• Journal of Astronomy and Space Sciences
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• 제26권1호
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• pp.111-126
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• 2009

인공위성 궤도 결정을 위해 한국천문연구원의 0.6m 광시야 망원경을 이용하여 중 고궤도 인공위성과 폐기위성을 관측하였다. 관측 자료는 영상처리 및 좌표 보정을 통해 장착기기에 의한 오차를 보정한다. 위성 관측 사료에서 얻은 좌표 정보는 관측 시스템의 불안정성과 끝점 결정 오차에 의해 13각초의 오차를 가진다. KODAS의 결과로 얻은 시뮬레이션 좌표와 Gauss 방법을 이용해 예비궤도 결정을 수행하고 궤도 결정에 적합한 시간 간격을 찾아보았다. 또한 미분보정을 통한 예비궤도 결정 결과의 향상을 확인하였다. 이들 결과를 평균궤도요소 형대로 변환하여 실제 관측 자료와 비교하여 에비궤도 결정을 통해서 짧은 시간동안 위성의 추적이 가능함을 확인하였으며, 미분보정을 통해 그 결과를 향상시킬 수 있음을 확인하였다.

• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.106-120
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• 1991

The main purpose of this study was to investigate the possibility of obstruction of dentinal tubules through irradiation of the $CO_2$ laser on the dentin surface. For this study, 104 extracted caries - free premolars and molars were grinded their mesial or distal surface to expose dentin completly. And these specimens were divided into three Groups. Group I : those with their smear layer not removed and Group IT : those with their smear layer removed, were irradiated by the $CO_2$ laser(SPACE LASER - $CO_2$ VEGA 25) at five different energy levels ranging 4 - 20J/$cm^2$, and all specimens were observed with scanning eletron microscope (Hitachi S - 450). Group m was divided into 2 sub - groups: one with smear layer, another one without and those were irradiated with $CO_2$ laser of the same condition as Group I & II. All specimens were immersed in, $37^{\circ}C$, 0.5% methylene blue solution for 48 hours after 100 times of thermocycling at $4^{\circ}C$ and $60^{\circ}C$, and were observed with stereo -light microscope (Olympus SZH - ILLD) to evaluate dye penetration. The following results were obtained; 1. The dentinal tubules were obstructed through laser irradiation. 2. The dentinal tubules were still obstructed after treatment of 10% HCl/2sec., then it was proved that acid resistance of detin surface was also increased. 3. The Group of laser irradiation showed less dye penetration than control Group. 4. The smear layer hardly affected obstruction of the dentinal tubules through laser irradiation.

• Restorative Dentistry and Endodontics
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• 제16권1호
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• pp.200-208
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• 1991

The purpose of this study was to observe shear bond strength of composite resin to dentin following surface treatment. Freshly extracted forty-eight sound human molars were used in this study. They were stored at $4^{\circ}C$ physiologic saline solution before experiment. The teeth was then mounted with self curing acrylic resin in brass mold. The buccal surfaces of the teeth were grinding approximately 1.5mm by means of water-irrigated grinding wheel to expose the flattened fresh dentin surfaces. The specimens were divided into 6 groups according to preparation and treatment procedures on dentin surfaces; Group 1: Untreated after preparation with No.301 diamond point Group 2: Treated with primer for 60 seconds after preparation with No.301 diamond point Group 3: Untreated after preparation with No.700 fissure carbide bur Group 4: Treated with primer for 60 seconds after preparation with No.700 fissure carbide bur Group 5: Untreated after grinding with 600 grit silicon carbide paper Group 6: Treated with primer for 60 seconds after grinding with 600 grit silicon carbide paper Light cure dental adhesive was applicated to each specimen. Silux plus(3M) was inserted then into polyethylene tube of 3mm diameter and 3mm height, and polymerized to dentin surface. All of the specimens were stored in distilled water at $35.6^{\circ}C$ for 24 hours prior to testing. The shear bond strength was measured using an Instron Universal Testing Machine. The results obtained from this study were as follows: 1. The shear bond strength to dentin was the highest in group II. 2. The shear bond strength to dentin was the lowest in group III. 3. There was no significant difference in shear bond strength to dentin according to preparation instrument. 4. The primer treatment group showed significantly greater shear bond strength than untreated group.

