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Comment On "Giant Plasticity Of A Quantum Crystal", Caizhi Zhou, Charles J. Olson Reichhardt, Matthias J. Graf, Jungjung Su, Alexander V. Balatsky, Irene J. Beyerlein Sep 2013

Comment On "Giant Plasticity Of A Quantum Crystal", Caizhi Zhou, Charles J. Olson Reichhardt, Matthias J. Graf, Jungjung Su, Alexander V. Balatsky, Irene J. Beyerlein

Materials Science and Engineering Faculty Research & Creative Works

In their Letter, Haziot et al. report a novel phenomenon of giant plasticity for hcp 4He quantum crystals. They assert that 4He exhibits mechanical properties not found in classical plasticity theory. Specifically, they examine high-quality crystals as a function of temperature T and applied strain ϵapp, where the shear modulus µ =Tapp/ϵapp reaches a plateau and dissipation 1=Q becomes close to zero; both quantities are reported to be independent of applied stress Tapp and strain ϵapp, implying a reversible dissipation process and suggesting dislocation motion by quantum tunneling. At lower …

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Atomic Layer Deposited Highly Dispersed Platinum Nanoparticles Supported On Non-Functionalized Multiwalled Carbon Nanotubes For The Hydrogenation Of Xylose To Xylitol, Xinhua Liang, Chengjun Jiang Sep 2013

Atomic Layer Deposited Highly Dispersed Platinum Nanoparticles Supported On Non-Functionalized Multiwalled Carbon Nanotubes For The Hydrogenation Of Xylose To Xylitol, Xinhua Liang, Chengjun Jiang

Chemical and Biochemical Engineering Faculty Research & Creative Works

Highly dispersed platinum nanoparticles were deposited on gram quantities of non-functionalized multiwalled carbon nanotubes (MWCNTs) by atomic layer deposition (ALD) in a fluidized bed reactor at 300°C. (Methylcyclopentadienyl) trimethylplatinum and oxygen were used as precursors. The results of TEM analysis showed that ∼1.3 nm Pt nanoparticles were highly dispersed on non-functionalized MWCNTs. The porous structures of MWCNTs did not change with the deposition of Pt nanoparticles. For comparison, the commercial 3 wt.% Pt/C catalyst was also characterized. The ALD-prepared Pt/MWCNT was used for the hydrogenation of xylose to xylitol. The ALD-prepared Pt/MWCNT showed the best catalytic performance with 100 % …

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Self-Potential Signals Generated By The Corrosion Of Buried Metallic Objects With Application To Contaminant Plumes, Justin B. R. Rittgers, Andre Revil, Marios C. Karaoulis, Michael A. Mooney, Lee D. Slater, Estella A. Atekwana Sep 2013

Self-Potential Signals Generated By The Corrosion Of Buried Metallic Objects With Application To Contaminant Plumes, Justin B. R. Rittgers, Andre Revil, Marios C. Karaoulis, Michael A. Mooney, Lee D. Slater, Estella A. Atekwana

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

Large-amplitude (>100 mV) negative electric (self)-potential anomalies are often observed in the vicinity of buried metallic objects and ore bodies or over groundwater plumes associated with organic contaminants. To explain the physical and chemical mechanisms that generate such electrical signals, a controlled laboratory experiment was carried out involving two metallic cylinders buried with vertical and horizontal orientations and centered through and in the capillary fringe within a sandbox. The 2D and 3D self-potential (SP) data were collected at several time steps along with collocated pH and redox potential measurements. Large dipolar SP and redox potential anomalies developed in association …

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Comparison Of Prestress Losses For Pedestrian Bridges Constructed With High-Strength Concrete And High-Strength Self-Consolidating Concrete, John J. Myers, Kurt E. Bloch Sep 2013

Comparison Of Prestress Losses For Pedestrian Bridges Constructed With High-Strength Concrete And High-Strength Self-Consolidating Concrete, John J. Myers, Kurt E. Bloch

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Abstract Two precast prestressed high-strength concrete and high-strength self-consolidating concrete pedestrian bridges were designed and erected in Rolla, Missouri, for an in situ investigative study to monitor time-dependent losses. Using the temperature and strain data monitored by the vibrating wire strain gauges within the beam cross sections, time-dependent losses were determined and compared between the bridges and various empirical expressions presented by AASHTO and the Precast/Prestressed Concrete Institute. © 2013 American Society of Civil Engineers.

