• Korean Chemical Engineering Research
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• 제55권2호
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• pp.195-200
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• 2017

사고 대응 가이드라인은 사고 발생 시 그 영향을 줄이기 위한 수단으로 중요한 역할을 한다. 유용한 사고 대응 가이드라인의 개발을 위하여 개발 절차에 공학적 방법론의 적용이 필요하다. 본 논문에서는 기존에 존재하는 사고 대응 가이드라인 작성 방법론에 Bow-Tie 기법, 사고 전개 모델, 위험 대응 의사결정 등 위험 관리 기법을 적용하였다. 이러한 방법으로 일반화된 사고 대응 가이드라인 작성 절차를 제안하였으며, 직접적으로 활용할 수 있도록 Sheet를 개발하고, 특정 Case를 적용하여 Sample Guide를 작성하였다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2004년도 춘계학술대회 논문집 방전 플라즈마 유기절연재료 초전도 자성체연구회
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• pp.87-93
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• 2004

Laminated Polypropylene Paper (LPP) and Kraft paper were used as ac power insulation for conventional cable as well as high temperature superconducting (HTS) cable because of its prominent insulating characteristics. However, researches on the use of LPP/Kraft paper in HTS cables are thinly scattered. In this paper, the effect of laminate polypropylene paper on the breakdown strength of LPP/Kraft multi-layer sample impregnated with liquid nitrogen (LN2)under ac and impulse applied voltage was studied. In addition, the breakdown strength characteristics of LPP and Kraft multi-layer sample were also investigated. It was found from the experimental data that the LPP has higher breakdown strength value than Kraft paper in ac and impulse. Especially in the ac case, the breakdown strength increases as the component ratio of LPP in the LPP/Kraftsample increases and slightly affected by the inserting position of LPP but in impulse case, the breakdown strength strongly depends on the number of LPP and the relative position of LPP.

• 한국도로학회논문집
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• 제15권1호
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• pp.57-63
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• 2013

PURPOSES: This study is to investigate the Hot In-Place recycling asphalt mixture in Korea using field produced materials. METHODS: Hot In-Place reclaimed asphalt mixture was investigated to evaluate the mixture properties based on various test results such as Marshall Test, Indirect Tensile Test, TSR, and Wheel Tracking Test. These test values were compared with domestic standard specification. RESULTS: The result of the laboratory experiment indicates that the Hot In-Place Reclaimed(HIR) asphalt mixture produced at the field constrution site was satisfied all of the test criteria such as Indirect tensile test, Marshall and TSR test, and wheel tracking test. During the test, the research team found that current HIR system is required an extention of mixing time to improve quality and to reduce variation of sample to sample. Although the current HIR mixture was passed the test criteria, there is a potential capability to enhance the mixture properties as extend mixting time. CONCLUSIONS: Based on these laboratory test results, It would be concluded that domestic HIR mixture's properties were satisfied all standard specification related with evaluation of recycling asphalt mixtures. Based on this case study result, there is a chance to save construction cost and increase the usage of reclaimed asphalt concrete in the future.

• 한국화재소방학회논문지
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• 제23권3호
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• pp.17-22
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• 2009

에폭시 분체도료는 부스닥트, 및 전기기기에 절연재료로 광범위하게 사용되어 진다. 특히 Coating 절연 방식의 경우 전류에 의한 줄 열로 인해 전기화재 및 폭발의 점화 원인이 된다. 본 연구는 에폭시분체도료의 열화특성에 대해 절연파괴, 아크방전, 수명특성(V-t)을 중심으로 비교검토하고 이에 대한 기초데이터 확보 및 전기화재 원인인 절연특성에 대해 연구 하였다. 온도변화에 따른 절연특성은 시편 KS가 유리전이온도(Tg) 이전까지 $8{\sim}10%$ 정도의 감소로 안정적이었다. V-t 및 아크방전특성의 경우, 열화시편에서도 안정적 특성을 유지하였다. 열화에 의한 전기적특성의 경우 시편KS가 우수한 성능을 가지고 있다.

• 한국초전도ㆍ저온공학회논문지
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• 제24권3호
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• pp.30-34
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• 2022

Effects of electron beam (EB) irradiation on the mechanical strength of Cu (conducting sheath) and Nb (diffusion barrier) of Cu/Nb/MgB₂ superconducting was investigated. Wire- and tape-type Cu/Nb/MgB₂ samples were irradiated at E-beam energy of 2.5 MeV and 5 mA and a maximum E-beam dose was 5×10¹⁷ e/m². The hardness value of Cu and Nb region was measured by the Vickers micro-hardness method. In the case of the wire sample, the hardness of Cu and Nb increased proportionally as the dose was increased up to 5×10¹⁷ e/m², whereas in the case of the tape sample, the hardness increased up to a dose of 0.5×10¹⁷ e/m², and decreased slightly 5×10¹⁷ e/m². The hardness increase of Cu and Nb is believed to be due to the decrease of the deformability of Cu and Nb due to the defects formed inside the materials by E-beam irradiation.

