• Journal of Astronomy and Space Sciences
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• v.22 no.4
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• pp.393-408
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• 2005

We developed and compared two automatic algorithms for moving object detections in the YSTAR-NEOPAT sky survey program. One method, called starlist comparison method, is to identify moving object candidates by comparing the photometry data tables from successive images. Another method, called image subtraction method, is to identify the candidates by subtracting one image from another which isolates sources moving against background stars. The efficiency and accuracy of these algorithms have been tested using actual survey data from the YSTAR-NEOPAT telescope system. For the detected candidates, we performed eyeball inspection of animated images to confirm validity of asteroid detections. Main conclusions include followings. First, the optical distortion in the YSTAR-NEOPAT wide-field images can be properly corrected by comparison with USNO-B1.0 catalog and the astrometric accuracy can be preserved at around 1.5 arcsec. Secondly, image subtraction provides more robust and accurate detection of moving objects. For two different thresholds of 2.0 and $4.0\sigma$, image subtraction method uncovered 34 and 12 candidates and most of them are confirmed to be real. Starlist comparison method detected many more candidates, 60 and 6 for each threshold level, but nearly half of them turned out to be false detections.

• Korean Journal of Agricultural and Forest Meteorology
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• v.8 no.2
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• pp.86-96
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• 2006

Ecoclimap-1, a new complete surface parameter global database at a 1-km resolution, was previously presented. It is intended to be used to initialize the soil-vegetation- atmosphere transfer schemes in meteorological and climate models. Surface parameters in the Ecoclimap-1 database are provided in the form of a per-class value by an ecoclimatic base map from a simple merging of land cover and climate maps. The principal objective of this ecoclimatic map is to consider intra-class variability of life cycle that the usual land cover map cannot describe. Although the ecoclimatic map considering land cover and climate is used, the intra-class variability was still too high inside some classes. In this study, a new strategy is defined; the idea is to use the information contained in S10 NDVI SPOT/VEGETATION profiles to split a land cover into more homogeneous sub-classes. This utilizes an intra-class unsupervised sub-clustering methodology instead of simple merging. This study was performed to provide a new ecolimatic map over Northeast Asia in the framework of Ecoclimap-2 global database construction for surface parameters. We used the University of Maryland's 1km Global Land Cover Database (UMD) and a climate map to determine the initial number of clusters for intra-class sub-clustering. An unsupervised classification process using six years of NDVI profiles allows the discrimination of different behavior for each land cover class. We checked the spatial coherence of the classes and, if necessary, carried out an aggregation step of the clusters having a similar NDVI time series profile. From the mapping system, 29 ecosystems resulted for the study area. In terms of climate-related studies, this new ecosystem map may be useful as a base map to construct an Ecoclimap-2 database and to improve the surface climatology quality in the climate model.

• Journal of the Korean association of regional geographers
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• v.21 no.3
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• pp.583-592
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• 2015

As the increase of an environmental disease has become a social problem after industrialization, academic interest in a spatial difference and characteristics of an environmental disease is on rise. The purpose of this study is to analyze the spatial distribution and characteristics of an environmental disease using the data provided by National Health Insurance Corporation in 2009. This research is focusing on atopic dermatitis among a variety of environmental diseases and shows the map that atopic dermatitis patients are distributed. Also, The Local Moran's I show how spatial autocorrelation of atopic dermatitis patients are distributed. First, the distribution of atopic dermatitis patients show the spatial difference. Second, 42 places including the western part of Incheon are hot spots of atopic dermatitis. Third, 39 places including Danyang are cold spot of atopic dermatitis. Forth, Jeju-si and Seogwipo-si are unusually hot spot of atopic dermatitis. These results have important implications that further research need to be done in public health geography.

• Journal of the Korean BIBLIA Society for library and Information Science
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• v.26 no.4
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• pp.245-262
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• 2015

As the topics of general education in universities become more diverse, it is not an easy task to identify the topics of general education courses. This study aims to identify and visualize the topics of A university's general education courses using informetric analysis methods. 214 syllabi were collected and titles, course introduction, goals, and weekly plans were analyzed. 278 topic words were extracted from the data set and grouped into 8 clusters. In the network analysis, topic clusters were divided into two areas, personal and social. Personal area has 14 sub-topic clusters and social area has 11 sub-topic clusters. In personal area, 'language', 'science', and 'personality' were major topic clusters. In social area, 'multi-culture' cluster was the core cluster with connected to four other clusters. The topic network generated in this study can be used for the university and the university library to enhance general education or to develop collections for general education.

