Observability of quality features of sheet metal parts based on metamodels

Deep drawn sheet metal parts are increasingly designed to the feasibility limit, thus achieving a robust process is often challenging. The fluctuation of process and material properties often leads to robustness problems. Especially skid impact lines can cause visible changes of the surface fine structure even after painting. Numerical simulations are used to detect critical regions and the influences on the skid impact lines. To enhance the agreement with the real process conditions, the measured material data and the force distribution are taken into account. The simulation metamodel contains the virtual knowledge of a particular forming process, which is determined based on a series of finite element simulations with variable input parameters. Based on these metamodels, innovative process windows can be displayed to determine the influences on the critical regions and on skid impact lines. By measuring the draw-in of the part, sensor positions can be identified. Each sensor observes the accordant quality criterion and is hence able to quantify potential splits, insufficient stretching, wrinkles or skid impact lines. Furthermore the virtual draw-in sensors and quality criteria are particularly useful for the assessment of the process observation of a subsequent process control

Compact vortex in a generalized Born-Infeld model

We study vortexlike solutions in a generalized Born-Infeld model. The model is driven by two distinct parameters, one which deals with the Born-Infeld term, and the other, which controls the presence of high-order power term in the covariant derivative of the Higgs field. We numerically solve the equations of motion and depict the main vortex features, for several values of the two parameters of the model. The results indicate the presence of compact vortex, when the parameter responsible for the high-order power in the derivative increases to sufficiently large values.Comment: 6 pages, 6 figures; version to appear in PR

Twinlike Models for Self-Dual Maxwell-Higgs Theories

In this work we present a theoretical framework that allows for the existence of coherent twinlike models in the context of self-dual Maxwell-Higgs theories. We verify the consistence of this framework by using it to develop some twinlike self-dual Maxwell-Higgs models. We use a combination of theoretical and numerical techniques to show that these models exhibit the very same topological BPS structures, including their field configurations and total energy. The study shows that it is possible to develop a completely consistent prescription, which extends the idea of twinlike models to the case of vortices in Maxwell-Higgs theories.Comment: 7 pages, 3 figures; version to appear in PR

Topological vortices in generalized Born-Infeld-Higgs electrodynamics

A consistent BPS formalism to study the existence of topological axially symmetric vortices in generalized versions of the Born-Infeld-Higgs electrodynamics is implemented. Such a generalization modifies the field dynamics via introduction of three non-negative functions depending only in the Higgs field, namely, $G(|\phi|)$, $w(|\phi|)$ and $V(|\phi|)$. A set of first-order differential equations is attained when these functions satisfy a constraint related to the Ampere law. Such a constraint allows to minimize the system energy in such way that it becomes proportional to the magnetic flux. Our results provides an enhancement of topological vortex solutions in Born-Infeld-Higgs electrodynamics. Finally, we analyze a set of models such that a generalized version of Maxwell-Higgs electrodynamics is recovered in a certain limit of the theory.Comment: 8 pages, 8 figures, to appear in EPJ

Nontopological self-dual Maxwell-Higgs vortices

We study the existence of self-dual nontopological vortices in generalized Maxwell-Higgs models recently introduced in Ref. \cite{gv}. Our investigation is explicitly illustrated by choosing a sixth-order self-interaction potential, which is the simplest one allowing the existence of nontopological structures. We specify some Maxwell-Higgs models yielding BPS nontopological vortices having energy proportional to the magnetic flux, $\Phi_{B}$, and whose profiles are numerically achieved. Particularly, we investigate the way the new solutions approach the boundary values, from which we verify their nontopological behavior. Finally, we depict the profiles numerically found, highlighting the main features they present.Comment: 6 pages, 4 figure

