180,758 research outputs found
-Springer varieties and Hall-Littlewood polynomials
No full textThe -Springer varieties are a generalization of Springer fibers
introduced by Levinson, Woo, and the author that have connections to the Delta
Conjecture from algebraic combinatorics. We prove a positive Hall-Littlewood
expansion formula for the graded Frobenius characteristic of the cohomology
ring of a -Springer variety. We do this by interpreting the Frobenius
characteristic in terms of counting points over a finite field
and partitioning the -Springer variety into copies of Springer fibers
crossed with affine spaces. As a special case, our proof method gives a
geometric meaning to a formula of Haglund, Rhoades, and Shimozono for the
Hall-Littlewood expansion of the symmetric function in the Delta Conjecture at
.Comment: 21 page
Cocharge and skewing formulas for -Springer modules and the Delta Conjecture
No full textWe prove that , the symmetric function in
the Delta Conjecture at , is a skewing operator applied to a
Hall-Littlewood polynomial, and generalize this formula to the Frobenius series
of all -Springer modules. We use this to give an explicit Schur
expansion in terms of the Lascoux-Sch\"utzenberger cocharge statistic on a new
combinatorial object that we call a \textit{battery-powered tableau}. Our proof
is geometric, and shows that the -Springer varieties of Levinson, Woo,
and the second author are generalized Springer fibers coming from the partial
resolutions of the nilpotent cone due to Borho and MacPherson.
We also give alternative combinatorial proofs of our Schur expansion for
several special cases, and give conjectural skewing formulas for the and
coefficients of .Comment: Section 7 has been added, title update
Book reviews" "Boris S. Mordukhovich; Variational Analysis and Applications", Springer Monographs in Mathematics. Springer, Cham, 2018. xix+622 p. ISBN: 978-3-319-92773-2/hbk; 978-3-319-92775-6/ebook.
No full textAlthough variational principles in mathematical physics and mechanics were known since the 18th century, variational analysis, in its current acceptance, is a relatively new discipline. Its aim is to treat optimization and control problems via perturbations, approximations and generalized differentiation of nonsmooth or set- valued maps. As the author mentions in Preface, the first monograph dedicated to variational analysis in finite dimensions is that by R. T. Rockafellar and R. J.B. Wets, Springer 1998, where this very name was coined. The infinite-dimensional case is treated at large in the impressive two-volume monograph of the author, Variational analysis and generalized differentiation. I: Basic theory (579 p), II: Applications (610 p), Springer 2006 (a review of these volumes is published in vol. 52 (2007), no. 1, of the present journal)
Connector algebras for C/E and P/T nets interactions
No full textA quite flourishing research thread in the recent literature on component based system is concerned with the algebraic properties of different classes of connectors. In a recent paper, an algebra of stateless connectors was presented that consists of five kinds of basic connectors, namely symmetry, synchronization, mutual exclusion, hiding and inaction, plus their duals and it was shown how they can be freely composed in series and in parallel to model sophisticated "glues". In this paper we explore the expressiveness of stateful connectors obtained by adding one-place buffers or unbounded buffers to the stateless connectors. The main results are: i) we show how different classes of connectors exactly correspond to suitable classes of Petri nets equipped with compositional interfaces, called nets with boundaries; ii) we show that the difference between strong and weak semantics in stateful connectors is reflected in the semantics of nets with boundaries by moving from the classic step semantics (strong case) to a novel banking semantics (weak case), where a step can be executed by taking some "debit" tokens to be given back during the same step; iii) we show that the corresponding bisimilarities are congruences (w.r.t. composition of connectors in series and in parallel); iv) we show that suitable monoidality laws, like those arising when representing stateful connectors in the tile model, can nicely capture concurrency aspects; and v) as a side result, we provide a basic algebra, with a finite set of symbols, out of which we can compose all P/T nets, fulfilling a long standing quest
Immune Response Model Fitting to CD4 T Cell Data in Lymphocytic Choriomeningitis Virus LCMV infection
No full textWe make two fits of an ODE system with 5 equations that model immune response by CD4 + T cells with the presence of regulatory T cells (Tregs). We fit the simulations to data regarding gp61 and NP309 epitopes from mice infected with lymphocytic choriomeningitis virus LCMV. We optimized parameters relating to: the T cell maximum growth rate; the T cell capacity; the T cell homeostatic level; and the ending time of the immune activation phase after infection. We quantitatively and qualitatively compare the obtained results with previous fits in the literature using different ODE models and we show that we are able to calibrate the model and obtain good fits describing the data. (c) 2021, Springer Nature Switzerland AG
L.P. Hildebrand, L.W. Brigham, and T.M. Johansson (eds.), Sustainable Shipping in a Changing Arctic (WMU Studies in Maritime Affairs, 7) (Cham: Springer, 2018)
No full textA review of the book: Hildebrand, L. P., Brigham, L. W., & Johansson, T. M. (eds.), Sustainable Shipping in a Changing Arctic (WMU Studies in Maritime Affairs, 7) (Cham: Springer, 2018
Measurement of the top-quark mass in all-jets events in pp collisions at = 7 TeV
No full textThe mass of the top quark is measured using a sample of candidate events with at least six jets in the final state. The sample is selected from data collected with the CMS detector in pp collisions at = 7 TeV in 2011 and corresponds to an integrated luminosity of 3.54 . The mass is reconstructed for each event employing a kinematic fit of the jets to a hypothesis. The top-quark mass is measured to be 173.49 0.69(stat.) 1.21(syst.) GeV. A combination with previously published measurements in other decay modes by CMS yields a mass of 173.54 0.33(stat.) 0.96(syst.) GeV
Measuring industry-science links through inventor-author relations: A profiling method
No full textIn this pilot study we examine the performance of text-based profiling in recovering a set of validated inventor-author links. In a first step we match patents and publications solely based on their similarity in content. Next, we compare inventor and author names on the highest ranked matches for the occurrence of name matches. Finally, we compare these candidate matches with the names listed in a validated set of inventor-author names. Our text-based profile methodology performs significantly better than a random matching of patents and publications, suggesting that text-based profiling is a valuable complementary tool to the name searches used in previous studies.innovation; industry-science links; text-based profiling;
Carleson measures, trees, extrapolation, and T(b) theorems
No full textThe theory of Carleson measures, stopping time arguments, and atomic decompositions has been well-established in harmonic analysis. More recent is the theory of phase space analysis from the point of view of wave packets on tiles, tree selection algorithms, and tree size estimates. The purpose of this paper is to demonstrate that the two theories are in fact closely related, by taking existing results and reproving them in a unified setting. In particular we give a dyadic version of extrapolation for Carleson measures, as well as a two-sided local dyadic T(b) theorem which generalizes earlier T(b) theorems of David, Journé, Semmes, and Christ
Measurement of the ratio of prompt χ c to J / ψ production in pp collisions at √s = 7 TeV
No full textThe prompt production of charmonium χ c and J / ψ states is studied in proton-proton collisions at a centre-of-mass energy of √s = 7 TeV at the Large Hadron Collider. The χ c and J / ψ mesons are identified through their decays χ c → J / ψ γ and J / ψ → μ + μ - using 36 pb - 1 of data collected by the LHCb detector in 2010. The ratio of the prompt production cross-sections for χ c and J / ψ, σ (χ c → J / ψ γ) / σ (J / ψ), is determined as a function of the J / ψ transverse momentum in the range 2 < p T J / ψ < 15 GeV / c. The results are in excellent agreement with next-to-leading order non-relativistic expectations and show a significant discrepancy compared with the colour singlet model prediction at leading order, especially in the low p T J / ψ region
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