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Data Protection Models For Service Provisioning In The Cloud, Dan Lin, Anna Squicciarini Jul 2010

Data Protection Models For Service Provisioning In The Cloud, Dan Lin, Anna Squicciarini

Computer Science Faculty Research & Creative Works

Cloud computing enables highly scalable services to be easily consumed over the Internet on an as-needed basis. While cloud computing is expanding rapidly and used by many individuals and organizations internationally, data protection issues in the cloud have not been carefully addressed at current stage. in the cloud, users' data is usually processed remotely in unknown machines that users do not own or operate. Hence, users' fear of confidential data (particularly financial and health data) leakage and loss of privacy in the cloud becomes a significant barrier to the wide adoption of cloud services. to allay users' concerns of their …

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Electric Field-Free Gas Breakdown In Explosively Driven Generators, S. I. Shkuratov, Jason Baird, E. F. Talantsev, Larry L. Altgilbers Jul 2010

Electric Field-Free Gas Breakdown In Explosively Driven Generators, S. I. Shkuratov, Jason Baird, E. F. Talantsev, Larry L. Altgilbers

Mining Engineering Faculty Research & Creative Works

All known types of gas discharges require an electric field to initiate them. We are reporting on a unique type of gas breakdown in explosively driven generators that does not require an electric field.

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Dynamic Placement And Signal Selection For Upfcs In Wide-Area Controlled Power Systems, Mahyar Zarghami, Mariesa Crow Jul 2010

Dynamic Placement And Signal Selection For Upfcs In Wide-Area Controlled Power Systems, Mahyar Zarghami, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

This paper deals with the problem of damping inter-area oscillations in wide-area bulk power systems using unified power flow controllers. Dynamic placement and signal selection are two important issues when FACTS devices are deployed in the system. in the paper both problems have been investigated using a Most Dominant Branches table calculated based on modal analysis which shows the influence of active powers of the branches on inter-area modes of the system. First, dynamic placement has been explained in which the best placement candidates are selected based on their influence on inter-area modes. Next the paper deals with dynamic estimation …

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Environmental Obfuscation Of A Cyber Physical System - Vehicle Example, Jason Madden, Bruce M. Mcmillin, Anik Sinha Jul 2010

Environmental Obfuscation Of A Cyber Physical System - Vehicle Example, Jason Madden, Bruce M. Mcmillin, Anik Sinha

Computer Science Faculty Research & Creative Works

Cyber-Physical Systems (CPSs) are deeply embedded infrastructures that have significant cyber and physical components that interact with each other in complex ways. These interactions can violate a system's security policy, leading to unintended information flow. The physical portion of such systems is inherently observable, and, as such, many methods of preserving confidentiality are not applicable. This fundamental property of CPSs presents new security challenges. To illustrate this, a vehicle composed of an embedded computer system, its operator, and its environment show how information is disclosed to an observer that is watching from the outside. The example is made of up …

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Room-Temperature Protonic Conduction In Nanocrystalline Films Of Yttria-Stabilized Zirconia, Hugo J. Avila-Paredes, Enrique Barrera-Calva, Harlan U. Anderson, Roger A. De Souza, Manfred Martin, Zuhair A. Munir, Sangtae Kim Jul 2010

Room-Temperature Protonic Conduction In Nanocrystalline Films Of Yttria-Stabilized Zirconia, Hugo J. Avila-Paredes, Enrique Barrera-Calva, Harlan U. Anderson, Roger A. De Souza, Manfred Martin, Zuhair A. Munir, Sangtae Kim

Materials Science and Engineering Faculty Research & Creative Works

We report the results of our investigation on protonic conduction in 1 µm-thick polycrystalline films of 8 mol% yttria-stabilized zirconia (YSZ) with an average grain size of 17 nm prepared on sapphire substrate using a spin-coating process. Protonic conductivity of the films is found to be higher by over an order of magnitude (at 30 °C) than earlier reported values for nanocrystalline YSZ bulk ceramics with a similar grain size. This value is comparable to the oxygen-ionic conductivity of this material presented at about 400 °C. These results suggest that, besides grain size, the structural characteristics of the grain boundaries …