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Distribution And Accumulation Of Trichloroethylene And Trichloroacetic Acid In Hybrid Poplars, Lucas Odom, Joel Gerard Burken, Lee Newman Sep 2013

Distribution And Accumulation Of Trichloroethylene And Trichloroacetic Acid In Hybrid Poplars, Lucas Odom, Joel Gerard Burken, Lee Newman

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Hybrid Poplar Trees Are Known to Take Up Trichloroethylene (TCE) into above Ground Tissues, Where It Degrades into the Metabolites Trichloroacetic Acid (TCAA), Dichloroacetic Acid, and Trichloroethanol and Where Parent Chlorinated Solvents Volatilize to the Atmosphere. based on This Knowledge, Numerous Phytoremediation Applications Have Been Implemented for TCE and Other Chlorinated Solvents. Sampling of Plant Tissues Has Proven Effective for Phytoforensic and Phytoscreening Applications in Assessing Sites and Evaluating the Efficacy of Phytoremediation. However, Little is Known About the Appropriate Exposure Times and Sampling Locations Required to Obtain an Accurate Assessment of TCE and Metabolites. in This Study, Hybrid Poplars …

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Automated Methods To Determine Electrospun Fiber Alignment And Diameter Using The Radon Transform, Nicholas J. Schaub, Sean J. Kirkpatrick, Ryan J. Gilbert Sep 2013

Automated Methods To Determine Electrospun Fiber Alignment And Diameter Using The Radon Transform, Nicholas J. Schaub, Sean J. Kirkpatrick, Ryan J. Gilbert

Chemical and Biochemical Engineering Faculty Research & Creative Works

Recent evidence demonstrates the ability to change cell function by altering the physical properties of electro spun scaffolds, but many studies still do not characterize electro spun fiber alignment and diameter. To aid in the reporting of these crucial properties, we demonstrate two methods of quantifying electro spun fiber alignment with one method capable of determining electro spun fiber diameter. The first method assesses fiber alignment in a scanning electron microscopy image using the Radon Transform (RT) to calculate the entropy of the fibers in the image. The RT entropy method was more sensitive than a commonly used Fast Fourier …

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Computational Modeling And Experimental Study On Optical Microresonators Using Optimal Spherical Structure For Chemical Sensing, Hanzheng Wang, Lei Yuan, Jie Huang, Xinwei Lan, Cheol-Woon Kim, Lan Jiang, Hai Xiao Sep 2013

Computational Modeling And Experimental Study On Optical Microresonators Using Optimal Spherical Structure For Chemical Sensing, Hanzheng Wang, Lei Yuan, Jie Huang, Xinwei Lan, Cheol-Woon Kim, Lan Jiang, Hai Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

Chemical sensors based on optical microresonators have been demonstrated highly sensitive by monitoring the refractive index (RI) changes in the surrounding area near the resonator surface. In an optical resonator, the Whispering Gallery Modes (WGMs) with high quality (Q) factor supported by the spherical symmetric structure interacts with the contiguous background through evanescent field. Highly sensitive detection can be realized because of the long lifetime of the photons. The computational models of solid glass microspheres and hollow glass spheres with porous wall (PW-HGM) were established. These two types of microresonators were studied through simulations. The PWHGM resonator was proved as …

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Slab Flattening Trigger For Isotopic Disturbance And Magmatic Flareup In The Southernmost Sierra Nevada Batholith, California, Alan D. Chapman, Jason B. Saleeby, John Eiler Sep 2013

Slab Flattening Trigger For Isotopic Disturbance And Magmatic Flareup In The Southernmost Sierra Nevada Batholith, California, Alan D. Chapman, Jason B. Saleeby, John Eiler

Geosciences and Geological and Petroleum Engineering Faculty Research & Creative Works

