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Full-Text Articles in Engineering

Pv Powering A Weather Station For Severe Weather, Florida Solar Energy Center, William Young Nov 1997

Pv Powering A Weather Station For Severe Weather, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

A natural disaster, such as Hurricane Andrew, destroys thousands of homes and businesses. The destruction from this storm left thousands of people without communications, potable water, and electric power. This prompted the Florida Solar Energy Center to study the application of solar electric power for use in disasters.

During this same period, volunteers at the Tropical Prediction Center at the National Hurricane Center (NHC) and the Miami Office of the National Weather Service (NWS) were working to increase the quantity and quality of observations received from home weather stations.

Many weather data collecting stations are at remote sites, which are …


Maine Guide To Energy Efficient Residential Construction : A Manual Of Accepted Practices, State Of Maine Energy Conservation Division Nov 1997

Maine Guide To Energy Efficient Residential Construction : A Manual Of Accepted Practices, State Of Maine Energy Conservation Division

Maine Collection

Maine Guide to Energy Efficient Residential Construction : A Manual of Accepted Practices

State of Maine Energy Conservation Division, Department of Economic and Community Development, 59 State House Station, Augusta, Maine 04333-0059

Second Edition - November, 1997

Contents: Dedication / Acknowledgements / Introduction / Part 1. Summary of Maine's Residential Energy Standards / Part 2. Siting and Initial Design Considerations / Part 3. Important Considerations for the Design Phase / Part 4. Recommended Construction Practices / Appendixes


Robotic Tcf And Rigid-Body Calibration Methods, Edward Red, Xuguang Wang Nov 1997

Robotic Tcf And Rigid-Body Calibration Methods, Edward Red, Xuguang Wang

Faculty Publications

For off-line programming to work, systematic methods must be developed to account for non-ideal performance of the parts and devices in the manufacturing cell. Although much of the literature focuses on robot inaccuracy, this paper considers practical methods for the tool control frame (TCF) calibration and rigid-body compensation required to close the inverse kinematics loop for target driven tasks.


Nonlinear Optimal Control Of A Hydraulically Actuated Positioning System, Timothy Mclain, Randal W. Beard Nov 1997

Nonlinear Optimal Control Of A Hydraulically Actuated Positioning System, Timothy Mclain, Randal W. Beard

Faculty Publications

In this paper, the nonlinear optimal control problem is formulated for the position control of an electrohydraulic servo system. The optimal control is given by the solution to the Hamilton-Jacobi-Bellman equation, which in this case cannot be solved explicitly. An alternative method, based upon successive Galerkin approximation, is used to obtain an approximate optimal solution. Preliminary simulation results, demonstrating the application of this approach to the position control of a hydraulically actuated device, are presented.


Extracting The Relative Grain Boundary Free Energy And Mobility Functions From The Geometry Of Microstructures, Brent L. Adams, D. Kinderlehrer, W. W. Mullins, Anthony D. Rollett, Shlomo Ta'asan Nov 1997

Extracting The Relative Grain Boundary Free Energy And Mobility Functions From The Geometry Of Microstructures, Brent L. Adams, D. Kinderlehrer, W. W. Mullins, Anthony D. Rollett, Shlomo Ta'asan

Faculty Publications

This work was supported primarily by the MRSEC Program of the National Science Foundation under Award Number DMR-9632556. This paper describes a method for extracting, from measurements of a polycrystal, the relative excess free energy and the relative mobility of the grain boundaries as functions of the crystallographic type (five degrees of freedom) and relevant thermodynamic variables. The method requires the simultaneous measurement of both the geometry and the crystallography of a large number of grain boundary intersections; the crystallographic information may be obtained from orientation imaging microscopy (OIM). For simplicity, the intersections will be assumed to be triple junctions …


Automobile Air Bag Inflation System Based On Fast Combustion Reaction, Yacoob Tabani Oct 1997

Automobile Air Bag Inflation System Based On Fast Combustion Reaction, Yacoob Tabani

Dissertations

Current automobile air bag inflator technology is complex, expensive and environmentally unsafe. A new and novel air bag inflator based on fast combustion reactions of methane-oxygen mixtures has been developed and studied. The thermodynamics and mass flow parameters of this new inflator have been modeled and found to be in agreement with experimental results.

The performance of the fast combustion inflator was evaluated in terms of pressure-time relationships inside the inflator and in a receiving tank simulating an air bag as well as the temperature-time relationship in the tank.

