• Korean Journal of Fisheries and Aquatic Sciences
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• v.29 no.1
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• pp.97-106
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• 1996

Macroalgal community was analysed from December 1993 to October 1994 in Yonggwang vicinity, western coast of Korea. A total 51 species (12 green, 11 brown and 29 red algae) of marine algae were identified. Among four localities, the number of species observed was the highest as 34 species at Shimwon and the least as 31 species at Sunchanggum and Gamakdo. Seasonally, the number of species observed was the highest as 42 species in winter and the least as 18 species in summer. The species showing relatively high important value were Enteromorpha compressa, Sargassum thunbergii, Corallina pilulifera and Carpopeltis affinis, which were all common to four investigated localities. Seasonal and regional fluctuations of mean biomass was $66.0\~820.0\;g-wet\;wt/m^2$ at Hyanghado, $248.3\~886.3\;g-wet\;wt/m^2$ at Sunchanggum, $154.5\~510.2\;g-wet\;wt/m^2$ at Gamakdo and $85.0\~451.9\;g-wet\;wt/m^2$ at Shimwon, respectively. The flora investigated could be classified into six functional groups such as coarsely branched form $(41.2\%)$, sheet form $(25.5\%)$, filamentous form $(19.6\%)$, thick leathery $(7.8\%)$, crustous form $(3.9\%)$ and jointed calcarious form algae $(2.0\%)$. At the effluent area of the nuclear power plants, the algal composition of functional groups may affect species composition due to thermal pollution.

• Journal of Korea Water Resources Association
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• v.42 no.2
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• pp.149-160
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• 2009

The objective of this study is to suggest parameter regionalization scheme which is integrated two multivariate statistical methods: principal components analysis(PCA) and hierarchical cluster analysis(HCA). This technique is to apply semi-distributed rainfall-runoff model on ungauged catchments. 7 catchment characteristics (area, mean altitude, mean slope, ratio of forest, water content at saturation, field capacity and wilting point) are estimated for 109 mid-sized sub-basins. The first two components from PCA results account for 82.11% of the total variance in the dataset. Component 1 is related to the location of the catchments relevant to the altitude and Component 2 is connected with the area of these. 103 ungauged catchments are clustered using HCA as the following 6 groups: Goesan 23, Andong 6, Imha 5, Hapcheon 21, Yongdam 4, Seomjin 44. SWAT model is used to simulate runoff and the parameters of the model on the 6 gauged basins are estimated. The model parameters were regionalized for Soyang, Chungju and Daecheong dam basins which are assumed as ungauged ones. The model efficiency coefficients of the simulated inflows for these three dams were at least 0.8. These results also mean that goodness of fit is high to the observed inflows. This research will contribute to estimate and analyze hydrologic components on the ungauged catchments.

• The KIPS Transactions:PartD
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• v.11D no.3
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• pp.709-716
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• 2004

This paper describes an intelligent real-time monitoring system of a semiconductor processing equipment, which determines normal or not for a wafer in processing, using multiple time-series pattern recognition. The proposed system consists of three phases, initialization, learning and real-time prediction. The initialization phase sets the weights and tile effective steps for all parameters of a monitoring equipment. The learning phase clusters time series patterns, which are producted and fathered for processing wafers by the equipment, using LBG algorithm. Each pattern has an ACI which is measured by a tester at the end of a process The real-time prediction phase corresponds a time series entered by real-time with the clustered patterns using Dynamic Time Warping, and finds the best matched pattern. Then it calculates a predicted ACI from a combination of the ACI, the difference and the weights. Finally it determines Spec in or out for the wafer. The proposed system is tested on the data acquired from etching device. The results show that the error between the estimated ACI and the actual measurement ACI is remarkably reduced according to the number of learning increases.

• The Journal of the Korea Contents Association
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• v.21 no.12
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• pp.896-905
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• 2021

In the field of SIEM(Security information and event management), many studies try to use a feedback system to solve lack of completeness of training data and false positives of new attack events that occur in the actual operation. However, the current feedback system requires too much human inputs to improve the running model and even so, those feedback from inexperienced analysts can affect the model performance negatively. Therefore, we propose "active model improving feedback technology" to solve the shortage of security analyst manpower, increasing false positive rates and degrading model performance. First, we cluster similar predicted events during the operation, calculate feedback priorities for those clusters and select and provide representative events from those highly prioritized clusters using XAI (eXplainable AI)-based event visualization. Once these events are feedbacked, we exclude less analogous events and then propagate the feedback throughout the clusters. Finally, these events are incrementally trained by an existing model. To verify the effectiveness of our proposal, we compared three distinct scenarios using PKDD2007 and CSIC2012. As a result, our proposal confirmed a 30% higher performance in all indicators compared to that of the model with no feedback and the current feedback system.

