7,872 research outputs found
Formation of an Edge Striped Phase in Fractional Quantum Hall Systems
We have performed an exact diagonalization study of up to N=12 interacting
electrons on a disk at filling for both Coulomb and
short-range interaction for which Laughlin wave function is the exact solution.
For Coulomb interaction and we find persistent radial oscillations
in electron density, which are not captured by the Laughlin wave function. Our
results srongly suggest formation of a chiral edge striped phase in quantum
Hall systems. The amplitude of the charge density oscillations decays slowly,
perhaps as a square root of the distance from the edge; thus the spectrum of
edge excitations is likely to be affected.Comment: 4 pages, 3 Figs. include
Photographic style transfer
© 2018, The Author(s). Image style transfer has attracted much attention in recent years. However, results produced by existing works still have lots of distortions. This paper investigates the CNN-based artistic style transfer work specifically and finds out the key reasons for distortion coming from twofold: the loss of spatial structures of content image during content-preserving process and unexpected geometric matching introduced by style transformation process. To tackle this problem, this paper proposes a novel approach consisting of a dual-stream deep convolution network as the loss network and edge-preserving filters as the style fusion model. Our key contribution is the introduction of an additional similarity loss function that constrains both the detail reconstruction and style transfer procedures. The qualitative evaluation shows that our approach successfully suppresses the distortions as well as obtains faithful stylized results compared to state-of-the-art methods
Microheated substrates for patterning cells and controlling development
Here, we seek to control cellular development by devising a means through which cells can be subjected to a microheated environment in standard culture conditions. Numerous techniques have been devised for controlling cellular function and development via manipulation of surface environmental cues at the micro- and nanoscale. It is well understood that temperature plays a significant role in the rate of cellular activities, migratory behavior (thermotaxis), and in some cases, protein expression. Yet, the effects and possible utilization of micrometer-scale temperature fields in cell cultures have not been explored. Toward this end, two types of thermally isolated microheated substrates were designed and fabricated, one with standard backside etching beneath a dielectric film and another with a combination of surface and bulk micromachining and backside etching. The substrates were characterized with infrared microscopy, finite element modeling, scanning electron microscopy, stylus profilometry, and electrothermal calibrations. Neuron culture studies were conducted on these substrates to 1) examine the feasibility of using a microheated environment to achieve patterned cell growth and 2) selectively accelerate neural development on regions less than 100wide. Results show that attached neurons, grown on microheated regions set at 37, extended processes substantially faster than those incubated at 25on the same substrate. Further, unattached neurons were positioned precisely along the length of the heater filament (operating at 45) using free convection currents. These preliminary findings indicate that microheated substrates may be used to direct cellular development spatially in a practical manner.$hfillhbox[1414]
Novel nanorod precipitate formation in neodymium and titanium codoped bismuth ferrite
The discovery of unusual nanorod precipitates in bismuth ferrite doped with Nd and Ti is reported. The atomic structure and chemistry of the nanorods are determined using a combination of high angle annular dark field imaging, electron energy loss spectroscopy, and density functional calculations. It is found that the structure of the BiFeO3 matrix is strongly modified adjacent to the precipitates; the readiness of BiFeO3 to adopt different structural allotropes in turn explains why such a large axial ratio, uncommon in precipitates, is stabilized. In addition, a correlation is found between the alignment of the rods and the orientation of ferroelastic domains in the matrix, which is consistent with the system's attempt to minimize its internal strain. Density functional calculations indicate a finite density of electronic states at the Fermi energy within the rods, suggesting enhanced electrical conductivity along the rod axes, and motivating future investigations of nanorod functionalities
Polarized beam operation of the Hybrid Spectrometer at the pulsed Spallation Neutron Source
The concept of a neutron Hybrid Spectrometer (HYSPEC) combines the
time-of-flight spectroscopy with the focusing Bragg optics and incorporates a
polarized beam option. Here we describe the polarization analysis scheme
proposed for HYSPEC and quantify its performance via the Monte-Carlo
simulations. We find that the broadband supermirror-bender transmission
polarizers provide reasonably good polarization analysis capability within
about 8-10 meV energy window for scattered neutron energies in the thermal
range up to about 25 meV.Comment: Preprint, to appear in Physica B. 10 pages, 4 figure
Virtual Spring- Damper Mesh-Based Formation Control for Spacecraft Swarms in Potential Fields
A theorem for the beam splitter entangler
It is conjectured that the an entanglement output states from a beam splitter
requires the nonclassicality in the input state(M.S. Kim, W. Son, V. Buzek and
P. L. Knight, Phys. Rev. A, 65, 032323(2002)). Here we give a proof for this
conjecture.Comment: Two relevant literatures added. To appear in Phys. Rev.
Characterization of the microstructure transition during the solidification of metal alloys under the influence of external forces
Does property market risks matter in commercial mortgage loan pricing : an inquiry into the determinants of commercial mortgage loan spread
Thesis (S.M. in Real Estate Development)--Massachusetts Institute of Technology, Dept. of Urban Studies and Planning, 2007.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.Includes bibliographical references (leaves 51-52).The study takes a quantitative approach to test the determinants of commercial mortgage loan pricing at origination. The determinants include capital market risk, property market risks, mortgage terms and property characteristics. Taken into consideration of the endogenous factor between loan spread and LTV ratio, we use the OLS and 2SLS model to examine the variables of driving the spread and LTV and the interaction between them. The conclusion is drawn that there is little linkage between property market risks and commercial mortgage loan spread at origination. Therefore, commercial mortgage is mispriced in terms of property market risks.by Xin Wang & Hongfei Chen.S.M.in Real Estate Developmen
Properties of a beam splitter entangler with Gaussian input states
An explicit formula is given for the quantity of entanglement in the output
state of a beam splitter, given the squeezed vacuum states input in each mode.Comment: To appear in Phys. Rev.
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