• 복식문화연구
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• 제23권1호
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• pp.32-44
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• 2015

Increasing of Korean old women's rate is demographic characteristics attributed an aging society, silver generation would lead to silver fashion market with steady competitiveness and interest in fashion. So the study attempts to use foundation material for silver's fashion design by analyzing design characteristics and processing development of design representative women's top. Selecting brand for collecting photo using study represents a mid- and premium-priced with reference Brand Yearbook. After selecting brand on domestic and foreign I have collected picture from Internet shopping mall and web-site of fashion brand, from October 2013 to July 2014, but I selected 840 pictures based on front poses for easy decision. In order to search design characteristics according to sort of silver blouse design on domestic and foreign. I have examined shape, color, pattern, fabric sensation, inside composition line and decoration with reference standard of analysis in preceding research. Data analysis method was conducted on analysis of frequency and cross analysis using SPSS statistical package 21.0. The conclusion of design characteristic according to type of blouse design for silver, H-silhouette in shirt blouse seems to fit in body transformation and expose silhouette with correcting the body flaw. Using soft material in T-shirt blouse they are able to conceal a body defect and express beautiful silhouette. By using detail in pullover shirt blouse and tunic blouse for point of design, it express glamour and luxurious. Most of blouse are printed various pattern, it would looks more gorgeous using pattern.

• Journal of Radiation Protection and Research
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• 제41권4호
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• pp.378-383
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• 2016

Background: Radiation dose rates in PRIDE facility is evaluated quantitatively for assessing radiation safety of workers because of large amounts of depleted uranium being handled in PRIDE facility. Even if direct radiation from depleted uranium is very low and will not expose a worker to significant amounts of external radiation. Materials and Methods: ORIGEN-ARP code was used for calculating the neutron and gamma source term being generated from depleted uranium (DU), and the MCNP5 code was used for calculating the neutron and gamma fluxes and dose rates. Results and Discussion: The neutron and gamma fluxes and dose rates due to DU on spherical surface of 30 cm radius were calculated with the variation of DU mass and density. In this calculation, an imaginary case in which DU density is zero was added to check the self-shielding effect of DU. In this case, the DU sphere was modeled as a point. In case of DU mixed with molten salt of 50-250 g, the neutron and gamma fluxes were calculated respectively. It was found that the molten salt contents in DU had little effect on the neutron and the gamma fluxes. The neutron and the gamma fluxes, under the respective conditions of 1 and 5 kg mass of DU, and 5 and $19.1g{\cdot}cm^{-3}$ density of DU, were calculated with the molten salt (LiCl+KCl) of 50 g fixed, and compared with the source term. As the results, similar tendency was found in neutron and gamma fluxes with the variation of DU mass and density when compared with source spectra, except their magnitudes. Conclusion: In the case of the DU mass over 5 kg, the dose rate was shown to be higher than the environmental dose rate. From these results, it is concluded that if a worker would do an experiment with DU having over 5 kg of mass, the worker should be careful in order not to be exposed to the radiation.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.257-260
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• 2008

최근 초고층 건물 건설의 증가로 인해 많이 사용되고 있는 고강도 콘크리트가 화재 시 폭렬 현상으로 인해 내화성 문제가 대두되고 있다. 이에 본 연구는 화재 피해를 입은 폴리프로필렌 섬유(PP섬유) 혼입 고강도 RC 기둥의 비재하 가열 실험을 거친 시험체의 냉각 후 재하 실험을 통해 부재의 성능을 평가하였다. 화해 후 폭렬이 저감된 기둥의 성능 평가는 단면 손실이 없어 외관상 평가가 힘들기 때문에 잔존 내력을 추정하고 설계 단계에서 화해에 의한 성능 저하를 고려할 수 있는 기반을 만드는 것이 중요하다. 이에 범용 유한요소 해석프로그램인 DIANA(Displacement Analyzer)를 사용하여 부재를 해석하였고, 실제와 거동과 유사한 해석을 위해 온도 곡선은 재하 가열 실험의 온도 분표를 이용하여 단면 모델링에 적용하였다. 화재 노출 시간, 콘크리트 압축강도, 단면 치수를 변수로 적용하여 해석으로 도출된 화재 피해를 입은 고강도 RC 기둥의 P-M 상관곡선을 통해 잔존 성능을 평가하여 설계에 이용하도록 제시하였다.

• 한국콘크리트학회:학술대회논문집
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• 한국콘크리트학회 2008년도 춘계 학술발표회 제20권1호
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• pp.705-708
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• 2008

