• 한국물환경학회지
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• 제26권5호
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• pp.860-870
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• 2010

Long term monthly monitoring data showed that the water quality of streams flowing into Lake Paldang has been improved by various strategy for water. However, the effect of quality on Lake Paldang is still insufficient because of nonpoint source from watershed. In order to evaluate quantifying methods for pollution source and make a suggestion on improvements, Storm Water Management Model (SWMM) was constructed by using data set from the water quality and streamflow monitoring network in the Kyoungan watershed for Total Maximum Daily Loads (TMDLs). Load duration curve (LDC) based on the result of the Kyoungan watershed SWMM indicated that the water quality criterion on $BOD_5$ was often exceeded in up-stream than down-stream. From flowrate-load correlation curve, SS load significantly increased as streamflow increases. 75.3% of streamflow and 62.1% of $BOD_5$ loads is discharged especially in the zone of high flows, but monitoring data set didn't provide proper information about the conditions and the patterns associated with storm events. Therefore, it is necessary to acquire representative data set for comparing hydrograph and pollutograph through monitoring experimental watershed and to establish methods for quantifying point and nonpoint source pollutant loads.

• 한국습지학회지
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• 제19권3호
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• pp.287-295
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• 2017

본 연구에서는 금호강의 수질 및 유량 자료를 이용하여 첨두수질에 따른 강우유출 특성을 분석하고 모니터링 및 오염원별 관리 시기 등의 비점오염 관리 방향을 도출하였다. 첨두수질농도(Peak Water Quality Concentration)는 강우유출수내 수질이 가장 높은 농도로 비점오염 관리 기준농도로 극값(Extremal value)을 활용하는 개념이다. 이 방법을 이용하여 누적강수량(총강수량), 첨두수질농도, 첨두수질농도까지의 누적강수량, 첨두수질농도까지의 시간, 첨두수질농도까지의 EMC 등의 평가인자를 검토하였고 장기간에 걸친 실측자료를 이용하여 비점오염원 강우유출특성을 분석하였다. 분석 결과를 통해 비점오염원을 관리하기 위한 적정 모니터링 및 관리방안을 제시하였다.

• Nuclear Engineering and Technology
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• 제20권2호
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• pp.132-136
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• 1988

지하수 오염물질의 이동모형 개발에 있어서 중요한 문제의 하나가 각각의 폐기물 저장용기 나 드럼을 독립된 선원으로 볼 것이냐 아니면 상응하는 합쳐진 선원으로 볼 것이냐 하는 문제이다. 본 논문에서는 포화된 다공성 매질에서의 분산된 선원에 대한 연구를 소개한다. 지하수의 유동이 있는 다공성 매질에서 평면상에 분산된 점 형태의 선원들을 가정하여 얻어 진 지하수내의 오염물질의 농도분포를 상응하는 크기를 가진 무한한 평면선원이나 하나의 점 선원을 농도분포들과 비교하였다. 본 연구의 결과로 다음의 세 영역을 찾아낼 수 있었다. 즉, (1) 선원에 가까운 관계로 인근 선원의 영향이 커서 각각의 선원들을 따로 고려한 모형을 사용하여야 하는 영역, (2) 선원에서 몇 미터 떨어진 지점으로부터 수백 내지 수천미터 떨어진 지점까지의 각각의 선원 대신 상응하는 유한한 평면 선원만이 정착한 결과를 얻게 하는 영역, (3) 선원으로부터 충분히 멀리 떨어져 있어서 상응하는 유한한 평면 선원만이 정확한 결과를 얻게 하는 영역이다

• 한국정밀공학회지
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• 제19권6호
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• pp.109-118
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• 2002

The vibrational intensity and the dynamic response of a compound vibratory system had been controlled actively by means of a feedforward control method. A compound vibratory system consists of a flexible beam and two discrete systems - a vibrating source and a dynamic absorber. By considering the interactive motions between discrete systems and a flexible beam, the equations of motion for a compound vibratory system were derived using a method of variation of parameters. To define the optimal conditions of a controller the cost function, which denotes a time averaged power flow, was evaluated numerically. The possibility of reductions of both of vibrational intensity and dynamic response at a control point located at a distance from a source were fecund to depend on the positions of a source, a control point and a controller. Especially the presence of a dynamic absorber gives the more reduction on the dynamic response but the less on the vibrational intensity than those without a dynamic absorber.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2002년도 추계학술대회 논문집
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• pp.554-557
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• 2002

This paper describes power potential field method for the collision-free path planning of stereo-vision based mobile robot. Area based stereo matching is performed for obstacle detection in uncertain environment. The repulsive potential is constructed by distributing source points discretely and evenly on the boundaries of obstacles and superposing the power potential which is defined so that the source potential will have more influence on the robot than the sink potential when the robot is near to source point. The mobile robot approaches the goal point by moving the robot directly in negative gradient direction of the main potential. We have investigated the possibility of power potential method for the collision-free path planning of mobile robot through various experiments.

