Digital Commons Network^™

Data Replication Strategies In Cloud Computing, Yang Liu

Computer Science

Data replication is a widely used technique in various systems. For example, it can be employed in large-scale distributed file systems to increase data availability and system reliability, or it can be used in many network models (e.g. data grid, Amazon CloudFront) to reduce access latency and network bandwidth consumption, etc. I study a series of problems that related to the data replication method in Hadoop Distributed File System (HDFS) and in Amazon CloudFront service. Data failure, which is caused by hardware failure or malfunction, software error, human error, is the greatest threat to the file storage system. I present …

Distance-Aware Relay Placement And Scheduling In Wireless Networks., Shi Bai

Computer Science

The WiMAX technology and cognitive radio have been active topics in wireless networks. A WiMAX mesh network is able to provide larger wireless coverage, higher network capacity and Non-Line-Of-Sight (NLOS) communications. Cognitive radios enable dynamic spectrum access over a large frequency range. These characteristics make WiMAX mesh networks and cognitive radio networks able to provide users with low-cost, high-speed and long-range wireless communications, as well as better Quality of Service. However, there are still several challenges and problems to be solved in this area, such as relay station placement problems and scheduling problems. In this thesis, I studied a distance-aware …

Dom Structure Based Web Pattern Mining, Naresh Pillarikuppam

Computer Science

A rapid expansion in the Web has motivated several studies to understand and recognize the implementation structure underlying the interface. Though the presentation of the Web pages looks different, those Web pages may share the same semantic structure to organize information. Those common semantic structures are referred to as Web patterns. There are no strict rules for implementing the HTML structure of the web pages, and the implementation of each web page might not be consistent across the entire website. Also, the HTML implementation of one website varies from other websites. This makes it difficult to recognize the Web patterns …

Demonstrating Bid Rigging With A Shopping Agent Application Using Jade, Dinesh Sivanandam

Computer Science

This paper presents the implementation of a shopping-cart agent that demonstrated collusion in online bidding. Collusion is an agreement between two or more persons, sometimes illegal and therefore secretive, to limit open competition by deceiving, misleading, or defrauding others of their legal rights; or to obtain an objective forbidden by law, typically by defrauding or gaining an unfair advantage [15]. It is an agreement among firms to divide the market, set prices, or limit production. The paper has the shopping agent and its bid-rigging methods implemented using the Java Agent Development Framework (JADE), which helps develop agent-based applications. JADE uses …

Vector-Item Pattern Mining Algorithms And Their Applications, Jianfei Wu

Computer Science

Advances in storage technology have long been driving the need for new data mining techniques. Not only are typical data sets becoming larger, but the diversity of available attributes is increasing in many problem domains. In biological applications for example, a single protein may have associated sequence-, text-, graph-, continuous and item data. Correspondingly, there is growing need for techniques to find patterns in such complex data. Many techniques exist for mapping specific types of data to vector space representations, such as the bag-of-words model for text [58] or embedding in vector spaces of graphs [94, 91]. However, there are …

Modeling Of Dynamic Pricing Of Energy For A Smart Grid Using A Multi-Agent Framework, Harvinder Kaur

Computer Science

The use of smart grids is being promoted to address issues such as energy independence, global warming and emergency resilience. A smart grid is a digitized form of the power grid and is comprised of an intelligent monitoring system that keeps track of the two-way digital communications in the system. A multi-agent system is a collection of interacting intelligent agents that can be used in problem solving for systems that are difficult or impossible to be solved by an individual agent. Applications of multi-agent systems can range from transportation, logistics, graphics, networking and mobile technologies to modeling real world scenarios …

Analysis Of Security Vulnerabilities In Web Applications Using Threat Modeling, Samuel Sudhakar Kondamarri

Computer Science

Software security issues have been a major concern to the cyberspace community; therefore, a great deal of research on security testing has been performed, and various security testing techniques have been developed. A security process that is integrated into the application development cycle is required for creating a secure system. A part of this process is to create a threat profile for an application. The present project explains this process as a case study for analyzing a web application using Threat Modeling. This analysis can be used in the security testing approach that derives test cases from design level artifacts.

