Search results for " moduli"

Chern classes of the moduli stack of curves

2005

Here we calculate the Chern classes of ${\bar {\mathcal M}}_{g,n}$, the moduli stack of stable n-pointed curves. In particular, we prove that such classes lie in the tautological ring.

Hurwitz spaces of quadruple coverings of elliptic curves and the moduli space of abelian threefolds A_3(1,1,4)

2005

We prove that the moduli space A_3(1,1,4) of polarized abelian threefolds with polarization of type (1,1,4) is unirational. By a result of Birkenhake and Lange this implies the unirationality of the isomorphic moduli space A_3(1,4,4). The result is based on the study the Hurwitz space H_{4,n}(Y) of quadruple coverings of an elliptic curve Y simply branched in n points. We prove the unirationality of its codimension one subvariety H^{0}_{4,A}(Y) which parametrizes quadruple coverings ��:X --> Y with Tschirnhausen modules isomorphic to A^{-1}, where A\in Pic^{n/2}Y, and for which ��^*:J(Y)--> J(X) is injective. This is an analog of the result of Arbarello and Cornalba that the Hurwitz s…

Hurwitz spaces of triple coverings of elliptic curves and moduli spaces of abelian threefolds

2002

We prove that the moduli spaces A_3(D) of polarized abelian threefolds with polarizations of types D=(1,1,2), (1,2,2), (1,1,3) or (1,3,3) are unirational. The result is based on the study of families of simple coverings of elliptic curves of degree 2 or 3 and on the study of the corresponding period mappings associated with holomorphic differentials with trace 0. In particular we prove the unirationality of the Hurwitz space H_{3,A}(Y) which parameterizes simply branched triple coverings of an elliptic curve Y with determinants of the Tschirnhausen modules isomorphic to A^{-1}.

Componenti di un impianto fotovoltaico

2013

A combinatorial algorithm related to the geometry of the moduli space of pointed curves

2002

As pointed out in Arbarello and Cornalba ( J. Alg. Geom. 5 (1996), 705–749), a theorem due to Di Francesco, Itzykson, and Zuber (see Di Francesco, Itzykson, and Zuber, Commun. Math. Phys. 151 (1993), 193–219) should yield new relations among cohomology classes of the moduli space of pointed curves. The coefficients appearing in these new relations can be determined by the algorithm we introduce in this paper.

EMERGENZA SANITARIA E TEMPORANEAITÀ

2018

Fornire risposte immediate a una modernità sempre più rivolta al rapido consumo ha dato origine a un’architettura maggiormente indirizzata alla produzione di manu- fatti provvisori e mobili. Il progetto si appropria così del tempo e ne controlla il suo stato, divenendo strumento indispensabile per rispondere a realtà in continuo divenire, spesso soggette a trasformazioni violente e repentine, come quelle generate da calamità naturali e dagli esodi conseguenti a guerre o a traumi politici, dando vi- ta a nuove forme e sistemi appartenenti a un’Architettura temporanea che potremo definire sanitaria. L’Emergenza sanitaria è una realtà ormai presente nel panorama politico, economico e sociale d…

CRM sistēmas ieviešana uzņēmumā "North Technology Group"

2021

Bakalaura darba tēma ir “CRM sistēmas ieviešana uzņēmumā “North Technology Group””. Darba mērķis ir konstatēt klientu attiecību pārvaldības sistēmas integrēšanas nepieciešamību uzņēmumā un izstrādāt ieviešanas plānu. Pētījuma procesā bija izanalizētas vairākas integrēšanas iespējas. Rezultātā darba autore secināja, ka labāk ir izmantot integrācijas moduļus, jo tas ievērojami atvieglo un paātrina implementēšanas procesu. Kopējais bakalaura darba apjoms ir 60 lapaspuses. Darbā ir iekļautas 7 tabulas un 14 attēli.

Steady and oscillatory shear behaviour of semi-concentrated starch suspensions

2011

The viscoelastic moduli G’ and G” of aqueous suspensions with 40% (w/v) normal corn starch (NCS) and waxy corn starch (WCS) were determined by oscillation rheometry. The oscillatory shear flow experiments at heating from 30° to 75 °C and maintaining at this temperature showed changes from a behaviour predominant viscous (G”>>G’) to predominant elastic (G’>G”) for both starches at 60.5 °C for WCS, respectively 70,85 °C for NCS, WCS having higher values of G’ and G” as NCS. After the gelatinisation temperature was attired, NCS showed no significant changes, both moduli remaining relatively constant. Peaks of both moduli G’ and G” were obtained for WCS at its maintaining at 75oC, these changes…

MR 3020148 Reviewed McMullen, C.T. Braid groups and Hodge theory. Mathematische Annalen, vol. 355 (2013), pp.893–-946. (Reviewer Francesca Vetro) 20F…

2014

In this paper, the author studies the unitary representations of the braid group and the geometric structures on moduli space that arise via the Hodge theory of cyclic branched coverings of P^1. In particular, the author is interested in the classification of certain arithmetic subgroups of U(r, s) which envelop the image of the braid group. The author investigates their connections with complex reflection groups, Teichm\"{u}lller curves, ergodic theory and problems in surface topology.

Comparison of mechanical properties and composition of magnetron sputter and plasma enhanced atomic layer deposition aluminum nitride films

2018

A comparative study of mechanical properties and elemental and structural composition was made for aluminum nitride thin films deposited with reactive magnetron sputtering and plasma enhanced atomic layer deposition (PEALD). The sputtered films were deposited on Si (100), Mo (110), and Al (111) oriented substrates to study the effect of substrate texture on film properties. For the PEALD trimethylaluminum–ammonia films, the effects of process parameters, such as temperature, bias voltage, and plasma gas (ammonia versus N2/H2), on the AlN properties were studied. All the AlN films had a nominal thickness of 100 nm. Time-of-flight elastic recoil detection analysis showed the sputtered films t…