實存 哲學의 時間 構造

李載萬 명지대학교 1968 明大論文集 Vol.1 No.-

This thesis has it her purpose to deal with the problem how a man understands the existence itself thru the “time of living” and with the problem how this existential man may deal with the structure of time. The ‘time’ is an essential factor for comprehending the existential element of a realistic man to have got a significant place in philosophy. The theme has been thoroughly pursued by the existential philosophy. The ‘time’ put back toward the internal consciousness of a man from the concept of an objective stream has come to be given a big step forward. As the time is experienced, future acts upon the present and past is construed as restricting a present action by serving the basis which supports the present, in consequence the existential philosophy has by necessity come to give a central place to the time. And as time is given to mann as an experience, the form is categorized into two, i.e. an objective time and a concrete, subjective time. And in accordance as the class of the time experience differs the difference of the time-sense also comes into being. Viewed from the construction of the time, the life philosophy and the existential philosophy have got something in common, which is brought to light by clearing the time structure of a man. 3 forms of the time-structure are; past… present… future. Then the present does not serve a trimming section between past the future… no, time is not such a body which may be trimmed at will. But a moment has width and flexibility to serve a chain. Future serves a plan and a hope. As a man does everything at any present moment, an element of future is included to assert itself and past is also included as a reminder and the present moment has got a very complex structure the present is not a momentary and transitory instant but a chain which binds what is at present with what was and what will be together. But the existential time which comprehends a man in finiteness may be termed as an expression of the human finiteness. Past at the present moment restricts the freedom of a human behavior and heavily burdening him asserts itself to press on the present. And a man who is put in a situation tries to overcome it with a relationship to the future, by these attempts a human nature comes into being. A man concentrates his whole attempts on the existential moment, and it is whether he may transcend ove the situation towards the future or he must escape from the situation faced, that is, he must deal negatively what is pressing on him. At this point, the existential, original time differs from the present-existing, non-original time. Real existence is absolute at the moment of this original time, but by jumping over, it breaks the barrier of time which flows to vanish. At this moment the real existence itself has got no longer the quality of time, but exhibits absoluteness. In other words another dimension which does not pertain to time-prolongation opens before us. Thus, in accordance with a constuction of the moment as a joint-spot between time and eternity, they try to grasp the absoluteness of a particular moment.

수치모형을 이용한 사행수로의 하상특성 분석

김이현,이만석 경복대학 2004 京福論叢 Vol.8 No.-

지구촌 곳곳에서 최근의 기상이변으로 인한 수해를 방지하기 위한 많은 대책들이 나오고 있다. 그 중 국지적인 호우로 인하여 국내의 많은 하천들의 사행수로 구간에서 편수위 및 홍수위 상승에 따른 피해가 심각하여 이에 대한 연구가 증가하고 있다. 본 연구에서는 사행수로의 하상특성을 분석하기 위하여 기본적인 수치모형 방정식의 이해와 이를 바탕으로 한 최근 국내의 사례를 예로 들었다. 수치 모형으로는 현장에서 범용되고 있는 것을 채택하되, 1차원 모형으로는 HEC-RAS를 2차원 모형으로는 RMA-2모형을 이용하였다. 분석 결과 유속의 경우는 2가지 모형 공히 사행구간의 변화를 알 수 있었으나, 수위는 1차원 모형 자체의 한계성이 나타났다. 사행 구간에서는 홍수시 만곡부 외측으로의 편수위 상승과 같은 외수의 월류로 인한 위험을 가중시키는 현상이 발생하게 되므로 제반계획의 수립시 이러한 사항을 충분히 고려하여야 한다. In every globe village, numerous methods appear for detection flood damage caused by unusual change of wether lately. Due to local storm, in nationwide meandering rivers disaster of increased superelevation and flood level is seriously. In this study, for analysis bed state in meandering channel the basic numerical model equation be understand and introduced an example domestic case. In numerical models, selecting used in field adopted HEC-RAS for one-dimensional model and RMA-2 for two-dimensional model. Results of analysis, case of flow velocity recognized variation of meandering channel in two computational models, but in case of water level we find out one-dimensional model's limitations. Occasion of flood, in outside section of meandering bend, because of added overflow existing state like increasing of superelevation is occurrence, in making various plan enough consideration is needed.

