Digital Commons Network^™

Comment On "Singly Ionizing 100-Mev/Amu C⁶⁺+He Collisions With Small Momentum Transfer", Michael Schulz, Robert Moshammer, Daniel Fischer, Joachim Hermann Ullrich

Physics Faculty Research & Creative Works

In a recent article, Kouzakov suggested that experimental resolution effects can be responsible for discrepancies between measured and calculated fully differential cross sections for the ionization of helium by fast C⁶⁺ impact. They further asserted that projectile-coherence effects have no influence on the measured cross sections. In this Comment, we reiterate that the experimental resolution can only explain part of the discrepancies. Furthermore, we note that the conclusion regarding the role of projectile coherence neglects potential interference between first- and higher-order transition amplitudes.

Phonon Lifetime Investigation Of Anharmonicity And Thermal Conductivity Of Uo₂ By Neutron Scattering And Theory, Judy W. Pang, William J. Buyers, Aleksandr V. Chernatynskiy, Mark D. Lumsden, Bennett C. Larson, Simon R. Phillpot

Physics Faculty Research & Creative Works

Inelastic neutron scattering measurements of individual phonon lifetimes and dispersion at 295 and 1200 K have been used to probe anharmonicity and thermal conductivity in UO₂. They show that longitudinal optic phonon modes carry the largest amount of heat, in contrast to past simulations and that the total conductivity demonstrates a quantitative correspondence between microscopic and macroscopic phonon physics. We have further performed first-principles simulations for UO₂ showing semiquantitative agreement with phonon lifetimes at 295 K, but larger anharmonicity than measured at 1200 K.

Superplasticity And Microstructural Stability In A Mg Alloy Processed By Hot Rolling And Friction Stir Processing, V. Jain, R. S. Mishra, R. Verma, E. Essadiqi

Materials Science and Engineering Faculty Research & Creative Works

The superplastic behavior of a Mg-1.2 Zn-1.7 Y-0.53 Al-0.27 Mn alloy sheet processed by hot rolling and friction stir processing (FSP) was investigated. The kinetics of superplastic deformation were compared with Mg-3 Al-1 Zn and other Mg-Zn-Y alloys processed by different methods. The FSP Mg-1.2 Zn-1.7 Y-0.53 Al-0.27 Mn alloy exhibits slower kinetics of deformation compared with other alloys. The microstructural stability of the FSP Mg-1.2 Zn-1.7 Y-0.53 Al-0.27 Mn alloy is better than the Mg-3 Al-1 Zn alloy because of the presence of different types of precipitates. © 2012 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Special Section On Natural Treatment Systems: More Than Just A Solution To Pollution, Joel Gerard Burken

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

No abstract provided.

Neural Network-Based Optimal Adaptive Output Feedback Control Of A Helicopter Uav, David Nodland, Hassan Zargarzadeh, Sarangapani Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

Helicopter unmanned aerial vehicles (UAVs) are widely used for both military and civilian operations. Because the helicopter UAVs are underactuated nonlinear mechanical systems, high-performance controller design for them presents a challenge. This paper introduces an optimal controller design via an output feedback for trajectory tracking of a helicopter UAV, using a neural network (NN). The output-feedback control system utilizes the backstepping methodology, employing kinematic and dynamic controllers and an NN observer. The online approximator-based dynamic controller learns the infinite-horizon Hamilton-Jacobi-Bellman equation in continuous time and calculates the corresponding optimal control input by minimizing a cost function, forward-in-time, without using the …

Economic Modeling Of Compressed Air Energy Storage, Yang Gu, James D. Mccalley, Ming Ni, Rui Bo

Electrical and Computer Engineering Faculty Research & Creative Works

Due to the variable nature of wind resources, the increasing penetration level of wind power will have a significant impact on the operation and planning of the electric power system. Energy storage systems are considered an effective way to compensate for the variability of wind generation. This paper presents a detailed production cost simulation model to evaluate the economic value of compressed air energy storage (CAES) in systems with large-scale wind power generation. The co-optimization of energy and ancillary services markets is implemented in order to analyze the impacts of CAES, not only on energy supply, but also on system …

Quantum Network Theory Of Computing With Respect To Entangled Flux Qubits And External Perturbation, C. A. Cain, Cheng-Hsiao Wu

Electrical and Computer Engineering Faculty Research & Creative Works

In this work, we attempt to show the differences between traditional qubit-based spintronic methodology for quantum computation and the possible ballistic quantum network implementations. Flux qubits can be considered topologically similar to the persistent currents possessed as the angular momentum in Aharonov-Bohm loops, which can be coupled and thus entangled together. Since entanglement is guaranteed for coupled quantum networks, starting from a point-contacted situation, we first investigate how varying the degree of entanglement strength can affect the superposition of the four possible states for two isolated flux qubits being brought together. In general, the superposition is destroyed once the degree …