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Cyber-Physical Codesign Of Distributed Structural Health Monitoring With Wireless Sensor Networks, Gregory Hackmann, Weijun Guo, Guirong Yan, Chenyang Lu, Shirley Dyke Jul 2010

Cyber-Physical Codesign Of Distributed Structural Health Monitoring With Wireless Sensor Networks, Gregory Hackmann, Weijun Guo, Guirong Yan, Chenyang Lu, Shirley Dyke

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Our Deteriorating Civil Infrastructure Faces the Critical Challenge of Long-Term Structural Health Monitoring for Damage Detection and Localization. in Contrast to Existing Research that Often Separates the Designs of Wireless Sensor Networks and Structural Engineering Algorithms, This Paper Proposes a Cyber-Physical Co-Design Approach to Structural Health Monitoring based on Wireless Sensor Networks. Our Approach Closely Integrates (1) Flexibility-Based Damage Localization Methods that Allow a Tradeoff between the Number of Sensors and the Resolution of Damage Localization, and (2) an Energy-Efficient, Multi-Level Computing Architecture Specifically Designed to Leverage the Multi-Resolution Feature of the Flexibility-Based Approach. the Proposed Approach Has Been Implemented …

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Low Viscosity Pore Fluid To Manufacture Transparent Soil, Honghua Zhao, Louis Ge, Ronaldo Luna Jul 2010

Low Viscosity Pore Fluid To Manufacture Transparent Soil, Honghua Zhao, Louis Ge, Ronaldo Luna

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Transparent soil has been investigated for its potential as a substitute research media for natural soil. the mechanism for manufacturing the transparent soil is through adding an appropriate pore fluid to silica gel particles with the same refractive index. Two types of high viscosity pore fluids were identified by Iskander in 1994. However, because of the high viscosity of these two pore fluids, air was easily entrapped, which made the manufacture of a large mass of transparent soil difficult. in addition, the identified pore fluids caused serious membrane deterioration during triaxial laboratory testing. This research presented herein is an experimental …

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Intelligent Computational Argumentation For Evaluating Performance Scores In Multi-Criteria Decision Making, Xiaoqing Frank Liu, Rubal Wanchoo, Ravi Santosh Arvapally Jul 2010

Intelligent Computational Argumentation For Evaluating Performance Scores In Multi-Criteria Decision Making, Xiaoqing Frank Liu, Rubal Wanchoo, Ravi Santosh Arvapally

Computer Science Faculty Research & Creative Works

Multi-Criteria decision making (MCDM), is a discipline aimed at assisting multiple stakeholders in contemplating a decision paradigm in an uncertain environment. the decision analysis to be performed involves numerous alternative positions assessed under varied criterion. a performance score is assigned for each alternative in terms of every criterion, and it represents satisfaction of the criteria by that alternative. in real applications, performance scores are sometimes hard to determine, and they are often subjective. We have developed an intelligent computational argumentation approach for dealing with the problem of uncertainty in resolving the subjective scores. in this approach, an argumentation tree is …

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A Hotspot-Based Protocol For Attack Traceback In Mobile Ad Hoc Networks, Hungyuan Hsu, Sencun Zhu, Ali Hurson Jul 2010

A Hotspot-Based Protocol For Attack Traceback In Mobile Ad Hoc Networks, Hungyuan Hsu, Sencun Zhu, Ali Hurson

Electrical and Computer Engineering Faculty Research & Creative Works

based on the principle of divide and conquer, in this paper we propose an efficient traceback protocol for mobile ad hoc networks, the protocol is capable of detecting a hotspot where the attacker resides. It works by dividing the forwarding path of every packet into multiple interweaving fragments and each reachable fragment is individually reconstructed during a traceback process. through simulations in theoretical mobility models as well as real mobility traces, we show that each traceback of our scheme can attribute to a very small hotspot and the attacker can be accurately identified after a number of traceback operations. © …

