• 한국미생물·생명공학회지
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• 제30권2호
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• pp.151-156
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• 2002

내열성 $\beta$-glycosidase 효소를 생성하는 균주를 분리하기 위해서 일본의 Atagawa 온천지역에서 시료를 채취하였다. 조효소액이 $70^{\circ}C$에서 4시간 동안 $\beta$-glycosidase활성을 유지하는 KNOUC 202를 선발하여 분리, 동정하였다. 선발된 KNOUC 202는 호기성으로 그람음성 간균이며, 포자를 형성하지 않으며, 운동성이 없으며, carotenoid를 생성하고, catalase, oxidase 양성으로 나타났으며, 최적 성장온도는 $70~72^{\circ}C$이고, 최적 pH는 7.0~7.2이었으며, NaCl 3% 농도에서 성장하였다. 세포내 지방산의 주성분은 iso-15:0과 iso-17:0이었다. KNOUC 202의 16S rRNA sequence는 Thermus thermophilus ATCC 27635(HB8)와 유사도가 99.9% 이었다. 따라서 형태학적, 이화학적, 생화학적 특성, 지방산조성 및 16S rRNA sequence 분석결과에 근거하여 KNOUC 202를 Thermus thermophilus로 동정하였다.

• 한국의류학회지
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• 제17권4호
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• pp.518-528
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• 1993

The purposes of this study are to know the environmental conditions of rural houses, thermal sensation and clothing weight of rural residents and to estimate the standard clothing weight according to their indoor living temperature. In this study, the 631 rural residents of both sexes and all generations were selected from 5 rural districts of Kyunggi, Kangwon, Chungnam, Chonnam and Kyungbuk province and the surveys which include clothes, environmental conditions and thermal sensation carried out 4 times-once in each season-from July 1989 to April 1990. The results of this study are· as follows. 1. The ranges of outdoor temperature are $21{\sim}31^{\circ}C$ in summer, $7{\sim}20^{\circ}C$ in spring/autumn, $-15{\sim}5^{\circ}C$ in winter and those of indoor temperature are $24{\sim}31^{\circ}C$ in summer, $15{\sim}23^{\circ}C$ in spring/autumn, $11{\sim}17^{\circ}C$ in winter. The ranges of indoor temperature is within comfortable range in spring, summer and autumn but in winter it is below the range. 2. There is a negative relationship between indoor temperature and clothing weight(r = -0.927) and the simple regression equation is as follows. Y = -61.97X + 2048.44(Y : total clothing weight $g/m^2$, X : indoor temperature $^{\circ}C$). 3. There is no significant difference of clothing weight among the thermal sensation, so clothing insulation can not affect the thermal sensation. 4. Clothing weight of light-clothing-weight group is 70~75% of middle-clothing-weight group and clothing weight of heavy-clothing-weight group is 130% of middle-clothing-weight group. So the standard clothing weight for rural residents in their indoor living is estimated as Fig. 6.

• The Korean Journal of Ecology
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• 제24권4호
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• pp.233-237
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• 2001

Changes of the oribatid mite species composition during the litter decomposition was investigated in the north-facing and south-facing slopes with different lower vegetation (annual herbaceous plants in north and perennial Sasa in south) in the altitude 1,000 m of Mt. Jumbong, a nature reserve area in Korea, from August 1994 to September 1995. Total 58 species of oribatid mites were collected. The values of O1son's negative exponential index (k) were -0.56 in the south-facing slope and -0.49 in the north-facing slope, but there was no significant difference between them. The decomposition rate of litter increased rapidly until Oct. 1994, and decreased thereafter. Intensive settlement of the forest litter by oribatid mites was recorded in the autumn periods and it decreased in the next spring and summer. Species diversity index (H'), and species evenness (J') ranged from 1.74 to 2.69, and from 0.57 to 0.93, respectively, and the values were lowest in spring. In the successive periods of growing season, there followed great changes in the structure of species dominance. Heminothrus minor was one of the most dominant species in autumn in the first year when litter were placed, but was never recovered next seasons. In contrast, Platynothrus yamasakii was also dominant in the first autumn, then decreased very low in numbers in next spring and summer, but regained its number in autumn. On the other hand, an increase of the number during these periods was observed by Epidamaeus sp.2. Ceratopia bipilis and Epidamaeus sp.1 were abundant both in the north-and south-facing slopes. Trichogalumna nipponica was only found in the south-facing slope, and Nanhermannia elegantula was only found in the north-facing slope.