Compact Object Coalescence Rate Estimation From Short Gamma-Ray Burst Observations, Carlo Enrico Petrillo, Alexander Dietz, Marco Cavaglia

Physics Faculty Research & Creative Works

Recent observational and theoretical results suggest that short-duration gamma-ray bursts (SGRBs) originate from the merger of compact binary systems of two neutron stars or a neutron star and a black hole. The observation of SGRBs with known redshifts allows astronomers to infer the merger rate of these systems in the local universe. We use data from the SWIFT satellite to estimate this rate to be in the range ∼500-1500 Gpc^-3 yr^-1. This result is consistent with earlier published results which were obtained through alternative approaches. We estimate the number of coincident observations of gravitational-wave signals with SGRBs …

Parameters Influencing Pressure During Pumping Of Self-Compacting Concrete, Dimitri Feys, Geert De Schutter, Ronny Verhoeven

Civil, Architectural and Environmental Engineering Faculty Research & Creative Works

The Main Difference between Conventional Vibrated Concrete (CVC) and Self-Compacting Concrete (SCC) is Observed in the Fresh State, as SCC Has a Significantly Lower Yield Stress. on the Other Hand, the Placement of SCC by Means of Pumping is Done with the Same Equipment and Following the Same Practical Guidelines Developed for CVC. It Can Be Questioned Whether the Flow Behavior in Pipes of SCC is Different and Whether the Developed Practical Guidelines Can Still Be Applied. This Paper Describes the Results of Full-Scale Pumping Tests Carried Out on Several SCC Mixtures. It Shows Primarily that the Slump or Yield …

Data Replication In Cooperative Mobile Ad-Hoc Networks: A Game Theoretic Replication Algorithm Using Volunteers' Dilemma, Dan Hirsch, Sanjay Madria

Computer Science Faculty Research & Creative Works

The mobile computing environment provides many benefits such as ubiquitous access to computing but includes constraints on resources such as available bandwidth and battery life. Replication is a widely recognized method for balancing the demands of storage space with bandwidth and battery life. We propose a novel scheme that seeks to strategically balance these constrained resources through a cooperative game-theory approach for replication in a mobile environment. Our replication strategy relies on the cooperation of the nodes within the network to make replica caching decisions which are spatiotemporally local-optimal for the network from an energy and bandwidth conservation standpoint. In …

Low-Symmetry Monoclinic Ferroelectric Phase Stabilized By Oxygen Octahedra Rotations In Strained Euₓsr₁₋ₓtio₃ Thin Films, Anna N. Morozovska, Yijia Gu, Victoria V. Khist, Maya D. Glinchuk, Long-Qing Chen, For Full List Of Authors, See Publisher's Website.

Materials Science and Engineering Faculty Research & Creative Works

Using Landau-Ginzburg-Devonshire theory and phase-field modeling, we explore the complex interplay between a structural order parameter (oxygen octahedron rotation) and polarization in Eu_xSr_1-xTiO₃ thin films. Under a biaxially tensile strain, a low-symmetry monoclinic phase with in-plane ferroelectric polarization is found to be stabilized by antiferrodistortive oxygen octahedra tilts. The monoclinic phase is stable over a wide temperature range. It is characterized by a large number of energetically equivalent polar and structural twin domains. This work demonstrates the development of a spontaneous polarization and piezo- and pyroelectricity in a ferroelastic twin boundary arising from flexoelectric coupling …

"Shyster" Revisited: Compilation Of Treatments Since My 1982, 1984 Monographs On The Term, Gerald Leonard Cohen

Arts, Languages and Philosophy Faculty Research & Creative Works

No abstract provided.

An Advanced Computational Approach To System Of Systems Analysis & Architecting Using Agent-Based Behavioral Model, Cihan H. Dagli, Nil Ergin, David Lee Enke, Abhijit Gosavi, Ruwen Qin, John Colombi, George Rebovich, Kristin Giammarco, Paulette Acheson, Khaled Haris, Louis Pape Ii

Engineering Management and Systems Engineering Faculty Research & Creative Works

A major challenge to the successful planning and evolution of an acknowledged System of Systems (SoS) is the current lack of understanding of the impact that the presence or absence of a set of constituent systems has on the overall SoS capability. Since the candidate elements of a SoS are fully functioning, stand-alone Systems in their own right, they have goals and objectives of their own to satisfy, some of which may compete with those of the overarching SoS. These system-level concerns drive decisions to participate (or not) in the SoS. Individual systems typically must be requested to join the …

