• Korean journal of communication and information
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• v.34
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• pp.275-305
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• 2006

The main research question of this paper is as follows: How can broadcasting both cause the crisis in democratic participation and yet also offer the solution? The contradiction in broadcast localism has never been adequately resolved in spite of regulation at all in practice, in that localism simply cannot account for the diversity of modern life and for the external forces that incorporate local communities into much larger economic and communications network. The concept of locality in local television, however, has been multiplied and enlarged in order to adjust to "time-space compression". Recently the local television have been "interface" combining and negotiating the globalization of media market and the decentralization of political power, the economies of scale and the activation of local democracy, consequently aiming at the horizontal-cooperative network instead of old vertical-dependent one.

• Journal of Korea Port Economic Association
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• v.33 no.4
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• pp.17-36
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• 2017

In the modern economic context, it is apparent that there is a strong focus on the importance of global shipping industry. Recently, the world economic crisis has negatively influenced the industry with regard to both supply and demand, which has seen almost no sign of recovery. The fact that the entire industry is operating with low efficiency and at a low profit state has made all stakeholders anxious. This research examines the financial performance of the world's major shipping lines in order to give maritime stakeholders a closer look into the industry behind the ranking. Besides, the research evaluates the competitiveness of shipping companies in terms of financial ability and suggestions for strategic actions to stakeholders are provided. For these purposes, Fuzzy-C Means is used to cluster the selected lines into different groups based on their financial indices, namely liquidity, asset management, debt management and profitability. Levene's tests which are then followed by ANOVA tests are also utilized to assess the robustness of the clustering outcomes. The results indicate that liquidity, solvency and profitability act as the main criteria in the classification problem.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.12 no.4
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• pp.772-780
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• 2008

K-means is one of the simplest unsupervised learning algorithms that solve the clustering problem. However K-means suffers the basic shortcoming: the number of clusters k has to be known in advance. In this paper, we propose extensions of X-means, which can estimate the number of clusters using Bayesian information criterion(BIC). We introduce two different versions of algorithm: modified X-means(MX-means) and generalized X-means(GX-means), which employ one full covariance matrix for one cluster and so can estimate the number of clusters efficiently without severe over-fitting which X-means suffers due to its spherical cluster assumption. The algorithms start with one cluster and try to split a cluster iteratively to maximize the BIC score. The former uses K-means algorithm to find a set of optimal clusters with current k, which makes it simple and fast. However it generates wrongly estimated centers when the clusters are overlapped. The latter uses EM algorithm to estimate the parameters and generates more stable clusters even when the clusters are overlapped. Experiments with synthetic data show that the purposed methods can provide a robust estimate of the number of clusters and cluster parameters compared to other existing top-down algorithms.

• Korean Journal of Environment and Ecology
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• v.8 no.2
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• pp.150-153
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• 1995

A Pinus densiflora forest in Chuwangsan was studied to determine the adequate plot area of shrub stratum for investigating forest community structure. Nineteen nested plots were set up in the studied forest, and species-area curve and performance curve were established. According to species-area curve, the minimum plot area where a given percentage increase in plot area produced less than the same percentage increase in number of species was 900$m^2$. The minimum plot area where a given percentage increase in plot area produced less than the half of the percent-age increase in number of species was 1,500$m^2$. According to performance curve of the importance values of the major species, the minimum plot area where the importance value of the major species was distinguished from each other was 1,400$m^2$. According to performance curve of species diversity, the minimum plot area was 750-1,500$m^2$. Similarity indices between plot area above 900$m^2$ and total plot area were more than 90% and similarity indices between plot area above 625$m^2$ and total plot area were more than 85%. It may be given as a conclusion that minimum plot area was about 1,500$m^2$ in case of requiring more accuracy.

• Korean Journal of Social Welfare
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• v.57 no.1
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• pp.245-269
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• 2005

This paper purports to evaluate the public assistance programme of Korea in comparison with those of member states of the European Union, using the concept of poverty regime as a heuristic device. For this purpose, chapter two discusses notions of welfare-state regime (Esping-Andersen, 1990) and poverty regime(Sainsbury and Morissen, 2002). Chapter three examines poverty and income distribution in Korea and the member states of the EU, and chapter four compares and analyses the public assistance programme of those countries, using hierarchical cluster analysis. It claims that the 'welfare paradox' of $L{\empty}delmel$ (1997) is not based on evidence, and duly concludes that the overall level of welfare effort such as welfare expenditure is a main determinant for the development of public assistance programmes.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.17 no.3
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• pp.149-159
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• 2012

To elucidate the species compositions of estuarine and inshore fauna and compare productivities between them, catch were collected by bag nets in the Han River estuary off Ganghwa Island and the inshore waters off Jangbong Island for 24 hours at the spring tide from March to December 2010. Community structures of nekton assemblages were different with area, month, taxonomic groups. Although the diversity of estuarine nekton assemblage was lower than that of inshore nekton assemblage, the productivity of nekton assemblage in estuary was higher than that in the inshore waters. Nekton assemblages were distributed according to habitat environment: the estuarine species, Coilia mystus, Chelon haematocheilus, Collichthys lucidus were prominent in the Han River estuary off Ganghwa Island, and marine species, Thryssa kammalensis, Sardinella zunasi, Portunus trituberculatus were prominent in the inshore waters off Jangbong Island. Palaemon gravieri, Exopalaemon carinicauda, Synechogobius hasta were inhabited in both waters. The health assessment of estuarine ecosystem based on scientific research will be contributed to the effective management of estuary with determination of order and direction in policy.

