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21.
Rafael Espínola Adrian Petru?el 《Journal of Mathematical Analysis and Applications》2005,309(2):420-432
The purpose of this note is to present some fixed point and data dependence theorems in complete gauge spaces and in hyperconvex metric spaces for the so-called Meir-Keeler multivalued operators and admissible multivalued aα-contractions. Our results extend and generalize several theorems of Espínola and Kirk [R. Espínola, W.A. Kirk, Set-valued contractions and fixed points, Nonlinear Anal. 54 (2003) 485-494] and Rus, Petru?el, and Sînt?m?rian [I.A. Rus, A. Petru?el, A. Sînt?m?rian, Data dependence of the fixed point set of some multivalued weakly Picard operators, Nonlinear Anal. 52 (2003) 1947-1959]. 相似文献
22.
Sanford S Miller Petru T Mocanu Maxwell O Reade 《Journal of Mathematical Analysis and Applications》1975,51(1):33-42
Suppose that f(z) = z + a2z2 + ··· + anzn + ··· is regular in the unit disc , and further let α ? 0 and k ? 2. If , then f(z) is said to belong to the class MV[α, k]. This class contains many of the special classes of regular and univalent functions. The authors determine the Hardy classes of which f(z), f′(z) and f″(z) belong and obtain growth estimates of an. 相似文献
23.
The effect of the molecular weight of the polystyrene on the properties of impact polystyrene obtained by mechanical mixing of polystyrene and rubber has been investigated. As the molecular weight of the polystyrene increases, the physicomechanical properties of the impact polystyrene improve and its rheological properties deteriorate. There is a definite correlation between the physicomechanical properties of the polystyrene and those of the impact polystyrene.Scientific-Research Institute of Synthetic Rubber, Kralupy-on-Vltava, Czechoslovakia. Translated from Mekhanika Polimerov, No. 3, pp. 545–546, May–June, 1971. 相似文献
24.
Petru Jebelean Gheorghe Moro?anu 《Journal of Mathematical Analysis and Applications》2006,313(2):738-753
This paper is concerned with the existence of solutions for the boundary value problem
25.
Haïm Brezis Petru Mironescu 《Annales de l'Institut Henri Poincaré (C) Analyse Non Linéaire》2018,35(5):1355-1376
We investigate the validity of the Gagliardo–Nirenberg type inequality
(1)
with . Here, are non negative numbers (not necessarily integers), , and we assume the standard relationsBy the seminal contributions of E. Gagliardo and L. Nirenberg, (1) holds when are integers. It turns out that (1) holds for “most” of values of , but not for all of them. We present an explicit condition on which allows to decide whether (1) holds or fails. 相似文献
26.
Haim?BrezisEmail author Petru?Mironescu Itai?Shafrir 《Calculus of Variations and Partial Differential Equations》2018,57(1):14
We introduce an equivalence relation on the space \(W^{1,1}(\Omega ;{\mathbb {S}}^1)\) which classifies maps according to their “topological singularities”. We establish sharp bounds for the distances (in the usual sense and in the Hausdorff sense) between the equivalence classes. Similar questions are examined for the space \(W^{1,p}(\Omega ;{\mathbb {S}}^1)\) when \(p>1\). 相似文献
27.
Petru Mironescu 《Comptes Rendus Mathematique》2010,348(9-10):513-515
Bourgain and Brezis established, for maps with zero average, the existence of a solution of (1) . Maz'ya proved that if, in addition, , then (1) can be solved in . Their arguments are quite different. We present an elementary property of fundamental solutions of the biharmonic operator in two dimensions. This property unifies, in two dimensions, the two approaches, and implies another (apparently unrelated) estimate of Maz'ya and Shaposhnikova. We discuss higher dimensional analogs of the above results. 相似文献
28.
Petru Mironescu 《Comptes Rendus Mathematique》2010,348(13-14):743-746
29.
Alberto Farina Petru Mironescu 《Calculus of Variations and Partial Differential Equations》2013,46(3-4):523-554
In a simply connected two dimensional domain Ω, we consider Ginzburg-Landau minimizers u with zero degree Dirichlet boundary condition ${g \in H^{1/2}(\partial \Omega; \mathbb{S}^1)}$ . We prove uniqueness of u whenever either the energy or the Ginzburg-Landau parameter are small. This generalizes a result of Ye and Zhou requiring smoothness of g. We also obtain uniqueness when Ω is multiply connected and the degrees of the vortexless minimizer u are prescribed on the components of the boundary, generalizing a result of Golovaty and Berlyand for annular domains. The proofs rely on new global estimates connecting the variation of |u| to the Ginzburg-Landau energy of u. These estimates replace the usual global pointwise estimates satisfied by ${\nabla u}$ when g is smooth, and apply to fairly general potentials. In a related direction, we establish new uniqueness results for critical points of the Ginzburg-Landau energy. 相似文献
30.
Carmen-Andreea Bădăluță Monica Ionita Viorica Nagavciuc Petruț-Ionel Bistricean 《Isotopes in environmental and health studies》2019,55(2):161-178
The region situated between the mountain area and the lowlands in NE Romania (East-Central Europe) is experiencing increased competition for water resources triggered by a growing population, intensification of agriculture, and industrial development. To better understand hydrological cycling processes in the region, a study was conducted using stable isotopes of water and atmospheric trajectory data to characterize regional precipitation and vapour sources derived from the Atlantic Ocean, Mediterranean and Black Seas, as well as recycled continental moisture, and to assess and partition these contributions to recharge of surface and groundwater. Atmospheric moisture in the lowlands is found to be predominantly delivered along easterly trajectories, while mountainous areas appear to be dominated by North Atlantic Ocean sources, with moisture transported along mid-latitude, westerly storm tracks. Large-scale circulation patterns affect moisture delivery, the North Atlantic Oscillation being particularly influential in winter and the East Atlantic pattern in summer. Winter precipitation is the main contributor to river discharge and aquifer recharge. As winter precipitation amounts are projected to decrease over the next decades, and water abstraction is expected to steadily increase, a general reduction in water availability is projected for the region. 相似文献