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Full-Text Articles in Engineering

Microbial Source Tracking: Tools For Refining Total Maximum Daily Load Assessments (2005), Stormwater Academy Nov 2005

Microbial Source Tracking: Tools For Refining Total Maximum Daily Load Assessments (2005), Stormwater Academy

BMP Trains Research and Publications

For over 100 years, indicator bacteria of fecal origin have been used to assess water quality and alert managers to increased risk of the presence of human pathogens. While these indicator organisms, including total coliforms and fecal coliforms, have helped protect public health for decades, they are now being utilized as surrogates for pathogens in total maximum daily load (TMDL) programs that are mandated by the US Environmental Protection Agency. The goal of TMDL assessment, which is carried out by the Florida Department of Environmental Protection in Florida, is ultimately to identify the sources of contaminant loading to Florida waters …


Energy Efficient Transportation For Florida, Florida Solar Energy Center, Danny Parker Nov 2005

Energy Efficient Transportation For Florida, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

Nearly 30% of energy used in Florida is consumed by our 13 million personal automobiles. Annual gasoline consumption in Florida is about 7.5 billion gallons. Florida also has more registered cars per capita than any other state in the U.S. - nearly one car for each person. The average Florida automobile is driven over 10,000 miles a year burning about 550 gallons of gasoline and costing its owner about $1,500 in fuel costs alone (not to mention payments, insurance, service, repairs, tires, tags, license etc.). Based on a comprehensive analysis, total automobile operating costs average over $850 per month.


Quantifying The Effect Of A Vegetated Littoral Zone On Wet Detention Pond Pollutant Load Reduction (2005), Stormwater Academy Sep 2005

Quantifying The Effect Of A Vegetated Littoral Zone On Wet Detention Pond Pollutant Load Reduction (2005), Stormwater Academy

BMP Trains Research and Publications

This report describes an investigation sponsored by the Florida Department of Environmental Protection (FDEP), in which DB Environmental, Inc., with assistance from Community Watershed Fund, evaluated the potential of littoral zone vegetation to enhance contaminant removal performance of a wet detention pond.

For this effort, we constructed an experimental facility at a 1 hectare wet detention pond in Brevard Co, Florida that contained pre-existing littoral vegetation (distinct stands of cattail (Typha sp.) and pickerelweed (Pontederia cordata)) in addition to an unvegetated shoreline. Ten compartments, 3.7 m by 9.0 m, were deployed within the facility, effectively isolating sections of the pond. …


Technical Support For Development Of An Attic Simulation Model For The California Energy Commission, Florida Solar Energy Center, Danny Parker Sep 2005

Technical Support For Development Of An Attic Simulation Model For The California Energy Commission, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The California Energy Commission (CEC) is developing a new attic simulation model for assessing residential energy performance within its Title 24 residential compliance methodology. Within this project, we are providing technical support to assist Bruce Wilcox and CEC in development of the model based on Florida Solar Energy Center (FSEC) experience with similar models. We assisted the effort by using data from FSEC instrumented facilities to help verify the eventual simulation. We also outlined critical issues for modeling with the development of the simulation. Given the importance of attic ventilation, we are also conducting new studies of varied ventilation rates …


Stormwater Intelligent Control System (2005), Martin Wanielista Aug 2005

Stormwater Intelligent Control System (2005), Martin Wanielista

BMP Trains Research and Publications

Water restrictions, pollution control, volume balances, and the emergence of stormwater utilities have lead to the development of an automated intelligent system (“I-Water”) for water use and control. With the use of this system, water stored in stormwater ponds or in the surficial aquifer is not discharged to surface waters because it is used to meet water demands, such as, lawn irrigation, environmental protection, agriculture, drinking and industrial uses.

