댐의 龜裂發生 構造와 應力轉移에 關한 硏究

이영섭,임희대 忠南大學校 産業技術硏究所 1999 산업기술연구논문집 Vol.14 No.1

Generally the cracking in dams is one of the major problems which dam engineers encounter. Concenteated leaks which can result in internal erosion and piping phenomenon have frequently developed through embandment cracks located directly adjacent to rock abutments at the points of abrupt change in slope, and particularly adjacent to horizontal steps used for haul roads,grouting platforms, and so on . Many studies,such as observation, 1ab test and numerical snalysis have been conducted to reveal the mechanism of internal and expernal cracking. It is considered that unfavourable deformation and stress state are the direct cause of the cracking. Longitudinal and trasverse cracks on the crest is occurred by differential settlements in the core zone and differential deformation between adjacent zones and closely concerned with the fluctuation of water level. While during of after dam construction, the core zone with low stiffness can be in the state of low stress due to load transfer resulted from relative deformation against shell zones or adutments. In order to study cracking and leakage, Juam main dam is adopted to analyze deformation and stress condition. The results of numerical analysis and installation indicate that the tension zone of the right abutments is comparatively manifest and the stress-transfer of the upper part the core is more remarkable than lower part.

Wetting에 의한 필댐 상류측 shell의 거동특성

임희대,백장열,이영섭 충남대학교 산업기술연구소 1999 산업기술연구논문집 Vol.14 No.2

The primary objective of this paper is to see the behavior characteristics of rockfill dam due to wetting. There are many factors which affect the dam failure. One of them is the influence of reservoir filling. Differential movements in dam and foundation develop during reservoir filling, they induced cracking and consequent erosion, and sometimes caused dam failure. One of the major factors contributing to the development of differential movements during reservoir filling is the compression due to wetting which occurs in a wide variety of different types of soils including rockfill. To perform the numerical analysis of dam behavior adequately, the large-scaled triaxial test is needed to consider the effect of wetting on dry and wet rockfill material. But, As the large-scaled triaxial test is high capital cost and not available apparatus for a number of other experiment, it is not applied many case in the country. In this paper, the data of Oroville dam which performed the large-scaled triaxial test is referenced to find out stress-strain curve and hyperbolic parameters on wetting for modeled dam which is not performed the large-scaled triaxial test. So, effect of wetting on modeled dam can be considered for numerical analysis of dam behavior. As a result of numerical analysis, they estimate that horizontal and vertical displacement are increased with the rate of increasing wetting, and shear stress too. Because compression and shear strength is decreased with proceeding wetting. And results of analysis show that load transfer is not affect significantly by the wetting.

다짐함수비 變化에 따른 필댐의 擧動分析

임희대,김태곤,이영섭,고근식 충남대학교 산업기술연구소 1999 산업기술연구논문집 Vol.14 No.2

Compaction water content is a key variable which controls fundamental properties of compacted clay (permeability, deformation and strength). There are three conditions in compaction water content (i.e. dry of optimum, optimum and wet of optimum). Actually, soil mass by compaction is unsaturated condition before seepage therefore, soil suction is the key which is able to explain properties of compacted clay. This paper used results from compacted Pittsburg sandy clay tested under UU test condition from Duncan and Seed in order to determine hyperbolic parameters and simulated behavior of Soyanggang dam as a example. As the results of analysis, dry of optimum presents higher strength and smaller displacement. Wet of optimum is sensitive to water content. Both dry and wet of optimum, any hydraulic fracturing potential does not appear. But dry of optimum is close to hydraulic fracturing.

Trypsin Inhibitor from Streptomyces sp. ( Part 1) Isolation of microorganism and purification of the inhibitor