The San Emigdio Schist of Southern California permits examination of partial melting and devolatilization processes along a Late Cretaceous shallow subduction zone. Detrital and recrystallized zircon of the structurally highest portions of the schist bracket the depositional age to between ca. 102 and 98 Ma. Zircon oxygen isotope data from both lower-plate schist and upper-plate assemblages of the Sierra Nevada batholith (SNB) reveal a δ18O shift of ̃1.5% between igneous (̃5.5%) and recrystallized (̃7%) domains. These results, taken with previous zircon and whole-rock δ18O measurements, provide evidence for devolatilization and/or partial melting of the schist and fluid ascent through overlying …

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Pre-Distribution Scheme For Data Sharing In Mobile Cloud Computing, Chaitanya Vemulapalli, Sanjay Kumar Madria, Mark Linderman Aug 2013

Pre-Distribution Scheme For Data Sharing In Mobile Cloud Computing, Chaitanya Vemulapalli, Sanjay Kumar Madria, Mark Linderman

Computer Science Faculty Research & Creative Works

computing gave rise to a new computing paradigm called Mobile Cloud Computing (MCC) that gives the flexibility to access information and computing resources anywhere anytime. In many applications, mobile nodes capture images/video clips and exchange with other mobile peers (on demand) and use local access points for efficient smooth distribution of information in the wireless network. In such a situation, a three-way data management and dissemination technique is helpful because it provides both data management and distribution at different levels of granularity. The main motivation of this paper is that we seek a balance between accessing information from a remote …

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The Missouri Miner, August 29, 2013 Aug 2013

The Missouri Miner, August 29, 2013

The Missouri Miner Newspaper

No abstract provided.

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Numerical Simulation Of Vortex-Induced Vibration Of Two Circular Cylinders Of Different Diameters At Low Reynolds Number, Ming Zhao, Guirong Yan Aug 2013

Numerical Simulation Of Vortex-Induced Vibration Of Two Circular Cylinders Of Different Diameters At Low Reynolds Number, Ming Zhao, Guirong Yan

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Two-Degree-Of-Freedom Vortex-Induced Vibration (VIV) of Two Rigidly Coupled Circular Cylinders of Different Diameters at a Low Reynolds Number of 250 is Investigated Numerically. While the Diameter Ratio and the Mass Ratio Are Kept Constant, the Study is Focused on the Effect of the Position Angle of the Small Cylinder on the Lock-In Regime of the VIV. Simulations Are Carried Out for Position Angles Α of the Small Cylinder Ranging from 0° to 180° with an Interval of 22.5° and the Reduced Velocities Ranging from 1 to 15 with an Increment of 1. in Order to Find the Effect of the …

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High Memory Passive Rfid Tags With Multimodal Sensor Design And Application To Asset Monitoring In-Transit, Haifeng Niu, S. Jagannathan Aug 2013

High Memory Passive Rfid Tags With Multimodal Sensor Design And Application To Asset Monitoring In-Transit, Haifeng Niu, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, new passive Radio Frequency Identification (RFID) tags with multimodal sensors and a high on-tag memory is proposed. First, the features preferred on the new passive RFID tags are motivated followed by a detailed description on the design and fabrication of the tags. Next, the performance of the tags in terms of read range is evaluated. The experiments results show that proposed tags have a range of 5.8 meters when all sensors are disabled while the range reduces when sensors are enabled. However, it is demonstrated that the range can be enhanced to 8 meters by using energy …

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Oscillons And Oscillating Kinks In The Abelian-Higgs Model, V. Achilleos, F. K. Diakonos, D. J. Frantzeskakis, Garyfallia C. Katsimiga, X. N. Maintas, E. Manousakis, C. E. Tsagkarakis, A. Tsapalis Aug 2013

Oscillons And Oscillating Kinks In The Abelian-Higgs Model, V. Achilleos, F. K. Diakonos, D. J. Frantzeskakis, Garyfallia C. Katsimiga, X. N. Maintas, E. Manousakis, C. E. Tsagkarakis, A. Tsapalis

Physics Faculty Research & Creative Works

We study the classical dynamics of the Abelian Higgs model employing an asymptotic multiscale expansion method, which uses the ratio of the Higgs to the gauge field amplitudes as a small parameter. We derive an effective nonlinear Schrödinger equation for the gauge field, and a linear equation for the scalar field containing the gauge field as a nonlinear source. This equation is used to predict the existence of oscillons and oscillating kinks for certain regimes of the ratio of the Higgs to the gauge field masses. Results of direct numerical simulations are found to be in very good agreement with …

