• 한국식품과학회지
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• 제17권3호
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• pp.208-212
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• 1985

이륜형 식품 압출기에서 체류시간의 분포에 대한 reverse screw element의 효과를 보기 위하여 여러가지 screw 조합에 따른 체류시간의 분포를 실험적으로 평가 하였다. Forwarding screw에서 형성된 C. chamber의 수를 평가하기 위해 아래와 같은 model equation을 도출 하였다. $T=T_x+\frac{1}{x}(\sum\frac{l}{a}+\frac{V{\cdot}\rho}{F/x})$ Reverse screw element를 사용함으로써 체류시간 분포 곡선은 넓게 퍼지는 경향이 있었고 최대 peak에 도달하는 시간이 증가 하였다. True residence time은 die 바로 앞에 있는 reverse screw element에 의해 주로 영향을 받았다. Filled C-chamber의 수는 같은 형태의 screw조합에서는 screw 회전수가 증가함에 따라 감소하였다.

• Geomechanics and Engineering
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• 제10권5호
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• pp.577-598
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• 2016

This paper presents a numerical study of pile force distribution in a pile group foundation subjected to vertical load and large moment. The physical modeling of a pile foundation for a wind turbine is analyzed using 3D finite element software, PLAXIS 3D. The soil profile consists of several clay layers, which are modeled as Mohr-Coulomb material in an undrained condition. The piles in the pile group foundation are modeled as special elements called embedded pile elements. To model the problem of a pile group foundation, a small gap is created between the pile cap and underlying soil. The pile cap is modeled as a rigid plate element connected to each pile by a hinge. As a result, applied vertical load and large moment are transferred only to piles without any load sharing to underlying soil. Results of the study focus on pile load distribution for the square shape of a pile group foundation. Mathematical expression is proposed to describe pile force distribution for the cases of vertical load and large moment and purely vertical load.

• 한국해양공학회지
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• 제24권2호
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• pp.34-40
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• 2010

When a large ship is advancing in waves, it undergoes hydroelastic response, which affects the structural stability and the fatigue destruction of the ship. Therefore, to predict an accurate hydroelastic response, it is necessary to conduct a thorough analysis of hydroelastic response, including fluid-structure interactions. In this research, the ship is divided into many hull elements, to calculate the fluid forces and wave exciting forces on each element. Using the three-dimensional source distribution method, the calculated fluid forces and wave exciting forces are assigned to nodes of the hull elements. The neighbor nodes are connected with elastic beam elements. We analyzed hydroelastic responses, using the finite elements method.

• Journal of Welding and Joining
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• 제21권6호
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• pp.77-83
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• 2003

The finite element analysis was performed for the cracks existing in residual stress fields in order to investigate the effects of configuration of residual stress distribution to the fatigue crack opening behaviour. And the variation of stress distributions adjacent to the crack caused by uploading was examined. The finite element model with contact elements for the crack plane and plane stress elements for the base material and the analytical method based on the superposition principle to estimate crack opening behaviour and the stress distribution adjacent to the crack subjected to uploading were used. The results of the analysis showed that crack opening behaviors and variations of stress distribution caused by uploading were changed depending on the configuration of residual stress distribution. When the crack existed in the region of compressive residual stress and the configuration of compressive residual stress distribution were inclined, a partial crack opening just behind of a crack tip occurred during uploading. Based on the above results, it was clarified that the crack opening behaviour in the residual stress field could be predicted accurately by the finite element analysis using these analytical method and model.

• 한국조경학회지
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• 제49권6호
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• pp.80-92
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• 2021

태산(泰山)은 해발 1,532m로 중국에서 제일 높은 산이 아님에도 불구하고 '오악독존(五嶽獨尊)'과 같은 높은 명성을 가지고 있다. 역대 문인 묵객들은 태산 경관을 원천으로 삼아 많은 작품을 만들었다. 전통문학은 민족의 특징과 풍모를 그대로 반영한 민족 문화로서 인문 과학의 중요한 부분이고 원림과 일맥상통한다. 이에 본 연구는 전통문학의 대표적인 시문(詩文)에 나타난 태산 경관요소에 대해서는 경관유형 및 요소 분석과 경관요소의 핵밀도(kernel density), 평균중심(mean center), 표준차타원(standard deviational ellipse) 분석을 통해 경관요소 및 분포의 특성을 시대별로 파악하였다. 연구 결과를 요약하면, 첫째, 태산의 경관유형은 인간활동이 가장 많이 나타났으며, 이는 지금까지의 풍경명승지와 관련된 선행연구의 자연경관과는 다르다. 둘째, 태산의 경관요소 가운데 '일출', '청색', '우뚝'과 '웅장', '신룡'의 중요성을 확인하였으며, 이는 태산의 희망과 광명, 활기참, 국가 안정과 번성, 우두머리의 지위를 상징하는 것으로 해석할 수 있다. 셋째, 시대별 경관요소는 선진과 수당시대에 신앙(봉선, 신선)이 많이 나타났고 근현대에는 행동(등반, 멀리 바라보기)이 많이 나타났다. 이는 신앙경관에서 경관 체험위주로 변했다고 할 수 있다. 넷째, 경관요소의 공간분포는 전시대에 걸쳐 태산 대정(岱頂)에 많이 분포되어 있고, 근현대로 올수록 평균중심이 태산 외부의 남쪽에서 태산정상 중심으로 이동하였으며, 넓은 분산 분포에서 태산을 중심으로 좁은 선형 분포로 변했다. 본 연구의 결과는 향후 태산의 경관 보전 및 복원에 중점을 두어야 할 요소나 공간을 제시하는데 의의가 있다.

