Engineering Commons^™

Probabilistic Analysis Of Defect Tolerance In Asynchronous Nano Crossbar Architecture, Shikha Chaudhary

Masters Theses

"Among recent advancements in technology, nanotechnology is particularly promising. Most researchers have begun to focus their efforts on developing nano scale circuits. Nano scale devices such as carbon nano tubes (CNT) and silicon nano wires (SiNW) form the primitive building blocks of many nano scale logic devices and recently developed computing architecture. One of the most promising nanotechnologies is crossbar-based architecture, a two-dimensional nanoarray, formed by the intersection of two orthogonal sets of parallel and uniformly-spaced CNTs or SiNWs. Nanowire crossbars offer the potential for ultra-high density, which has never been achieved by photolithography. In an effort to improve these …

Metadata And Data Management In High Performance File And Storage Systems, Peng Gu

Electronic Theses and Dissertations

With the advent of emerging "e-Science" applications, today's scientific research increasingly relies on petascale-and-beyond computing over large data sets of the same magnitude. While the computational power of supercomputers has recently entered the era of petascale, the performance of their storage system is far lagged behind by many orders of magnitude. This places an imperative demand on revolutionizing their underlying I/O systems, on which the management of both metadata and data is deemed to have significant performance implications. Prefetching/caching and data locality awareness optimizations, as conventional and effective management techniques for metadata and data I/O performance enhancement, still play their …

Delay Sensitive Routing For Real Time Traffic Over Ad-Hoc Networks, Dipika Darshana

Electronic Theses and Dissertations

Wireless ad hoc network consists of inexpensive nodes that form a mobile communication network. Due to limitations of the transmission range, the nodes rely on each other to forward packets such that messages can be delivered across the network. The selection of the path along which a packet is forwarded from the source node to the destination node is done by the routing algorithm. Most commonly used routing algorithms, though effective for non-real time applications, cannot handle real-time applications that require strict delay bounds on packet delivery. In this thesis, we propose a routing protocol that ensures timely delivery of …

Optimization In Multi-Agent Systems : Structures And Procedures, Ingo Stengel

Theses

The main advantage for the use of agent technology is in the capacity of agents to represent the interests of individual entities and to act autonomously on their behalf. In multi-agent systems this involves communication, coordination and negotiation.

The focus of this dissertation is to find ways to optimize multi-agent systems at different levels by taking into consideration their structure and the procedures used. As optimization depends to a large extent on the problem to be solved, group forming scenarios, in which self-interested agents compete to form and join groups, have been selected here for consideration. Optimization issues are discussed …

Extracting, Representing And Mining Semantic Metadata From Text: Facilitating Knowledge Discovery In Biomedicine, Cartic Ramakrishnan

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The information access paradigm offered by most contemporary text information systems is a search-and-sift paradigm where users have to manually glean and aggregate relevant information from the large number of documents that are typically returned in response to keyword queries. Expecting the users to glean and aggregate information has lead to several inadequacies in these information systems. Owing to the size of many text databases, search-and-sift is a very tedious often requiring repeated keyword searches refining or generalizing queries terms. A more serious limitation arises from the lack of automated mechanisms to aggregate content across different documents to discover new …

Two Dimensional Localization Of Passive Uhf Rfid Tags, Bhavik Contractor

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The advent of GPS has redefined the need of a positioning system in today*#8217;s ubiquitous computing world. While GPS works satisfactorily and is quite a norm in an outdoor environment, it fails to work indoors due to the inherent complexity of an indoor environment. There is an ever increasing need to develop an indoor positioning system and a lot of research has been done to solve the problem of indoor localization. These solutions differ on the basis of cost, dependency on environment, line of sight requirements and so on.

