1,514 research outputs found
The effects of machining process variables and tooling characterisation on the surface generation: modelling, simulation and application promise
The paper presents a novel approach for modelling and simulation of the surface generation in the machining process. The approach, by integrating dynamic cutting force model, regenerative vibration model, machining system response model and tool profile model, models the complex surface generation process. Matlab Simulink is used to interactively perform the simulation in a user-friendly, effective and efficient manner. The effects of machining variables and tooling characteristics on the surface generation are investigated through simulations. CNC turning trials have been carried out to evaluate and validate the approach and simulations presented. The proposed approach contributes to comprehensive and better understanding of the machining system, and is promising for industrial applications with particular reference to the optimisation of the machining process based on the product/component surface functionality requirements
Waste on the roadside, 'poi-sute' waste: Its distribution and elution potential of pollutants into environment
ArticleWASTE MANAGEMENT. 29(3):1192-1197 (2009)journal articl
Cross-correlation between the 21-cm signal and [OIII] emitters during early cosmic reionization
We study statistics of the 21-cm signal from the epoch of reionization. We
propose to use [OIII] line emitting galaxies to cross-correlate with the 21-cm
signal from . To this aim, we employ simulations of reionization
obtained post-processing the high-resolution cosmological hydrodynamic
simulation Massive Black-II with the three-dimensional (3D) radiative transfer
code CRASH to follow the propagation of ionizing photons from a variety of
sources. We show that, during the early phases of reionization, the 21-cm
signal is positively correlated with the spatial distribution of the [OIII]
emitters on large scales . This positive correlation is
generated by the temperature-galaxy correlation and it is a few times larger
than when we assume that the heating is saturated. As the reionized regions
expand, the correlation changes its sign to negative from to 8. The
signals at this epoch can be detected by combining the Square Kilometre Array
(SKA) and a wide-field [OIII] emitter survey. We also calculate the cross-power
spectrum with a 3D [OIII] intensity field, aiming at exploiting future
intensity mapping observations. We conclude that high-redshift [OIII] line
emitters can be used to probe the reionization process when the intergalactic
medium is largely neutral.Comment: 7 pages, 5 figures, published in MNRA
Geometric Bogomolov conjecture for abelian varieties and some results for those with some degeneration (with an appendix by Walter Gubler: The minimal dimension of a canonical measure)
In this paper, we formulate the geometric Bogomolov conjecture for abelian
varieties, and give some partial answers to it. In fact, we insist in a main
theorem that under some degeneracy condition, a closed subvariety of an abelian
variety does not have a dense subset of small points if it is a non-special
subvariety. The key of the proof is the study of the minimal dimension of the
components of a canonical measure on the tropicalization of the closed
subvariety. Then we can apply the tropical version of equidistribution theory
due to Gubler. This article includes an appendix by Walter Gubler. He shows
that the minimal dimension of the components of a canonical measure is equal to
the dimension of the abelian part of the subvariety. We can apply this result
to make a further contribution to the geometric Bogomolov conjecture.Comment: 30 page
Stability conditions and positivity of invariants of fibrations
We study three methods that prove the positivity of a natural numerical
invariant associated to parameter families of polarized varieties. All
these methods involve different stability conditions. In dimension 2 we prove
that there is a natural connection between them, related to a yet another
stability condition, the linear stability. Finally we make some speculations
and prove new results in higher dimension.Comment: Final version, to appear in the Springer volume dedicated to Klaus
Hulek on the occasion of his 60-th birthda
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