Yi, Dong-Heui,Seu, Jung-Hwn 한국미생물 · 생명공학회 1982 한국미생물·생명공학회지 Vol.10 No.4

Trypsin에 대한 강한 저해물질을 생성하는 Streptomyces속 균주 AS-707을 토양으로부터 얻어 그 배양액에서 Trypsin inhibitor를 분리정제하여 저해물질의 안정성과 여러가지의 protease에 대한 저해성 여부를 검토한 결과는 다음과 같다. 배양액을 Amberlite IRC-50에 흡착 methanol추출. 2차 Amberlite IRC-50, CM-cellulosecolumn chromatography로 정제하여 active amorphous powder를 얻었는데 이 때의 비율은 26%였다. 분리정제된 물질은 trypsin 이외에 papain, $\alpha$-chymotrypsin, Azotobacter vineiandi protease와 Bacillus subtilis protease 등에 대해서도 저해작용을 나타내었으며, 안정성은 비교적 커서 10$0^{\circ}C$에서 120분간 가열해도 잔존활성이 약90%였으며, pH처리에 대해서는 37$^{\circ}C$에서 처리하면 산에서 Alkali에 걸치는 대단히 넓은 pH범위 (pH 2.0~12.0)에서 안정하였으나 6$0^{\circ}C$에서 처리하면 산에서는 안정하였으나 Alkali에서는 불안정하였다. One strain of Streptomyces sp. (AS-707) isolated from soil was found to produce a biologically active substance that showed a strong inhibitory activity against proteolytic enzymes viz. trypsin, papain, $\alpha$-chymotrypsin, Azotobacter protease, and Bacillus pretense. The substance was separated from culture filtrate by ion exchange column chromatography using Amberlite IRC-50 and CM-cellulose column chromatography. It was found that the recovery yield was 26% as activity basis. The substance was stable in wide pH range from 2.0 to 12.0 at 37$^{\circ}C$, but it was unstable in alkaline pH values at 6$0^{\circ}C$. The activity was thermostable to give 90% activity compared to the intact sample when it was treated at pH5.6 at 10$0^{\circ}C$ for 2 hours.

Venom Inhibitor from Penicillium sp. : (Part 3) Neutralization of snake venom toxicities by the inhibitor in vivo (제 3 보) 蛇毒에 對한 沮害劑의 生體內에서의 中和作用

Yi, Dong Heui 건국대학교 부설 산업기술연구소 1984 논문집 Vol.9 No.-

Penicillium 屬의 한 菌株의 培養液으로 부터 分離한 venom inhibitor, ISV-33,의 animal test 結果는 다음과 같다. A. halys blomhoffi venom의 各 分劃의 necrotic factor와 haemorrhagic factor에 對한 沮害作用能을 가졌으며 Agkistrodon과 Trimeresurus venom의 haemorrhagic factor와 lethalcity에 對한 치료효과가 있었다. 특히 prednisolone을 첨가하면 效果가 더욱 增進되었다. 그러나 誘導體中 methyl ester와 amide는 전혀 效果가 없었으며 sodium, cupric, magnesium salt같은 金屬鹽은 효과가 있었다. 그리고 動物에 對한 毒性은 없었다. A microbial venom inhibitor, ISV-33, was tested to investigate the inhibitory effect on the snake venoms in vivo. It was effective to several fractions of proteinase and haemorrhagic factor of A. halys blomhoffi venom and also effective to the haemorrhagic factors and lethalcity of Agkistrodon and Trimeresurus venom. Moreover, with the addition of prednisolone, it was more effective for the cure of mice envenomated. Its methyl ester and amide had not inhibitory activity, but metal salts viz. sodium, cupric and magneium salt had. And it had no acute toxicity to mouse.

Trypsin Inhibitor from Streptomyces sp. (Part 2) Biological Activities or the Inhibitor

Yi, Dong-Heui,Seu, Jung-Hwn 한국미생물 · 생명공학회 1982 한국미생물·생명공학회지 Vol.10 No.4

Streptomyces속 균이 생산하는 trypsin inhibitor의 trypsin에 대한 반응성을 조사해 본 결과 본 저해물질은 crystalline trypsin (20.000 unit, hog pancreas)에 대하여 1/8량에서 약 50%의 저해률을 나타내었으며 trypsin에 대한 저해양상은 mixed noncompetitive-competitive inhibition type이었으며 enzyme-inhibitor complex를 빨리 형성하는데 반응액중 isoleucine이 공존하면 활성이 증가되였으며 Ag$_{+}$ Hg$_{++}$등의 금속ion은 강하게 본 저해물질의 작용을 억제하였다. 저해률은 사용한 기질의 종류에 따라 차이가 나서 albumin을 사용하였을 때는 casein이나 hemoglobin을 사용하였을 때보다 저해률이 높았다. 그러고 혈액의 응고에 대해서도 저해작용을 나타내었다. Trypsin inhibitor produced by Streptomyces sp. was investigated its reactive characteristics against trypsin. The mode of inhibition against trypsin was mixed type of non-competitive and competitive with casein, and enzyme-inhibitor complex was formed rapidly. The inhibitory activity was increased by the addition of isoleucine and depressed by silver, mercuric or cupric ion. And when egg albumin or hemoglobin was used as substrate for trypsin, the inhibition ratio was changed. The inhibitor inhibited coagulation of blood of bovine.

