• Korean Journal of Environment and Ecology
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• v.14 no.1
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• pp.67-79
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• 2000

지리산국립공원 동부지역의 해발고와 사면에 따른 식물군집구조를 파악하기 위하여 1999년 7월에 49개의 조사구(20m$\times$15m)를 설치하여 조사하였다 해발고가 올라감에 따라 북사면에 위치한 조사구에서는 구상나무와 신갈나무의 평균상대우점치가 증가하였고 천왕봉 해발 1,700m이상 지역에서는 가문비나무가 우점종이었으며 해발고가 올라갈수록 상대우점치는 증가하였다 반면 남사면에 위치한 조사구에서는 해발고가 올라감에 따라 신갈나무의 평균상대우점치는 감소하였고 구상나무의 평균상대우점치는 증가하였다 해발고에 따른 북사면과 남사면의 종수와 개체수는 북사면에서보다 남사면에서 많았고 입지환경과 종간상관관계에서는 가문비나무 신갈나무, 잣나무가 해발고와 정의 상관관계를 나타냈으며 서어나무는 부의 상관관계를 나타내었다 동일 해발고에서도 사면상 위치에 따라 식물군집구조 및 종구성의 차이를 나타내었다.

• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.9-24
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• 2009

We compare the relation among the annual distribution of sunspots: coronal mass ejections (CMEs) and geomagnetic storms and North-South asymmetry during solar cycle 23. For this purpose, we calculate correlation coefficients between (i) annual distribution and N-S asymmetry of CMEs - sunspots (ii) distribution of CMEs - occurrence number of geomagnetic storms (iii) distribution of sunspots - occurrence number of geomagnetic storms. We find that (i) the annual distribution of total CMEs has good correlation with distribution of annual average of sunspots but poor correlation with N-S asymmetry of sunspots, N-S asymmetry of CMEs has good correlation with N-S asymmetry of sunspots: (ii) total and N-S asymmetry of CMEs have poor correlation with occurrence number of geomagnetic storms, it's, however, well correlated with the classified groups of CMEs (Ap, Dst and an indices vs. fast CMEs($\upsilon$ > $1000kms^{-1}$), Dst index vs. Halo CMEs), and (iii) sunspot numbers and area are correlated with occurrence number of geomagnetic storms. We conclude that annual distribution of CMEs and sunspots have well correlated with geomagnetic storms, N-S asymmetry of CMEs and sunspots have poor correlated with the geomagnetic storms.

• Korean Journal of Environment and Ecology
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• v.13 no.4
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• pp.309-315
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• 2000

지리산국립공원 동부지역의 등산로 주연부식생 구조 및 훼손을 파악하기 위하여 7개 등산로를 대상으로 1999년 8월에 조사를 실시한 결과는 다음과 같다 등산로 상에 나타난 주연부식생의 주요 수종으로는 철쭉꽃 미역줄나무 조록싸리 등이었다 등산로 주연부의 종다양도 식생피도 개체수는 이용객 수와 깊은 상관관계는 없는 것으로 나타났다 입지환경별 드산로 주연부식생의 종구성은 남삼면과 북사면의 중복부에서 가장유사한 반면 동사면 상복부와 북사면 산록부간에 이질적이었다 한편 남, 북 사면간 등산로 주연부식생은 각 사면 산록부에서 종구성이 가장 이질적이었다 남.북사면의 중복부에서 조록싸리 철쭉꽃이 우세하였으나 북사면 상복부에서는 철쭉꽃이 우세하게 나타났다 등산로 주연부의 식생피도 능선부 남사면 북사면 동사면 순으로 높게 나타났다.

