• Journal of Korean Philosophical Society
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• v.139
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• pp.81-104
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• 2016

Given that the goal of study lies in the pursuit of truth and that philosophy asks questions about the origin of being, dealing with existence rather than essence is distant from the original meanings of philosophy. In spite of this, people talk about existence because it is closely related to the academic goals of phenomenology. It is true that phenomenology is Wesenswissenschaft ("the science of essences") in that it tries to restore the original nature of philosophy and establish philosophy as a strict science, but it cannot be ignored in phenomenological research that essence starts from existence. The purpose of this study is to examine the issues that traditional philosophy has sought after and missed by focusing on the issue of "existence." Existence is man's participation in the world, thus being expressed as being-to-the-world. All that has been perceived is understood in total unity and accordingly cannot be restored to ideological essence. In the end, the issue of existence should make a new start at the root of perception. Man is a thinking being and, at the same time, acting being. Here, an attempt to determine the priority between thinking and acting will be meaningless, indeed, and make an issue where there is none. Human beings will not thus stay at Descartes cogito argument' and try to go out into the world through the door opened by cogito. With these reasons in mind, this study examines the issue of existence with a focus on a phenomenal field and body.

• Proceedings of the Korea Crystallographic Association Conference
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• 2002.11a
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• pp.42-43
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• 2002

반도체 디바이스의 발전은 높은 직접화 및 동작 속도를 추구하고 있으며, 이를 위해서 MOSFET의 scale down시 발생되는 문제를 해결해야만 한다. 특히, Channel이 짧아짐으로써 발생하는 device의 열화현상으로 동작전압의 조절이 어려워 짐을 해결해야만 하며, gate oxide 두께를 줄임으로써 억제할 수 있다고 알려져 왔다. 현재, gate oxide으로 사용되고 있는 SiO2박막은 비정질로써 ～8.7 eV의 높은 band gap과 Si기판 위에서 성장이 용이하며 안정하다는 장점이 있으나, 두께가 1.6 nm 이하로 얇아질 경우 전자의 direct Tunneling에 의한 leakage current 증가와 gate impurity인 Boron의 channel로의 확산, 그리고 poly Si gate의 depletion effect[1,2] 등의 문제점으로 더 이상 사용할 수 없게 된다. 2001년 ITRS에 의하면 ASIC제품의 경우 2004년부터 0.9～l.4 nm 이하의 EOT가 요구된다고 발표하였다. 따라서, gate oxide의 물리적인 두께를 증가시켜 전자의 Tunneling을 억제하는 동시에 유전막에 걸리는 capacitance를 크게 할 수 있다는 측면에서 high-k 재료를 적용하기 위한 연구가 진행되고 있다[3]. High-k 재료로 가능성 있는 절연체들로는 A1₂O₃, Y₂O₃, CeO₂, Ta₂O, TiO₂, HfO₂, ZrO₂,STO 그리고 BST등이 있으며, 이들 재료 중 gate oxide에 적용하기 위해 크게 두 가지 측면에서 고려해야 하는데, 첫째, Si과 열역학적으로 안정하여 후속 열처리 공정에서 계면층 형성을 배제하여야 하며 둘째, 일반적으로 high-k 재료들은 유전상수에 반비례하는 band gap을 갖는 것으로 알려줘 있는데 이 Barrier Height에 지수적으로 의존하는 leakage current때문에 절연체의 band gap이 낮아서는 안 된다는 점이다. 최근 20이상의 유전상수와 ～5 eV 이상의 Band Gap을 가지며 Si기판과 열역학적으로 안정한 ZrO₂[4], HfiO₂[5]가 관심을 끌고 있다. HfO₂은 ～30의 고유전상수, ～5.7 eV의 높은 band gap, 실리콘 기판과의 열역학적 안전성 그리고 poly-Si와 호환성등의 장점으로 최근 많이 연구가 진행되고 있다. 또한, Hf은 SiO₂를 환원시켜 HfO₂가 될 수 있으며, 다른 silicide와 다르게 Hf silicide는 쉽게 산화될 수 있는 점이 보고되고 있다.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.10
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• pp.955-965
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• 2014

Transport phenomena of reactant and product are directly linked to intrinsic inhomogeneous random configurations of catalyst layer (CL) that consist of ionomer, carbon-supported catalyst (Pt/C), and pores. Hence, electrochemically active surface area (ECSA) of Pt/C is dominated by geometrical morphology of mass transport path. Undoubtedly these ECSAs are key factor of total fuel cell efficiency. In this study, non-deterministic micro-scale CLs were randomly generated by Monte Carlo method and implemented with the percolation process. To ensure valid inference about Pt/C catalyst utilization, 600 samples were chosen as the number of necessary samples with 95% confidence level. Statistic results of 600 samples generated under particular condition (20vol% Pt/C, 30vol% ionomer, 50vol% pore, and 20nm particle diameter) reveal only 18.2%~81.0% of Pt/C can construct ECSAs with mean value of 53.8%. This study indicates that the catalyst utilization in fuel cell CLs cannot be identical notwithstanding the same design condition.