• 한국해양학회지:바다
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• 제13권4호
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• pp.308-319
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• 2008

아산만 해역에서 2005년 2월부터 6월까지 환경 요인과 플랑크톤 군집의 변화를 파악하고 이들 간의 상관관계를 파악해 보았다. 수온은 전형적인 겨울철과 봄철의 수온양상을 보였고, 염분의 변화는 크지 않았다. 식물플랑크톤은 2월에 만의 안쪽에서 첫 번째 peak를 보인 후 5월에 만 전체적으로 두 번째 peak를 보였다. 수온의 증가는 식물플랑크톤 우점종의 천이를 유발하여 2월의 식물플랑크톤 대증식기에는 규조류가 가장 우점하였으며, 5월에는 규조류와 은편모조류가 혼재하며 발생하였고, 6월에는 와편모조류가 우점하였다. 일반적으로 연안해의 식물플랑크톤 대증식은 봄철과 가을철에 발생하는 것으로 알려져 있으나 아산만 해역에서는 이보다 약 한달 정도 빠르게 발생하는 것으로 나타났다. 또한, 식물플랑크톤 대증식시에 산염은 활발히 흡수되어 식물플랑크톤 성장에 이용되었고, 질산염은 제한 영양염으로 작용하였다. 중형동물플랑크톤은 수온과 유의한 양의 상관관계를 보였고, 식물플랑크톤과는 음의 상관관계를 보였다. 중형동물플랑크톤은 식물플랑크톤의 대증식이 발생한 $2{\sim}3$달 이후에 개체수가 증가하였다. 증가한 수온과 먹이로 인해 동물플랑크톤 군집이 성장한 것으로 해석된다.

• Smart Structures and Systems
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• 제31권3호
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• pp.213-227
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• 2023

A passive prismatic-shaped isolation platform (PIP) is proposed to realize enhanced quasi-zero stiffness (QZS) effect. The design concept uses a horizontal spring to produce a tunable negative stiffness and installs oblique springs inside the cells of the prismatic structure to provide a tunable positive stiffness. Therefore, the QZS effect can be achieved by combining the negative stiffness and the positive stiffness. To this aim, firstly, the mathematical modeling and the static analysis are conducted to demonstrate this idea and provide the design basis. Further, with the parametric study and the optimal design of the PIP, the enhanced QZS effect is achieved with widened QZS range and stable property. Moreover, the dynamic analysis is conducted to investigate the vibration isolation performance of the proposed PIP. The analysis results show that the widened QZS property can be achieved with the optimal designed structural parameters, and the proposed PIP has an excellent vibration isolation performance in the ultra-low frequency due to the enlarged QZS range. Compared with the traditional QZS isolator, the PIP shows better performance with a broader isolation frequency range and stable property under the large excitation amplitude.

• 대기
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• 제19권1호
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• pp.67-78
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• 2009

A strong negative correlation has been detected between the North Pacific Oscillation Index (NPI) and the Effective Drought Index (EDI) in May over Korea. In May of positive NPI year, anomalous patterns caused a drought in Korea as follows: the anomalous south-low, north-high low-level pressure patterns in the northeast and southeast of Korea have strengthened the anomalous northerlies to Korea. In addition, these anomalous northerlies have prevented western North Pacific (WNP) high from moving northward. As a result, anomalous descending flows have strengthened in the mid-latitude region in East Asia. In the WNP, the anomalous south-high, north-low sea surface temperature (SST) has been widely distributed, which has strengthened anomalous south-low, north-high low-level pressure patterns. These anomalous characteristics of pressure and SST patterns observed in May of positive NPI years have already been detected in previous winter (December-February) and early spring (March, April). In addition, the anomalous negative sea ice concentration in the North Pacific during two seasons has strengthened the anomalous anticyclonic circulation in the same region and in turn made a contribution to formation of anomalous south-low, north-high pressure patterns in May.

• ALGAE
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• 제18권3호
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• pp.207-215
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• 2003

Dynamics of phytoplankton communities were investigated at five stations in Youngsan River from December 1995 to November 1996. Phytoplankton were identified to the total of 466 taxa, which were composed of 136 genera, 438 species, 27 varieties and 1 forma. The standing crops ranged 1,163-50,765 cells ${\cdot}ml^{-1}$ during the investigation periods. The variation of classes was in order to Chrysophyceae - Bascillariophyceae - Chlorophyceae at St. 1 and was only Bacillariophyceae at the other stations. The dominant species were 12 taxa including Aulacoseira ambigua, A. garnulata, Cyclotella meneghiniana, C. pseudostelligera, Chlorella vulgaris, Dinobryon sertularia, Flagilaria elliptica, Monoraphidium contortum, Micractinium pusillum, Nitzschia palea, Scenedesmus grahneisii and Stephanodiscus hantzschii f. tenuis. The standing crops of dominant species ranged from 10.6% to 94.7%. The genus Dinobryon in Chrysophyceae was dominant species at St. 1 in December 1995, but not recorded in the other months. The dominant species were composed with the planktonic diatoms from winter to spring and were the tychoplanktonic and the benthic species at St. 2-5 from summer to fall. The relationships between total standing crops and water temperature, pH, $NH_4$, $NO_2$, $NO_3$ and $PO_4$ showed low positive or negative coefficients. Stephanodiscus hantzschii f. tenuis had low positive or negative coefficients with water temperature, $NH_4$, $NO_2$, $NO_3$ and $PO_4$. The fluctuations of standing crops in the Youngsan river phytoplankton community were not caused by a single factor but controlled by the complex factors with interaction between phytoplankton community and envirowmental factors.