Passive RFID (Radio Frequency Identification) tags pose an interesting solution to …

A Framework To Support Spatial, Temporal And Thematic Analytics Over Semantic Web Data, Matthew Steven Perry

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Spatial and temporal data are critical components in many applications. This is especially true in analytical applications ranging from scientific discovery to national security and criminal investigation. The analytical process often requires uncovering and analyzing complex thematic relationships between disparate people, places and events. Fundamentally new query operators based on the graph structure of Semantic Web data models, such as semantic associations, are proving useful for this purpose. However, these analysis mechanisms are primarily intended for thematic relationships. This dissertation proposes a framework built around the RDF data model for analysis of thematic, spatial and temporal relationships between named entities. …

Evolutionary Methodology For Optimization Of Image Transforms Subject To Quantization Noise, Michael Ray Peterson

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Lossy image compression algorithms sacrifice perfect imagereconstruction in favor of decreased storage requirements. Modelossy compression schemes, such as JPEG2000, rely upon the discrete wavelet transform (DWT) to achieve high levels of compression while minimizing the loss of information for image reconstruction. Some compression applications require higher levels of compression than those achieved through application of the DWT and entropy coding. In such lossy systems, quantization provides high compression rates at the cost of increased distortion. Unfortunately, as the amount of quantization increases, the performance of the DWT for accurate image reconstruction deteriorates. Previous research demonstrates that a genetic algorithm can …

Algorithmic Techniques Employed In The Isolation Of Codon Usage Biases In Prokaryotic Genomes, Douglas W. Raiford Iii

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While genomic sequencing projects are an abundant source of information for biological studies ranging from the molecular to the ecological in scale, much of the information present may yet be hidden from casual analysis. One such information domain, trends in codon usage, can provide a wealth of information about an organism's genes and their expression. Degeneracy in the genetic code allows more than one triplet codon to code for the same amino acid, and usage of these codons is often biased such that one or more of these synonymous codons is preferred. Isolation of translational efficiency bias can have important …

Energy Efficient Image Video Sensor Networks, Paul Anthony Bender

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Image Video Sensor Networks are emerging applications for sensor network technologies. The relatively large size of the data collected by image video sensors presents new challenges for the sensor network in terms of energy consumption and channel capacity. We address each of these issues through the use of a high density network deployment utilizing some nodes as dedicated relay nodes.

A high density network allows network nodes to reduce their transmission power. This reduction in transmission power allows each node to conserve power and simultaneously increases the potential for spatially concurrent transmissions within the network, resulting in improved network throughputs. …

Transformation Of Object-Oriented Associations And Embedded References To Them, Sneha Swamy

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AFIT Wide Spectrum Object Modeling Environment (AWSOME) automatically generates executable code by applying transforms to the formal specifications developed from the domain knowledge. AWSOME uses the specification language called as AFIT Wide Spectrum Language (AWL). All the transforms developed for AWSOME depend on and manipulate Abstract Syntax Trees (ASTs) created by parsing the formal specifications of a model. The main idea is to speed the process of creating error free code, to aid reusability of code and also to make the maintenance changes to be consistent and correct. The AWSOME metamodel contains the structural (object) model, the functional (operations) model …

A Meta Analysis Of Critical Success Factors For Computer Technology Projects, Ross A. Baker

Theses

Project managers are continually in pursuit of a magic formula that will deliver a successful project. Companies arc interested in formulas for project success because billions of dollars arc wasted each year, in U.S.A. Information Technology projects alone. through poorly managed or failed projects. Failing projects arc not only bad for the individual project team members, but a failed project's impacts emanate outward to cause companies to decline or die. In addition, the targeted customers who receive inferior products, late products, or no products at all (due to project failures) are significantly impacted as well. Because failed computer technology projects …

Defect-Tolerance And Testing For Configurable Nano-Crossbars, Mandar V. Joshi

Masters Theses

"Moore's Law speculated a trend in computation technology in terms of number of transistors per unit area that would double roughly every two years. Even after 40 years of this prediction, current technologies have been following it successfully. There are however, certain physical limitations of current CMOS that would result in fundamental obstructions to continuation of Moore's Law. Although there is a debate amongst experts on how much time it would take for this to happen, it is certain that some entirely new paradigms for semiconductor electronics would be needed to replace CMOS and to delay the end of Moore's …