiative of the Group on Earth Observations (GEO) that aims to ensure the sustained development and use of ocean and coastal observations for the benefit of society. The initiative works to advance and exploit synergies among the many observational programmes devoted to ocean and coastal waters; to improve engagement …

Metagenomic Sequencing Identifies Highly Diverse Assemblages Of Dinoflagellate Cysts In Sediments From Ships' Ballast Tanks, Lixia Shang, Zhangxi Hu, Yunyan Deng, Yuyang Liu, Xinyu Zhai, Zhaoyang Chai, Xiaohan Liu, Zifeng Zhan, Fred C. Dobbs, Ying Zhong Tang

OES Faculty Publications

Ships' ballast tanks have long been known as vectors for the introduction of organisms. We applied next-generation sequencing to detect dinoflagellates (mainly as cysts) in 32 ballast tank sediments collected during 2001-2003 from ships entering the Great Lakes or Chesapeake Bay and subsequently archived. Seventy-three dinoflagellates were fully identified to species level by this metagenomic approach and single-cell polymerase chain reaction (PCR)-based sequencing, including 19 toxic species, 36 harmful algal bloom (HAB) forming species, 22 previously unreported as producing cysts, and 55 reported from ballast tank sediments for the first time (including 13 freshwater species), plus 545 operational taxonomic units …

Dinitrogen Fixation Across Physico-Chemical Gradients Of The Eastern Tropical North Pacific Oxygen Deficient Zone, C. R. Selden, M. R. Mulholland, P.W. Bernhardt, B. Widner, A. Macías-Tapia, Q. Ji, A. Jayakumar

OES Faculty Publications

The Eastern Tropical North Pacific Ocean hosts one of the world's largest oceanic oxygen deficient zones (ODZs). Hot spots for reactive nitrogen (N_r) removal processes, ODZs generate conditions proposed to promote N_r inputs via dinitrogen (N₂) fixation. In this study, we quantified N₂ fixation rates by ¹⁵N tracer bioassay across oxygen, nutrient, and light gradients within and adjacent to the ODZ. Within subeuphotic oxygen‐deplete waters, N₂ fixation was largely undetectable; however, addition of dissolved organic carbon stimulated N₂ fixation in suboxic (μmol/kg O₂) waters, suggesting that diazotroph communities are …

The Role Of Data Analytics In Education: Possibilities & Limitations, Robert L. Moore

STEMPS Faculty Publications

In the last decade, we have seen dramatic increases in the integration of technology within education. It has now become commonplace for K-5 educators to apply learning management systems (LMS) in ways that were previously only seen in higher education contexts. Similarly, on the higher education side, we are seeing a significant increase in online learning evidenced by the growing number of for-profit online colleges and universities (Picciano, 2012). This chapter utilizes Khan’s Learning Framework (Khan, 2001, 2005) to explore the role data analytics can play in education by looking at the possibilities and limitations of analytics.

Ecosystem Processes, Land Cover, Climate, And Human Settlement Shape Dynamic Distributions For Golden Eagle Across The Western Us, J.D. Tack, B.R. Noon, Z.H. Bowen, B.C. Fedy

United States Geological Survey: Staff Publications

Species–environment relationships for highly mobile species outside of the breeding season are often highly dynamic in response to the collective effects of everchanging climatic conditions, food resources, and anthropogenic disturbance. Capturing dynamic space-use patterns in a model-based framework is critical as model inference often drives place-based conservation planning. We applied dynamic occupancy models to broad-scale golden eagle Aquila chrysaetos survey data collected annually from 2006 to 2012 during the late summer post-fledging period in the western US. We defined survey sites as 10 km transect segments with a 1 km buffer on either transect side (n = 3540). Derived estimates …

Gamma Radiation And Neutron Shielding Properties Of Transparent Alkali Borosilicate Glass Containing Lead, Elsayed Salama, Abeer Maher, Gamal Youssef

Basic Science Engineering

In this study, lithium sodium borosilicate glasses with chemical compositions of xPbO-40B₂O₃25Na₂O5Li₂O-(30 - x)SiO₂ (where x = 0, 5, 10, 15, 20, and 25 mol%) were prepared by using the conventional melt-quenching technique. The amorphous nature and the effects of Pb+2 ions in the glass structure were explored by using X-ray diffraction and Fourier transform infrared spectroscopy analyses, respectively. The gamma radiation and neutron shielding properties of the glass system were investigated by determining the mass attenuation coefficients, half value layer, gamma-ray exposure build-up factor (EBF), and fast neutron removal cross …

Law's Halo And The Moral Machine, Bert I. Huang

Faculty Scholarship

How will we assess the morality of decisions made by artificial intelli­gence – and will our judgments be swayed by what the law says? Focusing on a moral dilemma in which a driverless car chooses to sacrifice its passenger to save more people, this study offers evidence that our moral intuitions can be influenced by the presence of the law.

