• Journal of the Korean GEO-environmental Society
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• v.5 no.1
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• pp.65-73
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• 2004

The analysis of corrugated steel pipes is depending on a second dimension frame analysis or compressed ring model. This is the analysis not to consider the behavior of soil-structure interaction. The behavior of load resistance system is varied according to the depth of cover and the spacing of corrugated steel pipes structure. Therefore, the behavior characteristic of corrugated steel pipes was confirmed through finite element analysis to consider the activity of soil-structure interaction. If soil cover is filled up to the more of optimal depth, behavior of corrugated steel pipes are similar to those of ductile steel pipes according to the earth pressure distribution and effects of traffic loads are decreased. But, If soil cover is filled up to the less of optimal depth, corrugated steel pipes can't behave completely as ductile steel pipes because the passive earth pressure acting on side of corrugated steel pipes is decreased according to the decrement of vertical earth pressure, and the traffic loads influence on the section forces is increased, so that the traffic loads dominated the behavior of corrugated steel pipes.

• Geotechnical Engineering
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• v.9 no.1
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• pp.7-20
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• 1993

The first Korean earthquake resistant design code was enacted in 1988. In the code, the soil factor which takes into account both the soil amplification factor and the soil -structare interaction effect is divided into three groups : soil factor, 5 : 1.0, 1.2 and 1.5. In order to assist in choosing the soil factors appropriately in the earthquake resistant design, the local site effects on the based shear force induced by earthquakes are considered in depth for typical soil conditions in Korea. The depth of the alluvial and/or weathered zone is usually not deep and the fresh rock is found at depth shallower than 20 meters, and even at about 10 meters around Seoul. One dimensional wave propagation theory and the elastic half space method are used to obtain the soil -structure interaction effect as well as the soil amplification effect. The kinematic interaction effect due to scattering of waves by pile foundation is also considered. Finally, the soil factor is recommended for each soil condition from loose state to dense, and also from shallow soil depth to deep, so that the designer can choose the factor with-out difficulty.

• Transactions of the Korean Society of Machine Tool Engineers
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• v.16 no.6
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• pp.125-132
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• 2007

Inherent dynamic interaction between flexible disk and workpiece creates partially non-flat surface profile. A flat zone was defined using minimum depth of engagement. Several key parameters were defined to explain the characteristics of the zone. Process conditions including disk rotation speed, initial depth of cut and feed speed were varied to produce product profile database. Correlation between key factors was examined to find the characteristic dependencies. Trends of key parameters were displayed and explained. Higher flat zone ratio was observed for lower depth of cut and higher disk rotation speed. Ratio of minimum depth of cut against target depth of cut increased for higher feed speed and disk rotation speed but was insensitive to the depth of cut variation. The process transition was visualized by continuously displaying instantaneous orientation of the deflected disk and the location of key parameters were clearly marked for comparison.

• Corrosion Science and Technology
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• v.11 no.5
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• pp.157-164
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• 2012

In first experiment series, this paper is devoted for examining progress of reinforcement corrosion due to carbonation in concrete and to quantify uncarbonation depth to protect reinforcement from corroding. The tolerance of cover depth should be considered in order to prevent carbonation-induced corrosion. From the relationship between the weight loss of reinforcement and corrosion current density for a given time, therefore, the tolerance of cover depth to prevent carbonation-induced corrosion is computed. It is observed that corrosion occurs when the distance between carbonation front and reinforcement surface (uncarbonated depth) is smaller than 5 mm.As a secondary purpose of this study, it is investigated to examine the interaction between carbonation and chloride penetration and their effects on concrete. This was examined experimentally under various boundary conditions. For concrete under the double condition, the risk of deterioration due to carbonation was not severe. However, it was found that the carbonation of concrete could significantly accelerate chloride penetration. As a result, chloride penetration in combination with carbonation is a serious cause of deterioration of concrete.

• Coupled systems mechanics
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• v.7 no.4
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• pp.455-483
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• 2018

The study deals with physical modeling of a typical three storeyed building frame supported by a pile group of four piles ($2{\times}2$) embedded in cohesive soil mass using three dimensional finite element analysis. For the purpose of modeling, the elements such as beams, slabs and columns, of the superstructure frame; and that of the pile foundation such as pile and pile cap are descretized using twenty noded isoparametric continuum elements. The interface between the pile and the soil is idealized using sixteen node isoparametric surface element. The soil elements are modeled using eight nodes, nine nodes and twelve node continuum elements. The present study considers the linear elastic behaviour of the elements of superstructure and substructure (i.e., foundation). The soil is assumed to behave non-linear. The parametric study is carried out for studying the effect of soil- structure interaction on response of the frame on the premise of sub-structure approach. The frame is analyzed initially without considering the effect of the foundation (non-interaction analysis) and then, the pile foundation is evaluated independently to obtain the equivalent stiffness; and these values are used in the interaction analysis. The spacing between the piles in a group is varied to evaluate its effect on the interactive behaviour of frame in the context of two embedment depth ratios. The response of the frame included the horizontal displacement at the level of each storey, shear force in beams, axial force in columns along with the bending moments in beams and columns. The effect of the soil- structure interaction is observed to be significant for the configuration of the pile groups and in the context of non-linear behaviour of soil.

