• 한국응용곤충학회지
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• 제42권1호
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• pp.29-34
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• 2003

귤응애 성충의 표본추출법을 개발하기 위하여 2개년(2001-2002년)동안 8월부터 11월까지 잎과 열매에 대해 각 조사일에 평균밀도를 조사하였다. 잎과 열매에서 귤응애 성충 밀도의 관계를 시기별로 비교하였으며, Taylor's power law (TPL)와 Iwao's patchiness regression (IPR)을 이용하여 분산지수를 비교하였다. 잎(X)과 열매(Y)에서 귤응애 성충 밀도의 관계는 ln(Y+l)=1.029 ln(X+l)($r^2$=0.80)의 직선적인 관계가 있었으며, 열매가 성숙될수록 잎보다 열매에서 귤응애 밀도가 높아지는 경향이었다. 잎과 열매의 표본조사에서 TPL이 IPR보다 평균-분산 관계를 더 잘 나타내었으며, TPL의 기울기와 절편은 두 표본단위간, 연도간에 차이가 없었다. 정착도 0.25일 때 요방제밀도 2.0, 2.5와 3.0에서의 의사결정을 위한 표본추출조사법을 개발하였으며, 조사에 필요한 최대조사나무수(고정표본크기에서 필요 나무수)는 각각 19, 16과 15주였으며, 이 때의 의사결정임 계값 $T_{critical}$은 각각 554,609와 659였다.,609와 659였다.

• Journal of Korean Society for Atmospheric Environment
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• 제19권E1호
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• pp.11-20
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• 2003

To characterize airborne particulate carbon and its temporal variation in the heavily industrialized metropolitan city, Seoul in South Korea, aerosol sampling was performed from 1986 to 1996. Correlation coefficients of elemental carbon (EC) and organic carbon (OC) with mass concentration of fine particles ($\underline{\leq}$2.1 ${\mu}m$) are 0.73 and 0.51, respectively. EC concentrations of the fine particle mode are 10.1, 5.9, 4.5, and 7.4 ${\mu}g\;m^{-3}$ in winter, spring, summer, and autumn, respectively. On the other hand, OC concentration shows maximum value in winter and followed by autumn, summer, and spring. A seasonal peak in the ratio of OC to EC in fine particles was observed during the summer photochemical season from June to August. Concentrations of EC and OC in Asian dust storm events are generally higher than in non- Asian dust storm events except in 1990. The difference of EC concentrations between Asian dust storm periods and non-Asian dust storm periods are much larger than those of OC concentrations. There are slight increases of EC concentration between 1987 and 1990 and a gradual decrease between 1990 and 1996.

• 한국동물위생학회지
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• 제26권1호
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• pp.81-88
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• 2003

A cross-sectional epidemiological study using a multistage sampling strategy in slaughter cattle in Mymensingh, Bangladesh was conducted during September 2001 to April 2002 to study distributions and risk factors of specific pulmonary lesions and diseases. The pulmonary lesions and diseases were diagnosed on the basis of macroscopic and microscopic pathological and parasitological findings. The frequency distribution of pulmonary lesions and diseases in slaughter cattle was found to vary among categories of the study variables. The risk factors identified on statistical basis were male cattle and ${\leq}3$ years old cattle and summer in congestion, slightly thin physical condition and summer season in pulmonary emphysema, slightly thin physical condition in parasitic bronchitis as well as female cattle, autumn and rainy seasons in pulmonary hydatidosis. The population impact and etiologic significance of summer season on pulmonary congestion and emphysema was more important than that of adult male cattle. The population impact and etiologic significance of autumn season on pulmonary hydatidosis was more important than that of female cattle during rainy season. Population impact of slightly thin cattle on parasitic bronchitis was poor.