In order to develop this fast combustion inflator, several critical issues …


Electrocatalytic Control Of Exhaust Soot, Victor L. Callahan Oct 1997

Electrocatalytic Control Of Exhaust Soot, Victor L. Callahan

Dissertations

The feasibility of combining electrostatic precipitation and use of a catalytic wall in a straight tube reactor as a means of destroying soot particles was investigated. Enhanced particle diffusion to the wall by an applied electric field provided the means of particle capture for subsequent catalytic oxidation at the active surface in a small length tube.

Soot particles flowing in a gas stream are influenced by the following transport mechanisms: convective flux as a result of bulk flow, diffusion flux as a result of particle concentration or number density gradient, and an electrostatic flux from the coulombic attraction as charged …


Computational Determination Of Laminar Flow Loss Coefficients In 90° Channel Bend, Leonard Paul Parkin Oct 1997

Computational Determination Of Laminar Flow Loss Coefficients In 90° Channel Bend, Leonard Paul Parkin

Theses

Loss coefficients for laminar two dimensional incompressible channel (or duct) flow in a 90° bend are investigated using FEM software, FIDAP. This problem consists of a two dimensional duct with a 90° bend of constant radius flowing with water, at 70°F and atmositeno conditions. The bend radius to duct width ratios examined were 1.5 and 1.0. Both bend radius to duct width ratios were analyzed for Reynolds Number ranging from 50 to 1800. The pressure and velocity distributions were found and used to determine the pressure due to the bend. The results show the pressure loss effect due to the …


Modeling Of Deformed Swept Volumes With Sde And Its Applications To Nc Simulation And Verification, Feng Lu Oct 1997

Modeling Of Deformed Swept Volumes With Sde And Its Applications To Nc Simulation And Verification, Feng Lu

Theses

Representation of swept volumes has important applications in NC simulation and verification as well as robot-motion planning. Most research on .the representation of swept volumes has been limited to rigid objects. In this study, a sweep deferential equation (SDE) approach is presented for the representation of deformed swept volumes generated by flexible objects.

The deformed swept volume analysis is integrated with machining physics to account for tool deformation/deflection for the NC simulation. End milling is modeled and analyzed and the tool deformations are calculated and integrated with the SDE program. A program is developed in C++ for the generation of …


Multi-Lifecycle Assessment Of Cathode Ray Tubes, Devendra Jayant Badwe Oct 1997

Multi-Lifecycle Assessment Of Cathode Ray Tubes, Devendra Jayant Badwe

Theses

Over the past few years environmental issues and concerns have become more and more important, as they become a common part of most people's personal experience. In these regards, the electronics industry is facing substantial problems in terms of end-of-life management of its products, televisions and monitors in particular. The building blocks of this industry are usually viewed as relatively "clean". However, manufacturing by-products of the electronics industry and the disposition of electronics are becoming increasingly important technical, financial, and environmental issues.

Within the context of the above issues, environmentally responsible disposal of Cathode Ray Tubes (CRT's), which is still …


Mechanical Design Of An Experimental Parallel Robot, Philip Song Oct 1997

Mechanical Design Of An Experimental Parallel Robot, Philip Song

Theses

OSCAR, or Operational Space Controlled Adjustable Robot, is a parallel-actuated manipulator, also known as Stewart Platform or platform manipulator. The apparatus consists of two platforms (base and top) and six prismatic actuators in between. The main advantage of a platform manipulator is the fact that it can out-perform serial manipulators in both load capacity and precision. However, there are disadvantages and weaknesses such as limited mobility. A platform manipulator has reduced workspace compared to serial manipulators. The problem of limited workspace is solved by enabling OSCAR to change its prismatic leg positioning about the base platform.

During the course of …


Method And Apparatus For Transferring A Person, Donald J. Smith Jr., Patrick J. Atkinson, Melissa L. Evans, Shawn P. Londo, William J. Ryan Oct 1997

Method And Apparatus For Transferring A Person, Donald J. Smith Jr., Patrick J. Atkinson, Melissa L. Evans, Shawn P. Londo, William J. Ryan

Mechanical Engineering Patents

A method and vehicle preferably a wheelchair (10) for transporting and transferring an invalid person is described. The wheelchair has first and second frames (12 and 48) with drive wheels (18) between which is provided a chair (82) or support (83). The first frame has top and bottom sliding mechanisms (34 and 36) which are mounted by I-beam extensions (38 and 40) to the bars (24 and 26) of the first frame. The second frame has top and bottom rails (54 and 56) which are slidably connected to the sliding mechanisms of the first frame. The rails have slots (78) …


Ole Miss Engineer 1997 Oct 1997

Ole Miss Engineer 1997

Ole Miss Engineer

No abstract provided.


