• Journal of the Korean Institute of Traditional Landscape Architecture
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• v.35 no.4
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• pp.75-87
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• 2017

This study is the research about Okcheonjeong(玉泉亭) located in the backyard of Namhansanseong(南漢山城)'s temporary palace(行宮). Okcheonjeong was not only built by a government inside Namhansanseong but it was also representative garden which is shown the culture of the nobility. It became famous garden ruins recently because it has remained many carved stones. However, there has been no study about Okcheonjeong yet. We studied Okcheonjeong to establish basic knowledge by literature analysis and field investigation. We tried to discover garden style by deciphering carved stones, and estimate Okcheonjeong's location by documentary research. Sim, Sang-Gyu became Gwangjuyusu(廣州留守) in 1816, and he built Okcheonjeong on the backyard of Namhansanseong's temporary palace in 1817. It was located in the foot of a mountain beside a stream. It consisted of Pungaepok(楓靄瀑: waterfall), Chusudam(秋水潭: a little pond), and Okcheon(玉泉: a stone wall). The stone for sign stands in front of the entrance of Pungaepok to show Okcheonjeong, and there is Yeongyeondae(泠然臺) above the waterfall. We thought that Okcheonjeong was typical Imcheon-garden(林泉庭苑). Okcheonjeong is located in the foot of a mountain following Gamigyeong(歌薇逕) 60 meters so it was able to see the whole temporary palace from the Okcheonjeong. It was the garden pavilion of temporary palace, but it was used in semi public garden(半公的庭苑). Okcheonjeong is the only graden ruins which was located in Namhansanseong, so we have to preserve as cultural heritage. We expect to make use of primary datas to restore Namhansanseong soundly which was world heritage.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.39 no.7
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• pp.713-720
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• 2015

The sizes of the final blades of a low-pressure (LP) steam turbine have been getting larger for the development of high-capacity power plants. They are also larger than the other blades in the same system. As a result, fatigue damage is caused by a large centrifugal force and a low natural frequency of the blade. Recently, many failure cases have been reported due to repeated turbine startups and their prolonged use. In this study, the causes and mechanism of failure of a LP turbine blade were analyzed by using a finite element method to calculate the centrifugal force, the natural frequency of a stress-stiffening effect, and the harmonic response. It was observed that the expected fatigue damage position matched the real crack position at the airfoil's leading edge, and an equivalence fatigue limit approached a notch fatigue limit.

• Journal of the Korean Recycled Construction Resources Institute
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• v.5 no.4
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• pp.99-105
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• 2010

This study analyzed the effects of changes in mixing factors of zero-cement mortar that only used recycled fine aggregates and fly-ash on quality of mortar, and the results are as follows. To describe the property of fresh mortar, as mix proportion and flow of mortar increased, W/B was highly selected and air content decreased. To describe compressive strength according to age as the property of hardened mortar, it was revealed that the strength did not strength until the 14 day, but strength of about 1 ~ 2 MPa strength during the 14 day through 28 day, and almost similar strength after 28 day. Also, compressive strength according to changes in mix proportion, flow and B/W was generally similar. Summarizing the above experimental results, in case of mortar that used recycled fine aggregates and fly-ash, it secured the strength for the use of landfill even though not for structural use. Especially, poor mix proved to be more useful than rich mix.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2005.06a
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• pp.672-675
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• 2005

To imprint 70-nm wide line-patterns, we used a newly developed ultraviolet nanoimprint lithography (UV-NIL) process in which an elementwise patterned stamp (EPS), a large-area stamp, and pressurized air are used to imprint a wafer in a single step. For a single-step UV-NIL of a 4' wafer, we fabricated two identical $5'\times5'\times0.09'(W{\times}L{\times}H)$ quartz EPSs, except that one is with nanopatterns and the other without nanopatterns. Both of them consist of 16 small-area stamps, called elements, each of which is $10\;mm\;\times\;10\;mm$. UV-curable low-viscosity resin droplets were dispensed directly on each element of the EPSs. The volume and viscosity of each droplet are 3.7 nl and 7 cps. Droplets were dispensed in such a way that no air entrapment between elements and wafer occurs. When the droplets were fully pressed between ESP and wafer, some incompletely filled elements were observed because of the topology mismatch between EPS and wafer. To complete those incomplete fillings, pressurized air of 2 bar was applied to the bottom of the wafer for 2 min. Experimental results have shown that nanopatterns of the EPS were successfully transferred to the resin layer on the wafer.

