• On the generation of the cremona groupOn the generation of the cremona group

    1. Introduction Let Crk(n) = Bir(Pn k) denote the set of all birational maps of the projective space Pn k on a field k. It is clear that Crk(n) is a group under the composition of dominant rational maps; called the Cremona group of order n. It contains the group of automorphisms of Pn k, i.e. the group of projective linear transformations PGLk(...

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  • A second main theorem for entire curves in a projective variety whose derivatives vanish on inverse image of hypersurface targetsA second main theorem for entire curves in a projective variety whose derivatives vanish on inverse image of hypersurface targets

    1. Introduction During the last century, several Second Main Theorems have been established for linearly nondegenerate holomorphic curves in complex projective spaces intersecting (fixed or moving) hyperplanes, and we now have satisfactory knowledge about it. Motivated by a paper of Corvaja-Zannier [1] in Diophantine approximation, in 2004 Ru ...

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  • State-feedback control of discrete-time stochastic linear systems with markovian switchingState-feedback control of discrete-time stochastic linear systems with markovian switching

    Abstract. This paper is concerned with the stabilization problem via state-feedback control of discrete-time jumping systems with stochastic multiplicative noises. The jumping process of the system is driven by a discrete-time Markov chain with finite states and partially known transition probabilities. Sufficient conditions are established in ...

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  • Thực trạng dạy và học môn toán cao cấp cho các nhà kinh tế trong trường Đại học Kinh tế Quốc dânThực trạng dạy và học môn toán cao cấp cho các nhà kinh tế trong trường Đại học Kinh tế Quốc dân

    Tóm tắt. Bài báo trình bày nghiên cứu, phân tích thực trạng của việc dạy và học môn Toán cao cấp cho các nhà kinh tế (Toán cao cấp CCNKT) trong Trường Đại học Kinh tế Quốc dân, phân tích, so sánh nội dung chương trình môn Toán cao cấp CCNKT trong trường Đại học Kinh tế Quốc dân với nội dung chương trình môn Toán cao cấp ở một số trường trên thế ...

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  • Representation of some special functions on transcendence basisRepresentation of some special functions on transcendence basis

    2 Quasi‑shuffle algebra with the defor‑ mation q Let’s denote Y := {yk| k ∈ N+} an alphabet totally ordered by y1  y2  · · · . A word is a finite sequence of letters and Y ∗ denotes the set of all words includ‑ ing the empty word, denoted by 1Y ∗. This set is a free monoid2 and 1Y ∗ is a neutral element. We call each linear combination, ov...

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  • Cosine transform on time scalesCosine transform on time scales

    4. Application on solving linear difference equation In this section we consider the difference enquations of the first kind as well as the second kind. First, based on Wiener-Levy theorem [10], we have the proposition. Proposition 4.1 (Wiener-Levy’s type theorem). If f˜ is a transform Tc of function f belonging to L1(Th), φ(u) is an analytic f...

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  • Fibers of rational maps and rees algebras of their base idealsFibers of rational maps and rees algebras of their base ideals

    Besides the computation of implicit representations of parameterizations, in geometric modeling it is of vital importance to have a detailed knowledge of the geometry of the object and of the parametric representation one is working with. The question of how many times is the same point being painted (i.e., corresponds to distinct values of ...

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  • Structural characteritics of iron oxide nanoparticles synthesized by co-precipitation method in different conditionsStructural characteritics of iron oxide nanoparticles synthesized by co-precipitation method in different conditions

    Abstract. This study aimed to investigate the structural characteristics of iron oxide nanoparticles (IONPs) prepared in different conditions. IONPs were synthesized as aqueous magnetic fluids by co-precipitation of ferrous and ferric salts, then analyzed by transmission electron microscopy (TEM), X-ray diffraction (XRD), and Raman scattering sp...

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  • Phase diagram of colloidal systems: A comparison of standard monte carlo simulations and virtual-Move monte carlo simulationsPhase diagram of colloidal systems: A comparison of standard monte carlo simulations and virtual-Move monte carlo simulations

    Abstract. In this work, we investigate the phase diagram of a three-dimensional Lennard-Jones (LJ) and square-well (SQW) system by means of both standard Monte Carlo simulation (SPMC) and “virtual-move” Monte Carlo simulations (VMMC). We find that the phase diagrams obtained by both SPMC and VMMC are very similar. However, there exist a few sig...

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  • Study on nonlinear deformation of binary interstitial alloy AB with BCC structure under pressureStudy on nonlinear deformation of binary interstitial alloy AB with BCC structure under pressure

    1. Introduction When the object is deformed, its properties change, especially its mechanical properties. There are two types of deformation: elastic deformation and nonlinear deformation. When the load is too large, the object will be deformed nonlinearly and the material itself will have a residual deformation. Nonlinear deformation causes ma...

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