• International Journal of Industrial Entomology and Biomaterials
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• 제26권2호
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• pp.74-80
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• 2013

Three new Multi ${\times}$ Bi combinations M.Con.4 ${\times}$ (SK6 ${\times}$ SK7), M.Con.4 ${\times}$ NB4D2 and Nistari ${\times}$ (SK6 ${\times}$ SK7) were studied in five seasons i.e. during the period of $18^{th}$ June - $12^{th}$ July, $30^{th}$ August - $23^{rd}$ September, $3^{rd}$ November - $2^{nd}$ December, $29^{th}$ January- $2^{nd}$ March and $30^{th}$ March-$25^{th}$ April with one control Nistari ${\times}$ NB4D2 considering nine reeling characteristics along with shell percent and cocoon yield per 100 disease free layings (DFLs) to establish the seasonal effect on all the parameters. Results reveal that all the characters performed well in November-December. Highest yield per 100 DFLs was recorded during November-December in all combinations showing >60 kg yield. Higher correlation of yield/100 DFLs with filament length, non-breakable filament length, denier, raw silk percent, reelability percent and recovery percent was recorded in all combinations of Multi ${\times}$ Bi considered in this study. Variability observed among four combinations indicates the effect of different temperature and humidity of different seasons on expression of different traits. The results indicate that there is significant relationship of raw silk percent with reelability percent, recovery percent and evenness. Reelability percent showed higher correlation with recovery percent. It was observed that neatness was positively correlated with evenness. The overall performance of the newly evolved combinations with regard to productivity and reeling characteristics is discussed emphasizing their utilization at commercial level.

• 한국습지학회지
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• 제13권3호
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• pp.471-479
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• 2011

증발산은 토양 표면에서 일어나는 증발 과정과 식물의 광합성으로 인해 발생하는 증산 작용을 포함한 수문 기상인자로 수문 순환과정에서 중요한 역할을 차지한다. 현재 국내외에서는 증발산을 산정하고 공간적인 거동을 파악하기 위한 연구가 활발히 진행되고 있지만 특정 지역에서의 토지 피복의 차이나 식생으로 인해 거동을 이해하는데 많은 제약이 따른다. 본 연구에서는 고해상도의 영상을 제공하는 Landsat 위성이 기반이 되는 원격탐사 기반 에너지 수지 모형인 Mapping EvapoTRanspiration with Internalized Calibration (METRIC) 모형과 MODerate resolution Imaging Spectroradiometer (MODIS) 위성 기반의 Penman-Monteith 알고리즘으로 산정된 증발산의 공간 분포를 비교하였다. 토지 피복별로 분류한 후 두 공간 분포를 비교하여 침엽수림과 활엽수림에서 가장 높은 상관관계를 갖는 것을 확인하였고 두 모형에 대한 적용성이 높음을 알 수 있다. 본 연구를 바탕으로 원격탐사 기반 고해상도 증발산 지도를 제작하여 시공간적 변동성과 계절 변화에 따른 거동을 파악할 수 있을 것이다.

• 한국지구과학회지
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• 제27권7호
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• pp.804-815
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• 2006

Meteorologists define a drought as a period of common dry weather. This may sound straightforward, but it is not so in reality. In this study, we attempted to identify meteorological drought conditions over South Korea. To evaluate the temporal and spatial variability of drought, we calculated two commonly used drought indices, the percent of normal precipitation (PNP) and the Palmer drought severity index (PDSI) calculated from fifty-eight meteorological stations below the Korean Meteorological Administration (KMA). The yearly precipitation has been growing gradually, and the amplitude between maximum and minimum also grow more explicitly from 1960's. According to the analysis of percentile anomaly of monthly precipitation, major drought duration was $1927{\sim}1929,\;1937{\sim}1939,\;1942{\sim}1944,\;1967{\sim}1968,\;1976{\sim}1977,\;1982{\sim}1983,\;1988,\;and\;1994{\sim}1995$. The severe drought occurred most frequently in Mokpo, Daegu, Jeonju, Busan, and Gangneung; it tended to occur more frequently in south sector than in mid sector of Korea and in south west sector than in south east sector. According to the analysis of seasonal distribution, extreme droughts occurred frequently in winter at Seoul, Gangneung, Jeonju, Daegu, and Busan. Severe droughts in summer were formed frequently at Seoul, Gangneung, and Mokpo, while that for spring at Jeonju, Daegu, and Busan. The results of PDSI distribution for the $1994{\sim}1995$ drought period were one of the most severe and widely spreaded droughts; it occurred most frequently in the south sector of South Korea. The comparison of time series between PDSI and Normal Percent showed that they exhibit a strong compatibility for the entire study period; it implies that both drought indices are useful method to indicate drought severity.