• 한국지역사회생활과학회지
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• 제23권4호
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• pp.411-418
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• 2012

Phthalates and di-2-ethylhexyladipate are both widely used as industrial chemicals and exposure high levels over long periods of time can cause toxicity, estrogenic responses and endocrine disruption properties in both humans and animals. So far, their global monitoring in environmental matrices has been performed continuously. A developed method, including modified SPEED'98 (Japan Environment Agency) and USEPA was established for simple and rapid determination of phthalates and di-2-ethylhexyladipate in various matrices. This method was applied to explore the distribution levels in domestic environmental media such as water, soil and sediment. Eight phthalates (DEP(di-ethyl), DEHP(di-[2-ethyl-hexyl]), DprP (di-propyl), DBP(di-n-butyl), DPP(di-n-pentyl), DHP(di-n-hexyl), DCHP(di-cyclohexyl), BBP(butyl benzyl) and Adipate (di-2-ethylhexyl adipate) were investigated by seasonal sampling(spring, autumn) at 24 domestic sites. Phthalates and adipate were not detected in water samples and DEP, DBP, and DEHP were mainly detected in soil and sediment samples. The concentrations of DEP and DBP excluding DEHP in spring were higher in soil than those of sediment. Total concentrations of phthalates were significantly decreased in autumn for both soil and sediment.

• Ocean and Polar Research
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• 제41권4호
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• pp.251-263
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• 2019

We investigated the mesozooplankton community structure during autumn in the southern Yellow Sea. Mesozooplankton density generally ranged from 352 to 2,954 ind. m^-3 and varied according to different sampling stations. The copepod Paracalanus parvus s.l. and its copepodites dominated in the communities, corresponding to 57.3% in density of the total. Surface and water-column averaged salinity were positively correlated with density of total mesozooplankton, copepods and a few dominant species, and the tunicate Thalia rhomboides was negatively related to chlorophyll-a concentration. The mesozooplankton community of the study area was divided into three groups according to the cluster analysis using species composition and density: one in the northern coastal region, another in the northern offshore region, and the other in the south. The most significant indicator species for each of the groups were Labidocera euchaeta in the northern coastal region, T. rhomboides in the northern offshore region, and Themisto sp. juveniles in the south. This study provides recent data on the characteristics of the mesozooplankton community in the southern Yellow Sea, which may be valuable for gaining a better understanding of changes in the pelagic ecosystem of the Yellow Sea.

• 한국기후변화학회지
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• 제9권4호
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• pp.377-384
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• 2018

The chamber method is widely used for measuring methane emission from paddy rice fields. The closed static chamber has advantages of easy installation and removal in the field and low manufacturing cost. However, the manual chamber method requires a lot of labor and has a limited sampling time and frequency. To overcome the disadvantages of the manual chamber, the auto-chamber system is used for measuring methane emission. We compared the differences in methane flux between the auto-chamber and manual chamber. To investigate methane emissions by the two methods, a chamber was installed for each of the following treatments : control without rice straw (NA), spring plowing after autumn rice straw application (SPRA) and autumn plowing after autumn rice straw application (APRA). The total methane emission was lowest in the control and highest in APRA with both methods. There was no significant difference in total methane emission between the methods, but dynamic fluctuation in methane with temperature change was accurately measured in the auto-chamber. Measuring methane emission with an auto-chamber system is expected to reduce uncertainty and increase accuracy, accompanied by labor reduction.

• 한국균학회지
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• 제46권2호
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• pp.122-133
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• 2018

