• 대한원격탐사학회지
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• 제21권1호
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• pp.31-49
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• 2005

We first review some history of the Global Geodynamics Project (GGP), particularly in the progress of ground-satellite gravity comparisons. The GGP Satellite Project has involved the measurement of ground-based superconducting gravimeters (SGs) in Europe for several years and we make quantitative comparisons with the latest satellite GRACE data and hydrological models. The primary goal is to recover information about seasonal hydrology cycles, and we find a good correlation at the microgal level between the data and modeling. One interesting feature of the data is low soil moisture resulting from the European heat wave in 2003. An issue with the ground-based stations is the possibility of mass variations in the soil above a station, and particularly for underground stations these have to be modeled precisely. Based on this work with a regional array, we estimate the effectiveness of future SG arrays to measure co-seismic deformation and silent-slip events. Finally we consider gravity surveys in volcanic areas, and predict the accuracy in modeling subsurface density variations over time periods from months to years.

• 한국자원식물학회지
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• 제21권3호
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• pp.171-177
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• 2008

Variations in antioxidant capacity of leaves and characteristics of seed germination among five Hibiscus hamabo populations in Korea were evaluated. While the leaves of H. hamabo from Shincheon contained highest Na concentration, those from Hado and Ohzo does lowest. MDA content and SOD activity didn't show significant difference among populations, but total protein and anthocyanin content were significantly different among five populations. The filled seed rates of five populations were ranged from 92.0 to 98.7%, and the moisture contents of seeds from Shinyang and Soando were lower than that of R. syriacus (5.18%). The fresh weights of H. hamabo from Hado and Ohzo were the highest and those of seeds from Shinyang and Soando were the lowest. Significant variations among H. hamabo populations were detected for all seed germination characters: percentage of germination, average germination time and germination rate and uniformity. SOD activities of seeds from Onpyoung and Soando were the highest of five populations, and total protein concentrations of seeds in Ohzo and Shinyang populations were higher than those of other populations. H. hamabo is considered exposed to salt stress and all characteristics of seed germinations were inferior to other species.

• 조명전기설비학회논문지
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• 제14권1호
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• pp.53-58
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• 2000

본 논문에서는 에폭시 복합 절연재료를 옥외에서 사용할 경우 수분의 영향을 고찰하기 위하여 비등홉수조건에 서 기계적 강도와 절연파괴강도의 변화를 측정하였다. 또한 내습성을 개선하기 위한 방법으로 이전에 보고하였던 상호침입망목 수법을 도입하여 그 효과를 비교 검토하였다. 두 종류의 모체수지에 충진재를 0, 50, 100 [phr] 첨가하여 총 6종류의 시편을 제작하였다. 그 결과, 비등흡수시간과 충진재 함량이 증가함에 따라 수분 흡수율이 증가되었고, 기계적 강도와 절연파괴강 도가 저하됨올 확인하였다. 반면 상호침입망목 시편의 경우에서는 접착강도의 개선에 의하여 홉수율이 낮아지고, 기계적 강도와 절연파괴 강도의 저하율이 완화됨을 확인하였다.

• 한국환경과학회지
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• 제7권1호
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• pp.96-103
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• 1998

To study the optimum conditions of composting with industrial wastewater sludge, the variations of temperature and $CO_2$ generation amount during the composting periods were investigated. The conditions were that industrial wastewater added to bulking agents such as sawdust and rice hull was used, and differently treated with microorganism seeding or not, initial C/N ratios, air flow rate and initial moisture contents, respectively. The results were summarized as follows : Seeding 5% of microorganism was higher the temperature than not seeding. And using sawdust as bulking agents, and adjusting 30~40 of Initial C/N ratio, 200ml/l.min. of k flow rate and 67~68% moisture contents were higher the temperature than any other conditions. Seeding 5% of microorganisms was higher $CO_2$ generation amount than not seeding. And that was much in the order of 7~40, 30~34 and 22~23 of initial C/N ratio. Judging from the results, it should be considered that the optimum conditions in the composting of industrial wastewater sludge were seeding of 5% microorganisms, and adjusting 30~34 of Initial C/N ratio, 200ml/l min. of air flow rate and 67~68% of Intitial moisture contents. The contents of inorganic matters and C/N ratio during the composting periods at optimum condition were a little Increased. and heavy metals contents after composting were lower than standard for fortllizer.

