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Improved Computational And Experimental Validation Using Different Turbulence Models, Jay Marcos, David D. Marshall 2011 California Polytechnic State University - San Luis Obispo

Improved Computational And Experimental Validation Using Different Turbulence Models, Jay Marcos, David D. Marshall

David D. Marshall

This paper will explore the methods and techniques necessary to perform a more accurate CFD validation of experimental results. The methods and techniques used will be validated against experimental wind tunnel data of a 2D high lift airfoil with a 3D engine performed by Georgia Tech Research Institute. Preliminary results showed that computational methods over predict the lift and drag coefficient, while still showing very similar trends in CL and CD. To further improve the preliminary results and the predictive capabilities, different turbulence models will be investigated. Results of this validation will assist in determining the appropriate turbulence models, boundary ...


The Effects Of Humidity On The Dielectric Response In Ferroelectric Polymer Films Made By Langmuir-Blodgett Deposition, Kristin Kraemer, Alexander Sorokin, Christina Othon, Stephen Ducharme, Vladimir Fridkin 2011 University of Nebraska at Lincoln

The Effects Of Humidity On The Dielectric Response In Ferroelectric Polymer Films Made By Langmuir-Blodgett Deposition, Kristin Kraemer, Alexander Sorokin, Christina Othon, Stephen Ducharme, Vladimir Fridkin

Christina M Othon

No abstract provided.


Electron Irradiation Effects On Ferroelectric Copolymer Langmuir-Blodgett Films, Christina M. Othon, Stephen Ducharme 2011 University of Nebraska-Lincoln

Electron Irradiation Effects On Ferroelectric Copolymer Langmuir-Blodgett Films, Christina M. Othon, Stephen Ducharme

Christina M Othon

The effect of irradiation on the ferroelectric properties of Langmuir-Blodgett films of the copolymer poly(vinylidene fluoride-trifluorethelene) is investigating using 1.26 MeV electrons with dosages from 16 to 110 Mrad. Irradiation causes a systematic decrease in the phase transition temperature, coercive field and polarization of these thin films.


Improved 3-Omega Measurement Of Thermal Conductivity In Liquid, Gases, And Powders Using A Metal-Coated Optical Fiber, Scott N. Schiffres, Jonathan A. Malen 2011 Carnegie Mellon University

Improved 3-Omega Measurement Of Thermal Conductivity In Liquid, Gases, And Powders Using A Metal-Coated Optical Fiber, Scott N. Schiffres, Jonathan A. Malen

Department of Mechanical Engineering

A novel 3ωthermal conductivitymeasurement technique called metal-coated 3ω is introduced for use with liquids, gases, powders, and aerogels. This technique employs a micron-scale metal-coated glass fiber as a heater/thermometer that is suspended within the sample. Metal-coated 3ω exceeds alternate 3ω based fluid sensing techniques in a number of key metrics enabling rapid measurements of small samples of materials with very low thermal effusivity (gases), using smaller temperature oscillations with lower parasitic conduction losses. Its advantages relative to existing fluid measurement techniques, including transient hot-wire, steady-state methods, and solid-wire 3ω are discussed. A generalized ...


Kinematic Cartography For Locomotion At Low Reynolds Numbers, Ross L. Hatton, Howie Choset 2011 Carnegie Mellon University

Kinematic Cartography For Locomotion At Low Reynolds Numbers, Ross L. Hatton, Howie Choset

Robotics Institute

Kinematic motion planning often requires a notion of distance between configurations. Euclidean distances on a parameter space are easy to compute, but can drastically distort the effort required to change configuration. Here, we present a framework for characterizing this distortion, based on principles adopted from the cartographic community, and a method for transforming configuration coordinates to better represent actuation costs. As a demonstration of this approach, we derive a true configuration distance metric for an important class of locomoting systems: low Reynolds number swimmers. Applying our cartographic coordinate transformation to these systems both provides intuition for previous numerical results, and ...


