Engineering Commons^™

Performance Of Multi-User Codes In Wireless Communications, Muhammad Tauseef Ulislam

Theses

Multi-user codes are a widely used in transmitting user data from base station to mobile station and vice versa. In wireless communications a signal received by a mobile station goes through different fading channels resulting. These multi-paths add constructively and destructively with different delays and attenuation at the mobile station. The autocorrelation and cross correlation properties of the Multi-user codes play a significant role in extracting the user data from the signal corrupted by multipath fading channel.

The thesis presents a comparison of different Multi-user codes based on their autocorrelation and cross correlation properties. These codes are passed through a …

Analysis Of Acceleration And Deceleration During Cyclic Exercise, Jeena Vadi

Theses

The Cyclic Exercise Protocol is a novel protocol that is designed to create a series of cyclic waves of exercise and recovery. This exercise protocol involves short bursts of exercise lasting for 60 seconds or less followed by a period of complete cardio recovery. This study involves the analysis of the acceleration and the deceleration regions of the cyclic exercise sessions. The objective of this study was to develop an algorithm to quantitatively analyze the acceleration and the deceleration regions of cyclic exercise sessions. The acceleration and the deceleration regions of cycles were split into three segments and each segment …

Evaluation Of Knox Group Contribution Parameters Using Quantum Based Molecular And Group Properties, Myriam Carrillo

Theses

Thermodynamic property prediction through the group contribution methods has been improving. However, the approaches considered in the past present not only limitations on the physical basis but often have restrictions as to certain substances, such as isomers. A new group contribution method is proposed that uses AIM theory, which is based on computational chemistry and quantum mechanics, to overcome these limitations by treating each molecule individually. An evaluation of this method as applied to the Knox model is proposed and analyzed for Vapor Liquid Equilibrium (VLE) of mixtures with the help of nine global parameters that are obtained by correlation. …

Study Of Steganalysis Methods, Wen Chen

Theses

Steganography is the art and science of hiding the presence of conmunication by embedding secret message into digital images. The steganographic techniques can be applied in many areas. On one hand, people can benefit from their application. For example, they can be used for copyright protection. On the other hand, these techniques may be used by criminals or terrorists for malicious purposes. For example, terrorists may use the techniques to transmit the secret plan of terror attacks. Law enforcement and security authorities have concerns about such activities. It is necessary to devise the methods to detect steganographic systems. The detection …

Obtaining Optimal Data Length For Fmri Images, Vikram M. Natarajan

Theses

Interest in brain hemodynamics has led to a substantial increase in state of the art research within the field of functional Magnetic Resonance Imaging (fMRI). FMRI enables research to be conducted on brain mapping in healthy individuals, as well as in patient populations. The need for accurate functional images is required. The primary objective was the development of a method to determine the optimal number of time points required to obtain reliable activation maps. The second phase involved the development of a program, which enabled the conversion of functional magnetic resonance images to a format that the neurosurgeon's scanner could …

Scalable Wide Area Ad-Hoc Networking, Nithin Bose

Theses

The scalability problem of routing algorithms in Mobile Ad-hoc networks (MANET) has conventionally been addressed by introducing hierarchical architectures, clusters, and neighborhood zones. In all of these approaches, some nodes are assigned different routing related roles than others. Examples include cluster heads, virtual backbones and border nodes. The selection of these nodes on a fixed or dynamic basis adds complexity to the routing algorithm, in addition to placing significant demands on mobility and power consumption of these nodes. Furthermore, the scalability achieved with hierarchical architectures or partitions is limited.

This thesis demonstrates that location awareness can greatly aid in MANET …

Labview Controlled Study Of The Propagation Properties Of Ultrasound In Synthetic Fog Environment, Aparna Venkataraman

Theses

Diagnostic ultrasound employs pulsed, high frequency sound waves that are reflected back from body tissues and processed by ultrasound receivers to create characteristic images in varied applications such as cardiology, obstetrics and gynecology neurology and urology. Ultrasound intensity is primarily affected by the changes in acoustic impedance of the medium. Literature on ultrasound indicates that the propagation of ultrasound increases gradually as the density increases from air to water. Such studies have been confined to only the three states of matter and have never discussed a fog medium.

The primary objective of this thesis study was to design a system …

An Autonomous Router-Based Solution To Detect And Defend Low Rate Ddos Attacks, Karunakar Anantharam

Theses

Internet security was not a concern when the Internet was invented, but we cannot deny this fact anymore. Since all forms of businesses and communications are aligned to the Internet in one form or the other, the security of these assets (both infrastructure and content) is of prime importance. Some of the well known consequences of an attack include gaining access to a network, intellectual property thefts, and denial of service.

This thesis focuses on countering flood-type attacks that result in denial of service to end users. A new classification of this denial of service attacks, known as the low …

A Co-Processor Design To Support Mpi Primitives In Configurable Multiprocessor Designs, Rohan Bafna

Theses

The Message-Passing Interface (MIPI) is a widely used standard for inter-processor communication in parallel computers. This standard is normally implemented in software, thus resulting in large communication latencies. A hardware implementation can reduce communication latencies significantly, thereby increasing the bandwidth. However, this approach cannot be applied in practice to the very large set of functions in MPI.

