• 한국농공학회논문집
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• 제57권1호
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• pp.89-97
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• 2015

This study is to assess the effect of non-point source pollution discharge loads between tillage and no-tillage applications for upland crop areas using SWAT (Soil and Water Assessment Tool) watershed modeling. For Byulmi-cheon small rural catchment ($1.17km^2$) located in upstream of Gyeongan-cheon watershed, the rainfall, discharge and stream water quality have been monitored in the catchment outlet since 2011. The SWAT model was calibrated and validated in hourly basis using 19 rainfall events during 2011-2013. The average Nash-Sutcliffe model efficiency and $R^2$ (determination coefficient) for streamflow were 0.67 and 0.79 respectively. Using the 10 % surface runoff reduction from experiment results for no-tillage condition in field plots of 3 % and 8 % slopes under sesami cultivation, the soil saturated hydraulic conductivity for upland crop areas was adjusted from 0.001 mm/hr to 0.0025 mm/hr in average. Under the condition, the catchment sediment, T-N (total nitrogen, TN), and T-P (total phosphorus, TP) discharge loads were reduced by 6.9 %, 7.4 %, and 7.7 % respectively.

• 한국환경보건학회지
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• 제24권1호
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• pp.80-86
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• 1998

Seom River was major branch of Namhan river, consist of primary basin that Wonjoo-city, Hoingsung-gun and primary contamination source was sewage from human lives. This study was evaluated production contamination loading of each branch basin and water quality grade and water quality simulation by QUAL2E to provide efficient contaminations source control. Rusult of survey, production loading of BOD, T-N, T-P were 26,591 kg/day, 4,560 kg/day, 731 kg/day resectively. Water quality analysis in 17 points of main stream were appeared that 1st grade(BOD 1 mg/l under) was 6 point, 2nd grade was 9 point and 3rd grade was 2 point. And result of water quality analysis for branch steram, first grade was evaluated 68.7%. Based of field data, calibration and verification result were in good agreement with mesured value within coefficient of variance were from 2.59% to 18.73%, from 6.39%, to 28.46%, respectively.

• 대한전자공학회:학술대회논문집
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• 대한전자공학회 1998년도 추계종합학술대회 논문집
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• pp.1247-1250
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• 1998

In speech synthesis, LF model is widely used for excitation signal for voice source coding system. But LF model does not represent the harmonic frequencies of excitation signal. We propose an effective method which use sinusoidal functions for representing the harmonics of voice source signal. The proposed method could achieve more exact voice source waveform and better synthesized speech quality than LF model.

• 지구물리와물리탐사
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• 제21권1호
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• pp.1-7
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• 2018

전기탐사 2차원 모델링에서는 다수의 파수영역 전위를 계산하고 이를 푸리에 역변환하여 공간영역 전위를 계산한다. 푸리에 역변환은 여러 개의 서로 다른 파수에서의 파수영역 전위를 사용하여 수치적으로 얻어진다. 적분의 정확도를 향상시키기 위하여 파수의 크기에 따라 적분 구간을 지수 근사와 대수 근사 구간으로 분할하는 방법이 널리 사용되고 있다. 푸리에 역변환에는 크게 구간 적분법과 가우스 적분법이 사용되고 있다. 그러나 이들 방법은 송수신 간격을 고려하지 못하므로 송수신 간격에 따른 오차를 피할 수 없다. 특히 송수신 간격이 매우 작거나 클 경우 오차가 급격하게 증가하는 문제점을 가지고 있다. 이 연구에서는 송수신 간격을 고려하여 가우스 좌표값 및 가중값을 적용하는 새로운 수치 적분법을 개발하였다. 반무한 공간에 대한 수치 실험 결과, 개발된 수치 적분법은 송수신 간격에 관계없이 0.4% 이하의 정밀도를 나타내었다.

• 한국컴퓨터정보학회:학술대회논문집
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• 한국컴퓨터정보학회 2015년도 제51차 동계학술대회논문집 23권1호
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• pp.283-284
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• 2015

We can picture a workforce that extends beyond your employees: one that consists of any user connected to the Internet. Cloud, social, and collaboration technologies now allow organizations to tap into vast pools of resources across the world, many of whom are motivated to help. Channeling these efforts to drive business goals is a challenge, but the opportunity is enormous: it can give every business access to an immense, agile workforce that is not only better suited to solving some of the problems that organizations struggle with today but in many cases will do it for free. In this paper, we research on factors to design an organizational crowd source for Big Data.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2000년도 춘계학술대회논문집
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• pp.1704-1709
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• 2000

This paper proposes a spherical probe allowing acoustic intensity measurements in three dimensions to be made, which creates a diffracted field that is well-defined, thanks to analytic solution of diffraction phenomena. Six microphones are distributed on the surface of the sphere along three rectangular axes. Its measurement technique is not based on finite difference approximation, as is the case for the ID probe but on the analytic solution of diffraction phenomena. In fact, the success of sound source identification depends on the inverse models used to estimate inverse diffraction phenomena, which has non-linear properties. In this paper, we introduce the concept of nonlinear inverse diffraction modeling using a neural network and the idea of 3 dimensional sound source identification with several tests.

