• 대한토목학회논문집
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• 제7권3호
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• pp.55-60
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• 1987

도로포장용(道路鋪裝用) 골재(骨材)로 슬래그를 사용할 때에 우수(雨水)와의 접촉에 의하여 생성되는 침출수(浸出水)에 의한 지하수(地下水)와 농작물에 대한 영향과 강재(鋼材)의 부식(腐蝕)여부를 검토하였다. 슬래그만의 침출실험결과(浸出實驗結果)와 침출수(浸出水)의 토양투과(土壤透過)에 의한 정상변화를 볼 때에 슬래그는 지하수(地下水)의 pH와 $SO_4^=$, $Ca^{{+}{+}}$, $Mg^{{+}{+}}$ 등의 농도를 높여 줄 가능성이 있는 것으로 나타났으며 pot 실험(實驗)을 통하여 볼때에 알타리무우의 생육(生育)에는 나쁜 영향을 주지 않는 것으로 나타났다. 부식촉진실험결과(腐蝕促進實驗結果)에 따르면 침출수(浸出水)와 강재(鋼材)의 접촉 초기에는 부식속도(腐蝕速度)가 매우 빠르나 $50^{\circ}C$에서 약 50 일후에는 부식정도가 일반토양(一般土壤)의 경우와 유사하게 되었다.

• Smart Structures and Systems
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• 제20권2호
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• pp.231-246
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• 2017

A recent work by the authors has demonstrated the feasibility of scour evaluation for Kao-Ping-Hsi Cable-Stayed Bridge simply based on ambient vibration measurements. To further attain the goal of scour monitoring, a key challenge comes from the interference of several environmental factors that may also significantly alter the pier frequencies without the change of scour depth. Consequently, this study attempts to investigate the variation in certain modal frequencies of this bridge induced by several environmental factors. Four sets of pier vibration measurements were taken either during the season of plum rains, under regular summer days without rain, or in a period of typhoon. These signals are analyzed with the stochastic subspace identification and empirical mode decomposition techniques. The variations of the identified modal frequencies are then compared with those of the corresponding traffic load, air temperature, and water level. Comparison of the analyzed results elucidates that both the traffic load and the environmental temperature are negatively correlated with the bridge frequencies. However, the traffic load is clearly a more dominant factor to alternate the identified bridge deck frequency than the environmental temperature. The pier modes are also influenced by the passing traffic on the bridge deck, even though with a weaker correlation. In addition, the variation of air temperature follows a similar tendency as that of the passing traffic, but its effect on changing the bridge frequencies is obviously not as significant. As for the effect from the alternation of water level, it is observed that the frequency baselines of the pier modes may positively correlate with the water level during the seasons of plum rains and typhoon.

• 건축역사연구
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• 제16권3호
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• pp.7-20
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• 2007

A bridge is a space used as a passage. This space should be functional, solid, and beautiful. Since the beginning of human life, bridge architecture has given importance to function as a connection from one place to another. Stepping stones in the stream were the connections between divided spaces in the agricultural life, the bridge on the entrances of a town was the place for separation, expectation, and communication for people gathering around the community. Southern Chinese provinces such as Zhejiang, Hunan, Yunnan, and Guizhon is famous for it's spectacular scenary, and tribes like the 'Miao' and 'Dong' live in a cooperate community. The 'Dong' tribe is one of the 'Yue' genealogy where the people have settled down in this place in the days of 'Qin Shi Huang(Qin dynasty)'. As the population of the 'Dong' tribe growed, they used a bridge to connect town to town. The scale became larger with additional design, giving splendid achievement to bridge architecture. The 'Fungyu bridge' in Tongdao and 'Chungyang bridge' in Sanjiang are some fine examples. The Fungyu bridge could be defined as a bridge which blocks wind and rain, this has the same function as the lounge bridge in Taishun located in southern Zhejiang province. In Taishun, 5 minority races such as the 'Dong' and 'Miao' people have been living together as a clan society for centuries on mountains as high as 1000m following their own tradition. The 'Xiliu river' flowing thorough has a variety of bridges remaining in it's original form, and it is recently known as a museum of ancient bridges. The formation of the bridges in Tongdao and Taishun shows that it is different with the arch and straight bridges remaining in Korea. In this study, it is readjusting the base data, showing plan characteristics and describing the construction of the wooden structure above the bridge post.