Long beating wavelength in the Schwarz-Hora effect

Thirty years ago, H.Schwarz has attempted to modulate an electron beam with optical frequency. When a 50-keV electron beam crossed a thin crystalline dielectric film illuminated with laser light, electrons produced the electron-diffraction pattern not only at a fluorescent target but also at a nonfluorescent target. In the latter case the pattern was of the same color as the laser light (the Schwarz-Hora effect). This effect was discussed extensively in the early 1970s. However, since 1972 no reports on the results of further attempts to repeat those experiments in other groups have appeared, while the failures of the initial such attempts have been explained by Schwarz. The analysis of the literature shows there are several unresolved up to now contradictions between the theory and the Schwarz experiments. In this work we consider the interpretation of the long-wavelength spatial beating of the Schwarz-Hora radiation. A more accurate expression for the spatial period has been obtained, taking into account the mode structure of the laser field within the dielectric film. It is shown that the discrepancy of more than 10% between the experimental and theoretical results for the spatial period cannot be reduced by using the existing quantum models that consider a collimated electron beam.Comment: 3 pages, RevTe

Geology of the Parliament Buildings 6. Geology of the British Columbia Parliament Buildings, Victoria

The British Columbia parliament buildings were constructed in two stages: the first building was started in 1893 and officially opened in 1898; the addition was started in 1912 and completed in 1915. The primary external building stone is a fine-grained, light grey, dacitic volcanic rock, commonly called Haddington Island andesite. The foundation and lower courses are mediumgrained, grey, salt-and-pepper granodiorite, called Nelson Island granite. The Haddington Island andesite was also used for exterior architectural ornaments and statues. A variety of marbles from the USA and Italy decorate the interior of the buildings. Several monuments and fountains within the legislature precinct display a variety of both imported and local provenance building stones. This article presents a brief history of the parliament buildings and their construction, a description of the building stones, and an overview of a century-long performance record of the exterior building stones, which have long resisted the effects of British Columbia coastal weather. SOMMAIRE Les édifices du parlement de Colombie-Britannique ont été construits en deux étapes : la construction du premier édifice a débuté en 1893 et il a été inauguré en 1898; la construction d'un ajout a débuté en 1912 et a été complété en 1915. La pierre de construction du parement du bâtiment initial est une roche volcanique dacitique gris pâle à grains fins, communément appelée andésite de l'île Haddington. La fondation et les assisses inférieures sont formées de blocs d'une granodiorite tachetée grise à grains moyens appelée granite de l'île Nelson. L'andésite de l'île Haddington a également été utilisée pour les statues et l'ornement architectural. Des marbres variés des États-Unis et d'Italie décorent l'intérieur des édifices. Plusieurs fontaines et monuments de l'enceinte législative sont faits de pierre de construction d'origine diverse. L'article qui suit présente une histoire abrégée des édifices du parlement et de leur construction, une description des pierres de constructions, ainsi qu'un aperçu de la durabilité centenaire des pierres de construction extérieures, lesquelles résistent depuis longtemps au climat côtier de la Colombie-Britannique

Deformed self-dual magnetic monopoles

We develop a deformation method for attaining new magnetic monopole analytical solutions consistent with generalized Yang-Mills-Higgs model introduced recently. The new solutions fulfill the usual radially symmetric ansatz and the boundary conditions suitable to assure finite energy configurations. We verify our prescription by studying some particular cases involving both exactly and partially analytical initial configurations whose deformation leads to new analytic BPS monopoles. The results show consistency among the models, the deformation procedure and the profile of the new solutions.Comment: 7 pages, 3 figure

"Colliding beam" enhancement mechanism of deuteron-deuteron fusion reactions in matter

We suggest a ``ping-pong'' mechanism of enhancement for fusion reactions between a low energy external deuteron beam and the deuterons in a condensed matter or molecular target. The mechanism is based on the possibility of acceleration of a target deuteron by the Coulomb field of a projectile deuteron with its subsequent rebound from a heavy atom in matter and the following fusion of the two deuterons moving towards each other. This effectively converts the fixed target process into a colliding beam reaction. In a simple limiting case this reduces the negative penetrability exponent by a factor of $\sqrt{2}$. We also discuss a contribution given by ``zero oscillations'' of a bound target deuteron. The proposed mechanism is expected to be efficient in compounds with target deuterons localized in the vicinity of heavy atoms.Comment: 4 page