낭성법랑모세포종, 함치성낭, 치성각화낭의 방사선소견과 Ki-67, PCNA, Cytokeratin 발현과의 연관성에 관한 연구

송만용,이삼선,이진구,이원진,허민석,이재일,민병무,최순철 대한구강악안면방사선학회 2004 Imaging Science in Dentistry Vol.34 No.2

Purpose : To compare the proliferation potential of the epithelial cells between unicystic ameloblastoma (UA), dentigerous cyst (DC), and odontogenic keratocyst (OKC) and to correlate this proliferation potential with the radiographic features of these three pathoses. Materials and Methods : Immunohistochemical expression of PCNA, Ki-67, and cytokeratin as a proliferation marker were assessed for 15 cases of UA, 15 cases of DC, and 15 cases of OKC. The degree of immunochemical expression of three proliferation markers were correlated with the radiographic features, especially cortical expansion (negative and positive) and shape of border (scalloped and round). Results : Using PCNA and Ki-67, OKC showed the highest proliferation potential and UA the lowest. Statistically significant differences were found between the OKC and the UA (p.0.05). However, no statistically significant difference was present according to the radiographic features in all pathoses. Using cytokeratin, there was no significant differences of proliferation potential among three pathoses. Conclusions : OKC epithelium has the most intense proliferation potential, followed by the dentigeous cyst and then unicystic ameloblastoma. There is no significant relation between the radiographic features and the proliferation potential of epithelium of these three pathoses.

600합금의 미세조직 변화 및 SCC거동에 미치는 Ce 첨가의 영향

권오철,이용선,임연수,정만교,김정수 대한금속재료학회 2005 대한금속·재료학회지 Vol.43 No.1

High purity model alloys with major composition Ni-15Cr-9Fe-0.03C (600CEO) and Ni-15Cr-9Fe-0.03C-0.04Ce (600CE4) were produced. Using these model alloys the effect of alloying element Ce on the SCC behavior of Alloy 600 was evaluated in a caustic solution. To obtain carbides precipitated on grain boundaries, the thermal treatment was performed on both the solution annealed model alloys. Microstructural examinations using SEM and TEM EDX showed that the same structural carbides, Cr_(7)Cc₃, were precipitated on both the alloys and no significant difference in the amount of Cr depletion along grain boundaries was observed between the two model alloys. However, it was shown that the coverage of grain boundary carbides was higher in the Ce-bearing alloy (600CE4). The SCC susceptibility of the alloys was investigated in 40%NaOH solution at 315℃. Being evaluated in terms of the maximum crack depth, the SCC susceptibility of the alloy turned out to be reduced by the addition of Ce. The increased resistance to the SCC in the alloy 600CE4 was considered to be attributable to the increased coverage of grain boundary carbides. (Received September 30, 2004)

