• Korean Journal of Crystallography
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• v.10 no.1
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• pp.1-8
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• 1999

Two conformational isomers of p-tert-butylcalix[4]arene hexanoate were prepared from the reaction of-p-tert-butylcalix[4]arene and hexanoly chloride in the presence of AlCl3 in CH2Cl2 and their structures were determined by NMR spectra and X-ray diffraction as a cone and a 1,3-alternate conformer, respectively. The crystal of cone conformer (C68H96O8·(CH3)2CO) is triclinic, P, a=15.066(1) , b=16.063(1) , c=16.365(1) , α=79.75(2)o, β=109.95(2)o, γ=80.32(0)o, V=3602.7(4) 3, Z=2. The intensity data were collected on Simens SMART diffractometer/CCD area detector. The structure was solved by direct method and refined by least-squares calculations to a final R value of 0.144 for 4638 observed reflections. The molecular conformation is distorted symmetric cone with the flattening A and D phenyl rings. The crystal of 1,3-alternate conformer (C68H96O8·2CHCl3) is orthorhombic, Pca21, a=34.586(5) , b=10.207(3) , c=20.394(4) , V=7199(3) 3, Z=4. The intensity data were collected on an Enraf-Noninus CAD-4 Diffractometer with a graphite monochromated Mo-K radiation. The structure was solved by direct method and refined by least-squares calculations to a final R value of 0.152 for 2241 observed reflections. The molecule has a pseudo mirror symmetric 1,3-alternate conformation.

• The korean journal of orthodontics
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• v.53 no.4
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• pp.219-231
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• 2023

Objective: This study aimed to clarify differences in the positions of cone-beam computed tomography (CBCT) landmarks according to different midsagittal planes (MSPs) in patients with skeletal Class III facial asymmetry. Methods: Pre-treatment CBCT data from 60 patients with skeletal Class III were used. The patients were classified into symmetric (menton deviations of < 2 mm) or asymmetric (menton deviations of > 4 mm) groups. Six MSPs were established based on previous studies, and three-dimensional analyses were performed for the planes in both the groups. The measurement outcomes were compared statistically. Results: A statistically significant interaction (p < 0.01) was observed between MSPs and facial asymmetry. No significant differences were observed among MSPs in the symmetric group. However, significant differences in linear measurements were identified among MSPs in the asymmetric group. Specifically, the upper facial MSP revealed both maxillary and mandibular transverse asymmetries. On the other hand, anterior nasal spine (ANS)-associated MSP could not identify maxillary asymmetry. Furthermore, the menton deviation was approximately 3 mm lower when estimated using the ANS-associated MSP than that using upper facial MSP. Conclusions: The choice of MSP can significantly affect treatment outcomes while diagnosing patients with asymmetry. Therefore, care should be taken when selecting MSP in clinical practice.

• Nonlinear Functional Analysis and Applications
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• v.26 no.5
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• pp.1105-1114
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• 2021

In this paper, we prove a fixed point theorem for G-contractive type non-self mapping in cone metric space endowed with a graph. Our result generalizes many results in the literature and provide a new pavement for solving nonlinear functional equations.

• Journal of applied mathematics & informatics
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• v.22 no.1_2
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• pp.295-306
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• 2006

In this paper, by using the Krasnoselskii fixed point theorem, we study the existence of 2m or 2m + 1 symmetric positive solutions of fourth-order two point boundary value problem y(4)(t) - f(t, y(t), y"(t))= 0, y(0) = y(1) = y'(0) = y"(1)=0.

• Journal of applied mathematics & informatics
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• v.27 no.5_6
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• pp.1109-1118
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• 2009

In this paper, we are concerned with the following four point boundary value problem with one-dimensional p-Laplacian, $\{({\phi}_p(x'(t)))'+h(t)f(t,x(t),|x'(t)|)=0$, 0< t<1, $x'(0)-{\delta}x(\xi)=0,\;x'(1)+{\delta}x(\eta)=0$, where $\phi_p$ (s) = |s|$^{p-2}$, p > $\delta$ > 0, 1 > $\eta$ > $\xi$ > 0, ${\xi}+{\eta}$ = 1. By using a fixed point theorem in a cone, we obtain the existence of at least three symmetric positive solutions. The interesting point is that the boundary condition is a new Sturm-Liouville-like boundary condition, which has rarely been treated up to now.