본 연구에서는 화재시 터널 콘크리트의 안전성 확보를 목적으로, 내화공법 변화에 따른 내화특성을 분석한 것으로서, 그 결과를 요약하면 다음과 같다. RABT온도가열곡선에 따른 내화특성으로, 플레인 콘크리트는 초기의 극심한 고온에 의해 심한 폭렬현상이 발생하였고, 내화공법변화에 따라서는, 유기섬유를 혼입하는 방식과 보드방식의 경우는 폭렬이 방지되는 것으로 나타났으며, 스프레이 방식의 경우는 보강재인 메탈라스가 뿜칠재와 같이 탈락되면서 열응력 등에 의해 구조체 콘크리트가 철근이 노출되는 등 100mm이상 깊이의 심한 폭렬이 발생하였다. RWS 온도가열곡선에 따른 내화특성으로, 유기섬유를 혼입한 경우는 콘크리트 표면이 약 5mm이내 깊이의 융해현상이 발생하였고, 스프레이 방식의 경우는 뿜칠재가 박리되어 구조체 콘크리트가 철근이 노출되는 등 100mm이상 깊이의 심한 폭렬이 발생하였으며, 보드방식의 경우도 보드가 고온에 융해되면서 구조체 콘크리트가 고온에 직접 노출되어 전면적으로 탈락현상이 발생하였는데, 이와같은 특고온 가열조건에서는 특별한 내화대책수립이 필요한 것으로 사료된다.

• 대한지리학회지
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• 제47권1호
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• pp.1-12
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• 2012

종족(宗族)과 월남민(越南民)의 아이덴티티로부터 확인되는 한국인의 특정한 집단적 정체성은 오랜 시간에 걸쳐 자연스럽게 형성된 것이 아니고 인위적으로 구성된 사회적 산물이다. 한국학을 지향하는 한국 인문지리학이 설정해야 할 목적 중 하나는 현대 한국인이 개인적으로나 집단적으로 공유하는 아이덴티티의 복합적이고도 경합적인 구성을 장소와의 관계 속에서 분석함으로써 보편적 한국인의 미래상, 즉 아이덴티티를 구체적으로 모색하는 것이다. 그러기 위해 한국 인문지리학은 아이덴티티, 장소, 이데올로기 또는 권력으로 구성되는 삼자 관계의 역동성, 지속성, 은밀성을 노출시키기 위하여 특정 장소를 연구의 출발점으로 삼을 필요가 있다. 그리고 이 때 한국 인문지리학이 지향해야 할 궁극적 목표는 전지구화의 시대에 적합한 장소 개념, 즉 외향적이고 진취적인 장소 의식을 한국인들에게 널리 전파시키는 것이다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1998년도 하계학술대회 논문집 G
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• pp.2541-2543
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• 1998

This paper describes the fabrication process to fabricate metallic structure of high aspect ratio using LlGA-like process. SU-8 is used as an electroplating mold. SU-8 is an epoxy-based photoresist, designed for ultrathick PR structure with single layer coating [1,2]. We can get more than $100{\mu}m$ thick layer by single coating with conventional spin coater, and applying multiple coating can make thicker layers. In the experiments, we used different kinds of SU-8, having different viscosity. To optimize the conditions for mold fabrication process, experiments are performed varying spinning time and speed, soft-bake, develop and PEB (Post Expose Bake) condition. With the optimized condition, minimum line and space of $3{\mu}m$ pattern with a thickness of $40{\mu}m$ and $4{\mu}m$ pattern with a thickness of $130{\mu}m$ were obtained. Using the patterned PR as a plating mold, metallic structure was fabricated by electroplating. We have fabricated a electroplated nickel comb actuator using SU-8 as plating mold. The thickness of PR mold is $45{\mu}m$ and that of plated nickel is$40{\mu}m$. Minimum line of the mold is $5{\mu}m$. Patterned metallic layer or polymer layer, which has selectivity with the structural plated metallic layer, can be used as sacrificial layer for fabrication of free-standing structure.

• 복식
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• 제63권6호
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• pp.69-83
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• 2013

This research is to analyze costumes of Greek Mythology Gods in films using Morris' semiotics. In film "Clash of The Titans", Zeus' costume of shining gold armored body suit and long manteaux expressed the limitless sublime. The definite form contouring body shape of his costume also demonstrated classical beauty. Hades' costume of dark colored armor, long manteaux, and transformation via smoke also described the limitless sublime. The unbalanced and irregular shaped armor showed ugliness. In "Percy Jackson & The Olympians: The Lightening Thief", the armor and long manteaux of Zeus showed the limitless sublime. The beauty of his body and his sophisticated business wear indicated classical beauty. These features were also present in Poseidon's costume as well. The limitless sublime and ugliness are implied in Hades' look by portraying him as having a monster body with horns and wings, and his costume of punk look. In "Immortals", gods of Olympus wore clothing that was reminiscent of Egyptian times, which represented a time of strong royal authority, in order to expose the limitless sublime. Classical beauty was shown in the beauty of their body. Titans' costumes and look of non-human being were composed of black and red to present ugliness. The inherent meanings of Gods' costumes are death of god, patriarchy, and the good triumphing over the evil. The Greek gods are not held in the same reverence in the contemporary society. However mythology inspires lots of visual creations. The results help to accumulate a creative design database for fashion.