Engineering Commons^™

Modifying Instruction Sets In The Gem5 Simulator To Support Fault Tolerant Designs, Chuan Zhang

Masters Theses

Traditional fault tolerant techniques such as hardware or time redundancy incur high overhead and are inefficient for checking arithmetic operations. Our objective is to study an alternative approach of adding new instructions to check arithmetic operations. These checking instructions either rely on error detecting code or calculate approximate results and consequently, consume much less execution time. To evaluate the effectiveness of such an approach we wish to modify several benchmarks to use checking instructions and run simulation experiments to find out their execution time and memory usage. However, the checking instructions are not included in the instruction set and as …

User Interface Design And Forensic Analysis For Diorama, Decision Support System For Mass Casualty Incidents, Jun Yi

Masters Theses

In this thesis we introduces the user interface design and forensic analysis tool for DIORAMA system. With an Android device, DIORAMA provides emergency personnel the ability to collect information in real time, track the resources and manage them. It allows the responders and commanders to mange multiple incidents simultaneously. This thesis also describes the implementations of commander app and responder app, as well as two different communication strategies used in DIORAMA. Several trials and simulated mass casualty incidents were conducted to test the functionalities and performance of DIORAMA system. All responders that participated in all trials were very satisfied with …

Indoor And Outdoor Real Time Information Collection In Disaster Scenario, Dongyi Yang

Masters Theses

A disaster usually severely harms human health and property. After a disaster, great amount of information of a disaster area is needed urgently. The information not only indicates the severity of the disaster, but also is crucial for an efficient search and rescue process. In order to quickly and accurately collect real time information in a disaster scenario, a mobile platform is developed for an outdoor scenario and a localization and navigation system for responders is introduced for an indoor scenario.

The mobile platform has been integrated to the DIORAMA system. It is built with a 6-wheel robot chassis along …

Towards A Semantic Knowledge Management Framework For Laminated Composites, Vivek Premkumar

Masters Theses

The engineering of laminated composite structures is a complex task for design engineers and manufacturers, requiring significant management of manufacturing process and materials information. Ontologies are becoming increasingly commonplace for semantically representing knowledge in a formal manner that facilitates sharing of rich information between people and applications. Moreover, ontologies can support first-order logic and reasoning by rule engines that enhance automation. To support the engineering of laminated composite structures, this work developed a novel Semantic LAminated Composites Knowledge management System (SLACKS) that is based on a suite of ontologies for laminated composites materials and design for manufacturing (DFM) and their …

Promoting Extracellular Matrix Crosslinking In Synthetic Hydrogels, Marcos M. Manganare

Masters Theses

The extracellular matrix (ECM) provides mechanical and biochemical support to tissues and cells. It is crucial for cell attachment, differentiation, and migration, as well as for ailment-associated processes such as angiogenesis, metastases and cancer development. An approach to study these phenomena is through emulation of the ECM by synthetic gels constructed of natural polymers, such as collagen and fibronectin, or simple but tunable materials such as poly(ethylene glycol) (PEG) crosslinked with short peptide sequences susceptible to digestion by metalloproteases and cell-binding domains. Our lab uses PEG gels to study cell behavior in three dimensions (3D). Although this system fosters cell …

Evaluation Of A Training Program (Strap) Designed To Decrease Young Drivers Secondary Task Engagement In High Risk Scenarios, Akhilesh Krishnan

Masters Theses

Distracted driving involving secondary tasks is known to lead to an increased likelihood of being involved in motor vehicle crashes. Some secondary tasks are unnecessary and should never be performed. But other secondary tasks, e.g., operating the defroster, are critical to safe driving. Ideally, the driver should schedule when to perform the critical tasks such that the likelihood of a hazard materializing is relatively small during the performance of the secondary task. The current study evaluates a training program -- STRAP (Secondary Task Regulatory & Anticipatory Program) -- which is designed to make drivers aware of latent hazards …