Learning Message-Passing Inference Machines For Structured Prediction, Stephane Ross, Daniel Munoz, Martial Hebert, J. Andrew Bagnell 2011 Carnegie Mellon University

Learning Message-Passing Inference Machines For Structured Prediction, Stephane Ross, Daniel Munoz, Martial Hebert, J. Andrew Bagnell

Robotics Institute

Nearly every structured prediction problem in computer vision requires approximate inference due to large and complex dependencies among output labels. While graphical models provide a clean separation between modeling and inference, learning these models with approximate inference is not well understood. Furthermore, even if a good model is learned, predictions are often inaccurate due to approximations. In this work, instead of performing inference over a graphical model, we instead consider the inference procedure as a composition of predictors. Specifically, we focus on message-passing algorithms, such as Belief Propagation, and show how they can be viewed as procedures that sequentially predict ...


Active Management Of A Heterogeneous Energy Store For Electric Vehicles, Alexander Styler, Gregg Podnar, Paul Dille, Matthew Duescher, Chris Bartley, Illah Nourbakhsh 2011 Carnegie Mellon University

Active Management Of A Heterogeneous Energy Store For Electric Vehicles, Alexander Styler, Gregg Podnar, Paul Dille, Matthew Duescher, Chris Bartley, Illah Nourbakhsh

Robotics Institute

The successful introduction of electric vehicles continues to be stifled by the high cost and limited perfor-mance life of battery technology. We assert that a disruptive improvement in systems-level cost-of-performance is possible by employing a rate-heterogeneous energy storage system, combining low-rate batteries and high-rate supercapacitors, that is mated to a predictive control system that optimizes power management by exploiting topographic information, traffic history, and specific driver performance. Such predictive power management, optimizing energy storage throughout episodes of vehicle acceleration and regenerative braking, has the potential to significantly decrease the total energy duty on the vehicle’s batteries.


Perception And Control Challenges For Effective Human-Robot Handoffs, Vincenzo Micelli, Kyle Strabala, Siddhartha Srinivasa 2011 University of Parma

Perception And Control Challenges For Effective Human-Robot Handoffs, Vincenzo Micelli, Kyle Strabala, Siddhartha Srinivasa

Robotics Institute

Human-robot handoffs are a primary task for a personal robot. Previously, robots put the majority of the handoff burden on the human, where in the case of the human to robot handoff the human had to position and orient the object into the robot’s hand. This works well because it is a very easy task for humans, but what happens if humans handoff objects while they are distracted or if they have some impairment? Is the handoff still possible? The recent arrival of reliable human-tracking systems like the Kinect and smart control algorithms that use the human-tracking feedback and ...


Computational Rationalization: The Inverse Equilibrium Problem, Kevin Waugh, Brian D. Ziebart, J. Andrew Bagnell 2011 Carnegie Mellon University

Computational Rationalization: The Inverse Equilibrium Problem, Kevin Waugh, Brian D. Ziebart, J. Andrew Bagnell

Robotics Institute

Modeling the purposeful behavior of imperfect agents from a small number of observations is a challenging task. When restricted to the single-agent decision-theoretic setting, inverse optimal control techniques assume that observed behavior is an approximately optimal solution to an unknown decision problem. These techniques learn a utility function that explains the example behavior and can then be used to accurately predict or imitate future behavior in similar observed or unobserved situations. In this work, we consider similar tasks in competitive and cooperative multi-agent domains. Here, unlike single-agent settings, a player cannot myopically maximize its reward --- it must speculate on how ...


From 3d Scene Geometry To Human Workspace, Abhinav Gupta, Scott Satkin, Alexei Efros, Martial Hebert 2011 Carnegie Mellon University

From 3d Scene Geometry To Human Workspace, Abhinav Gupta, Scott Satkin, Alexei Efros, Martial Hebert

Robotics Institute

We present a human-centric paradigm for scene understanding. Our approach goes beyond estimating 3D scene geometry and predicts the "workspace" of a human which is represented by a data-driven vocabulary of human interactions. Our method builds upon the recent work in indoor scene understanding and the availability of motion capture data to create a joint space of human poses and scene geometry by modeling the physical interactions between the two. This joint space can then be used to predict potential human poses and joint locations from a single image. In a way, this work revisits the principle of Gibsonian affordances ...


