• Title/Summary/Keyword: 계절 차이

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Ecological Study on Aquatic Plant Communities in the Stream of Thermal Wastewater (온배수 유입하천에 형성된 수생식물군집의 생태학적 연구)

  • 길봉섭;유현경
    • Korean Journal of Environmental Biology
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    • v.17 no.2
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    • pp.139-146
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    • 1999
  • The seasonal changes of the flora at three samples sites such as Sockchong, Wang-gung and Chukrim hot spring by drained thermal waters were investigated from 1997 to 1998. Monthly occurrence of plant species in February and October showed more abundantly control site than that of heavy and/or light polluted sites. This trend demonstrated similarly in terms of seasonal changes of leaf area and plant growths, both fresh and dry weight, too. Cu, Zn, Ni and Pb content including plants from Sockchong hot spring site were increased from April to September at test area than that of control, while that was decreased in October. But Zn and Pb content holding plants from Wang-gung hot spring site represented higher test site than that of control. In short impacts on aquatic plants communities by thermal wastewater of sampled area have happened in the season of low temperature, and their restorations have done in summer season.

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Long-Period Sea Level Variations around Korea, Japan, and Russia (우리나라 근해의 장기적인 해수면변화)

  • PANG Ig-Chan;OH Im-Sang
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.27 no.6
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    • pp.733-753
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    • 1994
  • Monthly mean sea levels from 103 tidal stations in Korea, Japan, and Russia are analyzed to study long-period sea level variations. Barometric adjustment are done for all the sea level data, using monthly air pressures at sea levels from meteorological stations near tidal stations. Seasonal variation is dominant in most of study area. It is the largest in the coasts along the Tsushima Current, and the smallest in the Russian coasts. The cross-correlations of seasonal variations are very high between the coasts along the Tsushima Current. In these marginal seas, seasonal variations seem to be related with the Tsushima Current. The phase of seasonal variations is generally getting late from south to north, and also from west to east. On the other hand, longer-period variations(longer than seasonal variation) have the largest amplitudes and the earliest phases in the coasts along the Pacific Ocean, which shows that they propagate from the Pacific Ocean. Shorter-period variations (shorter than seasonal variation) have generally lower cross correlations. Their values do not show any dictinct difference between areas, and show a common tendency that they are inversely proportional to distance. It implies that the shorter period waves are generated all over the study areas, and propagate in all the directions with faster dissipations. The trends of sea levels in the study area are generally negative in the coasts along the Pacific Ocean and positive in the other areas during the period of 1965 to 1985. By the trends, the mean volume transport between Cheju and Sasebo can be reduced by about 1 Sv during the period. The seasonal variation of volume transport obtained by sea level difference is about 2 Sv in the Korea Strait. The values are comparable to previous reports.

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Effects of Elevated CO2 Concentration on Leaf Phenology of Quercus acutissima (이산화탄소 농도 증가가 상수리나무 잎의 계절현상에 미치는 영향)

  • Seo, Dong-Jin;Oh, Chang-Young;Han, Sim-Hee;Lee, Jae-Cheon
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.16 no.3
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    • pp.213-218
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    • 2014
  • Effects of elevated $CO_2$ on leaf phenology of Quercus acutissima were examined using open-top chambers, which had ambient and elevated $CO_2$ concentrations (ambient ${\times}1.4$, ambient ${\times}1.8$). To analyze the effect of chamber, non-treatment block was established near outside of the chambers. In 2013, budburst, leaf unfolding, coloring, and shedding were surveyed, and spring phenology was surveyed in 2014. Thermal sum (base temperature $+5^{\circ}C$) of each phenological event occurred was recorded. In addition, bud samples were collected and analyzed for carbohydrate contents in March 2014. Elevated $CO_2$ concentration advanced budburst and leaf unfolding, and delayed shedding in 2013. However, in 2014, the temperature of the spring season was high, and there was no significant effect of elevated $CO_2$ concentration on spring phenology. Carbohydrates content, such as starch, total non-structural carbohydrate and total soluble sugar, were significantly increased in response to elevated $CO_2$ concentration. It has been proposed that elevated $CO_2$ concentration could extend the growing season of temperate species with increased possibility of frost damage due to early bud opening and leaf unfolding. However, our analysis showed that the increased carbohydrate concentration in bud under elevated $CO_2$ would reduce the possibility of early spring frost damage by acting as cryoprotectant.

