• 사상체질의학회지
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• 제23권2호
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• pp.230-239
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• 2011

1. Objectives: The purpose of this study was to find out the distributional characteristics of dyspepsia according to Sasang Constitution. 2. Methods: The medical records of 108 subjects who have received prescriptions and diagnosis of Sasang constitution from June 2007 to April 2009 at a Korean Medical clinic in Seoul were reviewed. General factors and the frequency of the prescriptions according to Sasang constitution are compared and analyzed. 3. Results: Among the 108 subjects, 57(52.78%) persons were Soyangin, 27(25.00%) Taeumin, and 24(22.22%) Soeumin. The frequencies of the prescriptions of interior and exterior disease were compared. Exterior disease(89.47%) was higher than interior disease in Soyangin and interior disease was higher than exterior disease in Taeumin(88.89%) and Soeumin(91.67%). (p-value<0.001) The most common disease was Mangeum-syndrome(73.68%) of exterior disease in Soyangin, Dry-febrile symptom(88.89%) of interior disease in Taeumin and Taeum-syndrome(66.66%) of interior disease in Soeumin. 4. Conclusion: There were significant differences on the distribution of dyspepsia in interior or exterior disease according to Sasang Constitution.

• 한국환경과학회지
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• 제19권4호
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• pp.415-425
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• 2010

The purpose of the present study was to analyze the vegetation structure and distributional characteristics of Abies koreana forests in Mt. Halla, and to provide basicdata for an ecological study on Abies koreana in Mt. Halla. The results of the analysis showed that the mean importance percentage(M.I.P,) of Abies koreana in the Youngsil and Bangaeoreum and the Azalea field were 28.3%, 23.6%, and 46.4%, respectively. The ratios of DBH (diameter at breast height) to height were similar in all region, except in the Azalea field, where Abies koreana of various ages, both young and old, were found. The species diversity (H) of the upper and lower layers in the Youngsil and Bangaeoreum and in the Azalea field were 0.625 and 0.810, 0.731 and 0.848, and 0.342 and 0.757, respectively. A total of 52 community were distributed at locations higher than 1,300m above sea level. The proportions of each community in the whole Abies koreana forest were 56.5%(Azalea field), 11.0% (Youngsil trail at 1,550-1,650 m above sea level), and 8.1%(Janggumok and Kundurewat region). The total area of the Abies koreana forest was calculated to be 795.3ha by combining all the areas of each community. An Abies koreana forest with the largest area was found at locations 1,500-1,600 m above sea level, taking up 38.8% of the total Abies koreana forest area. For the slopes of the distributional area of Abies koreana, 46.1%(highest proportion) of the total area was $10\sim25^{\circ}$, and for the azimuth of the distributional area, 17.4%(the highest proportion) of the total area was $0-45^{\circ}$. The vegetation structure showed large differences between areas. It was found, however, that the distribution was mostly in the areas with a relatively gentle slope. It is suggested that research be done to forecast the possible changes in the differences in the vegetation structures between different areas caused by climate changes. In addition, there is a need to monitor the Abies koreana and alpine plants in the subalpine zones of Mt. Halla, which are sensitive to climate change, to obtain the basic data that are necessary for the protection and maintenance of the ecosystem.

• 한국지역지리학회지
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• 제3권1호
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• pp.81-98
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• 1997

본 연구는 최근 사회적 여건의 급격한 변화에 따라 제기되고 있는 노인문제, 장애자문제와 가정 해체에 의한 아동 및 청소년비행과 범죄문제, 여성의 높은 취업율에 의한 육아보육 및 부녀복지문제 등 삶의 질과 관련되는 광범위한 복지문제중 복지의 범위를 한정하여 대구의 복지시설현황과 분포특성을 고찰하여 지역사회의 복지시설 입지선정에 보탬이 되고자 하였다. 먼저 우리나라의 복지제도와 복지정책을 개관하고 대구의 사회복지시설현황을 이용시설과 수용시설로 대별하여 고찰하였다. 그리고 이러한 각 시설들의 분포특성을 규명하기 위해 각 동별로 생활보호대상자수, 60세 이상의 노인인구 및 노인인구비율, 6세 이하 아동인구 및 인구비율을 파악하여 각 시설들의 분포와의 관계를 설명하고 지도화하였다. 그 결과 각 시설들의 분포는 그 시설을 주로 이용하는 연령충의 분포 및 저소득층의 분포와 밀접한 관계를 가지고 있음을 확인하였다. 이는 우리의 사회복지시설이 아직도 보편적인 시설이 아니라 소외계층에 제한된 시설임이 입증되었으며 앞으로는 좀 더 보편적인 시설로의 운영 및 전향을 제언하며 시설의 불균등분포의 문제와 아울러 노후화와 염세성도 문제점으로 지적하고 싶다.