Navigation And Control For Micro Aerial Vehicles In Gps-Denied Environments, Rudolph Molero, Sebastian Scherer, Lyle J. Chamberlain, Sanjiv Singh 2011 Carnegie Mellon University

Navigation And Control For Micro Aerial Vehicles In Gps-Denied Environments, Rudolph Molero, Sebastian Scherer, Lyle J. Chamberlain, Sanjiv Singh

Robotics Institute

Micro-air vehicles have been increasingly employed in diverse research projects in both military and civilian applications. That is because their high maneuverability and accurate mobility. Many of them have been successfully used in outdoor areas, while some have been operated indoors. However, very few have dedicated especial attention to the case of high pitch and roll movements while doing scan-line based odometry. In this paper, we present a general approach consisting of algorithms that enable small aerial robots to fly indoors. We solve the overall problem of large movement change in pitch and roll angles by improving the standard scan ...


Symmetry-Adapted Non-Equilibrium Molecular Dynamics Of Chiral Carbon Nanotubes Under Tensile Loading, Amin Aghaei, Kaushik Dayal 2011 Carnegie Mellon University

Symmetry-Adapted Non-Equilibrium Molecular Dynamics Of Chiral Carbon Nanotubes Under Tensile Loading, Amin Aghaei, Kaushik Dayal

Department of Civil and Environmental Engineering

We report on non-equilibrium molecular dynamics calculations of chiral single-wall carbon nanotubes using the framework of Objective Structures. This enables us to adapt molecular dynamics to the symmetry of chiralnanotubes and efficiently simulate these systems with small unit cells. We outline the method and the adaptation of a conventional thermostat and barostat to this setting. We then apply the method in order to examine the behavior of nanotubes with various chiralities subject to a constant extensional strain rate. We examine the effects of temperature, strain rate, and pre-compression/pre-tension. We find a range of failure mechanisms, including the formation of ...


Linking Cyclic Stress And Cyclic Strain Based Methods For Assessment Of Cyclic Liquefaction Triggering In Sands, J. A. Schneider, R. E.S. Moss 2011 University of Wisconsin - Madison

Linking Cyclic Stress And Cyclic Strain Based Methods For Assessment Of Cyclic Liquefaction Triggering In Sands, J. A. Schneider, R. E.S. Moss

Civil and Environmental Engineering

Contradictory conclusions may arise when assessing liquefaction resistance of sands based on penetrat1on tests and shear wave velocity. To provide a more unified analysis framework, th1s letter couples cyclic stress and cyclic strain based analysis of liquefaction triggering using site-specific correlations between penetration resistance and small strain shear modulus from shear wave velocity using the seismic cone tests. Cyclic strain theory provides a robust lower limit to liquefaction resistance, and analyses indicate that relatively high ratios of small strain stiffness to penetration resistance lead to high liquefaction resistance at relatively low cyclic stress ratios_ The increased resistance to liquefaction from ...


Analysis And Design Of An Affordable High Altitude Rocket System, Brian Cooper 2011 California Polytechnic State University - San Luis Obispo

Analysis And Design Of An Affordable High Altitude Rocket System, Brian Cooper

Aerospace Engineering

This paper discusses the design of the Rarefied High-Altitude Zenith Experimental Rocket (RHAZER) which is launched at an altitude of 35 kilometers from a weather balloon. The weather balloon is capable of carrying up to 2 kilograms of payload to this altitude, and the rocket can carry a payload of approximately 150 grams to an altitude of at least 80 kilometers and be recovered safely after landing. It is designed to be aerodynamically stable at its launch point, while using fins to spin-stabilize before it enters the low-pressure upper atmosphere. This system has been designed to be used as an ...


Preview, Exercise, Teaching And Learning In Digital Electronics Education, Guoping Wang 2011 Indiana University - Purdue University Fort Wayne

Preview, Exercise, Teaching And Learning In Digital Electronics Education, Guoping Wang

Engineering Faculty Publications

Through multimedia delivery of new materials, web-based warm-up exercises and interactiveclassroom teaching/learning, this paper presents a new teaching approach - PETL (Preview,Exercise, Teaching and Learning) in teaching and learning digital electronics. Different from thetraditional recitation-based lecture formats, the proposed pedagogy is a teaching and learningstrategy based on the active participation of learners at each stage of the learning process, namely,preview of new topics, web-based warm-up assignments, and interactive classroom teaching andlearning. Students briefly preview the new materials delivered through web-based multimedia, andthen respond electronically to carefully constructed warm-up exercises which are due before class.The instructor reviews students ...


