UScholar Works
 
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CreatorTitleDescriptionSubjectDate
201 Myers, Chris J.Production-passage-time approximation: a new approximation method to accelerate the simulation process of enzymatic reactionsGiven the substantial computational requirements of stochastic simulation, approximation is essential for efficient analysis of any realistic biochemical system. This paper introduces a new approximation method to reduce the computational cost of stochastic simulations of an enzymatic reaction schem...2008-09
202 Freire, Juliana; Silva, Claudio T.Provenance for computational tasks: a surveyThe problem of systematically capturing and managing provenance for computational tasks has recently received significant attention because of its relevance to a wide range of domains and applications. The authors give an overview of important concepts related to provenance management, so that poten...Provenance management; Computational tasks2008-05
203 DeTar, CarletonQCD thermodynamics with 2+1 flavors at nonzero chemical potentialWe present results for the QCD equation of state, quark densities, and susceptibilities at nonzero chemical potential, using 2 + 1 flavor asqtad ensembles with Nt = 4. The ensembles lie on a trajectory of constant physics for which mud ≈ 0:1ms. The calculation is performed using the Taylor expansi...Taylor expansion2008-01
204 Wu, Yong-ShiQuantized spin Hall effect in 3He-A and other p-wave paired Fermi systemsIn this paper, we propose the quantized spin Hall effect (SHE) in the vortex state of a rotating p-wave paired Fermi system in an inhomogeneous magnetic field and in a weak periodic potential. It is the three-dimensional extension of the spin Hall effect for a 3He-A superfluid film previously stud...Fermi systems; Spin Hall conductance2008-04
205 Dawson, KyleRadiation tolerance of fully-depleted P-channel CCDs designed for the SNAP satelliteThick, fully depleted p-channel charge-coupled devices (CCDs) have been developed at the Lawrence Berkeley National Laboratory (LBNL). These CCDs have several advantages over conventional thin, n-channel CCDs, including enhanced quantum efficiency and reduced fringing at near-infrared wavelengths an...P-Channel CCDs; SNAP satellite; Space-based telescopes2008-06
206 Gerton, JordanScattering of plasmons at the intersection of two metallic nanotubes: implications for tunnelingWe study theoretically the plasmon scattering at the intersection of two metallic carbon nanotubes. We demonstrate that, for a small angle of crossing θ « 1, the transmission coefficient is an oscillatory function of θ / λ, where ω is the interaction parameter of the Luttinger liquid in an ind...2008-12
207 Mishchenko, Eugene; Raikh, Mikhail E.Scattering of plasmons at the intersection of two metallic nanotubes: implications for tunnelingWe study theoretically the plasmon scattering at the intersection of two metallic carbon nanotubes. We demonstrate that, for a small angle of crossing θ « 1, the transmission coefficient is an oscillatory function of λ / θ where λ is the interaction parameter of the Luttinger liquid in an indi...2008-12
208 Freire, Juliana; Silva, Claudio T.Scientific exploration in the era of ocean observatoriesSociety's critical and urgent need to better understand the world's oceans is amply documented and has led to a unique convergence of operational and scientific interests in the US, organized around the concept of ocean observatories: cyber-­facilitated integrations of observations, simulations, a...Ocean observatories; Provenance2008-05
209 Sokolsky, PierreSearch for correlations between HiRes stereo events and active galactic nucleiWe have searched for correlations between the pointing directions of ultrahigh energy cosmic rays observed by the High Resolution Fly's Eye experiment and Active Galactic Nuclei (AGN) visible from its northern hemisphere location. No correlations, other than random correlations, have been found.We ...Ultrahigh energy cosmic rays; Anisotropy2008-11
210 Vardeny, Zeev Valentine; Ehrenfreund, Eitan A.Spin-dependent kinetics of polaron pairs in organic light-emitting diodes studied by electroluminescence detected magnetic resonance dynamicsWe describe a method for characterizing the spin-dependent kinetics of polaron pairs (PP) in polymer organic light-emitting diodes (OLEDs) made from a derivative of poly(phenylene-vinylene), using the dynamic response of spin- 1/2 electroluminescence detected magnetic resonance (ELDMR) compared wit...Spin-dependent kinetics; Polaron pairs; Organic light-emitting diodes; OLED; ELDMR; CDMR; Interchain excitations; pi-conjugated polymers2008-11
211 Boehme, ChristophSpin-dependent processes at the crystalline Si-SiO2 interface at high magnetic fieldsAn experimental study on the nature of spin-dependent excess charge-carrier transitions at the interface between (111)-oriented phosphorous-doped ([P]) ~ 1015 cm−3) crystalline silicon and silicon dioxide at high magnetic field (B0~8.5 T) is presented. Electrically detected magnetic-resonance (E...Silicon interfaces; Spin-dependent recombination2008-07
212 Liu, FengSuppression of spin polarization in graphene nanoribbon by edge defects and impuritiesWe investigate the effect of edge defects (vacancies) and impurities (substitutional dopants) on the robustness of spin polarization in graphene nanoribbons (GNRs) with zigzag edges by using density-functional-theory calculations. The stability of the spin state and its magnetic moments is found to ...Edge defects; Vacancy; Spin-polarization; Graphene nanoribbon; GNR2008-04
213 Furse, Cynthia M.System level analysis of noise and interference analysis for a MIMO systemMultiple input multiple output antenna communication system are gaining importance in the field of communication and ad-hoc networks due to increase demand for wireless throughput in band-limited channels. A system analysis is not complete without accounting for the system level noise and interfer...2008-07
