케미컬오일을 이용한 ERF 연마 특성

윤종호,이재종,이응숙,이동주,김영호 한국공작기계학회 2004 한국공작기계학회 춘계학술대회논문집 Vol.2004 No.-

Electro-rheological fluid is recently used for the micro polishing of 3-dimensional micro-aspherical lens. It's also used for polishing small area defects on the wide flat wafer. Since ER fluid shows a behavior of viscosity changing under certain electric fields, micro polishing efficiency may be enhanced for certain cases. In this paper, a perfluorinated carbonyl fluoride oil based ER fluids was used to improve surface polishing rate and submicron-scale accuracy. As the polishing electrodes, micro size cylindrical tools had been used for maximizing the electric field. An experimental device, which was applied for micro polishing a number of wafers of 4 inches in size and other workpieces, was made on a precision polishing system. It consisted of a steel electrode, a wafer fixture, 10mA current and DC 5kV power supply unit, and a controller unit. From the Experiments, the ER fluid is applicable for micro polishing of small parts.

플라보노이드의 세포 신호전달 조절

이응룡,강근호,강용진,김우열,최혜연,김봉우,정효순,조쌍구 충남대학교 형질전환복제돼지연구센터 2007 논문집 Vol. No.10

Many studies revealed the neuroprotective, cardioprotective, and chemopreventive actions of dietary flavonoids. The plausible mechanistic interpretation of the various effects of flavonoids was concentrated on the anti-oxidant or free radical-scavenging properties of these phytochernicals, both in model systems and under in vivo conditions. While there has been a major focus on the anti-oxidant properties. there is an emerging view that flavonoids and their in vivo metabolites. do not act as conventional hydrogen-donating anti-oxidants. but they may exert regulatory functions in cells through actions at protein kinase or lipid kinase signaling pathways. Flavonoids and more recently their metabolites. have been reported to act at phosphoinositide 3-kinase(PI 3-kinase). Akt/protein kinase B(Akt/PKB), protein kinase C (PKC), mitogen activated protein kinase(MAP kinase), and various tyrosine kinases signaling cascades. Inhibitory or stimulatory actions at these pathways are likely to affect cellular function profoundly by altering the phosphorylation state of target molecules and by modulating gene expression. A clear understanding of the mechanisms of action of flavonoids, either as anti-oxidants or modulators of cellular signaling pathways, and the influence of their metabolism on these properties are key to the evaluation of these potent biomolecules as anti-cancer agents, cardio-protectants, and inhibitors of neurodegeneration.

제강전로슬래그를 이용한 하수슬러지 고화체의 미세구조 분석

李基錫,趙珍奎,李昇玟,金應鎬 弘益大學校 科學技術硏究所 1999 科學技術硏究論文集 Vol.10 No.1

The solidifying effect of solidified digested sewage sludge by converter slag was investigated through microscopic analyses including XRD, SEM and EDS. The XRD analysis of the solidified sludge showed that the main solidification products was CSH; in addition, Ca(OH)₂CAH and Ettringite were observed. The microstructure analysis by SEM showed that as the solidification proceeds, needlelike crystals and honeycomb appeared. The analysis of these crystals by EDS confirmed that the main components were Ca, Si etc. This also confirmed the general notion that the cement hydrate products had a solidifying effect.