Tuning The Reactivity Of Nanoenergetic Gas Generators Based On Bismuth And Iodine Oxidizers, Mkhitar A. Hobosyan, Karen S. Martirosyan

Physics and Astronomy Faculty Publications and Presentations

There is a growing interest on novel energetic materials called Nanoenergetic Gas- Generators (NGGs) which are potential alternatives to traditional energetic materials including pyrotechnics, propellants, primers and solid rocket fuels. NGGs are formulations that utilize metal powders as a fuel and oxides or hydroxides as oxidizers that can rapidly release large amount of heat and gaseous products to generate shock waves. The heat and pressure discharge, impact sensitivity, long term stability and other critical properties depend on the particle size and shape, as well as assembling procedure and intermixing degree between the components. The extremely high energy density and the …

Details Of Deformable Part Models For Automatically Georeferencing Historical Map Images, Nicholas Howe, Jerod Weinman, John Gouwar, Aabid Shamji

Computer Science: Faculty Publications

Libraries are digitizing their collections of maps from all eras, generating increasingly large online collections of historical cartographic resources. Aligning such maps to a modern geographic coordinate system greatly increases their utility. This work presents a method for such automatic georeferencing, matching raster image content to GIS vector coordinate data. Given an approximate initial alignment that has already been projected from a spherical geographic coordinate system to a Cartesian map coordinate system, a probabilistic shape-matching scheme determines an optimized match between the GIS contours and ink in the binarized map image. Us- ing an evaluation set of 20 historical maps …

Data Usage In Mir: History & Future Recommendations, Wenqin Chen, Jessica Keast, Jordan Moody, Corinne Moriarty, Felicia Villalobos, Virtue Winter, Xueqi Zhang, Xuanqi Lyu, Elizabeth Freeman, Jessie Wang, Sherry Cai, Katherine M. Kinnaird

Computer Science: Faculty Publications

The MIR community faces unique challenges in terms of data access, due in large part to country-specific copyright laws. As a result, there is an emerging divide in the MIR research community between labs that have access to music through large companies with abundant funds, and independent labs at smaller institutions who do not have such expansive access. This paper explores how independent researchers have worked to overcome limitations of access to music data without contributing to the crisis of reproducibility. Acknowledging that there is no single solution for every data access problem that smaller labs face, we propose a …

Crowdsourcing Image Schemas, Dagmar Gromann, Jamie C. Macbeth

Computer Science: Faculty Publications

With their potential to map experiental structures from the sensorimotor to the abstract cognitive realm, image schemas are believed to provide an embodied grounding to our cognitive conceptual system, including natural language. Few empirical studies have evaluated humans’ intuitive understanding of image schemas or the coherence of image-schematic annotations of natural language. In this paper we present the results of a human-subjects study in which 100 participants annotate 12 simple English sentences with one or more image schemas. We find that human subjects recruited from a crowdsourcing platform can understand image schema descriptions and use them to perform annotations of …

Reports Of The Aaai 2019 Spring Symposium Series, Ioana Baldini, Clark Barrett, Antonio Chella, Carlos Cinelli, David Gamez, Leilani H. Gilpin, Knut Hinkelmann, Dylan Holmes, Takashi Kido, Murat Kocaoglu, William F. Lawless, Alessio Lomuscio, Jamie C. Macbeth, Andreas Martin, Ranjeev Mittu, Evan Patterson, Donald Sofge, Prasad Tadepalli, Keiki Takadama, Shomir Wilson

Computer Science: Faculty Publications

Applications of machine learning combined with AI algorithms have propelled unprecedented economic disruptions across diverse fields in industry, military, medicine, finance, and others. With the forecast for even larger impacts, the present economic impact of machine learning is estimated in the trillions of dollars. But as autonomous machines become ubiquitous, recent problems have surfaced. Early on, and again in 2018, Judea Pearl warned AI scientists they must "build machines that make sense of what goes on in their environment," a warning still unheeded that may impede future development. For example, self-driving vehicles often rely on sparse data; self-driving cars have …

Linguistic Variation And Anomalies In Comparisons Of Human And Machine-Generated Image Captions, Minyue Dai, Sandra Grandic, Jamie C. Macbeth

Computer Science: Faculty Publications

Describing the content of a visual image is a fundamental ability of human vision and language systems. Over the past several years, researchers have published on major improvements on image captioning, largely due to the development of deep learning systems trained on large data sets of images and human-written captions. However, these systems have major limitations, and their development has been narrowly focused on improving scores on relatively simple “bag-of-words” metrics. Very little work has examined the overall complex patterns of the language produced by image-captioning systems and how it compares to captions written by humans. In this paper, we …

