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Automated Defense Against Worm Propagation.

Worms have caused significant destruction over the last few years. Network security elements such as firewalls, IDS, etc have been ineffective against worms. Some worms are so fast that a manual intervention is not possible. This brings in the need for a stronger security architecture which can automatically react to stop worm propagation. The method has to be signature independent so that it can stop new worms. In this thesis, an automated defense system (ADS) is developed to automate defense… more

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Date: December 2005

Creator: Patwardhan, Sudeep

Item Type: Thesis or Dissertation

Partner: UNT Libraries

Comparison and Evaluation of Existing Analog Circuit Simulator using Sigma-Delta Modulator

In the world of VLSI (very large scale integration) technology, there are many different types of circuit simulators that are used to design and predict the circuit behavior before actual fabrication of the circuit. In this thesis, I compared and evaluated existing circuit simulators by considering standard benchmark circuits. The circuit simulators which I evaluated and explored are Ngspice, Tclspice, Winspice (open source) and Spectre® (commercial). I also tested standard benchmarks using the… more

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Date: December 2006

Creator: Ale, Anil Kumar

Item Type: Thesis or Dissertation

Partner: UNT Libraries

A Multi-Variate Analysis of SMTP Paths and Relays to Restrict Spam and Phishing Attacks in Emails

The classifier discussed in this thesis considers the path traversed by an email (instead of its content) and reputation of the relays, features inaccessible to spammers. Groups of spammers and individual behaviors of a spammer in a given domain were analyzed to yield association patterns, which were then used to identify similar spammers. Unsolicited and phishing emails were successfully isolated from legitimate emails, using analysis results. Spammers and phishers are also categorized into se… more

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Date: December 2006

Creator: Palla, Srikanth

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Occlusion Tolerant Object Recognition Methods for Video Surveillance and Tracking of Moving Civilian Vehicles

Recently, there is a great interest in moving object tracking in the fields of security and surveillance. Object recognition under partial occlusion is the core of any object tracking system. This thesis presents an automatic and real-time color object-recognition system which is not only robust but also occlusion tolerant. The intended use of the system is to recognize and track external vehicles entered inside a secured area like a school campus or any army base. Statistical morphological ske… more

Date: December 2007

Creator: Pati, Nishikanta

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

System and Methods for Detecting Unwanted Voice Calls

Voice over IP (VoIP) is a key enabling technology for the migration of circuit-switched PSTN architectures to packet-based IP networks. However, this migration is successful only if the present problems in IP networks are addressed before deploying VoIP infrastructure on a large scale. One of the important issues that the present VoIP networks face is the problem of unwanted calls commonly referred to as SPIT (spam over Internet telephony). Mostly, these SPIT calls are from unknown callers who … more

Date: December 2007

Creator: Kolan, Prakash

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Models to Combat Email Spam Botnets and Unwanted Phone Calls

With the amount of email spam received these days it is hard to imagine that spammers act individually. Nowadays, most of the spam emails have been sent from a collection of compromised machines controlled by some spammers. These compromised computers are often called bots, using which the spammers can send massive volume of spam within a short period of time. The motivation of this work is to understand and analyze the behavior of spammers through a large collection of spam mails. My research … more

Date: May 2008

Creator: Husna, Husain

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Non-Uniform Grid-Based Coordinated Routing in Wireless Sensor Networks

Wireless sensor networks are ad hoc networks of tiny battery powered sensor nodes that can organize themselves to form self-organized networks and collect information regarding temperature, light, and pressure in an area. Though the applications of sensor networks are very promising, sensor nodes are limited in their capability due to many factors. The main limitation of these battery powered nodes is energy. Sensor networks are expected to work for long periods of time once deployed and it bec… more

Date: August 2008

Creator: Kadiyala, Priyanka

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Employment of dual frequency excitation method to improve the accuracy of an optical current sensor, by measuring both current and temperature.

Optical current sensors (OCSs) are initially developed to measure relatively large current over a wide range of frequency band. They are also used as protective devices in the event a fault occurs due to a short circuit, in the power generation and distribution industries. The basic principal used in OCS is the Faraday effect. When a light guiding faraday medium is placed in a magnetic field which is produced by the current flowing in the conductor around the magnetic core, the plane of polariz… more

Date: December 2008

Creator: Karri, Avinash

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Study of the effects of background and motion camera on the efficacy of Kalman and particle filter algorithms.