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Directional Phytoscreening: Contaminant Gradients In Trees For Plume Delineation, Matt A. Limmer, Mikhil K. Shetty, Samantha Markus, Ryan Kroeker, Beth L. Parker, Camilo Martinez, Joel Gerard Burken Aug 2013

Directional Phytoscreening: Contaminant Gradients In Trees For Plume Delineation, Matt A. Limmer, Mikhil K. Shetty, Samantha Markus, Ryan Kroeker, Beth L. Parker, Camilo Martinez, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Tree Sampling Methods Have Been Used in Phytoscreening Applications to Delineate Contaminated Soil and Groundwater, Augmenting Traditional Investigative Methods that Are Time-Consuming, Resource-Intensive, Invasive, and Costly. in the Past Decade, Contaminant Concentrations in Tree Tissues Have Been Shown to Reflect the Extent and Intensity of Subsurface Contamination. This Paper Investigates a New Phytoscreening Tool: Directional Tree Coring, a Concept Originating from Field Data that Indicated Azimuthal Concentrations in Tree Trunks Reflected the Concentration Gradients in the Groundwater Around the Tree.To Experimentally Test This Hypothesis, Large Diameter Trees Were Subjected to Subsurface Contaminant Concentration Gradients in a Greenhouse Study. These Trees …

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Fast And Accurate Multiscale Electromagnetic Modeling Framework: An Overview, W. C. Chew, A. C. Cangellaris, J. Schutt-Aine, H. Braunisch, Z. G. Qian, A. A. Aydiner, K. Aygun, L. (Lijun) J. Jiang, Z. H. Ma, L. L. Meng, M. Naeem Aug 2013

Fast And Accurate Multiscale Electromagnetic Modeling Framework: An Overview, W. C. Chew, A. C. Cangellaris, J. Schutt-Aine, H. Braunisch, Z. G. Qian, A. A. Aydiner, K. Aygun, L. (Lijun) J. Jiang, Z. H. Ma, L. L. Meng, M. Naeem

Electrical and Computer Engineering Faculty Research & Creative Works

We present an overview of challenge problems in electromagnetic modeling of highly complex and multi-scale structures found in 3D IC, SiP, SoC, and electronic packaging necessary for signal integrity assessment. © 2013 IEEE.

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Compressed Sensing For Sar-Based Wideband Three-Dimensional Microwave Imaging System Using Non-Uniform Fast Fourier Transform, Hamed Kajbaf, Joseph T. Case, Zengli Yang, Yahong Rosa Zheng Aug 2013

Compressed Sensing For Sar-Based Wideband Three-Dimensional Microwave Imaging System Using Non-Uniform Fast Fourier Transform, Hamed Kajbaf, Joseph T. Case, Zengli Yang, Yahong Rosa Zheng

Electrical and Computer Engineering Faculty Research & Creative Works

A new compressed sensing (CS) image reconstruction method is proposed for high-resolution wideband three-dimensional synthetic aperture radar (SAR) imaging systems. In contrast to existing CS SAR methods that employ only a forward SAR transform in pre- or post-processing, the proposed method employs both forward SAR and reverse SAR (R-SAR) transforms in each CS iteration to improve the quality of reconstructed images. This study proposes a simple and elegant truncation repair method to combat the truncation error and utilizes non-uniform fast Fourier transform to reduce the SAR and R-SAR transform errors, thereby ensuring the convergence of the CS algorithm and improving …

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Noncontact Operation-State Monitoring Technology Based On Magnetic-Field Sensing For Overhead High-Voltage Transmission Lines, Xu Sun, Qi Huang, Yunhe Hou, Lijun Jiang, Philip W.T. Pong Aug 2013

Noncontact Operation-State Monitoring Technology Based On Magnetic-Field Sensing For Overhead High-Voltage Transmission Lines, Xu Sun, Qi Huang, Yunhe Hou, Lijun Jiang, Philip W.T. Pong