Positioning Of Relay Stations In Wireless Sensor Networks, Nikhil Koganti

Computer Science

A sensor is a device which can detect or measure a physical property and which records, indicates, or otherwise responds to the signal received. A wireless sensor in a network can communicate with the sensors located within its transmission range. In this paper, the capacity enhancement problem by adding a relay station to the sensor network was studied which can result in efficient and scalable design. Major concerns of the wireless sensors addressed in this paper are reducing the number of hops a message needs to make from one sensor to a different sensor before it reaches the base station, …

Grid Frequency And Voltage Support Using Photovoltaic Systems With Energy Storage Assist, Ravi Bhatt

Masters Theses

"An optimized operating scheme for a grid-connected community based photovoltaic (PV) system is described. The system can participate in grid ancillary services like frequency and voltage regulation functions based on the Smart Grid framework. The proposed model comprises of a PV plant with Li-ion batteries coupled to the grid by means of a three-phase inverter. A two-way communication between the PV plant and the grid is assumed. The PV/storage plant provides constant updates on its current kW/kVar capability and the grid transmits the demand for specific amounts of power and for specific lengths of time. The battery charging energy can …

The Sorption Of Chemical And Nuclear Contaminants From Soil And Water Using Nanosize Particles Of Hydroxyapatite, Chyrene Joseph

Masters Theses

"High surface area (>200 m²/g) crystals composed of nanosize (30-50nm) hydroxyapatite; (Ca₅(PO₄)₃OH) particles are being investigated as an alternative in cleaing [sic] contaminated groundwater and soil by removing toxic wastes and radionuclides. Static batch tests were carried out at 2, 4, 8, 24 and 120 hour time periods by reacting hydroxyapatite with individual solutions prepared with specific elements to evaluate the applicability of hydroxyapatite in removing potential contaminants. Chemical analyses on leachant solutions, leachate solutions, and post-reaction digested solids were conducted by Inductively Coupled Plasma-Mass Spectroscopy to determine the extent of ion removal. Removal of these ions is expected …

Driven Pile Load Test Data For Load And Resistance Factor Design In Missouri, Joseph Ronson Cravens

Masters Theses

"The Missouri Department of Transportation (MoDOT) has recently migrated from allowable stress design (ASD) to load and resistance factor design (LRFD) of driven piles. This transition was initiated when the Federal Highway Administration (FHWA) issued a policy stating that all new bridge designs shall be designed in accordance with the American Association of State Highway and Transportation Officials (AASHTO) LRFD Bridge Design Specifications to eliminate the difference in design methodologies for bridge superstructures and bridge substructures. However, the resistance factors for driven piles specified in the AASHTO LRFD specifications are based on nationwide pile data, consisting of a wide range …

Maggie And Her Students: Talking And Reasoning In A Reform-Based Mathematics Classroom, Debra Louise Semm Rich

Dissertations and Theses @ UNI

In this qualitative case study, I explored how Maggie, the teacher, and her students used language to advance students' conceptual understanding of mathematics in a reform-based mathematics classroom. Specifically I sought to describe how Maggie's reform-based mathematics classroom environment impacted the quantity and quality of mathematical language spoken by her students. Maggie's eighth-grade mathematics classroom was observed during a course of study on data and statistics. Three semi-structured interviews with Maggie, artifacts provided by her, and fourteen 52-minute classroom lessons, supported with field notes, were analyzed.

Environmental themes were revealed as they related to Maggie, her beliefs, goals, knowledge, and …

Optimal Control Of A Helicopter Unmanned Aerial Vehicle (Uav), David John Nodland

Masters Theses

"This thesis addresses optimal control of a helicopter unmanned aerial vehicle (UAV). Helicopter UAVs may be widely used for both military and civilian operations. Because these helicopters are underactuated nonlinear mechanical systems, high-performance controller design for them presents a challenge. This thesis presents an optimal controller design via both state and output feedback for trajectory tracking of a helicopter UAV using a neural network (NN). The state and output-feedback control system utilizes the backstepping methodology, employing kinematic and dynamic controllers while the output feedback approach uses an observer in addition to these controllers. The online approximator-based dynamic controller learns the …

Synthesis And Toxicity Studies Of Imidazolium-Based Ionic Liquids, Ninu Madria

Masters Theses

"There is a considerable recent interest in the applications of room temperature ionic liquids (RTILs) as green solvents in organic synthesis and as nonvolatile electrolytes in lithium ion batteries. A variety of commercially available imidazolium based RTILs have been used for these applications, mainly due to their negligible vapor pressures, high thermal stabilities, wide liquid range, wide electrochemical windows and high anodic stability. The state of the art lithium ion batteries require the use of electrolytes that have relatively low viscosities at temperatures as low as -35°C. This thesis describes the synthesis of novel oxygenated and fluorinated imidazolium based RTILs …