효소 단백 가수분해물의 항균 활성

주정현,이상덕,이정옥,오만진,이기춘 충남대학교 농업과학연구소 2002 농업과학연구 Vol.29 No.2

밀 단백질에 효소가수분해 할 때 생산되는 peptide의 항균활성과 천연항균제로서의 이용가능성을 검토하기 위하여 실험을 행하였다. 밀 단백질에 7종의 단백질가수분해효소를 작용시켜 생성된 가수분해물의 항균활성을 측정하고 한외여과, membrane filtration, HPLC를 이용하여 항균성peptide를 분리 정제한 후 분자량과 아미노산 결합 순서를 측정한 결과는 다음과 같다. 밀 단백질에 7종의 단백질 분해효소를 적용시켜 제조한 가수분해물중 Asp. saito protease를 적용시켜 얻어진 peptide 만이 항균활성을 나타내었다. Asp. saito protease는 37 ℃, pH 6.0에서 작용시킨 경우에 항균활성이 가장 높았으며, 50℃ 이상에서는 활성을 나타내지 않았다. 밀단백 효소가수분해물은 membrane filtration 에 의하여 분자량 1.000~3.000에서 항균활성이 나타났다. Membrane filtration으로 얻어진 항균활성분획을 HPLC로 분리한 결과 retention time 31.1~31.8 min에서 항균활성을 나타내었다. 밀단백 효소가수분해물은 121℃에서 15분간 가열하여도 효소활성이 유지되는 매우 안정한 화합물이었다. 항균활성분획을 MALDI-mass로 질량을 분석한 결과 1.633이었다. 항균성 peptide의 아미노산 결합순서는 cysteine, glycine, prolin, prolin, polin, valine, valine, alanine, alanine, arginine의 순서였다. This study was carried out to investigate whether peptide produced from wheat protein by enzyme hydrolysis can be used as a natural antimicrobial agent. Antimicrobial peptide was obtained form wheat protein by protease of 7 species. The produced antimicrobial peptide was purified through ultrafiltration membrane filtration and HPLC, and molecular weight and amino and sequence of the purified antimicrobial peptide were determined. Among hydrolysate produced from wheat protein by protease of 7 species, antimicrobial activity was observed for the peptide obtained from Asp. satio protease. The Asp. satio protease did production antimicrobial hydrolysate showing the highest antimicrobial activity at reaction condition of 37℃ and pH 6.0, but not at reaction condition above 50℃. Wheat protein hydrolysate was fractionated by membrane filtration and showed antimicrobial activity between molecular weight 1,000 - 3,000. The antimicrobial activity fraction obtained by membrane filtration was separated through HPLC and showed antimicrobial activity in the peak of retention time 31.1 - 31.8 min. Since after wheat protein protease hydrolysate was heated during 15 min at 121℃, antimicrobial activity was maintained we could be conviction as heat-stable peptide. Molecular weight of antimicrobial peptide identified by MALDI-mass was 1,633. Amino acid sequence of antimicrobial peptide was cysteine, glycine, prolin, prolin, prolin, valine, valine, alanine, alanine and arginine.

다결정 실리콘 태양전지의 상부 전극용 금속 박막 적용

김상수,임동건,이준신,심경석,김홍우,이만근 성균관대학교 1997 학술회의지원논문목록집 Vol.1997 No.-

We investigated grain boundary effect for terrestrial applications of solar cells with low cost, large area, and high efficiency. Grain boundaries are known as potential barriers and recombination centers for the photo generated charge carriers, which make it difficult to achieve a high efficiency cell. To reduce these effects of grain boundarues, we investigated various influencing factors such as thermal treatments various grid patterns selective wet etchings for grain boundarues, buried contact metallizations along grain boundaries, and use of metallic thin films. From the various grid patterns we learned that the series resistance of solar cell reduced open circuit voltage and consequently decreased the cell efficiency. This paper describes the effect of various grid patterns and the employment of metallic thin films for a top electrode.

