• Proceedings of the Korean Society of Precision Engineering Conference
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• 2004.05a
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• pp.325-325
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• 2004

최근 UC 공작기계의 활용성 및 산업전반에 차지하는 중요성이 날로 증가하고, If기술을 접목한 네트워크 솔루션의 비약적인 발달에 힘입어 대부분의 공정들이 자동화됨에 따라 최종 부품의 가공정밀도는 전적으로 CNC 공작기계에 의존한다고 할 수 있다. 그러나 공작기계 각 구성 부품들의 가공오차와 조립 시 발생하는 기하학적 오차, 장시간 사용으로 인한 마모, 구조물의 온도 상승에 따른 열팽창 등으로 인하여 공구와 공작물간에 상대적인 공칭거리와 실제로 운동하는 거리와의 차이가 발생한다.(중략)

• Journal of the Korean Society of Industry Convergence
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• v.25 no.6_2
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• pp.1091-1095
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• 2022

Dynamic stability of the main spindle system shall be ensured when operating the planer miller for remanufacturing the planer miller. This paper explains the analysis process that determines the stability of the planer miller spindle system in the design stage using ANSYS, an analysis program. First, the dynamic stability of the main spindle system is verified through risk speed analysis in the rated RPM range of the planer miller through ANSYS Modal Analysis, and second, the stability and durability of the main spindle system are verified through ANSYS nCode Analysis.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2002.10a
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• pp.26-31
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• 2002

The recent machine tools are requested so high-quality processing and productivity increasing. Therefore, it is so necessary to develop technology fur high-speed and high-precision. This thesis touches on the development of high speed and intellectual line center. At first, the line center is necessary that strong structure, compact structure and light weight design for high-speed processing and transfer. So, it is necessary that examination of new materials and structures for light-weight and control devices for precision processing. So. it is going to make mention of the process of 1st model production for the above-mentioned based on test model production and evaluation.

• Proceedings of the Korea Concrete Institute Conference
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• 2008.11a
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• pp.45-48
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• 2008

Under earthquake loads, the columns on the lower stories carry large axial forces and horizontal forces as the earthquake loads are acting horizontally and vertically on the building. To distribute the energy entered into the building under earthquakes according to the plastic deformation of the members, it is safer and more economic to persuade plastic hinge to occur in the beams rather than on the columns. However, it is unavoidable to have plastic hinge occurring on the columns when it is applied on both of the main axes of the building, which results in high shear force on the column end, and reinforced concrete column may result in sudden brittle failure due to bending moment and shear force. To increase restriction of the reinforced concrete column on the horizontal forces, this study uses repetitive loading experiments with different amount of shear reinforcement, and analyzes and compares the structural safety and behaviour of the reinforced test materials.

• Journal of the Korea institute for structural maintenance and inspection
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• v.21 no.1
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• pp.126-133
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• 2017

This paper presents the shear capacities of hollow slab with plate and octagonal pillar type hollow sphere. Recently, the interest in precast hollow slab system for buildings is growing up according to the demand for high quality control and the increase in slab thickness. A hollow slab system is widely known as one of the effective slab system which can reduce self-weight of slab. However, hollow slabs are vulnerable to the deterioration in the shear strength due to the decrease of concrete at slab web which resists shear. Especially, in case of precast hollow slabs, it has joint surface between precast concrete slab modules along transverse axis of slab, and shear failure, that is caused by cracks at joints, has to be prevented. Therefore, in this study, shear capacity of the I-slab system is evaluated by 3-points-supported shear test along the longitudinal and transverse axis of slab specimen. Test results showed that I-slab had enough shear strength compared to theoretical shear strength even if it included the joint surfaces.

• Journal of Fisheries and Marine Sciences Education
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• v.7 no.1
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• pp.14-30
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• 1995

