• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.1102-1107
• /
• 1992

Existing CAD systems do nto provide the advanced function for systematic checking of design and drafting errors in mechanical drawings. This paper describes a method for sytematic checking of global parts in mechanical drawings. The checking items are deficiency and redundancy of dimensions, input-errors in dimension figures and symbols, etc. Checking for deficiency and redundancy of global dimensions has been performed applying Graph Theory. This system has been applied to several examples and we have confirmed the feasibility of this checing method.

• 제어로봇시스템학회:학술대회논문집
• /
• 1992.10a
• /
• pp.513-518
• /
• 1992

We are now doing research for the drawing check of local parts in mechanical drawing made by a CAD system. It needs the recognition of drawing elements with respect to the local parts. Because, we usually abbreviate the dimensioning in the mutually related drawing elements. This paper is concerned with a computer aided supporting system to the dimension check and recognition of local parts in mechanical drawings. This sytem has been applied to some examples and we have confirmed the feasibility of this checking method.

• Korean Journal of Mathematics
• /
• v.12 no.1
• /
• pp.23-32
• /
• 2004

Let (B, $m_B$, ${\kappa}$) be a maximal commutative ${\kappa}$-subalgebra of a matrix algebra $M_n(\kappa)$. We will construct a maximal commutative ${\kappa}$-subalgebra (R, $m$, ${\kappa}$) of $M_n+3(\kappa)$ from the algebra B such that the algebra R has dimension greater than the dimension of B by 3. Moreover, we will show a $C_i$-construction doesn't imply a $C^3_2$-construction for $i=1,2$.

• Journal of the Korean Mathematical Society
• /
• v.53 no.5
• /
• pp.1167-1182
• /
• 2016

Let M be an R-module, where R is a commutative ring with identity 1 and let G(V,E) be a graph. In this paper, we study the graphs associated with modules over commutative rings. We associate three simple graphs $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$ to M called full annihilating, semi-annihilating and star-annihilating graph. When M is finite over R, we investigate metric dimensions in $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$. We show that M over R is finite if and only if the metric dimension of the graph $ann_f({\Gamma}(M_R))$ is finite. We further show that the graphs $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$ are empty if and only if M is a prime-multiplication-like R-module. We investigate the case when M is a free R-module, where R is an integral domain and show that the graphs $ann_f({\Gamma}(M_R))$, $ann_s({\Gamma}(M_R))$ and $ann_t({\Gamma}(M_R))$ are empty if and only if $$M{\sim_=}R$$. Finally, we characterize all the non-simple weakly virtually divisible modules M for which Ann(M) is a prime ideal and Soc(M) = 0.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
• /
• v.48 no.1
• /
• pp.33-40
• /
• 2022

Objectives: Prolotherapy is a method that has gained popularity in recent years and has been reported to have positive short-term and long-term clinical results in maxillofacial surgery, especially temporomandibular joint (TMJ) hypermobility. This study aimed to evaluate the changes in the trabecular structure of mandibular condyles in patients who underwent prolotherapy due to TMJ hypermobility using the fractal analysis method. Materials and Methods: Forty-five patients who received dextrose prolotherapy at a concentration of 20% and fifteen control patients were included in the study. All patients had panoramic radiographs just before (T0) and six months after treatment (T1). The patients who received treatment were divided into three groups according to the number of prolotherapy injections. The regions of interest were selected from bone areas close to the articular surfaces of the condyles. The fractal dimension (FD) values were calculated. Results: The main effect of time on the FD value was significant [F (1, 56)=86.176, P<0.001]. This effect was qualified by a significant time×group interaction effect [F (3, 56)=9.023, P<0.001]. The decreases in FD values in all treatment groups between T0 and T1 times were significant (P=0.004). However, changes in FD values were not significant in the control group (P=0.728). Conclusion: Dextrose prolotherapy without the effect of the number of injections caused a decrease in FD values in the mandibular condyles over time.