A Real-Time Signal Control System To Minimize Emissions At Isolated Intersections, Farnoush Khalighi

Masters Theses

Continuous transportation demand growth in recent years has led to many traffic issues in urban areas. Among the most challenging ones are traffic congestion and the associated vehicular emissions. Efficient design of traffic signal control systems can be a promising approach to address these problems. This research develops a real-time signal control system, which optimizes signal timings at an under-saturated isolated intersection by minimizing total vehicular emissions. A combination of previously introduced analytical models based on traffic flow theory has been used. These models are able to estimate time spent per driving mode (i.e., time spent accelerating, decelerating, cruising, and …

Development Of Prototypes Of A Portable Road Weather Information System, Meha Kainth

Masters Theses

Weather conditions have significant impact on road safety and roadway maintenance operations. Road Weather Information Systems (RWIS) play a significant role in providing weather and surface conditions to transportation agencies to monitor weather events. Fixed installations of RWIS are used for weather and pavement surface monitoring. However, permanent fixture installations may not be feasible due to reasons such as cost, accessibility to the site, siting concerns, and terrain. Portable RWIS provide a cost-effective solution in areas where permanent weather station installation is not possible. This study discusses use and benefits of the portable RWIS and outlines the issues involved in …

Design And Implementation Of A High Performance Network Processor With Dynamic Workload Management, Padmaja Duggisetty

Masters Theses

Internet plays a crucial part in today's world. Be it personal communication, business transactions or social networking, internet is used everywhere and hence the speed of the communication infrastructure plays an important role. As the number of users increase the network usage increases i.e., the network data rates ramped up from a few Mb/s to Gb/s in less than a decade. Hence the network infrastructure needed a major upgrade to be able to support such high data rates. Technological advancements have enabled the communication links like optical fibres to support these high bandwidths, but the processing speed at the nodes …

Application Of Techniques For Map Estimation To Distributed Constraint Optimization Problem, Yoonheui Kim

Doctoral Dissertations

The problem of efficiently finding near-optimal decisions in multi-agent systems has become increasingly important because of the growing number of multi-agent applications with large numbers of agents operating in real-world environments. In these systems, agents are often subject to tight resource constraints and agents have only local views. When agents have non-global constraints, each of which is independent, the problem can be formalized as a distributed constraint optimization problem (DCOP). The DCOP is closely associated with the problem of inference on graphical models. Many approaches from inference literature have been adopted to solve DCOPs. We focus on the Max-Sum algorithm …

Multi-Scale Characterization And Engineering Of Taxus Suspension Cultures, Sarah A. Wilson

Doctoral Dissertations

Plants produce a diversity of natural products that have commercial applications as flavorings, fragrances, pesticides and pharmaceuticals. These compounds are often the result of specialized metabolic pathways that are unique to plant systems, and have complex structures that make chemical synthesis routes infeasible. This necessitates exploitation of biological production routes. This thesis work presents a multi-scale characterization and engineering approach to understand and manipulate plant cell cultures on the extracellular (culture) and intracellular (metabolic pathway) levels. Studies focus on the commercially relevant suspension culture system Taxus, a medicinal plant species used for production of the FDA-approved anticancer drug paclitaxel. …

Soil-Structure Modeling And Design Considerations For Offshore Wind Turbine Monopile Foundations, Wystan Carswell

Doctoral Dissertations

Offshore wind turbine (OWT) support structures account for 20-25% of the capital cost for offshore wind installations, making it essential to optimize the design of the tower, substructure, and foundation to the extent possible. This dissertation focuses on monopile foundations, as the vast majority (approximately 75%) of currently installed OWTs are supported by monopile structures. The objective of this dissertation is to provide information on the behavior of monopile support structures to better substantiate design and planning decisions and to provide a basis for reducing the structural material costs. In pursuit of these objectives, research is presented on the topics …

Evaluation Of Ferrate Preoxidation For Drinking Water Treatment, Joseph E. Goodwill

