• Journal of Korea Water Resources Association
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• v.47 no.5
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• pp.421-433
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• 2014

In this study, monthly and annual aridity indices which are the ratios of precipitation to potential evapotranspiration in Seoul climate measurement station were analyzed for past 50 years (1961~2010), and the ratio of aridity index simulated by climate change scenarios (RCP 4.5 and 8.5) for each future period (2011~2040, 2041~2070, 2071~2100) to aridity index for the past period (1971~2000) was analyzed. Furthermore, 5 different potential evapotranspiration equations (FAO P-M, Penman, Makkink, Priestley-Taylor, Hargreaves) were applied to analyze the effect of potential evapotranspiration equation on estimating aridity index and aridity index variation ratio (%). The study results indicate that the monthly precipitation, average temperature and potential evapotranspiration were increased in each future period as compared to past period for both RCP 4.5 and RCP 8.5. Furthermore, winter period showed more significant increase of potential evapotranspiration than summer period, but aridity index showed different patterns as compared with potential evapotranspiration reflecting the influence of precipitation. Therefore, it is necessary to make preparation for the increment of winter evapotranspiration in terms of water resources management. The monthly and annual aridity indices based on future climate change scenarios were greatly different according to potential evapotranspiration equations; however, monthly and annual patterns of aridity index variation ratio (%) in the future period as compared to past period were very similar regardless of applied potential evapotranspiration equation.

• Journal of the Korean Geographical Society
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• v.42 no.6
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• pp.835-850
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• 2007

This study examines long-term trends of onset dates and durations of season decomposed by applying a lowpass filtering using observed 80-year(1921-2000) data and projected 2040s and 2090s data based on the IPCC SRES A1B emission scenario in South Korea. As recent climate changes on seasonal cycles in South Korea, the onset dates of spring and summer began earlier after 1970s. But onset dates of autumn and winter were delayed. Winter duration was more shortened during the post-1990 period. Summer duration is longer and winter duration is shorter at southern and eastern coastal area. The different of summer duration and winter duration in coastal area was longer than over the inland. The reduction in winter duration in South Korea agrees with results in overall global warming trends as a climate change signal. Future model output data predict that winter will disappear in Gangneung, Busan and Mokpo in the 2090s

• Proceedings of the Korea Water Resources Association Conference
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• 2016.05a
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• pp.211-211
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• 2016

도시 배수 시스템의 설계 및 홍수 방지 전략의 수립은 공통적으로 특정 재현 기간에 대한 극한강우량의 정보가 필요하다. 최근 이상기후로 인한 극한강우사상의 발생이 잦아짐에 따라, 수공 구조물의 설계 및 계획에 기후변화의 영향(특히 강수량)이 고려되어야 한다. 이에 본 연구에서는 설계에 사용되는 일반적인 재현기간의 IDF(intensity duration frequency)곡선에서 극한강우량을 산출하고, 이를 분석한 통계학적인 추세가 기후변화 시나리오의 IDF곡선의 작성에 미치는 영향에 대한 평가를 실시하였다. 연구 첫 단계에는 연 최대 일강수량 시계열의 추세를 분석하고 정량화하였다. 본 연구에서는 1970년부터 2015년까지의 60개 관측소의 연 최대 일강수량 시계열을 사용하여 분석하였으며, 관측소별로 다른 유의수준을 고려하여 Mann-Kendall test가 실시되었다. 그 결과 연구기간동안 증가 및 감소 추세가 발생하였다. 추세가 분석 및 정량화 되면, Gumbel 분포를 이용하여 극한강우량을 계산하였다. 마지막으로 지역별로 실시한 추세분석으로부터 얻은 정보를 통합하고 추세분석 결과를 바탕으로 2가지의 기후 시나리오를 규정하여 IDF곡선의 매개변수를 산정하였다. 그 결과, 통계학적인 추세의 증가 또는 감소 모두 각 지속시간의 극한강우시계열에 영향을 주는 것으로 나타났다.