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Investigations Of Femtosecond-Nanosecond Dual-Beam Laser Ablation Of Dielectrics, Cheng Hsiang Lin, Zheng Hua Rao, Lan Jiang, Wu Jung Tsai, Ping Han Wu, Chih Wei Chien, Shean Jen Chen, Hai Lung Tsai Jul 2010

Investigations Of Femtosecond-Nanosecond Dual-Beam Laser Ablation Of Dielectrics, Cheng Hsiang Lin, Zheng Hua Rao, Lan Jiang, Wu Jung Tsai, Ping Han Wu, Chih Wei Chien, Shean Jen Chen, Hai Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

We have conducted experimental investigations for the micromachining of dielectrics (fused silica) using an integrated femtosecond (is) and nanosecond (ns) dual-beam laser system at different time delays between the fs and ns pulses. We found that the maximum ablation enhancement occurs when the fs pulse is shot near the peak of the ns pulse envelope. Enhancements up to 13.4 times in ablation depth and 50.7 times in the amount of material removal were obtained, as compared to fs laser ablation alone. the fs pulse increases the free electron density and changes the optical properties of fused silica to have metallic …

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Investigating Impact Of Quorum Construction On Data Processing In Mobile Ad Hoc Networks, Takahiro Hara, Sanjay K. Madria, Shojiro Nishio Jul 2010

Investigating Impact Of Quorum Construction On Data Processing In Mobile Ad Hoc Networks, Takahiro Hara, Sanjay K. Madria, Shojiro Nishio

Computer Science Faculty Research & Creative Works

In a mobile ad hoc network (MANET), since mobility of mobile hosts causes frequent network partitioning, consistency management of data operations on replicas becomes a crucial issue. in our previous work, we have defined several consistency levels for MANET applications and designed protocols to achieve these consistency levels. These protocols are mainly based on a dynamic quorum system to cope with network partitioning and node and network failures. in this paper, we further investigate the impact of quorum construction on the system performance through simulation studies. Specifically, we change the number of mobile hosts that replicate data items, and which …

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Crystallization Method For Benzphetamine, Dennis J. Kalota, Keith Tomazi Jul 2010

Crystallization Method For Benzphetamine, Dennis J. Kalota, Keith Tomazi

Chemical and Biochemical Engineering Faculty Research & Creative Works

There is disclosed a method for the crystallization of benzphetamine hydrochloride from an organic medium by the steps of removing water from the system to a very low level and then reducing the temperature of the organic medium to provide crystallization of the acid salt. In the event that crystallization does not occur upon lowering the temperature of the medium, it has been discovered that gentle heating of the organic medium results in crystallization of the acid salt. It has also been discovered that higher temperature crystallization has been provided by removal of methamphetamine from the composition. The crystalline benzphetamine …

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Asymmetrical Cascade Multilevel Converters With Noninteger Or Dynamically Changing Dc Voltage Ratios: Concepts And Modulation Techniques, Shuai Lu, Sébastien Mariéthoz, Keith Corzine Jul 2010

Asymmetrical Cascade Multilevel Converters With Noninteger Or Dynamically Changing Dc Voltage Ratios: Concepts And Modulation Techniques, Shuai Lu, Sébastien Mariéthoz, Keith Corzine

Electrical and Computer Engineering Faculty Research & Creative Works

Asymmetrical cascade multilevel inverters offer a high number of voltage levels with a given switch count. for a given topology, the number of levels depends on the configuration of the dc voltage (ratios). This paper deals with the design and control of such converters with Non integer dc voltage ratio, which leads to unevenly distributed space vectors. It describes how to select the dc voltage ratio configurations that yield space vectors as evenly distributed as possible. It describes how to produce an effective PWM modulation that allows generating undistorted current even in the presence of (some) unevenly distributed space vectors. …

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Reliability Modeling And Analysis Of Clockless Wave Pipeline Core For Embedded Combinational Logic Design, Tao Feng, Noh-Jin Park, Minsu Choi, Nohpill Park Jul 2010

Reliability Modeling And Analysis Of Clockless Wave Pipeline Core For Embedded Combinational Logic Design, Tao Feng, Noh-Jin Park, Minsu Choi, Nohpill Park

