• 한국관개배수논문집
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• 제21권1호
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• pp.89-98
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• 2014

This study is to evaluate the future potential impact of climate change on soil erosion loss in a metropolitan area using Revised Universal Soil Loss Equation(RUSLE) with land use information of the Ministry of Environment and rainfall data for present and future years(30-year period). The spatial distribution map of vulnerable areas to soil erosion was prepared to provide the basis information for soil conservation and long-term land use planning. For the future climate change scenario, the MIROC3.2 HiRes A1B($CO_2720ppm$ level 2100) was downscaled for 2040-2069(2040s) and 2070-2099(2080s) using the stochastic weather generator(LARS-WG) with average rainfall data during past 30 years(1980-2010, baseline period). By applying the climate prediction to the RUSLE, the soil erosion loss was evaluated. From the results, the soil erosion loss showed a general tendency to increase with rainfall intensity. The soil loss increased up to 13.7%(55.7 ton/ha/yr) in the 2040s and 29.8%(63.6 ton/ha/yr) in the 2080s based on the baseline data(49.0 ton/ha/yr).

• 천문학회보
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• 제36권2호
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• pp.100.1-100.1
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• 2011

Everybody wants to see the future, but nobody does for sure. Reliably forecasting the solar activity in the near future looks like an easy task, but in fact still remains one of difficult problems in the solar-terrestrial research. We have sought for good univariate methods that can predict future smoothed sunspot numbers reasonably well based on past smoothed sunspot number data only. Here we consider a specific method we call principal component-and-autoregression (PCAR) method. The variation of sunspot number during a period of finite duration (past) before an epoch (present) is modeled by a linear combination of a small number of dominant principal components, and this model is extended to the period (future) beyond the epoch using the autoregressive model of finite order. From the application of this method, we find that the $24^{th}$ solar maximum is likely to occur near the end of the year 2013 (and there is a possibility that it occurs earlier near the start of 2013), and to have a peak sunspot number of about 86, indicating that the activity of the $24^{th}$ cycle will be weaker than the average. We will discuss how much this estimate is reliable.

• 한국지반공학회지:지반
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• 제13권6호
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• pp.5-12
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• 1997

연약지반 개량을 위한 프리로딩 공법에서 침하 애측은 시공관리상 매우 중요한 요소이다. 지반의 비균질성, 지반 물성치 조사의 한계 등의 이유로 설계시에 침하속도 및 침하량을 실제 발생치와 근접하게 예측하기는 매우 어렵다. 이러한 문제점 때문에 쌍곡선법,아사오카법 등 초기 침하계측을 이용한 장래 침하 추정 법들이 침하 예측 기법으로 활발하게 이용되고 있으나, 예측 시점에서 추정된 장래 침하량의 신뢰성에 대한 평가 방법엔 대하여서는 제시된 바가 없다. 본 연구는 사례연구를 통하여 쌍곡선법으로 예측된 장래침하량들과 실 침하량들을 비교하구 초기 계측 기간에 따른 장래 침하량 예측의 신뢰성에 관한 분석을 통하여. 쌍곡선법을 이용한 장래 침하량 추정의 신뢰성 평가 방법을 제시하고자 한다.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 정기총회 및 추계학술대회 논문집
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• pp.320-328
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• 2011

The down town passage segment which follows in the straight line which follows recently in high speed of the railway and rail construction is increasing. Also according to quality of life improvement of the citizens whom follows in national income increase the resident demand only becomes larger day by day about a environmental creation which is comfortable and house environmental etc. Demand of the citizens is not the problem of today yesterday about like this railway mean of transportation and with the fact that continuously will increase in future. This study is to predict and reduce railway noise from the conventional PSC-beam bridges which passes through urban areas under the government strateges of speed and weight increases of railway. The purpose of this study is to recommend a proper noise prediction method for designing pleasant roadside environments. The railway design including existing line reconstructions should minimize curved alignment to increase train speed to 180~200km/hr under the government's long-term planing such as the 4th Comprehensive National Development Plan (2000~2020), National Intermodal Transportation Plan (2000~2019) and National Railroad Network Establishment Plan (2006~2015), Since the PSC-beam bridges are mainly used for bridge structures urban areas, noise measurements were performed and analyzed to recommend the noise prediction methods for each type and speed of train respectively.

• Asian Journal of Atmospheric Environment
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• 제10권4호
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• pp.197-207
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• 2016

Large quantities of air pollutants are released into the atmosphere and hence, must be monitored and routinely assessed for their health implications. This paper proposes a stochastic technique to predict unobserved hazardous air pollutants (HAPs), especially Benzo[a]pyrene (BaP), which can have negative effects on human health. The proposed approach constructs a nearest-neighbor structure by incorporating the linkage between BaP and meteorology and meteorological effects. This approach is adopted in order to predict unobserved BaP concentrations based on observed (or forecasted) meteorological conditions, including temperature, precipitation, wind speed, and air quality. The effects of BaP on human health are examined by characterizing the cancer risk. The efficient prediction provides useful information relating to the optimal monitoring period and projections of future BaP concentrations for both industrial and residential areas within Korea.

