35,521 research outputs found
Alcoa wind turbines
An overview of Alcoa's wind energy program is given with emphasis on the the development of a low cost, reliable Darrieus Vertical Axis Wind Turbine System. The design layouts and drawings for fabrication are now complete, while fabrication and installation to utilize the design are expected to begin shortly
The twisted Floer homology of torus bundles
Given a torus bundle over the circle and a cohomology class which evaluates nontrivially on the fiber, we compute the
Heegaard Floer homology of with twisted coefficients in the universal
Novikov ring.Comment: 12 pages, 1 figur
Karhunen-Lo\`eve expansion for a generalization of Wiener bridge
We derive a Karhunen-Lo\`eve expansion of the Gauss process , , where is a
standard Wiener process and is a twice continuously
differentiable function with and . This
process is an important limit process in the theory of goodness-of-fit tests.
We formulate two special cases with the function
, , and , ,
respectively. The latter one corresponds to the Wiener bridge over from
to .Comment: 25 pages, 1 figure. The appendix is extende
Constructing solutions to the Bj\"orling problem for isothermic surfaces by structure preserving discretization
In this article, we study an analog of the Bj\"orling problem for isothermic
surfaces (that are more general than minimal surfaces): given a real analytic
curve in , and two analytic non-vanishing orthogonal
vector fields and along , find an isothermic surface that is
tangent to and that has and as principal directions of
curvature. We prove that solutions to that problem can be obtained by
constructing a family of discrete isothermic surfaces (in the sense of Bobenko
and Pinkall) from data that is sampled along , and passing to the limit
of vanishing mesh size. The proof relies on a rephrasing of the
Gauss-Codazzi-system as analytic Cauchy problem and an in-depth-analysis of its
discretization which is induced from the geometry of discrete isothermic
surfaces. The discrete-to-continuous limit is carried out for the Christoffel
and the Darboux transformations as well.Comment: 29 pages, some figure
Approximation of conformal mappings using conformally equivalent triangular lattices
Consider discrete conformal maps defined on the basis of two conformally
equivalent triangle meshes, that is edge lengths are related by scale factors
associated to the vertices. Given a smooth conformal map , we show that it
can be approximated by such discrete conformal maps . In
particular, let be an infinite regular triangulation of the plane with
congruent triangles and only acute angles (i.e.\ ). We scale this
tiling by and approximate a compact subset of the domain of
with a portion of it. For small enough we prove that there exists a
conformally equivalent triangle mesh whose scale factors are given by
on the boundary. Furthermore we show that the corresponding discrete
conformal maps converge to uniformly in with error of
order .Comment: 14 pages, 3 figures; v2 typos corrected, revised introduction, some
proofs extende
Efficiency optimization in a correlation ratchet with asymmetric unbiased fluctuations
The efficiency of a Brownian particle moving in periodic potential in the
presence of asymmetric unbiased fluctuations is investigated. We found that
there is a regime where the efficiency can be a peaked function of temperature,
which proves that thermal fluctuations facilitate the efficiency of energy
transformation, contradicting the earlier findings (H. kamegawa et al. Phys.
Rev. Lett. 80 (1998) 5251). It is also found that the mutual interplay between
asymmetry of fluctuation and asymmetry of the potential may induce optimized
efficiency at finite temperature. The ratchet is not most efficiency when it
gives maximum current.Comment: 10 pages, 7 figure
Modeling pedestrian evacuation movement in a swaying ship
With the advance in living standard, cruise travel has been rapidly expanding
around the world in recent years. The transportation of passengers in water has
also made a rapid development. It is expected that ships will be more and more
widely used. Unfortunately, ship disasters occurred in these years caused
serious losses. It raised the concern on effectiveness of passenger evacuation
on ships. The present study thus focuses on pedestrian evacuation features on
ships. On ships, passenger movements are affected by the periodical water
motion and thus are quite different from the characteristic when walking on
static horizontal floor. Taking into consideration of this special feature, an
agent-based pedestrian model is formulized and the effect of ship swaying on
pedestrian evacuation efficiency is investigated. Results indicated that the
proposed model can be used to quantify the special evacuation process on ships.Comment: Traffic and Granular Flow'15, At Delft, the Netherland
Comment on Bress et al. Effect of Intensive Versus Standard Blood Pressure Treatment According to Baseline Prediabetes Status: A Post Hoc Analysis of a Randomized Trial. Diabetes Care 2017;40:1401-1408.
info:eu-repo/semantics/publishedVersio
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