Doctoral Dissertations

Ferrate (Fe(IV)) has been proposed as a viable alternative for pre-oxidation in drinking water treatment (Jiang & Lloyd, 2002; Sharma, Kazama, Jiangyong, & Ray, 2005). The primary advantages of ferrate include a strong oxidation potential without the formation of halogenated by-products. In addition, the by-product of ferrate oxidation, ferric iron (Fe(III)), may have beneficial impacts on downstream particle destabilization and removal processes. Also, ferrate has disinfectant properties and may also provide pathogen inactivation in drinking water (Sharma et al., 2005). However, despite these advantages, there is a dearth of research experience that examines the implications of using ferrate for treating …

Privacy-Preserving Payments For Transportation Systems, Gesine Hinterwalder

Doctoral Dissertations

The operation of our society heavily relies on high mobility of people. Not only our social life but also our economy and trade are built upon a system where people need to be able to move around easily. The costs for building and maintaining a suitable transportation infrastructure to satisfy those needs are high, and to charge users is thus a central requirement. This calls for well functioning payment systems satisfying the multitude of requirements that transportation systems impose on them. Electronic payment systems have many benefits over traditional cash payments as they are easy to maintain, can be more …

Skybridge: A New Nanoscale 3-D Computing Framework For Future Integrated Circuits, Mostafizur Rahman

Doctoral Dissertations

Continuous scaling of CMOS has been the major catalyst in miniaturization of integrated circuits (ICs) and crucial for global socio-economic progress. However, continuing the traditional way of scaling to sub-20nm technologies is proving to be very difficult as MOSFETs are reaching their fundamental performance limits [1] and interconnection bottleneck is dominating IC operational power and performance [2]. Migrating to 3-D, as a way to advance scaling, has been elusive due to inherent customization and manufacturing requirements in CMOS architecture that are incompatible with 3-D organization. Partial attempts with die-die [3] and layer-layer [4] stacking have their own limitations [5]. We …

On Thermal Sensor Calibration And Software Techniques For Many-Core Thermal Management, Shiting Lu

Doctoral Dissertations

The high power density of a many-core processor results in increased temperature which negatively impacts system reliability and performance. Dynamic thermal management applies thermal-aware techniques at run time to avoid overheating using temperature information collected from on-chip thermal sensors. Temperature sensing and thermal control schemes are two critical technologies for successfully maintaining thermal safety. In this dissertation, on-line thermal sensor calibration schemes are developed to provide accurate temperature information. Software-based dynamic thermal management techniques are proposed using calibrated thermal sensors. Due to process variation and silicon aging, on-chip thermal sensors require periodic calibration before use in DTM. However, the calibration …

Securing Network Processors With Hardware Monitors, Kekai Hu

Doctoral Dissertations

As an essential part of modern society, the Internet has fundamentally changed our lives during the last decade. Novel applications and technologies, such as online shopping, social networking, cloud computing, mobile networking, etc, have sprung up at an astonishing pace. These technologies not only influence modern life styles but also impact Internet infrastructure. Numerous new network applications and services require better programmability and flexibility for network devices, such as routers and switches. Since traditional fixed function network routers based on application specific integrated circuits (ASICs) have difficulty keeping pace with the growing demands of next-generation Internet applications, there is an …

Modeling The Self-Assembly Of Ordered Nanoporous Materials, Szu-Chia Chien

Doctoral Dissertations

Porous materials are of great importance in many fields due to their wide applications. An ongoing theme in this area is the tailoring of materials for specific applications. With a better understanding of the formation mechanisms, tailoring and controlling the pore structure may be achieved. The objective of this research is acquiring further understanding of the fundamental physics that govern the formation of these materials using molecular simulations. We are aiming to unravel the assembly process of silica porous materials using a semi-rigid silica tetrahedral model. This model together with reaction ensemble Monte Carlo simulations allows us to study the …