Electrical and Computer Engineering Faculty Research & Creative Works

This paper presents a model for analyzing the reliability of a clockless wave pipeline as an intellectual property (IP) core for embedded design. This design requires different clocking requirements by each embedded IP core during integration. Therefore, either partial or global lack of synchronization of the embedded clocking is considered for the data flow. The clockless wave pipeline represents an alternative to a traditional pipeline scheme; it requires an innovative computing model that is readily suitable for high-throughput computing by heterogeneous IP logic cores embedded in system-on-chip (SoC). A clockless wave pipeline technique relies on local asynchronous operation for seamless …

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Programmed For Success: Educating Tomorrow's Workforce, Mariesa Crow Jul 2010

Programmed For Success: Educating Tomorrow's Workforce, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

I recently stepped down as chair of the IEEE Power & Energy Society (PES) Power & Energy Education Committee (PEEC) to take my place among a very dedicated group of past chairs and exemplary educators. I have been an active member of the PEEC since the start of my academic career 20 years ago in 1990. The education committee is comprised of educators and practicing engineers who are committed to power engineering career development, university education, and lifelong learning. The committee strives to address issues of whole-life education. This issue of IEEE Power and Energy Magazine has six feature articles …

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The New Centurions, Lynn K. Stichnote, Mariesa Crow Jul 2010

The New Centurions, Lynn K. Stichnote, Mariesa Crow

Electrical and Computer Engineering Faculty Research & Creative Works

The current group of young people entering the workforce belong to the so-called "millennial generation." Each generation has certain characteristics that have defined its interaction with the world; the millennials have been called the "Net generation." They are the first generation that has never known life without the Internet. As a result of their protected, structured, and positively reinforced upbringing, the millennials are an exceptionally accomplished, positive, upbeat, and optimistic generation. The millennials are the quintessential multitaskers, and they are used to having the world at their fingertips through online search engines. If organizations use the best of the millennials' …

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Enforcing Information Flow Security Properties In Cyber-Physical Systems: A Generalized Framework Based On Compensation, Thoshitha T. Gamage, Bruce M. Mcmillin, Thomas P. Roth Jul 2010

Enforcing Information Flow Security Properties In Cyber-Physical Systems: A Generalized Framework Based On Compensation, Thoshitha T. Gamage, Bruce M. Mcmillin, Thomas P. Roth

Computer Science Faculty Research & Creative Works

This paper presents a general theory of event compensation as an information flow security enforcement mechanism for Cyber-Physical Systems (CPSs). The fundamental research problem being investigated is that externally observable events in modern CPSs have the propensity to divulge sensitive settings to adversaries, resulting in a confidentiality violation. This is a less studied yet emerging concern in modern system security. A viable method to mitigate such violations is to use information flow security based enforcement mechanisms since access control based security models cannot impose restrictions on information propagation. Further, the disjoint nature of security analysis is not appropriate for systems …

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The Effect Of Adding Organic Polymers On The Handling Properties, Strengths And Bioactivity Of A Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. W. Wren, N. M. Cummins, A. Coughlan, Mark R. Towler Jul 2010

The Effect Of Adding Organic Polymers On The Handling Properties, Strengths And Bioactivity Of A Ca-Sr-Zn-Si Glass Polyalkenoate Cement, A. W. Wren, N. M. Cummins, A. Coughlan, Mark R. Towler

Chemical and Biochemical Engineering Faculty Research & Creative Works

This work demonstrates the addition of a number of naturally occurring proteins/polymers to a zinc-based glass polyalkenoate cements (GPCs). Chitin (Chi.), collagen (Col.), cysteine (Cys.) and keratin (Ker.) were added with the intention of improving the bioactivity of this cement. Initial testing involved characterization of the glass with X-ray diffraction (XRD) and differential thermal analysis (DTA) before and after sterilization with γ-irradiation. No significant changes occurred as a result of sterilization. Handling properties of the modified cements were not significantly different from those of the control, BT 101 (Working Tw-36s, and setting time Ts-70 …