Reconfigurable computing has reached levels where entire parallel systems can be built inside one or more FPGAs (Field-Programmable Gate Arrays). In this scheme, specialized components must be built for inter-processor communication and the resulting code is difficult to port to other reconfigurable platforms. …

Cyclic Prefix Assisted Block Transmission For Low Complexity Communication System Design, Haibin Huang

Theses

This thesis presents new results on cyclic prefix (CP) assisted block transmission for low complexity communication system design. Two important aspects are studied: the CP based low-complexity schemes for channel equalization and channel estimation.

Specifically, based on the simple frequency domain equalization, a low complexity joint receiver is proposed for CP-CDMA system, which is a special application of block transmission.

And in this work the finite impulse response (FIR) model is used for the unknown communication channels. To identify an unknown FIR channel, a novel channel estimation method is proposed by exploiting the cyclic prefix technique. Compared to a conventional …

Parameter Based Synthesis Of Sign Language, Amanda Irving

Theses

The primary objective of this project is to demonstrate synthesis of signs in American Sign Language with a finite number of parameters. The parameters in this method include 22 key locations, six location modifiers, six orientation indicators, 46 hand shapes, six predefined movements and seven possible end effectors. These parameters can be used in conjunction with a computer script and they maximize precision and versatility while minimizing development time and resources. The parameters for each sign are stored in an individual text file averaging approximately half a kilobyte.

The success of this project is demonstrated using UGS's Jack Software, Version …

A Digital Signature And Watermarking Based Authentication System For Jpeg2000 Images, Rui Jing

Theses

In this thesis, digital signature based authentication system was introduced, which is able to protect JPEG2000 images in different flavors, including fragile authentication and semi-fragile authentication. The fragile authentication is to protect the image at code-stream level, and the semi-fragile is to protect the image at the content level.

The semi-fragile can be further classified into lossy and lossless authentication. With lossless authentication, the original image can be recovered after verification. The lossless authentication and the new image compression standard, JPEG2000 is mainly discussed in this thesis.

Optical Properties Of Sige Nanostructures, Varun Sharma

Theses

In this thesis, Raman Scattering (RS) and photoluminescence (PL) measurements of Ge nanowires (NWs) grown via vapor-liquid-solid (VLS) using chemical vapor deposition silicon substrates consisting of (100) and (111) crystallographic orientations are reported. Ge NWs grown are ~40 nm in diameter, approximately a micrometer in length, and a sharp narrow Raman peak at ~300cm^-1 indicates single crystal quality. An absence of SiGe peak in the Raman spectra indicates that SiGe interdiffusion is insignificant for the NW volume. Low temperature PL-intensity-dependence spectra indicate that the observed emission originates at the Ge NW - Si substrate interface, where SiGe intermixing has …

Study Of Joint Embedding And Compression On Jpeg Compression Scheme Using Multiple Codebook Data Hiding, Amol Nishikant Sukerkar

Theses

This thesis studies a direct application of multiple codebook data hiding technique in the multimedia applications. It studies the practical implementation of a joint embedding and compression scheme. It presents a study of Type III data embedding technique using multiple codebook design on JPEG-85 compression scheme. The application of the above technique is compared with the Type III data embedding techniques using single codebook design. The comparison is carried out in tenns of the parameters such as mean square error and normalized correlation between the embedded and extracted watermark.

The performance of data hiding rate against the embedding distortion is …

Ambulatory Measurement Of Body Position, Swetha Vennamaneni

Theses

Ambulatory monitoring is playing an important role in the clinical and research field. In the modem era, physicians are showing much interest in measuring heart rate, blood pressure and many other physical and cardiac conditions and recording electrocardiogram (ECG, a popular technique for diagnosing heart related disease), while the patient is ambulatory. Heart rate, blood pressure and ECG waveform can change because of body position. In the case of the ECG, the changes caused by body position are can change the ST-T segment and also the QRS amplitude. The heart rate and blood pressure changes when there is a change …

Electrospinning Of Biphasic Biopolymer And Polymer : A Feasibility And Characterization Study, Sherry Hsiu-Ying Wang

Theses

Electrospinning of polymeric materials have been experimented to achieve nanoscaled diameters. The approaches to the current study are to combine a natural material such as collagen with synthetic materials and determine if the interactions between the materials can be used in the electrospinning process. Collagen is a material of choice due to its biocompatibility. When collagen is combined with polymer, Polyethylene Oxide (PEG), the fiber diameters ranged from 150nm to one micron. The fibers produced have shown drastic phase separation. The next study involved using a duel solvent system to electrospin fibers. The polymer of choice is Poly (1-lactic acid) …

Heat Transfer Model For The Ignition Of Metal Powder On A Heated Filament, Trent Stanton Ward

Theses

The thermal processes leading to ignition of metal powders in environments that experience rapid temperature changes are currently poorly understood. In this research, a methodology for studying and quantification of such processes is developed. In the experimental case study, the ignition temperature of Mg powder coated on the surface of an electrically heated filament is detected optically at different heating rates. To interpret the results, a heat transfer model has been developed for a multilayer powder coating on top of an electrically heated filament. The coating is modeled using a hexagonal close packed geometry and the heat transfer equations are …