• Journal of the Korean Mathematical Society
• /
• v.52 no.2
• /
• pp.269-331
• /
• 2015

For a fixed positive integer g, we let $\mathcal{P}_g=\{Y{\in}\mathbb{R}^{(g,g)}{\mid}Y=^tY&gt;0\}$ be the open convex cone in the Euclidean space $\mathbb{R}^{g(g+1)/2}$. Then the general linear group GL(g, $\mathbb{R}$) acts naturally on $\mathcal{P}_g$ by $A{\star}Y=AY^tA(A{\in}GL(g,\mathbb{R}),\;Y{\in}\mathcal{P}_g)$. We introduce a notion of polarized real tori. We show that the open cone $\mathcal{P}_g$ parametrizes principally polarized real tori of dimension g and that the Minkowski modular space 𝔗g = $GL(g,\mathbb{Z}){\backslash}\mathcal{P}_g$ may be regarded as a moduli space of principally polarized real tori of dimension g. We also study smooth line bundles on a polarized real torus by relating them to holomorphic line bundles on its associated polarized real abelian variety.

• Journal of the Korean Mathematical Society
• /
• v.60 no.1
• /
• pp.115-141
• /
• 2023

We study a class of left-invariant pseudo-Riemannian Sasaki metrics on solvable Lie groups, which can be characterized by the property that the zero level set of the moment map relative to the action of some one-parameter subgroup {exp tX} is a normal nilpotent subgroup commuting with {exp tX}, and X is not lightlike. We characterize this geometry in terms of the Sasaki reduction and its pseudo-Kähler quotient under the action generated by the Reeb vector field. We classify pseudo-Riemannian Sasaki solvmanifolds of this type in dimension 5 and those of dimension 7 whose Kähler reduction in the above sense is abelian.

• Journal of the Korean Mathematical Society
• /
• v.31 no.3
• /
• pp.339-352
• /
• 1994

A sumbanifold M of a quaternionic Kaehlerian manifold $\tilde{M}^m$ of real dimension 4m is called a generic submanifold if the normal space N(M) of M is always mapped into the tangent space T(M) under the action of the quaternionic Kaehlerian structure tensors of the ambient manifold at the same time.The purpose of the present paper is to study generic submanifold of quaternionic Kaehlerian manifold of constant Q-sectional curvature with nonvanishing parallel mean curvature vector. In section 1, we state general formulas on generic submanifolds of a quaternionic Kaehlerian manifold of constant Q-sectional curvature. Section 2 is devoted to the study generic submanifolds with nonvanishing parallel mean curvature vector and compute the restricted Laplacian for the second fundamental form in the direction of the mean curvature vector. As applications of those results, in section 3, we prove our main theorems. In this paper, the dimension of a manifold will always indicate its real dimension.

• Korean Journal of Mathematics
• /
• v.7 no.1
• /
• pp.1-5
• /
• 1999

We will find sufficient conditions for a Mari domain to be a Krull domain.

• Journal of the Korea Society of Computer and Information
• /
• v.16 no.1
• /
• pp.201-210
• /
• 2011

Each area of society has changed because of the development of information technology. Especially, the advent of NCW based on the technology of network has become a new paradigm for executing warfare. Effectiveness of NCW can be maximized by building the C4I system which is a core system of NCW. However, if we don't consider the influence in term of human dimension, we can't expect the effect of C4I system, since the key factor in C4I is human. In this paper, we propose an algorithm for evaluating Combat Power Effectiveness by considering the Influence of Human Factors that wasn't reflected in the past. Based on experimental validation our algorithm is more substantial than baseline algorithms. In addition, we proved that the Influence of Human Factors(e.g. collaboration) is the most important in battlefield. Therefore, proposed algorithm can be used for enhancing not only mission effectiveness in terms of military field but also work performance by effective Human Resource Management in terms of an enterprise.