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Full-Text Articles in Engineering

Design For Auditory Displays: Identifying Temporal And Spatial Information Conveyance Principles, Ali Ahmad Jan 2007

Design For Auditory Displays: Identifying Temporal And Spatial Information Conveyance Principles, Ali Ahmad

Electronic Theses and Dissertations

Designing auditory interfaces is a challenge for current human-systems developers. This is largely due to a lack of theoretical guidance for directing how best to use sounds in today's visually-rich graphical user interfaces. This dissertation provided a framework for guiding the design of audio interfaces to enhance human-systems performance. This doctoral research involved reviewing the literature on conveying temporal and spatial information using audio, using this knowledge to build three theoretical models to aid the design of auditory interfaces, and empirically validating select components of the models. The three models included an audio integration model that outlines an end-to-end process …

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Knowledge Based Measurement Of Enhancing Brain Tissue In Anisotropic Mr Imagery, Eric Leach Jan 2007

Knowledge Based Measurement Of Enhancing Brain Tissue In Anisotropic Mr Imagery, Eric Leach

Electronic Theses and Dissertations

Medical Image Analysis has emerged as an important field in the computer vision community. In this thesis, two important issues in medical imaging are addressed and a solution for each is derived and synergistically combined as one coherent system. Firstly, a novel approach is proposed for High Resolution Volume (HRV) construction by combining different frequency components at multiple levels, which are separated by using a multi-resolution pyramid structure. Current clinical imaging protocols make use of multiple orthogonal low resolution scans to measure the size of the tumor. The highly anisotropic data result in difficulty and even errors in tumor assessment. …

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Anchoring Energy And Pretilt Angle Effects On Liquid Crystal Response Time, Xiangyi Nie Jan 2007

Anchoring Energy And Pretilt Angle Effects On Liquid Crystal Response Time, Xiangyi Nie

Electronic Theses and Dissertations

This dissertation covers some important topics on the liquid crystal-substrate surface effects, including theoretical derivations and confirming experimental results. The research work is expected to make important impacts on liquid crystal device designs and to open new doors for further research along these topics. In this dissertation, a novel high-electric-field technique is developed to characterize the anchoring energy of vertically-aligned liquid crystal cells. Both theoretical analyses and confirming experimental results are presented. Vertically-aligned liquid crystal cells with buffed polyimide alignment layers are used to validate the measurement techniques. Based on the voltage-dependent transmittance of the liquid crystal cells, a linear …

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A Study Of Equatorial Ionopsheric Variability Using Signal Processing Techniques, Xiaoni Wang Jan 2007

A Study Of Equatorial Ionopsheric Variability Using Signal Processing Techniques, Xiaoni Wang

Electronic Theses and Dissertations

The dependence of equatorial ionosphere on solar irradiances and geomagnetic activity are studied in this dissertation using signal processing techniques. The statistical time series, digital signal processing and wavelet methods are applied to study the ionospheric variations. The ionospheric data used are the Total Electron Content (TEC) and the critical frequency of the F2 layer (foF2). Solar irradiance data are from recent satellites, the Student Nitric Oxide Explorer (SNOE) satellite and the Thermosphere Ionosphere Mesosphere Energetics Dynamics (TIMED) satellite. The Disturbance Storm-Time (Dst) index is used as a proxy of geomagnetic activity in the equatorial region. The results are summarized …

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Modeling And Analysis Of The Eds Maglev System With The Halbach Magnet Array, Wonsuk Ko Jan 2007

Modeling And Analysis Of The Eds Maglev System With The Halbach Magnet Array, Wonsuk Ko

Electronic Theses and Dissertations

The magnetic field analysis based on the wavelet transform is performed. The Halbach array magnetic field analysis has been studied using many methods such as magnetic scalar potential, magnetic vector potential, Fourier analysis and Finite Element Methods. But these analyses cannot identify a transient oscillation at the beginning stage of levitation. The wavelet transform is used for analyzing the transient oscillatory response of an EDS Maglev system. The proposed scheme explains the under-damped dynamics that results from the cradle's dynamic response to the irregular distribution of the magnetic field. It suggests this EDS Maglev system that responds to a vertical …

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Towards A Self-Calibrating Video Camera Network For Content Analysis And Forensics, Imran Junejo Jan 2007

Towards A Self-Calibrating Video Camera Network For Content Analysis And Forensics, Imran Junejo