신장세포암에서 WT1과 IGF2 유전자의 발현

이정호,김응석,김용섭,장성익,윤환중 동국대학교 의학연구소 2000 東國醫學 Vol.7 No.-

IGF2 유전자는 제 11번 염색체 단완 (11p15.5)에 위치해 있으며 아버지로부터 유전된 대립형질만 기능을 하는 genomic imprinting되는 유전자이다. 이 유전자는 정상세포에서는 세포증식을 촉진시키는 작용을 하고 몇가지 암에서는 LOI에 기인한 과발현이 있는 것으로 알려져 있다. 한편 WT1 유전자는 제 11번 염색체 단완 (11p13)에 위치해 있으며 어머니로부터 유전된 대립형질만 기능을 하는 즉 IGF2 유전자와는 정반대의 genomic imprinting 되는 유전자이다. 이 유전자는 비뇨생식기관의 발생에 매우 중요한 유전자이며 암화과정에서는 암억제 유전자로서 기능한다. 소아신장에서 발생되는 Wilms 종양에서는 IGF2 유전자와 WT1 유전자의 고장이 주원인으로 생각하고 있다. 이에 근거하여 성인에서 발생되는 신장세포암에서도 Wilms 종양에서의 결과와 같을 것인지의 여부를 알기 위하여 12명의 신장세포암 환자 ( 남자 6명, 여자 6명)로부터 얻은 조직을 이용하여 이들 유전자의 발현정도를 조사하였다. 환자의 연령은 남자에서는 43세에서 56세까지였고 여자에서는 23세에서 61세까지였다. 신장세포암에서 IGF2 유전자와 WT1 유전자의 발현정도는 다같이 성별이나 연령과는 무관하였다. IGF2 유전자는 50%에서 발현되었으며, 그 발현정도는 저발현에서부터 중등도 그리고 과발현까지 다양했으며 주로 신세뇨관 부위에 있는 암세포에서 발현되었다. WT1은 56%에서 발현되었으며 과발현과 중등도 발현이 대부분이었다. IGF2 유전저의 발현과 WT1 유전자의 발현은 각 예에서 상이하게 나타나서 두 유전자간의 작용은 일치하지 않았다. IGF2 gene which was located on chromosome 11p15.5 is expressed by the paternal allele. It stimulates the cell proliferation in normal cells, however, it is over expressed in some cancers due to LOI (loss of genomic imprinting). In contrast, WT1 gene which was located on chromosome 11p13 shows maternal specific monoallelic expression. It is a very much important gene in developing urogenital system, besides, it acts as tumor suppressor gene in some cancers. IGF2 and WT1 genes are the main causative genes in Wilms tumor which is developed in pediatric kidney. To understand the status of IGF2 and WT1 expressions in renal cell carcinoma which is developed in adult life, tissues from 12 cases patients (male 6 cases ; female 6 cases) were detected by immunohistochemistry with antibodies from IGF2 and WT1 genes. To distinguish the different ages between Wilms tumor and renal cell carcinoma, the patients age in renal cell carcinoma was ranged in 43-56 years old in man and 23-61 years old in female. No direct correlation was, in general, between gene expression of IGF2 and WT1 and age or sex of patients in renal cell carcinoma. Expression of IGF2 gene revealed six of twelve (560%) and expression of WT1 gene showed seven of twelve (56%) in renal cell carcinoma, respectively. The status of IGF2 gene expression was varied from low to high expression. In contrast, the status of WT1 gene expression was higher than in IGF2 gene expression. However, there was no apparent correlation between expressions in each cases. In conclusion, IGF2 and WT1 genes are very important in carcinogenesis of renal cell carcinoma, however interaction between two genes was obscure.

直接波 逆信號에 의한 音響 Feed Back 制倨에 관한 硏究

李應頀 서울교육대학교 과학교육연구소 1995 科學과 數學敎育 論文集 Vol.21 No.-

Acoustic feed back system is the oscillating phenomenon occured in the loop which is formed by loud speaker, microphones and amplifier in sound reinforcement system. If we turn up the gain of amplifier to increase the sound volume, sound reinforcement is impossible because of the oscillation due to this loop. A few methods such as echo cancelling system and linear array of non-directive microphones for howling prevention have been studied by others. It is the purpose of this paper to investigate the possibility of acoustic feed back by negative signal of direct wave. The time delay circuit was used to minimize the difference of the out-put voltages by adjusting the distance between two micro-phones whose frequency characteristics of the out-put voltage are similar to each other from loud speaker. The signal of the first microphone and the opposite signal of the second micro-phone are added in the adding circuit. The results of this investigation are as follows; a pair of microphones, that the frequency characteristic difference of the out-put voltage is minimum under the constant acoustic pressure, could be selected by adding two signals in the adding circuit. It could be possible to minimize the difference of transfer characteristic by adjusting the distances between two microphones, by use of time delay circuit. In the room with absorption mats, the howling level gain above 10 dB could be achieved by use of the acoustic feed back control part(time delay circuit, adding circuit and comb filter), but in the ordinary lecture room, howling level gain was low because of the interference of reflective waves from various objects and noise as well.

