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2009

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Residential Water Demand Under Alternative Rate Structures: Simulation Approach, David E. Rosenberg Aug 2009

Residential Water Demand Under Alternative Rate Structures: Simulation Approach, David E. Rosenberg

Civil and Environmental Engineering Faculty Publications

Econometricians have long studied the effect of price on residential water demand and the impact on water use of the rate (tariff) structure in which price signals are embedded. This paper applies an existing deductive model of residential water use for the intermittent supply system in Amman, Jordan and simulates demand responses across a cross section of households over many uniform, increasing block, and linear price (quadratic charge) rate structures at historically low and significantly higher prices. Results show inelastic piped water demand responses for all rate structures at historically low prices similar to findings from a prior econometric study …

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Distance Dependence Of Electron Transfer Kinetics For Azurin Protein Adsorbed To Monolayer Protected Nanoparticle Film Assemblies, Morgan Lynn Vargo, Chris P. Gulka, John K. Gerig, Christopher M. Manieri, Jonathan D. Dattelbaum, Carolyn B. Marks, Nathaniel T. Lawrence, Matthew L. Trawick, Michael C. Leopold Aug 2009

Distance Dependence Of Electron Transfer Kinetics For Azurin Protein Adsorbed To Monolayer Protected Nanoparticle Film Assemblies, Morgan Lynn Vargo, Chris P. Gulka, John K. Gerig, Christopher M. Manieri, Jonathan D. Dattelbaum, Carolyn B. Marks, Nathaniel T. Lawrence, Matthew L. Trawick, Michael C. Leopold

Chemistry Faculty Publications

The distance dependence and kinetics of the heterogeneous electron transfer (ET) reaction for the redox protein azurin adsorbed to an electrode modified with a gold nanoparticle film are investigated using cyclic voltammetry. The nanoparticle films are comprised of nonaqueous nanoparticles, known as monolayer-protected clusters (MPCs), which are covalently networked with dithiol linkers. The MPC film assembly serves as an alternative adsorption platform to the traditional alkanethiolate self-assembled monolayer (SAM) modified electrodes that are commonly employed to study the ET kinetics of immobilized redox proteins, a strategy known as protein monolayer electrochemistry. Voltammetric analysis of the ET kinetics for azurin adsorbed …

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Pointing Control For Low Altitude Triple Cubesat Space Darts , James Armstrong, Craig Casey, Glenn Creamer, Gilbert Dutchover Aug 2009

Pointing Control For Low Altitude Triple Cubesat Space Darts , James Armstrong, Craig Casey, Glenn Creamer, Gilbert Dutchover

Small Satellite Conference

Pointing control of cubesats can be quite challenging due to constraints on volume, cost, and complexity of control hardware. Recent achievements and developments in small sensor and actuator designs have enabled the possibility of reasonable pointing performance (a few degrees or better) for a variety of intriguing space experiments. In this paper we describe a simple pointing control design that exploits the aerodynamics associated with the space dart geometry of a triple cubesat with deployable solar panels in a low-altitude orbit (< 500 km) to provide passive pitch and yaw stabilization, coupled with a small momentum-biased pitch reaction wheel offering passive yaw and roll stabilization. Augmented active rate damping is provided using a small three-axis magnetometer, three small magnetic torquers, and a model-based B-dot control law. This simple passive/active control system offers experiment pointing capability to less than 5 degrees of nadir without the need for any attitude knowledge.

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Mitigating Co2 Production In Coal-To-Liquids Process, Robert Walty Aug 2009

Mitigating Co2 Production In Coal-To-Liquids Process, Robert Walty

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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The Iris Nanosatellite For Autonomous Multi-System Responsive Space Operations And High Spectral Resolution Earth Imaging, Erin Beck, Christopher Kitts, Jose Cruz, Alexander Fischer, Steven Li, Anothony Young Aug 2009

The Iris Nanosatellite For Autonomous Multi-System Responsive Space Operations And High Spectral Resolution Earth Imaging, Erin Beck, Christopher Kitts, Jose Cruz, Alexander Fischer, Steven Li, Anothony Young

Small Satellite Conference

Santa Clara University's Robotic Systems Laboratory is developing the Intelligent Responsive Imaging Spacecraft (IRIS) for autonomous multi-system responsive operations and high spectral resolution Earth imaging. IRIS will interact with an extended system of land, sea, air, and space-based robotic and human elements to observe transient events on the ground. Specifically, IRIS will provide critical imaging and communications services to detect, monitor, and respond to harmful algal blooms in shallow water regions. Students are responsible for all aspects of development. This paper will describe the mission concept and its use of advanced small satellite technologies to perform multi-system responsive space operations.