Novel Transparent Conductive Materials: Understanding And Prediction, Yaou Song

Masters Theses

"Transparent conductive oxides (TCOs) such as doped In₂O₃, ZnO, SnO₂ or CdO are highly attractive due to their special properties, which are electrical conductivity and optical transparency. The lack of complete understanding of the fundamentals behind this unique phenomena and rapidly increasing commercial demand draw a lot of interest in investigating this kind of materials. More efficient, environmentally friendly and less expensive transparent conductive materials are needed for a variety of applications, and a general understanding of the origins of the unusual behavior would help further search for potential transparent conductive (TC) candidates. Understanding the basic properties of conventional TCOs …

Virtual Dance And Motion-Capture, Marc Boucher

Contemporary Aesthetics (Journal Archive)

A general view of various ways in which virtual dance can be understood is presented in the first part of this article. It then appraises the uses of the term “virtual” in previous studies of digital dance. A more in-depth view of virtual dance as it relates to motion-capture is offered, and key issues are discussed regarding computer animation, digital imaging, motion signature, virtual reality and interactivity. The paper proposes that some forms of virtual dance be defined in relation to both digital technologies and contemporary theories of virtuality.

Cylinders And Spheres : Toddlers Engage In Problem Solving, Rosemary Geiken

Dissertations and Theses @ UNI

Every day more six million infants and toddlers (children under 3 years of age) enter some kind of out-of-home care, with 22% of this group attending center-based programs. Studies on the quality of care in centers indicate that 40% of these children are in poor quality settings while 51 % are in mediocre to medium quality settings. Two factors contributing to these low ratings are lack of age-appropriate materials and lack of learning opportunities. To address these data Piaget's theory of constructivism guided the design of a study to provide evidence of construction of knowledge that occurred when toddlers were …

Enrollment Of Students With Disabilities In Career And Technical Education, Cory C. Johnson

Dissertations and Theses @ UNI

The enrollment patterns of students with and without disabilities in Career and Technical Education (CTE) were examined. Data were collected from the transcripts and Individualized Education Plans (IEP) of 27 students with disabilities and the transcripts of 27 students without disabilities from three school districts at the end of their senior year. The data were analyzed using descriptive statistical analyses to describe differences between the enrollment patterns of students with and without disabilities as well as between students with different types and severity of disability. Overall, students in special education earned more CTE credits than students in general education. Additionally, …

Effective Professional Development For Teachers Of Students With Autism, Erin Marie Torruella

Dissertations and Theses @ UNI

The number of students with autism is on the rise. The main treatment for children with autism is their education. It is essential that teachers are prepared to work with students with autism. The purpose of this study was to determine the effectiveness of a teacher training workshop held by Area Education Agency 267. Fifty-one participants of the workshop training responded to a survey regarding their implementation of strategies learned, their understanding of the content and strategies learned, the change in their planning and delivery of instruction, and the impact on their students' achievement.

The study found that the training …

A'S From Zzzz's? The Causal Effect Of School Start Time On The Academic Achievement Of Adolescents, Scott E. Carrell, Teny Maghakian, James E. West

Economics

Recent sleep research finds that many adolescents are sleep-deprived because of both early school start times and changing sleep patterns during the teen years. This study identifies the causal effect of school start time on academic achievement by using two policy changes in the daily schedule at the US Air Force Academy along with the randomized placement of freshman students to courses and instructors. Results show that starting the school day 50 minutes later has a significant positive effect on student achievement, which is roughly equivalent to raising teacher quality by one standard deviation. (JEL I23, J13)

Effects Of Silar Cycle On The Electrical Characteristics Of Cd/Cdse/N-Si/Au-Sb Structure, Betül Güzeldi̇r, Mustafa Sağlam, Aytünç Ateş

Turkish Journal of Physics

Cd/CdSe/n-Si/Au-Sb structures have been fabricated by Successive Ionic Layer Adsorption and Reaction (SILAR) method under various SILAR cycles. The characteristics parameters of these structures such as barrier height, ideality factor, series resistance are calculated from the current-voltage (I-V) measurements and the barrier height, carrier concentration are calculated from reverse bias capacitance-voltage (C-V) measurements at 300 kHz frequency and room temperature. Furthermore, the density distribution and rectifying ratio of these structure have been calculated from the I-V measurements as a function of SILAR cycle. It has been seen that the changes of characteristic parameters such as barrier height, ideality factor and …