Calculating Total Radiances of KOMPSAT-2 MSC (다목적실용위성 2호 MSC 총복사량을 계산하며)

  • 김용승;강치호
    • Proceedings of the KSRS Conference
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    • 2001.03a
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    • pp.85-90
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    • 2001
  • 대기복사모델인 MODRAN를 이용해 다목적실용위성 2호 탑재체인 Multispectral Camera (MSC)의 총복사량에 대한 계산을 수행하고 그 결과를 분석해 보았다. 모델계산은 4계절 조건을 모의실험하기 위해 1월 15일, 4월 15일, 7월 15일과 10월 15일에 대해 중위고 동절기 및 하절기, 그리고 US 표준대기를 사용했다. 다목적실용위성 2호 궤도 조건과 각 계절에 대한 대표적인 태양천정각 (solar zenith angle)을 이용하였다. 사정거리는 대류권 에어로솔 소광계수 (tropospheric aerosol extinction)에 해당하는 50 km를 사용하고 지표의 알비도는 맑은 날 지구 연평균 값에 해당하는 0.135가 사용되었다. 위 4개월 평균치로써 연평균 총복사량은 MSC 계약서에 명시된 값들과 상당한 차이를 보였고 심지어 파장에 따른 경향조차도 서로 다름을 알 수 있었다. 가시광선 대역에서 근적외선 대역으로 파장이 증가함에 따라 두 값의 차이가 커짐을 보였다.

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A Study on Construction of Quick Response Distribution System for Fashion Products in China (중국 패션 유통업체의 시장대응형 프로세스 구축)

  • 염인순;이창호;신용산
    • Proceedings of the Korean Operations and Management Science Society Conference
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    • 2003.05a
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    • pp.351-355
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    • 2003
  • 유행에 민감한 의류업계의 생명은 빠른 대응이다. 특히 중국은 인구가 많고, 국토 면적이 넓어서 동북부와 남부 및 서부지역에서 계절의 변화가 뚜렷한 차이를 보이고 온도 차이가 큼으로 하여 같은 시점에서 서로 다른 계절의 의류가 요구되거나 유행되고 있는 것이 특징이 다. 본 연구에서는 중국의 특성에 맞추어 중국현지의 의류유통회사(약칭 S사)의 생산과 판매중심의 시장대응형 프로세스를 구축하여 상품기획에서부터 상품발주, OEM생산, 입하, 배분, 출하, 판매, 실적집계, 판매평가, 보충출하, 보충생산, 히트상품 및 유사품 재발주 등 일련의 과정을 포함하는 정보망을 구축하여 각 과정에서 발생하는 정보를 실시간으로 집계하고 다각도에서 분석하여 더 빠르고 더 정확한 영업의사결정의 지원을 목적으로 하였다.

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Analysis of Seasonal Variation Effect of the Traffic Accidents on Freeway (고속도로 교통사고의 계절성 검증과 요인분석 (중부고속도로 사례를 중심으로))

  • 이용택;김양지;김대현;임강원
    • Journal of Korean Society of Transportation
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    • v.18 no.5
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    • pp.7-16
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    • 2000
  • This paper is focused on verifying time-space repetition of the highway accident and finding the their causes and deterrents. We classify all months into several seasonal groups, develop the model for each seasonal group and analyze the results of these models for Joong-bu highway. The existence of seasonal effect is verified by the analysis or self-organizing map and the accident indices. Agglomerative hierarchical cluster analysis which is used to decide the seasonal groups in accordance with accident patterns, winter group, spring-fall group. and summer group. The accident features of winter group are that the accident rate is high but the severity rate is low. while those of summer group are that the accident rate is low but the severity rate is high. Also, the regression model which is developed to identify the accident Pattern or each seasonal group represents that the season-related factors, such as the amount of rainfall, the amount of snowfall, days of rainfall, days of snowfall etc. are strongly related to the accident pattern of evert seasonal group and among these factors the traffic volume, amount of rainfall. the amount of snowfall and days of freezing importantly affect the local accident Pattern. So, seasonal effect should be considered to the identification of high-risk road section. the development of descriptive and Predictive accident model, the resource allocation model of accident in order to make safety management plan efficient.

