952 research outputs found
Electronic 4-wheel drive control device
The internal rotation torque generated during operation of a 4-wheel drive vehicle is reduced using a control device whose clutch is attached to one part of the rear-wheel drive shaft. One torque sensor senses the drive torque associated with the rear wheel drive shaft. A second sensor senses the drive torque associated with the front wheel drive shaft. Revolution count sensors sense the revolutions of each drive shaft. By means of a microcomputer, the engagement of the clutch is changed to insure that the ratio of the torque sensors remains constant
Bifurcations and patterns in the Kuramoto model with inertia
In this work, we analyze the Kuramoto model (KM) with inertia on a convergent
family of graphs. It is assumed that the intrinsic frequencies of the
individual oscillators are sampled from a probability distribution. In
addition, a given graph, which may also be random, assigns network
connectivity. As in the original KM, in the model with inertia, the weak
coupling regime features mixing, the state of the network when the phases (but
not velocities) of all oscillators are distributed uniformly around the unit
circle. We study patterns, which emerge when mixing loses stability under the
variation of the strength of coupling. We identify a pitchfork (PF) and an
Andronov-Hopf (AH) bifurcations in the model with multimodal intrinsic
frequency distributions. To this effect, we use a combination of the linear
stability analysis and Penrose diagrams, a geometric technique for studying
stability of mixing. We show that the type of a bifurcation and a nascent
spatiotemporal pattern depend on the interplay of the qualitative properties of
the intrinsic frequency distribution and network connectivity.Comment: 20 pages, 8 figures. Revised version accepted to Journal of Nonlinear
Science. arXiv admin note: text overlap with arXiv:2105.0754
Transparency of 0.2% GdCl3 Doped Water in a Stainless Steel Test Environment
The possibility of neutron and neutrino detection using water Cerenkov
detectors doped with gadolinium holds the promise of constructing very large
high-efficiency detectors with wide-ranging application in basic science and
national security. This study addressed a major concern regarding the
feasibility of such detectors: the transparency of the doped water to the
ultraviolet Cerenkov light. We report on experiments conducted using a 19-meter
water transparency measuring instrument and associated materials test tank.
Sensitive measurements of the transparency of water doped with 0.2% GdCl3 at
337nm, 400nm and 420nm were made using this instrument. These measurements
indicate that GdCl3 is not an appropriate dopant in stainless steel constructed
water Cerenkov detectors.Comment: 17 pages, 11 figures, corrects typos, changes formatting, adds error
bars to figure
Reheating after f(R) inflation
The reheating dynamics after the inflation induced by -corrected
model is considered. To avoid the complexity of solving the fourth order
equations, we analyze the inflationary and reheating dynamics in the Einstein
frame and its analytical solutions are derived. We also perform numerical
calculation including the backreaction from the particle creation and compare
the results with the analytical solutions. Based on the results, observational
constraints on the model are discussed.Comment: 16 pages, 11 figure
Plastic deformations in crystal, polycrystal, and glass in binary mixtures under shear: Collective yielding
Using molecular dynamics simulation, we examine the dynamics of crystal,
polycrystal, and glass in a Lennard-Jones binary mixture composed of small and
large particles in two dimensions. The crossovers occur among these states as
the composition c is varied at fixed size ratio. Shear is applied to a system
of 9000 particles in contact with moving boundary layers composed of 1800
particles. The particle configurations are visualized with a sixfold
orientation angle alpha_j(t) and a disorder variable D_j(t) defined for
particle j, where the latter represents the deviation from hexagonal order.
Fundamental plastic elements are classified into dislocation gliding and grain
boundary sliding. At any c, large-scale yielding events occur on the acoustic
time scale. Moreover, they multiply occur in narrow fragile areas, forming
shear bands. The dynamics of plastic flow is highly hierarchical with a wide
range of time scales for slow shearing. We also clarify the relationship
between the shear stress averaged in the bulk region and the wall stress
applied at the boundaries.Comment: 17 pages, 15 figures, to appear in Physical Review
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