Electrode Performance Test On Single Ceramic Fuel Cells Using As Electrolyte Sr‐ And Mg‐Doped Lagao3, Kevin Huang, Man Feng, John B. Goodenough, Christopher Milliken Oct 1997

Electrode Performance Test On Single Ceramic Fuel Cells Using As Electrolyte Sr‐ And Mg‐Doped Lagao3, Kevin Huang, Man Feng, John B. Goodenough, Christopher Milliken

Faculty Publications

The electrode performance of a single solid oxide fuel cell was evaluated using a 500 μm thick La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) as the electrolyte membrane. Comparison of La0.6Sr0.4CoO3-δ (LSCo) and La0.9Sr0.1MnO3 (LSM) as cathodes showed LSCo gave an exchange current density two orders of magnitude higher than that of LSM. Comparison of CeO2/Ni and LSGM/Ni as anodes showed a degradation of the latter with time, and studies of the anode‐electrolyte interface and the reactivity of NiO and LSGM suggest better anode …


Demonstration Of Cooling Savings Of Light Colored Roof Surfacing In Florida Commercial Buildings: Retail Strip Mall, Florida Solar Energy Center, Danny Parker Oct 1997

Demonstration Of Cooling Savings Of Light Colored Roof Surfacing In Florida Commercial Buildings: Retail Strip Mall, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A series of tests were conducted in seven retail shops in a strip mall in Cocoa, Florida to examine how roof whitening would impact air conditioning load. The roof of the strip mall was conventional: unsurfaced galvanized corrugated metal with R-11 insulation suspended by purlins underneath. Below the insulation was the roof plenum which contained both the air handler and duct air distribution system. Cooling was accomplished in each shop by a dedicated direct expansion air conditioning (AC) system between 3 and 4 tons in size. Each had its air conditioning metered for half of the summer in a baseline …


Photovoltaic Equipment For Disaster Relief, Florida Solar Energy Center, William Young Sep 1997

Photovoltaic Equipment For Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

Photovoltaic (solar electricity) has been used to power various equipment used in disasters. Previously, no organized program had used photovoltaic powered equipment in disasters. In response to an energy needs study with disaster relief organizations, Sandia National Laboratories for the U.S. Department of Energy sponsored the Florida Solar Energy Center to provide PV equipment to selected disaster relief organizations and evaluate its performance and acceptability. The purpose of the report is to describe the six PV-powered systems that were provided.


Controlling Ventilation And Space Depressurization In Restaurants In Hot And Humid Climates, Florida Solar Energy Center, Charles Withers, Jr. Sep 1997

Controlling Ventilation And Space Depressurization In Restaurants In Hot And Humid Climates, Florida Solar Energy Center, Charles Withers, Jr.

FSEC Energy Research Center®

Testing was performed in 9 restaurants to identify uncontrolled air flows and pressure imbalances, building and duct system airtightness, building air barrier location, pressure differentials, building air flow balance, and ventilation rates. All restaurants are depressurized under normal operating conditions, ranging from -1.0 to -43 pascals. Space depressurization is a function of exhaust fan flow rates, missing or undersized make-up air, intermittent outdoor air caused by the cycling of air handlers, dirty outdoor air and make-up air filters, and building airtightness. Ventilation rates were found to be high, generally exceeding ASHRAE 62-1989 minimum recommended levels. Pressure imbalances and excessive ventilation …


Optimization Of Microstructure Development During Hot Working Using Control Theory, James C. Malas Iii, W. Garth Frazier, S. Venugopal, Enrique A. Medina, Steven Madeiros, Raghavan Srinivasan, R. Dennis Irwin, W. M. Mullins, Anil Chaudhary Sep 1997

Optimization Of Microstructure Development During Hot Working Using Control Theory, James C. Malas Iii, W. Garth Frazier, S. Venugopal, Enrique A. Medina, Steven Madeiros, Raghavan Srinivasan, R. Dennis Irwin, W. M. Mullins, Anil Chaudhary

Mechanical and Materials Engineering Faculty Publications

A new approach for controlling microstructure development during hot working processes is proposed. This approach is based on optimal control theory and involves state-space type models for describing the material behavior and the mechanics of the process. The effect of process control parameters such as strain, strain rate, and temperature on important microstructural features can be systematically formulated and then solved as an optimal control problem. This method has been applied to the optimization of grain size and process parameters such as die geometry and ram velocity during the extrusion of plain carbon steel. Experimental results of this investigation show …


High-Frequency Response Of Atomic-Force Microscope Cantilevers, Joseph A. Turner, Sigrun Hirsekorn, Ute Rabe, Walter Arnold Aug 1997