The drop in groundwater levels and the increasing use of reclaimed water illustrates a need for alternative water supplies. Ground water depletion is occurring which is adding to the destruction of …


Showering In The Sun, Florida Solar Energy Center, James Haggard Aug 2005

Showering In The Sun, Florida Solar Energy Center, James Haggard

FSEC Energy Research Center®

For thousands of years, man has used energy from the sun to heat water. Today, the typical way of obtaining hot water for a shower is through a residential or commercial thermal system installed on a building. This type of shower is too big and heavy to use outdoors, although camping facilities and parks may have such systems for their patrons. Original outdoor showers that were developed for use in remote locations were bulky and not particularly portable. Today's solar shower is designed to be practical for camping, recreational and marine use. New products are made of plastic for lighter …


Disasters: Photovoltaics For Special Needs, Florida Solar Energy Center, William Young Aug 2005

Disasters: Photovoltaics For Special Needs, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

The National Hurricane Center tracks the path of a hurricane to determine where it will make landfall. People in harm's way are informed of its approach and the need to evaluate options to prevent injury and protect lives. One of the many groups of people at high risk is those with special needs. They have health conditions that require special care. Before a disaster, these individuals live in hospitals, care facilities and homes. During and following a disaster, many would be moved, along with their supplies, equipment and a caretaker, to a special needs shelter. Others would stay with relatives …


Renewable Energy And Disaster-Resistant Buildings, Florida Solar Energy Center, William Young Aug 2005

Renewable Energy And Disaster-Resistant Buildings, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Hurricanes, floods, tornados and earthquakes create natural disasters that can destroy homes, businesses and the natural environment. Such disasters can happen with little or no warning, leaving hundreds or even thousands of people without medical services, potable water, sanitation, communications and electrical services for up to several weeks. The 2004 hurricane season ravaged the State of Florida, U.S.A., with four major hurricanes within a 6-week timeframe. Over nine million people evacuated their homes and damage to property was extensive.

One proactive strategy to minimize this type of destruction and disruption to lives is the implementation of disaster-resistant buildings that are …


Flexible Roofing Facility: 2004 Summer Test Results, Florida Solar Energy Center, Danny Parker Jul 2005

Flexible Roofing Facility: 2004 Summer Test Results, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Flexible Roof Facility (FRF) is a test facility in Cocoa, Florida designed to evaluate five roofing systems at a time against a control roof with black shingles and vented attic (Figure E-1). Since 1989 the testing has evaluated how roofing systems impact summer residential cooling energy use and peak demand. In the summer of 2004, the following roofing systems were tested. Materials tested were: Galvalume® unfinished (unpainted) 5-vee metal with vented attic (3rd year of exposure), galvanized unfinished 5-vee metal with vented attic (3rd year of exposure, black shingles with standard attic ventilation (Control Test Cell), white standing seam …


Development Of High Efficiency Air Conditioner Condenser Fans, Florida Solar Energy Center, Danny Parker Jun 2005

Development Of High Efficiency Air Conditioner Condenser Fans, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

With sponsorship from the U.S. Department of Energy, a research project has designed, fabricated and tested improvements to an air conditioner outdoor unit fan system. The primary objective was to improve condenser fan performance while reducing motor power. We also examined potential changes to the condenser exhaust configuration to enhance air moving efficiency performance. A secondary objective was to provide sound reductions as lower noise AC equipment is important to consumers.

Within conducted tests, an improved high efficiency fan design and advanced exhaust diffuser section reduced fan motor power requirements by approximately 49 W (26%) while providing superior air flow. …


Literature Review Of The Impact And Need For Attic Ventilation In Florida Homes, Florida Solar Energy Center, Danny Parker May 2005

Literature Review Of The Impact And Need For Attic Ventilation In Florida Homes, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

The Florida Department of Community Affairs (DCA) is seeking to examine the impact and necessity of residential attic ventilation in Florida homes. Here, we provide technical support by examining existing data sources on the impacts of attic ventilation both on cooling and heating energy use as well as to attic and home moisture levels. In particular we evaluate the issues with sealed attic construction where the attic is unvented and expanded foam insulation is applied directly to the underside of the roof decking.

