• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.774-779
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• 2007

IDF 곡선은 전통적으로 지점에서의 과거 관측 강우량 시계열 자료를 수집하여 작성하여 왔으며, 이때 과거 강우량 자료는 정상성을 지니고 있고 미래를 대변한다는 가정을 전제로 한다. 그러나 이미 많은 연구자들에 의해 기후변화가 전구적으로 발생하고 있으며 우리나라에서도 더 이상 기후변화의 사실여부는 이제 더이상 논란 꺼리가 아니다. 특히, 기후변화의 영향을 직접적으로 받을 수밖에 없는 수자원 분야에서는 1990년대부터 잦은 홍수와 가뭄의 반복으로 곤란을 겪고 있다. 특히, 우리나라는 협소한 국토면적과 과다한 인구로 토지나 수자원 등 국토자원 이용의 강도가 다른 나라에 비하여 현저하게 높기 때문에 지구온난화에 따른 기후변화와 같은 약간의 기후변동으로도 심각한 문제가 발생할 가능성이 내포되어 있다. 특히, 기후변화는 유역 규모의 강우 발생 패턴과 강우량의 증가 및 감소에 영향을 미치게 되며 이로 인해 강우 시계열 자료는 비정상성과 경향성을 지니게 된다. 그러나 지금까지는 IDF 곡선의 작성시 강우의 경향성을 무시해 왔다. 본 연구에서는 기후변화가 IDF 곡선에 미치는 영향을 분석하기 위하여 GCM 기후변화 시나리오를 이용하여 IDF 곡선을 작성하였다. 이를 위하여 먼저, YONU CGCM의 제한실험과 점증실험을 실시하여 전구적 규모의 기후변화 시나리오를 작성하였으며, 통계학적 축소기법과 추계학적 일기발생기법을 이용하여 대상지점의 일 수문기상 시계열을 모의하였다. 그리고 BLRP(Bartlett Lewis Rectangular Pulse) 모형과 분해(koutsoyiannis, 2000) 기법을 이용하여 모의된 일 강우 자료를 시자료로 분해하였으며 이를 이용하여 IDF 곡선을 작성하였다. 그 결과, 기후변화 시 지속기간별 재현기간별 강우량이 현재에 크게 비해 증가됨을 확인할 수 있었다.으며 여러명이 동시에 서버에 접속을 하기 때문에 컴퓨터에 부하가 많이 걸리는 모델링이나 복잡한 분석은 실시하기 어려우며, 대용량 데이터를 전송할 수 있는 대역폭이 확보 되어야 한다. 또한, Internet 환경으로 개발을 해야되기 때문에 데스크탑용 GIS에 비해 개발속도가 느리며 개발 초기비용이 많이 들게 된다. 하지만, 네트워크 기술의 발달과 모바일과의 연계 등으로 이러한 약점을 극복할 수 있을 것으로 판단된다. 따라서 본 논문에서는 인터넷 GIS를 이용하여 홍수재해 정보를 검색, 처리, 분석, 예경보할 수 있는 홍수방재정보 시스템을 구축토록 하였다.비해 초음파 감시하 치골상부 방광천자가 정확하고 안전한 채뇨법으로 권장되어야 한다고 생각한다.應裝置) 및 운용(運用)에 별다른 어려움이 없고, 내열성(耐熱性)이 강(强)하므로 쉬운 조건하(條件下)에서 경제적(經濟的)으로 공업적(工業的) 이용(利用)에 유리(有利)하다고 판단(判斷)되어진다.reatinine은 함량이 적었다. 관능검사결과(官能檢査結果) 자가소화(自家消化)시킨 크릴간장은 효소(酵素)처리한 것이나 재래식 콩간장에 비하여 품질 면에서 손색이 없고 저장성(貯藏性)이 좋은 크릴간장을 제조(製造)할 수 있다는 결론을 얻었다.이 있음을 확인할 수 있었다.에 착안하여 침전시 슬러지층과 상등액의 온도차를 측정하여 대사열량의 발생량을 측정하고 슬러지의 활성을 측정할 수 있는 방법을 개발하였다.enin과 Rhaponticin의 작용(作用)에 의(依)한 것이며, 이는 한의학(韓醫學) 방제(方劑) 원리(原理)인 군신좌사(君臣佐使) 이론(理論)에서 군약(君藥)이 주증(主症)에 주(主)로 작용(作用)하는 약물(藥物)이라는 것을 밝혀주는 것이라고 사료(思料)된다.일전 $13.447\;{\mu}g/hr/g$, 섭취 7일중 $8.123

