• 소성∙가공
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• 제14권1호
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• pp.43-48
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• 2005

The production of metal strip with uniform thickness and flatness are two important problems associated thin strip rolling. The thickness and flatness of strip are affected by the flattening of contact surface between strip and roll, the elastic recovery and the bending of roll. Especially, the flatness of the strip is greatly affected by bending deflection of roll. The roll must be designed considered the elastic deformation of roll. This study describes the measurement of thickness and flatness of strip and shows the crown roll for producing flat strip. But it is difficult to produce the crown roller. The cross rolling that is a simple method which can produce the flat strip is introduced and it is found the optimal cross angle for improvement of flatness of plate. These problems are solved by the MARC code on the basis of elastic-plastic material and the updated Lagrangian formulation.

• 대한기계학회논문집A
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• 제31권8호
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• pp.847-854
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• 2007

The battery electrode of a mobile phone is made of layered polymer coated on aluminum foils and the hot rolling process is applied to increase the density per volume of an electrode for a high capacity battery. The flatness of batteries surfaces should be less than $2{\mu}m$. To satisfy the required flatness, the deformation of roll surface due to bending and heating of the roll should be minimized. Complicated hot oil paths of $100^{\circ}C$ inside the roll are required for heating the polymer layers. FEA was used to calculate thermal deformations and temperatures distributions of the roller. Based on FEA, a modified surface curvature called a crown roll was suggested and this gave the area of 30% improved flatness compared with a flat roll. The flat roll satisfied the flatness of $2{\mu}m$ in the length of 340 mm and the crown roll resulted in the longer length of 460 mm. Experiments to measure the temperature distribution and thermal strain were performed and compared with FEA. There were only 6% difference between two results.

• 복식문화연구
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• 제8권3호
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• pp.486-492
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• 2000

This study is concerned with the jang il (　日). The purpose of this study was to trace the origin of jang il and to identify forms and the meaning of it. Significant findings and results of this research can be summerized as follows : It was found that jang il was a kind of brimmed hat with a round crown. People of Han Dynasty period wore jang il. It was favored by the people of Wei Chin (魏晉) Dynasty period of China and was a very popular hat in these periods. It was used by farmers and merchants. It was found that jang il was worn by a tribe of Kang(羌) in prehistorical period. It is considered that jang il of the Chinese, was derived from the people of Kang(羌). In the Tang and Five Dynasty periods women also wore jang il. Women from the upper class appeared used jang il. It appeared that Koguryoreans also used jang il : it was a kind of black wide brimmed hat with a round crown. which can be found in the tomb paintings of Yong Kang(龍崗). A horse rider wears jang il.

• 대한가정학회지
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• 제44권1호
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• pp.151-157
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• 2006

Ten types of male headgear-Kwonwoonkwan, crown-like headgear, hats with a square flap, hats with feathers, crowns with plumes, Ballip, hats with flat crowns, Somo, turban, and fur hats-were described in Jip-Sah, which was published in the 14th century. Mongolian people used summer headgear, winter hats, and crown ornaments, which had been used until the Ch'ing dynasty of China. From the late 12th century to 1304, the headgear styles remained the same, suggesting that the Mongolian people kept their tradition. Kwonwoonkwan, crown-like headgear, and Somo, presented in Jip-Sah, were also described in U. Yadamsuren's album, a pictorial depiction of the 20th century Mongolian headgear.

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제10권2호
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• pp.49-52
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• 2006

요즈음 디스플레이가 평판 제품인 PDP, LCD등으로 급속히 대체됨으로써 브라운관도 두께가 점점 얇아지고 있다. 따라서 새도우마스크 부품도 점점 평평해진다. 평평한 곡면은 진동이나 충격에 약하기 때문에 곡면을 크라운하게 설계하는 방법을 제시한다.

• 한국농림기상학회지
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• 제21권4호
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• pp.277-285
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• 2019

아고산 지역에서 지형은 바람과 일사, 토양수분함량 등에 영향을 주며 식물의 생장과 발달에 중요한 영향을 미친다. 아고산 지역에서 바람막이 지형이 가문비나무의 수관 생장에 미치는 영향을 알아보기 위해 서식지를 사면과 미지형에 따라 구분하고, 수고와 수관생장을 조사하였다. 아고산 지역의 가문비 나무는 서식지 내 바람의 영향과 미지형에 따라 수고 생장과 수관 생장이 다르게 나타났다. 바람맞이 사면에서 수고 생장과 수관생장률이 낮았고, 바람맞이 사면의 홀로 돋아져 바람과 같은 외부 환경에 노출된 미지형에서 자라는 나무는 바람의지 사면의 주변식생과 함께 자라는 나무보다 수관 생장이 절반 수준으로 낮았다. 바람의 영향이 강한 곳에서는 바람이 불어오는 방향으로 수관 생장이 억제되어 수관이 깃발형으로 발달하였다. 바람맞이 사면에서도 바람에 노출된 미지형 1 유형은 바람막이 역할을 하는 지피물이 존재하는 미지형 3 유형에 비해 수관의 기형이 심하였다. 본 연구는 바람이 심한 아고산 지역의 지형과 생장의 관계를 분석하여 가문비나무의 분포와 생장에서 바람막이 지형의 역할이 중요함을 보여주었다. 아고산 서식지 관리와 복원을 위해서 바람의 영향을 고려한 사면과 지형별 분포에 대한 분석이 필요하다.