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Observed and Simulated Seasonal Salinity in The Tropical Atlantic ocean, and its Relationship with Freshwater (관측과 모델에서 얻어진 열대 대서양에서의 계절별 염분 분포 및 담수 효과)

  • YOO, JUNG-MOON
    • 한국해양학회지
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    • v.27 no.4
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    • pp.290-302
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    • 1992
  • Seasonal variations of salinity in the upper 500 m of the tropical Atlantic Ocean are examined, based on both climatological seasonal salinity observations and numerical simulations with hydrological forcing. The seasonal cycle of sea surface salinity has strong seasonal variations caused by shifts of the freshwater surplus zone (i.e. the intertropical convergence zone) and the river outflow. The climatological seasonal salinity in this analysis concurs with other independent observations described by Default (1981) and Levitus (1982), but provides more consistent patterns with temperature structure. The effect of salinity on density below 100 m depth in the tropical Atlantic is negligible compared to tat of temperature, which in the mixed layer salinity affects density significantly. The systematic difference between observed and simulated salinity is found to be the fact that the simulated salinity is higher in the subtropics than the observed salinity, and possible sources about the difference are also discussed.

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The Demersal Fishes of Asan Bay -III. Spatial Variation In Abundance and Species Composition- (아산만 저어류 -III. 정점간 양적 변동과 종조성-)

  • LEE Tae Won
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.5
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    • pp.438-445
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    • 1993
  • Spatial and seasonal variations of community structure of demersal fishes in Asan Bay were studied using seasonal samples collected by an otter trawl from autumn 1991 to summer 1992. For each sampling station, three trawl hauls were completed to obtain a reliable sample. Of 34 species identified, Cynoglossus joyneri, Johnius belengeri, Zoraces gillii and Thrissa koreana accounted for $93\%$ of the individuals collected. The former three dominant species were more abundant on the finer sediment of the inner bay than on the sandy bottom of the outer bay. Spatial variation of community structure of demersal fishes was analysed by principal component analysis using rank correlation. The community structure did not show a spatial difference, but a clear seasonal trend. This distribution pattern seems to be related significantly to the seasonal temperature fluctuation and to the active mixing of the water by strong tidal current of the bay.

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Seasonal Fluctuation of Zooplankton Community in Asan Bay, Korea (아산만 동물플랑크톤 군집의 계절변화)

  • CHOI Keun-Hyung;PARk Chul
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.26 no.5
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    • pp.424-437
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    • 1993
  • About three fourths of total variability of zooplankton in Asan Bay was associated with season and the difference between inner bay and outer bay was relatively small. However, the differences in percent compositions of major taxa at inner bay and outer bay increased gradually with time, suggesting the change of ecosystem in this bay due to the human exploitation such as reclamation. Seasons of maximum abundances were different among the taxa but consistent for each taxon throughout the three survey years. Calanus sinicus and Acartia bifilosa showed maximum abundance in spring. Sagitta crassa, Paracalanus parvus, A. pacifica, Tortanus spinicaudatus, Corycaeus affinis and Decapoda larva were most abundant in summer. Labidocera euchaeta and Bivalve larva appeared most abundantly in fall. But in winter no taxon showed maximum. In general, low abundance with many species in fall, low abundance and few taxa in winter, increase in both number of taxa and abundance in spring, and high abundance and many taxa in summer were observed. A hypothesis for the observed patterns was suggested although more evidences were needed to support this.

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Contents of Histamine, Total Volatile Bases and Trimethylamine in Fresh Fish and Canned Fish Products (생선과 생선통조림의 히스타민, 전휘발성염기 및 트리메틸아민 함량)

  • LEE S. Y.;BYUN S. M.;CHUNG J. R.;PARK D. Y.
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.18 no.3
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    • pp.214-218
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    • 1985
  • A survey was made to determine seasonal variation of histamine, total volatile base and trimethylamine levels in a number of fresh fish and canned fish products as available through present distribution systems in Seoul area in order to assess potential danger of histamine poisoning related problems. Data obtained indicated that those products as available in present distribution systems should present no potential danger of histamine poisoning related problems.

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