• Korean Journal of Materials Research
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• v.21 no.5
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• pp.283-287
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• 2011

As the performance of microelectronic devices is improved, the use of copper as a heat dissipation member is increasing due to its good thermal conductivity. The high thermal conductivity of copper, however, leads to difficulties in the joining process. Satisfactory bonding with copper is known to be difficult, especially if high shear and peel strengths are desired. The primary reason is that a copper oxide layer develops rapidly and is weakly attached to the base metal under typical conditions. Thus, when a clean copper substrate is bonded, the initial strength of the joint is high, but upon environmental exposure, an oxide layer may develop, which will reduce the durability of the joint. In this study, an epoxy adhesive formulation was investigated to improve the strength and reliability of a copper to copper joint. Epoxy hardeners such as anhydride, dihydrazide, and dicyandiamide and catalysts such as triphenylphosphine and imidazole were added to an epoxy resin mixture of DGEBA and DGEBF. Differential scanning calorimetry (DSC) analyses revealed that the curing temperatures were dependent on the type of hardener rather than on the catalyst, and higher heat of curing resulted in a higher Tg. The reliability of the copper joint against a high temperature and high humidity environment was found to be the lowest in the case of dihydrazide addition. This is attributed to its high water permeability, which led to the formation of a weak boundary layer of copper oxide. It was also found that dicyandiamide provided the highest initial joint strength and reliability while anhydride yielded intermediate performance between dicyandiamide and dihydrazide.

• Journal of Chest Surgery
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• v.30 no.2
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• pp.226-230
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• 1997

This is a case report of surgical management of a bilateral intralobar pulmonary sequestration with horseshoe lung presenting with frequent U I with productive sputum. Simple chest X-ray showed pneumonic consolidation and infiltration on both lower lobes, and chest CT revealed multiple cystic lesions compatible with pulmonary sequestration. The aortography demonstrated two anomalous systemic arteries arising from the thoracic aorta just above the diaphragm to both sequestrums. Left lower lobectomy was performed through the left thoracotomy with ligations and divisions of the both systemic feeding arteries to the left and right sequestrum, and division of the isthmic portion of horseshoe lung without removal of right sequestrum. The patient was discharged on the postoperative loth day and followed-up till now without any sequelae and symptoms of residual right sequestration. The recent follow-up chest CT 5 months after the operation revealed spontaneous regression of the residual right sequestrum. Authors would suggested that only division of aberrant artery to sequestrum without lobectomy may be applied in uncomplicated ca e of intrapulmonary seqilestration.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.21-21
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• 2012