• Earthquakes and Structures
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• 제15권1호
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• pp.29-44
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• 2018

A ground-motion prediction equation (GMPE) for the Korean Peninsula, especially for South Korea, is developed based on synthetic ground motions generated using a ground motion model derived from instrumental records from 11 recent earthquakes of $M_L$>4.5 in Korea, including the Gyeongju earthquake of Sept. 12. 2016 ($M_L$5.8). PSAs of one standard deviation from the developed GMPE with $M_W$ 6.5 at hypocentral distances of 15 km and 25 km are compared to the design spectrum (soil condition, $S_B$) of the Korean Building Code 2016 (KBC), indicating that: (1) PSAs at short periods around 0.2 sec can be 1.5 times larger than the corresponding KBC PSA, and (2) SD's at periods longer than 2 sec do not exceed 8 cm. Although this comparison of the design spectrum with those of the GMPE developed herein intends to identify the characteristics of the scenario earthquake in a lower-seismicity region such as South Korea, it does not mean that the current design spectrum should be modified accordingly. To develop a design spectrum compatible with the Korean Peninsula, more systematic research using probabilistic seismic hazard analysis is necessary in the future.

• 물과 미래
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• 제28권1호
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• pp.81-90
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• 1995

본 연구에서는 장기간의 수문기상자료를 보유하고 있으나 유출량자료의 관측년한이 짧은 유역에서 장기간의 월유출량자료를 확장하고 예측할 수 있는 추계학적 시스템 모형을 개발하고자 한다. 그 방법으로 주기성과 경향성을 갖는 월유출량, 월강수량 및 윌증발량자료를 시계열 분석하여 seasonal ARIMA 형태의 단변량 모형을 유도하는 한편, 각 계열간의 교차상관분석으로부터 월강수량 및 윌증발량을 입력변수로 하고 월유출량을 출력변수로 하는 다중 입력-단일 출력관계의 설명모형을 유도하여 단변량 시계열모형과 비교 검토하였다. 본 연구의 결과 월유출량자료의 확장과 예측에 있어서 다중 입출력모형의 정확성과 적용가능성이 매우 높은 것으로 판단되었다.

• ETRI Journal
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• 제30권2호
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• pp.227-237
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• 2008

In this paper, an algorithm that provides absolute and proportional differentiation of packet delays is proposed with the objective of enhancing quality of service in future packet networks. It features an adaptive scheme that adjusts the target delay for every time slot to compensate the deviation from the target delay, which is caused by prediction error on the traffic to arrive at the next time slot. It predicts the traffic to arrive at the beginning of a time slot and measures the actual arrived traffic at the end of the time slot. The difference between them is utilized by the delay control operation for the next time slot to offset it. Because the proposed algorithm compensates the prediction error continuously, it shows superior adaptability to bursty traffic and exponential traffic. Through simulations we demonstrate that the algorithm meets the quantitative delay bounds and is robust to traffic fluctuation in comparison with the conventional non-adaptive mechanism. The algorithm is implemented with VHDL on a Xilinx Spartan XC3S1500 FPGA, and the performance is verified under the test board based on the XPC860P CPU.

• 한국환경과학회지
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• 제18권6호
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• pp.683-690
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• 2009

The water quality of reservoir can be controled by water quality prediction model because it can not only grasping the present water state but also predicting the water quality in future. In this study, WASP model is used to predict the water quality of Chungju reguration reservoir. This model has some special option which predicts the pollutant outflow phenomenon caused by the contamination sources. So this model is widely used because that can present the scientific basis in this field. This model can help the managers make the right choice of water quality policy. Environmental grade of Chungju reguration reservoir is in III,IV grade which is in bad condition comparatively. The water contamination will be in poor as the year passes. When considering T-N, T-P which are the nutrient to control eutrophication, the concentrated administration about contamination sources is in urgent.

• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.32.1-32.1
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• 2008

It is well known that solar and space weather activities can influence the performance and reliability of modern technological system and can endanger human life. Since 2007, the Korea Astronomy and Space Science Institute (KASI) has initiated a research project for the construction of Korean Space Weather Prediction Center (K-SWPC) to make preparations for the next solar cycle maximum (~2012). In this talk, we briefly introduce the current progress of KASI activities for K-SWPC; extension of ground observation system, construction of space weather database and network, development of prediction models, and space weather effects. In addition, future plans for KSWPC will be discussed.