High-Frequency Response Of Atomic-Force Microscope Cantilevers, Joseph A. Turner, Sigrun Hirsekorn, Ute Rabe, Walter Arnold

Department of Engineering Mechanics: Faculty Publications

Recent advances in atomic-force microscopy have moved beyond the original quasistatic implementation into a fully dynamic regime in which the atomic-force microscope cantilever is in contact with an insonified sample. The resulting dynamical system is complex and highly nonlinear. Simplification of this problem is often realized by modeling the cantilever as a one degree of freedom system. This type of first-mode approximation (FMA), or point-mass model, has been successful in advancing material property measurement techniques. The limits and validity of such an approximation have not, however, been fully addressed. In this article, the complete flexural beam equation is examined and …


Flow Due To A Moving Pressure Distribution Over Free-Surface With Finite-Depth Bottom, Noriaki Okita Aug 1997

Flow Due To A Moving Pressure Distribution Over Free-Surface With Finite-Depth Bottom, Noriaki Okita

Masters Theses

Two-dimensional, steady-state and time-dependent analysis of wave making phenomenon due to a moving pressure distribution in sub-critical Froude number was performed. The domain is consisted of undisturbed free-surface at y=0, flat bottom at y=-h, and it is unbounded in horizontal direction. The pressure distribution was treated as an ideal model of an air-cushioned-vehicle (ACV). Ideal flow theory and linearized boundary conditions were used. Numerical integration algorithm was developed to evaluate the analytical solution. The surface elevation, bottom pressure profiles, and wave resistance were analyzed as functions of speed and depth.

The steady-state wave resistance calculated from the surface elevation profile …


Performance Of An Air Conditioning System Using R-134a As A Refrigerant, Abdelrahman I Elsherbini Aug 1997

Performance Of An Air Conditioning System Using R-134a As A Refrigerant, Abdelrahman I Elsherbini

Archived Theses and Dissertations

No abstract provided.


Moving Mountains With Good Research - A Case Study, Florida Solar Energy Center, Ross Mccluney Jul 1997

Moving Mountains With Good Research - A Case Study, Florida Solar Energy Center, Ross Mccluney

FSEC Energy Research Center®

Mountains can be moved by good ideas based on good research. A wonderful example comes to us from, of all things, the Naval Facilities Command (NAVFAC), headquartered in Washington, DC. This agency of the Department of Defense is responsible for some $5 billion per year in new and retrofit construction, with naval facilities all over the globe. The federal government alone is responsible for $50 billion per year of construction, which Terry Emmons of NAVFAC claims is half of total U.S. construction. It seems that the Navy has 120,000 buildings around the world, some buildings, or groupings, are the size …


Batteries And Charge Control In Stand-Alone Photovoltaic Systems, Florida Solar Energy Center, James Dunlop Jul 1997

Batteries And Charge Control In Stand-Alone Photovoltaic Systems, Florida Solar Energy Center, James Dunlop

FSEC Energy Research Center®

This report presents fundamentals of battery technology and charge control strategies commonly used in stand-alone photovoltaic (PV) systems. This work is a compilation of information from several sources, including PV system design manuals, research reports and data from component manufacturers.

Details are provided about the common types of flooded lead-acid, valve regulated lead-acid, and nickel cadmium cells used in PV systems, including their design and construction, electrochemistry and operational performance characteristics. Comparisons are given for various battery technologies, and considerations for battery subsystem design, auxiliary systems, maintenance and safety are discussed.

Requirements for battery charge control in stand-alone PV systems …


Needs Assessment For Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young Jul 1997

Needs Assessment For Applying Photovoltaics To Disaster Relief, Florida Solar Energy Center, William Young

FSEC Energy Research Center®

When disaster strikes, such as a hurricane, flood, tornado, or earthquake, it can leave many people without adequate medical services, portable water, electrical service and communications. It can be as destructive as Hurricane Andrew, which left several hundred-thousand people homeless. Those fortunate enough to survive the disaster could be without local utility power and other services for long periods of time as services are restored.