Oscillation Of Third-Order Nonlinear Delay Differential Equations, Ravi P. Agarwal, Martin Bohner, Tongxing Li, Chenghui Zhang

Mathematics and Statistics Faculty Research & Creative Works

In this paper, we study the oscillatory behavior of a class of third-order nonlinear delay differential equations (a(t)(b(t)y′(t)) ′) ′+q(t)yγ(τ(t)) =0. Some new oscillation criteria are presented by transforming this equation to the first order delayed and advanced differential equations. Employing suitable comparison theorems, we establish new results on oscillation of the studied equation. Assumptions in our theorems are less restrictive; these criteria improve those in the recent paper [Appl. Math. Comput., 202 (2008), 102-112] and related contributions to the subject. Examples are provided to illustrate new results.

Dielectric Properties Of Polymer–Particle Nanocomposites Influenced By Electronic Nature Of Filler Surfaces, Sasidhar Siddabattuni, Thomas P. Schuman, Fatih Dogan

Materials Science and Engineering Faculty Research & Creative Works

The interface between the polymer and the particle has a critical role in altering the properties of a composite dielectric. Polymer-ceramic nanocomposites are promising dielectric materials for many electronic and power devices, combining the high dielectric constant of ceramic particles with the high dielectric breakdown strength of a polymer. Self-assembled monolayers of electron rich or electron poor organophosphate coupling groups were applied to affect the filler–polymer interface and investigate the role of this interface on composite behavior. The interface has potential to influence dielectric properties, in particular the leakage and breakdown resistance. The composite films synthesized from the modified filler …

Simulation And Detection Of Unintended Electromagnetic Emissions From Super-Regenerative Receivers, Jake Hertenstein, S. Jagannathan

Electrical and Computer Engineering Faculty Research & Creative Works

A novel method for detecting the presence of the unintended electromagnetic emissions (UEE) from radio receivers is examined without a priori data or training. As an extension of previous research, the behavior of the super-regenerative receiver (SRR) is modeled and simulated with fractional Brownian noise to verify the detection model. This model shows that the presence of noise in the feedback circuit of the SRR is responsible for the characteristic frequency distribution of the receiver's UEE. A second-order self-similarity model is used to estimate the Hurst parameter as a detection threshold for the presence of long-range dependent noise that is …

An Analytical Placement Framework For 3-D Ics And Its Extension On Thermal Awareness, Guojie Luo, Yiyu Shi, Jason Cong

Electrical and Computer Engineering Faculty Research & Creative Works

In this paper, we present a high-quality analytical 3-D placement framework. We propose using a Huber-based local smoothing technique to work with a Helmholtz-based global smoothing technique to handle the nonoverlapping constraints. The experimental results show that this analytical approach is effective for achieving tradeoffs between the wirelength and the through-silicon-via (TSV) number. Compared to the state-of-the-art 3-D placer ntuplace3d, our placer achieves more than 20% wirelength reduction, on average, with a similar number of TSVs. Furthermore, we extend this analytical 3-D placement framework with thermal awareness. While 2-D thermal-aware placement simply follows uniform power distribution to minimize temperature, we …

Modeling And Application Of Multi-Port Tsv Networks In 3-D Ic, Wei Yao, Siming Pan, Brice Achkir, Jun Fan, Lei He

Electrical and Computer Engineering Faculty Research & Creative Works

Through-silicon-via (TSV) enables vertical connectivity between stacked chips or interposer and is a key technology for 3-D integrated circuits (ICs). While arrays of TSVs are needed in 3-D IC, there only exists a frequency-dependent resistance, inductance, conductance and capacitance circuit model for a pair of TSVs with coupling between them. In this paper, we develop a simple yet accurate circuit model for a multiport TSV network (e.g., coupled TSV array) by decomposing the network into a number of TSV pairs and then applying circuit models for each of them. We call the new model a pair-based model for the multiport …

Ff-Bond: Multi-Bit Flip-Flop Bonding At Placement, Chang Cheng Tsai, Yiyu Shi, Guojie Luo, Iris Hui Ru Jiang

Electrical and Computer Engineering Faculty Research & Creative Works

Clock power contributes a significant portion of chip power in modern IC design. Applying multi-bit flip-flops can effectively reduce clock power. State-of-the-artwork performs multi-bit flipflop clustering at the post-placement stage. However, the solution quality may be limited because the combinational gates are immovable during the clustering process. To overcome the deficiency, in this paper, we propose multi-bit flip-flop bonding at placement. Inspired by ionic bonding in Chemistry, we direct flipflops to merging friendly locations thus facilitating flip-flop merging. Experimental results show that our algorithm, called FF-Bond, can save 27% clock power on average. Compared with state-of-the-art post-placement multi-bit flip-flop clustering, …

The Missouri Miner, March 21, 2013

The Missouri Miner Newspaper

No abstract provided.