This study compares independent use of two known algorithms (Kalmar filter with background subtraction and Particle Filter) that are commonly deployed in object tracking applications. Object tracking in general is very challenging; it presents numerous problems that need to be addressed by the application in order to facilitate its successful deployment. Such problems range from abrupt object motion, during tracking, to a change in appearance of the scene and the object, as well as object to sc… more

Date: August 2009

Creator: Morita, Yasuhiro

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Inferring Social and Internal Context Using a Mobile Phone

This dissertation is composed of research studies that contribute to three research areas including social context-aware computing, internal context-aware computing, and human behavioral data mining. In social context-aware computing, four studies are conducted. First, mobile phone user calling behavioral patterns are characterized in forms of randomness level where relationships among them are then identified. Next, a study is conducted to investigate the relationship between the calling behav… more

Date: December 2009

Creator: Phithakkitnukoon, Santi

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

An investigation into graph isomorphism based zero-knowledge proofs.

Zero-knowledge proofs protocols are effective interactive methods to prove a node's identity without disclosing any additional information other than the veracity of the proof. They are implementable in several ways. In this thesis, I investigate the graph isomorphism based zero-knowledge proofs protocol. My experiments and analyses suggest that graph isomorphism can easily be solved for many types of graphs and hence is not an ideal solution for implementing ZKP.

Date: December 2009

Creator: Ayeh, Eric

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Flight Control Subsystem

Paper describes a project with the goal of designing and prototyping a small-scale unmanned aerial vehicle (UAV), offering dual-channel real-time video, data logging, and waypoint tracking.

Date: 2010

Creator: Williams, Jennifer; Bratton, David; Jones, Aaron; Anderson, Alyse; Befort, Jonathan; Lowe, Ryan et al.

Item Type: Article

Partner: UNT Libraries

open access

Effective and Accelerated Informative Frame Filtering in Colonoscopy Videos Using Graphic Processing Units

Colonoscopy is an endoscopic technique that allows a physician to inspect the mucosa of the human colon. Previous methods and software solutions to detect informative frames in a colonoscopy video (a process called informative frame filtering or IFF) have been hugely ineffective in (1) covering the proper definition of an informative frame in the broadest sense and (2) striking an optimal balance between accuracy and speed of classification in both real-time and non real-time medical procedure… more

Date: August 2010

Creator: Karri, Venkata Praveen

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Socioscope: Human Relationship and Behavior Analysis in Mobile Social Networks

The widely used mobile phone, as well as its related technologies had opened opportunities for a complete change on how people interact and build relationship across geographic and time considerations. The convenience of instant communication by mobile phones that broke the barrier of space and time is evidently the key motivational point on why such technologies so important in people's life and daily activities. Mobile phones have become the most popular communication tools. Mobile phone tech… more

Date: August 2010

Creator: Zhang, Huiqi

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Design and Implementation of Communication Platform for Autonomous Decentralized Systems

This thesis deals with the decentralized autonomous system, in which individual nodes acting like peers, communicate and participate in collaborative tasks and decision making processes. An experimental test-bed is created using four Garcia robots. The robots act like peers and interact with each other using user datagram protocol (UDP) messages. Each robot continuously monitors for messages coming from other robots and respond accordingly. Each robot broadcasts its location to all the other ro… more

Date: December 2010

Creator: Gottipati, Naga Sravani

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Measuring Vital Signs Using Smart Phones

Smart phones today have become increasingly popular with the general public for its diverse abilities like navigation, social networking, and multimedia facilities to name a few. These phones are equipped with high end processors, high resolution cameras, built-in sensors like accelerometer, orientation-sensor, light-sensor, and much more. According to comScore survey, 25.3% of US adults use smart phones in their daily lives. Motivated by the capability of smart phones and their extensive usage… more

Date: December 2010

Creator: Chandrasekaran, Vikram

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Automatic Extraction of Highlights from a Baseball Video Using HMM and MPEG-7 Descriptors