한국(韓國)의 연근해어업(沿近海漁業)은 국내외 여건의 변화로 경쟁력(競爭力)을 잃어가고 있다. 따라서 구조개선(構造改善)을 통한 활로개척의 필요성이 강하게 대두되고 있으나, 중앙정부(中央政府) 차원의 어업여건(漁業與件) 개선은 장기간이 소요될 것으로 예상된다. 따라서 지방화시대(地方化時代)를 맞이하여 수산정책(水産政策)도 지방정책(地方政策)에 의한 지역적 특성을 가진 정책으로 발전시켜나갈 필요가 있다. 여기에서는 그런 차원에서 본토(本土)와는 지리적(地理的), 사회적(社會的), 경제적(經濟的)으로 상당히 독립된 특성을 가지고 있는 제주도(濟州道)에 있어서의 연근해어업(沿近海漁業)에 관한 각종 자료를 이용하여 어업의 현황을 분석하고, 나아가 생산성(生産性)을 보다 향상시킬 수 있는 어업구조(漁業構造)의 개선방향(改善方向)에 관하여 연구하였다. 그 연구결과(硏究結果)는 다음과 같다. 1. 제주도(濟州道) 연근해어업(沿近海漁業)의 실태(實態) 1) 어업인구(漁業人口)는 계속 감소하고 있으며 부녀자(婦女子) 비율이 뚜렷하게 높다. 2) 어선세력(漁船勢力)은 10톤이하의 소형선(小型船)이 꾸준히 증가되고 있으며, 10~50톤급의 증가률(增加率)도 매우 높다. 3) 어항(漁港)은 107개가 있으나 그중 80%는 비법정(非法定)의 소규모(小規模) 어항(漁港)이었다. 4) 어선어업(漁船漁業)은 연승(延繩) 유자망(流刺網) 채낚기 분기초망어업(焚寄抄網漁業) 등을 중심으로 이루어지고 있다. 5) 생산물(生産物)의 종류는 어류(魚類)가 주축을 이루고 있고, 대부분 고급(高級) 어종(魚種)이며, 가격은 상당히 높다. 6) 어선어업(漁船漁業)의 한어기(閑漁期)에 관광산업(觀光産業)과 연계하여 운영하고 있는 유어어업(遊漁漁業)은 상당히 발전할 소지를 가지 고 있다. 2. 문제점(問題點) 1) 어업인구(漁業人口)는 감소하는 반면 부녀자(婦女子)의 참여율은 높아 어선어업(漁船漁業)에 종사할 인력의 수급이 어려우며, 이것이 조업규모(操業規模)를 지속적으로 확대하지 못하는 요인이 되고 있다. 2) 어항시설(漁港施設)이 미비하여 어선어업(漁船漁業)의 규모를 확대시키기가 곤란하다. 3) 연근해어업(沿近海漁業) 어획물(漁獲物)의 판매를 위한 제도 및 시설이 소비환경(消費環境) 및 기호변화(嗜好變化)에 적절히 대응하지 못하고 있다. 4) 유어어선(遊漁漁船)의 운영기반(運營基盤)이 취약하여 활성화되지 못하고 있다. 5) 어업의 경쟁력 확보를 위한 기술교육(技術敎育) 및 연구(硏究) 지도체제(指導體制)가 취약하다. 3. 구조개선(構造改善)의 방향(方向) 1) 어업인력(漁業人力)의 안정적인 수급(需給)을 위하여 어민(漁民)의 정주환경(定住環境)을 개선하고, 어민후계자(漁民後繼者) 육성사업(育成事業)의 자금지원 수준을 향상시켜야 하며, 수산고등학교(水産高等學校) 졸업자(卒業者)를 수산계대학(水産系大學)에 일정 비율 정원외(定員外) 특예입학(特例入學) 시킴으로써 기술(技術)의 고도화(高度化)와 어촌 정착 동기를 높여 주어야 한다. 2) 어업인력(漁業人力) 감소에 대비하여 어선의 장비를 현대화, 생력화(省力化)하여 적은 인력으로도 운영이 가능하도록 유도하여야 한다. 3) 어업의 경쟁력 확보를 위해 어항시설(漁港施設)을 확충하고, 소비자(消費者)의 기호변화(嗜好變化)에 대응하여 위탁판매(委託販賣) 장소를 중심으로 종합어시장(綜合魚市場)을 개설해야 하며, 이와는 별도로 활어위판장(活魚委販場)을 시설하여 어획물(漁獲物) 부가가치제고(附加價値提高) 및 유통개선(流通改善)을 이루어야 할 것이다. 4) 유어어선(遊漁漁船)의 운영도 편의시설(便宜施設)을 확충하고 인공어장(人工漁場)의 조성을 추진하여 안정적인 부업으로 정착될 수 있도록 하는 노력이 필요하다. 5) 연구(硏究) 지도(指導)의 강화를 위하여 제주도(濟州道)에 소재하고 있는 연구(硏究) 지도기관(指導機關)을 적극적으로 활용함은 물론, 필요하다면 기관을 개편 증설하고, 어업인력(漁業人力)의 질적 향상을 위한 어민교육원(漁民敎育院)의 설립도 검토해 볼 필요가 있다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.37 no.5
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• pp.449-457
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• 2013

In this study, we performed a numerical analysis to investigate the effect of rotation on the blood flow and arterial wall behavior by using the FSI (fluid-structure interaction) technique. The geometry of the artery included 50% stenosis at the center. To simulate the rotational effect, 2-6 rps of axial velocity was applied to the arterial model. A spiral wave and asymmetric flow occurred due to the stenosis and axial rotation both in the rigid body model and in the FSI model. However, the arterial wall motion caused periodic and transient blood flow changes in the FSI model. The FRZ (fluid recirculation zone) decreased in the FSI model, which is a known predictor for the formation and vulnerability of plaque. Therefore, it is observed that arterial wall motion also influences the generation of the FRZ.

