Physical Sciences and Mathematics Commons^™

Density And Diversity Of Penaeid Shrimp And Fish Species In Near-Shore Seagrass Beds Of Northern Biscayne Bay, Florida (Usa), Robin Cascioli

HCNSO Student Theses and Dissertations

Seagrass beds serve critical functions in coastal Florida ecosystems. The beds serve as nursery habitat for many juvenile reef fish species and provide protection for many types of benthic organisms found in Biscayne Bay. They help stabilize sediment that would otherwise increase turbidity around coral reefs, filter the water of contaminants, and help support an entire food web. Three species of seagrass were found at the study sites in northern Biscayne Bay: Thalassia testudinum, Halodule wrightii, and Syringodium filiforme. This study focused on understanding the organism habitat interaction by determining the species diversity, seasonal densities, and the …

On The Independent Domination Number Of Regular Graphs, Wayne Goddard, Michael A. Henning, Jeremy Lyle, Justin Southey

Faculty Publications

A set S of vertices in a graph G is an independent dominating set of G if S is an independent set and every vertex not in S is adjacent to a vertex in S. In this paper, we consider questions about independent domination in regular graphs.

Effects Of Stereo And Screen Size On The Legibility Of Three-Dimensional Streamtube Visualization, Jian Chen, Haipeng Cai, Alexander P. Auchus, David H. Laidlaw

Faculty Publications

We report the impact of display characteristics (stereo and size) on task performance in diffusion magnetic resonance imaging (DMRI) in a user study with 12 participants. The hypotheses were that (1) adding stereo and increasing display size would improve task accuracy and reduce completion time, and (2) the greater the complexity of a spatial task, the greater the benefits of an improved display. Thus we expected to see greater performance gains when detailed visual reasoning was required. Participants used dense streamtube visualizations to perform five representative tasks: (1) determine the higher average fractional anisotropy (FA) values between two regions, (2) …

Swift Follow-Up Observations Of Candidate Gravitational-Wave Transient Events, P. A. Evans, J. K. Fridriksson, N. Gehrels, J. Homan, J. P. Osborne, M. Siegel, A. Beardmore, P. Handbauer, J. Gelbord, J. A. Kennea, M. Smith, Q. Zhu, J. Aasi, J. Abadie, B. P. Abbott, R. Abbott, T. D. Abbott, M. Abernathy, T. Accadia, F. Acernese, C. Adams, T. Adams, P. Addesso, R. Adhikari, C. Affeldt, M. Agathos, K. Agatsuma, P. Ajith, B. Allen, A. Allocca, E. Amador Ceron, Tiffany Z. Summerscales

Faculty Publications

We present the first multi-wavelength follow-up observations of two candidate gravitational-wave (GW) transient events recorded by LIGO and Virgo in their 2009-2010 science run. The events were selected with low latency by the network of GW detectors (within less than 10 minutes) and their candidate sky locations were observed by the Swift observatory (within 12 hr). Image transient detection was used to analyze the collected electromagnetic data, which were found to be consistent with background. Off-line analysis of the GW data alone has also established that the selected GW events show no evidence of an astrophysical origin; one of them …

Ghost Tiger Beetle (Cicindela Lepida): Species Conservation Assessment, Melissa J. Panella

Nebraska Game and Parks Commission: Publications

The primary goal in development of at-risk species conservation assessments is to compile biological and ecological information that may assist conservation practitioners in making decisions regarding the conservation of species of interest. The Nebraska Natural Legacy Project recognizes the ghost tiger beetle, a.k.a. white tiger beetle, (Cicindela lepida) as a Tier I at-risk species of high conservation priority. Some general management recommendations are made here regarding ghost tiger beetles; however, conservation practitioners will need to use professional judgment to make specific management decisions based on objectives, location, and a multitude of variables. This resource was designed to share available knowledge …

Determining Stellar Velocity Dispersion In Active Galaxies: Is The [Oiii] Width A Valid Surrogate?, Kelsi Flatland

