• Carbon letters
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• 제8권1호
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• pp.12-16
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• 2007

Molecular sieving carbon (MSC) for separating $O_2-N_2$ and $CO_2-CH_4$ has been prepared through chemical vapor deposition (CVD) of methane and benzene on activated carbon spheres (ACS) derived from polystyrene sulfonate beads. The validity of the material for assessment of molecular sieving behavior for $O_2-N_2$ and $CO_2-CH_4$ pair of gases was assessed by the kinetic adsorption of the corresponding gases at $25^{\circ}C$. It was observed that methane cracking on ACS lead to deposition of carbon mostly in whole length of pores rather than in pore entrance, resulting in a reduction in adsorption capacity. MSC showing good selectivity for $CO_2-CH_4$ and $O_2-N_2$ separation was obtained through benzene cracking on ACS with benzene entrantment of $0.40{\times}10^{-4}\;g/ml$ at cracking temperature of $725^{\circ}C$ for a period of 90 minutes resulting in a selectivity of 3.31:1.00 for $O_2-N_2$ and 8.00:1.00 for $CO_2-CH_4$ pair of gases respectively.

• Journal of Preventive Medicine and Public Health
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• 제54권5호
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• pp.376-379
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• 2021

Elemental mercury exposure can result in significant toxicity. Source decontamination and remediation are often required after larger elemental mercury exposures, but the details of these processes are infrequently reported. In the case described herein, a 64-year-old woman and her husband were exposed to elemental mercury in their home after the husband purchased it online for the purpose of recreational barometer calibration. After the mercury reportedly spilled during the calibration process, a vacuum cleaner was used to decontaminate the affected surface; this led to extensive mercury contamination of the home. The couple was relocated from the home while remediation occurred over the course of several weeks. Vacuum cleaning of an elemental mercury spill can lead to extensive volatilization and recirculation of mercury vapor. For smaller mercury spills, careful removal of visible mercury beads by using an eyedropper, cardboard, and masking tape is recommended. Larger spills require professional decontamination and remediation and may necessitate involvement of governmental resources. Vacuum cleaning should not be used as an initial method of decontamination after elemental mercury exposure. Careful attention to source decontamination can reduce the emotional and financial costs associated with extensive remediation after elemental mercury exposure.

• 환경영향평가
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• 제32권6호
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• pp.431-436
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• 2023

산업이 발전함에 따라 생태계로 유입되는 중금속의 양이 증가하고 있다. 중금속은 분해가 어려워 생태계 내에 장기간 잔류하고 독성을 유발한다. 이러한 중금속은 수처리 시 흡착, 여과, 화학적 침전 등 물리 화학적 방법으로 제거된다. 본 연구에서는 중금속 흡착 및 제거용 킬레이트 수지로 알긴산 비드를 선정하고 이에 따른 중금속 흡착효율을 평가하기 위하여 JEI (Jellyfish extract at immunity reaction)를 혼합하였다. JEI를 혼합한 비드는 알지네이트의 특성에 따라 납(79-99%)과 구리(64-70%)에서 높은 흡착효율을 보였으며 카드뮴(25-37%)과 아연(5-6%)에서 낮은 흡착효율을 나타내었다. 중금속 흡착은 JEI의 함량에 비례하여 증가하지 않았으나 50%와 100% JEI 비드가 유의미한 증가를 나타내었다. 반응 속도식을 적용한 결과 유사 1차 반응식보다 유사 2차 반응식에 더 적합한 것으로 나타났다. 결론적으로 비드의 생산 단가나 중금속 흡착제거 효율을 비교해보면 50% JEI 비드가 중금속 흡착제거에 적합한 것으로 사료된다.

• 한국식품과학회지
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• 제44권5호
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• pp.638-642
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• 2012

돼지축사에서 채집해온 6개의 육성돈의 분변에서 식중독 유발 바이러스인 HAV와 HEV를 검출하였으며, HAV는 88.3%의 검출율을 보였으며, HEV는 33.3%의 검출율을 보였다. 결과에는 제시하지 않았으나, 염기서열 분석결과 HEV는 사람에게 전염이 가능한 유전자형인 III형이었으며, 실험적으로 사람의 간세포인 PLC/PRF/5에 접종하였을 때 증식이 됨을 확인하였다. 식중독 유발 바이러스인 HAV와 HEV는 오염된 식품이나 물을 섭취하거나 교차 오염에 의해 전염이 가능하기 때문에 돼지축사에서 위생상태의 개선뿐만 아니라 육류를 섭취하기 전인 운송 및 가공과정까지 식중독 유발 바이러스에 의한 교차오염을 막는 노력이 필요하다. HAV와 HEV 모두 검출된 분변에서 HAV를 순수분리하고 빠르게 검출하기 위해 IMS-RT-PCR을 적용하였으며, 항원-항체 반응에 의해 순수하게 HAV만을 분리할 수 있었다. 또한 HAV만이 순수분리 되었는지 재확인하기위해 세포감염을 통해 증식된 바이러스를 확보한 후 nested RT-PCR을 수행한 결과, HAV만을 순수 분리할 수 있음을 확인하였다. 이는 IMS 활용기술이 단순히 항체를 교체함으로써 다른 특정 식중독 유발 바이러스의 다양한 시료에서 바이러스 순수분리 및 검출에 활용 가능성이 있음을 확인하였다.