• Computers and Concrete
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• 제20권1호
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• pp.11-22
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• 2017

There are two methods to model the plastification of members comprising lumped and distributed plasticity. When a reinforced concrete member experiences inelastic deformations, cracks tend to spread from the joint interface resulting in a curvature distribution; therefore, the lumped plasticity methods assuming plasticity is concentrated at a zero-length plastic hinge section at the ends of the elements, cannot model the actual behavior of reinforced concrete members. Some spread plasticity models including uniform, linear and recently power have been developed to take extended inelastic zone into account. In the aforementioned models, the extended inelastic zones in proximity of critical sections assumed close to connections are considered. Although the mentioned assumption is proper for the buildings simply imposed lateral loads, it is not appropriate for the gravity load effects. The gravity load effects can influence the inelastic zones in structural elements; therefore, the plasticity models presenting the flexibility distribution along the member merely based on lateral loads apart from the gravity load effects can bring about incorrect stiffness matrix for structure. In this study, the linear flexibility distribution model is improved to account for the distributed plasticity of members subjected to both gravity and lateral load effects. To do so, a new model in which, each member is taken as one structural element into account is proposed. Some numerical examples from previous studies are assessed and outcomes confirm the accuracy of proposed model. Also comparing the results of the proposed model with other spread plasticity models illustrates glaring error produced due to neglecting the gravity load effects.

• 오토저널
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• 제3권3호
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• pp.24-29
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• 1981

This paper is studied an efficient temperature distribution and heat transfer of two-dimensional rectangular cross-section by the higher-order triangular finite dynamic element and finite difference. This is achieved by employing a discretization technique based on a recently developed concept of finite dynamic elements, involving higher order dynamic correction terms in the associated stiffness and convection matrices. Numerical solution results of temperature distribution presented herein clearly optimum element and show that FEM10 is the most accurate temperature distribution, but heat transfer and computational effort is the most acquired.

• 전기의세계
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• 제30권12호
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• pp.811-816
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• 1981

In this paper, the finite element method is applied to find the flux distribution of the magnetic field in the end region of the tubular motor. In order to analyze two-dimensional flux distribution, the r-z domain to be analyzed is subdivided into 56 nodes, 84 elements. In the case of wt=O and .pi./2, the flux distribution is shifted to the edge with frequency (w) and time (t) increase in the edge and the air gap. It is proved that this study does fit the actual phenomena.

• 한국측량학회지
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• 제16권2호
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• pp.225-233
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• 1998

수질오염 현상을 규명하기 위해서는 지속적으로 호수의 수질을 조사할 필요가 있는데 이것은 시간과 경비가 많이 소요될 뿐만 아니라 광범위한 지역을 조사하기가 상당히 어렵다. 그러나 인공위성에 의한 원격탐사 기법은 동시에 넓은 지역에 걸쳐 수질상태를 측정할 수 있고 또한 주기적으로 동일 지점을 측정할 수 있기 때문에 수질을 조사하는데 효과가 크다. 또한 Landsat의 센서들 중에는 파장별로 물체를 감지하는 특성이 있어서 수질의 분포를 단시간내에 비교적 정확하게 확인해 낼 수 있으며 그 영상을 Color로 표현하는 것이 가능하다. 따라서 본 연구는 인공위성 자료를 이용하여 투명도, 수심, 표층수온 등 수질인자 추출을 시도하고 그에 따른 수질인자 실험식을 제시하여 화진포호의 수질분포 영상도를 작성하였다. Landsat TM 영상의 DN으로부터 수질인자를 추출하고 이것을 다시 GIS를 이용하여 TIN분석을 한 후 수질분포 영상도를 작성하면 실제 관측하여 얻어진 값을 이용하여 나타낸 것 보다 광범위한 지역에 대하여 비교적 정확한 패턴임을 알 수 있다.

• Journal of Plant Biology
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• 제31권3호
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• pp.169-185
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• 1988

Vessel elements in lateral root, tap root, transition region, stem and mid vein of 1-year old, 3-year old and 5-year old ginseng (Panax ginseng C.A. Meyer) are studied with light microscope to clarify the distribution and differentiation of several kinds of vessel elements. Vessel elements are classified into five types such as ring vessel, spiral vessel, scalariform vessel, reticulate vessel and pitted vessel according to the secondary thickenings of cell wall. All of the five types are not observed in each organ, but diverse kinds of vessels are present in stem and mid vein compared with the underground organs such as tap root and lateral root. The length of vessel elements is longest (680$\mu$m) in stem and shortest (143$\mu$m) in tap root. The diameter of vessel elements is 19.0$\mu$m in tap root and the angle of perforation plate comes under 22$^{\circ}$-60$^{\circ}$. The degree of differentiation of vessel elements according to the length, diameter and angle of perforation plate of vessel elements is highest in tap root regardless of the age of ginseng. Three types of perforation plate such as scalariform, intermediate type of simple and scalariform, and simple perforation plate are observed. The vascular tracheids are characteristically observed in mid vein of 1-year old ginseng, and in transition region of 3 and 5-year old ginseng.