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Full-Text Articles in Engineering

Simulating A Universal Geocast Scheme For Vehicular Ad Hoc Networks, Benjamin L. Bovee Jan 2011

Simulating A Universal Geocast Scheme For Vehicular Ad Hoc Networks, Benjamin L. Bovee

Masters Theses 1911 - February 2014

Recently a number of communications schemes have been proposed for Vehicular Ad hoc Networks (VANETs). One of these, the Universal Geocast Scheme (UGS) proposed by Hossein Pishro-Nik and Mohammad Nekoui, provides for a diverse variety of VANET-specific characteristics such as time-varying topology, protocol variation based on road congestion, and support for non line-of-sight communication. In this research, the UGS protocol is extended to consider inter-vehicle multi-hop connections in intersections with surrounding obstructions along with single-hop communications in an open road scenario. Since UGS is a probabilistic, repetition-based scheme, it supports the capacity-delay tradeoffs crucial for periodic safety message exchange. The …


Addressing/Exploiting Transceiver Imperfections In Wireless Communication Systems, Lihao Wang Jan 2011

Addressing/Exploiting Transceiver Imperfections In Wireless Communication Systems, Lihao Wang

Masters Theses 1911 - February 2014

This thesis consists of two research projects on wireless communication systems. In the first project, we propose a fast inphase and quadrature (I/Q) imbalance compensation technique for the analog quadrature modulators in direct conversion transmitters. The method needs no training sequence, no extra background data gathering process and no prior perfect knowledge of the envelope detector characteristics. In contrast to previous approaches, it uses points from both the linear and predictable nonlinear regions of the envelope detector to hasten convergence. We provide a least mean square (LMS) version and demonstrate that the quadrature modulator compensator converges.

In the second project, …


A Real Time Web Based Electronic Triage, Resource Allocation And Hospital Dispatch System For Emergency Response, Venkata Srihari Inampudi Jan 2011

A Real Time Web Based Electronic Triage, Resource Allocation And Hospital Dispatch System For Emergency Response, Venkata Srihari Inampudi

Masters Theses 1911 - February 2014

Disasters are characterized by large numbers of victims and required resources, overwhelming the available resources. Disaster response involves various entities like Incident Commanders, dispatch centers, emergency operations centers, area command and hospitals. An effective emergency response system should facilitate coordination between these various entities. Victim triage, emergency resource allocation and victim dispatch to hospitals form an important part of an emergency response system. In this present research effort, an emergency response system with the aforementioned components is developed.

Triage is the process of prioritizing mass casualty victims based on severity of injuries. The system presented in this thesis is a …


Parallel Mesh Adaptation And Graph Analysis Using Graphics Processing Units, Timothy P. Mcguiness Jan 2011

Parallel Mesh Adaptation And Graph Analysis Using Graphics Processing Units, Timothy P. Mcguiness

Masters Theses 1911 - February 2014

In the field of Computational Fluid Dynamics, several types of mesh adaptation strategies are used to enhance a mesh’s quality, thereby improving simulation speed and accuracy. Mesh smoothing (r-refinement) is a simple and effective technique, where nodes are repositioned to increase or decrease local mesh resolution. Mesh partitioning divides a mesh into sections, for use on distributed-memory parallel machines. As a more abstract form of modeling, graph theory can be used to simulate many real-world problems, and has applications in the fields of computer science, sociology, engineering and transportation, to name a few. One of the more important graph analysis …


Leveraging Multi-Radio Communication For Mobile Wireless Sensor Networks, Jeremy J. Gummeson Jan 2011

Leveraging Multi-Radio Communication For Mobile Wireless Sensor Networks, Jeremy J. Gummeson

Masters Theses 1911 - February 2014

An important challenge in mobile sensor networks is to enable energy-efficient communication over a diversity of distances while being robust to wireless effects caused by node mobility. In this thesis, we argue that the pairing of two complementary radios with heterogeneous range characteristics enables greater range and interference diversity at lower energy cost than a single radio. We make three contributions towards the design of such multi-radio mobile sensor systems. First, we present the design of a novel reinforcement learning-based link layer algorithm that continually learns channel characteristics and dynamically decides when to switch between radios. Second, we describe a …


Hardware Implementation Of Queue Length Based Pacing On Netfpga, Abhishek Dwaraki Jan 2011

Hardware Implementation Of Queue Length Based Pacing On Netfpga, Abhishek Dwaraki

Masters Theses 1911 - February 2014

Optical packet switching networks are the foundation for next generation high speed Internet and are fast becoming the norm rather than an option. When such high speed optical networks are taken into account, one of the key considerations is packet buffering. The importance of packet buffering plays an even bigger role in optical networks because of the physical and technological constraints on the buffer sizes that can be implemented. Existing protocols, in many real world scenarios do not perform well in such networks. To eliminate such scenarios where there is a high possibility of packet loss, we use packet pacing. …


A Real Time Indoor Navigation And Monitoring System For Firefighters And Visually Impaired, Siddhesh R. Gandhi Jan 2011

A Real Time Indoor Navigation And Monitoring System For Firefighters And Visually Impaired, Siddhesh R. Gandhi

Masters Theses 1911 - February 2014

ABSTRACT

A REAL TIME INDOOR NAVIGATION AND MONITORING SYSTEM FOR FIREFIGHTERS AND VISUALLY IMPAIRED

MAY 2011

SIDDHESH RAJAN GANDHI

M.S. E.C.E, UNIVERSITY OF MASSACHUSETTS AMHERST

Directed by: Professor Aura Ganz

There has been a widespread growth of technology in almost every facet of day to day life. But there are still important application areas in which technology advancements have not been implemented in a cost effective and user friendly manner. Such applications which we will address in this proposal include: 1) indoor localization and navigation of firefighters during rescue operations and 2) indoor localization and navigation for the blind and …