An Analysis Of Partial-Depth, Floating, Impermeable Guidance Structures For Downstream Fish Passage At Hydroelectric Facilities, Kevin Mulligan

Doctoral Dissertations

Partial-depth, impermeable guidance structures (or guide walls) are used to enhance downstream passage effectiveness at a hydroelectric facility by actively guiding fish to a safe passage route (i.e. the bypass). Guide walls have been installed in a variety of ways and, like many fish passage devices, have resulted in variable efficiency rates. Currently, the most common type of installment is a steel panel guide wall attached to a floating boom. While less utilized than other guidance structure options (e.g. louvers and bar racks), guide walls have been gaining popularity, particularly within the Northwest United States. The aim of this dissertation …

Energy Optimizations For Smart Buildings And Smart Grids, Aditya K. Mishra

Doctoral Dissertations

Modern buildings are heavy power consumers. For instance, of the total electricity consumed in the US, 75% is consumed in the residential and commercial buildings. This consumption is not evenly distributed over time. Typical consumption profile exhibits several peaks and troughs. The peakiness, in turn, dictates the electric grid's generation, transmission and distribution costs, and also the associated carbon emissions. This thesis discusses challenges involved in achieving the sustainability goals in buildings and electric grids. It investigates building and grid energy footprint optimization techniques to achieve the following goals: 1) making buildings energy efficient, 2) cutting building's electricity bills, 3) …

Virtual Antennas Using Metamaterials, Caglar D. Emiroglu

Doctoral Dissertations

Virtual antenna radiation at microwave frequencies using metamaterials is presented. Based on the transformation electromagnetics technique, the media embedding a physical antenna in a ground recess is designed such that the far-zone radiation pattern of a virtual antenna radiating above a flat conducting ground plane is reproduced. The antenna and a limited surrounding space above a ground plane is folded below the ground level, resulting in a physical antenna in a ground recess that is enclosed in transformation media. The electromagnetic specification of the media surrounding the physical antenna at the bottom of the recess is provided by a properly …

Design And Implementation Of An Economy Plane For The Internet, Xinming Chen

Doctoral Dissertations

The Internet has been very successful in supporting many network applications. As the diversity of uses for the Internet has increased, many protocols and services have been developed by the industry and the research community. However, many of them failed to get deployed in the Internet. One challenge of deploying these novel ideas in operational network is that the network providers need to be involved in the process. Many novel network protocols and services, like multicast and end-to-end QoS, need the support from network providers. However, since network providers are typically driven by business reasons, if they can not get …

Energy-Efficient Content Delivery Networks, Vimal Mathew

Doctoral Dissertations

Internet-scale distributed systems such as content delivery networks (CDNs) operate hundreds of thousands of servers deployed in thousands of data center locations around the globe. Since the energy costs of operating such a large IT infrastructure are a significant fraction of the total operating costs, we argue for redesigning them to incorporate energy optimization as a first-order principle. We focus on CDNs and demonstrate techniques to save energy while meeting client-perceived service level agreements (SLAs) and minimizing impact on hardware reliability. Servers deployed at individual data centers can be switched off at low load to save energy. We show that …

Wind Power Capacity Value Metrics And Variability: A Study In New England, Frederick W. Letson

Doctoral Dissertations

Capacity value is the contribution of a power plant to the ability of the power system to meet high demand. As wind power penetration in New England, and worldwide, increases so does the importance of identifying the capacity contribution made by wind power plants. It is critical to accurately characterize the capacity value of these wind power plants and the variability of the capacity value over the long term. This is important in order to avoid the cost of keeping extra power plants operational while still being able to cover the demand for power reliably. This capacity value calculation is …

Improving Sea-Surface Remote Sensing Of Ocean Wind Vectors By Scatterometers, Joseph W. Sapp