• The korean journal of orthodontics
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• v.43 no.5
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• pp.209-217
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• 2013

Objective: This study investigated whether temporomandibular joint (TMJ) condyle-fossa relationships are bilaterally symmetric in class III malocclusion patients with and without asymmetry and compared to those with normal occlusion. The hypothesis was a difference in condyle-fossa relationships exists in asymmetric patients. Methods: Group 1 comprised 40 Korean normal occlusion subjects. Groups 2 and 3 comprised patients diagnosed with skeletal class III malocclusion, who were grouped according to the presence of mandibular asymmetry: Group 2 included symmetric mandibles, while group 3 included asymmetric mandibles. Pretreatment three-dimensional cone-beam computed tomography (3D CBCT) images were obtained. Right- and left-sided TMJ spaces in groups 1 and 2 or deviated and non-deviated sides in group 3 were evaluated, and the axial condylar angle was compared. Results: The TMJ spaces demonstrated no significant bilateral differences in any group. Only group 3 had slightly narrower superior spaces (p < 0.001). The axial condylar angles between group 1 and 2 were not significant. However, group 3 showed a statistically significant bilateral difference (p < 0.001); toward the deviated side, the axial condylar angle was steeper. Conclusions: Even in the asymmetric group, the TMJ spaces were similar between deviated and non-deviated sides, indicating a bilateral condyle-fossa relationship in patients with asymmetry that may be as symmetrical as that in patients with symmetry. However, the axial condylar angle had bilateral differences only in asymmetric groups. The mean TMJ space value and the bilateral difference may be used for evaluating condyle-fossa relationships with CBCT.

• Journal of the Korean Geotechnical Society
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• v.35 no.2
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• pp.37-51
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• 2019

This study focuses on the numerical simulations of the cone penetration tests in a sand ground. The mechanical responses of sand were described using the modified Mohr Coulomb plasticity model based on the critical state soil mechanics. In the plasticity model, the dilatancy angle was not a constant, but a function of the distance to the critical state line from the current state of void ratio and mean effective stress. To simulate cone penetration tests numerically, this study relied on Lagrangian finite element method under the axisymmetric condition. To enable penetration of the cone penetrometer without tearing elements along the symmetric axis, the penetration guide concept was adopted in this study. The results of numerical simulations on the calibration chamber cone penetration tests had good agreement with the experimental results.

• 한국정보디스플레이학회:학술대회논문집
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• 2006.08a
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• pp.1132-1134
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• 2006

In this research, we examined the correlation between the polymer wall boundary condition and the dynamic/ memory behavior of the ferroelectric liquid crystal (FLC) molecules. It was shown that the polymer wall perpendicular to the rubbing direction induces asymmetric switching to the rubbing direction and induce smaller cone angle angle of LC. On the contrary, in the cell with polymer wall parallel to the rubbing direction, the FLC molecules are oriented in the rubbing direction and shows symmetric switching and has larger cone angle. Memory behavior of each cell has strong correlation with the dynamic state of the FLC molecules. Response time of each cell was also examined.

• Structural Engineering and Mechanics
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• v.58 no.6
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• pp.1001-1020
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• 2016

The study is to investigate the free vibration of antisymmetric angle-ply conical shells having non-uniform sinusoidal thickness variation. The arbitrarily varying thickness is considered in the axial direction of the shell. The vibrational behavior of shear deformable conical shells is analyzed for three different support conditions. The coupled differential equations in terms displacement and rotational functions are obtained. These displacement and rotational functions are invariantly approximated using cubic spline. A generalized eigenvalue problem is obtained and solved numerically for an eigenfrequency parameter and an associated eigenvector of spline coefficients. The vibration characteristic of the shells is examined for cone angle, aspect ratio, sinusoidal thickness variation, layer number, stacking sequence, and boundary conditions.

• Journal of applied mathematics & informatics
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• v.28 no.5_6
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• pp.1395-1408
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• 2010

In this paper, a pair of Wolfe type second-order nondifferentiable multiobjective symmetric dual program over arbitrary cones is formulated. Weak, strong and converse duality theorems are established under second-order (F, $\alpha$, $\rho$, d)-convexity assumptions. An illustration is given to show that second-order (F, $\alpha$, $\rho$, d)-convex functions are generalization of second-order F-convex functions. Several known results including many recent works are obtained as special cases.