• 대한토목학회논문집
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• 제35권4호
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• pp.815-820
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• 2015

제주도의 효율적 수자원 관리 기반을 구축하기 위해서는 지표수의 유출 특성과 증발산량, 지하수 함양량, 지하수 유출량의 상호관계를 정확하게 제시할 필요가 있다. 이 중 식생에 의한 차단(interception)효과는 증발산량에 직결되는 영향 인자임에도 정량적 분석의 어려움 때문에 유역단위로 정량화된 사례는 드물다. Von Hoyningen-Huene (1981)이 엽면적지수와 차단저류량의 관계를 밝혔고, LAI는 차단, 증산의 핵심요소로 다양한 수문모형에 활용되고 있다. 본 연구에서는 Kozak et al. (2007)이 제시한 엽면적 지수(LAI: Leaf Area Index)에 따른 차단저류량의 관계식을 이용하여 한국형 유역수문모형 SWAT-K (Soil and Water Assessment Tool-Korea)내에 식생에 의한 차단량 산정모듈을 개선하였다. 제주도 천미천 유역을 대상으로 적용한 결과 천미천 유역의 차단증발량은 85~104mm로서 전체 증발산량(993~1062mm)의 약 8~11% 만큼 차지하는 것으로 분석되어 전체 물수지 성분에 영향인자로 고려되어야 할 것이다.

• 한국방재학회:학술대회논문집
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• 한국방재학회 2007년도 정기총회 및 학술발표대회
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• pp.595-598
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• 2007

Urban storm water collection and conveyance systems are critical components of the urban infrastructures. During a storm event, street grate inlets are usually loaded with debris by the first-flush runoff volume. Grate inlets are subject to clogging effects. Effective interception area of grate inlets was decreased by clogging. It also decreased the interception capacity of grate inlets and increased the inundation area in street. Therefore, it is necessary to analyze the clogging characteristics and interception capacity change by clogging for appropriate design and management of grate inlets. In this study, field survey was executed to investigate debris and clogging pattern of grate inlet in 9 areas. The clogging factor with consideration of urban area characteristics was estimated with the field survey results.

• 대한토목학회논문집
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• 제26권2B호
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• pp.179-186
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• 2006

빗물받이가 자갈, 토사 및 기타 유송잡물에 의하여 막히게 되면, 유입구의 순 면적이 감소하게 되므로 설치된 빗물받이는 제 기능을 다하지 못하여 도로의 침수피해를 가중시키는 요인이 된다. 그러므로 빗물받이의 합리적인 설계와 관리를 위하여 빗물받이의 막힘 현상을 분석할 필요가 있다. 본 연구에서는 8가지의 막힘 조건을 가진 $40{\times}50cm$ 규모의 빗물받이를 설치하여 도로의 종경사, 측구의 횡경사 및 막힘 정도를 변화시키면서 총 81회의 실험을 실시하였다. 실측자료를 분석한 결과 빗물받이 유입구가 연석방향으로 막힌 경우가 흐름방향으로 막힌 경우보다 차집효율이 현저하게 감소하였다. 막힘 조건을 가진 유입부에서도 도로의 종경사가 증가할수록 유속이 증가하여 물의 튐 현상(splash-over)이 크게 발생하여 빗물받이의 차집 효율을 감소시킨다. 또한 빗물받이의 설계 시 외국에서 일반적으로 채택되고 있는 막힘 정도가 50%일 경우에 도로의 종경사와 측구의 횡경사의 변화를 고려한 국내 빗물받이의 막힘계수는 0.25~0.65로 판단된다.

• 한국의류산업학회지
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• 제10권2호
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• pp.242-248
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• 2008

This study was aimed to find whether the Chelidonium majus which grows naturally in Korean soil and has a various medical ingredient is valuable as a natural dyeing material and to examine the functionality of Chelidonium majus extract. As the test result of dyeing colorfastness, colorfastness to sunlight was 1st grade for all the dyed fabrics. The colorfastness to laundry for discoloration showed from 1st to 4th grade and that for discoloration showed from 4th to 5th grade through all the dyed fabrics. Colorfastness to perspiration, rubbing, and drycleaning showed from 4th to 5th grade through all the dyed fabrics. In the result of antibiosis test, the dyed cotton fabric showed the bacteria reduction rate of 99.0% for Staphylococcus aureus and Escherichia coli evenly when washed one, three, and five times, The dyed silk fabric, when washed one, three, and five times, showed the bacteria reduction rate of 99.0% for Staphylococcus aureus, but didn't showed the significant bacteria reduction. As the test result of sun protection test, in the case of the cotton fabric which was dyed but don't use mordant, after one-time washing, S.P.F.(Sun Protection Factor) showed 20.4, the interception rate of UV-A showed 94.3%, and that of UV-B showed 95.2%. After five-time washing, S.P.F. showed 14.3, the interception rate of UV-A showed 90.0%, and that of UV-B showed 93.2%. In the case of the silk fabric which was dyed but don't use mordant, after one time washing, S.P.F. showed 30.5, the interception rate of UV-A showed 95.9%, and that of UV-B showed 96.9%, after five-time washing, S.P.F. showed 31.0, the interception rate of UV-A showed 95.6%, and that of UV-B showed 96.7%.