수송용 산업의 하나인 국내 조선업계는 2008년 말 이후 세계 조선경기 불황 속에서도 2009년 451억달러, 2010년 491억달러의 사상최대 수출액을 달성한 바가 있고 세계 조선사 순위에서는 1위에서 5위까지 한국 조선소 등이 우위를 차지하고 있다. 그러나 개별 기업 경쟁력은 우위에 서있지만 중국과의 격차가 많이 좁혀지고 있어 안심할 수 없는 상황이다. 특히 최근에는 탄소배출량이 적은 친환경 선박의 제조가 선박업계 전반의 화두로 대두되고 있다. 이를 위해 다양한 시도가 시도되고 있는데 그중에 하나가 선박의 경량화이다. 금속외장 전선은 선박 무게의 10~13%를 차지하고 있고 전체 사용 전선의 30~40%를 차지하고 있어 선박에서의 금속외장 전선의 무게를 줄이기 위한 연구가 필요한 실정이다. 또한 조선산업 뿐만 아니라 자동차 분야에서도 금속 외장전선이 많이 사용되고 있으며, 자동차의 연비 향상을 위한 경량화 연구가 더욱 절실한 상황이다. 본 연구에서는 수송용으로 사용되는 전선의 금속외장을 경량 고강도 섬유를 활용한 하이브리드 wire로 대체하기 위한 편조 기술 및 편조 장치를 개발하기 위한 설계 및 기초연구를 수행하였다. 초경량 고강도 섬유 Armor의 제조기술 및 최적 공정 개발을 위한 연구로서 경쟁사 샘플에 대한 분석을 실시하였고, 사용된 섬유의 성분 분석 및 물성시험을 수행하였다. 또한 원형직기 개발을 위한 구조부 설계를 위해 ANSYS해석을 수행하고 저신율 고강도인 아라미드의 이징모션 시스템 개발을 위한 연구를 수행하였으며 개구 형성방법을 설계하였다. 그리고 초경량 고강도 hybrid 케이블 아라미드 편조 표면 및 내부 가교에 의한 가공 기술을 연구하였다. 아라미드 섬유의 발수성 향상을 위한 코팅재료 선정을 위한 연구를 수행하였고, 자외선 경화공정에서 조건별 데이터를 정립하여 솔루션을 제공하고자 한다.

• Korean Journal of Environmental Agriculture
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• v.17 no.4
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• pp.358-361
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• 1998

This study was carried out to develop a short term hardening method of tree seedlings of Rhus chinensis Mill., Evodia daniellii Hemsley and Parthenocissus tricuspidata(Sieb. et Zucc.) Planck for afforestation on a concave and a crack of cut-rock slope. The seedlings were grown in a cylinder shaped pot made of polyvinyl net with the soil media of peatmoss, vermiculite, clay, compost, fertilizer, and absorbant(40:25:19:15:1:0.1, v:v). They were cultivated in a greenhouse for four months and in field condition for two months. During the last three months of the growing period the seedlings were hardened by periodic desiccation and irrigation in 4 to 10 days interval. The hardened seedlings showed lower leaf water potential, higher leaf osmotic pressure, and lower T/R ratio than those before the hardening. The hardened seedlings survived well on the soil medium in the concave of cut-rock slope.

• Journal of the Korean Applied Science and Technology
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• v.32 no.3
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• pp.528-535
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• 2015

Humanity has tended pursuing beauty. Pearls has been loved by many people for thousands of years as a symbol of wealth and status. Today, Artificial pearl were made using organic pigment due to bright colors and easy coating process. But the new coating technique is required due to low durability, weather resistance and difficulty of luxurious luster expression. This study, nitrocellulose and urethane were used as binder and inorganic pigment were used to expression of colors. Experimental variable of artificial pearl with nitrocellulose and solvent ratio, urethane and curing agent ratio, the amount of pearl number of coating, drying temperature and time, and coating technology was developed. The coated artificial pearl was evaluated with color-difference meter, ultraviolet ray resistance, promotion weathering. Urethane was better than nitrocellulose when compared with weather resistance, acid-alkalinity resistance.

• The Journal of the Korean bone and joint tumor society
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• v.7 no.2
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• pp.68-72
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• 2001

Adamantinoma is a rare malignant tumor and approximately 85% of cases occur in the tibia. In 1985, Moon and Mori reviewed the world literature and identified 195 cases. A 59-year-old woman was presented with nonspecific pain on left leg after trauma. Radiographic finding showed well-circumscribed soap bubble appearance with areas of sclerosis in diaphyseal region of the tibia. Magnetic resonance imaging and biopsy was performed for diagnosis. Histologically, the lesion was compatible with adamantinoma. Wide resection with bone graft was performed. There was no recurrence at 3 years follow-up. We report a case of adimantinoma that arose in diaphyseal region of the tibia with review of literature.