Electrical and Computer Engineering Faculty Research & Creative Works

This paper proposed a novel noncontact technology of operation-state monitoring based on magnetic-field sensing for high-voltage transmission lines, which can simultaneously measure both electrical and spatial parameters in real time. This technology was derived from research on the magnetic-field distribution at the ground level when the transmission lines operate in different states, including sagging, galloping, and current imbalance. Two typical models of high-voltage three-phase transmission lines were simulated, and the resulting magnetic fields were calculated. The correlation between the magnetic-field variations and the operation states were analyzed. Based on such correlation, a source reconstruction method was developed to reconstruct the …

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Practical Linear Precoder Design For Finite Alphabet Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing With Experiment Validation, Yahong Rosa Zheng, Mingxi Wang, Weiliang Zeng, Chengshan Xiao Aug 2013

Practical Linear Precoder Design For Finite Alphabet Multiple-Input Multiple-Output Orthogonal Frequency Division Multiplexing With Experiment Validation, Yahong Rosa Zheng, Mingxi Wang, Weiliang Zeng, Chengshan Xiao

Electrical and Computer Engineering Faculty Research & Creative Works

A low complexity precoding method is proposed for practical multiple-input multiple-output (MIMO) orthogonal frequency-division multiplexing (OFDM) systems. Based on the two-step optimal precoder design algorithm that maximizes the lower bound of the mutual information with finite-alphabet inputs, the proposed method simplifies the precoder design by fixing the right singular vectors of the precoder matrix, eliminating the iterative optimization between the two steps, and discretizing the search space of the power allocation vector. For a 4 x 4 channel, the computational complexity of the proposed precoder design is reduced to 3 and 6% of that required by the original two-step algorithm …

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On The Futility Of Thermal Through-Silicon-Vias, Chung Han Chou, Nien Yu Tsai, Hao Yu, Yiyu Shi, Jui Hung Chien Aug 2013

On The Futility Of Thermal Through-Silicon-Vias, Chung Han Chou, Nien Yu Tsai, Hao Yu, Yiyu Shi, Jui Hung Chien

Electrical and Computer Engineering Faculty Research & Creative Works

Thermal integrity is one of the most important challenges faced by three-dimensional integrated circuits (3D ICs). Towards this, thermal through-silicon-vias (TTSVs) have been widely used to assist heat dissipation. The metal inside TTSVs can conduct heat more effectively than the silicon substrate, and the metal bumps underneath TTSVs can help heat penetrate through the inter-layer thermal interface material (TIM). However, the surrounding silicon dioxide blocks the heat flowing into them. This makes the effectiveness of TTSVs questionable. In this paper, we argue that some existing TTSV models fail to capture those effects. Experimental results based on finite element simulations verify …

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Probabilistic Simulation Of Solidification Microstructure Evolution During Laser-Based Metal Deposition, Jingwei Zhang, Frank W. Liou, William Seufzer, Joseph William Newkirk, Zhiqiang Fan, Heng Liu, Todd E. Sparks Aug 2013

Probabilistic Simulation Of Solidification Microstructure Evolution During Laser-Based Metal Deposition, Jingwei Zhang, Frank W. Liou, William Seufzer, Joseph William Newkirk, Zhiqiang Fan, Heng Liu, Todd E. Sparks

Mechanical and Aerospace Engineering Faculty Research & Creative Works

A predictive model, based on a Cellular Automaton (CA) - Finite Element (FE) method, has been developed to simulate microstructure evolution during metal solidification for a laser based additive manufacturing process. The macroscopic FE calculation was designed to update the temperature field and simulate a high cooling rate. In the microscopic CA model, heterogeneous nucleation sites, preferential growth orientation and dendritic grain growth kinetics were simulated. The CA model was able to show the entrapment of neighboring cells and the relationship between undercooling and the grain growth rate. The model predicted the dendritic grain size, structure, and morphological evolution during …

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Effect Of Architecture And Porosity On Mechanical Properties Of Borate Glass Scaffolds Made By Selective Laser Sintering, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Taylor Comte Aug 2013

Effect Of Architecture And Porosity On Mechanical Properties Of Borate Glass Scaffolds Made By Selective Laser Sintering, Krishna C. R. Kolan, Ming-Chuan Leu, Greg Hilmas, Taylor Comte