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Hydrogen In Non-Crystalline Materials: From Solar Cells To Hydrogen Storage, Anatolii Shkrebtii Aug 2009

Hydrogen In Non-Crystalline Materials: From Solar Cells To Hydrogen Storage, Anatolii Shkrebtii

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Hydrogen R&D At Sandia National Labs, Lennie Klebanoff Aug 2009

Hydrogen R&D At Sandia National Labs, Lennie Klebanoff

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Proposed Enhanced Geothermal System Demonstration At The Nevada Test Site, Michael Voegele Aug 2009

Proposed Enhanced Geothermal System Demonstration At The Nevada Test Site, Michael Voegele

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Rapid Coupled Loads Analysis And Spacecraft Load Reduction Using Softride, Raman Johal, Paul Wilke, Conor Johnson Aug 2009

Rapid Coupled Loads Analysis And Spacecraft Load Reduction Using Softride, Raman Johal, Paul Wilke, Conor Johnson

Small Satellite Conference

The dynamic environment that a spacecraft will experience during a launch is unknown until a full coupled loads analysis (CLA) has been performed by the launch vehicle contractor. By the time this has been done, the small satellite provider might not have time to mitigate problem areas by redesigning component mounts or alternatively installing isolating mounts. Unmitigated loads issues could increase the risk of failure of not only a component, but of the entire mission. This current process of mission planning is costly and inefficient. A better approach is to have coupled loads analysis data available for real spacecraft of …

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Unlv Solar And Renewable Energy Minor, Thomas C. Piechota Aug 2009

Unlv Solar And Renewable Energy Minor, Thomas C. Piechota

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Thin Wire Nucleate Boiling Of Water In Sustained Microgravity, Justin Koeln Aug 2009

Thin Wire Nucleate Boiling Of Water In Sustained Microgravity, Justin Koeln

Small Satellite Conference

The advancement of small satellite technology relies on the development of effective thermal management systems that can be made smaller, safer, and more robust. This paper presents the results and analysis of a nucleate boiling experiment in sustained microgravity aboard the Space Shuttle Endeavor (STS-108). Bubble growth and departure were observed from a single and a braid of three 0.16 mm diameter and 80 mm long nickel-chromium resistive wires. Analysis showed that the braided wire provides a unique surface configuration to enhance the onset of boiling. The braid of wires was also observed to produce several bubble explosions; this is …

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Microalgae For Biodiesel, Co2 Capture, And Wastewater Treatment, Jian Ma Aug 2009

Microalgae For Biodiesel, Co2 Capture, And Wastewater Treatment, Jian Ma

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Cryogenic Experimentation On The Magnetohydrodynamics Of Liquid Oxygen, Jeffrey Boulware Aug 2009

Cryogenic Experimentation On The Magnetohydrodynamics Of Liquid Oxygen, Jeffrey Boulware

Small Satellite Conference

The increasing demands of the small satellite industry are forcing the development of subsystems with increased reliability and robustness while maintaining harsh mass and volume constraints. Basic research has begun on the cryogenic magnetohydrodynamic properties of liquid oxygen to determine its feasibility as a working fluid in a magnetic system void of mechanically moving parts. A 1D finite-differenced numerical algorithm verified experimental data on the dynamics of a liquid oxygen slug propagated by pulsed magnetic fields. Up to 1.4 T was induced by electrically-sequenced solenoids wound with 30 gauge copper wire. The test section consisted of two solenoids and a …

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Sattherm: A Thermal Analysis And Design Tool For Small Spacecraft , Cassandra Allison, Millan Diaz-Aguado, Belgacem Jaroux Aug 2009

Sattherm: A Thermal Analysis And Design Tool For Small Spacecraft , Cassandra Allison, Millan Diaz-Aguado, Belgacem Jaroux

Small Satellite Conference

Small spacecraft have become an attractive alternative for a significant class of space missions. They have the potential to provide valuable science data with shorter development times and at a reduced cost over traditional multi-instrument spacecraft. However, many of the legacy tools used for spacecraft design and analysis have considerable cost and complexity that are not suited to small spacecraft and their associated short development cycles. SatTherm is an alternative thermal analysis tool specifically developed for small spacecraft as a collaborative effort between the Mission Design Center at NASA Ames and San Jose State University. It is intended to be …

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Overview Of Dri’S Renewable Energy Activities, Kent Hoekman Aug 2009

Overview Of Dri’S Renewable Energy Activities, Kent Hoekman

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Nshe's Nevada Renewable Energy Consortium, Steve Wells Aug 2009

Nshe's Nevada Renewable Energy Consortium, Steve Wells

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance

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Coe And Sri Collaborate To Improve Middle School Math, August 12, 2009, Melanie Marquez Aug 2009

Coe And Sri Collaborate To Improve Middle School Math, August 12, 2009, Melanie Marquez

USF St. Petersburg Campus News and Press Releases

No abstract provided.