• 대한지리학회지
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• 제39권5호
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• pp.711-721
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• 2004

기상과 관련된 재해의 직접 원인이 되는 극한 기후 사상의 발생 빈도 및 강도의 변화 경향을 파악하는 것이 된 연구의 목적이다. 일최저기온, 일최고기온, 일강수량 자료를 이용하여, 10개 기후 변화 지시자를 산출하였다. 그 변화 경향의 공간 분포를 파악하였다. 일최저기온을 이용하여 산출된 온난야의 발생 빈도는 한반도에서 증가하는 추세를 나타냈고. 최저기온의 증가로 인하여 서리일수는 감소하고 생장기간은 증가하였다. 매해의 일최저기온과 일최고기온의 차로 산출되는 연극한기온교차는 최고기온은 변화하지 않았지만. 최저기온의 증가로 인하여 감소하고 있다. 강수와 관련된 지시자들은 기온 관련 지시자에 비하여 변화 경향이 뚜렷하지 않지만, 무강수일수의 한반도 시계열은 감소하는 경향이 나타났고, 호우지수로 분류될 수 있는 강수강도는 증가하고 있다.

• 한국수산과학회지
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• 제49권3호
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• pp.385-392
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• 2016

Seasonal variability in the algal community structure of intertidal zones was examined at six study sites in Marine National Parks, on the western and southern coasts of Korea from March to November 2015. A total of 193 species of algae, comprising 27 green, 40 brown and 126 red algae, were identified. Algal biomass averaged 101.50 g dry wt./m² with a maximal at Tonggae (168.12 g dry wt./m²) and minimum at Haseom (54.49 g dry wt./m²). The dominant seaweeds by biomass were Sargassum thunbergii at five sites (Tonggae, Haseom, Namdongri, Ando amd Sinjeonri), and S. fusiforme at Soando. Community indices measured as follows: dominance index (DI), 0.31–0.69; richness index (R), 7.30–11.43; evenness index (J'), 0.33–0.49; and diversity index (H'), 1.15–1.86. As evaluated using community indices and environmental states, the EEI (Ecological Evaluation Index) of the Marine National Park was “normal”. The present results indicate that seaweed community structures and indices could be used to evaluate the environmental status of coastal ecosystems.

• 한국수산과학회지
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• 제50권1호
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• pp.55-64
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• 2017

Seasonal variability in algal community structure was examined at the intertidal zones of five study sites on the Taean Peninsula, on the western coast of Korea, from February 2014 to November 2015. A total of 118 species of marine algae, comprising 17 green, 24 brown and 77 red algae, were identified. The maximum number of species was observed at the Mohang site (75 species), and the minimum at the Yeonpo site (46 species). The seaweed biomass was $160.24g\;dry\;wt./m^2$ on average, and was maximal at Uihang ($519.04g\;dry\;wt./m^2$) and minimal at Yeonpo ($19.03g\;dry\;wt./m^2$). Based on biomass, the dominant seaweeds at Taean peninsula were Sargassum thunbergii and Corallina pilulifera. Community indices were as follows: richness index (R), 3.21-5.01; evenness index (J'), 0.33-0.38; and diversity index (H'), 0.90-1.12. Based on evaluation of the environmental states by the community indices, the ecological evaluation index (EEI) of Taean peninsula was "moderate". The overall species and biomass of seaweeds decreased after the oil spill. However, Hakampo previously showed a similar algal community structure. In conclusion, the algal community was temporarily affected by the oil spill, but rapidly recovered.

• Ocean and Polar Research
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• 제31권1호
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• pp.11-29
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• 2009

Variability of sea surface temperature (SST) in the Japan/East Sea (JES) was studied using complex empirical orthogonal function (CEOF) analysis. Two daily data sets were analyzed: (1) New Generation 0.05o-gridded SST from Tohoku University, Japan (July 2002-July 2006), and (2) 0.25o-gridded SST from the Japan Meteorological Agency (October 1993-November 2006). Linkages with wind stress curl were revealed using 6-h 1o-gridded surface zonal and meridional winds from ancillary data of the Sea- WiFS Project, a special National Centers for Environmental Prediction/National Center for Atmospheric Research (NCEP/NCAR) product (1998-2005). SST anomalies (SSTA) were obtained by removing the seasonal signal, estimated as the leading mode of the CEOF decomposition of the original SST. Leading CEOF modes of residual SSTA obtained from both data sets were consistent with each other and were characterized by annual, semiannual, and quasi-biennial time scales estimated with 95% statistical significance. The Semiannual Mode lagged 2 months behind the increased occurrence of the anticyclonic (AC) wind stress curl over the JES. Links to dynamic processes were investigated by numerical simulations using an oceanic model. The suggested dynamic forcings of SSTA are the inflow of subtropical water into the JES through the Korea Strait, divergence in the surface layer induced by Ekman suction, meridional shifts of the Subarctic Front in the western JES, AC eddy formation, and wind-driven strengthening/weakening of large-scale currents. Events of west-east SSTA movement were identified in July-September. The SSTA moved from the northeastern JES towards the continental coast along the path of the westward branch of the Tsushima Current at a speed consistent with the advective scale.