The Effectiveness Of Virtual R&D Teams In Smes: Experiences Of Malaysian Smes, Nader Ale Ebrahim, Salwa Hanim Abdul Rashid, Shamsuddin Ahmed, Zahari Taha 2011 Department of Engineering Design and Manufacture, Faculty of Engineering, University of Malaya

The Effectiveness Of Virtual R&D Teams In Smes: Experiences Of Malaysian Smes, Nader Ale Ebrahim, Salwa Hanim Abdul Rashid, Shamsuddin Ahmed, Zahari Taha

Nader Ale Ebrahim

The number of small and medium enterprises (SMEs), especially those involved with research and development (R&D) programs and employed virtual teams to create the greatest competitive advantage from limited labor are increasing. Global and localized virtual R&D teams are believed to have high potential for the growth of SMEs. Due to the fast-growing complexity of new products coupled with new emerging opportunities of virtual teams, a collaborative approach is believed to be the future trend. This research explores the effectiveness of virtuality in SMEs’ virtual R&D teams. Online questionnaires were emailed to Malaysian manufacturing SMEs and 74 ...


Development And Design Of A Hovering Controller For Operation In A Dynamic Asteroid Environment, Nicholas Georgiades 2011 California Polytechnic State University - San Luis Obispo

Development And Design Of A Hovering Controller For Operation In A Dynamic Asteroid Environment, Nicholas Georgiades

Aerospace Engineering

The project seeks to develop a dynamic model similar to that present near a solar system small body, and to design a controller suggested in other resources that will allow a spacecraft operating in this environment to hover in a fixed location in the relative reference frame of the small body. The paper discusses the derivation of the equations of motion used in the non-linear dynamic model, the design of the controller that will allow the spacecraft to hover, and the development of the control loop that will simulate the spacecraft hovering in the dynamic environment of the asteroid 1999 ...


Design And Cost Analysis Of A Citrus Orchard, Travis Cox 2011 California Polytechnic State University - San Luis Obispo

Design And Cost Analysis Of A Citrus Orchard, Travis Cox

BioResource and Agricultural Engineering

No abstract provided.


The Columbia City Trailhead: A Collaborative Construction Engineering Technology Capstone Experience, Barry Dupen, Regina Leffers 2011 Indiana University - Purdue University Fort Wayne

The Columbia City Trailhead: A Collaborative Construction Engineering Technology Capstone Experience, Barry Dupen, Regina Leffers

Manufacturing and Construction Engineering Technology Faculty Publications

In 2010, a collaborative effort between a nonprofit trail advocacy organization, a small rural Indiana city, trade unions, grantmaking organizations, materials suppliers, contractors, and the Construction Engineering Technology program at Indiana University – Purdue University Fort Wayne (IPFW) led to the successful construction of a trailhead building in a city park. Multidisciplinary collaboration began with a design charrette in January, bringing together architects, brickmasons, carpenters, electricians, engineers, greenbuilding experts, landscapers, professors, and students. Starting with a site plan by a local architect and a construction blueprint from another trailhead elsewhere in the state, charrette participants improved the design and site location ...


An Analysis Of N-Body Trajectory Propagation, Emerson Frees II 2011 California Polytechnic State University - San Luis Obispo

An Analysis Of N-Body Trajectory Propagation, Emerson Frees Ii

Aerospace Engineering

Trajectories created with n-body orbit models were propagated in geocentric and interplanetary test cases. The n-body models were created in MATLAB® using numerical integration. In the geocentric test case, the n-body codes were compared to a two-body orbit model and to the default HPOP model used in Satellite Tool Kit®. The interplanetary test case compared the n-body model to the HORIZONS ephemeris data from JPL and an equation for ephemeris propagation. Both cases used the same initial positions and velocities and were propagated for the same duration. The results of the analysis showed that while n-body models are capable of ...


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