382,787 research outputs found
Optimized Adaptive Control Design and NN based Trajectory Planning for a Class of Wheeled Inverted Pendulum Vehicle Models
Evaluation of ASTER GDEM ver2 using GPS measurements and SRTM ver4.1 in China
The freely available ASTER GDEM ver2 was released by NASA and METI on October 17, 2011. As one of the most complete high resolution digital topographic data sets of the world to date, the ASTER GDEM covers land surfaces between 83°N and 83°S at a spatial resolution of 1 arc-second and will be a useful product for many applications, such as relief analysis, hydrological studies and radar interferometry. The stated improvements in the second version of ASTER GDEM benefit from finer horizontal resolution, offset adjustment and water body detection in addition to new observed ASTER scenes. This study investigates the absolute vertical accuracy of the ASTER GDEM ver2 at five study sites in China using ground control points (GCPs) from high accuracy GPS benchmarks, and also using a DEM-to-DEM comparison with the Consultative Group for International Agriculture Research Consortium for Spatial Information (CGIAR-CSI) SRTM DEM (Version 4.1). And then, the results are separated into GlobCover land cover classes to derive the spatial pattern of error. It is demonstrated that the RMSE (19m) and mean (-13m) values of ASTER GDEM ver2 against GPS-GCPs in the five study areas is lower than its first version ASTER GDEM ver1 (26m and -21m) as a result of the adjustment of the elevation offsets in the new version. It should be noted that the five study areas in this study are representative in terms of terrain types and land covers in China, and even for most of mid-latitude zones. It is believed that the ASTER GDEM offers a major alternative in accessibility to high quality elevation data
Charge Conjugation Violation in Supernovae and The Neutron Shortage for R-Process Nucelosynthesis
Core collapse supernovae are dominated by energy transport from neutrinos.
Therefore, some supernova properties could depend on symetries and features of
the standard model weak interactions. The cross section for neutrino capture is
larger than that for antineutrino capture by one term of order the neutrino
energy over the nucleon mass. This reduces the ratio of neutrons to protons in
the -driven wind above a protoneutron star by approximately 20 % and may
significantly hinder r-process nucleosynthesis.Comment: Proceedings of Intersections Conference, Qube
Enhanced collectivity in neutron-deficient Sn isotopes in energy functional based collective Hamiltonian
The low-lying collective states in Sn isotopes are studied by a
five-dimensional collective Hamiltonian with parameters determined from the
triaxial relativistic mean-field calculations using the PC-PK1 energy density
functional. The systematics for both the excitation energies of states
and values are reproduced rather well, in particular,
the enhanced E2 transitions in the neutron-deficient Sn isotopes with N<66. We
show that the gradual degeneracy of neutron levels 1g7/2 and 2d5/2 around the
Fermi surface leads to the increase of level density and consequently the
enhanced paring correlations from N=66 to 58. It provokes a large quadrupole
shape fluctuation around the spherical shape, and leads to an enhanced
collectivity in the isotopes around N=58.Comment: 5 pages, 4 figures, accepted for publication in Physics Letters
On solutions to the non-Abelian Hirota-Miwa equation and its continuum limits
In this paper, we construct grammian-like quasideterminant solutions of a
non-Abelian Hirota-Miwa equation. Through continuum limits of this non-Abelian
Hirota-Miwa equation and its quasideterminant solutions, we construct a cascade
of noncommutative differential-difference equations ending with the
noncommutative KP equation. For each of these systems the quasideterminant
solutions are constructed as well.Comment: 9 pages, 1 figur
Soft Gluon Resummation Effects in Single Graviton Production at the CERN Large Hadron Collider in the Randall-Sundrum Model
We study QCD effects in single graviton production at the CERN Large Hadron
Collider (LHC) in the Randall-Sundrum (RS) Model. We present in detail the
complete next-to-leading order (NLO) QCD corrections to the inclusive total
cross sections. The NLO QCD corrections enhance significantly the total cross
sections and decrease efficiently the dependence of the total cross sections on
the factorization and renormalization scales. We also examine the uncertainty
of the total cross sections due to the parton distribution function (PDF)
uncertainties. For the differential cross sections on the transverse momentum
() of the graviton, within the CSS resummation formalism, we resum the
logarithmically-enhanced terms at small to all orders up to NLO
logatithmic accuracy. Combined with the fixed order calculations, we give
consistent predictions for both small and large .Comment: 26 pages, 13 figures; minor changes and misprints corrected; version
to appear in PR
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