Physics

The tight empirical relation between the stellar velocity dispersion (sigma) of the bulge and the mass of the supermassive black hole (BH) at its center indicates a close connection between galactic evolution and BH growth. The evolution of this relation with cosmic time provides valuable clues to its origin. While the mass of the BH can be easily estimated using the Doppler broadening of the Hbeta emission line in type I active galactic nuclei (AGNs), measuring sigma simultaneously is challenging, since the nuclear emission outshines the host galaxy. Thus, it is highly desirable to find an alternative way to estimate …

Using Variable-Rate Alerting To Counter Boredom In Human Supervisory Control, Armen A. Mkrtchyan, Jamie C. Macbeth, Erin T. Solovey, Jason C. Ryan, M. L. Cummings

Computer Science: Faculty Publications

A low task load, long duration experiment was conducted to evaluate the impact of cyclical attention switching strategies on operator performance in supervisory domains. The impetus for such a study stems from the lack of prior work to improve human-system performance in low task load supervisory domains through the use of design interventions. In this study, a design intervention in the form of auditory alerts is introduced and the effects of the alerts are examined. The test bed consists of a video game-like simulation environment, which allows a single opera-tor the ability to supervise multiple unmanned vehicles. Each participant in …

Eliciting Usable Gestures For Multi-Display Environments, Teddy Seyed, Chris Burns, Mario Costa Sousa, Frank Maurer, Anthony Tang

Research Collection School Of Computing and Information Systems

Multi-display environments (MDEs) have advanced rapidly in recent years, incorporating multi-touch tabletops, tablets, wall displays and even position tracking systems. Designers have proposed a variety of interesting gestures for use in an MDE, some of which involve a user moving their hands, arms, body or even a device itself. These gestures are often used as part of interactions to move data between the various components of an MDE, which is a longstanding research problem. But designers, not users, have created most of these gestures and concerns over implementation issues such as recognition may have influenced their design. We performed a …

Cross-Lingual Identification Of Ambiguous Discourse Connectives For Resource-Poor Language, Lanjun Zhou, Wei Gao, Binyang Li, Zhongyu Wei, Kam-Fai Wong

Research Collection School Of Computing and Information Systems

The lack of annotated corpora brings limitations in research of discourse classification for many languages. In this paper, we present the first effort towards recognizing ambiguities of discourse connectives, which is fundamental to discourse classification for resource-poor language such as Chinese. A language independent framework is proposed utilizing bilingual dictionaries, Penn Discourse Treebank and parallel data between English and Chinese. We start from translating the English connectives to Chinese using a bi-lingual dictionary. Then, the ambiguities in terms of senses a connective may signal are estimated based on the ambiguities of English connectives and word alignment information. Finally, the ambiguity …

Visualization For Anomaly Detection And Data Management By Leveraging Network, Sensor And Gis Techniques, Zhaoxia Wang, Chee Seng Chong, Rick S. M. Goh, Wanqing Zhou, Dan Peng, Hoong Chor Chin

Research Collection School Of Computing and Information Systems

This paper studies the importance of visualization for discerning and interpreting patterns of data and its application for solving real problems, such as anomaly detection and data management. There are various ways to realize visualization to cater to the needs of numerous real life applications. Depending on needs, a combination of some of these ways may be required for presenting an effective visualization. The authors present visualization schemes for anomaly detection/condition monitoring and data management by leveraging network techniques and combining them with modern techniques such as sensor, database, mobile communication, GPS and GIS techniques. Two case studies are presented …

Finding Thoughtful Comments From Social Media, Gottipati Swapna, Jing Jiang

Research Collection School Of Computing and Information Systems

Online user comments contain valuable user opinions. Comments vary greatly in quality and detecting high quality comments is a subtask of opinion mining and summarization research. Finding attentive comments that provide some reasoning is highly valuable in understanding the user’s opinion particularly in sociopolitical opinion mining and aids policy makers, social organizations or government sectors in decision making. In this paper we study the problem of detecting thoughtful comments. We empirically study various textual features, discourse relations and relevance features to predict thoughtful comments. We use logistic regression model and test on the datasets related to sociopolitical content. We found …