• Korean Journal of Environment and Ecology
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• v.24 no.5
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• pp.601-610
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• 2010

This study was carried out to classify vegetation structure of the southern and northern slopes in the Deogyusan National Park using TWINSPAN classification and DCCA ordination analysis. The vegetation on the southern slope was classified into Quercus mongolica community, Q. serrata community, Q. variabillis community, Pinus densiflora community, Carpinus laxiflora community, Cornus controversa community and Fraxinus mandshurica community. The vegetation on the northern slope was classified into Q. mongolica community, Q. serrata community, P. densiflora community, C. laxiflora community, Betula davurica community, C. controversa community, F. mandshurica community, B. costata community, Abies koreana community and Taxus cuspidata community. To find out important value in each slope, we took 103 districts on the southern slope and 137 districts on the northern slope. As the result, Q. mongolica was highest value in the southern and northern slopes, followed by P. densiflora, Q. serrata, Q. variabillis, Styrax obassia, Acer pseudosieboldianum in the southern slope, F. mandshurica, A. pseudosieboldianum, Q. serrata, C. laxiflora, C. controversa, C. cordata, Rhododendron schlippenbachii in the northern slope. Species distribution and ecological features had differences between the southern and northern slopes communities. As the result of DCCA ordination analysis, sea level and water availability had high correlation with community distribution. Besides, T-N, O.M., exchangeable Ca and pH did in the southern slope. And exchangeable Ca, pH also did in the northern slope.

• Proceedings of the Acoustical Society of Korea Conference
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• 1995.06a
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• pp.228-231
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• 1995

반연속 HMM 음성인식 시스템의 화자 적응 성능 향상을 위해 코드북 변환 알고리즘을 제안하였다. 기존의 화자 적응 알고리즘으로는 새로운 화자의 적응 데이터 특징의 분포와 HMM 모수의 사전밀도를 함께 고려하는 베이시안 화자적응 알고리즘이 있다. 그러나 새로운 화자의 특징분포와 코드북 사전 밀도의 차이가 큰 경우 적응 데이터와 코드북간의 잘못된 대응 관계를 얻을 수 있으며, 기준 코드북에 필요 이상으로 많은 코드워드가 존재하는 경우 적응된 코드북에도 불필요한 코드워드 들이 남아 인식 과정에 혼란을 줄 수 있다. 이 문제점을 해결하기 위하여 제안된 코드북 변환 알고리즘에서는 주파수 영역의 포만트 정보를 이용하였다. 화자 적응을 수행하기 앞서 코드북의 켑스트럼으로부터 포만트를 추출해 내고, 이들의 분포를 적응 화자의 포만트 분포와 일치되도록 변환시켜 주었다. 이 변환된 포만트들로부터 다시 켑스트럼을 구하여 변환된 코드북을 얻고 이를 화자 적응의 초기 코드북으로 사용하였다. 제안된 알고리즘을 이용하였을 경우 코드북과 적응 화자의 음성 간의 정확한 대응관계를 찾을 수 있었고, 불필요한 코드워드들이 인식 과정에서 사용되지 않도록 변환되어 인식률이 향상되는 것을 실험을 통해 확인하였다.

• Journal of Astronomy and Space Sciences
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• v.26 no.1
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• pp.25-30
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• 2009

We report the relation between the solar activity and terrestrial climate change with the solar north-south asymmetry. For this purpose, we calculate sliding correlation coefficients between sunspot numbers and earth's mean annual temperature anomalies. Then, we compare the epoch that the sign of correlation changes with the epoch that the sign of the solar north-south asymmetry changes. We obtain that corresponding times are 1907 and 1985, respectively. Further more, these two epoches are well consistent with those of signs of the solar north-south asymmetry changes. We also obtain that the plot between sunspot numbers and temperature anomalies could be classified by 1907 and 1985. We conclude that temperature anomalies are shown to be negatively correlated with sunspot numbers when the southern solar hemisphere is more active: and vice versa.