We also report the data from Florida Solar Energy Center (FSEC) instrumented facilities to add unique information …


Theoretical Evaluation Of The Nightcool Nocturnal Radiation Cooling Concept, Florida Solar Energy Center, Danny Parker Apr 2005

Theoretical Evaluation Of The Nightcool Nocturnal Radiation Cooling Concept, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

An evaluation has been conducted of the potential of a night sky cooling system to substantially reduce space cooling needs in homes in North American climates. The report describes the innovative residential cooling system which uses nocturnal night sky radiation from a roof integrated radiator. The system uses a sealed attic covered by a highly conductive metal roof which is selectively linked by air flow to the main zone with the attic zone to provide cooling- largely during nighttime hours. Available house mass is used to store sensible cooling. Additional dehumidification is done during the evening hours as warranted by …


Executive Summary: Evaluation Of The Impact Of Vacant Home Space Conditioning Strategies On Summer Relative Humidity, Energy, And Peak Load, Florida Solar Energy Center, Charles Withers, Jr. Jan 2005

Executive Summary: Evaluation Of The Impact Of Vacant Home Space Conditioning Strategies On Summer Relative Humidity, Energy, And Peak Load, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

The Vacant Home Space Conditioning Study was sponsored by Florida Power & Light (FPL) as part of its Conservation R&D Program and carried out by the Florida Solar Energy Center (FSEC). In the US, about one in four retiree "snowbirds" make Florida their destination to escape the northern cold. Snowbird residents number more than 900,000 in Florida during the winter. In some counties of FPL's territory these seasonal residents compose up to 15% of the population (Shih, 1981). This pattern of seasonal occupancy creates a need for space conditioning guidelines for vacant homes to avoid mold problems while minimizing both …


Arc-Discharge In Solution: A Novel Synthesis Method For Carbon Nanotubes And In Situ Decoration Of Carbon Nanotubes With Nanoparticles, Debasis Bera Jan 2005

Arc-Discharge In Solution: A Novel Synthesis Method For Carbon Nanotubes And In Situ Decoration Of Carbon Nanotubes With Nanoparticles, Debasis Bera

Electronic Theses and Dissertations

Nanotechnology has reached the status of the 21st century's leading science and technology based on fundamental and applied research during the last two decades. An important feature of nanotechnology is to bridge the crucial dimensional gap between the atomic and molecular fundamental sciences and microstructural scale of engineering. Accordingly, it is very important to have an in-depth understanding of the synthesis of nanomaterials for the use of state-of-the-art high technological devices with enhanced properties. Recently, the 'bottom-up' approach for the fabrication of nanomaterials has received a great deal of attention for its simplicity and cost effectiveness. Tailoring the various parameters …


Development Of A Motor Speed Control System Using Matlab And Simulink, Implemented With A Digital Signal Processor, Andrew Klee Jan 2005

Development Of A Motor Speed Control System Using Matlab And Simulink, Implemented With A Digital Signal Processor, Andrew Klee

Electronic Theses and Dissertations

This thesis describes an improved methodology for embedded software development. MATLAB and Simulink allow engineers to simplify algorithm development and avoid duplication of effort in deploying these algorithms to the end hardware. Special new hardware targeting capabilities of MATLAB and Simulink are described in detail. A motor control system design served to demonstrate the efficacy of this new method. Initial data was collected to help model the motor in Simulink. This allowed for the design of the open and closed loop control systems. The designed system was very effective, with good response and no steady state error. The entire design …


Effects Of Reduced Ras And Volume On Anaerobic Zone Performance For A Septic Wastewater Biological Phosphorous Removal System, Daniel Magro Jan 2005

Effects Of Reduced Ras And Volume On Anaerobic Zone Performance For A Septic Wastewater Biological Phosphorous Removal System, Daniel Magro

Electronic Theses and Dissertations

Enhanced Biological Phosphorous Removal (EBPR) performance was found to be adequate with reduced Return Activated Sludge (RAS) flows (50% of available RAS) to the anaerobic tank and smaller than typical anaerobic zone volume (1.08 hours hydraulic retention time or HRT). Three identical parallel biological nutrient removal (BNR) pilot plants were fed with strong, highly fermented (160 mg/L VFAs), domestic/industrial wastewater from a full scale wastewater treatment facility (WWTF). The pilot plants were operated at 100%, 50%, 40% and 25% RAS (percent of available RAS) flows to the anaerobic tank with the remaining RAS to the anoxic tank. In addition, varying …