Identification Of Tcp Protocols, Juan Shao

School of Computing: Dissertations, Theses, and Student Research

Recently, many new TCP algorithms, such as BIC, CUBIC, and CTCP, have been deployed in the Internet. Investigating the deployment statistics of these TCP algorithms is meaningful to study the performance and stability of the Internet. Currently, there is a tool named Congestion Avoidance Algorithm Identification (CAAI) for identifying the TCP algorithm of a web server and then for investigating the TCP deployment statistics. However, CAAI using a simple k-NN algorithm can not achieve a high identification accuracy. In this thesis, we comprehensively study the identification accuracy of five popular machine learning models. We find that the random forest model …

Dynamic Data Race Detection And Healing, Du Li

School of Computing: Dissertations, Theses, and Student Research

Perpetual availability is an important operational goal in today's computer systems. However, achieving this goal is challenging because modern software systems contain faults that can cause them to fail. For example, multi-threading is widely used in modern software to fully utilize the computing capability of multicore processors. However, employing multi-threading can lead to concurrency faults such as deadlock and data race that are notoriously difficult to to isolate, detect, and repair.Data races, which involves two concurrent accesses to the same data where at least one is a write, are the most common concurrency faults.

As our first step, we investigate …

Use Of Rss Feeds To Push The Online Content To Users, Dan Ma

Research Collection School Of Computing and Information Systems

Many websites use Really Simple Syndication (RSS) feeds to actively push their online content to users rather than waiting for users to pull the content passively. In this paper, I construct a theoretical game model to study the profitability of an RSS-PUSH delivery mechanism. The model assumes a general profit structure for websites and heterogeneous users. To access valuable online content, users incur a variety of costs. They choose either to visit the website in the conventional way (the PULL model) or, if it is supported by the website, to use RSS (the PUSH model). Interestingly, I show that although …

A Survey Of Recommender Systems In Twitter, Su Mon Kywe, Ee Peng Lim, Feida Zhu

Research Collection School Of Computing and Information Systems

Twitter is a social information network where short messages or tweets are shared among a large number of users through a very simple messaging mechanism. With a population of more than 100M users generating more than 300M tweets each day, Twitter users can be easily overwhelmed by the massive amount of information available and the huge number of people they can interact with. To overcome the above information overload problem, recommender systems can be introduced to help users make the appropriate selection. Researchers have began to study recommendation problems in Twitter but their works usually address individual recommendation tasks. There …

Extracting And Normalizing Entity-Actions From Users' Comments, Swapna Gottipati, Jing Jiang

Research Collection School Of Computing and Information Systems

With the growing popularity of opinion-rich resources on the Web, new opportunities and challenges arise and aid people in actively using such information to understand the opinions of others. Opinion mining process currently focuses on extracting the sentiments of the users on products, social, political and economical issues. In many instances, users not only express their sentiments but also contribute their ideas, requests and suggestions through comments. Such comments are useful for domain experts and are referred to as actionable content. Extracting actionable knowledge from online social media has attracted a growing interest from both academia and the industry. We …

Discrete Sparse Fourier Hermite Approximations In High Dimensions, Ashley Prater

Mathematics - Dissertations

In this dissertation, the discrete sparse Fourier Hermite approximation of a function in a specified Hilbert space of arbitrary dimension is defined, and theoretical error bounds of the numerically computed approximation are proven. Computing the Fourier Hermite approximation in high dimensions suffers from the well-known curse of dimensionality. In short, as the ambient dimension increases, the complexity of the problem grows until it is impossible to numerically compute a solution. To circumvent this difficulty, a sparse, hyperbolic cross shaped set, that takes advantage of the natural decaying nature of the Fourier Hermite coefficients, is used to serve as an index …

Nucleophilic Carbon-Carbon Bond-Forming Reactions Of 2-Methylenetetrahydropyrans, Laura Jean Bateman

Chemistry - Dissertations

Reactions with 2-methylenetetrahydropyrans are underutilized in the literature, especially with respect to general methods demonstrating their nucleophilic nature. This work provides three general methods toward the synthesis of 2-β-oxygenated pyranyl substrates, which are key structural components of many biologically active polyketides and natural products.