• Applied Biological Chemistry
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• v.27
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• pp.29-46
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• 1984

To utilize several species of hard wood as raw materials of feed products, fermentation characteristics of cellulosic substrates to single cell protein was investigated, and results were summarized as follows. Among the microorganisms investigated, Tricoderma viride was selected as one of the most cellulolytic. Mixed culture of fungi did not show a synergistic effect on cellulose degradation. When the fungi were cultured at $28^{\circ}C$ for 7 days in a medium containing wheat bran 25 g, cellulose 0.25 g, proteose peptone 0.025 g and tween 800.025 g, cellulotic activities on carboxy methyl cellulose and filter paper reached maximum at 12 hr. The alkali treatment resulted in increased degradation of substrate from 13 to 18% when treated with enzymes for 12h, and reducing sugar formation increased with decreased size of substrates. Glucose was a very good feedback inhibitor of the enzyme from T.viride than that of xylose. When the substrate was rehydrolyzed, hydrolysis rate was 31% to reducing sugars within 12 hr. Quantative anlysis with HPLC showed the ratio of glucose to xylose in sugar syrups as 1.77 to 1. For the purpose of producing cellulosic-single cell protein from the sawdust of mulberry tree, 15 strains of xylose-assimilating yeast were isolated from 42 samples of rotten woods and compost soils and examined for their ability to utilize xylose. Then three strains were selected by their strong xylose-assimilating activities. The cultivative condition, the growth characteristics, and protein and nucleic acid productivities of three strains were investigated. The results obtained were, 1. Wood hydrolysate of mulberry tree was assimilated by 5 strains of CHS-2, CHS-3, ST-40, CHS-12 and CHS-13. 2. The optimum initial pH and temperature for the growth of strain CHS-13 were 4.4 and $30^{\circ}C$. 3. The specific growth rate of strain CHS-13 was $0.23h^{-1}$ and generation time was 3.01 hrs at the optimum condition. 4. CHS-13 strain assimilated 81 % of sugar in wood hydrolysate. 5. CHS-13 strain was identified as Candida guilliermondii var. guilliermondii 6. When the CHS-13 strain was cultured in the wood hydrolysate containing yeast extract, L-protein content was increased with yeast extract concentration. 7. The L-protein and nucleic acid yields from wood hydrolysate were 0.73 mg/ml and $4.92{\times}10^{-2}\;mg/ml$ respectively. 8. An optimal nucleic acid content of CHS-13 strain was observed in the medium containing 0.2% of yeast extract.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.772-777
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• 2003

선박이 배출하는 안정수(ballast water)는 외부로부터 유해 생물들이 유입되어 전파해 오는 주요경로로써 해양환경의 매우 중요하고 위험한 일종의 하나이지만, 이에 대한 효과적인 처리방법은 아직까지도 개발되지 못하였다. 그러나 최근 강 전리방전을 이용하여 고 밀집 산소와 물분자를 고농도 수산자유기(OH: hydroxyl radical)로 전리, 활성입자를 발생시켜 신속히 확산시키면 넓은 범위에서 비교적 낮은 농도로 유해성 침입 생물을 잔류물 없이 저렴한 비용으로 살균제나 촉매제의 사용 없이 소멸시켜 처리하는 효과적인 새로운 녹색방법을 제안하였다. 또한, 수산기는 강 산화제로써(산화환원 전위는 2.80 eV), 적조생물을 신속, 효과적으로 사멸시켜 잔유물과 오염물 발생 없이 이상적으로 해양적조현상을 처리할 수 있는 활성물질이다. 고출력 강 전리장치를 활용하면 수산기 활성제의 발생 농도를 Sr104 이상으로 얻을 수 있으므로, 해양적조처리에 요구되는 문턱 값 농도(~l$\times$$10^{-6}$)를 충족시킬 수 있으며, 이 경우 적조생물 소멸처리시간은 불과 10 sec 내외이므로 선박 안정수 처리문제와 함께 적조발생의 난문제를 해양동력학적으로 동시에 해결할 수 있는 효과적인 기술이다. 실험결과로부터 시간당 1 k톤의 활성물질을 발생하는 수산기활성제 제조장치의 경우, 약 4$\times$$10^2$ $\textrm{km}^2$/h의 적조해면을 처리할 수 있으며, 그 비용은 약 US$l,000 정도에 상당하므로, 적조에 따른 경제손실과는 비교될 수 없는 저렴하고 효과적인 방법이다. 활성물질의 생성시간과 가공시간은 불과 수십 $\mu\textrm{s}$ 및 수 sec 에 불과하므로, 1 kton/h 용량의 수산기활성제 제조장치의 환산소비동력은 약 200 kW이고, 장치의 체적은 10~30 ㎥의 공간으로 충분하므로, 소형선박으로 상당면적의 적조피해를 효과적으로 해결할 수 있다.