• Food Industry And Nutrition
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• v.8 no.3
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• pp.9-17
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• 2003

숙성 기간(1, 3 및 5년)이 다른 멸치 액젓으로부터 추출한 biocompound는 정제과정에서 숙성 1년의 멸치 액젓은 3개, 숙성 3년의 멸치 액젓은 4개, 숙성 5년의 멸치 액젓은 5개의 Peak를 각각 나타내었다. 숙성 기간이 길수록 멸치 액젓의 biocompound는 저분자화 었으며, gel chromatography상의 후반부에 나타났다. 숙성 기간이 다른 멸치 액젓으로부터 추출한 biocompound들의 생리활성(항산화, 항암, ACE 저해활성 )은 숙성 기간이 길수록 증가하였다 특히 항산화 및 항암활성은 $IC_{50}$/이 각각 34 및 44 $\mu\textrm{g}$/mL인 3년 숙성 peak 3이 제일 높았으나, ACE 저해 활성은 $IC_{50}$/이 32$\mu\textrm{g}$/mL인 1년 숙성 peak 3이 제일 높았다. 천연 숙성 멸치 액젓의 저분자 peptide는 뛰어난 생리활성을 갖고 있음이 밝혀졌으나 구조 분석 등의 추가 연구가 필요하다고 본다. 5년 숙성 멸치 액젓 분획 중 항산화활성이 높은 1-A-II-d와 1-A-III을 sequence analyzer로 분석한 결과 각각 glutamic acid및 lysine의 단일 아미노산으로 나타났다.

• Proceedings of the Korean Society of Computer Information Conference
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• 2020.07a
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• pp.457-458
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• 2020

신대영(2018, 2019)의 연구에서 RPG장르를 기준으로 T-test를 활용하여 두 게임간의 평균 이벤트 기간의 차이를 조사, 분석한 결과, 신대영(2018, 2019)의 두 연구 모두 두게임간의 평균 이벤트 기간은 차이가 없음을 알 수 있다. 이에 본 연구에서는 전체이용가, 12세이용가 그리고 청소년이용불가 게임을 선정하여 One-way ANOVA를 이용하여 세 게임간의 평균 차이를 연구하였다. 분산분석 결과, 유의수준 P값이 0.657(P>0.05)로 세 게임간의 이벤트 실시와 관련하여 평균의 차이가 없는 것으로 나타났다.

• Proceedings of the Korean Society of Disaster Information Conference
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• 2023.11a
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• pp.97-98
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• 2023

본 연구에서는 건설현장 관계자들을 대상으로 위험인식이 작업환경과 안전문화에 미치는 영향관계를 확인하였다. 또한, 안전관리활동과 공사기간이 안전문화에 미치는 영향을 분석하였다. 주요 결과는 다음과 같다. 첫째, 위험인식은 작업환경에 영향을 미치는 것으로 나타났으며, 둘째, 작업환경은 안전문화에 영향을 미치지 않았다. 셋째, 안전관리 활동은 안전문화에 영향을 미치지 않았으며, 넷째, 공사기간은 안전문화에 영향을 미치는 것으로 분석되었다. 또한, 안전관리 활동과 위험인식 간의 상관관계는 r=.61로, 위험인식과 공사기간은 r=.71로 안전관리 활동과 공사기간의 상관관계는 r=.59로 관계의 강도를 확인하였다.

• Water for future
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• v.27 no.3
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• pp.71-82
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• 1994

A statistical characteristics, relations of calendar and water year, and frequencies of precipitaion which are necessary for water resources planning were analyzed with long historical data(1905-1991 years). And the analysis of precipitation of the drought periods in 1967-1968 years was carried out. The study basins are the five major rivers in Korea. As a results of this study, annual precipitation shows an increasing trend but its variation has no statistical significance. The rellations of calendar and water year precipitation is presented, it shows that there are little difference of the total precipitation between them. The annual minimum series of total precipitation for the periods of 3, 6, 9, and 12 months by water year are constructed, and frequency precipitation for each periods using 2-parameter lognormal distribution is presented. The analysis of the precipitation in 1967-1968 years shows in a natural river basins that it would be a moderate drought, if dry seasons(Oct-May) or wet seasons(Jun-Sep) has 75 percents of historical mean precipitation of the same periods. And if it has less than 60 percents of historical mean precipitation, it would be a severe drought.

