Digital Commons Network^™

An Integrated Transport Solution To Big Data Movement In High-Performance Networks, Daqing Yun

Dissertations

Extreme-scale e-Science applications in various domains such as earth science and high energy physics among multiple national institutions within the U.S. are generating colossal amounts of data, now frequently termed as “big data”. The big data must be stored, managed and moved to different geographical locations for distributed data processing and analysis. Such big data transfers require stable and high-speed network connections, which are not readily available in traditional shared IP networks such as the Internet. High-performance networking technologies and services featuring high bandwidth and advance reservation are being rapidly developed and deployed across the nation and around the globe …

Context-Aware Collaborative Storage And Programming For Mobile Users, Mohammad A. Khan

Dissertations

Since people generate and access most digital content from mobile devices, novel innovative mobile apps and services are possible. Most people are interested in sharing this content with communities defined by friendship, similar interests, or geography in exchange for valuable services from these innovative apps. At the same time, they want to own and control their content. Collaborative mobile computing is an ideal choice for this situation. However, due to the distributed nature of this computing environment and the limited resources on mobile devices, maintaining content availability and storage fairness as well as providing efficient programming frameworks are challenging.

This …

Termination, Correctness And Relative Correctness, Nafi Diallo

Dissertations

Over the last decade, research in verification and formal methods has been the subject of increased interest with the need of more secure and dependable software. At the heart of software dependability is the concept of software fault, defined in the literature as the adjudged or hypothesized cause of an error. This definition, which lacks precision, presents at least two challenges with regard to using formal methods: (1) Adjudging and hypothesizing are highly subjective human endeavors; (2) The concept of error is itself insufficiently defined, since it depends on a detailed characterization of correct system states at each stage of …

Subspace Methods For Portfolio Design, Onur Yilmaz

Dissertations

Financial signal processing (FSP) is one of the emerging areas in the field of signal processing. It is comprised of mathematical finance and signal processing. Signal processing engineers consider speech, image, video, and price of a stock as signals of interest for the given application. The information that they will infer from raw data is different for each application. Financial engineers develop new solutions for financial problems using their knowledge base in signal processing. The goal of financial engineers is to process the harvested financial signal to get meaningful information for the purpose.

Designing investment portfolios have always been at …

Experimental And Modeling Studies In Membrane Distillation, Lin Li

Dissertations

A variety of microporous hydrophobic flat sheet membranes of polyvinylidene fluoride (PVDF) and expanded-polytetrafluoroethylene (e-PTFE) are studied to evaluate the influence of membrane properties on their performance in desalination by direct contact membrane distillation (DCMD) and vacuum membrane distillation (VMD) processes. The membrane thickness is varied between 23 μm to 125 μm; the pore size is varied from 0.05 μm to 0.45 μm. The porosity is generally high in the range of 0.7 - 0.8. DCMD experiments are performed over a hot brine temperature range of 65 °C to 85 °C and distillate temperature at 25 °C for various brine …

Studies On Purification And Functionalization Of Carbon Nanotubes And Their Aqueous Phase Behavior, Zheqiong Wu

Dissertations

Carbon nanotubes (CNTs) are known to have unique mechanical, thermal and electrical properties which make them attractive for a wide range of applications ranging from batteries to sensors. CNTs are rolled up graphene sheets where the single-walled CNTs (SWCNTs) and multi-walled CNTs (MWCNTs) are classified according to the number of concentric rings. In this dissertation, the focus is on several different aspects of MWCNTs. These include purification, functionalization and colloidal behavior.

MWCNTs are insoluble in solvents and therefore some degree of functionalization is required prior to their real-world applications. Oxidation debris is generated during carboxylation which is usually the first …

Mediating Chance Encounters Through Opportunistic Social Matching, Julia M. Mayer

Dissertations

Chance encounters, the unintended meeting between people unfamiliar with each other, serve as an important social lubricant helping people to create new social ties, such as making new friends or finding an activity, study or collaboration partner. Unfortunately, social barriers often prevent chance encounters in environments where people do not know each other and people have to rely on serendipity to meet or be introduced to interesting people around them. Little is known about the underlying dynamics of chance encounters and how systems could utilize contextual data to mediate chance encounters. This dissertation addresses this gap in research literature by …

The Hydromagnetic Structure Of The Polar Cap And Its Interaction With The Solar Wind, Kevin D. Urban

Dissertations

At this time it is uncertain as to how and to what extent ultra-low frequency (ULF) structures in the solar wind (periodicities ranging between several seconds to several hours) impact the coupled ionosphere-thermosphere-magnetosphere (ITM) system, especially in the high-latitude open flux region, where these structures can directly drive polar cap phenomena (e.g., via the direct injection of hydromagnetic energy along open field lines). First, a historical overview of open and closed models of the magnetosphere is provided, which develops the motivations and concepts associated with the expanding/contracting polar cap (ECPC) model that prevails today. In the ECPC model, the open …