• The Korean Journal of Ecology
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• v.25 no.3 s.107
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• pp.139-144
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• 2002

Most of army depots contaminated with co-contaminants, 2,4,6-trinitrotoluene(TNT) and heavy metals. In phytoremediation for the TNT, heavy metals may inhibit mineralization, transformation and sequestration of TNT by the plant. We studied effect of cadmium on TNT degradation and transformation by Abutilion avicennae in hydroponic cultures. When cultured in 20 mgTNT/L and 1.3 mgCd/L, the plant displayed phytotoxicities; reduction of leaf fresh, leaf roil, chlorosis, leaf loss and fresh weight loss. Phytotoxicity was severer in the combined contaminants than in single contaminant. Because A. avicennae uptake just a little cadmium, 1.3 mgCd/L included in the TNT medium did not influece significantly TNT transformation, translocation and distribution by A. avicennae. Therefore, the soil solution containing cadmium would not affect TNT degradation by Abutilion avicennae in Army depots polluted with TNT.

• The Korean Journal of Ecology
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• v.25 no.2
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• pp.69-74
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• 2002

Most of army depots contaminated with co-contaminants. 2,4,6-trinitrotoluene(TNT) and heavy metais. In phytormediation for the TNT, heavy metals may inhibit mineralization, transformation and sequestration of TNT by the plant. W studied effect of cadmium on TNT degradation and transformation by Abutilion avicenneae in hydroponic cultures. When cultured in 20 ㎎TNT/L and 1.3 ㎎Cd/L. the plant displayed phytotoxicities; reduction of leaf fresh, leaf roll, chlorosis, leaf loss and fresh weight loss. Phytotoxicity was severer in the combined contaminnts than in single contaminant. Because A. avicennae uptake just a little cadmium, 1.3 ㎎Cd/L induded in the TNT medium did not influece significanfly TNT transformation, translocation and distrivution by A. Therefore, the soil solution containing cadmium would not affect TNT degradation by Abutilion avicennae in Amy depots polluted with TNT.

• The Korean Journal of Archival Studies
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• no.69
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• pp.153-187
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• 2021

Narrative runs through the entire human life. 'Narrative' is a means of understanding and experiencing human life. The past, the present and the future are not disconnected. The past is open to the future. The future defines the meaning of the past, and the past rreturn as the horizon of life. Past, present and future temporality functions as a Narrative. Records reproduce the past time as Narrative, and recount the past according to reading behavior. Reality and records complement each other with a cyclic and dialectic structure. This paper examines the relationship between reality and records. This paper applies Paul Ricoeur's Hermeneutics to records as a tool to examine the relationship between reality and record. We want to look at how records interpret and relates to reality, and how social justice of collective memory should be should be achieved against them.

• Applied Microscopy
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• v.41 no.1
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• pp.21-29
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• 2011

Balneotherapy has been widely used for the treatment of skin diseases in the world. The purpose of this study was to determine the bath effect of the alkaline reduced spring water with the properties of high pH and low oxidation reduction potential (ORP) on the skin injury induced by ultra violet (UV) irradiation. For this purpose, hairless mice were irradiated with UV-B to cause skin injury, and individually taken a bath in spring water (experimental group) and tap water (control group) once a day for 40 min during 21 days. We observed histological changes of the back skin through macro- and microscopic methods compared to the control group. We found that skin injury of the experimental group was more quickly recovered than that of the control group. Under the light microscope, the experimental group showed that epidermal thickening (p<0.01) and the mast cell activation (p<0.001) were lower compared with the control group, in addition infiltration of inflammatory cells and degranulation of mast cells were less observed. These results suggest that regular bath in the spring water with the properties of high pH and low ORP has a positive effect on the skin injury induced by UV irradiation.

• Food Science and Preservation
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• v.9 no.1
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• pp.51-55
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• 2002

Changes in food components of oyster mushroom Kimchi were investigated during storage at 20$^{\circ}C$. The pH of raw oyster mushroom Kimchi (ROMK) was higher than that of Chinese cabbage Kimchi (control) at initial stage, but it was lower than that of control after 1 day of storage. pH of blanched oyster mushroom Kimchi (BOMK) was slightly higher than that of controls The titratable acidity of oyster mushroom Kimchi was in inverse state to the pH. Amino acid nitrogen content of Kimchi tended to increase during storage, the content of ROMK was higher than that of control, the content of BOMK was not different from that of control. The reducing sugar content of Kimchi decreased significantly during storage, the content of ROMK was higher than that of controls the content of BOMK was slightly lower. The bacterial number of control increased rapidly at 2 days fermantation and reached plateau afterward. The number of ROMK tended to he alike that of control during storages the number of BOMK was fewer than that of control. On the taste panel of Kimchi after 1 day of storages ROMK obtained higher score than BOMK but the score was lower than control.