When such disasters occur, emergency management teams, the military, and many public and private organizations respond with massive relief efforts. Dependency on electrical utility power becomes pronounced as emergency services are rendered and rebuilding begins. …


Energy Efficiency For Florida Educational Facilities: The 1996 Energy Survey Of Florida Schools, Florida Solar Energy Center, Danny Parker Jul 1997

Energy Efficiency For Florida Educational Facilities: The 1996 Energy Survey Of Florida Schools, Florida Solar Energy Center, Danny Parker

FSEC Energy Research Center®

A detailed survey of energy use and related physical and operational characteristics of Florida's public schools has been completed. A mailed survey instrument was sent to all 2,512 schools throughout the state in March 1996. A total of 1, 298 surveys were returned -- a response rate of approximately 52%. Of these some 680 provided matching utility data. The survey data was analyzed to create a school energy use profile as well as to identify characteristics that may influence efficiency. Based on our findings, the total annual energy cost for the Florida school system totaled $205 million in 1995. As …


The Effect Of Residential Equipment Capacity On Energy Use, Demand, And Run-Time, Florida Solar Energy Center, Jo Ellen Cummings Jul 1997

The Effect Of Residential Equipment Capacity On Energy Use, Demand, And Run-Time, Florida Solar Energy Center, Jo Ellen Cummings

FSEC Energy Research Center®

Installed central air conditioning system capacities in 368 recently-built Florida homes were compared with Manual J load values calculated from house audit data. Over 50% of the homes had installed systems with a cooling capacity greater than 120% of the calculated Manual J value. Thirty-one percent of the 78 heat pump homes in this study had installed heating capacity greater than 120% of the calculated Manual J value. Using submetered data from the air conditioning system, a definite increase in peak energy use was observed for systems sized over 120% of Manual J calculations. The effect of system sizing on …


The Study Of Wave-Blocking And Current Effects On Nonlinear Interactions Of Shallow-Water Waves Using Advanced Boussinesq Models, Qin Chen Jul 1997

The Study Of Wave-Blocking And Current Effects On Nonlinear Interactions Of Shallow-Water Waves Using Advanced Boussinesq Models, Qin Chen

Civil & Environmental Engineering Theses & Dissertations

The first part of this work focuses on the derivation of enhanced Boussinesq-type equations for the combined motion of waves and currents in shallow water areas.

The strategy proposed in this work is to couple two known methods which are the sponge layer concept suitable for short waves and Sommerfeld radiation condition for currents. This coupling method provides satisfactory non-reflective boundaries for the simulation of fully coupled wave/current motion as demonstrated by the numerical experiments. We verify the model against the well known solutions based on the existing theories and good agreement has been observed. The numerical results confirm the …


Correlation Of Finite Element Prediction And Experimental Measurements Of Aircraft Panel Structural Vibration, Olaf L. Storaasli Jul 1997

Correlation Of Finite Element Prediction And Experimental Measurements Of Aircraft Panel Structural Vibration, Olaf L. Storaasli

Mechanical & Aerospace Engineering Theses & Dissertations

With the rapid development of computational capabilities and the implementation of complex tools for commercial finite element programs, predicting structural dynamics and related acoustics of complex structures is presently achievable. Structural finite element modeling is a design tool widely utilized for analysis of problems of all kinds. However, high frequency vibration of complex structures, such as the reinforced aircraft panel used for this study, currently does not correlate well with experimental measurements using conventional modeling methods. An investigation into the commonly used modeling techniques as well as the new tools of commercial finite element analysis packages for the prediction of …


Research Related To Multi Degree Of Freedom Magnetic Suspensions, Yan Yang Jul 1997

Research Related To Multi Degree Of Freedom Magnetic Suspensions, Yan Yang

Mechanical & Aerospace Engineering Theses & Dissertations

This thesis covers the activities associated with 1) recommissioning of the 6-inch Magnetic Suspension and Balance System (MSBS) and 2) enhancing the Annular Suspension and Pointing System (ASPS). These activities continue the program of research in the multi degree of freedom magnetic suspension program at Old Dominion University. The 6-inch MSBS is a large gap magnetic suspension system used as a model support and balance system in wind tunnels. The first stage of recommissioning of the 6- inch MSBS for the 6-inch subsonic wind tunnel is performed. Experimental data and computational results for the magnetic field distribution of the MSBS …


Investigation Of Drag Reduction On A Two-Dimensional Circular Cylinder By Ejecting Jet From The Rear Stagnation Region, Satoshi Atsuchi Jul 1997

Investigation Of Drag Reduction On A Two-Dimensional Circular Cylinder By Ejecting Jet From The Rear Stagnation Region, Satoshi Atsuchi

Mechanical & Aerospace Engineering Theses & Dissertations

Extensive work in the field of drag reduction has been done in the past. However, this field of study is highly desirable today because of various high-speed research programs. The present study attempts to investigate the feasibility of drag reduction on a cylinder by flow injection from the rear stagnation region. A two-dimensional circular cylinder at Reynolds number l x105with a jet ejected from its tail is selected as a physical model. To tackle this problem, a numerical simulation as well as an experimental approach were used. Despite the recent development of computational fluid dynamics (CFD), computing a …