• Title/Summary/Keyword: real existence

Search Result 418, Processing Time 0.026 seconds

Hopf Hypersurfaces in Complex Two-plane Grassmannians with Generalized Tanaka-Webster Reeb-parallel Structure Jacobi Operator

  • Kim, Byung Hak;Lee, Hyunjin;Pak, Eunmi
    • Kyungpook Mathematical Journal
    • /
    • v.59 no.3
    • /
    • pp.525-535
    • /
    • 2019
  • In relation to the generalized Tanaka-Webster connection, we consider a new notion of parallel structure Jacobi operator for real hypersurfaces in complex two-plane Grassmannians and prove the non-existence of real hypersurfaces in $G_2({\mathbb{C}}^{m+2})$ with generalized Tanaka-Webster parallel structure Jacobi operator.

SOME GENERALIZATION OF THE LANG'S EXISTENCE OF RATIONAL PLACE THEOREM

  • Cho, In-Ho;Lim, Jong-In
    • Bulletin of the Korean Mathematical Society
    • /
    • v.22 no.2
    • /
    • pp.83-85
    • /
    • 1985
  • Let K be a real function field over a real closed field F. Then there exists an F-place .phi.:K.rarw.F.cup.{.inf.}. This is Lang's Existence of Rational Place Theorem (6). There is an equivalent version of Lang's Theorem in (4). That is, if K is a function field over a field F, then, for any ordering P$_{0}$ on F which extends to K, there exists an F-place .phi.: K.rarw.F'.cup.{.inf.} where F' is a real closure of (F, P$_{0}$). In [2], Knebusch pointed out the converse of the version of Lang's Theorem is also true. By a valuation theoretic approach to Lang's Theorem, we have found out the following generalization of Lang and Knebusch's Theorem. Let K be an arbitrary extension field of a field F. then an ordering P$_{0}$ on F can be extended to an ordering P on K if there exists an F-place of K into some real closed field R containing F. Of course R$^{2}$.cap.F=P$_{0}$. The restriction K being a function field of F is vanished, though the codomain of the F-place is slightly varied. Therefore our theorem is a generalization of Lang and Knebusch's theorem.

  • PDF

Supervisor for Real-Time Nondeterministic Discrete Event Systems Under Bounded Time Constraints

  • Park, Seong-Jin;Cho, Kwang-Hyun;Lim, Jong-Tae
    • 제어로봇시스템학회:학술대회논문집
    • /
    • 2001.10a
    • /
    • pp.104.4-104
    • /
    • 2001
  • This paper addresses a supervisory control problem to meet bounded time constraints in real-time nondeterministic discrete event systems (DESs) represented as timed transition models. For a timed language specification representing a bounded time constraint, this paper introduces the notions of trace-controllability and time-controllability. Based on the notions, this paper presents the necessary and sufficient conditions for the existence of a supervisor for a real-time nondeterministic DES to achieve the specification.

  • PDF

RECURRENT STRUCTURE JACOBI OPERATOR OF REAL HYPERSURFACES IN COMPLEX HYPERBOLIC TWO-PLANE GRASSMANNIANS

  • JEONG, IMSOON;WOO, CHANGHWA
    • Journal of applied mathematics & informatics
    • /
    • v.39 no.3_4
    • /
    • pp.327-338
    • /
    • 2021
  • In this paper, we have introduced a new notion of recurrent structure Jacobi of real hypersurfaces in complex hyperbolic two-plane Grassmannians G*2(ℂm+2). Next, we show a non-existence property of real hypersurfaces in G*2(ℂm+2) satisfying such a curvature condition.

AN EXISTENCE OF THREE DIFFERENT NON-TRIVIAL SOLUTIONS FOR DISCRETE ANISOTROPIC EQUATIONS WITH TWO REAL PARAMETERS

  • Ahmed A.H., Alkhalidi;Haiffa Muhsan B., Alrikabi;Mujtaba Zuhair, Ali
    • Nonlinear Functional Analysis and Applications
    • /
    • v.27 no.4
    • /
    • pp.855-867
    • /
    • 2022
  • This study finds three different solutions (3-Sol's) for the fourth order nonlinear discrete anisotropic equations (DAE) with real parameter. We use the variational method(VM) and 𝜙p-Laplacian operator (𝜙p-LO) to prove the main results. In the following paper, we take the parameters λ, 𝜇 such that λ > 0 and 𝜇 ≥ 0 into consideration.

A Study on the Tendency of Realism in Modern Fashion -Focusing on Realism Formativeness expressed in the World of Honore Daumier리s Art- (현대패션에 표현된 리얼리즘 경향에 관한 연구 - 도미에(Honore Daumier리s)의 회화에 나타난 조형성을 중심으로 -)

  • Row Young;Im Nam-Young
    • Journal of the Korea Fashion and Costume Design Association
    • /
    • v.6 no.3
    • /
    • pp.185-199
    • /
    • 2004
  • This study is intended to examine Honore Daurnier's realism formativeness, review it in connection with socio-cultural conditions, analyze costume designs by a style of realism formativeness, in order to find the value. For the study, the procedure included the review of Daurnier's works and world, together with realism formativeness. Then, Daurnier's realism formativeness applied to costume designs were categorized and found the features of each style. Finally, it sought the implication of realism formativeness in costume designs. Honore Daumier, a realist of France in the 19th century, has been reputed that he pursues plain reality with a satire, uses all the conditions of humans as his object, and observes the vanity, desire, and foolishness of humans to represent his own expression techniques as cold as a stone. Realism formativeness is characterized by adherence to observing reality and engagement in reality, an effort to represent the world as it is as what we sense it without diluting or omitting it, nor any deception. The following terms can be used to describe the three styles of intentional recreation, satire on reality, and real existence; For intentional recreation in costume may be featured by the avant-garde, the pursuit of autonomy, reconstruction, rediscovery, recombination, reinterpretation, neutralized representation (reality + the abstract), transformation, distortion, shock, and unexpectedness, etc. For satire on reality in costume, satirical criticism and mockery in a coexistence of time and space, dualism due to the combination of the exterior and the interior, reality reflecting the actual reality, and irony are those words. Real existence in costume may be described with objectivity, ordinariness, correctness of representing a theme, impersonality excluding subjectivity, clearness, certainness, and preciseness, etc.

  • PDF

NONTRIVIAL PERIODIC SOLUTION FOR THE SUPERQUADRATIC PARABOLIC PROBLEM

  • Jung, Tacksun;Choi, Q-Heung
    • Korean Journal of Mathematics
    • /
    • v.17 no.1
    • /
    • pp.53-66
    • /
    • 2009
  • We show the existence of a nontrivial periodic solution for the superquadratic parabolic equation with Dirichlet boundary condition and periodic condition with a superquadratic nonlinear term at infinity which have continuous derivatives. We use the critical point theory on the real Hilbert space $L_2({\Omega}{\times}(0 2{\pi}))$. We also use the variational linking theorem which is a generalization of the mountain pass theorem.

  • PDF

Stability of Time Delay Systems Using Numerical Computation of Argument Principles

  • Suh, Young-Soo
    • International Journal of Control, Automation, and Systems
    • /
    • v.1 no.1
    • /
    • pp.127-133
    • /
    • 2003
  • This paper proposes a new numerical method to check the stability of a general class of time delay systems. The proposed method checks whether there are characteristic roots whose real values are nonnegative through two steps. Firstly, rectangular bounds of characteristic roots whose real values are nonnegative are computed. Secondly, the existence of roots inside the bounds are checked using the numerical computation of argument principles. An adaptive discretization is proposed for the numerical computation of argument principles.