• Korean Journal of Environmental Agriculture
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• v.1 no.1
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• pp.59-64
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• 1982

Studies on the effect of soil moisture, different seasons, harvesting periods and nitrogen application on the nitrate content of radish(Raphanus sativus L. var. niger(Mill.) S. Kerner) were carried out in pot and green house. The results are as follows; The low level of soil moisture leads to an increased nitrate accumulation in radish root. The nitrate content was found to be higher in spring crops and lower in summer ones. It was decreased during harvesting period. The application of nitrogen fertilizer increased the nitrate content in radish root. We found the highest content in petioles with lesser content in roots and leaf blades in that order. The multiple regression analysis and the nutritional value of nitrate content in radish were discussed.

• Korean Journal of Social Welfare
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• v.38
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• pp.153-179
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• 1999

Despite the enforcement of minimum legal drinking age of 18 years of age since 1997, alcohol experimentation among Korean youth is believed to be greater than ever before. The use of alcohol jeopardizes physical, mental, and social development during a person's formative years, thereby endangering successful transitions from adolescent to adulthood. Even infrequent use of alcohol may result in intoxication and acute consequences, especially among youth, who may have low tolerance due to their smaller body size and may lack experience with the effects of alcohol. Using self-report questionnaire data collected from 1,697 highschool students nation-wide, the drinking behavior among Korean high school students and the relation between adolescents' alcohol expectancy and adolescent alcohol use patterns were examined. Results indicated that gender and the type of school(academic or vocational) were significant effects on the drinking behavior(drinking frequency, experience of drunkenness, the amount of alcohol consumed, experience of binge drinking and that of problems due to drinking). Male students than female students, and students of vocational schools rather than those of academic high schools reported more alcohol experimentation. Also, positive alcohol expectancy proved to have a significant relation with alcohol use among high-school students. That is, students who reported to think alcohol would have a positive effect on socializing, aggressiveness, relaxation of tensions, and enforcing sexual ability tended to drink more, to experience more binge drinking and more drinking problems. Variables of gender and the type of school also were found to have significant effects on alcohol expectancy. Males and students of vocational school held ideas of positive outcomes on drinking than others. Implications for further study on developing prevention programs are presented.

• Journal of Korea Water Resources Association
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• v.41 no.3
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• pp.341-351
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• 2008

Since the damage from the torrential rain increases recently due to climate change and global warming, the significance of flood forecasting and warning becomes important in medium and small streams as well as large river. Through the preprocess and main processes for estimating runoff, diverse errors occur and are accumulated, so that the outcome contains the errors in the existing flood forecasting and warning method. And estimating the parameters needed for runoff models requires a lot of data and the processes contain various uncertainty. In order to overcome the difficulties of the existing flood forecasting and warning system and the uncertainty problem, ANFIS(Adaptive Neuro-Fuzzy Inference System) technique has been presented in this study. ANFIS, a data driven model using the fuzzy inference theory with neural network, can forecast stream level only by using the precipitation and stream level data in catchment without using a lot of physical data that are necessary in existing physical model. Time series data for precipitation and stream level are used as input, and stream levels for t+1, t+2, and t+3 are forecasted with this model. The applicability and the appropriateness of the model is examined by actual rainfall and stream level data from 2003 to 2005 in the Tancheon catchment area. The results of applying ANFIS to the Tancheon catchment area for the actual data show that the stream level can be simulated without large error.

• The Korean Journal of Applied Statistics
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• v.26 no.2
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• pp.335-347
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• 2013

There are various types of real world signals. For example, an electrocardiogram(ECG) represents myocardium activities (contraction and relaxation) according to the beating of the heart. ECG can be expressed as the fluctuation of ampere ratings over time. A signal is a composite of various types of signals. An orchestra (which boasts a beautiful melody) consists of a variety of instruments with a unique frequency; subsequently, each sound is combined to form a perfect harmony. Various research on how to to decompose mixed stationary signals have been conducted. In the case of non-stationary signals, there is a limitation to use methodologies for stationary signals. Huang et al. (1998) proposed empirical mode decomposition(EMD) to deal with non-stationarity. EMD provides a data-driven approach to decompose a signal into intrinsic mode functions according to local oscillation through the identification of local extrema. However, due to the repeating process in the construction of envelopes, EMD algorithm is not efficient and not robust to a noise, and its computational complexity tends to increase as the size of a signal grows. In this research, we propose a new method to extract a local oscillation embedded in a signal by utilizing the second derivative.