Analysis And Simulation Tools For Solar Array Power Systems, Nattorn Pongratananukul Jan 2005

Analysis And Simulation Tools For Solar Array Power Systems, Nattorn Pongratananukul

Electronic Theses and Dissertations

This dissertation presents simulation tools developed specifically for the design of solar array power systems. Contributions are made in several aspects of the system design phases, including solar source modeling, system simulation, and controller verification. A tool to automate the study of solar array configurations using general purpose circuit simulators has been developed based on the modeling of individual solar cells. Hierarchical structure of solar cell elements, including semiconductor properties, allows simulation of electrical properties as well as the evaluation of the impact of environmental conditions. A second developed tool provides a co-simulation platform with the capability to verify the …


Enhancing Message Privacy In Wired Equivalent Privacy., Darshan Purandare Jan 2005

Enhancing Message Privacy In Wired Equivalent Privacy., Darshan Purandare

Electronic Theses and Dissertations

The 802.11 standard defines the Wired Equivalent Privacy (WEP) and encapsulation of data frames. It is intended to provide data privacy to the level of a wired network. WEP suffered threat of attacks from hackers owing to certain security shortcomings in the WEP protocol. Lately, many new protocols like WiFi Protected Access (WPA), WPA2, Robust Secure Network (RSN) and 802.11i have come into being, yet their implementation is fairly limited. Despite its shortcomings one cannot undermine the importance of WEP as it still remains the most widely used system and we chose to address certain security issues and propose some …


Famtile: An Algorithm For Learning High-Level Tactical Behavior From Observation, Brian Stensrud Jan 2005

Famtile: An Algorithm For Learning High-Level Tactical Behavior From Observation, Brian Stensrud

Electronic Theses and Dissertations

This research focuses on the learning of a class of behaviors defined as high-level behaviors. High-level behaviors are defined here as behaviors that can be executed using a sequence of identifiable behaviors. Represented by low-level contexts, these behaviors are known a priori to learning and can be modeled separately by a knowledge engineer. The learning task, which is achieved by observing an expert within simulation, then becomes the identification and representation of the low-level context sequence executed by the expert. To learn this sequence, this research proposes FAMTILE - the Fuzzy ARTMAP / Template-Based Interpretation Learning Engine. This algorithm attempts …


Solar-Based Single-Stage High-Efficiency Grid-Connected Inverter, Feng Tian Jan 2005

Solar-Based Single-Stage High-Efficiency Grid-Connected Inverter, Feng Tian

Electronic Theses and Dissertations

Renewable energy source plays an important role in the energy cogeneration and distribution. Traditional solar-based inverter system is two stages in cascaded, which has a simpler controller but low efficiency. A new solar-based single-stage grid-connected inverter system can achieve higher efficiency by reducing the power semiconductor switching loss and output stable and synchronized sinusoid current into the utility grid. Controlled by the digital signal processor, the inverter can also draw maximum power from the solar array, thereby maximizing the utilization of the solar array. In Chapter 1, a comparison between the traditional two-stage inverter and the single-stage inverter is made. …


Safety Issues Of Red-Light Running And Unprotected Left-Turn At Signalized Intersections, Xuedong Yan Jan 2005

Safety Issues Of Red-Light Running And Unprotected Left-Turn At Signalized Intersections, Xuedong Yan

Electronic Theses and Dissertations

Crashes categorized as running red light or left turning are most likely to occur at signalized intersections and resulted in substantial severe injuries and property damages. This dissertation mainly focused on these two types of vehicle crashes and the research methodology involved several perspectives. To examine the overall characteristics of red-light running and left-turning crashes, firstly, this study applied 1999-2001 Florida traffic crash data to investigate the accident propensity of three aspects of risk factors related to traffic environments, driver characteristics, and vehicle types. A quasi-induced exposure concept and statistical techniques including classification tree model and multiple logistic regression were …