• Land and Housing Review
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• v.12 no.3
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• pp.27-37
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• 2021

This paper empirically examined the relationship between the housing market and the stock market to investigate the price and the asymmetric volatility spillover effects. The monthly housing price index and the monthly KOSPI were used for analysis. This research employed the EGARCH model. The analysis period was from January 1986 until June 2021 with periodization centered on the Asian Financial Crisis: before and after the crisis - the end of December 1997. The EGARCH model allows analysis of 'good news' and 'bad news' in understanding volatility. The price spillover effect was observed one way from the stock market to the housing market. On the contrary, the spillover effect was not found from the housing market to the stock market. The empirical evidence suggests that there are price and asymmetric volatility effects in the entire period of analysis in both housing and the stock markets. In the housing market, the negative effects of information were found pre-financial crisis while the positive effects, in other periods. However, in the stock market, the negative effects of information were found in the pre- and post-financial crisis periods. This means that the housing market is more affected by 'good news' than 'bad news' when information spreads to the markets while the stock market is more affected by 'bad news' than 'good news'. It is of significance to discover the variable returns by different information.

• Journal of the Korea Convergence Society
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• v.9 no.11
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• pp.353-361
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• 2018

The purpose of this study is to analyze how Corporate Real Estate Ratio affects Firm's Value for KOSPI Companies and KOSDAQ Companies. The period of analysis is the period of the Financial Crisis (2007-2008), the period immediately after the Financial Crisis (2009-2011), and the period following the introduction of IFRS (2012-2016). The samples of 2761 KOSPI Companies years and 3719 KOSDAQ Companies years are used in this study. The result of Regression Analysis shows that the higher Corporate Real Estate Ratio is, the more negative Firm's Value is. In the comparison of markets, both KOSPI Companies and KOSDAQ Companies had no statistically significant effects during the Financial Crisis. Although KOSDAQ Companies had a greater negative effect on the Firm's Value than KOSPI Companies right after the Financial Crisis, KOSPI Companies have had a greater negative influence on the Firm's Value than KOSDAQ Companies since the introduction of IFRS. Therefore, each corporation should pay more attention to identifying the appropriate amount of their Corporate Real Estate Ratio and should continue to analyze and make decisions on the most efficient use of real estate which is owned by each company. This study shows speciality in dividing into three period, such as the period of the Financial Crisis, the period immediately after the Financial Crisis, and the period following the introduction of IFRS and comparing the degree of influence on the KOSPI Companies and KOSDAQ Companies for the each period. I hope to study the factors that affect the company's real estate policy.

• The korean journal of orthodontics
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• v.26 no.3
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• pp.267-279
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• 1996

This study was investigated the changes during treatment and retention period in the Class III malocclusion patients and explored the correlationship between factors that showed relapse tendencies and pre-treatment skeletal pattern and the changes during treatment period. Numbers of total sample were 24 and their Hellman's dental age at the start of treatment was over III B and were retained at least over 1 year 6 months. The following conclusion were obtained by comparing the differences between treatment period and retention period, and after analysing the correlationship of factors that manifested relapse tendencies. 1. The angles formed by FH plane and occlusal plane, FH plane and mandibular plane, and mandibular incisor and mandibular plane changes showed rebound effect during retention period and among them occlusal plane angle and IMPA show reverse correlationship. 2. Upward displacement of the occlusal plane at the end of treatment has returning tendency, is proportional to the displacement during treatment period, but the angle between maxillary and mandibular 1st molar to its basal bone have been constantlsy maintained during the retention period. 3. Mandibular plane decrease during retention period and downward backward rotation during treatment period show correlationship.