• 한국항해항만학회:학술대회논문집
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• 한국항해항만학회 2004년도 추계학술대회
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• pp.159-166
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• 2004

바다와 육지의 경계에 있는 해변은 매우 동적인 해역으로 여기에 해수의 운동이 퇴적물, 육지의 바위 또는 인공구조물과 상호 작용한다. 심한 태풍이나 폭풍이 야기한 파랑의 영향으로부터 해변의 침식을 막거나 지연시키기 위해 영구적인 구조물을 설치하지만 해양경관을 해침은 물론 이의 파급효과로 또 다른 침식현상이 일어나기도 한다. 파가 부숴지는 쇄파대와 쇄파선 밖의 외해에서 표사의 이동 및 침식을 가속시키는 관련 에너지를 고려할 때에는 파고 및 파의 주기를 고려하여야 한다. 본 연구에서는 이러한 부차적인 영향을 나타내지 않으면서 파력을 줄일 수 있는 해저 구조물로 인공 Bio-reef를 도입하고 이를 통한 해양생태계의 복원의 예와 아울러 수치모델을 도입하여 가장 근원이 되는 파랑의 저감효과를 분석하여 적용가능성을 제시하고자 하였다. 해변을 보호하기 위한 새로운 기술은 인공적 및 자연적 켈프 또는 해양식물을 식생시킨 해저리프에 의한다. 연안리프의 형상을 공학적으로 접근하여 각각의 파랑저감력을 최적화할 수 있다 높고 넓은 긴 인공 리프는 파랑에너지를 막을 수 있는 좋은 장벽이 되나 공사재료의 양, 항해위험, 건설방법 및 다른 인자에서 리프의 전체 설계에 대해 공학적인 고려가 필요하다.

• 대한수의학회지
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• 제35권2호
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• pp.217-228
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• 1995

The study was designed to investigate the effects of progesterone on the reproductive system. This investigation was performed by immunohistochemical methods using anti-bromodeoxyuridine-antibody following bromodeoxyuridine(Brdur) injection for labeling proliferating cells in the uterus and ovary of rats. Sixteen female rats(Wistar), weighing initially 300g, were randomly allotted into ovariectomized and unovariectomized large groups. These two large groups were subdivided into three subgroups of control, 3-day and 6-day groups, respectively. 3-days and 6-days group were injected with 1mg of progesterone/rat/day for 3 or 6 days, respectively. In gross findings, the uterus of ovariectomized groups markedly atrophied, and were not hypertrophied by progesterone injection for 3 days or 6 days and the uterus of unovariectomized groups also were not hypertrophied. Labeling index(LI, %) was measured by counting the number of Brdur-positive cells from 300 to 3,000 cells per layer in the uterus tissue. The average LI of the uterus in unovariectomized groups was higher than that of ovariectomized groups. The subgroups with higher LI in unovariectomized groups were ordered as 6-day group, 3-day group. So progesterone considerably effected to the proliferating of the cells in the uterus of unovariectomized groups. The layers with higher LI in the uterus wall were ordered as the functional zone of endometrium, epithelial layer of endometrium, basal zone of endometrium, myometrium and perimetrium. The cell types with higher LI in the uterus of unovariectomized groups were ordered as the surface epithelial cells, stromal cells, glandular epithelial cells and muscle cells. Growing follicles with proliferating cells from secondary and tertiary follicles in the ovary of unovariectomized groups appeared to be 37.66% in control group, 39.23% in 3-day groups, 39.47% in 6-day groups. Mature follicles in the ovary were more number in control group than those in 3-day groups but not appeared in 6-day groups. So progesterone not nearly effects to the number of the growing follicles but appeared to be related to suppression of the development and protrusion of the mid-tertiary and mature follicles on the ovary surface. The cell types with higher LI in the ovary of unovariectomized groups were respectively ordered as granulosa cells, theca interns cells in secondary follicles; theca interna cells, granulosa cells, theca externa cells in tertiary follicles; fibroblasts, theca in terns cells in atretic follicles; fibroblasts, luteal cells in corpus luteum.

• 대한화학회지
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• 제19권5호
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• pp.331-338
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• 1975

크롬산염, 중크롬산염, 요오드산염 및 과요드산염의 중성자포획에 수반하는 크롬-51 및 요오드-128 반조 화학종의 분배를 거름종이 전기영동법으로 검토하였다. 유효반조에너지 및 내부전환의 관점에서 생각하면 중성자 포획원자가 초기분자중에 잔유하고 반조원자에너지가 결정의 적은 범위를 가열하며 소멸된다고 하기 어렵다. 그러나 거름종이 전기영동결과 더 많은 크롬-51 및 요오드-128 반조원자가 어미분자와 결합되어 있음을 알 수 있었다. 잔류율의 관찰결과 반응 이론을 Disorder Model로 설명하였다. 양이온 반경이 클수록 2차 cage를 돌파하는 반조원자의 확율이 높다. 암모늄염중 암모늄이온은 disorder zone에서 환원작용을 하며 잔류율이 낮어졌다. 결정구조에서 자유공간이 크면 잔류율이 낮어졌다.