Semi Supervised Weighted Maximum Variance Dimensionality Reduction, Pranitha Surya Andalam

Theses

In the recent years, we have huge amounts of data which we want to classify with minimal human intervention. Only few features from the data that is available might be useful in some scenarios. In those scenarios, the dimensionality reduction methods play a major role for extracting useful features. The two parameter weighted maximum variance (2P-WMV) is a generalized dimensionality reduction method of which principal component analysis (PCA) and maximum margin criterion (MMC) are special cases.. In this paper, we have extended the 2P-WMV approach from our previous work to a semi-supervised version. The objective of this work is specially …

Data Analytics With Mapreduce In Apache Spark And Hadoop Systems, Zongxuan Du

Theses

MapReduce comes from a traditional problem solving method: separating a big problem and solving each small parts. With the target of computing larger dataset in more efficient and cheaper way, this is implement into a programming mode to deal with massive quantity of data. The users get a map function and use it to abstract dataset into key / value logical pair and then use a reduce function to group all value with the same key. With this mode, task can be automatic spread the job into clusters grouped by lots of normal computers. MapReduce program can be easily implemented …

Simulation Of A Low Voltage Customer Microgrid Using Petri Nets, Joshua Mark

Theses

With renewable energy coming to the forefront of how power is generated and delivered to the modern consumer, Microgrids are emerging as an optimal and efficient method for implementing renewables and changing the infrastructure of the dated transmission and distribution grid. This thesis work presents mathematical models of Petri Nets for the simulation of a low voltage customer Microgrid. Using previous work created in this specific field, a Hybrid Petri Net is modified such that it consists of multiple distributed generators, storage, and the utility which is referred to as the main distribution grid in this thesis. A Discrete Petri …

Multisensory Integration In Weakly Electric Fish, Andrea Roeser

Theses

Animals integrate information from across sensory systems, such as vision and hearing, to improve perception. To understand how neural circuits in the central nervous system integrate information from different senses, the responses of midbrain neurons to two categories of electrosensory stimuli in Eigenmannia virescens were studied. The first category of stimulus is electrical signals with frequencies below 50 Hz that are encoded in the activity of ampullary receptors. The second category is amplitude modulations of the electric organ discharge, which are encoded by p-type tuberous receptors. Six multisensory neurons were found that responded to both categories of stimuli. However, when …

Effect Of Temperature On The Fracture Behavior Of Lead-Free Solder Joints, Patrick Thompson

Theses

The objective of the present study is to examine the effect of temperature on the fracture behavior of Cu-SAC305-Cu joints. To this end, double cantilever beam (DCB) specimens, consisting of a thin layer of Sn96.5Ag3.0Cu0.5 (SAC305) solder sandwiched between two copper bars, fabricated under standard surface mount (SMT) processing conditions are fractured under various temperatures with a MTS machine equipped with an environment chamber. The load-displacement behavior corresponding to crack initiation and the subsequent toughening before ultimate failure and the displacements near crack tip are recorded and used to calculate the fracture energy release rates. The fracture surfaces and the …

Koh Etching Of Silicon, Ying Wang

Theses

In this research, a series of comparative etching experiments on silicon wafers have been carried out using potassium hydroxide (KOH) for different experimental etching conditions for concentration, temperature and time on (100) orientation p-type silicon wafers. Besides the basic etching conditions, the position of the immersed wafer also has unpredictable effect on the etching process. This may be attributed to the relative contact position between the surface of the immersed wafer and the flow patterns of the stirred etching solution.

The surface morphology analysis indicates that the specific position of the wafer, with respect to the flow of the etchant, …

Uusing The Kdj As A Trading Strategy On Biotech Companies, Shijie Zha

Theses

Mean Reversion is the most commonly used model in quantitative trading. This model is associated with several factors, like ma5 and ma10 line. These factors are the most significant in stock markets. However, the disadvantages of this model are lag and inaccuracy.