만곡수로에서 교각으로 인한 수위변화 해석

차영기,김이현,이만석 단국대학교 신소재기술연구소 2000 신소재 Vol.9 No.-

본 연구는 만곡수로에서의 교각과 유량변화데 따른 수이변화의 특성을 실험으로 고찰한 것이다. 고정상과 이동상의 경우에 교각으로 인한 배수위 상승의 크기와 영향을 비교ㆍ분석함으로서 최대 상승량을 일으키는 지점의 변화와 그 원인을 알아보았다. 만곡부에서 교각 수와 그 크기를 달리하고, 그에 따른 배수위 상승 영향을 알아보았다. 만곡수로의 흐름을 관찰한 결과 최대 수위를 나타내는 지점은 고정상과 이동상에서 각각 단면 19와 단면 10에서 나타났고, 편수위 상승은 고정상에서 단면 6에서 최대이고, 이동상에서는 단면 9에서 최대로 나타났다. 유량 변화에 따른 최대 배수위 상승량은 평균적으로 고정상에서는 교각 설치 단면의 상류 첫 번째 단면에서, 이동상에서는 교각 설치단면의 상류 세 번째 단면에서 발생하였다. 또한 유량 변화량의 평균값인 1400CMS 유량으로 반복 실험한 결과 유수단면적을 달리할 때, 즉 교각 수와 교각 지름의 변화에 따라 고정상에서는 교각 설치 단면의 상류 세 번째 단면에서, 이동상에서는 교각 설치 단면에서 최대 배수위 상승이 발생하였다. This paper investigate the characteristics of water surface level due to piers and due to varying discharge in a curved channel by experiment. It is compared and analyzed the amount and effect of backwater due to piers, and the variation of the highest backwater points in a fixed bed and a movable bed respectively. And the variation of flow varying numbers and diameter of the pier at the bending part. The highest stage in a curved channel is showed at the section of 19 and 10 in the cases of a fixed bed and a movable bed respectively. The largest superelevations at a fixed bed and a movable bed are showed at the section of 6 and 9 respectively. The highest backwater stage due to varying discharge at a fixed bed is brought out at the first upsteam section of pier setting, and at he case of a movable bed it was the third upstream section of pier setting. Also, the highest backwater stage is brought out at the third upstream section of pier setting in a fixed bed, and at section of pier setting in a movable bed at the case of varying the pier numbers and diameter for 1,400CMS.

紅景天(Rhodiola sachlinensis)에서 항균성 물질의 분리 및 동정

심창주,이규희,정재홍,이상덕,김영호,오만진 한국식품저장유통학회 ( 구 한국농산물저장유통학회 ) 2004 한국식품저장유통학회지 Vol.11 No.1

홍경천의 천연 보존료로서의이용성을 검토하기 위하여 각종 용매로 홍경천 추출물을 제조하고 극성에 따라 순차분획, silica-gel chromatography, thin-layer chromatography, high perfomance liquid chromatography의 분리과정을 거쳐 순수 분리된 각 물질을 GC/MS(EI) spectrum, ¹H-NMR spectrum, ¹³C-NMR spectrum을 이용하여 항균물질을 동정하여 다음과 같은 결과를 얻었다. 홍경천에 대해 acetone, ethyl acetate, ethanol, methanol, chloroform, water의 각 용매로 추출한 결과 항균성분의 추출 용매로는 methanol이 가장 우수하였다. 홍경천 methanol 추출물을 n-hexane, chloroform, ethyl ether, ethyl acetate, n-butyl alcohol로 분획한 결과 ethyl acetate와 n-butyl alcohol 분획에서 우수한 항균력을 나타내었다. 홍경천 methanol 추출물은 그람양성 4균주와 그람음성 4균주에 대해 고체 배지의 경우 대체로 500 μg/mL에서 최소저해를 나타냈으며, 액체배지의 경우 100 μg/mL 내외에서 최소저해를 나타내었다.] Silica gel column chromatography에서 용매의 배율을 높여가며 용출한 결과 chloroform : methanol(8:2, v/v)의 비율에서 항균력이 가장 높게 나타났다. 분리된 항균성분을 silica-gel TLC plate에 용매의 비율을 높여가며 전개시켜 chloroform : methanol(9:1, v/v)에서 9개의 물질군을 얻을 수 있었으며, 그 중 항균력이 확인된 3개의 물질군을 HPLC와 NMR spectrum을 분석한 결과 gallic acid, (-)-epicatechin 및 kaempferol로 동정되었다. gallic acid, (-)-epicatechin 및 kaempferol의 항균물질 각각의 최소저해농도는 Staphylococcus aureus와 Listeria monocytogenes에 대해 gallic acid와 kaempferol 이 500 μg/mL, (-)-epicatechin이 100 μg/mL에서 저해를 나타내었다. The antimicrobial substances from Rhodiola sachalinensis were extracted, isolated and identified. The highest level of antimicrobial activity and its yield were obtained in methanol extract. The minimum inhibition concentrations of the methanol extract were 500 μg/mL on agar plate and 100 μg/mL in broth media for four gram positive and four gram negative microbials. The methanol extract was fractionated by n-hexane, chloroform, ethyl ether, ethyl acetate, and butanol, orderly. The separate was developed on the TLC plate with different solvent system ratio of chloroform and methanol. Nine substances were isolated from chloroform and methanol mixture(9:1, v/v). Among them, three isolates showed antimicrobial activity. Three substances separated by HPLC were identified by GC/MS(EI) spectrum and ^(1)H, ^(13)C-NMR spcetrum. They were gallic acid, (-)-epicatechin and kaempferol. The antimicrobial activites of each substances were shown gallic acid, (-)-epicatechin, kaempferol, orderly.