순천 선암사는 산림과 계곡으로 둘러싸여 가파른 지형에 위치하고 있으며 평지보다 온 습도는 높고 바람의 세기가 약하여 생물 피해가 우려되는 곳이다. 이에 계절마다 진균상 조사를 통해 실내 외 공기질에 분포하는 진균의 농도와 다양성을 조사하였다. 외부 공기질에 분포하는 진균의 농도는 봄($276CFU/m^3$)에 가장 높았고, 가을($196CFU/m^3$), 여름($128CFU/m^3$), 겨울($24CFU/m^3$) 순으로 감소하였다. 가장 하단에 위치한 지장전은 여름철에 $337.4CFU/m^3$, 가장 상단에 위치한 원통전은 가을철에는 $333.4CFU/m^3$의 가장 높은 농도를 나타냈다. 실내 외 공기질에서 부유균 농도의 차이가 컸던 계절은 여름철이었으며 $128CFU/m^3$인 외부보다 실내 공기질에 최소 0.5배에서 최대 3배 정도의 많은 진균이 부유하고 있었다. 부유 진균이 가장 많이 수집된 계절은 봄철이었지만 다양성은 여름과 가을철 공기질에서 더 높았는데 여름에는 28속 45종, 가을에는 25속 47종의 진균이 확인되었다. 특히, 가을철에는 모든 조사 지점에서 부유 진균의 분포도가 가장 높았는데 그 중에서 자낭균이 86%를 차지하였고 Cladosporium속이 우점하였다. Penicillim속은16종이 검출되어 종다양성이 가장 높았고 야외보다는 여름과 가을, 겨울철의 실내 공기질에 주로 분포하였다.

• 환경영향평가
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• 제14권5호
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• pp.263-273
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• 2005

In this study, the major emission procedures and emission characteristics were identified at the site of sewage treatment plant which is one of the major sources of ammonia. At the same time the emission factors and emission rates were estimated. In order to calculate the emission flux, we used a Dynamic Flux Chamber(DFC), which is found to be a proper sampling devise for area sources such as sewage treatment plant. It was found that the most stable sampling condition was when the stirrer's speed of DFC was 120RPM, and it would be the best time to take a sample 60 minutes later after setting the chamber. The relatively higher flux was shown in Autumn compared to summer and winter. Annual ammonia emission rates procedures were calculated as $906.32{\mu}g/activity-ton$, $1,114.72{\mu}g/activity-ton$ and $437.53{\mu}g/activity-ton$ each at the primary settling basin, aeration basin and the final settling basin, respectively. The ammonia emission rate the highest at in the aeration basin according to this test. This results was due to that the surface of aeration basin or the final settling basin is relatively wider than the primary settling basin.

• 미생물학회지
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• 제22권3호
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• pp.157-165
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• 1984

Seasonal and spatial variations in propagule numbers of Trichoderma species were investigated every other month for one year in deciduous and coniferous forest soils and evaluated the relationships of Trichoderma spp. populations to soil environmental factors. The total population of Trichoderma spp. increased until summer and then declined until winter. The yearly mean frequency of Trichoderma spp. exceeded 1.4% of total fungal propagules in two sites. Decreases of absolute an relative propagule numbers of Trichoderma spp. with increasing soil depth were found and variation in Trichoderma spp. propagules caused by differences in soil depth ($0{\sim}50cm$) was greater than that caused by differences in sampling time. The most common species occurring in two sites was T. viride, followed by T. polysporum, T. koningii, and T. hamatum. Individual species of Trichoderma showed diferent abundance trend in accordance with sampling time. T. viride was dorminant from spring to autumn, while T. polysporum dominated over the other speicies in winter. Variations in propagule number of Trichoderma sppp. were principally mediated by the actions of biotic environmental factors rather than by the direct effects of abiotic factors. In multiple-regression analyses, 48% of the total vaiation in Trichoderma spp. propagules in deciduous site could be accounted for by total fungal propagules and soil CMCase actvity. In coniferous site, 65% of total variation could be accounted for by total fungal and bacterial propagules, moisture content and organic carbon content.

• 한국주거학회:학술대회논문집
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• 한국주거학회 2006년도 추계학술발표대회 논문집
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• pp.322-327
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• 2006

In our previous research, office workers are relatively frequent in self-reported symptoms suggestive of MCS/IEI compare to construction worker who highly exposed to VOCs compounds. However in that research, the subjects were too small to say it clearly. Based on that research results, self reported symptom surveys to 110 office workers and personal exposure concentration measurement were conducted to 13 of people. VOCs exposure levels were measured within office, house and other places during a week by Passive Sampling Method. In this study, it was found that the number of office workers who met the operational criteria of MCS/IEI was 23.6% similar to 24.5% of previous result, and average of TVOC concentration was appeared high state by order of office, house, and personal exposure.