In today’s fast paced world, as the number of stations of television programming offered is increasing rapidly, time accessible to watch them remains same or decreasing. Sports videos are typically lengthy and they appeal to a massive crowd. Though sports video is lengthy, most of the viewer’s desire to watch specific segments of the video which are fascinating, like a home-run in a baseball or goal in soccer i.e., users prefer to watch highlights to save time. When associated to the entire spa… more

Date: May 2011

Creator: Saudagar, Abdullah Naseer Ahmed

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Kalman Filtering Approach to Optimize OFDM Data Rate

This study is based on applying a non-linear mapping method, here the unscented Kalman filter; to estimate and optimize data rate resulting from the arrival rate having a Poisson distribution in an orthogonal frequency division multiplexing (OFDM) transmission system. OFDM is an emerging multi-carrier modulation scheme. With the growing need for quality of service in wireless communications, it is highly necessary to optimize resources in such a way that the overall performance of the system mo… more

Date: August 2011

Creator: Wunnava, Sashi Prabha

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Scene Analysis Using Scale Invariant Feature Extraction and Probabilistic Modeling

Conventional pattern recognition systems have two components: feature analysis and pattern classification. For any object in an image, features could be considered as the major characteristic of the object either for object recognition or object tracking purpose. Features extracted from a training image, can be used to identify the object when attempting to locate the object in a test image containing many other objects. To perform reliable scene analysis, it is important that the features extr… more

Date: August 2011

Creator: Shen, Yao

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Development of Indium Oxide Nanowires as Efficient Gas Sensors

Crystalline indium oxide nanowires were synthesized following optimization of growth parameters. Oxygen vacancies were found to impact the optical and electronic properties of the as-grown nanowires. Photoluminescence measurements showed a strong U.V emission peak at 3.18 eV and defect peaks in the visible region at 2.85 eV, 2.66 eV and 2.5 eV. The defect peaks are attributed to neutral and charged states of oxygen vacancies. Post-growth annealing in oxygen environment and passivation with sulp… more

Date: December 2011

Creator: Gali, Pradeep

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Development of Silicon Nanowire Field Effect Transistors

An economically reliable technique for the synthesis of silicon nanowire was developed using silicon chloride as source material. The 30-40 micron long nanowires were found to have diameters ranging from 40 – 100 nm. An amorphous oxide shell covered the nanowires, post-growth. Raman spectroscopy confirmed the composition of the shell to be silicon-dioxide. Photoluminescence measurements of the as-grown nanowires showed green emission, attributed to the presence of the oxide shell. Etching of th… more

Date: December 2011

Creator: Nukala, Prathyusha

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Baseband Noise Suppression in Ofdm Using Kalman Filter

As the technology is advances the reduced size of hardware gives rise to an additive 1/f baseband noise. This additive 1/f noise is a system noise generated due to miniaturization of hardware and affects the lower frequencies. Though 1/f noise does not show much effect in wide band channels because of its nature to affect only certain frequencies, 1/f noise becomes a prominent in OFDM communication systems where narrow band channels are used. in this thesis, I study the effects of 1/f noise on … more

Date: May 2012

Creator: Rodda, Lasya

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Incremental Learning with Large Datasets

This dissertation focuses on the novel learning strategy based on geometric support vector machines to address the difficulties of processing immense data set. Support vector machines find the hyper-plane that maximizes the margin between two classes, and the decision boundary is represented with a few training samples it becomes a favorable choice for incremental learning. The dissertation presents a novel method Geometric Incremental Support Vector Machines (GISVMs) to address both efficiency… more

Date: May 2012

Creator: Giritharan, Balathasan

Item Type: Thesis or Dissertation

Partner: UNT Libraries

open access

Multi-perspective, Multi-modal Image Registration and Fusion

Multi-modal image fusion is an active research area with many civilian and military applications. Fusion is defined as strategic combination of information collected by various sensors from different locations or different types in order to obtain a better understanding of an observed scene or situation. Fusion of multi-modal images cannot be completed unless these two modalities are spatially aligned. In this research, I consider two important problems. Multi-modal, multi-perspective image reg… more

Date: August 2012

Creator: Belkhouche, Mohammed Yassine

Item Type: Thesis or Dissertation

Partner: UNT Libraries