All issues
Volume 48 (1996)
- Issue 4 Pages 471-
- Issue 3 Pages 317-
- Issue 2 Pages 165-
- Issue 1 Pages 1-
Predecessor
Volume 48, Issue 3
Displaying 1-9 of 9 articles from this issue
- |<
- <
- 1
- >
- >|
-
FUMIHARU KATO1996 Volume 48 Issue 3 Pages 317-354
Published: September 01, 1996
Released on J-STAGE: May 22, 2009
JOURNAL FREE ACCESSThis paper lays a foundation for log smooth deformation theory. We study the infinitesimal liftings of log smooth morphisms and show that the log smooth deformation functor has a representable hull. This deformation theory gives, for example, the following two types of deformations: (1) relative deformations of a certain kind of a pair of an algebraic variety and a divisor on it, and (2) global smoothings of normal crossing varieties. The former is a generalization of the relative deformation theory introduced by Makio and others, and the latter coincides with the logarithmic deformation theory introduced by Kawamata and Namikawa.View full abstractDownload PDF (1557K) -
GEZA MAKAY1996 Volume 48 Issue 3 Pages 355-362
Published: September 01, 1996
Released on J-STAGE: May 22, 2009
JOURNAL FREE ACCESSWe consider periodic, infinite delay differential equations. We investigate dissipativeness for these equations. Massat proved that dissipative, periodic, infinite delay equations have a periodic solution. For our purpose we need a weaker dissipativeness, so we prove Massat's theorem from this weak dissipativeness in an elementary way. Then we extend a theorem of Pliss giving a necessary and sufficient condition for this weak dissipativeness. We also present a theorem using Liapunov functionals to show the weak dissipativeness and hence the existence of a periodic solution.View full abstractDownload PDF (379K) -
GOTTFRIED BARTHEL, JEAN-PAUL BRASSELET, KARL-HEINZ FIESELER1996 Volume 48 Issue 3 Pages 363-390
Published: September 01, 1996
Released on J-STAGE: May 22, 2009
JOURNAL FREE ACCESSFor a complex toric variety, we compare the natural inclusion of the group of classes of invariant Cartier divisors into that of Weil divisors on the one hand, and the Poincaré duality homomorphism between the second integral cohomology and the integral homology (with closed supports) in complementary degree on the other. If the variety has finite fundamental group, we prove that the natural "Chern class homomorphism" from the group of classes of invariant Cartier divisors to cohomology and the "homology class map" from the group of classes of invariant Weil divisors to homology are both isomorphisms, thus identifying the inclusion of these divisor class groups with the Poincaré duality homomorphism. Using suitable Kunneth formulae, that yields a result valid in the general case.
These groups of classes of invariant divisors-and hence the corresponding (co-) homology groups-have explicit descriptions in terms of combinatorial-geometric data of the fan that defines the toric variety. As an application, we use these to discuss problems of invariance of Betti numbers for toric varieties.View full abstractDownload PDF (1332K) -
Huaxing XIA, Jianhong WU1996 Volume 48 Issue 3 Pages 391-416
Published: 1996
Released on J-STAGE: March 18, 2014
JOURNAL FREE ACCESSWe consider the dynamics of a logistic neutral delay system which is continuous in time and discrete in space. Such a system models the growth of a single-species population distributed over a ring of identical patches and it allows for population dispersing from one patch to its nearest neighbors. We shall show that (i) in the case of instantaneous dispersion feedback, the dispersal in the local growth rate and the neutral term have a stablizing effect on the population dynamics; (ii) increasing the delay in the growth phase changes the stability of a positive equilibrium and leads to a Hopf bifurcation of synchronous or phase-locked oscillations if the dispersion is small; (iii) the neutral term may bring about several global branches of phase-locked oscillations which would not occur in the absence of a neutral term, .and hence the neutral term in this situation has a destablizing influence.View full abstractDownload PDF (1777K) -
JIE DU1996 Volume 48 Issue 3 Pages 417-427
Published: September 01, 1996
Released on J-STAGE: May 22, 2009
JOURNAL FREE ACCESSWe decompose the canonical bases for q-Schur algebras and the modified quantized enveloping algebras of type A into two-sided cells in terms of some combinatorics on certain sets of matrices.View full abstractDownload PDF (455K) -
HITOSHI TANAKA1996 Volume 48 Issue 3 Pages 429-435
Published: September 01, 1996
Released on J-STAGE: May 22, 2009
JOURNAL FREE ACCESSIn this paper we shall give an elementary proof of a norm estimate given by Igari for the Kakeya maximal operator restricted to functions of product type. Our proof also gives an improvement of the result.View full abstractDownload PDF (201K) -
Dedicated to Professor Satoru Igari on his sixtieth birthdayYONG DING, SHANZHEN LU1996 Volume 48 Issue 3 Pages 437-449
Published: September 01, 1996
Released on J-STAGE: May 22, 2009
JOURNAL FREE ACCESSIn this paper the authors study the weighted Lp-boundedness for higher order commutators of a class of oscillatory singular integrals with rough kernel. The main result in this paper gives a necessary and sufficient condition so that this higher order commutator is bounded on the weighted Lp space with certain weight.View full abstractDownload PDF (365K) -
Robert LATERVEER1996 Volume 48 Issue 3 Pages 451-458
Published: 1996
Released on J-STAGE: March 18, 2014
JOURNAL FREE ACCESSA version of Fujita's conjectures is proven for Q-Gorenstein toric varieties.View full abstractDownload PDF (517K) -
RAJENDRA VASANT GURJAR, MASAYOSHI MIYANISHI1996 Volume 48 Issue 3 Pages 459-469
Published: September 01, 1996
Released on J-STAGE: May 22, 2009
JOURNAL FREE ACCESSConcerning the topologically contractible curves embedded in the affine plane defined over the complex numbers we shall present new conceptual proofs to the theorem of Abhyankar-Moh and the theorem of Lin-Zaidenberg which are based on the structure theorems of non-complete algebraic surfaces.View full abstractDownload PDF (561K)
- |<
- <
- 1
- >
- >|