214 Liu, FengTheory of directed nucleation of strained islands on patterned substratesWe develop a theoretical model to elucidate the nucleation of strained islands on patterned substrates. We show that island nucleation is directed to the preferred sites by a much lower energy barrier and smaller critical size. Strain relaxation directs island nucleation to the bottom of a pit rat...Directed nucleation; Strained islands; Patterned substrates2008-11
215 Wu, Yong-ShiTwisted supersymmetric invariant formulation of Chern-Simons gauge theory on a latticeWe propose a twisted supersymmetric (SUSY) invariant formulation of the Chern-Simons theory on a Euclidean three-dimensional lattice. The SUSY algebra to be realized on the lattice is the N ¼ 4 D ¼ 3 twisted algebra that was recently proposed by D'Adda et al. In order to keep the manifest anti-Her...Twisted supersymmetry; Chern-Simons gauge theory2008-09
216 Vardeny, Zeev ValentineUltrafast response of surface electromagnetic waves in an aluminum film perforated with subwavelength hole arraysThe ultrafast dynamics of surface electromagnetic waves photogenerated on aluminum film perforated with subwavelength arrays of holes was studied in the visible spectral range by the technique of transient photomodulation with ~100 fs time resolution. We observed a pronounced blueshift of the resona...Subwavelength hole arrays; Nanohole arrays; Transient photomodulation; Plasmonic lattices; Surface electromagnetic waves; SEW; Periodic subwavelength arrays2008-02
217 Christensen, Douglas A.Ultrasound beam propagation using the hybrid angular spectrum methodWe introduce a fast and accurate numerical method for simulating the propagation of an ultrasound beam inside inhomogeneous tissue for mapping beam absorption, refraction and diffraction in the body. The technique, called the hybrid angular spectrum method, is an extension of the angular spectrum m...Ultrasound beam propagation; Medical ultrasound; Inhomogeneous tissue; Beam simulation2008-08
218 Saam, BrianUniversal long-time behavior of nuclear spin decays in a solidMagnetic resonance studies of nuclear spins in solids are exceptionally well suited to probe the limits of statistical physics. We report experimental results indicating that isolated macroscopic systems of interacting nuclear spins possess the following fundamental property: spin decays that start ...Nuclear spin decays; Hyperpolarized solid xenon; Chaos2008-08
219 Khan, Faisal HabibUniversal multilevel DC-DC converter with variable conversion ratio, high compactness factor and limited isolation featureA multilevel dc-dc converter with programmable conversion ratio (CR) is presented in this paper. This converter is a modified version of the MMCCC converter. A universal version of the MMCCC is developed in this paper, and the CR can be easily changed within a wide range. The MMCCC converter is bas...2008-02
220 Freire, Juliana; Silva, Claudio T.VisComplete: automating suggestions for visualization pipelinesBuilding visualization and analysis pipelines is a large hurdle in the adoption of visualization and workflow systems by domain scientists. In this paper, we propose techniques to help users construct pipelines by consensus-automatically suggesting completions based on a database of previously creat...VisComplete; Workflows; Auto completion; Visualization pipelines2008-11
221 Harrison, Reid R.Wireless integrated circuit for 100-channel neural stimulationWe present the design of an integrated circuit for wireless neural stimulation, along with bench-top and in-vivo experimental results. The chip has the ability to drive 100 individual stimulation electrodes with constant-current pulses of varying amplitude, duration, interphasic delay, and repetiti...Wireless; Integrated Neural Interface; Neural recording; Telemetry2008-11
222 Harrison, Reid R.Wireless neural interface for chronic recordingA primary goal of the Integrated Neural Interface Project (INIP) is to develop a wireless, implantable device capable of recording neural activity from 100 micromachined electrodes. The heart of this recording system is a low-power integrated circuit that amplifies 100 weak neural signals, detect...Integrated Neural Interface; Wireless; Neural recording; Telemetry2008-11
223 Harrison, Reid R.Wireless neural signal acquisition with single low-power integrated circuitWe present experimental results from an integrated circuit designed for wireless neural recording applications. The chip, which was fabricated in a 0.6-μm 2P3M BiCMOS process, contains 100 amplifiers and a 10-bit ADC and 902-928 MHz FSK transmitter. Neural signals from one amplifier are sampled by...Low-power; Wireless; Neural recording; Integrated Neural Interface; INI3; Utah Electrode Array2008-05
224 Gerig, GuidoA structural MRI study of human brain development from birth to two yearsBrain development in the first 2 years after birth is extremely dynamic and likely plays an important role in neurodevelopmental disorders, including autism and schizophrenia. Knowledge regarding this period is currently quite limited. We studied structural brain development in healthy subjects from...2008-01-01
225 Simpson, Jamesina J.ADE-FDTD scattered-field formulation for dispersive materialsThis letter presents a scattered-field formulation for modeling dispersive media using the finite-difference time-domain (FDTD) method. Specifically, the auxiliary differential equation method is applied to Drude and Lorentz media for a scattered field FDTD model. The present technique can also be a...2008-01-01
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