• 한국방재학회 논문집
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• 제10권3호
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• pp.85-90
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• 2010

본 연구에서는 우리나라 산림의 주요 분포 수종 가운데 참나무류의 대표 수종인 굴참나무의 생엽을 대상으로 월별(6월~10월) 연소특성을 고찰하였다. 함수율은 114%~155% 정도였으며, 10월의 생엽은 수분함유량과 무염착화온도가 가장 낮은 것으로 나타났다. 7월 생엽은 27s 정도의 가장 빠른 시간에 발염착화 되었으며, 9월의 생엽은 105s 정도로 가장 오랜 시간동안 화염이 지속되고 총열방출량도 가장 높은 것으로 나타났다. 총열방출량과 총연기방출량은 모두 월별로 차이를 보였는데 6월부터 10월까지 점차 증가하는 경향을 나타냈다. 최대연기밀도는 10월의 생엽이 약간 높은 것으로 나타났지만 월별 차이는 거의 없었으며, 7월의 생엽은 다른 생엽들보다 상대적으로 빠른 시간인 795s에 최대값에 도달하는 것으로 나타났다.

• 한국환경과학회지
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• 제20권9호
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• pp.1165-1182
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• 2011

The evaluation of potential submarine groundwater is an important research topic for exploring an alternative water resource. Two different approaches, water budget analysis and Rn mass balance method, were employed to investigate the annual variation of submarine groundwater discharge in 2010 at a marine watershed located at the south-eastern part of Korean Peninsula. In order to obtain reliable hydrological data during study period, temporal and spatial variations of rainfall and soil moisture had been collected and hydro-meterological data such as temperature, humidity and wind speed were collected The runoff response was simulated using SCS-CN method with spatial distributions of landuse and soil texture from GIS analysis. Six different methods were used to estimate the monthly variation of evapotranspiration and field measurements of soil moisture were used to account for the infiltration. Comparisons of infiltration and surface runoff between simulation and water balance with measurements showed coincidence. The water budget analysis and Rn mass balance method provide mean daily submarine groundwater as 5.35 and 4.07 $m^3/m/day$ in 2010, respectively.

• 한국식품과학회지
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• 제19권1호
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• pp.1-4
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• 1987

1984년(年) 5월(月)부터 1985뚜 4월(月)까지 1년간(年間) 천연산(天然産) 잉어 및 붕장어의 계절에 따른 어묵 원료적성(原料適性)을 실험한 결과. 잉어는 일반성분(一般成分)의 계절변화가 거의 없었으며 년중(年中) 어묵의 품질이 모두 양호하였다. 붕장어는 수분과 조지방의 년중(年中) 변화복(變化福)이 각각 $61.0{\sim}76.6%$, $5.4{\sim}20.8%$로써 변화가 컸고 $9{\sim}2$월(月)의 것은 $3{\sim}8$월(月)의 것보다 수분은 적고 지방함량은 많았으며 이 시기(時期)에 어획(漁獲)한것으로 만든 어묵 가공제품(加工製品)은 다른 때의 것보다 품질이 우수하였다. 단백질, 회 및 탄수욕물 함량은 년중(年中)거의 변화가 없었다.

• 생명과학회지
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• 제13권6호
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• pp.757-763
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• 2003