• 상하수도학회지
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• 제24권4호
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• pp.407-412
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• 2010

The purpose of this study was to investigate removal efficiencies of contaminants in night soil treatment plant using the B3 system. The samples were collected from retaining tank and settlement tank in Yechon night soil plant. We experimented concentrations of BOD, COD, SS, TN and TP. Concentration data were processed using removal efficiencies by season and correlation analysis with pilot running parameters. Removal efficiencies of total organic carbon was over 96%, TN was 98% during summer, 80.9% during winter. In the case of TP, the highest removal efficiencies was 94.1% during fall and the lowest removal efficiencies was 82% during spring. Results of correlation analysis showed two positive correlation groups and one negative group. Positive correlations were among temperature, BOD and TN. The others were pH, BOD, COD, SS, TN and TP. Negative correlation were among MLSS, BOD, COD, SS, TN, TP.

• 한국해양학회지:바다
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• 제11권3호
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• pp.108-116
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• 2006

본 연구에서 Acartia hongi 춘계 개체군 형성의 영향 요인을 파악하기 위해 알 생산, 알 부화시간, 알 포식에 관한 조사가 수행되었다. 알 생산은 동계부터 춘계 사이에 높은 수준을 유지하였다. 알 생산은 수온이 $7^{\circ}C$ 이하일 때 수온 증가에 따라 증가하였으며, 수온 $7\sim21^{\circ}C$ 사이에서는 클로로필 a 농도와 유의한 양의 상관관계를 나타냈다. 알부화 시간$(D_e,\;day)$은 수온$(T,\;^{\circ}C)$에 따라 다음과 같은 회귀식이 얻어졌다. $D_e=18.9(T-0.4)^{-1.0}$ 알 부화 시간은 수온 $5^{\circ}C$ 이하에서 급격히 길어지는 경향을 보였다. 시간차에 따른 A. hongi의 성장 단계별 현존량 변화의 상관관계를 보기 위해 교차상관분석(CCA)을 수행하였다. 개체군 알 생산율에 부화시간을 고려한 알 생산은 개체군 알 생산을 보다 노플리우스 현존량과 유의한 상관관계를 보였다. 이는 부화 시간도 개체군 형성에 영향 요인이 됨을 의미하며, 특히 동계에 높은 일간 알 생산율과 저수온에 대한 부화 지연으로 야기된 높은 알 현존량은 춘계 초기 노플리우스 개체군의 기원이 될 것으로 본다. 춘계 개체군 형성의 부정적인 요인으로 Noctiluca scintillans의 알 포식이 관찰되었다 N. scintillans전체 개체수의 $2.9\sim21.1%$에서 A. hongi 알이 관찰되었으며, 이는 A. hongi 개체군 알 생산율의 $1.2\sim49.5%$에 해당한다. 결론적으로 A. hongi춘계 개체군 형성에 영향 요인으로 동계 세대에 의한 지속적으로 높은 알 생산, 저수온에 따른 부화 지연 그리고 N. scintillans의 알 포식 등이 고려된다.

• 한국자원식물학회지
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• 제33권2호
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• pp.106-115
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• 2020

본 연구는 봄 식물계절지수와 기온지표와의 관계를 알아보기 위해 지난 9년간(2010년-2018년) 대구수목원, 팔공산, 주왕산, 가야산에 공통적으로 생육하는 소나무, 일본잎갈나무, 신갈나무, 진달래, 생강나무, 당단풍나무 6종을 대상으로 발아, 개화, 개엽의 봄 식물계절 시기의 변화 경향과 기온간의 관계를 파악하였다. 기온의 변화는 9년동안2월 보다 3~4월의 월평균 기온이 증가하였으며, 지역별로 수목원과 팔공산의 평균기온이 높았다. 발아, 개화, 개엽은 수종별로 생강나무가 가장 빠르며 소나무가 가장 느렸고, 지역별로 수목원에서 가장 빨리 식물계절시기가 도래하였다. 봄 식물계절시기는 -1.267~-6.151일/9년 정도 앞당겨지고 있는 경향을 보이는데 소나무(-6.151일/9년)가 가장 크며, 진달래(-1.267일/9년)의 변화율이 가장 낮았다. 발아, 개화, 개엽에서 모두 유의한 값을 보이는 수종은 진달래와 소나무로서 이들은 1월~3월 평균기온과 상관관계를 보였다. 봄 식물계절지수(SPI)의 시계열 변화를 확인한 결과 4개 지역의 변화율이 모두 음의 값으로 식물계절 시기가 모두 빨라지고 있었다. 그 중 수목원, 팔공산 및 가야산과 같은 내륙지역일수록 변화율이 컸으며, 다소 거리가 떨어진 주왕산의 경우 변화율이 조금 낮게 나타났다.