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Analysis Of Induced Vibrations In Fully-Developed Turbulent Pipe Flow Using A Coupled Les And Fea Approach, Thomas P. Shurtz Aug 2009

Analysis Of Induced Vibrations In Fully-Developed Turbulent Pipe Flow Using A Coupled Les And Fea Approach, Thomas P. Shurtz

Theses and Dissertations

Turbulent flow induced pipe vibration is a phenomenon that has been observed but not fully characterized. This thesis presents research involving numerical simulations that have been used to characterize pipe vibration resulting from fully developed turbulent flow. The vibration levels as indicated by: pipe surface displacement, velocity, and acceleration are characterized in terms of the parameters that exert influence. The influences of geometric and material properties of the pipe are investigated for pipe thickness in the range 1 to 8 mm at a diameter of 0.1015 m. The effects of pipe elastic modulus are explored from 3 to 200 GPa. …

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Piezoresistive Models For Polysilicon With Bending Or Torsional Loads, Gerrit T. Larsen Aug 2009

Piezoresistive Models For Polysilicon With Bending Or Torsional Loads, Gerrit T. Larsen

Theses and Dissertations

This thesis presents new models for determining piezoresistive response in long, thin polysilicon beams with either axial and bending moment inducing loads or torsional loads. Microelectromechanical (MEMS) test devices and calibration methods for finding the piezoresistive coefficients are also presented for both loading conditions. For axial and bending moment inducing loads, if the piezoresistive coefficients are known, the Improved Piezoresistive Flexure Model (IPFM) is used to find the new resistance of a beam under stress. The IPFM first discretizes the beam into small volumes represented by resistors. The stress that each of these volumes experiences is calculated, and the stress …

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Development Of Biocompatible Polymer Monoliths For The Analysis Of Proteins And Peptides, Yun Li Aug 2009

Development Of Biocompatible Polymer Monoliths For The Analysis Of Proteins And Peptides, Yun Li

Theses and Dissertations

Biocompatibility is an important issue for the development of chromatographic stationary phases for the analysis of biomolecules (including proteins and peptides). A biocompatible stationary phase material is a material that resists nonspecific adsorption of biomolecules and does not interact with them in a way that would alter or destroy their structures or biochemical functions. The monolithic column format is a good alternative to typical spherical particle packed columns for capillary liquid chromatography of biomacromolecules. Several novel anion-exchange polymer monoliths for the analysis of proteins were synthesized for improved biocompatibility. Two novel polymeric monoliths were prepared in a single step by …

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Functional Near-Infrared Spectroscopy For Hb And Hbo₂ Detection Using Remote Sensing, Rane M. Pierson Aug 2009

Functional Near-Infrared Spectroscopy For Hb And Hbo₂ Detection Using Remote Sensing, Rane M. Pierson

Theses and Dissertations

The goal of the work presented in this thesis is to develop a wireless, near-infrared (NIR) imaging system to provide flexibility and functionality to clinicians and researchers who require monitoring of blood profusion to tissue, muscles, or the brain. The prototype device uses a single stimulus/detection unit composed of an Epitex NIR LED with three wavelength options: 730, 805, and 850 nm, and an OPT101 photodiode detector. The device can be used to detect changes in the levels of oxygenated and deoxygenated hemoglobin in the body by measuring the amounts of absorbed and backscattered light at the wavelength associated with …

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Ben Griffin Oral History Interview, Ben Griffin Aug 2009

Ben Griffin Oral History Interview, Ben Griffin

Otis R. Anthony African Americans in Florida Oral History Project

This is a transcript of an oral history interview with Ben Griffin, a teacher and school administrator, in which he describes the conditions in segregated schools and discusses the events leading to integration, recounting some of the problems faced.

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Isogeometric Finite Element Analysis Using T-Splines, Jingang Li Aug 2009

Isogeometric Finite Element Analysis Using T-Splines, Jingang Li

Theses and Dissertations

Non-uniform rational B-splines (NURBS) methodology is presented, on which the isogeometric analysis is based. T-splines are also introduced as a surface design methodology, which are a generalization of NURBS and permit local refinement. Isogeometric analysis using NURBS and T-splines are applied separately to a structural mechanics problem. The results are compared with the closed-form solution. The desirable performance of isogeometric analysis using T-splines on engineering analysis is demonstrated.