• 인지과학
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• 제23권3호
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• pp.295-322
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• 2012

본 연구에서는 벡터 공간 모델과 HAL (Hyperspace Analog to Language)을 적용해서 단어 의미 유사성을 군집한다. 일정한 크기의 문맥을 통해서 단어 간의 상관성을 측정하는 HAL을 도입하고(Lund and Burgess 1996), 상관성 측정에서 고빈도와 저빈도에 다르게 측정되는 왜곡을 줄이기 위해서 벡터 공간 모델을 적용해서 단어 쌍의 코사인 유사도를 측정하였다(Salton et al. 1975, Widdows 2004). HAL과 벡터 공간 모델로 만들어지는 공간은 다차원이므로, 차원을 축소하기 위해서 PCA (Principal Component Analysis)와 SVD (Singular Value Decomposition)를 적용하였다. 유사성 군집을 위해서 비감독 방식과 감독 방식을 적용하였는데, 비감독 방식에는 클러스터링을 감독 방식에는 SVM (Support Vector Machine), 나이브 베이즈 구분자(Naive Bayes Classifier), 최대 엔트로피(Maximum Entropy) 방식을 적용하였다. 이 연구는 언어학적 측면에서 Harris (1954), Firth (1957)의 분포 가설(Distributional Hypothesis)을 활용한 의미 유사도를 측정하였으며, 심리언어학적 측면에서 의미 기억을 설명하기 위한 모델로 벡터 공간 모델과 HAL을 결합하였으며, 전산적 언어 처리 관점에서 기계학습 방식 중 감독 기반과 비감독 기반을 적용하였다.

• 대한수학회보
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• 제55권3호
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• pp.679-698
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• 2018

In this paper, with optimal normalized constants, the asymptotic expansions of the distribution and density of the normalized maxima from generalized Maxwell distribution are derived. For the distributional expansion, it shows that the convergence rate of the normalized maxima to the Gumbel extreme value distribution is proportional to 1/ log n. For the density expansion, on the one hand, the main result is applied to establish the convergence rate of the density of extreme to its limit. On the other hand, the main result is applied to obtain the asymptotic expansion of the moment of maximum.

• 한국경영과학회지
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• 제28권4호
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• pp.145-153
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• 2003

In this Paper, we examine the limiting distributional behaviour of extreme values of mixed Erlang random variables. We show that, in the finite mixture of Erlang distributions, the component distribution with an asymptotically dominant tail has a critical effect on the asymptotic extreme behavior of the mixture distribution and it converges to the Gumbel extreme-value distribution. Normalizing constants are also established. We apply this result to characterize the asymptotic distribution of maxima of sojourn times in M/M/s queuing system. We also show that Erlang mixtures with continuous mixing may converge to the Gumbel or Type II extreme-value distribution depending on their mixing distributions, considering two special cases of uniform mixing and exponential mixing.

• 한국환경과학회지
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• 제9권2호
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• pp.137-144
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• 2000

