• 한국인터넷방송통신학회논문지
• /
• 제10권5호
• /
• pp.193-199
• /
• 2010

본 논문에서는 Ad Hoc 망의 동적인 연결 상태를 측정하는 도구로서 두 노드 사이의 최대 클러스터간 거리가 전파반경을 넘어서는 시간, 즉 경로 붕괴시간 $T_i$ 들의 합 $\sum_{i}T_i$를 측도로 사용할 것을 제안한다. 경로 붕괴시간 $T_i$는 모빌리티 모델로부터 노드들의 위치를 시간 샘플링한 후 이진 Clustering을 통해 최대 Cluster 거리를 시간의 함수로 구하고, 이로부터 전파반경을 넘어서는 시간구간을 찾아서 구한다. 본 논문에서 제안하는 측도는 개별 연결에 대한 측도로서 뿐만 아니라, 평균을 취함으로서 시스템 전체의 특성을 규정짓는 측도로서도 사용할 수 있다.

• 대한수학회보
• /
• 제55권3호
• /
• pp.871-879
• /
• 2018

The purpose of the present paper is to study on nearly $paraK{\ddot{a}}hler$ manifolds. Firstly, to investigate some properties of the Ricci tensor and the $Ricci^*$ tensor of nearly $paraK{\ddot{a}}hler$ manifolds. Secondly, to define a special metric connection with torsion on nearly $paraK{\ddot{a}}hler$ manifolds and present its some properties.

• 대한수학회보
• /
• 제51권6호
• /
• pp.1579-1589
• /
• 2014

We study the Dirac spectrum on compact Riemannian spin manifolds M equipped with a metric connection ${\nabla}$ with skew torsion $T{\in}{\Lambda}^3M$ in the situation where the tangent bundle splits under the holonomy of ${\nabla}$ and the torsion of ${\nabla}$ is of 'split' type. We prove an optimal lower bound for the first eigenvalue of the Dirac operator with torsion that generalizes Friedrich's classical Riemannian estimate.

• East Asian mathematical journal
• /
• 제30권3호
• /
• pp.371-383
• /
• 2014

We study the geometry of lightlike submanifolds of a semi-Riemannian manifold. The purpose of this paper is to prove two singular theorems for irrotational lightlike submanifolds M of a semi-Riemannian space form $\bar{M}(c)$ admitting a semi-symmetric non-metric connection such that the structure vector field of $\bar{M}(c)$ is tangent to M.

• 충청수학회지
• /
• 제32권3호
• /
• pp.281-293
• /
• 2019

In the present paper, we study quasi-concircular curvature tensor satisfying certain curvature conditions on a Lorentzian ${\beta}$-Kenmotsu manifold with respect to the semi-symmetric semi-metric connection.

• Structural Engineering and Mechanics
• /
• 제17권6호
• /
• pp.767-788
• /
• 2004

The classical 8-node isoparametric serendipity element uses parametric shape functions for both test and trial functions. Although this element performs well in general, it yields poor results under severe mesh distortions. The distortion sensitivity is caused by the lack of continuity and/or completeness of shape functions used for test and trial functions. A recent element using parametric and metric shape functions for constructing the test and trial functions exhibits distortion immunity. This paper discusses the choice of parametric or metric shape functions as the basis for test and/or trial functions, satisfaction of continuity and completeness requirements, and their connection to distortion sensitivity. Also, the performances of four types of elements, viz., parametric, metric, parametric-metric, and metric-parametric, are compared for distorted meshes, and their merits and demerits are discussed.

• 대한수학회논문집
• /
• 제30권1호
• /
• pp.35-43
• /
• 2015

We study two types of 1-lightlike submanifolds, so-called lightlike hypersurface and half lightlike submanifold, of an indefinite trans-Sasakian manifold $\bar{M}$ admitting non-metric ${\theta}$-connection. We prove that there exist no such two types of 1-lightlike submanifolds of an indefinite trans-Sasakian manifold $\bar{M}$ admitting non-metric ${\theta}$-connections.

• 한국수학교육학회지시리즈B:순수및응용수학
• /
• 제10권4호
• /
• pp.279-288
• /
• 2003

In the present paper, we treat a Finsler space with a special (${\alpha},\;{\beta}$)-metric $L({\alpha},\;{\beta})\;\;C_1{\alpha}＋C_2{\beta}+{\alpha}^2/{\beta}$ satisfying some conditions. We find a condition that a Finsler space with a special (${\alpha},\;{\beta}$)-metric be a Berwald space. Then it is shown that if a two-dimensional Finsler space with a special (${\alpha},\;{\beta}$)-metric is a Landsberg space, then it is a Berwald space.

• 호남수학학술지
• /
• 제39권1호
• /
• pp.115-126
• /
• 2017

In this paper, we aim to prove certain common fixed point theorems for a pair of weakly compatible mappings satisfying (CLRg) (or (E.A)) property in the bicomplex valued metric spaces. We also provide some examples which support the main results here.

• 충청수학회지
• /
• 제36권3호
• /
• pp.163-169
• /
• 2023

In this article, we consider a vectorial linear connection which is determined by three fixed vector fields. Classifying these vectorial connections, we obtain a new type of generalized statistical manifolds which allow non-zero torsion.