• 대한가정학회지
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• 제43권2호
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• pp.19-31
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• 2005

The purpose of this study was to evaluate the microbiological quality and assure the hygienic safety of the Bibimbap production in elementary school foodservice in accordance with the HACCP(Hazzard Analysis Critical Control Point) program. The time-temperature relationship and the microbiological quality(total plate count and coliform bacteria count) were assessed to find the critical control point(CCP) during each of the production phase. In the pre-preparation phase, the risk factors of the raw ingredients exceeded the standard level suggested by Solberg et al. Mungbean starch jelly, egg and Kochujang were satisfactory in that no coliform groups were observed over the standard TPC level. In particular, there was a high the risk of beef from the early stages in terms of the coliform level. In the pre-preparation phase, green pumpkin had more coliform groups than the standard level even after washed, which calls for special attention to washing, sterilization, secondary infection of the handler, and the required time for pre-preparation of raw vegetables. In the cooking phase, the temperature of the soybean sprout and mungbean starch jelly decreased to 42$^{\circ}C$ and 26$^{\circ}C$, respectively, which was within the risk zone. In particular, mungbean starch jelly had a great risk factor even after boiling in hot water. During the storage stage before serving, a lot of ingredients were exposed to poor management of temperature and time and thus exceeded the standard level in the total plate counts. In particular, the microbiological count of beef was five times the standard level. Green pumpkins and soybean sprouts were left at 15-38$^{\circ}C$ that is within the risk zone for a long period of time after they were cooked. It is highly recommended that the time of the storage stage before consumption should be shortened and that proper devices should be used to prevent proliferation of bacteria. The number of TPC of the utensils was satisfactory enough, but the knife used exceeded the standard level and thus was a risk factor of bacteria proliferation.

• Structural Engineering and Mechanics
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• 제53권3호
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• pp.481-495
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• 2015

Many hydropower stations in southwest China are located in regions of brittle rock mass with high geo-stresses. Under these conditions deep fractured zones often occur in the sidewalls of the underground caverns of a power station. The theory and methods of fracture and damage mechanics are therefore adopted to study the phenomena. First a flexibility matrix is developed to describe initial geometric imperfections of a jointed rock mass. This model takes into account the area and orientation of the fractured surfaces of multiple joint sets, as well as spacing and density of joints. Using the assumption of the equivalent strain principle, a damage constitutive model is established based on the brittle fracture criterion. In addition the theory of fracture mechanics is applied to analyze the occurrence of secondary cracks during a cavern excavation. The failure criterion, for rock bridge coalescence and the damage evolution equation, has been derived and a new sub-program integrated into the FLAC-3D software. The model has then been applied to the stability analysis of an underground cavern group of a hydropower station in Sichuan province, China. The results of this method are compared with those obtained by using a conventional elasto-plastic model and splitting depth calculated by the splitting failure criterion proposed in a previous study. The results are also compared with the depth of the relaxation and fracture zone in the surrounding rock measured by field monitoring. The distribution of the splitting zone obtained both by the proposed model and by the field monitoring measurements are consistent to the validity of the theory developed herein.

• 한국광물학회지
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• 제27권4호
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• pp.263-270
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• 2014

본 연구는 국내 방연석 광산의 방연석에 대한 납동위원소비 분석 자료를 응용하여 청해진에서 출토되는 청동기에 사용된 납 원료의 산지를 알아보고자 하였다. 또한 부산물로 산출되는 미량원소의 종류와 함량이 산지추정의 보조지표로 이용할 수 있는지의 가능성도 검토하고자 하였다. 장도 청해진에서 출토된 청동기의 납동위원소비를 기존에 일본에서 사용하던 동북아시아 납동위원소비 분포도에 적용하면, 청해진 출토 청동기는 중국산 납을 사용한 것으로 추정된다. 그러나 이를 한반도 납동위원소비 분포도에 적용하면 대상시료 대부분이 한반도 남부 옥천변성대와 영남육괴 지역의 방연석을 사용한 것으로 추정되었다. 또한 미량원소 중에서 은(Ag)이나 안티몬(Sb)의 함량은 동일 지역(zone)의 납동위원소비가 비슷한 서로 다른 광상을 분리하는데 유용한 보조지표로 활용될 수 있을 것으로 판단된다.