• Korean Journal of Ecology and Environment
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• v.33 no.3 s.91
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• pp.197-205
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• 2000

Factors most strongly related to zooplankton growth rates were studied along a lake and a river stretch in the middle part of the lowland River Spree. The study was conducted at the lake inflow (S1), the lake outflow (S2), and at the end of a 21 km stretch of the outflow (S3) from March to November of 1999. Total zooplankton biomass increased significantly at S2 and then sharply decreased at S3. The abundance of microzooplankton (rotifers and nauplii) was strongly higher than macrozooplankton (cladocerans and copepodids) at all station. However, macrozooplankton biomass (${\mu}$g dw 1$^{-1}$) was similar or much higher than microzooplankton biomass. Large-bodied cladocerans (Daphnia cucullata) dominated at S2 while small-bodied cladocerans (Bosmina longirostris) dominated at S1 and S3. Patterns in growth rates (r$_{t}$ in d$^{-1}$ of the major zooplankton community were greatly different between S1 and S2 (lake stretch) and between S2 and S3 (river stretch). In the lake, growth rates generally were positive, while values of growth rates were negative in the river stretch. Among the environmental variables considered, partial retention time (PRT, d$^{-1}$) seemed to play the most important role in determining characteristics of the zooplankton community structure in the middle part of River Spree.

• Journal of Korean Society for Geospatial Information Science
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• v.4 no.2 s.8
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• pp.181-193
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• 1996

A new technique for land cover classification which applies digital image pre-classified by unsupervised classification technique, clustering, to Canonical Correlation Analysis(CCA) was proposed in this paper. Compared with maximum likelihood classification, the proposed technique had a good flexibility in selecting training areas. This implies that any selected position of training areas has few effects on classification results. Land cover of each cluster designated by CCA after clustering is able to be used as prior information for maximum likelihood classification. In case that the same training areas are used, accuracy of classification using Canonical Correlation Analysis after cluster analysis is better than that of maximum likelihood classification. Therefore, a new technique proposed in this study will be able to be put to practical use. Moreover this will play an important role in the construction of GIS database

• Proceedings of the Korea Water Resources Association Conference
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• 2007.05a
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• pp.1219-1223
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• 2007

수온은 수계에서 가장 중요한 물리적 특성 중 하나로서, 생물 군집, 특히 어류와 무척추 동물에 관련된 많은 수질 인자에 영향을 미친다. 하천의 생태학적 모습을 개선하기 위한 하천 복원 사업 수행에 있어서, 서식처 및 산란처 조건으로서의 수온 조사 및 모델링의 필요성이 점차 증가하고 있는 상황이다. 본 연구는 낙동강의 중상류에 위치한 반변천 합류부에 평면 이차원 비정상 수치모형인 KU-RLMS 모형을 적용하여 수온의 변화 특성을 규명할 목적으로 수행하였다. KU-RLMS 모형은 하천 및 저수지의 국부적인 수리, 수질, 유사이동 해석을 위해 개발된 평면 이차원 비정상 수치모형이다. 직사각형 격자를 사용하는 유한차분법의 단점을 보완하기 위해, 수심적분된 2차원 연속방정식, 운동량방정식, 이송확산방정식을 불규칙한 경계를 현실적으로 모사할 수 있는 직교곡선 좌표계로 변환한 방정식을 사용한다. 이 모형은 흐름, 농도, 지형변화를 조합하여 계산할 수 있는 모형으로서 점착성 및 비점착성 유사의 이동, 보존성 및 비보존성 오염물질의 이동, 수온 변화를 모의할 수 있다. 수치모형 적용을 위한 현황분석으로 안동 및 임하 조정지댐의 방류량, 안동 수위관측소의 수위, 법흥교 및 포진교 지점의 수온 자료를 분석하였다. 이송확산모형의 보정을 위해, 안동대교 지점의 수온 횡분포 측정자료를 사용하여 확산계수에 대한 매개변수 추정 및 검증을 수행하였다. 또한, 안동조정지댐과 임하조정지댐의 방류량 및 방류수온을 고려하여 수치모의조건을 결정하였으며, 각 조건에 대한 수온 변화 특성을 분석하였다.

• Journal of Korean Society of Forest Science
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• v.78 no.3
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• pp.255-262
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• 1989

Vegetation data of the mixed mesophytic forest in Mt. Chombong area were analyzed by the methods of classification and ordination. 'Weighted group average linkage cluster analysis' recognized five distinctive vegetation groups, based on the abundance data of 83 woody plant species in 70 sampling units. The species diversity was also examined for each group. The importance values of 42 tree species in the groups were subjected to principal component analysis (PCA). The PCA ordinated five vegetation groups on the first two axes, so as to compare similarity among them in terms of species composition. Acer palmatum, Fraxinus rhynchophylla, Quercus mongolica, and Acer mono had greatest influence on the determination of group scores with high eigenvectors (component loadings) in the first axis. Distribution of these four dominant species appeared to be important in determining community association in this diversified forest.