• Journal of Korean Society for Atmospheric Environment
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• 제23권E1호
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• pp.1-9
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• 2007

In Korea, there is only a limited amount of information currently available on the levels of airborne bacteria and fungi of cattle sheds, although certain portions of people are potentially exposed to these bioaerosols in cattle sheds. Accordingly, the current study measured them inside cattle sheds, inside and outside farmers' houses near the sheds, and/or inside residential houses far away from the sheds during winter, 2004 and summer, 2005. The airborne bacteria and fungi were detected in most samples in the cattle farmers' houses as well as in the cattle sheds. Aspergillus, Cladosporium, and Penicillium, which have been associated with adverse health effects, were three most prevalent fungal genera, and they took most of the total fungi (more than 69%). The microbial concentrations measured inside the cattle sheds were comparable to those in other reports. Nevertheless, the present arithmetic and geometric mean (GM) microbial concentrations exceeded the Korean guideline for total airborne bacteria at medical facilities ($800\;CFU\;m^{-3}$), the current GM residential indoor concentrations at houses, and the residential indoor levels reported in other countries. The present findings suggest the need for a strategy to reduce Korean cattle farmers' exposure to these microorganisms. In contrast to the microbes, it is suggested that the cattle shed is not an important microenvironment for $PM_{10}$ exposure. Two characteristics examined in this study (seasonal variation and summer survey period, i.e., temperature and humidity) were all important for the cattle farmers' occupational exposure to airborne microbes. The lack of constancy between highest and lowest concentrations of bioaerosols over the survey period further suggests the necessity of performing a long-term survey to better examine farmer exposure levels and their variability.

• 대기
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• 제18권4호
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• pp.507-524
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• 2008

In this paper, future climate changes over East Asia($20^{\circ}{\sim}50^{\circ}N$, $100^{\circ}{\sim}150^{\circ}E$) are projected by anthropogenic forcing of greenhouse gases and aerosols using coupled atmosphere-ocean general circulation model (AOGCM) simulations based on Intergovernmental Panel on Climate Change (IPCC) Special Report on Emissions Scenarios (SRES) B1, A1B and A2 scenarios. Before projection future climate, model performance is assessed by the $20^{th}$ Century (20C3M) experiment with bias, root Mean Square Error (RMSE), ratio of standard deviation, Taylor diagram analysis. The result of examination of the seasonal uncertainty of T2m and PCP shows that cold bias, lowered than that of observation, of T2m and wet bias, larger than that of observation, of PCP are found over East Asia. The largest wet bias is found in winter and the largest cold bias is found in summer. The RMSE of temperature in the annual mean increases and this trend happens in winter, too. That is, higher resolution model shows generally better performances in simulation T2m and PCP. Based on IPCC SRES scenarios, East Asia will experience warmer and wetter climate in the coming $21^{st}$ century. It is predict the T2m increase in East Asia is larger than global mean temperature. As the latitude goes high, the warming over the continents of East Asia showed much more increase than that over the ocean. An enhanced land-sea contrast is proposed as a possible mechanism of the intensified Asian summer monsoon. But, the inter-model variability in PCP changes is large.

• Ocean and Polar Research
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• 제23권2호
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• pp.141-160
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• 2001

The challenge of predicting the Japanese coastal ocean motivated Frontier Observational Research System for Global Change (FORSGC) and the Japan Marine Science and Technology Center (JAMSTEC) to start a multiyear observational programme in the upstream Kuroshio in November 2000. This field effort, the Kuroshio Observation Program (KOP), should enable us to determine the barotropic and baroclinic components of the western boundary current system, thus, to better understand interactions of the currents with mesoscale eddies, the Kuroshio instabilities, and path bimodality. We, then, will be able to improve modeling predictability of the mesoscale, seasonal, and inter-annual processes in the midstream Kuroshio near the Japanese main islands by using this knowledge. The KOP is focused on an enhanced regional coverage of the sea surface height variability and the baroclinic structure of the mainstream Kuroshio in the East China Sea, the Ryukyu Current east of the Ryukyu's, and the Kuroshio recirculation. An attractive approach of the KOP is a development of a new data acquisition system via acoustic telemetry of the observational data. The monitoring system will provide observations for assimilation into extensive numerical models of the ocean circulation, targeting the real-time monitoring of the Japanese coastal waters.