361 research outputs found
Determining Effective Interface Fracture Properties of 3D Fiber Reinforced Foam Core Sandwich Structures
Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/106494/1/AIAA2013-1547.pd
- nucleus relativistic mean field potentials consistent with kaonic atoms
atomic data are used to test several models of the nucleus
interaction. The t() optical potential, due to coupled channel
models incorporating the (1405) dynamics, fails to reproduce these
data. A standard relativistic mean field (RMF) potential, disregarding the
(1405) dynamics at low densities, also fails. The only successful
model is a hybrid of a theoretically motivated RMF approach in the nuclear
interior and a completely phenomenological density dependent potential, which
respects the low density theorem in the nuclear surface region. This best-fit
optical potential is found to be strongly attractive, with a depth of 180
\pm 20 MeV at the nuclear interior, in agreement with previous phenomenological
analyses.Comment: revised, Phys. Rev. C in pres
Effects of Ply Stacking Sequence in 3D Fiber Reinforced Foam Core Sandwich Structures with Defects
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/140407/1/6.2014-0504.pd
Accurate Crop Spraying with RTK and Machine Learning on an Autonomous Field Robot
The agriculture sector requires a lot of labor and resources. Hence, farmers
are constantly being pressed for technology and automation to be
cost-effective. In this context, autonomous robots can play a very important
role in carrying out agricultural tasks such as spraying, sowing, inspection,
and even harvesting. This paper presents one such autonomous robot that is able
to identify plants and spray agro-chemicals precisely. The robot uses machine
vision technologies to find plants and RTK-GPS technology to navigate the robot
along a predetermined path. The experiments were conducted in a field of potted
plants in which successful results have been obtained.Comment: 7 pages, 12 figures, Journa
The Amplitude of Non-Equilibrium Quantum Interference in Metallic Mesoscopic Systems
We study the influence of a DC bias voltage V on quantum interference
corrections to the measured differential conductance in metallic mesoscopic
wires and rings. The amplitude of both universal conductance fluctuations (UCF)
and Aharonov-Bohm effect (ABE) is enhanced several times for voltages larger
than the Thouless energy. The enhancement persists even in the presence of
inelastic electron-electron scattering up to V ~ 1 mV. For larger voltages
electron-phonon collisions lead to the amplitude decaying as a power law for
the UCF and exponentially for the ABE. We obtain good agreement of the
experimental data with a model which takes into account the decrease of the
electron phase-coherence length due to electron-electron and electron-phonon
scattering.Comment: New title, refined analysis. 7 pages, 3 figures, to be published in
Europhysics Letter
Solitonic approach to the dimerization problem in correlated one-dimensional systems
Using exact diagonalizations we consider self-consistently the lattice
distortions in odd Peierls-Hubbard and spin-Peierls periodic rings in the
adiabatic harmonic approximation. From the tails of the inherent spin soliton
the dimerization d_\infty of regular even rings is found by extrapolations to
infinite ring lengths. Considering a wide region of electron-electron onsite
interaction values U>0 compared with the band width 4t_0 at intermediately
strong electron-phonon interaction g, known relationships obtained by other
methods are reproduced and/or refined within one unified approach: such as the
maximum of d_\infty at U \simeq 3 t_0 for g \simeq 0.5 and its shift to zero
for g \to g_c \approx 0.7. The hyperbolic tangent shape of the spin soliton is
retained for any U and g <~ 0.6. In the spin-Peierls limit the d_\infty are
found to be in agreement with results of DMRG computations.Comment: 4 pages, 4 figures, Physical Review B, Rapid Communications, v. 56
(1997) accepte
Sustainable Urban Transformation and the Green Urban Economy
This chapter explores the connections between the concepts of sustainable urban transformation and the green urban economy, proposes a framework for understanding how these concepts “fit” together, and makes some practical suggestions for local governments (and national and international policy)
Lambda(1405) N to Y N transition in nuclear medium for non-mesonic absorption of Kbar in nucleus
Non-mesonic transition of Lambda(1405) N to YN is investigated as one of the
essential processes for the non-mesonic absorption of Kbar in nuclei. Using
one-meson exchange model in the calculation of the transition, we find that the
non-mesonic transition ratio Gamma_{Lambda N} / Gamma_{Sigma N} depends
strongly on the ratio of the Lambda(1405) (Lambda^*) couplings to Kbar N and pi
Sigma. Especially a larger Lambda^*-Kbar N coupling leads to enhancement of the
transition to Lambda N. Using the chiral unitary model for the description of
the Lambda^*, we obtain Gamma_{Lambda N} / Gamma_{Sigma^{0} N} is approximately
1.2 which is almost independent of the nucleon density, and find the total
non-mesonic decay width of the Lambda^* in uniform nuclear matter to be 22 MeV
at the normal density.Comment: Talk given at 10th International Conference on Hypernuclear and
Strange Particle Physics: Hyp-X, Tokai, Japan, 14-18 Sep 200
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