• Journal of Soil and Groundwater Environment
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• v.8 no.1
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• pp.75-80
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• 2003

Understanding the seawater infiltration into tidal flat sediments is very important, because it is significantly correlated with the supply of dissolved oxygen, nutrients and organic matter to benthic organisms for survival. However oil blocks interstitial spaces of sediments, reduces seawater infiltration and results in the decrease in oxygen, nutrients and other food supply to benthic communities. The penetration depth of the stranded oil into the sediments is one of the most significant information to know the effect of spilled oil on biological communities and to set up a cleaning method. So we initiated this study to quantify the penetration behavior of spilled oil and to evaluate the influence of the penetrated oil on seawater infiltration in tidal flat environment and its ecological implications. The penetration depth of the crude oil into the tidal flat sediments was two times deeper than that of the fuel oil C, and the depth was significantly affected by stranded oil volume. However, the penetration depth of stranded oil was abruptly dropped at first falling tide but not significantly fluctuated after that. Moreover, hydrocarbon concentration showed the highest within the upper 2 cm. Seawater infiltration was decreased in proportion to the stranded oil volume. The seawater infiltration was more affected by the penetrated fuel oil C about 1.7 times than the crude oil, because the interstitial spaces of the top of sediments were more cleared by the fuel oil C. Therefore, quick cleaning actions for penetrated oil will be necessary for recovery of seawater infiltration because the seawater contains oxygen and nutrients necessary for the survival of benthic organisms in tidal flat.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.38 no.6
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• pp.839-850
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• 2018

The flood damage in urban areas due to torrential rain is increasing with urbanization. For this reason, accurate and rapid flooding forecasting and expected inundation maps are needed. Predicting the extent of flooding for certain rainfalls is a very important issue in preparing flood in advance. Recently, government agencies are trying to provide expected inundation maps to the public. However, there is a lack of quantifying the extent of inundation caused by a particular rainfall scenario and the real-time prediction method for flood extent within a short time. Therefore the real-time prediction of flood extent is needed based on rainfall-runoff-inundation analysis. One/two dimensional model are continued to analyize drainage network, manhole overflow and inundation propagation by rainfall condition. By applying the various rainfall scenarios considering rainfall duration/distribution and return periods, the inundation volume and depth can be estimated and stored on a database. The Rainfall-Duration-Flooding Quantity (RDF) relationship curve based on the hydraulic analysis results and the Self-Organizing Map (SOM) that conducts unsupervised learning are applied to predict flooded area with particular rainfall condition. The validity of the proposed methodology was examined by comparing the results of the expected flood map with the 2-dimensional hydraulic model. Based on the result of the study, it is judged that this methodology will be useful to provide an unknown flood map according to medium-sized rainfall or frequency scenario. Furthermore, it will be used as a fundamental data for flood forecast by establishing the RDF curve which the relationship of rainfall-outflow-flood is considered and the database of expected inundation maps.

• International Area Studies Review
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• v.20 no.1
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• pp.105-125
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• 2016

The expansionary monetary policy was practiced after 2001 in Japan to treat the deflation spiral, and reduced only the nominal interest rates and domestic household demand. One of the most serious factors for this failure was the change of private sector's expectancy. This paper has studied the effect of Japanese monetary policy in 21c., with empirical research based on a renewed macroeconomic model and the VAR. The empirical analysis shows that the effect of monetary policy on the national income during 2001.01-2015.03 is weaker than that of 1985.01-1994.04. Money volume has a diminutive effect on the growth of GDP within a short term after 2001. The change in the expectations of the private sectors might have been the cause of ineffectiveness of the expansive monetary policy. Economic agents learned from the past Japanese financial crisis that an expansive monetary policy increased the inflation rate and caused the 'bubbles to burst' afterwards. The VAR analysis says that the effectiveness of monetary policy on the economic depression declined over the past 20 years and the expansion of money volume has no influence on exchange rate and net export. This means that the expansive monetary policy lost its effect on net export and national income steadily. Monetary policy makers have to recognize this fact, and to consider another anti-cycle political instrument, i.e. the fiscal policy with government debt.