• 한국작물학회:학술대회논문집
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• 한국작물학회 2017년도 9th Asian Crop Science Association conference
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• pp.281-281
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• 2017

Recently, global warming by greenhouse gas effect is getting danger and danger for human life and agriculture at present. In Indonesia, according to heavy rain in the agriculture land is often covered by excess water in result crop growth would be affected negative. This water stress triggers roots failure in anaerobic condition for upland crop because of limiting roots respiration. Chili pepper grows in upland sometimes in touch with waterlogging due to rainfall and /or over flow water from river in Indonesia. In this case, roots growing is inhibited by effect of shortage of oxygen at root cap. Therefore, the objective of this study is to observe the plant behavior in waterlogging using mahor local genotypes (Ferosa, Laris, Romario) in Sumatra. The experiment was kept by at 1cm depth water above the soil surface as a waterlogged treatment for ---days. As a result, waterlogging affected plant growth of chili negatively, especially for roots growth. Almost roots were getting bad and changed color for brown during waterlogging. A significant negative effect for nutrient absorption by roots was found in dry weight of all varieties during waterlogging. Dry weight of roots was decreased by 81.4% and 67.6%, and those of aerial part decreased by 74% and 67.2% compared with control in Ferosa and Romario at 1week after treatment. On the other hand, dry weight of roots was decreased only 35% in Laris. Therefore, Laris has a tolerance for waterlogging compared to with other varieties. Also, Laris in SPAD value was kept initial level during waterlogging however those of Ferosa and Romario decreased. Finally, due to impact of waterlogging, it may be the roots become failure because of less aerenchyma formation under anaerobic condition. We need confirm aerenchyma formation morphologically in the future.

• 한국지반환경공학회 논문집
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• 제13권9호
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• pp.75-82
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• 2012

본 논문은 2006년 태풍 에위니아와 빌리스의 영향으로 강원 영서지역에서 발생한 집중호우에 의한 산사태 발생 원인과 특성에 대하여 분석한 결과이다. 강원 영서지역은 편마암, 화강암이 풍화된 화강풍화토가 주를 이루는 지역으로 집중호우 시 산사태 및 토석류의 피해에 취약한 것으로 나타났으며 강우특성 분석결과, 산사태 발생은 3일 이내의 누적강우량과 밀접한 관계가 있었고 지역별 발생빈도의 차이는 최대시우량의 영향으로 나타났다. 영서지역에서 발생한 산사태 860개소에 대한 자료의 분석 결과, 파괴 형태는 전이형 슬라이드로 시작되어 유동성 슬라이드로 변화되는 양상을 보였으며, 사면 경사는 $20{\sim}30^{\circ}$ 사면 길이는 11~20m 범위, 사면 폭은 6~10m 범위에서 발생빈도가 높은 것으로 나타났고, 영서지역의 산사태는 사면 폭이 좁은 소규모 형태로 편마암, 화강암 지대의 산사태 전형으로 분석되었다.

• 대기
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• 제21권3호
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• pp.257-271
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• 2011

The aim of this study is to examine weather modification by urbanization and human activities. The characteristics of the urban heat island (UHI) and precipitation in Seoul metropolitan area of Korea are investigated to demonstrate that cities can change or modify local and nearby weather and climate, and to confirm that cities can initiate convection, change the behavior of convective precipitation, and enhance downstream precipitation. The data used in this study are surface meteorological station data observed in Seoul and its nearby 5 cities for the period of 1960 to 2009, and 162 Automatic Weather System stations data observed in the Seoul metropolitan area from 1998 to 2009. Air temperature and precipitation amount tend to increase with time, and relative humidity decreases because of urbanization. Similar to previous studies for other cities, the average maximum UHI is weakest in summer and is strong in autumn and winter, and the maximum UHI intensity is more frequently observed in the nighttime than in the daytime, decreases with increasing wind speed, and is enhanced for clear skies. Relatively warm regions extend in the east-west direction and relatively cold regions are located near the northern and southern mountains inside Seoul. The satellite cities in the outskirts of Seoul have been rapidly built up in recent years, thus exhibiting increases in near-surface air temperature. The yearly precipitation amount during the last 50 years is increased with time but rainy days are decreased. The heavy rainfall events of more than $20mm\;hr^{-1}$ increases with time. The substantial changes observed in precipitation in Seoul seem to be linked with the accelerated increase in the urban sprawl in recent decades which in turn has induced an intensification of the UHI effect and enhanced downstream precipitation. We also found that the frequency of intense rain showers has increased in Seoul metropolitan area.

• 한국수산과학회지
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• 제36권5호
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• pp.515-521
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• 2003

To understand interrelations between water quality and community structure of phytoplankton around the season of red tide outbreak, field surveys were conducted 10 times off the coast of Tongyeong from July to September in 2002. Because of heavy rain for 10 days, environmental conditions were changed and differed from the previous year, sustaining high nutrients and low salinity. During the surveyed period 48 species of 29 genera of phytoplankton were identified, and diatom and dinoflagellate was $51.8\%\;and\;38.0\%,$ respectively, At the time of bloom, cell counts of C. polykrikoides were outstanding but the number of species remarkably decreased. There were striking differences in dominant species among research stations before the bloom. Diatoms were the most dominant group in the whole study area in that period. Diversity and evenness index were highest just before outbreak of the red tides (2 Aug, 2002). During the bloom (4 Aug.), it decreased to the lowest value and then began to increase slowly. The result of PCA on water quality vs phytoplankton biomass showed that the land loads of nutrient may be the main cause of summer rally of phytoplankton biomass.