• Journal of the Korean Society for Library and Information Science
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• v.57 no.3
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• pp.191-210
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• 2023

The purpose of this study is to draw implications through domestic and international best case studies of library programs, and to suggest ways to improve a public library reading programs through analysis based on the 3rd Reading Culture Promotion Basic Plan in line with the changing role of future libraries. there is To this end, first, prior studies were analyzed from various angles to derive clustering standards for library programs. Based on this, programs of various domestic and foreign libraries were analyzed based on clustering criteria. And based on the clustering criteria of library programs and the 13 key tasks under the 4 strategies of the 3rd Reading Culture Promotion Basic Plan, the status of a specific public library reading programs was analyzed. Through this, in consideration of the demand of users in the era of the 4th Industrial Revolution, participatory reading promotion programs are expanded, and in response to the post-COVID-19 era, beyond face-to-face library services, non-face-to-face and non-contact library services are also considered. A development plan was presented. It is expected that this analysis and application attempt will ultimately go beyond the unit library and contribute to improving the public library service in Korea into a library program closely related to the lives of users.

• Journal of the Korea Society of Computer and Information
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• v.25 no.9
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• pp.151-158
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• 2020

The purpose of this study was to analyze the characteristics of each type after categorizing the clothing lifestyle of 394 male office workers in their 30s and 50s. The data were analyzed with PASW 18.0 using frequency analysis, k-means cluster analysis, one-way ANOVA and crosstabs analysis. According to findings, first of all, types of clothing lifestyle are divided into 4 groups: a type of fashion leader(22.3%), a type of price sensitive(12.2%), a type of fashion indifference(27.9%), a type of normcore fashion(37.6%). Secondly, the types of clothing lifestyle showed statistically significant difference age, marital status, job and monthly average household income of socio-economic variables. Thirdly, the types of clothing lifestyle showed statistically significant difference monthly average appearance care cost, suit count, monthly average clothing purchase cost, average purchase cost of one suit.

• The Journal of the Korea Contents Association
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• v.14 no.8
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• pp.406-415
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• 2014

In this study, the fast-growing market in the Food Service Industry Study of the delivery service. The first objective of this study is to classify consumers food-related lifestyle and the second is the dimension of the delivery service quality will derive. According to the consumer's food-related life style, make about the consumer's delivery service quality perception and satisfaction to evaluate the differences. Food-related lifestyle 'health seeking type', 'fashion pursuit type', 'type taste pursue', 'seek safety-type', 'seek convenience-type' was separated, cluster analysis 'taste pursuit group', 'high-interest in foods group', 'seek convenience-group' were classified. Delivery service quality 'food quality', 'economic', 'ease of ordering', 'employee quality', 'sanitation', 'order quality' and were classified into six. That of 'food quality' and 'economic' factor were significantly different from the consumer group, but also the 'order quality', 'food quality', 'sanitation' and the order of the large degree of influence on satisfaction, respectively.

• Korean Journal of Childcare and Education
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• v.8 no.5
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• pp.111-127
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• 2012

The purpose of this study was to investigate the effects of directors' leadership and teachers' self leadership on teachers' efficacy. The participants were 217 teachers in private day care centers. LBDQ (Halpin, 1967), RSLQ (Houghton & Neck, 2002), and a teachers' efficacy questionnaire (Kim & Lee) were used. The data collected were analyzed by SPSS 18.0. The results of this study were as follows: First, teachers cognized that directors' leadership was very high. Second, directors' leadership was clustered by 4 types: human oriented, task oriented, leader and deficient type. And, teachers' efficacy was clustered by 4 types: leader, restricted, compensated and task oriented type. Third, directors' task oriented leadership, human oriented leadership, and teachers' self leadership (self punishment, self-goal setting, self observation and self esteem) affected teachers' efficacy. And directors' human oriented leadership and teachers' self leadership (self punishment and self-goal setting) affected teachers' personal efficacy.

• The Korean Journal of Applied Statistics
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• v.32 no.6
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• pp.837-849
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• 2019

Latent class models (LCM) are useful tools to draw hidden information from categorical data. This model can also be interpreted as a mixture model with multinomial component distributions. In some cases, however, an available dataset may contain both categorical and count or continuous data. For such cases, we can extend the LCM to a mixture model with both multinomial and other component distributions such as normal and Poisson distributions. In this paper, we consider a LCM for the data containing categorical and count data to analyze the Drug Review dataset which contains categorical responses and text review. From this data analysis, we show that we can obtain more specific hidden inforamtion than those from the LCM only with categorical responses.

• Journal of Digital Convergence
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• v.12 no.5
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• pp.345-351
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• 2014

The purpose of this study was to identify the difference between job satisfaction and organizational commitment by the type of time management behavior in clinical nurses. Total 208 nurses were recruited from clinical settings where located in Seoul and Daejeon, South Korea. Data were collected using self-administered method with structured questionnaire between August 2012 and January 2013. Descriptive statistics, K-mean cluster analysis, one-way ANOVA were performed for data analysis. As results, the type of time management behavior were classified into four types such as unconcern type, accomplishment type, urgency type and selection & concentration type. Among four types, nurses who belonged to be accomplishment and selection & concentration type were tend to have positive behaviors in terms of time managements as they had high scores in job satisfaction. Therefore, further study on whether types of time management are related with organizational culture including commitment and effectiveness should be explored.