Search results for "FIX"
showing 10 items of 1335 documents
Two Reflected Gray Code-Based Orders on Some Restricted Growth Sequences
2014
We consider two order relations: that induced by the m-ary reflected Gray code and a suffix partitioned variation of it. We show that both of them when applied to some sets of restricted growth sequences still yield Gray codes. These sets of sequences are: subexcedant and ascent sequences, restricted growth functions and staircase words. In particular, we give the first suffix partitioned Gray codes for restricted growth f unctions and ascent sequences; these latter sequences code various combinatorial classes as interval orders, upper triangular matrices without zero rows and zero columns whose non-negative integer entries sum up to n, and certain pattern-avoiding permutations. For each Gr…
Carbon dioxide conversion to dimethyl carbonate: The effect of silica as support for SnO2 and ZrO2 catalysts
2011
International audience; Abundant in nature, CO2 poses few health hazards and consequently is a promising alternative to phosgene feedstock according with the principles of Green Chemistry and Engineering. The synthesis organic carbonates from CO2 instead of phosgene is highly challenging as CO2 is much less reactive. As part of our ongoing research on the investigation of catalysts for dimethyl carbonate (DMC) synthesis from methanol and CO2, we herein report results aimed at comparing the catalytic behavior of new SnO2-based catalysts with that of ZrO2. Silica-supported SnO2 and ZrO2 exhibit turnover numbers which are an order of magnitude higher than those of the unsupported oxides. Tin-b…
The efficiency of lead thyroid shield in trauma surgery
1997
Die Strahlenbelastung der Operateure bei unfallchirurgischen Eingriffen hat in den letzten Jahren durch den Trend zu biologischen Osteosyntheseverfahren, insbesondere der Marknagelung, zugenommen, da geschlossene Reposition und distale Verriegelung radiologisch kontrolliert werden. Wir wollten jetzt uberprufen, welchen Einflus der Schilddrusenbleischutz auf die Strahlenbelastung der Operateure bei operativen Eingriffen an den unteren Extremitaten hat. Mit Hilfe eines Unterschenkelphantoms wurden unterschiedliche intraoperative Durchleuchtungssituationen simuliert und die Strahlenbelastung der Schilddruse mit und ohne Bleischutz des Operateurs uber ein Dosismesgerat (Szintomat) festgestellt.…
Mundhygiene und Ernährungsgewohnheiten bei Jugendlichen mit festsitzenden kieferorthopädischen Apparaturen
2012
Eine Vielzahl an Studien belegen, dass festsitzende kieferorthopadische Behandlungsmasnahmen (Multiband- oder Multibracket-Apparaturen) eine temporare Verschlechterung der Mundhygiene mit entsprechenden entzundlich bedingten Gingivaveranderungen hervorrufen konnen. Optimale Mundhygienemasnahmen und Anderungen der Ernahrungsgewohnheiten sind wesentliche Faktoren, um parodontale Entzundungen bei festsitzenden kieferorthopadischen (KFO-) Apparaturen zu vermeiden. In der vorliegenden Studie sollte uberpruft werden, inwieweit die Empfehlungen der behandelnden Kieferorthopaden von jugendlichen Patienten nachvollzogen werden. Insgesamt wurden 67 jugendliche Patienten mit festsitzenden KFO-Apparatu…
On the linear friction welding process of aluminum alloys: Experimental insights through process monitoring
2013
Abstract Linear friction welding is a solid-state joining process for non-axisymmetric components in which joining of materials is obtained through the relative motion of two components under pressure. In the process the heat source is given by the frictional forces work decaying into heat determining a local softening of the material and eventually bonding conditions. A dedicated fixture was equipped with sensors for the in-process acquisition of variables regarding kinematics, dynamics and temperature levels. The results of an experimental campaign aimed to weld AA6082-T6 aluminum alloy parts are presented and a process window is identified for the used alloy.
Spatially localized solutions of the Hammerstein equation with sigmoid type of nonlinearity
2016
Abstract We study the existence of fixed points to a parameterized Hammerstein operator H β , β ∈ ( 0 , ∞ ] , with sigmoid type of nonlinearity. The parameter β ∞ indicates the steepness of the slope of a nonlinear smooth sigmoid function and the limit case β = ∞ corresponds to a discontinuous unit step function. We prove that spatially localized solutions to the fixed point problem for large β exist and can be approximated by the fixed points of H ∞ . These results are of a high importance in biological applications where one often approximates the smooth sigmoid by discontinuous unit step function. Moreover, in order to achieve even better approximation than a solution of the limit proble…
Constraints on Conformal Windows from Holographic Duals
2009
We analyze a beta function with the analytic form of Novikov-Shifman-Vainshtein-Zakharov result in the five dimensional gravity-dilaton environment. We show how dilaton inherits poles and fixed points of such beta function through the zeros and points of extremum in its potential. Super Yang-Mills and supersymmetric QCD are studied in detail and Seiberg's electric-magnetic duality in the dilaton potential is explicitly demonstrated. Non-supersymmetric proposals of similar functional form are tested and new insights into the conformal window as well as determinations of scheme-independent value of the anomalous dimension at the fixed point are presented.
Wilson Loop Form Factors: A New Duality
2017
We find a new duality for form factors of lightlike Wilson loops in planar $\mathcal N=4$ super-Yang-Mills theory. The duality maps a form factor involving an $n$-sided lightlike polygonal super-Wilson loop together with $m$ external on-shell states, to the same type of object but with the edges of the Wilson loop and the external states swapping roles. This relation can essentially be seen graphically in Lorentz harmonic chiral (LHC) superspace where it is equivalent to planar graph duality. However there are some crucial subtleties with the cancellation of spurious poles due to the gauge fixing. They are resolved by finding the correct formulation of the Wilson loop and by careful analyti…
Operator product expansion coefficients in the exact renormalization group formalism
2020
We study how to compute the operator product expansion coefficients in the exact renormalization group formalism. After discussing possible strategies, we consider some examples explicitly, within the $\epsilon$-expansions, for the Wilson-Fisher fixed points of the real scalar theory in $d=4-\epsilon$ dimensions and the Lee-Yang model in $d=6-\epsilon$ dimensions. Finally we discuss how our formalism may be extended beyond perturbation theory.
Bimetric truncations for quantum Einstein gravity and asymptotic safety
2010
In the average action approach to the quantization of gravity the fundamental requirement of "background independence" is met by actually introducing a background metric but leaving it completely arbitrary. The associated Wilsonian renormalization group defines a coarse graining flow on a theory space of functionals which, besides the dynamical metric, depend explicitly on the background metric. All solutions to the truncated flow equations known to date have a trivial background field dependence only, namely via the classical gauge fixing term. In this paper we analyze a number of conceptual issues related to the bimetric character of the gravitational average action and explore a first no…