Engineering Commons^™

The Design Of Medium Access Control (Mac) Protocols For Energy Efficient And Qos Provision In Wireless Sensor Networks, Yang Liu

Masters Theses

This thesis work focuses on innovative design of media access control (MAC) protocols in wireless sensor networks (WNSs). The characteristics of the WSN inquire that the network service design considers both energy efficiency and the associated application requirement. However, most existing protocols address only the issue of energy efficiency.

In this thesis, a MAC protocol has been proposed (referred to as Q-MAC) that not only minimized the energy consumption in multi-hop WSNs, but also provides Quality of Service (QoS) by differentiating network services based on priority levels prescribed by different applications. The priority levels reflect the state of system resources …

Curvature Variation As Measure Of Shape Information, Sreenivas Rangan Sukumar

Masters Theses

In this thesis, we present the Curvature Variation Measure (CVM) as our informational approach to shape description. We base our algorithm on shape curvature, and extract shape information as the entropic measure of the curvature. We present definitions to estimate curvature for both discrete 2D curves and 3D surfaces and then formulate our theory of shape information from these definitions.

With focus on reverse engineering and under vehicle inspection, we document our research efforts in constructing a scanning mechanism to model real world objects. We use a laser-based range sensor for the data collection and discuss view-fusion and integration to …

A Characteristic Study Of The Atmospheric Pressure Nonthermal Resistive Barrier Plasma Discharge For Biological Decontamination, Magesh Thiyagarajan

Masters Theses

Steady-state atmospheric pressure nonthermal plasmas can splendidly debilitate bacteria in liquids, gases and on surfaces, as well as can disintegrate hazardous chemicals. The nonthermal gas discharge at atmospheric pressure, such as resistive barrier discharge is investigated for low temperature sterilization purposes. In specific, exploring and understanding the hidden secrets of the plasma sterilization mechanisms and the intensification of the main microbial reduction pathways are the objectives of the research.

A dual-mode steady-state atmospheric pressure resistive barrier ionized gas (plasma) generator has been designed and developed to meet the environmental health and federally mandated safety standards. Electrical, chemical, optical, and biological …

An Experimental Model Of Ball Lightning, Madras Parameswaran Sriram

Masters Theses

A form of ball lightning was generated in the laboratory. Plasma spheres several centimeters in diameter were produced in atmospheric pressure air. These spheres persisted up to ½ a second after power turn –off. A mathematical model was derived that predicts the observed lifetime. The theory predicts that the sphere lifetime should scale as the radius squared, which means large spheres should exist for many seconds. We also generated ball lightning in a zero gravity environment. The object was to eliminate convection, which had been observed to reduce the size of a ball generated by a two – dimensional electric …

A 1.8 Ghz Lc-Voltage Controlled Oscillator Using On-Chip Inductors And Body Driven Varactors In Cmos 0.35 Μm Process, Lakshmipriya Seshan

Masters Theses

In an era dominated by the highly demanding wireless communication system, there is a great need for developing small, cheap, and low power RF sub-systems. This demand has lead to significant research on completely integrated transceiver systems. One of the great challenges in an integrated transceiver system is the frequency synthesizer. Frequency synthesizers are usually implemented using a phase locked loop (PLL) and low frequency highly stable crystal oscillator. The spectral purity of a synthesized carrier signal depends on the kind of Voltage Controlled Oscillator (VCO) used. Hence successful implementation of a low phase noise, completely integrated VCO in standard …

Eliminating Harmonics In A Cascaded H-Bridges Multilevel Inverter Using Resultant Theory, Symmetric Polynomials, And Power Sums, Keith Jeremy Mckenzie

Masters Theses

This thesis studies a multilevel converter with assumed equal dc sources. The multilevel fundamental switching scheme is used to control the needed power electronics switches. Also, a method is presented where switching angles are computed such that a desired fundamental sinusoidal voltage is produced while at the same time certain higher order harmonics are eliminated.

Using Fourier Series theory, the transcendental equations eliminating certain higher order harmonics were derived in terms of the switching angles. Furthermore, these transcendental equations were transformed into polynomial equations by making some simple changes of variables. Resultant theory was used to solve the polynomial equations. …