• Korean Journal of Plant Taxonomy
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• v.34 no.2
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• pp.97-118
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• 2004

A comparative anatomical and ultrastructural study was undertaken to investigare on the leaf epidermis by light microscopy (LM) and scanning electron microscopy (SEM). On the basis of results from this study, it was grasped major characters of taxa and variation range of each character on the level of species, section and subgenus respectively. The shape of leaf epidermal cell was oblong to linear, which was varied by each taxon. Epidermal cell of taxa in sects. Microscordum, Anguinum, and Rhizirideum, which had wide leaf blade, oblong instead of linear shape in others examined taxa in this study. The leaf of taxa in sect. Anguinum was hypostomatic, while the rest of taxa had amphistomatic leaf. This was also one of characters which could discriminate taxa of sect. Anguinum from others. The guard cell in investigated taxa had not so much variation in the respect of its size. The number of stomata per unit area reduced by increasing size of epidermal cell, the fewest number of stomata per unit area was found in the taxa of sect. Anguinum. The type of stomatal apparatus of observed all taxa was anomocytic. It was found to know ultrastructural variation in the epidermal cell, like as patterns of sculpture on the cell wall, and features of deposition of wax by SEM. There were no depositions of wax in the taxa of sect. Microscordum and Anguinum, but fine thread-like structures which were parallel or cross to axis was found on the surface of epidermal cell respectively. The patterns of sculpture on the cell were prominent straight in sects. Recticulato-bulbosa and Rhizirideum, discontinuous line in the sect. Oreiprason. The epicuticular wax had been deposited on the surface of its epidermal cell in all taxa except sects. Microscordum and Anguinum.

• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.29 no.1
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• pp.90-104
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• 2011

This study identified the scenic characteristics in Gugok and symbolism reflected in titles of the scenery of the season in Gugok from a perspective of Sundoism concentrated on Galeun Gugok in Goisan which is influenced most greatly by Sundoism hermit ideas in Korea, along with Seonyudong-Gugok. In addition, it suggested a measure for arrangement and narrative Storyboard of Galeun Gugok structure corresponding with promotion and propagation of Gugok cultural scenes and educational goals. According to analysis and interpretation of the various Gugoks forming Galeun Gugok in terms of their titles, names engraved in surrounding elements and the coherent symbolic meanings of its scenery and place through comparison with secenery of near Seonyudong-Gugok, the result shows that Galeun Gugok comprises wishes for eternal life in the forms of Taoist hermit-related scenery of the season within the range of stream and old stories based on environmental affordance. In figurative way, it ultimately presents the Wonyung(圓融) idea which seeks a harmonious combination of God and humankind. In particular, consciousness of longevity without problems is deeply inherent in the background of eternalness of plants, divinity of animals and natural homeostasis. Also, 9 Gok Seongukam set up at visual terminal reflect noticeably that a game Go is the amusement of the immortals, which describe 9 ranks of GO figuratively. Galeun Gugok is formed in a unity structure, which is hermit-oriented Sundoism and motif, such as longevity and immortality, divinity and enjoyment of Sundoism hermit rather than used as a method to achieve taste for the arts or ethics. Given the fact, it presents eternal longevity and atmosphere of seclusion in very strong way. Development of spatial Storyboard structure based on this is interpreted as 'Entering the world of hermits(Introduction)'-'Looking the world(Development)'-'Living with hermits(Turn)'-'Becoming hermit(Conclusion).' Finally, the scenery image of Galeun Gugok presented in surface structure is based on beauty of the immortal land scenery as well as beauty of pre-achieved space in Gugokdongcheon and arranged the vertical narrative structure as divine space of 9 ranks of GO. Taking those into account, scenery story board of Galeun Gugok was suggested in accordance with a theme of 6 cuts; Gnagsun(降仙)-Sungyeong(仙境)- Sunyak(仙藥)-Sunhak(仙鶴)-Sunyu(仙遊)-Eunsun(隱仙). It is obvious that hermit which live an eternal life as a representative of Sundoism, should be the main motif of scenery planning in a filed of modem landscaping. Therefore, the most valuable component in designing Korean landscape must be the homeostasis of surrounding landscape which supports the characteristics of invariability and divinity of nature.