소 수정란의 공배양 및 동결이 체외발생에 미치는 영향에 관한 연구

이종진,이명헌,남윤이,이만휘,이봉구,김상근 충남대학교 수의과대학 동물의과학연구소 1996 動物醫科學硏究誌 Vol.4 No.-

The studies on the carried out to investigate the effects of co-culture with cumulus cells and oviduct epithelial cells on the in vitro fertilization and cleavage rate of bovine follicular oocytes, and to determine the optimum thawing temperature and equilibration time of frozen bovine embryos and on survival rate and in vitro developmental rate of bovine embryos. The ovaries were obtained from slaughtered Korean native cows. The follicular oocytes were cultured in TCM-199 medium containing 10 IU/㎖의 PMSG(Sigma, USA), 10 IU/㎖의 hCG, 1 ㎍/㎖의 β-estradiol(Sigma, USA) and 10% FCS(Sigma, USA) for 24-48 hrs in incubator with 5% CO_2 in air at 38.5℃ and then matured oocytes were again cultured for 12-18 hrs with motile capacitated sperm by preincubation of heparin. The bovine embryos following dehydration by cryoprotective agents and a various concentrations of sucrose were directly plunged into liquid nitrogen and thawed in 30℃ water. The results are summarized as followes : 1. The in vitro fertilization and in vitro developmental rates of bovine oocytes co-cultured with cumulus cells in TCM-199 media were 75.0%-76.8% and 17.3%-27.6%, respectively. And in-vitro fertilization rates of cumulus-enclosed oocytes(55.4%) were significantly(p<0.05) higher than cumulus-denuded oocytes(23.1%). 2. The in vitro fertilization and in vitro developmental rates of bovine oocytes co-cultured with 1 ×10^4 cells/㎖, 1 ×10^6 cells/㎖, 1 ×10^8 cells/㎖ and 1 ×10^15 cells/㎖ oviduct epithelial cells in TCM-199 media were 74.5%-77.8% and 15.7%-21.2%, respectively. 3. The in-vitro fertilization and in vitro developmental rates of bovine oocytes co-cultured in TCM-199 media containing PMSG, hCG, PMSG + hCG, PMSG + β-estradiol, hCG + β-estradiol 0 to 40 hrs after insemination were 74.0%-77.4% and 18.9% - 23.1, respectively. 4. The survival rates of bovine embryos thawed after rapid freezing in the media containing various kinds of cryoprotective agents added 0.25M and 0.50M sucrose were 14.7% - 35.1% and 17.6% - 31.6%, respectively. The survival rates of bovine embryos thawed after rapid freezing in the freezing media containing a various concentration of sucrose added 1.5M and 2.0M glycerol, 1.5M and 2.0M DMSO, and 1.5M and 2.0M propanediol were 23.5% -31.4% and 20.6% - 34.1%, respectively. 5. The temperature thawed at 30℃ after rapid freezing of bovine embryos resulted in a significantly higher embryos survival rate than did at 20℃ and 35℃. 6. The equilibration time on the survival rates of bovine embryos was attained after short period of time(2.5-5 min.) in the freezing medium higher than ling period of time(10-20min.).

