• 대한수학회논문집
• /
• 제38권1호
• /
• pp.243-256
• /
• 2023

We deal with a type of inverse pseudo-orbit tracing property with respect to the class of continuous methods, as suggested and studied by Pilyugin [54]. In this paper, we consider a continuous method induced through the diffeomorphism of a compact smooth manifold, and using the concept, we proved the following: (i) If a diffeomorphism f of a compact smooth manifold M has the robustly pointwise inverse pseudoorbit tracing property, f is structurally stable. (ii) For a C1 generic diffeomorphism f of a compact smooth manifold M, if f has the pointwise inverse pseudo-orbit tracing property, f is structurally stable. (iii) If a diffeomorphism f has the robustly pointwise inverse pseudo-orbit tracing property around a transitive set Λ, then Λ is hyperbolic for f. Finally, (iv) for C¹ generically, if a diffeomorphism f has the pointwise inverse pseudo-orbit tracing property around a locally maximal transitive set Λ, then Λ is hyperbolic for f. In addition, we investigate cases of volume preserving diffeomorphisms.

• Kyungpook Mathematical Journal
• /
• 제61권4호
• /
• pp.737-744
• /
• 2021

In this paper, among other things, we show that under special hypotheses every [pseudo] (n + 1)-Jordan homomorphism is a [pseudo] n-Jordan homomorphism and vice versa.

• 대한한의학방제학회지
• /
• 제24권1호
• /
• pp.31-43
• /
• 2016

Objectives Based on related literature, cold and heat, deficiency and excess, true and false, and actually used formulas, paradoxical treatments presented in the 『Plain Questions of Inner Canon of Yellow Emperor』 including ‘treating pseudo-heat symptoms and real cold syndrome with cold herbs, treating pseudo-heat symptoms and real cold syndrome with cold herbs’ were analyzed.Methods Out of literature, paradoxical treatment related classics and papers were investigated and analyzed. Among diseases and syndromes, real cold syndrome with pseudo-heat symptoms, real heat syndrome with pseudo-cold symptoms, real deficiency syndrome with pseudo-excess symptoms, and real excess syndrome with pseudo-deficiency symptoms were reviewed. Among formulas, typical examples of the above mentioned paradoxical treatments were used as examples to analyze paradoxical treatments.Results Treating pseudo-heat symptoms and real cold syndrome with cold herbs is a method that uses herbs with cool and cold nature to treat real cold syndrome with pseudo-heat symptoms and Tongmaeksayeokgajeodamjeuptang is suitable for this method. Treating pseudo-cold symptoms and real heat syndrome with hot herbs is a method that uses herbs with warm and hot nature to treat real heat syndrome with pseudo-cold symptoms and Baekhogainsamtang is suitable for this method.Conclusions Based on the related literature, cold and heat, deficiency and excess, true and false, and actually used formulas examined as mentioned above, the paradoxical treatments presented in the 『Plain Questions of Inner Canon of Yellow Emperor』 are thought to be reasonable paradoxical treatments that fit the diseases and syndromes that actually appeared in our bodies.

• 대한수학회논문집
• /
• 제35권4호
• /
• pp.1095-1106
• /
• 2020

The purpose of this paper is to introduce a new class of rings that is closely related to the class of pseudo-Krull domains. Let 𝓗 = {R | R is a commutative ring and Nil(R) is a divided prime ideal of R}. Let R ∈ 𝓗 be a ring with total quotient ring T(R) and define 𝜙 : T(R) → R_Nil(R) by ${\phi}({\frac{a}{b}})={\frac{a}{b}}$ for any a ∈ R and any regular element b of R. Then 𝜙 is a ring homomorphism from T(R) into R_Nil(R) and 𝜙 restricted to R is also a ring homomorphism from R into R_Nil(R) given by ${\phi}(x)={\frac{x}{1}}$ for every x ∈ R. We say that R is a 𝜙-pseudo-Krull ring if 𝜙(R) = ∩ R_i, where each R_i is a nonnil-Noetherian 𝜙-pseudo valuation overring of 𝜙(R) and for every non-nilpotent element x ∈ R, 𝜙(x) is a unit in all but finitely many R_i. We show that the theories of 𝜙-pseudo Krull rings resemble those of pseudo-Krull domains.