Faculty Senate Minutes March 21, 2013, Missouri University Of Science And Technology Faculty Senate

Minutes & Agendas

No abstract provided.

Angular Differential Studies Of Electron Transfer In Collisions Of He-Like Ions With Na(3s): The Role Of Electron Saddle Crossings, I. Blank, S. Otranto, C. Meinema, Ronald E. Olson, R. Hoekstra

Physics Faculty Research & Creative Works

We present a systematic experimental and theoretical study of angular differential cross sections of single-electron transfer in collisions of N5 +, O6+, and Ne8+ with ground-state Na(3s) in the collision energy range from 1 to 8 keV/amu. Experiments were performed using recoil-ion momentum spectroscopy in combination with a magneto-optically cooled Na atom target. The results are compared with three-body classical-trajectory Monte Carlo theory. Experimental and theoretical angular differential cross sections for capture into highly excited states show an oscillatory structure which is linked to the number of times the active electron crosses the potential energy saddle, i.e., oscillates between the …

The Missouri Miner, March 14, 2013

The Missouri Miner Newspaper

No abstract provided.

Cold-Formed Steel Bolted Connections Without Washers On Oversized Slotted Holes, Phase 1, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Method Of Purifying Crude Noscapine, Benjamin M. Marshall, Keith Tomazi

Chemical and Biochemical Engineering Faculty Research & Creative Works

The invention provides a method for separating noscapine from an opium source without substantially changing the color of the noscapine.

Specification For The Design Of Cold-Formed Steel Structural Members, American Iron And Steel Institute

American Iron and Steel Institute (AISI) Specifications, Standards, Manuals and Research Reports (1946 - present)

No abstract provided.

Stress Corrosion Cracking Susceptibility Of Ultrafine Grained Al-Mg-Sc Alloy, G. R. Argade, N. Kumar, R. S. Mishra

Materials Science and Engineering Faculty Research & Creative Works

General corrosion and stress corrosion cracking (SCC) behavior of coarse grained, fine grained and ultrafine grained (UFG) AA5083 and Al-Mg-Sc-Zr alloy in different thermomechanical conditions were studied in the present work. Friction stir processing (FSP) was carried out to refine the grain size. The average grain size achieved after FSP for AA5083 was 7±3μm, whereas that for Al-4Mg-0.8Sc-0.08Zr was 0.39±0.16μm with 100% UFG microstructure. Linear polarization resistance and cyclic polarization techniques were used to study general corrosion behavior of these alloys in 3.5wt% NaCl solution. The UFG microstructure showed the highest polarization resistance (Rp) of ~93kΩ which increased to ~160kΩ …

The Missouri Miner, March 7, 2013

The Missouri Miner Newspaper

No abstract provided.

Mechanistic Studies Of Intracellular Delivery Of Proteins By Cell-Penetrating Peptides In Cyanobacteria, Betty Revon Liu, Yue-Wern Huang, Han-Jung Lee

Biological Sciences Faculty Research & Creative Works

Background: The plasma membrane plays an essential role in selective permeability, compartmentalization, osmotic balance, and cellular uptake. The characteristics and functions of cyanobacterial membranes have been extensively investigated in recent years. Cell-penetrating peptides (CPPs) are special nanocarriers that can overcome the plasma membrane barrier and enter cells directly, either alone or with associated cargoes. However, the cellular entry mechanisms of CPPs in cyanobacteria have not been studied.

Results: In the present study, we determine CPP-mediated transduction efficiency and internalization mechanisms in cyanobacteria using a combination of biological and biophysical methods. We demonstrate that both Synechocystis sp. PCC 6803 and Synechococcus …

Immersed Finite Element Methods For Parabolic Equations With Moving Interface, Xiaoming He, Tao Lin, Yanping Lin, Xu Zhang

Mathematics and Statistics Faculty Research & Creative Works

This article presents three Crank-Nicolson-type immersed finite element (IFE) methods for solving parabolic equations whose diffusion coefficient is discontinuous across a time dependent interface. These methods can use a fixed mesh because IFEs can handle interface jump conditions without requiring the mesh to be aligned with the interface. These methods will be compared analytically in the sense of accuracy and computational cost. Numerical examples are provided to demonstrate features of these three IFE methods. © 2012 Wiley Periodicals, Inc.