Optimization Of An Unstructured Finite Element Mesh For Tide And Storm Surge Modeling Applications In The Western North Atlantic Ocean, Satoshi Kojima Jan 2005

Optimization Of An Unstructured Finite Element Mesh For Tide And Storm Surge Modeling Applications In The Western North Atlantic Ocean, Satoshi Kojima

Electronic Theses and Dissertations

Recently, a highly resolved, finite element mesh was developed for the purpose of performing hydrodynamic calculations in the Western North Atlantic Tidal (WNAT) model domain. The WNAT model domain consists of the Gulf of Mexico, the Caribbean Sea, and the entire portion of the North Atlantic Ocean found west of the 60° W meridian. This high resolution mesh (333K) employs 332,582 computational nodes and 647,018 triangular elements to provide approximately 1.0 to 25 km node spacing. In the previous work, the 333K mesh was applied in a Localized Truncation Error Analysis (LTEA) to produce nodal density requirements for the WNAT …


A Comparative Analysis Between Context-Based Reasoning (Cxbr) And Contextual Graphs (Cxgs)., Peterson Marthen Lorins Jan 2005

A Comparative Analysis Between Context-Based Reasoning (Cxbr) And Contextual Graphs (Cxgs)., Peterson Marthen Lorins

Electronic Theses and Dissertations

Context-based Reasoning (CxBR) and Contextual Graphs (CxGs) involve the modeling of human behavior in autonomous and decision-support situations in which optimal human decision-making is of utmost importance. Both formalisms use the notion of contexts to allow the implementation of intelligent agents equipped with a context sensitive knowledge base. However, CxBR uses a set of discrete contexts, implying that models created using CxBR operate within one context at a given time interval. CxGs use a continuous context-based representation for a given problem-solving scenario for decision-support processes. Both formalisms use contexts dynamically by continuously changing between necessary contexts as needed in appropriate …


Graph-Theoretic Approach To Modeling Propagation And Control Of Network Worms, Zoran Nikoloski Jan 2005

Graph-Theoretic Approach To Modeling Propagation And Control Of Network Worms, Zoran Nikoloski

Electronic Theses and Dissertations

In today's network-dependent society, cyber attacks with network worms have become the predominant threat to confidentiality, integrity, and availability of network computing resources. Despite ongoing research efforts, there is still no comprehensive network-security solution aimed at controling large-scale worm propagation. The aim of this work is fivefold: (1) Developing an accurate combinatorial model of worm propagation that can facilitate the analysis of worm control strategies, (2) Building an accurate epidemiological model for the propagation of a worm employing local strategies, (3) Devising distributed architecture and algorithms for detection of worm scanning activities, (4) Designing effective control strategies against the worm, …


Interdiffusion Analysis For Nicocraly And Nial Vs. Various Superalloys, Emmanuel Perez Jan 2005

Interdiffusion Analysis For Nicocraly And Nial Vs. Various Superalloys, Emmanuel Perez

Electronic Theses and Dissertations

Hot section components in gas turbines can be NiCoCrAlY-coated to provide the component with an Al reservoir that maintains a protective oxide layer on its surface. Over the service life of the component, the coatings degrade by composition and phase changes due to oxidation/hot-corrosion, and multicomponent interdiffusion from and into the superalloy substrate. In this study, the rate of Al interdiffusion into selected Ni-base superalloys using various diffusion couples of two-phase NiCoCrAlY (beta + gamma) and single beta-phase NiAl with the selected alloys is measured. The diffusion couples were examined with an emphasis on the composition-dependence of Al interdiffusion. Microstructural …


Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan Jan 2005

Instrumented Nanoindentation Studies Of Deformation In Shape Memory Alloys, Sudhir Rajagopalan