Electronic Theses and Dissertations

Due to growing security concerns, video surveillance and monitoring has received an immense attention from both federal agencies and private firms. The main concern is that a single camera, even if allowed to rotate or translate, is not sufficient to cover a large area for video surveillance. A more general solution with wide range of applications is to allow the deployed cameras to have a non-overlapping field of view (FoV) and to, if possible, allow these cameras to move freely in 3D space. This thesis addresses the issue of how cameras in such a network can be calibrated and how …

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Shock-Tube Investigation Of Ignition Delay Times Of Blends Of Methane And Ethane With Oxygen, Brian Christopher Walker Jan 2007

Shock-Tube Investigation Of Ignition Delay Times Of Blends Of Methane And Ethane With Oxygen, Brian Christopher Walker

Electronic Theses and Dissertations

The combustion behavior of methane and ethane is important to the study of natural gas and other alternative fuels that are comprised primarily of these two basic hydrocarbons. Understanding the transition from methane-dominated ignition kinetics to ethane-dominated kinetics for increasing levels of ethane is also of fundamental interest toward the understanding of hydrocarbon chemical kinetics. Much research has been conducted on the two fuels individually, but experimental data of the combustion of blends of methane and ethane is limited to ratios that recreate typical natural gas compositions (up to ~20% ethane molar concentration). The goal of this study was to …

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Optimization Of Zonal Wavefront Estimation And Curvature Measurements, Weiyao Zou Jan 2007

Optimization Of Zonal Wavefront Estimation And Curvature Measurements, Weiyao Zou

Electronic Theses and Dissertations

Optical testing in adverse environments, ophthalmology and applications where characterization by curvature is leveraged all have a common goal: accurately estimate wavefront shape. This dissertation investigates wavefront sensing techniques as applied to optical testing based on gradient and curvature measurements. Wavefront sensing involves the ability to accurately estimate shape over any aperture geometry, which requires establishing a sampling grid and estimation scheme, quantifying estimation errors caused by measurement noise propagation, and designing an instrument with sufficient accuracy and sensitivity for the application. Starting with gradient-based wavefront sensing, a zonal least-squares wavefront estimation algorithm for any irregular pupil shape and size …

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Design, Modeling, And Control Of Three-Port Converters For Solar Power Applications, Justin M. Reese Jan 2007

Design, Modeling, And Control Of Three-Port Converters For Solar Power Applications, Justin M. Reese

Electronic Theses and Dissertations

This paper describes the results of research into multi-port converter design and control, specifically a pair of three-port topologies based on the half-bridge and full-bridge topologies. These converters are capable of simultaneous and independent regulation of two out of their three ports, while the third port provides the power balance in the system. A dynamic model was developed for each topology to aid in testing and for designing the control loops. The models were then used to design the control structures, and the results were tested in Simulink. In addition, a basic outline of a system level architecture to control …

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Effects Of Position, Orientation, And Infiltrating Material On Three Dimensional Printing Models, Joseph William Frascati Jan 2007

Effects Of Position, Orientation, And Infiltrating Material On Three Dimensional Printing Models, Joseph William Frascati

Electronic Theses and Dissertations

This research defined and evaluated mechanical properties of prototypes created using a plaster based three-dimensional printing (3DP) system commercialized by Z Corporation. 3DP is one of the fastest growing forms of rapid prototyping. Till date, there is little or no information available on material properties of infiltrants used in 3DP. This research work evaluated and documented some of the useful information for 3DP users by determining the effect of build position, build orientation and infiltration materials on the strength of prototypes. The study was performed in three different phases to limit the processing variables and to arrive at definite conclusions …

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Verification Of Pilot-Scale Iron Release Models, Stephen Glatthorn Jan 2007

Verification Of Pilot-Scale Iron Release Models, Stephen Glatthorn

Electronic Theses and Dissertations

A model for the prediction of color release from a pilot distribution system was created in 2003 by Imran. This model allows prediction of the release of color from aged cast iron and galvanized steel pipes as a function of water quality and hydraulic residence time. Color was used as a surrogate measurement for iron, which exhibited a strong linear correlation. An anomaly of this model was an absence of a term to account for pH, due to the influent water being well stabilized. A new study was completed to evaluate the effectiveness of corrosion inhibitors against traditional adjustment. Two …

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Thermodynamic Studies On The Synthesis Of Nitrides And Epitaxial Growth Of Ingan, Zinki Monga Jan 2007

Thermodynamic Studies On The Synthesis Of Nitrides And Epitaxial Growth Of Ingan, Zinki Monga