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The porosity and architecture of bone scaffolds, intended for use in bone repair or replacement, are two of the most important parameters in the field of bone tissue engineering. The two parameters not only affect the mechanical properties of the scaffolds but also aid in determining the amount of bone regeneration after implantation. Scaffolds with five different architectures and four porosity levels were fabricated using borate bioactive glass (13-93B3) using the selective laser sintering (SLS) process. The pore size of the scaffolds varied from 400 to 1300 μm. The compressive strength of the scaffolds varied from 1.7 to 15.5 MPa …

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Development Of Freeze-Form Extrusion Fabrication With Use Of Sacrificial Material, Ming-Chuan Leu, Diego A. Garcia Aug 2013

Development Of Freeze-Form Extrusion Fabrication With Use Of Sacrificial Material, Ming-Chuan Leu, Diego A. Garcia

Mechanical and Aerospace Engineering Faculty Research & Creative Works

The development of Freeze-form Extrusion Fabrication (FEF) process to fabricate three-dimensional (3D) ceramic parts with use of sacrificial material to build support sections during the fabrication process is presented in this paper. FEF is an environmentally friendly, additive manufacturing process that builds 3D parts in a freezing environment layer-by-layer by computer controlled extrusion and deposition of aqueous colloidal pastes based on computer-aided design (CAD) models. Methyl cellulose was identified as the support material, and alumina was used as the main material in this study. After characterizing the dynamics of extruding alumina and methyl cellulose pastes, a general tracking controller was …

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Additive Manufacturing Laser Deposition Of Ti‐6al‐4v For Aerospace Repair Applications, Nanda Kumar Dey, Frank W. Liou, C. Nedic Aug 2013

Additive Manufacturing Laser Deposition Of Ti‐6al‐4v For Aerospace Repair Applications, Nanda Kumar Dey, Frank W. Liou, C. Nedic

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Parts or products from high performance metal are very expensive, partly due to the processing complexities during manufacturing. The purpose of this project is to use additive laser deposition and machining processes to repair titanium parts, thus extending the service life of these parts. The study broadly included preparing the defects, laser deposition, machining, sample preparation and mechanical tests. Comparative study of mechanical properties (UTS, YS, percentage elongation) of the repaired samples to the ideal conditions was undertaken. The research throws up interesting facts where the data from the test sample shows enhancement of properties of the repaired part.

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Experimental Investigation Of Different Cellular Lattice Structures Manufactured By Fused Deposition Modeling, Osman Iyibilgin, Cemil Yigit, Ming-Chuan Leu Aug 2013

Experimental Investigation Of Different Cellular Lattice Structures Manufactured By Fused Deposition Modeling, Osman Iyibilgin, Cemil Yigit, Ming-Chuan Leu

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Experimental tests were conducted to evaluate the compressive properties (yield strength and compressive modulus) and build time for five different cellular lattice structures fabricated by the Fused Deposition Modeling (FDM) process. The lattice structures had repeating unit cells, and the shapes of the unit cell under study included honeycomb, square, diamond, triangle, and circle. Test specimens were manufactured by a Stratasys Fortus 400mc machine using ABS (Acrylonitrile Butadiene Styrene) as the part material. The five different lattice structures were compared with each other and also with the sparse and sparse-double dense build styles that are directly available from the Fortus …

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Vision-Based Process Monitoring For Laser Metal Deposition Processes, Sreekar Karnati, Niroop Matta, Todd E. Sparks, Frank W. Liou Aug 2013

Vision-Based Process Monitoring For Laser Metal Deposition Processes, Sreekar Karnati, Niroop Matta, Todd E. Sparks, Frank W. Liou

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Laser Metal deposition is a process with immense scope and promise for becoming a robust manufacturing technology in the near future. Monitoring process variables is very instrumental in process planning and output monitoring. The current work deals with realizing the effect of power modulation on size of the high temperature region during deposition with varying powder feed. A thermal camera was used to visualize and analyze the deposition process. The area of the high temperature region through the deposition was identified and compared to realize the effect of each variable parameter during deposition. The power modulation was fruitful in modulating …

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Dynamic Properties Of Fine-Grained Soils Engineered With A Controlled Organic Phase, B. Bate, H. Choo, S. E. Burns Aug 2013

Dynamic Properties Of Fine-Grained Soils Engineered With A Controlled Organic Phase, B. Bate, H. Choo, S. E. Burns