• Journal of the Korean Wood Science and Technology
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• 제23권1호
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• pp.42-48
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• 1995

The purpose of this study is to evaluate the efficacy of metabolites produced form Streptomyces rimosus in controlling the growth of sapwood - inhabiting fungi. In order to carry out this task, the following specific fungi were tested : sapstain fungi - Ceratocystis pilifera, Ceratocystis piceae, and Aureobasidium pullulans ; mold fungi - Trichoderma hazianum, Trichoderma viride, Penicillium cirtrinum, and Aspergillus niger. Based on the tests, the following observations can be drawn. 1. The conidial germination of sapstain and mold fungi was completely inhibited leaving a clear zone around the paper disc treated with metabolites. The best inhibition was observed in A. pullulans plate and the least in T. viride. 2. Concentration of SB medium for the production of metabolites from St, rimosus affected antifungal activity of metabolites against sapwood - inhabiting fungi. Metabolites prepared from 1/3${\times}$SB medium showed the best activity and the least activity was observed in metabolites form 1/4${\times}$medium. 3. in vivo and in vitro test using wood blocks, treatment of pine sapwood blocks with metabolites also inhibited conidial germination and thus prevented discoloration. 4. Treatment with metabolites did not change the macroscopic structure of wood and did not cause the discoloration of the surface of wood by pigments produced form St. rimosus. In conclusion the results of this study indicate that antifungal metabloites of St, rimosus could be used for the biological control of sapstain and mold fungi.

• 한국해안해양공학회지
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• 제19권2호
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• pp.136-145
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• 2007

파랑이 수중 천퇴부를 넘어 쇄파하는 경우 파고는 작게 형성되나 강한 이차적 흐름 (쇄파유도류)이 발생한다. 따라서, 임의의 해양구조물이 쇄파대에 위치할 경우에는 단순히 가시적인 파고에만 근거한 파력산정은 과소설계를 초래할 가능성이 있으며 구조물의 안정설계를 위해서는 쇄파유도류의 유속이 가미된 상태에서의 유체력을 정확히 산정하여 반영할 필요가 있다. 본 연구에서는 Boussinesq 방정식 모델을 이용하여 쇄파대내에서의 파고분포와 쇄파유도류를 계산하는 기법을 수립하였으며 과거에 수행하였던 이어도 해양과학기지의 수리모형실험 (1/120)의 모델영역에 적용하였다. 이 계산결과를 이용하여 모형구조물에 작용하는 유체력을 계산하고 수리모형실험 결과와 비교함으로써 쇄파유도류의 영향을 정량적으로 평가하였다.

• 미생물학회지
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• 제36권2호
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• pp.84-90
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• 2000

Psudomonas sp. RY-1이 생성하는 extracellular depolymerase system을 이용하여 단위체의 결가지에 서로 다른 탄소 길이와 불포와기를 함유하는 medium-chain-length polyhdroxyalkanoates (MCL-PHAs)의 생분해도를 시럼실 조건에서 조사하였다. 생분애도는 평파내지에서의 clear zone 형성, 효소 처리에 의한 고분자 현탁액의 탁도 감소 및 호흡량의 경시적 변화로 측정하였다. Pseudomonas sp. RY-1은 MCL-PHA depolymerase의 생성을 통하여 조사된 모든 종류의 MCl-PHAs를 분해할 수 있었으나, 이 효소의 생성은 쉽게 이용될수 있는 이차기질에 의해 저해받는 것으로 나타났다. MCl-PHAs의 분해율이 단위체의 탄소수가 홀수개로 구성된 고분자에 비하여 보다 높았다. 곁가지에 분포화기를 함유한 MCl-PHAs는 불포화기를 갖지 아니하는 고분자에 비하여 분해가 빠르게 이루어졌으며, 이들의 분해는 고분자의 결정화도와 밀접한 관련이 있는 것으로 나타났다.

• 자원환경지질
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• 제31권2호
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• pp.101-110
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• 1998

The purpose of this study is to elucidate the source of U anormaly formed in stream water of the drainage system around the Shinbo talc mine area based on the hydrochemical properties of water masses including surface water and groundwater. The hydrochemical properties of water masses in the Shinbo talc mine area are divide into three types; Type I : $Ca(Mg)SO_4$ type with high U content as shown in the stream water flowout from the mine, Type II : $Ca(HCO_3)_2$ type with high U content as in deep groundwater, Type III : $Ca(HCO_3)_2$, type with low U content as in the other stream water and shallow groundwater. It is necessary to emphasize that in deducing the uranium source, a distinct discrimination between type I and type II is showed in their hydrothermal properties in spite of commonly having a high uranium content, which in turn means the occurrence of a different water-rock interaction processes between both type. All evidences suggest that type II groundwater have acted as a primary media in the transport of uranium and that, as the groundwater flows through the talc mineralization zone, water composition of type II was transformed into that of type I water as the results of a secondary water rock interaction process, caused by imposition of new mineralogically controlled thermodynamic constraints. Consequently, in the viewpoint of hydrochemical exploration, the investigation of the hydrologic circulation system and the hydrogeologic properties for the aquifer of type II groundwater shall be done first of all and will provide a crucial clue on tracing the uranium mineralization zone occurred in the Shinbo talc mine area.