• Journal of Korean Society of Forest Science
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• v.90 no.4
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• pp.573-581
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• 2001

The purposes of this study are to estimate mean willingness to pay (WTP) for preventing forest fires by contingent valuation method (CVM), and to calibrate the variables affecting WTP. The forest fire prevention fund was utilized as a payment vehicle to elicit respondents' willingness to pay (WTP). A total of 500 adults who reside in Seoul Metropolitan area were selected by two-stage cluster sampling and conducted the face-to-face interview. The scenario was designed to meet the requirements for double-bounded dichotomous choice CVM. More than half of the respondents (64.6%) have a willing to pay for the fund. The mean WTP was \4,532. Therefore a total WTP for the population was \34,165,758,000. The calibration of Weibull proportional hazard model showed that education level, environmental conservation intention and negative consciousness about the effect of forest fire were independent variables strongly influencing the WTP.

• 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.20 no.11
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• pp.110-118
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• 2020

Social media data serves as a proxy indicator to understand the problems and the future of public opinion in Korean society. This research used 109,015 news data from 2016 to 2018 to analyze the sensitivity of the elderly and employment in Korean society, and explored the possibility of expanding the labor force in Korean society, which is facing a cliff between the elderly and the population. Topic keywords for employment of the elderly include "elderly*employment", "elderly*employment", and "elderly*wage". As a result of the analysis, positive sensitivity prevails for most of the period, and it is possible to expand the working-age population. Positive feelings about expanding employment opportunities for the elderly and negative feelings about low wages have brought to light the reality of the elderly who are still poor despite their work. In this study, social big data was used to analyze the perceptions and sensibilities of Korean society related to the elderly and employment through hierarchical crowd analysis and related text mining analysis.

• Journal of the Korean Association of Geographic Information Studies
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• v.4 no.4
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• pp.1-7
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• 2001

Remotely sensed data is the most fundamental data in acquiring the GIS informations, and may be analyzed to extract useful thematic information. Multi-spectral classification is one of the most often used methods of information extraction. The actual multi-spectral classification may be performed using either supervised or unsupervised approaches. This paper analyze the effect of assigning clever initial values to image classes on the performance of parallelepiped classification algorithm, which is one of the supervised classification algorithms. First, we investigate the effect on serial computing model, then expand it on MIMD(Multiple Instruction Multiple Data) parallel computing model. On serial computing model, the performance of the parallel pipe algorithm improved 2.4 times at most and, on MIMD parallel computing model the performance improved about 2.5 times as clever initial values are assigned to image class. Through computer simulation we find that initial values of image class greatly affect the performance of parallelepiped classification algorithms, and it can be improved greatly when classes on both serial computing model and MIMD parallel computation model.

• Korean Journal of Childcare and Education
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• v.11 no.1
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• pp.153-171
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• 2015

The purposes of this study were to explore the relations of preschoolers' narrative representation profile types to diurnal cortisol regulation pattern at home. Fourteen story stems from the MacArthur Story Stem Battery (MSSB, Bretherton, et al., 1990) were administered to 40 preschoolers(22 boys, 18 girls, aged 5) recruited from 8 kindergartens in the Seoul and Gyeonggi areas. And also, their saliva cortisol was collected. The children's responses were aggregated into 5 dimensions, based on content themes and performance scores, which included emotions expressed and narrative coherence using the MacArthur Narrative Coding System(Robinson, et al., 2004). Data were analyzed by means of cluster analysis. Five response profiles emerged over the course of this research: Prosocial, Anxiety, Dyregulated aggression, Restricted, and Avoidance profiles. Cortisol at home showed decrease diurnal cortisol regulation patterns, however it showed a difference according to narrative response profiles. Restricted, Prosocial, and Avoidance profiles showed decrease diurnal cortisol regulation patterns. Anxiety profiles showed flat pattern, and Dyregulated aggression profile showed rising diurnal cortisol regulation pattern. These results show the preschoolers' internal representation may affect the diurnal cortisol reaction in daytime.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.22 no.6
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• pp.125-138
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• 2019

This study aims to highlight the possibility in identifying species composition of fish communities using the environmental DNA (eDNA) metabarcoding technique, from both of the technical introduction and the pilot test at urban ecological streams. This new emerging survey technique using eDNA is getting popular in the world as a compensating way for the conventional field survey. However, the application to the domestic cases has yet to be studied. We attempted to use this technique for identifying fish species observed at four survey points in Hwangguji-chon, Suwon City. As a result, the detected number of species by eDNA sampled once in May was significantly matched with the total number of observed species in annual field surveys. Additionally eDNA results indicated the presence possibility of the unobserved species in field last year, even though the validation may be required. This survey technique seems to be more efficient and applicable to diverse situations of the fields and species, thereby needs to be studied further. We discussed the pros and cons of the application and summarized the research directions in future.