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

Soils with high organic content are frequently encountered beneath earthquake sensitive infrastructure, such as bridges or levees. Historically, the dynamic properties of these organically rich soils have been difficult to predict due to the heterogeneity of the natural organic matter that is found in natural soils, even though their response to dynamic loading remains critical to assessing the ongoing stability of the infrastructure. In this study, an experimental investigation was performed on a montmorillonite soil that was modified with a controlled organic phase. Quaternary ammonium cations were exchanged onto the soil particle surfaces through cation exchange with the clay's naturally …

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Numerical Analysis Of Thermal Stress And Deformation In Multi-Layer Laser Metal Deposition Processes, Heng Liu, Todd E. Sparks, Frank W. Liou, David M. Dietrich Aug 2013

Numerical Analysis Of Thermal Stress And Deformation In Multi-Layer Laser Metal Deposition Processes, Heng Liu, Todd E. Sparks, Frank W. Liou, David M. Dietrich

Mechanical and Aerospace Engineering Faculty Research & Creative Works

Direct metal deposition (DMD) has gained increasing attention in the area of rapid manucooling rate, resulting in residual stresses and distortion. This paper presents a 3D sequentially coupled thermo-mechanical finite element model to predict residual stresses and deformations. The temperature distribution, thermal stress field and geometry deformation across domain are illustrated. The effect of deposition parameters on residual stress and deflections are also explored. A set of validation experiments for mechanical effects were conducted using laser displacement sensor. The comparisons between the simulated and experimental results show good agreement

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Optimized Waveform Relaxation Solution Of Rlcg Transmission Line Type Circuits, Mohammad D. Al-Khaleel, Martin J. Gander, Albert E. Ruehli Aug 2013

Optimized Waveform Relaxation Solution Of Rlcg Transmission Line Type Circuits, Mohammad D. Al-Khaleel, Martin J. Gander, Albert E. Ruehli

Electrical and Computer Engineering Faculty Research & Creative Works

Today, parallel processing is necessary for the solution of large systems of ordinary differential equations (ODEs) as they are obtained from large electronic circuits or from discretizing partial differential equations (PDEs). Using a fine mesh in the discretization of these problems also leads to large compute times and large storage requirements. The waveform relaxation (WR) technique, which is ideally suited for the use of multiple processors for problems with multiple time scales has been used to solve such problems on parallel processors for such large systems of ODEs. However, applying the so-called classical WR techniques to strongly coupled systems leads …

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Partial And Internal Inductance: Two Of Clayton R. Paul's Many Passions, Christopher L. Holloway, Edward F. Kuester, Albert E. Ruehli, Giulio Antonini Aug 2013

Partial And Internal Inductance: Two Of Clayton R. Paul's Many Passions, Christopher L. Holloway, Edward F. Kuester, Albert E. Ruehli, Giulio Antonini

Electrical and Computer Engineering Faculty Research & Creative Works

Inductance is one of the fundamental defined parameters in electromagnetics and it takes on a variety of formulations and definitions in the electromagnetic compatibility (EMC) community. The concept of inductance in its many definitions, uses, and caveats was central among Dr. Clayton R. Paul's contributions to the EMC community. In this paper, we discuss the various aspects of inductance which Dr. Paul helped to pioneer. In particular, the concepts of partial inductance and internal inductance (including skin effect) were two of his passions. This paper will both serve as a summary of Dr. Paul's work on inductance as well as …

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Etis - Efficient Trust And Identity Management System For Federated Service Providers, Makarand V. Bhonsle, Nayot Poolsappasit, Sanjay K. Madria Aug 2013

Etis - Efficient Trust And Identity Management System For Federated Service Providers, Makarand V. Bhonsle, Nayot Poolsappasit, Sanjay K. Madria

Computer Science Faculty Research & Creative Works

With the expectation of ever-increasing network of service providers due to Cloud and Web services explosion, security of user information is a major concern when it comes to the implementation of these services. This paper addresses the issue of identity management in a typical service providers' environment without the need for a trusted third party to federate the user identity for acquainted service providers. We leverage the establishment of trust between cross-domain service providers (SPs) to themselves rather than relying on a third party that brokers the trust between service providers. The hence formed network of SPs is then ready …

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