• 패션비즈니스
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• 제2권1호
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• pp.25-34
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• 1998

This study has it's purpose in examining the materialized background. characteristic of African traditional costume and the A fro fashion of the year 1960. and it's influence on the contemporary fashion. Then the findings are applied to suggest a new way of image creation. 1960' s was the year in which people tried to free oneself from the ruling culture of the social standards. war. and the development of science. By such movement. people started to get interested in the environment and ecology. This then lead to the interest of the rights of the minority. With the youngs as the central figure A fro hair style and dashiki appeared as the street fashion. The characteristics of African costume applied to A fro fashion in 1990' s is as below. First. the North African style. Djellaba. and wrap style in the most common silhouette. Second. heavy materials such as stone. copper. silver. and gold are used. Necklace can be classified according to it's simple but. modern style. delicate but grand style. Bracelets are however. broad in width and many rings are worn widely. Third. Multi colored stripe and prints inspired by tattoo and deformation using red brown. dark beige. and orange are printed on textiles such as see through. Fourth. image of tattoo and deformation are applied to make-up. A fro hair and corn beads are also African taste. Fifth. African taste in recent fashion showed off the black beauty by appointing black models at the collection. In analyzing the study done above. characteristic images of African costume. accessaries and body painting was applied in presenting 3 creative designs. The first design named "Geometric I", took it's motif from the geometric pattern of the body painting with the afro hair. "Geometric II", the second design, showed it's application of geometric pattern of mutilation and the silhouette of the costume by using the see through. The third design called the "Geometric III" showed that the aesthetic and decorative side of clothing can be satisfied by applying various form and color of accessaries as the motif. A fro fashion is chosen as one of the folklore mood and it's beauty is conveyed on till today.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2009년도 춘계 학술발표회
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• pp.255-264
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• 2009

Soils containing vanishing materials lead changes in the microstructure of particulate media due to water inflow. Thus, dissolution renders some local unstability. As the moisture contents decease, the component of the vanished materials may affects on the cementation of paniculate materials. This cementation phenomenon has a huge influence on the stiffness, strength and stability under lower stress level. The goal of this study is to introduce the cementation effects on a compressional wave velocity, a shear wave velocity, and the resonant frequency of shear waves. The glass bead and salt water with different mole contents are used. Test results show that the changes of shear and compressional wave velocities consist of three stages. In the first region, compressional wave velocities increase and shear wave velocities decrease with a decreases in reducing water contents from 100% to 90~95%. In the second region, shear and compressional wave velocities become stable at 90~95% to 10% of the water contents. In the third region, shear and compressional wave velocities increases dramatically with a decrease in the water content due to the capillary force and cementation of salt. Furthermore, the resonant frequency of the shear waves shows similar phenomenon. Specimens prepared by glass beads and salt water are proved to be able to provide a meaningful insight in under structural behaviors of the cementation.

• 공학교육연구
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• 제21권2호
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• pp.39-50
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• 2018

In the 4th industrial revolution, the maker movement is spreading around the world with the fusion of advanced technology with product manufacturing. Already in developed countries such as the US and Japan, the emphasis is on maker education that integrates education into traditional makers' movement. Through this, we are fostering young talents who will lead the fourth industrial revolution era. Domestic maker education is mainly performed in the maker space, and is limited to the IT field using Arduino and App-Inventor. Therefore, it has the limitation of fostering IT-oriented makers. Therefore, it is affecting the proliferation of the maker's movement because of the difficulty of participation of the general public. The purpose of this study was to understand the characteristics of maker 's movement and to suggest the direction of Korean maker education. In order to accomplish the purpose of research, we analyzed the case of convergent maker education at D Creation Economic Innovation Center, which combines IT and culture technology. We conducted a case study on maker education(VR production project, electronic publishing, beads craft, leather craft, IoT) which was held from July 8 to August 30, 2017 five times. We conducted interviews with five preliminary makers who participated in all the courses of the education, and five instructors who acted as professional makers with pre- developed questionnaires. The results of the study were derived by applying the Thematic Analysis method after opening the contents of the interview. Based on the results of the study, we could suggest characteristics of Korean makers and future direction of maker education.

• Clinics in Shoulder and Elbow
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• 제15권1호
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• pp.37-42
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• 2012

목적: 총상에 의한 상완골 골절 증례를 통해 치료의 원칙에 대하여 고찰한다. 대상 및 방법: 28세 남자가 좌측 상완부의 총상으로 수상 후 5일에 응급실로 내원하였다. 상지의 신경 및 혈관 손상의 징후 및 타장기의 손상은 없었으며, 생체징후는 안정적이었다. 수상 당시 타 병원에서 총상에 대한 변연 절제술 및 세척술 후에 일차적 봉합술을 시행받았으며, 상완부의 전외측에 5 cm 가량의 오염된 상처가 있었다. 본원에서 변연절제술 및 탄환 파편의 제거술을 시행하고 외고정을 통하여 해부학적 정렬을 유지하였다. 술 후 8일까지 상처에 대한 무균적 소독을 시행하였으며, 정맥 항생제를 유지하였다. 술 후 9일째에 광범위 변연 절제술 및 항생제를 섞은 시멘트 구슬 삽입술을 시행하였다. 감염이 호전되는 소견을 보여, 시멘트 구슬 삽입 2주째에 외고정 장치를 제거하고 외고정 핀 삽입부의 피부 봉합술을 시행하였다. 1주 후에, 금속판을 이용하여 내고정을 하였다. 결과: 유합술 후 3 개월째, 만족스러운 상완골의 정렬과 골 유합을 얻었다.