• Aerospace Engineering and Technology
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• v.5 no.2
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• pp.159-165
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• 2006

In this study, structural analysis is executed about cone structure of KSL V-1 2nd stage KMS(kick motor support structure) which is designed for support the load developed from 2nd stage kick motor. KMS is consisted of cone structure and truss structure which is designed for supporting load developed from 2nd stage payload. Applied loads to cone structure are tension load by inertia developed from kick motor and compression load developed from kick motor. Also, shear and bending load are developed according to flight condition. In this study, structural analysis of cone structure is executed under several load condition which may be applied to cone structure. Also, structural analysis with two finite element model is performed according to pressure vent scheme. In result of structural analysis, critical load condition is equivalent tension load with cut-out.

• Journal of the Korean Geotechnical Society
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• v.24 no.12
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• pp.53-63
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• 2008

In this study, the cone tip resistances of cemented sand are measured by performing a series of miniature cone penetration tests in large calibration chamber, and the relations with constrained modulus, unconfined compressive strength, and shear strength of cemented sand are suggested. Experimental results show that both the cone tip resistance and constrained modulus of sand increase with increasing cementation effect as well as relative density and confining stress. However, it is observed that the relative density and confining stress have more significant influence on cone tip resistance than constrained modulus of cemented sand. Since the cone penetration into the ground induces the damage of cementation, the cone tip resistance can't properly reflect the cementation effect of sand. An analysis based on the constrained modulus shows that the measured cone tip resistance underestimates the deformation modulus of cemented sand by about $70{\sim}85%$. In addition, this study establishes various relationships among the above soil properties from the regression analysis.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.179-188
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• 2006

In this study, R/S analysis which was proposed by Mandelbrot & Wallis(1969) was applied to evaluate the presence of the fractal property in the cone tip resistance of in-situ CPT data. Hurst exponents(H) were evaluated in the range of $0.660\sim0.990$ and the average was 0.875. It was confirmed that a cone tip resistance data had the characteristic of fractals and it was expected that cone tip resistance data sets are well approximated by a fBm process with an Hurst exponent near 0.875. It was also observed that the boundary between layers were obviously identified as a result of R/S analysis and it will be usage in practices.

• Korean Journal of Plant Resources
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• v.26 no.1
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• pp.1-8
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• 2013

This study was conducted to examine the relationship between cone abundance and cone/seed characteristics to improve seed quality and seed orchard management of Pinus koraiensis. The data was collected from P. koraiensis seed orchards at Chungju in 2007. That year was a rich year of cone harvest and the average number of cone per tree was 2.5 times much than that of normal year. We collected the cones from all trees in the sample plot of the seed orchard and investigated morphological characters such as cone length, cone width and cone weight. According to cone abundance per tree, the samples were divided into eight classes and analysed by cone analysis method. There is a decreasing tendency of number of fertile scale, seed potential, percent of filled seeds, seed weight per cone and seed efficiency, when the cone number per tree is increased. Additionally, the implications of the results to seed orchards management of P. koraiensis were discussed.

• Korean Journal of Plant Resources
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• v.25 no.4
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• pp.401-406
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• 2012

This study was conducted to investigate the effect of cone protective net and the variation of cone and seed characteristics of a unique and rare dwarf stone pine (Pinus pumila Regel) population in Mt. Seorak which is in the southern peripheral of South Korea. Iron protective net (50 mesh, 25 ${\times}$ 25 cm) was effective in reducing birds and rodents damage to conelet, thereby it was possible to safely collect seed genetic resources. Early July was observed to be the most appropriate season to cover conelet with Iron protective net. P. pumila have ovoid-triangle shaped, wingless seeds and indehiscent cones, seeds dissemination is mainly by the hoarding behavior of nutcrackers and rodents. Statistical analysis showed that there were significant differences among individuals within population, and the mean characteristics of the species were 35.3 mm, 25.6 mm, 1.38, 6.6 g and 39.3 ea in the cone length, cone width, cone index, cone weight and in number of seeds per cone, respectively. Coefficients of variations in seed weight and number of seeds per cone were relatively high (21.7%, 21.5%, respectively) compared to other traits. Based on the correlation analysis between cone characteristics and seed characteristics, the length of cone and seed showed a significant positive correlation with the seed size and the seed weight, but the width and thickness of seed showed a negative correlation with the number of seeds per cone.

• Nonlinear Functional Analysis and Applications
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• v.26 no.4
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• pp.649-662
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• 2021

Recently the author studied a one-parameter family of divergences and considered the related median minimization problem of finite points over these divergences in general symmetric cones. In this article, to utilize the results practically, we deal with a special symmetric cone called second order cone, which is important in optimization fields. To be more specific, concrete computations of divergences with its gradients and the unique minimizer of the median minimization problem of two points are provided skillfully.

• 한국전산유체공학회:학술대회논문집
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• 2007.10a
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• pp.177-180
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• 2007

A three dimensional numerical analysis has been made for the cone disk control valve and the flat disk control valve. The simulation of the incompressible flow in the each control vale are performed by using the commercial code. Six flow cases of each control valve are investigated.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.26 no.12
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• pp.1050-1057
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• 2015

This paper presents the characteristics of broadband double-cone antennas. The antenna is used to measure electromagnetic fields(2~5 GHz) radiated from a primary or a secondary electrode of a pole-transformer when partial discharge occurs inside the pole-transformer. The theoretical analysis is conducted using commercial software based on a finite difference time domain(FDTD) method. The parameters are a radius, and a height of the broadband double-cone antennas, and the number of posts on a ground plane. This paper examines influences of structural parameters of the broadband double-cone antennas on return loss. The results show that a condition for an optimum structure of broadband double-cone antennas exists. It also shows that the broadband double-cone antennas have radiation patterns similar to those of a dipole antenna. Therefore the broadband double-cone antennas are appropriate for the measurement of radiated electromagnetic fields from the pole-transformer. To verify the theoretical analysis, computed results are compared to experimental results.

• Journal of the Korean Society of Radiology
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• v.7 no.4
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• pp.301-305
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• 2013

This thesis intends to analyze tooth distortion by mandibular arch form by reproducing existing panorama image and reconstructed panorama image of Cone Beam CT data with the three-dimensional computer program. The diameter of tooth measured in Cone Beam CT's cross-section image and reconstructed panorama was synchronized without any big change from incisors to posteriors. But, panorama showed serious distortion as going to posteriors after showing a little distortion in incisors. The panorama reconstructed for patients' individual arch showed reduced distortion than panoramas used generally. In addition, panorama showed serious distortion from incisors to posteriors and it means that distortion is reduced in reconstructed panorama.

• Journal of the Korean Society for Precision Engineering
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• v.20 no.2
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• pp.40-49
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• 2003

Ferrule is widely used as fiber optic connecters. In fiber-optic communications. the shape accuracy such as coaxiality and cylindricity of ferrule affects insertion loss. When coaxial grinding of ferrule supported by two pin. pin alignment and chucking accuracy are very important. In this research, the kinematic behavior of the ferrule centers are investigated in the case where the ferrule is chucked with the cone-shaped center pins and bail centers, With homogeneous coordinate transformation and numerical analysis, the obtained results are as follows: In the case of cone-type center, the alignment errors between center pins alone do not affect the rotation accuracy of ferrule. The alignment errors between center holes cause sinusoidal displacement of ferrule. And the maximum displacement of ferrule centers is proportional to the center pin angle. In the case of ball-type center, the displacements of ferrule centers has similar pattern as cone-type center, and the alignment errors art proportional to ball diameters.