• Journal of Radiation Protection and Research
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• 제23권4호
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• pp.219-227
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• 1998

온실내에서 $^{85}Sr$, $^{103}Ru$, $^{134}Cs$의 혼합용액을 배추의 생육중 다섯 차례에 걸쳐 엽면에 분무처리 하였다. 처리된 핵종이 작물체에 의해 차단되는 정도는 핵종간에 차이가 없었고 처리시기가 수확기에 가까울수록 점점 증가하였다. 측정된 차단계수의 최고치는 0.87이었다. 작물체에 침적한 핵종의 수확시 잔류율은 처리시기에 따라 전체잎의 경우 $^{85}Sr$가 $16{\sim}58%$, $^{103}Ru$이 $15{\sim}73%$, $^{134}Cs$가 $33{\sim}64%$ 였고 속잎(6장의 겉잎 제거)의 경우 각각 $2{\sim}35%$, $0.4{\sim}46%$ 및 $14{\sim}40%$였다. 강우가 방사성 핵종의 환경제거 정도를 결정하는 데 중요한 역할을 한다는 것이 확인되었다. 배추의 생육후기 처리시 상단부를 묶었을 때 차단계수와 속잎 잔류율이 서너배씩 감소되었다 본 연구결과는 배추의 생육중 사고방출시 배추내 핵종농도 예측 및 대책수립에 활용될 수 있다.

• 한국조명전기설비학회:학술대회논문집
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• 한국조명전기설비학회 2001년도 학술대회논문집
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• pp.59-64
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• 2001

Transient in an electrical system are generated by lightning and switching. This paper presents analysis of switching and lightning surge, and means of limiting the voltage magnification transient for high voltage power systems by using EDSA's EMTAP software package. One means of limiting the voltage magnification transient is to convert the end-user power factor correction banks to harmonic filters. An inductance in series with the power factor correction bank was used to decrease the transient voltage at the customer bus to acceptable levees. The interception of the impulse from the phase wire is fairly straight forward by properly installed surge arresters. The simulation shows that the addition of the surge arrester at the customer location can achieve a substantial reduction of the transient magnitude.

• 플랜트 저널
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• 제9권4호
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• pp.26-30
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• 2013

유동가속부식에 의해 배관이 파손된 500 MW급 A 복합발전소 배열회수보일러 저압증기발생기 배관을 모델로 삼아 배관급수 내의 용존산소 부족이 유동가속부식의 주요 원인임을 도출하고 용존산소를 증가시키기 위해 적용된 하이드라이진 차단 수처리에 대한 적용효과를 분석하였다. 수처리 적용 1년 후 급수의 용존산소는 0.15 ppb에서 3~5 ppb로 상승되고, 산화환원전위도 -245 mV에서 170 mV로 산화성으로 상승되었다. 또한 유동가속부식에 의한 부식생성물인 철분함유량은 18.5 ppb에서 5~7 ppb로 감소되었다. 따라서 하이드라이진 차단 수처리로 급수의 용존산소가 증가되며 유동가속부식에 의한 배관의 부식생성물인 철분함유량이 감소됨을 확인하였다.

• Environmental Engineering Research
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• 제22권1호
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• pp.87-94
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• 2017

This study was conducted to determine the effect of the climate change to the level of groundwater recharging. This research was conducted on the watershed of Bangga by using the Soil Water Balance of MockWyn-UB model. Input data compose of evapotranspiration, monthly rainfall, watershed area, canopy interception, heavy rain factor and the influence of climate change factors (rainfall and temperature). The conclusion of this study indicates that there is a decreasing trend in annual groundwater recharge observed from 1995 to 2011. The amount of groundwater recharge varied linearly with monthly rainfall and between 3% to 25% of the rainfall. This result implies that rain contributed more than groundwater recharge to runoff and evaporation and the groundwater recharge and Bangga River discharge depends largely on the rainfall. In order to increase the groundwater recharge in the study area, reforestation programmes should be intensified.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2002년도 하계학술대회 논문집 A
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• pp.259-261
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• 2002

Recently, according to the spread of semiconductor applied technology like motor speed control contrivance, power conversion installation and so on, harmonic ingredients occurred in switching operation flow into a distribution system and increase voltage distortion of distribution system and bring on obstacles like damage, lowering of capability, false operation and so on of various electrical installation. So, in order to consider a countermeasure to limit occurrence quantity of harmonic source, harmonic interception and others, precision measurement and analysis on voltage, current, power, power factor, the each ingredient of harmonic order, the percentage of total harmonic distortion and so forth are needed. In this paper monitoring system to measure and analyze power quality connected with power harmonics was developed and it's performance is verified by measuring and analyzing three-phase voltage and current of R, S, T in the three-phase and four-wire system using the developed measurement system.

• 한국수자원학회:학술대회논문집
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• 한국수자원학회 2012년도 학술발표회
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• pp.200-204
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• 2012

In engineering hydrology, an estimation of precipitation loss is one of the most important issues for successful modeling to forecast flooding or evaluate water resources for both surface and subsurface flows in a watershed. An accurate estimation of precipitation loss is required for successful implementation of rainfall-runoff models. Precipitation loss or hydrological abstraction may be defined as the portion of the precipitation that does not contribute to the direct runoff. It may consist of several loss elements or abstractions of precipitation such as infiltration, depression storage, evaporation or evapotranspiration, and interception. A composite loss rate model that combines four loss rates over time is derived as a lumped form of a continuous time function for a storm event. The composite loss rate model developed is an exponential model similar to Horton's infiltration model, but its parameters have different meanings. In this model, the initial loss rate is related to antecedent precipitation amounts prior to a storm event, and the decay factor of the loss rate is a composite decay of four losses.