In this research, we get the historical and current stock data by web crawler, analyze the quantitative data and build a new model involved with the KDJ. Taking biotech companies marketed in the United States and B-share marketed in China as the research subjects, the result shows increased profits compared with the Mean Reversion model. It also shows …

A Computational Model For Transdermal Diffusion Of Lidocaine And Tetracaine Topical Patches, Qian Dong

Theses

In recent years, transdermal drug delivery patches (TDDP) have developed rapidly. This is because the TDD system has more advantages than traditional drug delivery systems such as oral medicine and intravenous injection. In order to reach the circulatory system of the human body, drug molecules have to pass through the epidermis (outer layer) of the skin. The barrier properties of epidermis originate from low permeability of stratum corneum (SC) which is the outermost layer of the human skin. The objective of this thesis is to build a Finite Element (FE) model, utilizing commercial FE software (ANSYS), that can be implemented …

Effect Of Melt Method On Thoracolumbar Connective Tissue, Faria Sanjana

Theses

Approximately, 31 million adults in the United States suffer from low back pain (LBP). Altered connective tissue structure has been identified in adults with chronic LBP. Numerous novel treatments are being developed targeting the connective tissue and nervous system to relieve people from LBP. One such self-care treatment is the MELT method. The objective of this study was to determine whether thickness of thoracolumbar connective tissue and other biomechanical and viscoelastic properties of myofascial tissue in the low back region change in subjects with chronic LBP as a result of MELT.

Using ultrasound imaging and an algorithm developed in MATLAB, …

Collaborative Development Of A Small Business Emergency Planning Model, Arthur Henry Hendela

Dissertations

Small businesses, which are defined by the US Small Business Administration as entities with less than 500 employees, suffer interruptions from diverse risks such as financial events, legal situations, or severe storms exemplified by Hurricane Sandy. Proper preparations can help lessen the length of the interruption and put employees and owners back to work. Large corporations generally have large budgets available for planning, business continuity, and disaster recovery. Small businesses must decide which risks are the most important and how best to mitigate those risks using minimal resources.

This research uses a series of surveys followed by mathematical modeling to …

A Data Science Approach To Pattern Discovery In Complex Structures With Applications In Bioinformatics, Lei Hua

Dissertations

Pattern discovery aims to find interesting, non-trivial, implicit, previously unknown and potentially useful patterns in data. This dissertation presents a data science approach for discovering patterns or motifs from complex structures, particularly complex RNA structures. RNA secondary and tertiary structure motifs are very important in biological molecules, which play multiple vital roles in cells. A lot of work has been done on RNA motif annotation. However, pattern discovery in RNA structure is less studied. In the first part of this dissertation, an ab initio algorithm, named DiscoverR, is introduced for pattern discovery in RNA secondary structures. This algorithm works by …

Magnetic Reconnection In Small And Large Scales On The Sun, Xin Chen

Dissertations

Almost all solar activities observed are related to the solar magnetic field, especially the topological restructuring of magnetic fields, the so-called magnetic reconnection in solar physics. They are occurring at different scales related to various phenomena, during minimum or maximum of the solar cycle, from the photosphere to the solar corona.

For small-scale activities, type II spicules which display high velocity upflows observed at the limb, have the most possible underlying driving mechanism of magnetic reconnection. A set of tools is developed for detecting small-scale solar magnetic cancellations and the disk counterpart of type II spicules (the so-called Rapid Blueshifted …

Schema-Aware Keyword Search On Linked Data, Ananya Dass

Dissertations

Keyword search is a popular technique for querying the ever growing repositories of RDF graph data on the Web. This is due to the fact that the users do not need to master complex query languages (e.g., SQL, SPARQL) and they do not need to know the underlying structure of the data on the Web to compose their queries. Keyword search is simple and flexible. However, it is at the same time ambiguous since a keyword query can be interpreted in different ways. This feature of keyword search poses at least two challenges: (a) identifying relevant results among a multitude …

Thermochemical Properties Of Fluorinated Hydrocarbons, Hydroperoxides, And Fluorinated Hydroperoxides; Thermochemistry And Kinetics On Dissociation And Association Reactions Of Oxiranyl Radical, Heng Wang

Dissertations

Thermochemical properties on fluorinated hydrocarbons, alcohol, hydroperoxides, and alkyl hydroperoxides are determined. Reaction kinetics and modeling on the three member ring cyclic ether radical, oxiranyl radical, are studied under atmospheric and combustion environments.

Molecular geometries, vibration frequencies, internal rotor potentials, and thermo-chemical properties (ΔfHº298, S°(T) and C°p(T)) for fluorinated-hydrocarbons, thermochemical properties and bond energies, for alkyl and fluoro hydroperoxides and fluoro alcohols are determined with comparison of data from a number of different ab initio, density functional theory (DFT) and composite calculation methods, and basis sets.

Kinetic parameters for unimolecular decomposition and isomerization reactions of the oxiranyl radical are determined …

New Facet Of Solar Activities Revealed By High-Resolution Imaging At He I 10830 Å, Zhicheng Zeng

Dissertations

Major solar activities such as major flares and associated coronal mass ejections (CMEs), have a great impact on space weather, which requires us to develop the ability to predict them. Despite the extensive studies already made, however, many basic processes, such as energy accumulation processes in solar active regions and the triggering mechanism of solar activities, are still not well understood.