본 시험은 율무재배에 적절한 토양수분조건과 파종기 및 질소시비방법를 구명하기 위하여 토양수분은 자연강우에 의존하는 밭 상태의 대조구와 인위적으로 포화상태를 유지시키는 관개구로 구분하여 처리하였고, 파종기는 6월 10일, 6월 20일, 6월 30일에 각각 파종하였으며, 질소시비는 전량기비와 파종기 및 출수기에 50%씩 분시하는 방법 등으로 하여 율무의 생육과 수량 및 수량구성요소의 변화를 시험한 결과는 다음과 같다. 파종기가 빠를수록 출수 및 성숙기가 빨랐고, 출수일수는 파종기가 지연될수록 감소하는 경향이었으며 성숙일수는 처리간 차이가 인정되지 않았다. 토양수분은 관개구에서 자란 율무가 대조구에서 자란 율무에 비하여 간장과 경태는 컸으며, 파종기가 빠를수록 현저하게 증가하였고, 분얼수도 대조구에 비해 관개구에서 현저한 증가를 보였으며 만파할수록 분얼수가 감소하였다. 지상과 지하부의 생육은 관개구가 대조구에 비하여 왕성한 생육을 보였으며, 파종기가 지연될수록 현저하게 감소하는 경향이었다 개엽 광합성속도는 대조구에 비하여 관개구가 훨씬 높았으며, 엽고병 발병율은 관개구가 낮았다. 관개구가 대조구보다 천립중이 무거웠고 수량은 증가하였으며, 불임율은 관개구가 대조구보다 낮았고, 파종기가 빠를수록 천립중이 무거웠고 수량도 증가하였다.

• 콘크리트학회논문집
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• 제12권2호
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• pp.99-107
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• 2000

This research investigates experimentally an effect on the properties of the high flowing concrete to be poured in the under-ground slurry wall of Inchon LNG receiving terminal(#213,214-TK) according to variations of concrete materials. Variables for sensitivity test were selected items as followings. 1) Concrete temperature (3cases), 2) Unit water (5cases), 3) Fineness modulus of fine aggregate (5cases), 4) Particle size of lime stone powder (3cases), 5) Replacement ratio of blast-furnace slag (4cases) and 6) Addition ratio of high range water reducing agent (5cases). And fresh conditions of the super flowing concrete should be satisfied with required range including slump flow(65$\pm$5cm), 50cm reaching time of flow(4~10sec), V-lot flowing time(10~ 20sec), U-box height(min. 300mm) and air content(4$\pm$1%). As results for sensitivity test, considered flow-ability, self-compaction and segregation resistance of the high flowing concrete, material variations and conditions of fresh concrete should be satisfied with the range as follwings. 1) Concrete temperature are 10~2$0^{\circ}C$(below 3$0^{\circ}C$), 2) Surface moisture of fine aggregate is within $\pm$ 0.6%, 3) Fineness modulus of fine aggregate is 2.6$\pm$0.2, 4)Replacement ratio of blast-furnace slag is 45~50% and 5) Addition ratio of high range water reducing agent is within 1%. Based on the specification for quality control, we successfully finished concrete pouring on the under-ground slurry wall having 75,000㎥(#213,214-TK) and accumulated real date in site.

• Proceedings of the National Institute of Ecology of the Republic of Korea
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• 제1권1호
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• pp.58-67
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• 2020

Terrestrial ecosystems influence climate change via their climate regulation function, which is manifested within the carbon, water, and energy circulation between the atmosphere and surface. However, it has been challenging to quantify the climate regulation of terrestrial ecosystems and identify its regional distribution, which provides useful information for establishing regional climate-mitigation plans as well as facilitates better understanding of the interactions between the climate and land processes. In this study, a land surface model (LSM) that represents the land-atmosphere interactions and plant phenological variations was introduced to assess the contributions of terrestrial ecosystems to atmospheric warming or cooling effects over East Asia over the last half century. Three main climate-regulating components were simulated: net radiation flux, carbon exchange, and moisture flux at the surface. Then, the contribution of each component to the atmospheric warming or cooling (negative or positive feedback to the atmosphere, respectively) was investigated. The results showed that the terrestrial ecosystem over the Siberian region has shown a relatively large increase in positive feedback due to the enhancement of biogeochemical processes, indicating an offset effect to delay global warming. Meanwhile, the Gobi Desert shows different regional variations: increase in positive feedback in its southern part but increase in negative one in its eastern part, which implies the eastward movements of desert areas. As such, even though the LSM has limitations, this model approach to quantify the climate regulation is useful to extract the relevant characteristics in its spatio-temporal variations.