• Journal of the Korea Institute of Information Security & Cryptology
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• v.20 no.2
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• pp.43-55
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• 2010

${\mu}TESLA$ broadcast authentication protocol have been developed by many researchers for providing authenticated broadcasting message between receiver and sender in sensor networks. Those cause authentication delay Tree-based ${\mu}TESLA$[3] solves the problem of authentication delay. But, it has new problems from Merkel hash tree certificate structure. Such as an increase in quantity of data transmission and computation according to the number of sender or parameter of ${\mu}TESLA$ chain. ${\mu}TPCT$-based ${\mu}TESLA$[4] has an advantages, such as a fixed computation cost by altered Low-level Merkel has tree to hash chain. However, it only use the sequential values of Hash chain to authenticate ${\mu}TESLA$ parameters. So, It can't ensure the success of authentication in lossy sensor network. This paper is to propose the improved method for Tree-based ${\mu}TESLA$ by using XOR-based chain. The proposed scheme provide advantages such as a fixed computation cost with ${\mu}$TPCT-based ${\mu}TESLA$ and a message loss-tolerant with Tree-based ${\mu}TESLA$.

• The Korean Journal of Air & Space Law and Policy
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• v.33 no.1
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• pp.3-43
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• 2018

Auf die ganze Welt macht unbemannte $Flugger{\ddot{a}}te$(sog.Drohnen) in vielen Bereichen rasch Fortschritte und Anwendungen gezeigt. Nachdem ferngesteuerte Drohnen $urspr{\ddot{u}}nglich$ $prim{\ddot{a}}r$ $f{\ddot{u}}r$ $milit{\ddot{a}}rische$ Zwecke entwickelt wurden, $erh{\ddot{o}}cht$ sich derzeit ihre zivile Nutzung sowohl im Freizeit- als auch im Dienstleistungsbereich(Paketdrohnen, Drohnen-taxi) stetig. Mit der vermehrten Drohnennutzung steigen allerdings auch die damit verbundenen Risiken und Herausforderungen. In Zusammenhang damit stellt sich dann die Frage, ob $gegenw{\ddot{a}}rtige$ Vorschriften im Bereich von Luftrecht zurecht gekommen sind. Es sieht sich gerade der zwei Schwerpunkt $gegen{\ddot{u}}ber$. Erstens kann $Passagierebef{\ddot{o}}rderung$ mit unbemanntem Luftfahrzeug(mehr als 150kg) im $gegenw{\ddot{a}}ritigen$ Luftrecht keine Anwendung finden. Denn das kor. Luftsicherheitsgesetz und sein Durchsetzungsverordnung definieren die Terminologie von unbemannten Luftfahrzeugen und unbemannten $Flugger{\ddot{a}}te$ als "wenn eine Person nicht an Bord geht und ferngesteuert wird". Also soll Drohne nach dieser gesetzlichen Definition nur "ohne Person" geflogen werden. Das besagt ohne Piloten und ohne Passagiere. Zweitens ist unbemannte $Flugger{\ddot{a}}te$(weniger als 150kg) nicht auf Handelsgesetz anzuwenden, auf das ${\ddot{u}}ber$ Anspruchsgrundlage und Zurechnungsnorm des gewerblichen Luftverkehr geregelt ist. Der unbemannte Luftfahrzeuglieferdienst bringt nicht nur die Gefahr einer $Besch{\ddot{a}}digung$ des Frachtguts mit sich, sondern auch die Gefahr von $Bodensch{\ddot{a}}den$ durch Dritte. Gemäß ${\S}$ 896 des Handelsgesetzes ist aber die Anwendung von unbemannte $Flugger{\ddot{a}}te$(weniger als 150kg) $hierf{\ddot{u}}r$ begrenzt, weil unbemannt $Flugger{\ddot{a}}te$ $einschl{\ddot{a}}gig$ in Ultralight $Flugger{\ddot{a}}t$ ist, die im Handelsgesetz ausschließlich besteht. Technische Fortschritt und die dadurch $erm{\ddot{o}}glichten$ kommerziellen Anwendungen werden die Nachfrage nach unbemannter $Flugger{\ddot{a}}te$ wecken. Die Umsetzung der $bez{\ddot{u}}glichen$ Vorschriften sollte auch diese Entwicklung aktiv begleitet und $fr{\ddot{u}}hzeitig$ kommuniziert und erarbeitet werden, damit Hersteller und Nutzer $fr{\ddot{u}}hzeitig$ Planungssicherheit haben.