The use of exocyclic enol ethers as nucleophiles was first demonstrated as a general process in three-component coupling reactions with secondary nucleophiles. The 2-β-hydroxy tetrahydropyran products were obtained in good to excellent yields through promotion with stoichiometric levels of titanium(IV) chloride at reduced temperatures. Only activated aldehydes or ketones worked as efficient coupling partners for this …

Synthesis, Design, And Biological Evaluation Of Inhibitors And Activators Of Src Homology 2 Domain-Containing Inositol Phosphatase (Ship) And Synthetic Studies Of Apicularen A And Maoecrystal V, Dennis Racca Viernes

Chemistry - Dissertations

This dissertation involves work both on the syntheses of small molecules with potential therapeutic applications and synthetic studies on natural products with unusual core skeletons.

The first part of this work involves the synthesis, design, and biological evaluation of aminosteroids as inhibitors for the SH2-containing inositol phosphatase 1 (SHIP1). SHIP1, a 145 kDa protein, is involved in regulating the formation of new blood cells. High- throughput screening identified several SHIP inhibitors including NSC23922, a mixture of 3a- and 3β-aminocholestane. Both 3a- and 3β-aminocholestane were synthesized from dihdyrocholesterol and the 3a- form was verified as …

The Path To An Orally Administered Protein Therapeutic For The Treatment Of Diabetes Mellitus, Susan Clardy James

Chemistry - Dissertations

Protein therapeutics like insulin and glucagon-like peptide-1 analogues are currently used as injectable medications for the treatment of diabetes mellitus. An orally administered protein therapeutic is predicted to increase patient adherence to medication and bring a patient closer to metabolic norms through direct effects on hepatic glucose production. The major problem facing oral delivery of protein therapeutics is gastrointestinal tract hydrolysis/proteolysis and the inability to passage the enterocyte. Herein we report the potential use of vitamin B₁₂ for the oral delivery of protein therapeutics.

We first investigated the ability of insulin to accommodate the attachment of B₁₂ at …

Stress-Lifetime Joint Distribution Model For Performance Degradation Failure, Quan Sun, Yanzhen Tang, Jing Feng, Paul Kvam

Department of Math & Statistics Faculty Publications

The high energy density self-healing metallized film pulse capacitor has been applied to all kinds of laser facilities for their power conditioning systems under several stress levels, such as 23kV, 30kV and 35kV, whose reliability performance and maintenance costs are affected by the reliability of capacitors. Due to the costs and time restriction, how to assess the reliability of highly reliable capacitors under a certain stress level as soon as possible becomes a challenge. Accelerated degradation test provides a way to predict its lifetime and reliability effectively. A model called stress-lifetime joint distribution model and an analysis method based on …

Physics Faculty Use Of Example Solutions In Teaching Introductory Physics, William O. Mamudi

Masters Theses

This study investigates how physics faculty perceive and use features of example problem solutions. Thirty physics instructors from diverse institutions participated in semi-structured interviews. In addition to open-ended questions, three example problem solution artifacts were used to focus on specific solution features. Data were analyzed to identify instructors’ goals for the use of example solutions and whether their goals were consistent with the solution features that they valued and used. The study concludes that many faculty have three major goals: keeping students cognitively involved, helping students become better problem solvers, and supporting students in learning physics. The study also found …

Motion Capture Study Of Human Movement Recognition, Nicholas Kinerd

All Theses

In this thesis, we address questions about recognition of human movement through motion
capture. We begin by capturing the martial arts movements of four actors as they each perform
three different techniques. We then conduct a survey to determine if participants in
the survey are able to distinguish the various martial arts techniques and differentiate the
actors that portray said techniques. A secondary consideration of our survey is to determine
if the participants can distinguish the sex of the actors as they perform the martial arts
techniques. Our hypothesis is that people are able to distinguish actors and sex; however, …