Electronic Theses and Dissertations

Nitride semiconductor materials have been used in a variety of applications, such as LEDs, lasers, photovoltaic cells and medical applications. If incandescent bulbs could be replaced by white GaN LEDs, they would not only provide compactness and longer lifetime, but this would also result in huge energy savings. A renewed interest in InGaN emerged recently after it was discovered that the band gap for InN is 0.7eV, instead of the previously published value of 1.9eV. Thus InGaN solid solutions cover almost the whole visible spectrum, from a band gap of 3.34eV for GaN and 0.7eV for InN. Hence, InGaN can …

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Quantification Of Emissions From Lawn And Garden Equipment In Central Florida, Megan Leigh Crum Jan 2007

Quantification Of Emissions From Lawn And Garden Equipment In Central Florida, Megan Leigh Crum

Electronic Theses and Dissertations

The objective of this study was to evaluate the practical limits of EPA's NONROAD 2005 to accurately simulate Central Florida conditions, especially with regard to lawn and garden equipment. In particular we investigated a NONROAD emission inventory using default inputs and then created a locally specific emission inventory. These emission inventories were prepared for Orange, Osceola, and Seminole county and focused only on the VOC and NOx emissions caused by lawn and garden equipment. The model was manipulated to assess its ability to represent this specific category of nonroad equipment for a given airshed first by running a base case …

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Advanced Coding And Modulation For Ultra-Wideband And Impulsive Noises, Libo Yang Jan 2007

Advanced Coding And Modulation For Ultra-Wideband And Impulsive Noises, Libo Yang

Electronic Theses and Dissertations

The ever-growing demand for higher quality and faster multimedia content delivery over short distances in home environments drives the quest for higher data rates in wireless personal area networks (WPANs). One of the candidate IEEE 802.15.3a WPAN proposals support data rates up to 480 Mbps by using punctured convolutional codes with quadrature phase shift keying (QPSK) modulation for a multi-band orthogonal frequency-division multiplexing (MB-OFDM) system over ultra wideband (UWB) channels. In the first part of this dissertation, we combine more powerful near-Shannon-limit turbo codes with bandwidth efficient trellis coded modulation, i.e., turbo trellis coded modulation (TTCM), to further improve the …

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Identification And Suitability Of A Non-Anthropomorphic Meta-Language Framework In Military Applications, Gilbert Cardona Jan 2007

Identification And Suitability Of A Non-Anthropomorphic Meta-Language Framework In Military Applications, Gilbert Cardona

Electronic Theses and Dissertations

Humans carry mental models concerning the behaviors, looks, and operation of products, tools, and items used in their daily lives. When these items do not fit a user's conceptual model confusion and inefficiency occur. There are four basic types of mental models based on interactive activities: 1) instructing, 2) conversing, 3) manipulating and navigating, and 4) exploring and browsing. This thesis will focus on the conversing conceptual model and its application to communications between human-agent teams to best fit a user's mental model for that communication. A non-anthropomorphic framework does not exist for use in military applications such as; target …

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Learning, Detection, Representation, Indexing And Retrieval Of Multi-Agent Events In Videos, Asaad Hakeem Jan 2007

Learning, Detection, Representation, Indexing And Retrieval Of Multi-Agent Events In Videos, Asaad Hakeem

Electronic Theses and Dissertations

The world that we live in is a complex network of agents and their interactions which are termed as events. An instance of an event is composed of directly measurable low-level actions (which I term sub-events) having a temporal order. Also, the agents can act independently (e.g. voting) as well as collectively (e.g. scoring a touch-down in a football game) to perform an event. With the dawn of the new millennium, the low-level vision tasks such as segmentation, object classification, and tracking have become fairly robust. But a representational gap still exists between low-level measurements and high-level understanding of video …

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Two-Dimensional Guided Mode Resonant Structures For Spectral Filtering Applications, Sakoolkan Boonruang Jan 2007

Two-Dimensional Guided Mode Resonant Structures For Spectral Filtering Applications, Sakoolkan Boonruang

Electronic Theses and Dissertations

Guided mode resonant (GMR) structures are optical devices that consist of a planar waveguide with a periodic structure either imbedded in or on the surface of the structure. The resonance anomaly in GMR structures has many applications as dielectric mirrors, tunable devices, sensors,and narrow spectral band reflection filters. A desirable response from a resonant grating filter normally includes a nearly 100% narrowband resonant spectral reflection (transmission), and a broad angular acceptance at either normal incidence or an oblique angle of incidence. This dissertation is a detailed study of the unique nature of the resonance anomaly in GMR structures with two-dimensional …

