5,135 research outputs found
A Leaf Recognition Algorithm for Plant Classification Using Probabilistic Neural Network
In this paper, we employ Probabilistic Neural Network (PNN) with image and
data processing techniques to implement a general purpose automated leaf
recognition algorithm. 12 leaf features are extracted and orthogonalized into 5
principal variables which consist the input vector of the PNN. The PNN is
trained by 1800 leaves to classify 32 kinds of plants with an accuracy greater
than 90%. Compared with other approaches, our algorithm is an accurate
artificial intelligence approach which is fast in execution and easy in
implementation.Comment: 6 pages, 3 figures, 2 table
(E)-N-{2-[1-(Benzylimino)ethyl]phenyl}benzamide
In the title compound, C22H20N2O, the molecular conformation is supported by an intramolecular N—H⋯N hydrogen bond, resulting in an almost planar [mean deviation = 0.048 (2) Å] S(6) ring. The dihedral angles between the central benzene ring and the imine- and amide-substituted aromatic rings are 76.6 (2) and 11.7 (2)°, respectively
Suppression of electron spin decoherence of the diamond NV center by a transverse magnetic field
We demonstrate that the spin decoherence of nitrogen vacancy (NV) centers in
diamond can be suppressed by a transverse magnetic field if the electron spin
bath is the primary decoherence source. The NV spin coherence, created in "a
decoherence-free subspace" is protected by the transverse component of the
zero-field splitting, increasing the spin-coherence time about twofold. The
decoherence due to the electron spin bath is also suppressed at magnetic fields
stronger than ~25 gauss when applied parallel to the NV symmetry axis. Our
method can be used to extend the spin-coherence time of similar spin systems
for applications in quantum computing, field sensing, and other metrologies.Comment: 20 pages, 4 figure
Experimental treatment of radiation pneumonitis with human umbilical cord mesenchymal stem cells
AbstractObjectiveTo evaluate of the curative effect of human umbilical cord mesenchymal stem cells (hUC-MSCs) on rat acute radiation pneumonitis.MethodsFourty rats were randomly divided into control group, radiation group, stem cell prevention group, stem cell treatment group and prednisone treatment group. All rats except those in the control group were radiated with X ray to establish the acute radiation pneumonitis damage model. The hUC-MSCs cultured in vitro was administrated to the rats of the prevention group via tail vein (1×106 cells/kg BW) 24 h before the radiation, while the same administration was performed in the rats of the treatment group 24 h after the radiation. After 24 h post the radiation, the rats in the radiation group were given 0.4 mL physiological saline, and those in the prednisone group were given 1 mg/kg prednisone. All rats were observed and executed 72 h after the radiation to detect lung histological changes.ResultsAfter the administration of hUC-MSCs, the survival status of the rats in the prevention group and treatment group was obviously better than that in the control group. As shown by the histological staining, the morphology, proliferation activity and bronchial state of lung tissues were better in the prevention group and treatment group than in the control group.ConclusionsThe hUC-MSCs have definite therapeutic effects on acute radiation pneumonitis in rats
Simulation Analysis on Flow Field and Temperature Field in Mould of Special Thick Slab Caster
A three-dimensional model of the thick slab continuous casting mould of 400 × 2200 mm was established. The effects of immersion depth of nozzle and casting speed on the flow field and temperature field were investigated. The high temperature distribution in mould, the thickness of narrow face solidified shell, the impact position of stream and the free surface velocity were used as the main points of analysis. Simulation and practical water modelling both exhibited the same changing trends, namely, the flow velocity of the surface increases with the distance from nozzle. The scientific basis for optimizing the flow field and temperature field in the continuous casting of special thick slab mould was acquired through calculations
SDSS J013127.34032100.1: A newly discovered radio-loud quasar at with extremely high luminosity
Only very few z>5 quasars discovered to date are radio-loud, with a
radio-to-optical flux ratio (radio-loudness parameter) higher than 10. Here we
report the discovery of an optically luminous radio-loud quasar, SDSS
J013127.34-032100.1 (J0131-0321 in short), at z=5.18+-0.01 using the Lijiang
2.4m and Magellan telescopes. J0131-0321 has a spectral energy distribution
consistent with that of radio-loud quasars. With an i-band magnitude of 18.47
and radio flux density of 33 mJy, its radio-loudness parameter is ~100. The
optical and near-infrared spectra taken by Magellan enable us to estimate its
bolometric luminosity to be L_bol ~ 1.1E48 erg/s, approximately 4.5 times
greater than that of the most distant quasar known to date. The black hole mass
of J0131-0321 is estimated to be 2.7E9 solar masses, with an uncertainty up to
0.4 dex. Detailed physical properties of this high-redshift, radio-loud,
potentially super-Eddington quasar can be probed in the future with more
dedicated and intensive follow-up observations using multi-wavelength
facilities.Comment: 5 pages, 3 figures, accepted to ApJ
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