Evaluation Of 26al Method As Star Formation Rate Indicator, Manjeet Singh

All Theses

The aim of this work is to evaluate the '26Al method' used to determine the Galactic Star Formation Rate (SFR) and compare it to other alternative methods. 26Al is a radioactive isotope produced mainly in massive star winds and in the ensuing core collapse supernova explosion. The radioactive 26Al decays with a life time of 106 years by emitting γ- ray photons in 1.808 MeV band. The 26Al method involves using the Galactic 26Al radioactive flux as a tracer. This approach based on the γ- ray line measurements does not suffer from extinction and small number statistics.
To evaluate the …

Semantic Similarity Detection In Natural Language Documents, Lianyu Zhao

All Theses

Data leak prevention (DLP) solutions monitor and control data flow. Current techniques find data that matches user defined syntactic patterns. Unfortunately, large classes of DLP relevant data are defined by information semantics, rather than data syntax. Syntax refers to data format, whereas semantics refers to data meaning. The class of social security numbers can be adequately expressed using data syntax, whereas a new industrial process can only be adequately described using information semantics. In this paper, we propose methods for extracting and identifying document semantics using training sets of limited size (tens of documents). The first method is based on …

Hydromechanical Well Testing Using A 3d Fiber Optic Extensometer, Glenn Skawski

All Theses

Some fractured rock formations hold important resources, such as water, hydrocarbons or heat, whereas others are good candidates for waste disposal. Hydromechanical well tests have been developed to improve characterization of formation properties and parameter distributions by measuring displacement along with pressure while stressing a well. The displacement that occurs during a well test depends on the geometry of fractures or other sources of permeability, as well as the distribution of compliance or elastic modulus. Current methods of hydromechanical well testing, measures axial displacements along a wellbore, which may cause ambiguity in interpretations when 3-D components of deformation are present. …

Objective Bayesian Inference On The Common Mean Of Normal Distributions, Shiyi Tu

All Theses

One of the oldest problems in statistical area is to make inference on a common mean of several different normal populations with unknown and probably unequal variances. There are several different ways to make inference on the common mean. The most common methods are point estimation, hypothesis testing, and interval estimation. Point estimation uses sample data to calculate a single value serving as a best guess for the unknown population mean. Hypothesis testing assumes all populations have the same mean as the null hypothesis. Interval estimation is an interval of possible values of the unknown mean.
In this paper, we …

An Efficient Image Segmentation Algorithm Using Bidirectional Mahalanobis Distance, Rahul Suresh

All Theses

In this thesis, we present an efficient graph-based image-segmentation algorithm that improves upon the drawbacks of the minimum spanning tree based segmentation algorithm, namely leaks that occur due to the criterion used to merge regions, and the sensitivity of the output to the parameter k. To address these problems, we propose the use of bidirectional Mahalanobis distance, along with a Gaussian model for each region, and an intuitive normalized parameter τ that replaces k and works for all images without having to be changed. Furthermore, we propose an approximation to the algorithm that enables it to run efficiently in O(NlogN) …

Ultraluminous X-Ray Sources In Andromeda Galaxy: Two Recent Discoveries And Their Implications, Amanpreet Kaur

All Theses

Ultraluminous X-ray sources are believed to be associated with X-ray binaries, in which an accreting black hole generates X-ray luminosities in excess of 10 39 erg/s. The nature of the companion star and the underlying physics of the accretion process is not yet established with certainty. In particular, whether or not the accretion is super/sub Eddington is an open question, as is the mass of the companion star. We discuss the first two ULXs recently discovered in M31 and investigate the nature of their underlying sources. We present the X-ray observations for ULX-1 in detail and discuss its implications for …

Ultrafast Laser-Induced Damage And The Influence Of Spectral Effects, Jeremy R. Gulley

Faculty Articles

Numerous studies have investigated the prerequisite role of photoionization in ultrafast laser-induced damage (LID) of bulk dielectrics. This study examines the role of spectral width and instantaneous laser frequency in LID using a frequency dependent multiphoton ionization (MPI) model and numerical simulation of initially 800 nm laser pulses propagating through fused silica. Assuming a band gap of 9 eV, MPI by an 800 nm field is a six-photon process, but when the instantaneous wavelength is greater than 827 nm an additional photon is required for photoionization, reducing the probability of the event by many orders of magnitude. Simulation results suggest …