The observations on the seasonal fluctuation and distributional characteristic of organic matters on surface sediments and its origin were carried out at the 25 stations in Keogeum-sudo, southern coast of Korean Peninsula from February to October in 1993. I made an analysis on the environmental factors for surface sediments such as temperature, ignition loss, chemical oxygen demand, pheopigment, total sulphide, water content, mud content in grain size, COD/IL ratio and COD/sulphide ratio. The results are as follows ; 1) The range of temperature on the surface sediments was between 6.2${\circ}C$ and 24.6${\circ}C$. The highest mean temperatuer of mud was 24.0${\circ}C$ in summer, the lowest 6.6${\circ}C$ in winter. 2) Ignition loss(IL) fluctuated between 1.2% in winter and 16.8% in spring, that is to say, the seasons of increasing in temperature were very high ignition loss. 3) Chemical oxygen demand(COD) showed the highest mean value of 20.52 mg/g dry in summer within the range of 15/46~32.78 mg/g dry, while showed the lowest of 5.79 mg/g dry in winter within the range of 7.4~17.39 mg/g dry. 4) Pheopigment concentrations showed the highest mean value of 4.85 $\mu\textrm{g}$/g dry in autumn within the range of 0.84~9.21 $\mu\textrm{g}$/g dry, while it did the lowest mean value of 1.97 $\mu\textrm{g}$/g dry in summer within the range of 0.23~4.83 $\mu\textrm{g}$/g dry. 5) Total sulphide (H2S) fluctuated between no detect(ND) in spring, and 2.43 mg/g dry in sutumn. The highest mean value was 0.68 mg/g dry in sutumn, the lowest was 0.16 mg/g dry in spring. 6) Water content(WC) and mud content in grain size showed the mean value of 43.2% within the range of 26.5~59.7% and 91.0% within the range of 57.8~99.2%, respectively. 7) By the analytical results on the source of organic matter, it had been dumped from the seaweed farms in Keogeum-sudo coastal waters.

• The Korean Journal of Ecology
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• 제5권4호
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• pp.143-153
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• 1982

Distributional pattern of vascular plant species in terms of species-area relationship and distances from their species pool on the 53 islands selected in the South Korea were studied. From the relationship between vascular plant species and area the equation of species-area was established as the follow: S=cA2 c=135.52 z=0.226 S; number of species A; area of island In the equation the Z value 0.226 is lower than those of any other localities reported in the world. Z value increased with the increasing distance from the species pool while C value decreased. The relationships of Z and/or C and distance from species pool, D, were established; Z=0.002D+0.176 C=-39.5logD+178.5 The tendency of common species decrease of them with the increasing islands was fifted to the Fisher's logarithm series. Common species 50% above was 39 species, including the most common species, Pinus thunbergii. Quotient of Similarity value by Sorensen (1948) on common species was relatively low i.e. 0.27∼0.47. It is noticeable for their vegetation conditions that the naturalized plant as a indicator of disturbance, for example Erigeron canadensis, was widely distributed.

• 통상정보연구
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• 제9권2호
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• pp.65-86
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• 2007

This paper reviews the properties and application methods of widely used types of risk measures, identifies the rationale and business-side effects of hedging, derives the theoretical formula of optimal hedging ratio, and analyzes the various functional aspects of VaR(Value-at-risk) as a risk measure and a hedging tool. Especially this paper focuses on the characteristics of VaR compared with other risk measures in terms of their own principal determinants and identifies its stronger aspects in the dimension of hedging strategy tools. As well, this paper provides the detailed processes deriving the optimal hedge ratios based on the distributional parameters and risk factors. In addition, this paper presents the detailed and substantial processes of estimating the minimum variance hedge ratio and minimum-VaR hedge ratio using the actual data and shows that the minimum variance hedge ratio proves helpful for many cases although it is not appropriate for the non-linear portfolio including the option contracts. We demonstrate the trade-off relationship between the minimum variance hedge strategy and the minimum-VaR hedge strategy in their hedging costs and performances through calculation of the respective VaRs and variances of unhedged and hedged portfolios and the optimal hedge ratio and hedging effectiveness values for the given long position in US Dollar with the short position in Euro.

• 재무관리연구
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• 제24권3호
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• pp.153-186
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• 2007

It is well known that the distributional properties of financial asset returns exhibit fatter-tails and skewer-mean than the assumption of normal distribution. The correct assumption of return distribution might improve the estimated performance of the Value-at-Risk(VaR) models in financial markets. In this paper, we estimate and compare the VaR performance using the RiskMetrics, GARCH and FIGARCH models based on the normal and skewed-Student-t distributions in two daily returns of the Korean Composite Stock Index(KOSPI) and Korean Won-US Dollar(KRW-USD) exchange rate. We also perform the expected shortfall to assess the size of expected loss in terms of the estimation of the empirical failure rate. From the results of empirical VaR analysis, it is found that the presence of long memory in the volatility of sample returns is not an important in estimating an accurate VaR performance. However, it is more important to consider a model with skewed-Student-t distribution innovation in determining better VaR. In short, the appropriate assumption of return distribution provides more accurate VaR models for the portfolio managers and investors.