• The Journal of the Acoustical Society of Korea
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• v.15 no.2
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• pp.5-11
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• 1996

The purpose of this paper is to propose a method improving the performance of a semi-continuous hidden Markov model(SCHMM) speaker adaptation system which uses Bayesian Parameter reestimation approach. The performance of Bayesian speaker adaptation could be degraded in case that the features of a new speaker are severely different from those of a reference codebook. The excessive codewords of the reference codebook still remain after adaptation proess. which cause confusion in recognition process. To solve such problems, the proposed method uses formant information which is extracted from the cepstral coefficients of the reference codebook and adaptation data. The reference codebook is adapted to represent the formant distribution of a new speaker and it is used for Bayesian speaker adaptation as an initial codebook. The proposed method provides accurate correspondence between reference codebook and adaptation data. It was observed that the excessive codewords were not selected during recognition process. The experimental results showed that the proposed method improved the recognition performance.

• Journal of Korean Society of Forest Science
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• v.85 no.1
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• pp.107-119
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• 1996

To understand vegetation changes along environmental gradients in the natural forests in the east side of the Cascade Range in Washington state, USA, line transects were used to sample six different forest environments in the Wenatchee National Forest in the north-facing and south-facing sites at 975, 1280 and 1700m elevation. Data were analyzed using ordination by detranded correspondence analysis. Pseudotsuga menziesii was found as one of the dominant species on all the six sites regardless of elevation or aspect, while Pinus ponderosa was dominant on south slopes only. Abies grandis and A. lasiocarpa were dominant species on north slopes at elevations of 1280 and 1700m, respectively. Moisture, as it related to aspect, was identified as one of the most important environmental gradients for explaining the variation of vegetation types. On north-facing slopes, compared to south-facing slopes, where moisture was not as limiting and canopies could grow denser, probably, elevation or competitive interaction was more important. Species diversity tended to decrease with increasing environmental severity, with south slopes having less diversity than north slopes due to extended water stress and harsher temperature extremes on south slopes. The age structure on north-facing and south-facing slopes was different. Light intensity, moisture and climate were different between these two slopes. Large scale disturbances(e.g., big fire or insects) were major causes in changing age structure. Younger trees showed a closer relationship between size and age than adult trees. DBH values of shade intolerant species in south-facing slope were bigger than those of north-facing slope, which suggested that aspect of stands be the most important factor for age and size.

• Journal of the Korean association of regional geographers
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• v.10 no.2
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• pp.371-388
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• 2004

EU is enlarging geographically by the process of expansion and is intensifying the economic bloc by the formation of European Union and European Monetary Union. This situation increases the direct investment in the intra-EU members and changes the intra-EU flows. First, EU is formed by the economic geographical space of the North and the South with a differentiation of economic factors and the degree of economic development. The North played a leading role for an augmentation of the intra-EU direct investment after the formation of EU. Second, the manufacturing industry of the intra-EU direct investment by industry was increased remarkably. In the intra-EU direct investment flow by region and industry, the South made relatively an outflow of the service industry and an inflow of the manufacturing industry. But the North made an outflow of the manufacturing industry and an inflow of the service industry. Third, in the intra-EU direct investment flows by manufacturing industry, the North concentrated in the petro-chemistry, metal-machinery and agro-food industry, however, the South which have relatively weak competitiveness compared to the North tends to show balanced investment patterns in all industries.

• Korean Journal of Agricultural and Forest Meteorology
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• v.5 no.4
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• pp.233-237
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• 2003

This study was conducted to provide a rational forest management method for a natural oak (Quercus variavilis) forest stand in the central part of South Korea based on characteristics of growth and water relation parameters. Average volume per hectare was 175.1 ㎥ in the study site of oak stands. Basal area and volume of each direction appeared to increase as the slope direction moves from north to south, but annual mean increment and periodic annual increment of DBH for 10 years showed the lowest value at the southern aspect. Maximum water potentials measured between 12 and 14 o'clock were analyzed by direction and elevation in the oak stands. Water potential of oak decreased as the slope changed from the north to the south aspect and water potential increased at lower elevations. Soil water content for the oak stands tended to decrease as the aspect shifted from north to south. Water potential and soil moisture content were highly correlated. It appears that oaks have a higher moisture requirement at the southern aspect, because of stand density related to intraspecific competition.