• 한국초전도ㆍ저온공학회논문지
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• 제11권4호
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• pp.12-15
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• 2009

The $I_c$ degradation behavior of critical current in differently processed YBCO and SmBCO CC tapes with IBAD template has been investigated. It has been known that the residual strain in the CC tape will influence the shape of the $I_c$-strain window; $I_c$ may show a peak value if there exist a residual strain induced in the tape during manufacturing. The difference of residual strain may be resulted from the adopted different deposition techniques. In this study, bending test of CC tapes has been done using the Goldacker bending test rig which can produce both compressive and tensile bending strain continuously or alternately to the sample. For SmBCO CC tapes, in continuous compressive bending test, $I_c$ showed a minimal increase and did not degrade up to the largest strain that can be applied using the bending rig equivalent to 1.15% based on the sample thickness. However, in the case of alternate application of compressive and tensile bending strain, $I_c$ showed a larger degradation and a lower reversible limit when compared with the case of continuous application of the bending strain. When $I_c$ started to degrade significantly at the tension side, the reversibility ended, also at the compression side which is resulted from the permanent deformation like delamination or cracks that was induced due to tensile bending strain.

• 한국지진공학회논문집
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• 제28권1호
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• pp.67-75
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• 2024

In the case of the Pohang earthquake, which had a magnitude of 5.4 in 2017, geotechnical damages such as liquefaction and ground settlement occurred. The need for countermeasures has emerged, and experimental research in the Pohang area has continued. This study collected undisturbed samples from damaged fine-grained soil areas where ground settlement occurred in Pohang. Cyclic tri-axial tests for identifying the dynamic characteristics of soils were performed on the undisturbed samples, and the results were analyzed to determine the cause of ground settlement. As a result of the study, it was determined that in the case of fine-grained soils, ground settlement occurred because the seismic load as an external force was relatively more significant than the shear resistance of the very soft fine-grained soils, rather than due to an increase in excess pore water pressure.

• 한방재활의학과학회지
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• 제15권1호
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• pp.39-65
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• 2005

Objectives : This study was aimed to find out correlation of relation between cardiopulmonary function and body fat. Methods : We studied tendency of change of cardiopulmonary function and body fat for medication of Ephedrae Herba capsule by ergogenic aids with circuit training. We got the results for Exercise stress test and Segmental Bioelectrical Impedence Analysis. Results : 1. Sample Group of Ephedrae Herba medication and Circuit training generally showed the insignificant improvement of Body composition, but Control Group of Placebo and Circuit training significantly(p<.05) showed significant improvement of Body composition. 2. Sample Group of Ephedrae Herba medication and Circuit training generally showed the significant improvement of cardio-pulmonary function. Control Group of Placebo and Circuit training showed insignificant elevation of Cardiopulmonary function. 3. In the case of Sample Group, there wasn't closely correlation relationship of improvement of cardiopulmonary function and body composition, but in the case of Control Group, there was closely correlation relationship of improvement of cardiopulmonary function and body composition. Conclusions : It might be recognized that cardiopulmonary function has the correlation of body composition, and Ephedrae Herba might help the reduction of Body Fat by elevation of Cardiopulmonary function for ergogenic aids and it might be needed further study In various viewpoints.

• 공업화학
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• 제21권6호
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• pp.616-620
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• 2010

Liquid Crystal Display (LCD) 제조 공정에서 배출되는 폐유기용제에서 Propylene Glycol Monomethyl Ether Acetate (PGMEA)를 회수하여 재활용할 목적으로 다단계 증류탑을 이용하여 실험실적 규모의 증류 실험을 수행하여 최적 환류비를 결정하고자 하였다. 최종실험결과, 시료 A의 경우 PGMEA는 98% 이상, 수분 함량은 0.05% 이하이며, 시료 B의 경우 Reflux ratio를 6으로 한 경우 PGMEA 95% 이상, 수분 함량은 0.01% 이하이다(시료 A, B에 대한 내용은 Table 1에 명시함.). 이 값은 LCD 제조에 재활용할 수 있는 일반 수준인 90%보다 높은 수치로서 적용이 가능하다.

• Journal of the Korean Wood Science and Technology
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• 제10권3호
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• pp.168-179
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• 1982

The first step to utilize the growing resources of Italian poplar (Populus euramericana I-476) for pulp-Woods, its characteristics and adaptabilities to the pulp industry must be investigated completely. The plantation methods are important for its fast growing in stock, and no less important is the cutting age for its utilization as pulpwood. In this paper, the stone groundwood pulping, refiner groundwood pulping and chemi-groundwood pulping characteristics by the age of tree, along with their physical and chemical characterstics were tested, and relationships between the age groups were analyzed to find out the optimum felling age. The results obtained are as follows: 1. The coefficient of pliability was a little higher in the case of younger trees. 2. The water retention value of each pulp was directly proportional to its physical strength, but this tendency was not detected between the age groups of sample woods. 3. Generally, the physical strength of younger wood pulp was lower regardless of the pulping process. But in the case of pretreatment with NaOH, Asphund and CGP pulp from 5 year old sample wood were stronger in physical strengths than those of GP and Asplund pulp with no pretreatment from 10 years old sample wood. 4. The tear factor of Asplund pulp with alkali pretreatment was higher than that of CGP pulp but the breaking length and the burst factor was similar in all processes. Considering the pulp yield and its brightness, CGP process seems to be advantageous. 5. The dissimilarity of physical strength between 7 and 10 years old wood pulp was not very large in all pulping processes but the physical strength of 5 year old wood pulp was very weak. In the of groundwood pulping from Italian poplar woods, 5 year old wood pulp should be mixed with other long fiber pulp for making a good paper.