The Influence of Reconstruction Algorithm and Heart Rate on Coronary Artery Image Quality and Stenosis Detection at 64-Detector Cardiac CT

Yi-Ting Wang,Chung-Yi Yang,Jong-Kai Hsiao,Hon-Man Liu,Wen-Jen Lee,Yun Shen 대한영상의학회 2009 Korean Journal of Radiology Vol.10 No.3

Objective: We wanted to evaluate the impact of two reconstruction algorithms (halfscan and multisector) on the image quality and the accuracy of measuring the severity of coronary stenoses by using a pulsating cardiac phantom with different heart rates (HRs). Materials and Methods: Simulated coronary arteries with different stenotic severities (25, 50, 75%) and different luminal diameters (3, 4, 5 mm) were scanned with a fixed pitch of 0.16 and a 0.35 second gantry rotation time on a 64-slice multidetector CT. Both reconstruction algorithms (halfscan and multisector) were applied to HRs of 40-120 beats per minute (bpm) at 10 bpm intervals. Three experienced radiologists visually assessed the image quality and they manually measured the stenotic severity. Results: Fewer measurement errors occurred with multisector reconstruction (p = 0.05), a slower HR (p < 0.001) and a larger luminal diameter (p = 0.014); measurement errors were not related with the observers or the stenotic severity. There was no significant difference in measurements as for the reconstruction algorithms below an HR of 70 bpm. More nonassessable segments were visualized with halfscan reconstruction (p = 0.004) and higher HRs (p < 0.001). Halfscan reconstruction had better quality scores when the HR was below 60 bpm, while multisector reconstruction had better quality scores when the HR was above 90 bpm. For the HRs between 60 and 90 bpm, both reconstruction modes had similar quality scores. With excluding the nonassessable segments, both reconstruction algorithms achieved a similar mean measured stenotic severity and similar standard deviations. Conclusion: At a higher HR (above 90 bpm), multisector reconstruction had better temporal resolution, fewer nonassessable segments, better quality scores and better accuracy of measuring the stenotic severity in this phantom study. Objective: We wanted to evaluate the impact of two reconstruction algorithms (halfscan and multisector) on the image quality and the accuracy of measuring the severity of coronary stenoses by using a pulsating cardiac phantom with different heart rates (HRs). Materials and Methods: Simulated coronary arteries with different stenotic severities (25, 50, 75%) and different luminal diameters (3, 4, 5 mm) were scanned with a fixed pitch of 0.16 and a 0.35 second gantry rotation time on a 64-slice multidetector CT. Both reconstruction algorithms (halfscan and multisector) were applied to HRs of 40-120 beats per minute (bpm) at 10 bpm intervals. Three experienced radiologists visually assessed the image quality and they manually measured the stenotic severity. Results: Fewer measurement errors occurred with multisector reconstruction (p = 0.05), a slower HR (p < 0.001) and a larger luminal diameter (p = 0.014); measurement errors were not related with the observers or the stenotic severity. There was no significant difference in measurements as for the reconstruction algorithms below an HR of 70 bpm. More nonassessable segments were visualized with halfscan reconstruction (p = 0.004) and higher HRs (p < 0.001). Halfscan reconstruction had better quality scores when the HR was below 60 bpm, while multisector reconstruction had better quality scores when the HR was above 90 bpm. For the HRs between 60 and 90 bpm, both reconstruction modes had similar quality scores. With excluding the nonassessable segments, both reconstruction algorithms achieved a similar mean measured stenotic severity and similar standard deviations. Conclusion: At a higher HR (above 90 bpm), multisector reconstruction had better temporal resolution, fewer nonassessable segments, better quality scores and better accuracy of measuring the stenotic severity in this phantom study.