• 대한전자공학회논문지
• /
• 제17권3호
• /
• pp.20-25
• /
• 1980

Singular value decomposition을 통한 pseudo-inverse를 단층영상 재구성에 이용하였다. 본 논문에서는 SVD pseudo-inverse를 이용한 truncated inverse filter와 Scalar Wiener filter에 대하여 검토하고 각각에 대하여 통계적 측면에서의 최적화가 연구되었다. 이러한 방법은 신호와 잡음문에 trade-off를 기함으로써 재구성 문제에 항상 뒤따르는 ill-conditioning 현상을 극복할 수 있다. 본 논문을 통하여 구성된 filter의 성능을 확인하기 위하여 컴퓨터를 이용한 simulation이 이루어졌으며 그 결과 재구성된 협상은 만족할 만 하였다.

• 대한수학회보
• /
• 제49권2호
• /
• pp.353-358
• /
• 2012

In this paper, we focus on pseudo-Riemannian associative fermionic Novikov algebras. We prove that the underlying Lie algebras of pseudo-Riemannian associative fermionic Novikov algebras are 2-step nilpotent and that pseudo-Riemannian associative fermionic Novikov algebras are 3-step nilpotent. Moreover, we construct a pseudo-Riemannian associative fermionic Novikov algebra in dimension 14, which is not a Novikov algebra. It implies that the inverse proposition of Corollary 2 in the paper "Pseudo-Riemannian Novikov algebras" [J. Phys. A: Math. Theor. 41 (2008), 315207] does not hold.

• 한국조경학회지
• /
• 제26권2호
• /
• pp.28-37
• /
• 1998

The purpose of this study was to develop a model of plant management based on Robinia pseudo-acacia forests structure in Bucheon city, Korea. For 38 plots were established in Robinia pseudo-acacia forest of Bucheon city. As a result, Robinia pseudo-acacia community was expected to the proceeded to Quercus spp. community. In addition, the diversity of Robinia pseudo-acacia-Quercus spp. community was analyzed higher than Robinia pseudo-acacia community. Based on the result of forest structure analysis, Quercus spp. community was selected as the goal stage of plant management for Bucheon forests and 22 species that were selected by the importance value analysis, classification and ordination analysis and the correlation analysis were chosen as the ecological approprite species. This study also suggested density control guide line for sucession promotion, which individuals numbers of Robinia pseudo-acacia might be reduced from 50 individuals to 23 individuals by selective cutting in order to keep 65% of total basal area.

• 대한수학회지
• /
• 제48권1호
• /
• pp.1-12
• /
• 2011

The purpose of this paper is to study pseudo-Riemannian algebras, which are algebras with pseudo-Riemannian non-degenerate symmetric bilinear forms. We nd that pseudo-Riemannian algebras whose left centers are isotropic play a curial role and show that the decomposition of pseudo-Riemannian algebras whose left centers are isotropic into indecomposable non-degenerate ideals is unique up to a special automorphism. Furthermore, if the left center equals the center, the orthogonal decomposition of any pseudo-Riemannian algebra into indecomposable non-degenerate ideals is unique up to an isometry.

• 대한수학회보
• /
• 제58권4호
• /
• pp.897-908
• /
• 2021

In this paper, we introduce the notion of pseudo 2-prime ideals in commutative rings. Let R be a commutative ring with a nonzero identity. A proper ideal P of R is said to be a pseudo 2-prime ideal if whenever xy ∈ P for some x, y ∈ R, then x²ⁿ ∈ Pⁿ or y²ⁿ ∈ Pⁿ for some n ∈ ℕ. Various examples and properties of pseudo 2-prime ideals are given. We also characterize pseudo 2-prime ideals of PID's and von Neumann regular rings. Finally, we use pseudo 2-prime ideals to characterize almost valuation domains (AV-domains).

• 대한수학회보
• /
• 제61권3호
• /
• pp.867-873
• /
• 2024

A pseudo-Riemannian solvmanifold is a solvable Lie group endowed with a left invariant pseudo-Riemannian metric. In this short note, we investigate the nilpotency of the Ricci operator of pseudo-Riemannian solvmanifolds. We focus on a special class of solvable Lie groups whose Lie algebras can be expressed as a one-dimensional extension of a nilpotent Lie algebra ℝD⋉n, where D is a derivation of n whose restriction to the center of n has at least one real eigenvalue. The main result asserts that every solvable Lie group belonging to this special class admits a left invariant pseudo-Riemannian metric with nilpotent Ricci operator. As an application, we obtain a complete classification of three-dimensional solvable Lie groups which admit a left invariant pseudo-Riemannian metric with nilpotent Ricci operator.