• Journal of the Earthquake Engineering Society of Korea
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• v.7 no.3
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• pp.57-67
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• 2003

Response analysis of buried pipeline subjected to permanent ground deformation(PGD) due to liquefaction is mainly executed by use of numerical analysis or semi-analytical relationship, When applying these methods, so called interfacial pipelineㆍsoil interaction force plays an dominant part. Currently used interaction force is mode up of indispensable mechanical and physical components for the response analysis of buried pipeline. However, it has somewhat limited applicability to the liquefied region since it is based on the experimental results for the non-liquefied region. Therefore, in this study, improved type of pipelineㆍsoil interaction force is proposed based on the existing interaction force and experimental research accomplishments. Above all, proposed interaction force includes various patterns of PGD or spatial distributions of interaction force caused by the decrease of soil stiffness. Through the comparison of numerical results using the proposed and the existing interaction force, relative influences of interaction force on the response of pipeline are evaluated and noticeable considerations in the application of semi-analytical relationship are discussed. Moreover, analyses due to the change of pipe thickness and burial depth are performed.

• Journal of the HCI Society of Korea
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• v.2 no.2
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• pp.1-9
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• 2007

In this paper, we propose a reconstruction technique of the lost hair region for 3D human actor modeling. An active depth sensor system can simultaneously capture both color and geometry information of any objects in real-time. However, it cannot acquire some regions whose surfaces are shiny and dark. Therefore, to get a natural 3D human model, the lost region in depth image should be recovered, especially human hair region. The recovery is performed using both color and depth images. We find out the hair region using color image first. After the boundary of hair region is estimated, the inside of hair region is estimated using an interpolation technique and closing operation. A 3D mesh model is generated after performing a series of operations including adaptive sampling, triangulation, mesh smoothing, and texture mapping. The proposed method can generate recovered 3D mesh stream automatically. The final 3D human model allows the user view interaction or haptic interaction in realistic broadcasting system.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.1 no.1
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• pp.26-31
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• 1963

1. This experiment was conducted with paddy rice in replicated field plot of clay load in Chung Puk College. This experiment has been intended to find out the suitable polt for increasing the yield of rice plant among the 36 plots which consist of 3 factors; deep plowing, heavy fertilizer and thick planting. 2 According to the standard and the heavy fertilizer applications, spikes and grains per phyung have been compared. It has been find out that the higher yield can be obtain in such plots as these; (1) the plot with standard fertilizer application, 15cm plowing depth and 400 hill per phyung, (2) the plot with two times as much fertilizer application, 30 cm plowing depth and 300 hills per phyung, (3) the plot with three times as much fertilizer application, 30cm plowing depth and 300 hills, or 45cm plowing depth and 400hills per phyung. 3. In the yield of brown rice, there has been significant difference in each main factor: hills per phyung, the plowing depth and the amount of fertilizer, and in the first order interaction; depthxfertilizer, depthxhills and hillsxfertilizer, and in the 2nd order interaction; depthx hillsxfertilizer. 4. In the plots with 30cm plowing depth, thick, planting of 200∼300 hills per phyung and two times as much fertilizer, the yield of rice has been superior to others.

• Journal of Korean Institute of Industrial Engineers
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• v.30 no.4
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• pp.267-276
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• 2004

Much of previous attention on researches of the decision tree focuses on the splitting criteria and optimization of tree size. Nowadays the quantity of the data increase and relation of variables becomes very complex. And hence, this comes to have plenty number of unnecessary node and leaf. Consequently the confidence of the explanation and forecasting of the decision tree falls off. In this research report, we propose some decision tree algorithms considering the interaction of predictor variables. A generic algorithm, the k-1 Algorithm, dealing with the interaction with a combination of all predictor variable is presented. And then, the extended version k-k Algorithm which considers with the interaction every k-depth with a combination of some predictor variables. Also, we present an improved algorithm by introducing control parameter to the algorithms. The algorithms are tested by real field credit card data, census data, bank data, etc.

• Geomechanics and Engineering
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• v.23 no.6
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• pp.547-560
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• 2020

This paper studies the dynamic foundation-soil-foundation interaction for two square rigid foundations embedded in a viscoelastic soil layer. The vibrations come from only one rigid foundation placed in the soil layer and subjected to harmonic loads of translation, rocking, and torsion. The required dynamic response of rigid surface foundations constitutes the solution of the wave equations obtained by taking account of the conditions of interaction. The solution is formulated using the frequency domain Boundary Element Method (BEM) in conjunction with the Kausel-Peek Green's function for a layered stratum, with the aid of the Thin Layer Method (TLM), to study the dynamic interaction between adjacent foundations. This approach allows the establishment of a mathematical model that enables us to determine the dynamic displacements amplitude of adjacent foundations according to their different separations, the depth of the substratum, foundations masss, foundations embedded, and the frequencies of excitation. This paper attempts to introduce an approach based on a polynomial mathematical tool conducted from several results of numerical methods (BEM-TLM) so that practicing civil engineers can evaluation the dynamic foundations displacements more easy.