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Fivefold Differential Cross Sections For Ground-State Ionization Of Aligned H₂ By Electron Impact, Arne Senftleben, Ola A. Al-Hagan, Thomas Pfluger, Xueguang Ren, Don H. Madison, Alexander Dorn, Joachim Hermann Ullrich Jul 2010

Fivefold Differential Cross Sections For Ground-State Ionization Of Aligned H₂ By Electron Impact, Arne Senftleben, Ola A. Al-Hagan, Thomas Pfluger, Xueguang Ren, Don H. Madison, Alexander Dorn, Joachim Hermann Ullrich

Physics Faculty Research & Creative Works

We discuss the ionization of aligned hydrogen molecules into their ionic ground state by 200 eV electrons. Using a reaction microscope, the complete electron scattering kinematics is imaged over a large solid angle. Simultaneously, the molecular alignment is derived from postcollision dissociation of the residual ion. It is found that the ionization cross section is maximized for small angles between the internuclear axis and the momentum transfer. Fivefold differential cross sections (5DCSs) reveal subtle differences in the scattering process for the distinct alignments. We compare our observations with theoretical 5DCSs obtained with an adapted molecular three-body distorted wave model that …

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Astronomy's New Messengers: A Traveling Exhibit To Reach Out To A Young Adult Audience, Marco Cavaglia, Martin Hendry, Szabolocs Marka, David H. Reitze, Keith Riles Jul 2010

Astronomy's New Messengers: A Traveling Exhibit To Reach Out To A Young Adult Audience, Marco Cavaglia, Martin Hendry, Szabolocs Marka, David H. Reitze, Keith Riles

Physics Faculty Research & Creative Works

The Laser Interferometer Gravitational-wave Observatory exhibit Astronomy's New Messengers: Listening to the Universe with Gravitational Waves is traveling to colleges, universities, museums and other public institutions throughout the United States. In 2010, an extended version of this exhibit will appear in a New York City venue that is accessible to a large and diverse cross section of the general public. Astronomy's New Messengers primarily communicates with an adolescent and young adult audience, potentially inspiring them into the field of science. Acknowledging that this audience is traditionally a difficult one to attract, the exhibit publicly announces itself in a charismatic fashion …

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Scaled Vapor-To-Liquid Nucleation In A Lennard-Jones System, Barbara N. Hale, Mark Thomason Jul 2010

Scaled Vapor-To-Liquid Nucleation In A Lennard-Jones System, Barbara N. Hale, Mark Thomason

Physics Faculty Research & Creative Works

Scaling of the homogenous vapor-to-liquid nucleation rate, J, is observed in a model Lennard-Jones (LJ) system. The model uses Monte Carlo simulation-generated small cluster growth to decay rate constant ratios and the kinetic steady-state nucleation rate formalism to determine J at four temperatures below the LJ critical temperature, Tc. When plotted vs the scaled supersaturation, lnS/[Tc/T-1]3/2, the values of log J are found to collapse onto a single line. A similar scaling has been observed for the experimental nucleation rate data of water and toluene.

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Order-Dependent Mappings: Strong-Coupling Behavior From Weak-Coupling Expansions In Non-Hermitian Theories, Jean Zinn-Justin, Ulrich D. Jentschura Jul 2010

Order-Dependent Mappings: Strong-Coupling Behavior From Weak-Coupling Expansions In Non-Hermitian Theories, Jean Zinn-Justin, Ulrich D. Jentschura

Physics Faculty Research & Creative Works

A long time ago, it has been conjectured that a Hamiltonian with a potential of the form x 2+ivx 3, v real, has a real spectrum. This conjecture has been generalized to a class of the so-called PT symmetric Hamiltonians and some proofs have been given. Here, we show by numerical investigation that the divergent perturbation series can be summed efficiently by an order-dependent mapping (ODM) in the whole complex plane of the coupling parameter v 2, and that some information about the location of level-crossing singularities can be obtained in this way. Furthermore, we discuss to …

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Anderson Localization As Position-Dependent Diffusion In Disordered Waveguides, Ben Payne, Alexey Yamilov, Sergey E. Skipetrov Jul 2010