Optimal Grade Transition with Partially Structured Model in a Slurry-Phased HDPE Reactor by Modified Hierarchical Dynamic Optimization

Heui-Seok Yi,Chonghun Han,Sang-Seop Na,Jinsuk Lee 제어로봇시스템학회 2001 제어로봇시스템학회 국제학술대회 논문집 Vol.2001 No.10

Identification of a Alkaline Protease Producing Streptomyces and Production Conditions for the Enzyme

Yi,Dong Heui 건국대학교 부설 산업기술연구소 1985 논문집 Vol.10 No.-

토양에서 分離한 Streptomyces屬 菌株 YS-331同定 및 alkaline protease 生産條件을 검토한 결과는 다음과 같다. 菌의 형태, 배양, 생리적특성으로부터 同定한 결과 Streptomyces fulvoviridis였다. 酵素生産을 위한 탄소원으로서는 sucrose가, 질소원으로서는 peptone이 가장 우수하였다. 생산최적 initial pH와 온도는 각각 8.0과 25℃였으며, sucrose 1.5%, peptone 0.15%, K₂HPO₄ 0.1%, MgSO₄ㆍ7H₂O 0.05%, NaCI 0.05% 組成의 培地에서 4~5일간 배양하였을 때 효소생성량이 최대에 達하였다. A microorganism capable of producing alkaline protease was isolated form soil and identified as Streptomyces fulvoviridis on the morphological, cultural and physiological characteristics. For the enzyme production, sucrose and peptone was favorable as carbon nitrogen source, respectively. The enzyme production was slightly increased by magnesium salt. but depressed markedly by silver, lead and mercuric salts. Optimal initial pH and temperature for the enzyme formation was pH 8.0 and 25℃, respectively. The production of the enzyme reached at maximum after 5 days cultivation in the medium containing 1.5% sucrose, 0.15% peptone, 0.1% K₂HPO₄, 0.05% MgSO₄ㆍ7H₂O and 0.05% NaCI.

Properties of calcium alginate-entrapped yeast whole-cell invertase

Yi,Dong Heui 건국대학교 부설 산업기술연구소 1986 논문집 Vol.11 No.-

Calcium-alginate에 포괄법으로 고정화한 yeast whole-cell invertase의 고정화 및 작용상을 조사한 결과는 다음과 같다. 고정화는 fiber 보다 bead 형태로 하는 것이 효과적이었으며, 고정화효소의 작용 및 안정 pH 범위는 native invertase 보다 alkali 쪽으로 이동하였고 열에 대한 안정성은 더욱 커져서 60℃에서 2시간 처리하여도 활성이 70%이상 잔존하였으며 activation energy는 4.7kcal/mole이었다. 또 40℃에서 20회 반복 사용했을 때의 잔존 활성도는 60% 정도였으며 1.6×18cm 크기의 column을 사용한 packed-bed reactor에서의 maximal productivity는 250mL/hr의 flow rate에서 3.6mM sucrose hydrolyzed/hr이었다. Yeast whole-cell invertase immobilized on calcium-alginate gel by entrapment was used in this study. Among various entrapped material shape, the bead of 1.5mm diameter was most effective for sucrose hydrolysis at 40℃. The entrapped preparations showed high stability to heat treatment and repeated operations. Activation energy of the entrapped invertase was 4.7kcal/mole. And the maximal productivity in packed-bed reactor (1.6×18cm) obtained was 3.6mM sucrose hydrolyzed/hr at the flow rate of 250mL/hr.

Biochemical Properties of a Venom Proteinase Ingibitor from Penicillium sp.

Yi, Dong Heui 건국대학교 부설 산업기술연구소 1983 논문집 Vol.8 No.-

토양에서 分離한 Penicillium sp. L-175의 培養液으로부터 venom proteinase inhibitor(ISV-33)을 정제하여 生化學的 性質을 조사한 결과는 다음과 같다. ISV-33은 venom의 1/4∼1/2量을 사용하여도 거의 完全한 沮害效果를 얻었으며 기질의 種類나 농도에 영향을 받지 않았기 때문에 酵素단백질 자체에 作用함을 알 수 있었다. 또 金屬에 對한 chelating effect가 없는 순수한 inhibitor로 作用하였다. 그리고 ISV-33은 반응계 內에 Zn이나 Cu鹽이 존재하면 活性이 억제되었다. A venom proteinase inhibitor was purified from culture fluid of Penicillium sp. L-175 and it was named ISV-33. It had a powerful inhibition activity against Agkistrodon halys blomhofii, A. blomhofii brevicaudus, A. saxatilis, A caliginosus, Trimeresurus flavoviridis, T, okinavensis venoms, and had very high specificity to the snake venom proteinases. ISV-33 did not had chelating activity but its activity was depressed markedly by the addition of zinc or cupric salt. And the inhibition degree was not affected by the kind and concentration of substrate. The maximum inhibition ratio was obtained when ISV-33 was equivalent to 1/4∼1/2 amount of the enzyme in vitro.