• Wind and Structures
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• 제3권1호
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• pp.11-21
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• 2000

This paper presents results of modeling of the passive contaminant diffusion from a continuous line finite-size source located on the underlying surface of a neutral near-ground atmospheric layer obtained by using the non-local two-parameteric turbulence model and the transport equation of mean concentration. In the proposed diffusion model the turbulent diffusion coefficient changes not only with the vertical coordinate but also with the distance downstream from the source according to the experimental data. The results of the modeling reproduce structural features of the concentration field.

• 지구물리와물리탐사
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• 제18권4호
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• pp.216-222
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• 2015

항공 전자 탐사법은 지하 천부의 전도성 광체 탐사를 위하여 이미 수십년 전에 도입되었다. 그러나 통상적인 시간 영역 항공 전자 탐사(ATEM) 시스템은 신호가 미약하여 가탐 심도에 한계가 있다. 최근 이러한 문제점을 극복하기 위하여 지상 송신원 시간 영역 항공 전자 탐사법(GREATEM)이 개발되었다. GREATEM은 지상에 설치된 긴 전선을 송신원으로 사용하는 준 항공 전자 탐사법이다. 항공 전자 탐사에서는 방대한 자료가 획득되므로, 계산 시간의 절감을 위하여 대개 1차원 해석 방법이 사용되고 있다. 그러나 GREATEM은 1차원 모델링의 경우에도 긴 전선을 따라 수치 적분이 필요하므로 루프 송신원을 사용하는 ATEM의 1차원 모델링에 비하여 계산 시간이 많이 걸린다는 문제점이 있다. 이 논문에서는 일반적인 1차원 모델링보다 비교할 수 없을 정도로 계산 속도가 빠른 ABFM법을 도입하여 ATEM 1차원 모델링을 수행하였다. 통상적인 모델링과 ABFM 결과를 비교한 결과, ABFM법은 GREATEM 1차원 모델링에도 적용 가능할 것으로 확인되었다.

• Journal of Electrical Engineering and Technology
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• 제13권5호
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• pp.2017-2032
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• 2018

This study presents, for the first time, state-of-the art review of the various techniques for the modeling of the electrostatic discharge (ESD) generators for the ESD analysis and testing. After a brief overview of the ESD generator, the study provides an in-depth review of ESD generator modeling (analytical, circuit and numerical modeling) techniques for the contact discharge mode. The proposed techniques for each modeling approach are compared to illustrates their differences and limitations.

• Nuclear Engineering and Technology
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• 제41권5호
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• pp.729-738
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• 2009

Given the evolution of High-Temperature Gas-cooled Reactor(HTGR) designs, the source terms for licensing must be developed. There are three potential source terms: fission products, actinides in the fuel and tritium in the coolant. It is necessary to provide first an inventory of the source terms under normal operations. An analysis of source terms has yet to be performed for HTGRs. The previous code, which can estimate the inventory of the source terms for LWRs, cannot be used for HTGRs because the general data of a typical neutron cross-section and flux has not been developed. Thus, this paper uses a combination of the MCNP, ORIGEN, and MONTETEBURNS codes for an estimation of the source terms. A method in which the HTR-10 core is constructed using the unit lattice of a body-centered cubic is developed for core modeling. Based on this modeling method by MCNP, the generation of fission products, actinides and tritium with an increase in the burnup ratio is simulated. The model developed by MCNP appears feasible through a comparison with models developed in previous studies. Continuous fuel management is divided into five periods for the feeding and discharging of fuel pebbles. This discrete fuel management scheme is employed using the MONTEBURNS code. Finally, the work is investigated for 22 isotope fission products of nuclides, 22 actinides in the core, and tritium in the coolant. The activities are mainly distributed within the range of $10^{15}{\sim}10^{17}$ Bq in the equilibrium core of HTR-10. The results appear to be highly probable, and they would be informative when the spent fuel of HTGRs is taken into account. The tritium inventory in the primary coolant is also taken into account without a helium purification system. This article can lay a foundation for future work on analyses of source terms as a platform for safety assessment in HTGRs.