Anderson Localization As Position-Dependent Diffusion In Disordered Waveguides, Ben Payne, Alexey Yamilov, Sergey E. Skipetrov

Physics Faculty Research & Creative Works

We show that the recently developed self-consistent theory of Anderson localization with a position-dependent diffusion coefficient is in quantitative agreement with the supersymmetry approach up to terms of the order of 1/g 02 (with g0 the dimensionless conductance in the absence of interference effects) and with large-scale ab initio simulations of the classical wave transport in disordered waveguides, at least for g 0 ~ 0.5. In the latter case, agreement is found even in the presence of absorption. Our numerical results confirm that in open disordered media, the onset of Anderson localization can be viewed as position-dependent diffusion.

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Differential Cross Sections For Non-Sequential Double Ionization Of He By 52 Ev Photons From The Free Electron Laser In Hamburg, Flash, Moritz Kurka, Johannes Feist, Daniel A. Horner, Artem Rudenko, Yuhai Jiang, Kai Uwe Kuhnel, Lutz M. Foucar, Thomas N. Rescigno, Clyde William Mccurdy, Renate Pazourek, Stefan Nagele, Michael Schulz, Oliver Herrwerth, Matthias Lezius, Matthias F. Kling, Markus S. Schoffler, Ali Belkacem, Stefan Dusterer, Rolf Treusch, Barry I. Schneider, Lee A. Collins, Joachim Burgdorfer, Claus Dieter Schroter Jul 2010

Differential Cross Sections For Non-Sequential Double Ionization Of He By 52 Ev Photons From The Free Electron Laser In Hamburg, Flash, Moritz Kurka, Johannes Feist, Daniel A. Horner, Artem Rudenko, Yuhai Jiang, Kai Uwe Kuhnel, Lutz M. Foucar, Thomas N. Rescigno, Clyde William Mccurdy, Renate Pazourek, Stefan Nagele, Michael Schulz, Oliver Herrwerth, Matthias Lezius, Matthias F. Kling, Markus S. Schoffler, Ali Belkacem, Stefan Dusterer, Rolf Treusch, Barry I. Schneider, Lee A. Collins, Joachim Burgdorfer, Claus Dieter Schroter

Physics Faculty Research & Creative Works

Two-photon double ionization of He is studied at the Free Electron Laser in Hamburg (FLASH) by inspecting He2+ momentum (P-(He 2+)) distributions at 52 eV photon energy. We demonstrate that recoil ion momentum distributions can be used to infer information about highly correlated electron dynamics and find the first experimental evidence for 'virtual sequential ionization'. The experimental data are compared with the results of two calculations, both solving the time-dependent Schrodinger equation. We find good overall agreement between experiment and theory, with significant differences for cuts along the polarization direction that cannot be explained by the experimental resolution …

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Effects Of Hydrogen Bonding On Vibrational Normal Modes Of Pyrimidine, Austin A. Howard, Gregory S. Tschumper, Nathan I. Hammer Jul 2010

Effects Of Hydrogen Bonding On Vibrational Normal Modes Of Pyrimidine, Austin A. Howard, Gregory S. Tschumper, Nathan I. Hammer

Chemistry Faculty Research & Creative Works

The effects of weak intermolecular interactions on 10 vibrational normal modes of pyrimidine are investigated by Raman spectroscopy and electronic structure computations. Hydrogen-bonded networks of water induce a shift to higher energy in certain normal modes of pyrimidine with increasing water concentration, while other modes are relatively unaffected. Pyrimidine molecules also exhibit weak C-H⋯N interactions and shifted normal modes upon crystallization. The selective nature of the shifting of normal modes to higher energy allows for definitive assignments of the nearly degenerate ν8a and ν8b modes with polarized Raman spectroscopy. Natural bond orbital (NBO) analyses indicate that when water molecules donate …

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Viscosity Effects In Vibratory Mobilization Of Residual Oil, Igor A. Beresnev, Wen Deng Jul 2010