• KSTLE International Journal
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• 제5권2호
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• pp.52-56
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• 2004

The hard disk drive performance depends strongly on air bearing characterisitcs of the head slider. The objective of the slider design is to provide accurate positioning of the magnetic read/write element at the very small height above the disk. Application of the numerical methods is required due to complexity of the air bearing surface of the slider. The Boundary-Fitted Coordinate System Divergence Formulation method can be used for calculation of pressure distribution in the case of steep film thickness gradients. In the present work, the interpolating functions used in the expression for the Couette flow are modified in order to improve the solution characteristics in the extremely high compressibility number region. The advantages of the modified method are demonstrated on example of the flat skewed slider. Finally, the modi.ed method is applied to analysis of the static characteristics of the femto-slider. The analysis results indicate the effect of the silder's air bearing surface crown on the flying height and the pitching angle in steady state position.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 한국자동제어학술회의논문집(국내학술편); 포항공과대학교, 포항; 24-26 Oct. 1996
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• pp.1068-1071
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• 1996

Good shape on flat rolled product is necessary to meet today's customer quality requirement. To meet the increasing demand in quality of strip shape from downstream customers, POSCO has replaced the Automatic Shape Control(ASC) system with the existing one that had used noncontact type measuring system at No.2 Cold Rolling Mill, Pohang works in October, 1995. The strip shape is influenced by the profile, roll crown, bending control, skew control system, as well as work roll cooling system. We have used ASC to adjust those factors in Cold Rolling Mill that could get a satisfactory result, almost less than .+-.5 1-unit deviation from the target shape. However, the downstream customer(i.e. Continuos Annealing Line) wants a good shape not only at the moment of exit of roll bite, but after rolling without tension. In this investigation, the difference will be discussed and how deal with this problem.

• 한국지역사회생활과학회지
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• 제21권1호
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• pp.5-12
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• 2010

The objective of this research was to examine the relationship between food preferences and personality of university students. The questionnaires were distributed to 198 university students in 2009. The data showed high correlation between personality and food preferences. According to the result of food preferences exams the most favorite food of university students was coffee, refreshing drinks, eggs, ice creams, bananas, porks, apples, chickens, weeds, grapes and food they dislike were sea cucumbers, livers, mung bean sprout, crown daisy, flat fishes, bean curd, green lavers, lotus roots, turban shells, egg plant etc. The correlation coefficient between food preferences and personality showed that male students had more dominance and sociability, and female students had more sociability and validity. On the other hand, a good diet group had higher responsibility and a poor diet group had higher sociability. Consequently, good food habits is essentially needed for the formation of desirable personality of students.

• Journal of Microbiology and Biotechnology
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• 제16권12호
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• pp.1968-1976
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• 2006

Recombinant E. coli ACV 1003 (recA:: lacZ) was used to measure low concentrations of DNA-damaging chemicals, which produce $\beta$-galactosidase via an SOS regulon system. Very low $\beta$-galactosidase activities of less than 0.01 unit/ml, $\beta$-galactosidase produced through an SOS response corresponding to the 10 ng/ml (ppb) of DNA damaging chemicals in the environment, can be rapidly determined by using an alternative interferometric biosensor with optically flat thin films of porous silicon rather than by the conventional time-consuming Miller's enzyme assay as well as the ELISA method. fu order to enhance the sensitivity in the interferometry, it needs to obtain more uniform distribution and higher biolinking efficiency, whereas interferometric sensing is rapid, cheap, and advantageous in high throughput by using a multiple-well-type chip. In this study, pore size adjusted to 60 nm for the target enzyme $\beta$-galactosidase to be bound on both walls of a Si pore and a calyx crown derivative was apllied as a more efficient biolinker. Furthermore, anti-$\beta$-galactosidase was previously functionalized with the biolinker for the target $\beta$-galactosidase to be specifically bound. When anti-$\beta$-galactosidase was bound to the calyx-crown derivative-linked surface, the effective optical thickness was found to be three times as high as that obtained without using anti-$\beta$-galactosidase. The resolution obtained was very similar to that afforded by the time-consuming ELISA method; however, the reproducibility was still unsatisfactory, below 1 unit $\beta$-galactosidase/ml, owing to the microscopic non-uniform distribution of the pores in the etched silicon surface.