Electronic Theses and Dissertations

Near equi-atomic nickel titanium (NiTi) shape memory alloys (SMAs) are a class of materials characterized by their unique deformation behavior. In these alloys, deformation mechanisms such as mechanical twinning and stress induced phase transformation between a high symmetry phase (austenite) and a low symmetry phase (martensite) additionally occur and influence mechanical behavior and thus their functionality. Consequently, applications of SMAs usually call for precise phase transformation temperatures, which depend on the thermomechanical history and the composition of the alloy. Instrumented indentation, inherently a mechanical characterization technique for small sampling volumes, offers a cost effective means of empirically testing SMAs in …


Investigation Of High-K Gate Dielectrics And Metals For Mosfet Devices., Sriram Mannargudi Seshadri Jan 2005

Investigation Of High-K Gate Dielectrics And Metals For Mosfet Devices., Sriram Mannargudi Seshadri

Electronic Theses and Dissertations

Progress in advanced microlithography and deposition techniques have made feasible high- k dielectric materials for MOS transistors. The continued scaling of CMOS devices is pushing the Si-SiO2 to its limit to consider high-k gate dielectrics. The demand for faster, low power, smaller, less expensive devices with good functionality and higher performance increases the demand for high-k dielectric based MOS devices. This thesis gives an in-depth study of threshold voltages of PMOS and NMOS transistors using various high-k dielectric materials like Tantalum pent oxide (Ta2O5), Hafnium oxide (HfO2), Zirconium oxide (ZrO2) and Aluminum oxide (Al2O3) gate oxides. Higher dielectric constant may …


Solution Of Electromagnetic Scattering Parameters And Radiation Patterns Of Arbitrary Body Of Revolution Radiators, Wendell Brokaw Jan 2005

Solution Of Electromagnetic Scattering Parameters And Radiation Patterns Of Arbitrary Body Of Revolution Radiators, Wendell Brokaw

Electronic Theses and Dissertations

A novel full wave analysis method to determine the scattering parameters and the radiation field intensities of arbitrary Body of Revolution (BOR) radiators consisting of impenetrable media is explored through derived components of modal analysis and the method of moments (MoM). Modal excitation is utilized to excite the structural feed; allowing for a more accurate measure of the scattering parameters of the total structure as opposed to the use of external excitation sources. The derivation of the mode matching method introduces a novel approach to achieving a frequency independent coupling matrix that will reduce the computational requirements for iterations utilized …


Estimation Of Tangential Momentum Accommodation Coefficient Using Molecular Dynamics Simulation, George Finger Jan 2005

Estimation Of Tangential Momentum Accommodation Coefficient Using Molecular Dynamics Simulation, George Finger

Electronic Theses and Dissertations

The Tangential Momentum Accommodation Coefficient (TMAC) is used to improve the accuracy of fluid flow calculations in the slip flow regime. Under such conditions (indicated by Knudsen number greater than 0.001), the continuum assumption that a fluid velocity at a solid surface is equal to the surface velocity is inaccurate because relatively significant fluid "slip" occurs at the surface. Prior work has not led to a method to quickly estimate a value for TMAC - it is frequently assumed. In this work, Molecular Dynamics techniques are used to study the impacts of individual gas atoms upon solid surfaces to understand …


Solar Driven Photoelectrochemical Water Splitting For Hydrogen Generation Using Multiple Bandgap Tandem Of Cigs2 Pv Cells And Thin Film Photocatalyst, Anant Jahagirdar Jan 2005

Solar Driven Photoelectrochemical Water Splitting For Hydrogen Generation Using Multiple Bandgap Tandem Of Cigs2 Pv Cells And Thin Film Photocatalyst, Anant Jahagirdar

Electronic Theses and Dissertations

The main objective of this research was to develop efficient CuIn1-xGaxS2 (CIGS2)/CdS thin film solar cells for photoelectrochemical (PEC) water splitting to produce very pure hydrogen and oxygen. Efficiencies obtained using CIGS2 have been lower than those achieved using CuInSe2 and CuIn1-xGaxSe2. The basic limitation in the efficiencies is attributed to lower open circuit voltages with respect to the bandgap of the material. Presently, the main mechanism used to increase the open circuit voltage of these copper chalcopyrites (CuInSe2 and CuInS2) is the addition of gallium. However, addition of gallium has its own challenges. This research was intended to (i) …