Estimating Global Solar Radiation From Common Meteorological Data In Aranjuez, Spain, Javier Almorox

Turkish Journal of Physics

This study aimed to calibrate existing models and develop a new model for estimating global solar radiation data using commonly and available measured meteorological records such as precipitation or temperature. Fifteen empirical global radiation models based on meteorological variables were generated and validated using daily data in 2003-2008 at the Aranjuez station (Community of Madrid, Spain). Validation criteria included coefficient of determination, root mean square error, mean bias error, mean absolute bias error, mean percentage error, and mean absolute percentage error. The best result was derived from the model proposed, which uses extraterrestrial solar radiation, saturation vapor pressures, transformed rainfall …

Resonance Phenomena And Time Asymmetric Quantum Mechanics, Arno Rudolf Bohm, Fati̇h Erman, Haydar Uncu

Turkish Journal of Physics

This article is a review of time asymmetric quantum theory and its consequences applied to the resonance and decay phenomena. We first give some phenomenological results about resonances and decaying states to support the popular idea that resonances characterized by a width \Gamma and decaying states characterized by a lifetime \tau are different appearances of the same physical entity. Based on Weisskopf-Wigner (WW) methods, one obtains approximately \frac{\hbar}{\tau}\approx \Gamma. However, using standard axioms of quantum physics it is not possible to establish a rigorous theory to which the various WW methods can be considered as approximations. In standard quantum theory, …

Application Of Active-Osl Approximation To Some Experimental Optical Stimulated Luminescence Decay, Ayşe Güneş Tanir, Mustafa Hi̇cabi̇ Bölükdemi̇r

Turkish Journal of Physics

In this work, Active-OSL Approximation (AOSLA) suggested by our previous study was applied to experimental optical stimulated luminescence decay from some sediment samples. The explanation of the AOSLA was based on the radioactive decay law of successive disintegration. It allows obtaining the peak forms of luminescence mechanism. This work shows that detrapping constants that have great importance in dating and dosimeters studies can be rapidly and clearly found using the AOSLA. Also, it can be concluded that the OSL is a process similar to the radioactive decay law of successive disintegration.

The Role Of Co-Infection In The Spread Of Hiv In Sub-Saharan Africa, Diego Fernando Cuadros

Theses and Dissertations--Biology

The cause of the high HIV prevalence in sub-Saharan Africa is incompletely understood, with heterosexual penile-vaginal transmission proposed as the main mechanism. Heterosexual HIV transmission has a very low probability; further, a single estimation of heterosexual probability of HIV transmission fails to reproduce the variation associated with important biological cofactors. In particular, studies of HIV incidence suggest that co-infection with other infectious diseases influence the HIV transmission, and therefore might substantially vary the pattern of the spread of the infection. To assess the effect of co-infection on the spread of HIV, I developed and analyzed several mathematical and statistical models …

Differential Geometry Of Moving Surfaces And Its Relation To Solitons, Andrei Ludu

Publications

In this article we present an introduction in the geometrical theory of motion of curves and surfaces in R3, and its relations with the nonlinear integrable systems. The working frame is the Cartan's theory of moving frames together with Cartan connection. The formalism for the motion of curves is constructed in the Serret-Frenet frames as elements of the bundle of adapted frames. The motion of surfaces is investigated in the Gauss-Weingarten frame. We present the relations between types of motions and nonlinear equations and their soliton solutions.

Convergence Analysis Of Fully Discrete Finite Element Approximations For An Unsteady Doubly Diffusive Convection Model, Tobin Jackson

Dissertations

No abstract provided.

Multi-Objective Optimization Using Evolutionary Algorithms For Geographical Zone Partitioning, Nitin S. Sharma

Dissertations

No abstract provided.

A Longitudinal Study Of Multidisciplinary Engineering Design Teams Using Gersick's Punctuated Equilibrium Model Of Group Development, Thomas A. Nance

Dissertations

No abstract provided.

The Effect Of Student Mobility On Student Achievement, Lisa Eddy

University of Kentucky Doctoral Dissertations

Student mobility and its relationship to academic success have been researched since World War II with varied findings (Goebel, 1978). Establishing the relationship between mobility and achievement is difficult due to the fact that mobility is related to many factors. Mobility has been found to be prevalent among students who traditionally demonstrate achievement gaps (specifically students of low-income status) (Long, 1992; Smith, Fien & Paine, 2008).

Mobility’s relationship to achievement is complex. Led by a single definition of mobility, admittance to more than one school in the given district over the period of one academic year, this research study sought …