Doctoral Dissertations

Though scatterometers have been used to sense global ocean surface wind vectors for over 40 years, there remain some significant shortcomings. The largest problems appear in retrieving the wind vector when the ocean is being driven by high wind speeds or when rain is present in the beam-illuminated volume. Geophysical model functions (GMFs) developed using data from high-wind events can improve retrievals at high wind speeds, but only if sufficient ground truth measurements exist in the scatterometer swath. Airborne scatterometers, such as the Imaging Wind and Rain Airborne Profiler (IWRAP) developed by the Microwave Remote Sensing Laboratory (MIRSL) at the …

On Applications Of Relational Data, Samamon Khemmarat

Doctoral Dissertations

With the advances of technology and the popularity of the Internet, a large amount of data is being generated and collected. Much of these data is relational data, which describe how people and things, or entities, are related to one another. For example, data from sale transactions on e-commerce websites tell us which customers buy or view which products. Analyzing the known relationships from relational data can help us to discover knowledge that can benefit businesses, organizations, and our lives. For instance, learning the products that are commonly bought together allows businesses to recommend products to customers and increase their …

Physically Equivalent Intelligent Systems For Reasoning Under Uncertainty At Nanoscale, Santosh Khasanvis

Doctoral Dissertations

Machines today lack the inherent ability to reason and make decisions, or operate in the presence of uncertainty. Machine-learning methods such as Bayesian Networks (BNs) are widely acknowledged for their ability to uncover relationships and generate causal models for complex interactions. However, their massive computational requirement, when implemented on conventional computers, hinders their usefulness in many critical problem areas e.g., genetic basis of diseases, macro finance, text classification, environment monitoring, etc. We propose a new non-von Neumann technology framework purposefully architected across all layers for solving these problems efficiently through physical equivalence, enabled by emerging nanotechnology. The architecture builds …

Morphology Evolution Mechanisms Of Low Band Gap Polymer-Based Photovoltaics, Sunzida Ferdous

Doctoral Dissertations

An optimal nanoscale phase separation between the donor (generally, a conjugated polymer) and the acceptor (generally, a fullerene derivative) materials is one of the major requirements for obtaining high efficiency organic photovoltaic (OPV) device. Recent methods of controlling such nanostructure morphology in a bulkheterojunction (BHJ) OPV device involve addition of a small amount of solvent additive to the donor and acceptor solutions. The idea is to retain the acceptor materials into the solution for a longer period of time during the film solidification process, thus allowing the donor material to crystallize earlier. The ultimate morphology resulting from the solvent casting …

Effect Of Processing History And Material Properties On The Growth Of Wrinkle Amplitude, Yu-Cheng Chen

Doctoral Dissertations

Wrinkling has been employed by many organisms to form unique topography, such as fingerprints, gut villi, and surface of flower petal cells. The wavy wrinkle structure provides friction enhancement, surface area increase, optical, and wetting properties improvement. Inspired by Nature, scientists have created wrinkles synthetically and proposed numerous uses for them. However, wrinkling surfaces encounters limitations on achieving massive area and high amplitude-to-wavelength ratio (aspect ratio). The three phase contact line wrinkling technique creates well-defined wrinkles in a continuous fashion, and has great potential to scale-up for massive production. In addition to the velocity dependent adhesion force, we find the …

Process-Structure-Property Relationship In Ultra High Molecular Weight Polytetrafluoroethylene And Double Network Epoxies, Ranadip Ganguly

Doctoral Dissertations

The focus of this dissertation is to develop a fundamental understanding of process-structure-property relationship in two different classes of polymers: semi-crystalline Ultra High Molecular Weight Polytetrafluoroethylene (UHMWPTFE) and amorphous glassy double network (DN) epoxies. Conventional melt processing techniques such as extrusion and injection molding cannot be applied to UHMWPTFE due to its very high melt viscosity (10¹⁰-10¹¹ poise). Therefore, UHMWPTFE is industrially processed by a modified metallurgy technology-sintering. However, the fundamental mechanism for UHMWPTFE sintering is unknown. Further, this process is highly time consuming, cost inefficient and hinders the recyclability of the material. The first part of …