One reason why the basic processes are hard to be understood is that the large-scale activities are complicated, involving many small-scale energy releases, making it hard to understand the basic picture of the events. Small-scale solar activities, such as …

Gene Network Understanding And Analysis, Maria E. Somoza

Theses

Gene regulatory network (GRN) is a collection of regulators that interact with each other in the cell to govern the gene expression levels of mRNA and proteins. These regulators can either be DNA, RNA, protein and their complex. Transcriptional gene regulation is an important mechanisms in which an in-depth study can lead to various practical applications, and a greater understanding of how organisms control their cellular behavior. One of the most widely studied organisms in gene regulatory networks are the Mycobacterium tuberculosis and Corynebacterium glutamicum ATCC 13032.

Gene co-expression networks are of biological interests due to co-expressed genes which are …

Radiative Properties Of Silicon Related Materials, Scott Sanowitz

Theses

The objective of this thesis is to study the optical properties of silicon, as a function of temperature, in the infrared range of wavelengths. The wavelength range, considered in this study, is between 1 micron and 20 microns. The temperature range observed is from 50 degrees Celsius to 1000 degrees Celsius. Varying wafer thickness and doping are taken into account. The thickness of the native oxide, silicon dioxide, must be taken into account as well as its orientation (front side versus back side). The effect of layering wafers one onto another is investigated. It is shown that all these parameters …

Hand Control Of Bipedal Balance In Quiet Standing: Implementations For Lower Extremity Exoskeleton, Ala’A Al-Rashdan

Dissertations

Maintaining stable posture is important for humans, even though it is challenging because of our bipedal structure. One of the main balance related disorders is paraplegia due to spinal cord injury. People with a complete spinal cord injury have motor and sensory impairment that greatly reduces the ability to move their lower extremities. In recent years, lower extremity exoskeletons that apply torques generated by motors to the joints of the person have helped to them stand and walk.

This research is a part of an extended project to build a new exoskeleton for use by individuals with paraplegia due to …

Verification Of Emotion Recognition From Facial Expression, Yanjia Sun

Dissertations

Analysis of facial expressions is an active topic of research with many potential applications, since the human face plays a significant role in conveying a person’s mental state. Due to the practical values it brings, scientists and researchers from different fields such as psychology, finance, marketing, and engineering have developed significant interest in this area. Hence, there are more of a need than ever for the intelligent tool to be employed in the emotional Human-Computer Interface (HCI) by analyzing facial expressions as a better alternative to the traditional devices such as the keyboard and mouse.

The face is a window …

Normal-Strength And High-Strength Concrete Columns Under Cyclic Axial Load And Biaxial Moment, Mehdi Zarei

Dissertations

The technique of using Carbon Fiber Reinforced Polymer (CFRP) materials to repair and strengthen various concrete members has become popular in the structural retrofitting field as an effective way to enhance the strength and ductility of concrete members due to its superior mechanical properties. In this study a method was introduced to study the behavior of concrete columns with and without CFRP jackets under constant axial load and variable lateral load. The lateral load was applied monotonically and cyclically. To predict the behavior of concrete columns under monotonic and cyclic compressive loadings, a computer code was developed to produce the …

Terahertz Wireless Communication Through Atmospheric Atmospheric Turbulence And Rain, Jianjun Ma

Dissertations

This dissertation focusses on terahertz (THz) wireless communication technology in different weather conditions. The performance of the communication links is mainly studied under propagation through atmospheric turbulence and rain. However, as real outdoor weather conditions are temporally and spatially varying, it is difficult to obtain reproducible atmospheric conditions to verify results of independent measurements making it a challenge to measure and analyze the impact of outdoor atmospheric weather on communication links. Consequently, dedicated indoor weather chambers are designed to produce controllable weather conditions to emulate the real outdoor weather as closely as possible. To emulate turbulent air conditions, an enclosed …

Opto-Mechanical Design Of Synchrotron Radiation-Based Far-Infrared Spectroscopic Ellipsometer With Strong Magnetic-Field, Ahmad Abbas Chaudhry

Theses

The objective of this dissertation is to present opto-mechanical design of a synchrotron radiation based far-infrared spectroscopic ellipsometer with a strong external magnetic-field capability. Since high magnetic field has enabled major breakthrough in science such instrument will be highly important to the field of condensed matter physics and characterization of advanced electronic materials. This instrument will be installed at the multi-User facility with the most advanced synchrotron light source: Natonal Synchrotron Source (NSLS-II) at Brookhaven National Laboratory (BNL).The proposed here instrument is capable to measure full Mueller matrix spectroscopic ellipsometry spectra in high magnetic fields of up to 9 Tesla. …