• 한국지구물리탐사학회:학술대회논문집
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• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
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• pp.81-86
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• 2007

Spectral features of the seismic wave propagation from Odaesan Earthquake were evaluated based on the commonly treated random error between the observed data and the prediction values by the stochastic point-source ground-motion spectral model regarding the source, path and site effects. Radiation pattern of the error according to azimuth angle was found to be similar to the theoretical estimate. It was also observed that the spatial distribution of the errors was correlated with the geological map and the Q0 map which are indicatives of seismic boundaries.

• 대한조선학회지
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• 제12권2호
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• pp.13-34
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• 1975

Analytical solutions for the transient temperature distribution and quasi-static thermal stresses which arise in a thin circular disk of finite radius subjected to an instantaneous point source acting in its interior have been obtained. And the solutions have been extended to the case of a moving heat source with the aid of the Duhamel's superposition integral. The solutions given are in the form of double infinite serieses, and their numerical results have been compared with the experimental temperature histories. It can be found out that the theoretical histories of thermal stresses show a good agreement with the experimental results and the theoretical histories of thermal stresses show a good qualitative agreement with a physical phenomena. The solutions can be applied to the problems such as a flame hardening of the cylindrical machine elements and a circular patch welding or a circular cutting of the structural member.

• 천문학논총
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• 제27권4호
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• pp.165-169
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• 2012

We observed an area of 10 $deg^2$ of the Large Magellanic Cloud using the Infrared Camera (IRC) onboard AKARI. The observations were carried out using five imaging filters (3, 7, 11, 15, and $24{\mu}m$) and the prism disperser ($2-5{\mu}m$, ${\lambda}/{\Delta}{\lambda}{\sim}20$) equipped in the IRC. This paper presents an outline of the survey project and also describes very briefly the newly compiled near- to mid-infrared point source catalog. The $10{\sigma}$ limiting magnitudes are 17.9, 13.8, 12.4, 9.9, and 8.6 mag at 3.2, 7, 11, 15 and $24{\mu}m$, respectively. The photometric accuracy is estimated to be about 0.1 mag at $3.2{\mu}m$ and 0.06 - 0.07 mag in the other bands. The position accuracy is 0.3" at 3.2, 7 and $11{\mu}m$ and 1.0" at 15 and $24{\mu}m$. The sensitivities at 3.2, 7, and $24{\mu}m$ are roughly comparable to those of the Spitzer SAGE LMC point source catalog, while the AKARI catalog provides the data at 11 and $15{\mu}m$, covering the near- to mid-infrared spectral range continuously.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 추계학술대회논문집
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• pp.1009-1013
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• 2007

To do a HRTF customization, researchers used a spherical head model for modeling the head block of structural modeling of HRTF, which is the one of the technique for HRTF customization, because of its simplicity. In this paper, an analytic spheroidal HRTF caused by an incident point source will be introduced. Using proposed spheroidal HRTF, near-field HRTF customization can be applicable through a structural modeling of HRTF. To see the necessity of sheroidal head model, comparison of two analytic solutions, which are classical spherical HRTF and proposed spheroidal HRTF, will be shown. On the view point of ITD, optimal head model which matches with the measured ITD of KEMAR HRTF can be obtained. ITD results show that there are only slight differences between spherical and spheroidal head model. Magnitude comparison is made by constructing head model using measured head size. Although magnitude comparison is not studied between optimal models, the results of 24 of 36 subjects are shown that spheroidal head model matches notch frequency pattern of measured HRTF better than those of spherical one, where the sound source is at contralateral position.

• 한국물환경학회지
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• 제24권2호
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• pp.169-173
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• 2008

A field monitoring was conducted in order to find out the discharge characteristics of non-point source pollutants in the agricultural area. Event Mean Concentration (EMC) of TSS, $BOD_5$, $COD_{Mn}$, TP, TN was calculated based on the monitoring data of 10 rainfall events at agricultural watersheds. A significant relationship was observed from the correlation between EMCs and rainfall characteristics. The result shows that EMC ranges of 95% confidence intervals were 50.5~203 mg/L for TSS, 0.8~14.2 mg/L for $BOD_5$, 4.2~20.7 mg/L for $COD_{Mn}$, 2.4~4.5 mg/L for TN and 0.2~0.5 mg/L for TP, respectively. The correlation coefficients between TSS and TP and between $BOD_5$ and $COD_{Mn}$ were found to be 0.912 and 0.961. But TN was lower correlated with other EMC factors. It was also found that rainfall characteristics was not correlated with EMCs.