乾燥 「개불」의 extract에 대하여

李應昊 釜山水産大學校 1968 釜山水産大學 硏究報告 Vol.8 No.1

乾燥 "개불"의 유리 아미노酸 定量 및 表面에 생긴 白粉物質의 成分을 同定한 結果, 유리 아미노酸중에 특히 많이 함유되어 있는 것은 glycine, alanine이고 이 두 아미노酸이 全 유리 아미노酸의 약 80%를 차지하였다. 또한 白粉物質에서 glycine과 alanine을 檢出하였다. 이런 것으로 미루어 보아 "개불"의 단맛은 glycine과 alanine에 의한 것이라고 볼 수 있다. 끝으로 本實驗은 東京水産大學 食品保藏學硏究室에서 하였으며 實驗을 지도하여 주신 野中順三九博士, 그리고 實驗을 協助하여 주신 須山三千三博士 및 小泉千秋氏에게 깊은 謝意를 表한다. "Gae-bul", raw or sun-dried, has been esteemed as one of the most tasty sea foods in Korea. The free amino acids in sun-dried "gae-bul" were analysed by an auto-analyser (HITACHI Co. LTD., KLA-2) using Amberlite CG-120 column and the major components contributing to the sweet taste of the product were shortly discussed. A characteristic pattern of the amino acid composition was that glycine was about 60% of total amino acid content and alanine was about 20%. In addition, more than 74% of the total nitrogen in the extracts was found to be free amino acid nitrogen. More over, it was found that the white crystal-like solids on the surface of sun-dried "gae-bul" mainly consisted of glycine and alanine. These facts convinced that the sweet taste of sun-dried "gae-bul" attributed to such amino acids as glycine and alanine, known as sweet compounds.

Microphone比較測定의 精度에 關한 檢討

李應頀 서울교육대학교 과학교육연구소 1985 科學과 數學敎育 論文集 Vol.11 No.-

自然科 探究 學習에 관한 實험 模索 : 電氣 回路 單元을 중심으로 with the unit about electric circuits

李應護,具德吉 서울교육대학교 과학교육연구소 1995 科學과 數學敎育 論文集 Vol.21 No.-

Pion-Nucleon Scattering in Phase Shift Analysis below 400 MeV/c

李應頀,金成度 서울교육대학교 과학교육연구소 1995 科學과 數學敎育 論文集 Vol.21 No.-

본 연구는 400 MeV/c 이하의 에너지 영역에서 위상이동분석(S-, P-, D-파)을 소개하고 그 물리적 의미 및 위상이동에 의한 파이온-핵자 산란단면적을 연구하였다. 이들 에너지 영역에서 π^+p 반응은 이용가능한 실험치와 좋은 일치를 보여 주고 있으나, π^-p 반응은 │p│?? 150 MeV/c보다 낮은 에너지에서 다소 차이를 보여 주었다. 본 연구의 결과로부터 π^-p 반응에서 나타나는 I=1/2에 대한 위상이동은 낮은 에너지 영역에서 더욱 정확한 분석을 요구한다. We have introduced pion-nucleon phase shifts(S-, P-, and D-wave), to study its physical properies, and to provide the cross sections of pion-nucleon scattering calculated using fitted phase shifts for energies below 400 MeV/c. In this energy region, we have found that the agreement is quite respectable for π^+p at all energies, but less good for π^-p below |q| ?? 150 MeV/c.

油腐加工 중의 기름의 性狀變化 및 油腐貯藏 중의 品質變化

李應昊,鄭淑鉉,金根淑,金喜衍 釜山水産大學校 1981 釜山水産大學 硏究報告 Vol.21 No.2

油腐 튀김過程중 튀김用 기름의 性狀變化를 作業時間 經過에 따라 工場規模로 檢討하고 油腐를 4가지 貯藏方法으로 貯藏하여 貯藏期間에 따른 品質 變化를 實驗한 結果는 다음과 같다. 1. 튀김用 기름의 性狀變化에 있어서 산값과 色調는 低溫튀김솥(110±10℃) 및 高溫튀김솥(200±10℃)의 기름의 경우 모든 作業時間에 따라 增加하였으며 특히 低溫튀김솥의 기름의 變化가 더 컸다. 2. 과산화물값과 TBA값은 低溫튀김솥의 기름의 경우 增加하다가 減少하였으며 高溫튀김솥의 경우는 變化가 거의 없었다. 3. 油腐에서 抽出한 기름의 性狀은 高溫튀김솥의 기름의 영향을 크게 받았다. 4. 貯藏方法에 따른 油腐의 品質變化에 있어서 常溫(26±2℃) 貯藏의 경우 包裝하지 않은 것이 包裝한 것보다 貯藏性이 높았으며 脂肪의 酸敗面에서 볼 때 包裝하지 않은 것은 60日程度 貯藏이 가능하였다. 5. 4±2℃에서 貯藏할 경우에는 貯藏 期間에 따른 脂肪의 酸敗는 적었지만 長期貯藏은 困難하였고 -20℃에서 貯藏할 경우에는 貯藏期間에 따른 品質의 變化가 거의 없었으며 貯藏性이 매우 좋았다.