Viscosity Effects In Vibratory Mobilization Of Residual Oil, Igor A. Beresnev, Wen Deng

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The last decade has seen clarifications of the underlying capillary physics behind stimulation of oil production by seismic waves and vibrations. Computational studies have prevailed, however, and no viscous hydrodynamic theory of the phenomenon has been proposed. For a body of oil entrapped in a pore channel, viscosity effects are naturally incorporated through a model of two-phase core-annular flow. These effects are significant at the postmobilization stage, when the resistance of capillary forces is overcome and viscosity becomes the only force resisting an oil ganglion's motion. A viscous equation of motion follows, and computational fluid dynamics (CFD) establishes the limits …

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Uncertainty Quantification Integrated To The Cfd Modeling Of Synthetic Jet Actuators, Srikanth Adya, Daoru Frank Han, Serhat Hosder Jul 2010

Uncertainty Quantification Integrated To The Cfd Modeling Of Synthetic Jet Actuators, Srikanth Adya, Daoru Frank Han, Serhat Hosder

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The Point Collocation Non-Intrusive Polynomial Chaos (NIPC) method has been applied to two stochastic synthetic jet actuator problems used as test cases in the CFDVAL2004 workshop to demonstrate the integration of computationally efficient uncertainty quantification to the high-fidelity CFD modeling of synthetic jet actuators. In Case1 where the synthetic jet is issued into quiescent air, the NIPC method is used to quantify the uncertainty in the long-time averaged u and v-velocities at several locations in the flow field, due to the uniformly distributed uncertainty introduced in the amplitude and frequency of the oscillation of the piezo-electric membrane. Fifth order NIPC …

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Microwave And Millimeter Wave Imaging System, R. Zoughi, Mohamed Ahmed Aboukhousa, Mohammad Tayeb Ahmad Ghasr, Sergey Kharkovsky, David Pommerenke Jun 2010

Microwave And Millimeter Wave Imaging System, R. Zoughi, Mohamed Ahmed Aboukhousa, Mohammad Tayeb Ahmad Ghasr, Sergey Kharkovsky, David Pommerenke

Electrical and Computer Engineering Faculty Research & Creative Works

A sensor array having a plurality of modulated slots for microwave and/or millimeter wave imaging. The locations of the slots in the array define a spatial domain away from an object for detecting an electric field from the object. Each of the slots outputs a signal representative of the measured field and the location of the slot. A processor decodes the signals and generates an image of the object.

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Prediction Of The Transport Properties Of A Polyatomic Gas, Zhi Liang, Hai-Lung Tsai Jun 2010

Prediction Of The Transport Properties Of A Polyatomic Gas, Zhi Liang, Hai-Lung Tsai

Mechanical and Aerospace Engineering Faculty Research & Creative Works

An Ab Initio Molecular Potential Model is Employed in This Paper to Show its Excellent Predictability for the Transport Properties of a Polyatomic Gas from Molecular Dynamics Simulations. a Quantum Mechanical Treatment of Molecular Vibrational Energies is Included in the Green and Kubo Integral Formulas for the Calculation of the Thermal Conductivity by the Metropolis Monte Carlo Method. using CO2 Gas as an Example, the Fluid Transport Properties in the Temperature Range of 300-1000 K Are Calculated Without using Any Experimental Data. the Accuracy of the Calculated Transport Properties is Significantly Improved by the Present Model, Especially for the Thermal …

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Validating Module Heuristics On Large Scale Products, Rachel Day, Robert B. Stone, Katie Grantham Lough Jun 2010

Validating Module Heuristics On Large Scale Products, Rachel Day, Robert B. Stone, Katie Grantham Lough

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Decreasing time and costs is a major objective in many businesses today. Including modularity in the early design phases can effectively decrease time spent on and costs associated with a project. the task of identifying modules within a product early in the design process (when decisions are less expensive) is made less daunting by using the techniques of functional modeling and module heuristics. This paper discusses the results of the initial efforts to verify the module heuristics on large products (products with functional models consisting of more than 30 sub-functions) since the module heuristics were originally developed on small products. …

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