• 한국농림기상학회지
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• 제6권1호
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• pp.61-69
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• 2004

A long-term growth simulation was performed at 99 land units in Yeoncheon county to test the potential adaptability of each land unit for growing soybean cultivars. The land units for soybean cultivation(CZU), each represented by a geographically referenced land patch, were selected based on land use, soil characteristics, and minimum arable land area. Monthly climatic normals for daily maximum and minimum temperature, precipitation, number of rain days and solar radiation were extracted for each CZU from digital climate models(DCM). The DCM grid cells falling within a same CZU were aggregated to make spatially explicit climatic normals relevant to the CZU. A daily weather dataset for 30 years was randomly generated from the monthly climatic normals of each CZU. Growth and development parameters of CROPGRO-soybean model suitable for 2 domestic soybean cultivars were derived from long-term field observations. Three foreign cultivars with well established parameters were also added to this study, representing maturity groups 3, 4, and 5. Each treatment was simulated with the randomly generated 30 years' daily weather data(from planting to physiological maturity) for 99 land units in Yeoncheon to simulate the growth and yield responses to the inter-annual climate variation. The same model was run with input data from the Crop Experiment Station in Suwon to obtain a 30 year normal performance of each cultivar, which was used as a "reference" for evaluation. Results were analyzed with respect to spatial and temporal variation in yield and maturity, and used to evaluate the suitability of each land unit for growing a specific cultivar. A computer program(MAPSOY) was written to help utilize the results in a decision-making procedure for agrotechnology transfer. transfer.

• 한국습지학회지
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• 제12권3호
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• pp.165-175
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• 2010

급속한 산업화, 도시화 및 경제성장으로 다양한 개발사업이 발생하였다. 다양한 개발사업으로 인하여 각종 오염물질이 발생하였으며, 발생된 오염물질은 자연적으로 형성된 물순환 시스템이 아닌 인위적으로 형성된 물순환 시스템으로 인하여 하천 및 호소로 직접 유입되어 수질이 악화되고 있는 실정이다. 강우시 다양한 토지이용에서 발생하는 비점오염원이 큰 원인으로 나타나고 있다. 본 연구는 강우시 발생하는 비점오염물질 처리를 위한 저류 및 침투기능을 포함하는 한국형 비점오염저감시설인 Eco-Bio Filter (EBF)를 개발하고자 한다. EBF 시설은 저류 및 침투기능을 포함하며, EBF Test-bed를 공주대학교 천안 캠퍼스 내에 설치하여 다양한 강우사상에 대하여 모니터링을 수행하였다. 현재 모니터링 결과를 활용하여 기술의 문제점을 분석하고 개선하는 과정이 진행되고 있으며, 본 연구에서는 개선된 EBF 기술을 제시하였다. 오염물질별 저감효율을 분석한 결과, 입자상 물질, 질소, 인, 중금속에 대하여 70% 이상의 높은 저감효율을 나타내었다. 이러한 연구결과는 향후 국내 강우특성에 맞으며 도시의 생태를 확장할 수 있는 새로운 비점오염기술을 개발하는데 기초자료로 활용될 것이며, 저영향개발(LID) 중 하나가 될 것이다.

• 한국농공학회지
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• 제16권4호
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• pp.3555-3571
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• 1974

This experiment of which aim contribute to plan irrigation system so as to increase forage crop yields, was conducted to estimate evapotranspiration amount of forage crops and to find out system of consumed water in a pasture-ground. The results obtained by this study are as follows: 1. The general weather conditions which, were closely related to the evapotrannpiration of forage crops were nearly same as those of the average year with the exception that temperature of May and June were slightly low. 2. According to the investigation of potential evapotranspirations (P.E) or forage crops and its changes during growing periods, changes of tenday P.E. were high significant according to the harvesting period. P.E of Alfalfa of which yield was the largest was the biggest. Althrough the correlations between P.E. and meteorological factors were irregular oming to three-time harvesting, correlation between ten-day evapotraspiration amount and copper plated pan evaporation or solar radiation was high positive significant. 4. Predicting formulas of P.E. were led by weather factors, and also relatione between P.E. and weather factors were showed as figure. from the these formulas, P.E. may be calculated by weather factors. 5. Predicting formulas of P.E. were led by mean temperature and copper plated pan evaporation, and by mean temperature and solar radiation. As computed values and measured values showed in figure, these formulas were high signiflent. 6. In the total consumed soil water duration of 10 days which, was non-rain period from 12th to 21th of August, Alfalfa was the largest 48.1mm, second, Orchard grass 40.1mm and Fescue 37.6mm, and Ladino clover was the smallest 37.1mm, also, order of each forage crop yield amound. was same to the abov. Order of soil moisture extraction rate of soil layer of all the for forage crops dulation of ten-day was soil layer 1 which was largest, soil layer 2, 3, and 4 Reviewing the the first five-day and the second five day, in the first five-day, order of that of all the forage crops was same to the above, but in the second five-day, that of soil layer 2 or 3 was more than the of soil layer 1.