Constraining The P-Mode–G-Mode Tidal Instability With Gw170817, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, D. Tuyenbayev, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Robert Stone, W. H. Wang

Physics and Astronomy Faculty Publications and Presentations

We analyze the impact of a proposed tidal instability coupling p modes and g modes within neutron stars on GW170817. This nonresonant instability transfers energy fromthe orbit of the binary to internal modes of the stars, accelerating the gravitational-wave driven inspiral.We model the impact of this instability on the phasing of the gravitational wave signal using three parameters per star: an overall amplitude, a saturation frequency, and a spectral index. Incorporating these additional parameters, we compute the Bayes factor (lnBpg !pg) comparing our p-g model to a standard one. We find that the observed signal is consistent with waveform models …

All-Sky Search For Long-Duration Gravitational-Wave Transients In The Second Advanced Ligo Observing Run, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Malik Rakhmanov, K. E. Ramirez, Satzhan Sitmukhambetov, Robert Stone, D. Tuyenbayev, W. H. Wang, A. K. Zadrozny

Physics and Astronomy Faculty Publications and Presentations

We present the results of a search for long-duration gravitational-wave transients in the data from the Advanced LIGO second observation run; we search for gravitational-wave transients of 2–500 s duration in the 24–2048 Hz frequency band with minimal assumptions about signal properties such as waveform morphologies, polarization, sky location or time of occurrence. Signal families covered by these search algorithms include fallback accretion onto neutron stars, broadband chirps from innermost stable circular orbit waves around rotating black holes, eccentric inspiral-merger-ringdown compact binary coalescence waveforms, and other models. The second observation run totals about 118.3 days of coincident data between November …

Tests Of General Relativity With Gw170817, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, Malik Rakhmanov, K. E. Ramirez, Robert Stone, D. Tuyenbayev, W. H. Wang

Physics and Astronomy Faculty Publications and Presentations

The recent discovery by Advanced LIGOand AdvancedVirgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in the presence of matter. In this Letter, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large …

Eigenstates Transition Without Undergoing An Adiabatic Process, Fatemeh Mostafavi, Luqi Yuan, Hamidreza Ramezani

Physics and Astronomy Faculty Publications and Presentations

We introduce a class of non-Hermitian Hamiltonians that offers a dynamical approach to a shortcut to adiabaticity (DASA). In particular, in our proposed 2 × 2 Hamiltonians, one eigenvalue is absolutely real and the other one is complex. This specific form of eigenvalues helps us to exponentially decay the population in an undesired eigenfunction or amplify the population in the desired state while keeping the probability amplitude in the other eigenfunction conserved. This provides us with a powerful method to have a diabatic process with the same outcome as its corresponding adiabatic process. In contrast to standard shortcuts to adiabaticity, …

Search For Transient Gravitational-Wave Signals Associated With Magnetar Bursts During Advanced Ligo’S Second Observing Run, B. P. Abbott, R. Abbott, Teviet Creighton, Mario C. Diaz, Soma Mukherjee, Volker Quetschke, K. E. Ramirez, Malik Rakhmanov, Satzhan Sitmukhambetov, Robert Stone

Physics and Astronomy Faculty Publications and Presentations

We present the results of a search for short- and intermediate-duration gravitational-wave signals from four magnetar bursts in Advanced LIGO’s second observing run. We find no evidence of a signal and set upper bounds on the root sum squared of the total dimensionless strain (hrss) from incoming intermediate-duration gravitational waves ranging from 1.1 × 10−22 at 150 Hz to 4.4 × 10−22 at 1550 Hz at 50% detection efficiency. From the known distance to the magnetar SGR 1806–20 (8.7 kpc), we can place upper bounds on the isotropic gravitational-wave energy of 3.4 × 10^-44 erg at 150 Hz assuming optimal …

Kinetic Pathways Of Topology Simplification By Type-Ii Topoisomerases In Knotted Supercoiled Dna, Riccardo Ziraldo, Andreas Hanke, Stephen D. Levene

Physics and Astronomy Faculty Publications and Presentations

The topological state of covalently closed, double-stranded DNA is defined by the knot type $K$ and the linking-number difference $\\Delta Lk$ relative to unknotted relaxed DNA. DNA topoisomerases are essential enzymes that control the topology of DNA in all cells. In particular, type-II topoisomerases change both $K$ and $\\Delta Lk$ by a duplex-strand-passage mechanism and have been shown to simplify the topology of DNA to levels below thermal equilibrium at the expense of ATP hydrolysis. It remains a key question how small enzymes are able to preferentially select strand passages that result in topology simplification in much larger DNA molecules. …