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2009 Fall Convocation Program, Office Of Communications & Marketing, Morehead State University. Aug 2009

2009 Fall Convocation Program, Office Of Communications & Marketing, Morehead State University.

Communications and Marketing Publications Archive

Fall convocation program held on August 12, 2009.

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3dwheel: 3-Axis Low Noise, High-Bandwidth Attitude Actuation From A Single Momentum Wheel Using Magnetic Bearings, Jon Seddon, Alexandre Pechev Aug 2009

3dwheel: 3-Axis Low Noise, High-Bandwidth Attitude Actuation From A Single Momentum Wheel Using Magnetic Bearings, Jon Seddon, Alexandre Pechev

Small Satellite Conference

This paper proposes a new concept for attitude actuation for small satellites that uses active magnetic bearings to support and tilt a spinning rotor to provide 3-axis attitude control of the satellite using a single actuator. A controlled 3D motion in the spinning rotor provides a conventional torque output about the momentum axis and a gyroscopic torque output about any direction in the plane normal to the spinning axis. Therefore, a single tilting momentum-wheel can generate torque along the three principal axes of the satellite, providing mass and power savings, or redundancy. In this paper we present a model of, …

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Current Projects At The Unlv Center For Energy Research, Robert F. Boehm Aug 2009

Current Projects At The Unlv Center For Energy Research, Robert F. Boehm

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Calibration Techniques For Low-Cost Star Trackers, Tom Dzamba, John Enright Aug 2009

Calibration Techniques For Low-Cost Star Trackers, Tom Dzamba, John Enright

Small Satellite Conference

This study presents a series of cost-e_ective strategies for calibrating star trackers for microsatellite missions. We examine three such strategies that focus on the calibration of the imaging detector, geometric lab calibration, and optical calibration due to lens aberrations. Procedures are developed that emphasize speed of implementation, and accuracy, while trying to minimize manual setup procedures. Preliminary results show that employing existing camera calibration techniques reduces the variation in pixel sensitivity by approximately 10%, averaged across each pixel color given the use of a color imager. Although not substantial, this reduction in pixel variation helps preserve the Gaussian illumination pattern …

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Education And Energy Innovation: Nshe’S Central Role In Transforming Nevada’S Economy, James Croce Aug 2009

Education And Energy Innovation: Nshe’S Central Role In Transforming Nevada’S Economy, James Croce

UNLV Renewable Energy Symposium

The 3rd Annual Renewable Energy Symposium took place on the UNLV campus August 11 & 12. The event focused on renewable energy production in Nevada, the US Southwest, and renewable research projects nationwide. The event was a great success with over 200 individuals in attendance.

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Delfi-C3 Preliminary Mission Results , Robbert Hamann, Jasper Bouwmeester, Geert Brouwer Aug 2009

Delfi-C3 Preliminary Mission Results , Robbert Hamann, Jasper Bouwmeester, Geert Brouwer

Small Satellite Conference

Delfi-C3 is a three-unit CubeSat launched on April 28th 2008 and has been designed, developed and operated by students of the Delft University of Technology and several Engineering Colleges in the Netherlands. Preliminary results of the Thin Film Solar Cell and Autonomous Wireless Sun Sensor payloads are shown and discussed, as well as the experiences with a third on-board experiment: a transponder for the radio amateur community.In the first three months of operations Delfi-C3 has collected 53,000 high quality current-voltage curves of the solar cells (1.3% of the maximum possible) and has performed some 3,500 attitude measurements with the Sun …

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Bx-1: The Companion Microsatellite In Shenzhou-7 Mission, Zhencai Zhu, Hongyu Chen, Wen Chen, Yilin Zhou, Yong Yu, Caixia Cao Aug 2009

Bx-1: The Companion Microsatellite In Shenzhou-7 Mission, Zhencai Zhu, Hongyu Chen, Wen Chen, Yilin Zhou, Yong Yu, Caixia Cao

Small Satellite Conference

Microsatellites flying around big spacecraft can provide security monitoring for spacecrafts, extend mission functions, and provide an ideal platform for demonstrating and verifying key technologies of coordinated space missions. Most companion satellites have orbit manoeuvre capability. They usually take space station, aircraft, piloted spaceship, big satellite or other big spacecraft as task centre or service object, and fly with it in a certain relative formation. The BX-1 micro-satellite is the companion satellite for the Shenzhou VII (SZ-7) manned spaceship and carries out two in-orbit experiments in the Shenzhou VII mission: images capturing of SZ-7 and the companion flying experiment. The …

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