• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2023.05a
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• pp.148-149
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• 2023

우리나라에서는 매년 2천여 건 이상의 해양사고가 발생하고 있으며, 정부는 해양사고의 발생 현황 및 원인분석을 통해 사고 저감을 위한 정책을 수립하고 있다. 중앙해양안전심판원에서는 '해양사고심판법'에 따라 해양사고의 원인을 조사하여 이를 재결서의 형태로 공개하고 있다. 이번 연구에서는 재결서의 원인판단 주제어를 기반으로 텍스트 마이닝을 수행하여 사고 종류별 해양사고 위험요인을 식별하였다. 도출된 키워드는 해양사고의 발생 원인과 밀접한 관계가 있는 키워드로 볼 수 있으므로, 해양사고의 원인분석 및 사고 예방대책 수립에 활용될 수 있을 것으로 전망된다.

• Resources Recycling
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• v.29 no.6
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• pp.27-34
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• 2020

In order to remove sulfate(SO42-) and purify the Li2CO3, dissolution and recrystallization of crude Li2CO3 using distilled water and HCl solution was performed. When Li2CO3 was dissolved using distilled water, the amount of dissolved Li2CO3(wt.%) increased as the solution temperature decrease and showed about 1.50 wt.% at 2.5℃. In addition, when Na2CO3 was added and the Li2CO3 solution was recrystallized, the recrystallization(%) increased with increasing temperature, resulting in a 49.00 % at 95 ℃. On the other hand, when Li2CO3 was dissolved using HCl solution, there was no effect of reaction temperature. As the concentration of HCl solution increased, the amount of dissolved Li2CO3(wt.%) increased, indicating 7.10 wt.% in 2.0 M HCl solution. When the LiCl solution was recrystallized by adding Na2CO3, it exhibited a recrystallization(%) of 86.10 % at a reaction temperature of 70 ℃, and showed a sulfate ion removal(%) of 96.50 % or more. Finally, more than 99.10 % of Na and more than 99.90 % of sulfate were removed from the recrystallized Li2CO3 powder through water washing, and purified Li2CO3 with a purity of 99.10 % could be recovered.

• Korean Journal of Materials Research
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• v.7 no.11
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• pp.942-950
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• 1997

NiAI기 산화물 분산강화(Oxide Dispersion Strengthende:ODS)합금을 기계적 합금화 (Mechanical Alloying: MA)방법으로 제조하였으며, 열간압축방법으로 성형하였다. 연이어 단순항온처리에 의한 정상결정립성장과 특성조건에서의 thermomechanical treatment 에 의한 이차재결정화를 유도하였다. 결정립 조대화된 ODSD MA NiAI의 creep 성질 및 이에 조대화된 미세조직은 creep 성질이 저하된 반면, 이차재결정화된 MA NiAI의 creep성질은 크게 향상되었다. 이 creep 성질의 향상은 이차재결정화의 특성인 급격한 결정립의 조대화, 분산상의 성장억제 및 grain aspect ratio의 증가에 기인한 것으로 사료되었다. 이차재결정화된 ODS MA NiAI의 creep또는 glide controlled dislocation creep임을 제시하지만, 전체 creep속도가 결정립 크기 및 grain aspect ratio의 영향을 크게 받은 것을 볼 때, 결정립계 미끄럼기구가 주 creep 기구와 조합되어 MA NiAI의 전체 creep기구에 영향을 준 것으로 추정할 수 있었다.

• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2006.05a
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• pp.221-224
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• 2006

이온주입으로 비정질화된 실리콘의 재결정화 및 활성화에 대한 실험을 전기로를 이용하여 수행하였다. 비정질 실리콘이 결정화 및 활성화가 이루어지면 전계효과 이동도가 좋아진다. 이동도가 향상되면 저항이 작아지고, 이로 인하여 소자의 크기가 작아질 수 있어 소형화가 가능해진다. 결정화 정도를 확인하는 방법으로 Four point probe를 이용한 면저항 측정과 라만 peak 측정을 이용하였다. 이온주입 후 비정질화된 실리콘의 재결정화를 통해서는 $600\;^{\circ}C$에서 1시간 열처리한 값이 가장 많이 결정화가 되었다는 것을 알 수 있었다.

• Product Safety
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• s.112
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• pp.42-43
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• 2003

• Korean Journal of Food Science and Technology
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• v.29 no.5
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• pp.939-946
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• 1997

Effects of moisture content on the gelatinization and recrystallization of non-waxy and waxy rice starch gels were investigated by differential scanning calorimetry (DSC). The recrystallization rates of the starch gels containing various moisture contents $(40{\sim}70%)$ were analyzed by Avrami equation. The waxy rice starch had higher gelatinization temperature and enthalpy than non-waxy one. The highest degrees of recrystallization in both rice starch gels stored at $4^{\circ}C$ were shown at 40%, and recrystallizations above 80% moisture content were not found. The degree of recrystallization of waxy one was higher than that of non-waxy one in the range of 40 to 60% moisture content. The Avrami exponents (n) of both rice starch gels were near to 1.0 and the time constant (1/k) was increased with increasing moisture content in the range of 40 to 70% moisture content. The recrystallization rate of waxy rice starch gel was slower than that of non-waxy one. The recrystallization of rice starch gels could be explained by the change of ice melting enthalpy during storage. The Wg's, represented the maximum practical amount of plasticizing water, were about 29.9% and 28.2% for non-waxy and waxy rice starch gels, respectively.

• Korean Architects
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• no.12 s.213
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• pp.58-61
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• 1986

• 전기의세계
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• v.46 no.4
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• pp.3-4
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• 1997

• Polymer(Korea)
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• v.27 no.6
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• pp.521-527
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• 2003

It was found that polypropylene shows rearrangement of crystal structure during the melting process. For the analysis of recrystallization behavior, the change of dynamic mechanical property, crystallinity, and crystal structure were studied by DSC, FT-IR, SAXS, and DMA. Melt-recrystallization-remelting behavior of iPP was clearly observed when iPP was cooled down kom the melt more rapidly. Elastic modulus of iPP increased during the recrystallization process but crystallinity of iPP shows constant value. Furthermore, the full width of half mean of SAXS pattern decreased about 30%, and intra-lamella ordering of iPP increased during the melt process but is was not found for sPP.

• Journal of the Korean Society of Marine Environment & Safety
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• v.30 no.1
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• pp.82-88
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• 2024

As the modern maritime industry rapidly progresses through technological advancements, data processing technology is emphasized as a key driver of this development. Natural language processing is a technology that enables machines to understand and process human language. Through this methodology, we aim to develop a model that predicts the proportions of outcomes when entering new written judgments by analyzing the rulings of the Marine Safety Tribunal and learning the cause-providing ratios of previously adjudicated ship collisions. The model calculated the cause-providing ratios of the accident using the navigation applied at the time of the accident and the weight of key keywords that affect the cause-providing ratios. Through this, the accuracy of the developed model could be analyzed, the practical applicability of the model could be reviewed, and it could be used to prevent the recurrence of collisions and resolve disputes between parties involved in marine accidents.