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High Birefringence Liquid Crystals For Optical Communications, Amanda Jane Parish Jan 2007

High Birefringence Liquid Crystals For Optical Communications, Amanda Jane Parish

Electronic Theses and Dissertations

High birefringence (Δn > 0.4) nematic liquid crystals are particularly attractive for infrared applications because they enable a thinner cell gap to be used for achieving fast response time and improved diffraction efficiency. In this thesis, the mesomorphic and electro‐optic properties of several new fluorinated isothiocyanate (NCS) terphenyl and phenyl tolane single compounds and mixtures are reported. The single compounds demonstrated Δn~0.35‐0.52 in the visible spectral region at room temperature and exhibit relatively low viscosity. It was found that lateral fluorine substitutions and short alkyl chains eliminate smectic phase and lower the melting temperature of the single compounds. However, the consequence …

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Discrete Surface Solitons, Sergiy Suntsov Jan 2007

Discrete Surface Solitons, Sergiy Suntsov

Electronic Theses and Dissertations

Surface waves exist along the interfaces between two different media and are known to display properties that have no analogue in continuous systems. In years past, they have been the subject of many studies in a diverse collection of scientific disciplines. In optics, one of the mechanisms through which optical surface waves can exist is material nonlinearity. Until recently, most of the activity in this area was focused on interfaces between continuous media but no successful experiments have been reported. However, the growing interest that nonlinear discrete optics has attracted in the last two decades has raised the question of …

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Design And Demonstration Of Meanderline Retarders At Infrared Frequencies, Jeffrey Scott Tharp Jan 2007

Design And Demonstration Of Meanderline Retarders At Infrared Frequencies, Jeffrey Scott Tharp

Electronic Theses and Dissertations

Meanderline structures are widely used as engineered birefringent materials for waveplates and retarders at radiofrequencies, and have been previously demonstrated at frequencies up to 90 GHz in the millimeter-wave band. In this dissertation, we present results related to the modeling, fabrication, and experimental characterization of meanderlines across the range from 30 to 100 THz, in the long-wave and mid-wave infrared bands. Specific issues addressed in these new designs include spectral dispersion and angular dependence of the retardance, as well as axial ratio and throughput. The impact resulting from the infrared properties of the metals and dielectrics is explicitly included throughout. …

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Functional Disaster Resistant Buildings, Florida Solar Energy Center, William Young Dec 2006

Functional Disaster Resistant Buildings, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Natural disasters, such as hurricanes, floods, tornados, tsunami and earthquakes, are becoming a greater problem as they destroy lives, 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. One proactive strategy to minimize this type of destruction and disruption to lives is the implementation of disaster-resistant buildings that are energy efficient, fortified to the latest codes, and incorporate renewable energy systems. This approach uses the best energy-efficient buildings, fortified to the latest …

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Problems And Solutions: Training Disaster Organizations On The Use Of Pv, Florida Solar Energy Center, William Young Dec 2006

Problems And Solutions: Training Disaster Organizations On The Use Of Pv, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

In 1992, the Florida Solar Energy Center (FSEC) and Sandia National Laboratories (SNL) assisted the University of Miami Field Epidemiology Survey Team (FEST) with photovoltaic systems to power temporary medical clinics after Hurricane Andrew struck south Dade County. At that time, it became apparent that there were no educational materials prepared for disaster relief or emergency management personnel on the use of photovoltaic (PV) to supply electrical power in response to a disaster. This need prompted FSEC to create an education program to develop awareness and train organizations on the proper use of PV in disasters. Since then, FSEC has …

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Grid-Connected Photovoltaic System Design Review And Approval, Florida Solar Energy Center, James Dunlop Dec 2006

Grid-Connected Photovoltaic System Design Review And Approval, Florida Solar Energy Center, James Dunlop

FSEC Energy Research Center®

This document provides details of operations and procedures for the approval of grid-connected photovoltaic (PV) system designs and documentation conducted by the Florida Solar Energy Center. The principal goal of this process is to help ensure the safety and quality of installed PV systems, and provides an assurance to installers, consumers and financiers that approved designs meet accepted codes and industry practices, and are accompanied by a complete System Manual that meets the minimum requirements outlined in this document.

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Test Method For Photovoltaic Module Ratings, Florida Solar Energy Center, Kevin Lynn Dec 2006

Test Method For Photovoltaic Module Ratings, Florida Solar Energy Center, Kevin Lynn

FSEC Energy Research Center®

This document describes the testing and reporting requirements for certification and labeling of photovoltaic modules (PV) for their power ratings. The test methods and procedures chosen for this purpose are based on consensus standards of relevant committees of the Institute of Electrical and Electronic Engineers (IEEE), the American Society for Testing and Materials (ASTM), or the International Electrotechnical Commission (IEC).

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Executive Summary: Evaluation Of The Impact Of Vacant Home Space Conditioning Strategies On Summer Relative Humidity, Energy, And Peak Load; Phase Ii, Florida Solar Energy Center, James Cummings Dec 2006

Executive Summary: Evaluation Of The Impact Of Vacant Home Space Conditioning Strategies On Summer Relative Humidity, Energy, And Peak Load; Phase Ii, Florida Solar Energy Center, James Cummings

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 …

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Solar Dhw Storage Tanks And Systems, Florida Solar Energy Center Dec 2006

Solar Dhw Storage Tanks And Systems, Florida Solar Energy Center

FSEC Energy Research Center®

Water is by far the most common storage medium in solar domestic hot water systems. Rock storage is another method of sensible heat storage, but is not generally used in systems that are exclusively DHW. Storage of heat in solutions of phase-changing salts is extremely rare in DHW systems and therefore is not discussed.

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Field Monitoring And Computer Modeling To Determine Energy And Demand Savingsfrom The Melink Intellihood Exhaust And Make-Up Air Control System At Two Supermarkets, One Restaurant, And One Fast Food Restaurant, Florida Solar Energy Center, James Cummings Nov 2006

Field Monitoring And Computer Modeling To Determine Energy And Demand Savingsfrom The Melink Intellihood Exhaust And Make-Up Air Control System At Two Supermarkets, One Restaurant, And One Fast Food Restaurant, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

Note: Only the Executive Summary of this proprietary report is available for public download.

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Balanced Return Air, Duct Airtightness, And Combustion/Dilution Air Code Compliance In 40 Central Florida Homes, Florida Solar Energy Center, James Cummings Nov 2006

Balanced Return Air, Duct Airtightness, And Combustion/Dilution Air Code Compliance In 40 Central Florida Homes, Florida Solar Energy Center, James Cummings

FSEC Energy Research Center®

This report has been extracted from a larger report titled "Florida Building Code - Enhance Florida's Building to Next-Generation Energy & Mechanical Codes and Enrich Compliance", FSEC-CR-1678-06, November 29, 2006, which can be found at http://www.fsec.ucf.edu/en/publications/pdf/FSEC-CR-1678-06.pdf

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Florida Building Code - Enhance Florida's Building To Next-Generation Energy & Mechanical Codes And Enrich Compliance, Florida Solar Energy Center, Muthusamy V. Swami Nov 2006

Florida Building Code - Enhance Florida's Building To Next-Generation Energy & Mechanical Codes And Enrich Compliance, Florida Solar Energy Center, Muthusamy V. Swami

FSEC Energy Research Center®

The project implemented ASHRAE 90.1 2004 into Florida's compliance tool, EnergyGauge, to allow inclusion of the methodologies and rule sets of ASHRAE 90.1-2004. The project also implemented IECC 2003 into Florida's compliance tool to allow inclusion of the methodologies of Chapters 4, 5, and 6 of the International Energy Conservation Code 2003 (IECC 2003). Field testing was completed in 40 central Florida homes (built after March 1, 2002) to examine compliance with the balanced return air, duct leakage, and combustion/dilution air requirements of the Florida Mechanical Code. A course titled Complying with Duct System Requirements of the Florida Energy Code …

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Comparison Of Solar Hot Water Systems Simulated In Energygauge Usa And Trnsys 15, Florida Solar Energy Center, Michael Anello Nov 2006

Comparison Of Solar Hot Water Systems Simulated In Energygauge Usa And Trnsys 15, Florida Solar Energy Center, Michael Anello

FSEC Energy Research Center®

This document is meant to serve as a detailed summary of the comparison between the simulation methods of EnergyGauge USA and TRNSYS (version 15) relating to solar hot water systems. The initial motivation behind this comparison was to verify that the f-chart model created for EnergyGauge's solar hot water calculations was reporting the correct results. To this end, models of three systems were created in TRNSYS in order to serve as a baseline for the EnergyGauge results. The three systems modeled were: Liquid-active closed loop (LACL), Liquid-active open loop (LAOL), Integrated collector storage (ICS). This document will detail each of …

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