• Journal of Institute of Control, Robotics and Systems
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• v.22 no.4
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• pp.253-265
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• 2016

We propose an obstacle classification method using multi-decision factors and decision sections based on Single 2D LiDAR. The existing obstacle classification method based on single 2D LiDAR has two specific advantages: accuracy and decreased calculation time. However, it was difficult to classify obstacle type, and therefore accurate path planning was not possible. To overcome this problem, a method of classifying obstacle type based on width data was proposed. However, width data was not sufficient to enable accurate obstacle classification. The proposed algorithm of this paper involves the comparison between decision factor and decision section to classify obstacle type. Decision factor and decision section was determined using width, standard deviation of distance, average normalized intensity, and standard deviation of normalized intensity data. Experiments using a real autonomous vehicle in a real environment showed that calculation time decreased in comparison with 2D LiDAR-based method, thus demonstrating the possibility of obstacle type classification using single 2D LiDAR.

• Journal of Positioning, Navigation, and Timing
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• v.12 no.2
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• pp.201-209
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• 2023

Time comparison techniques are required for generating and keeping Coordinated Universal Time (UTC) and to distribute standard clocks. These techniques play an important role in various fields, including science, finance, military, and communication. Among these techniques, Two-Way Satellite Time and Frequency Transfer (TWSTFT) ensures a relatively high accuracy, with a time comparison accuracy at a nanosecond level. However, TWSTFT systems have some limitations, such as the dependency on extra network links. In this paper, we propose an improved method for TWSTFT system operation and design a message structure for the suggestion. Additionally, we estimate the data rate and redundancy for the new TWSTFT signal with the designed message structure.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2021.05a
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• pp.563-565
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• 2021

The most important feature of the recently increasing content providing service is that the amount of content increase over time is very large. Accordingly, the importance of user curation is increasing, and various techniques are used to implement it. In this paper, among the techniques for video recommendation, the analysis technique using voice data and subtitles and the video comparison technique based on keyframe extraction are compared with the results of implementing and applying the video content of real big data. In addition, through the comparison result, a video content environment to which each analysis technique can be applied is proposed.

• Human Ecology Research
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• v.57 no.1
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• pp.127-142
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• 2019

This study investigates factors that impact dating relationship stability(DRS) among college students by applying two key concepts from the Interdependence Theory suggested by Kelly & Thibaut (1978; Thibaut & Kelly, 1959), the comparison level(CL) and comparison level for alternatives($CL_{alt}$). This study also examined mediating effects of commitment on the relationship between CL and DRS and $CL_{alt}$ and DRS. The research used a survey data set drawn from 327 college students currently involved in a dating relationship. The collected data set was then analyzed using SPSS software ver. 23.0 and AMOS software ver. 25.0, to produce the descriptive statistics, Pearson's correlations, and path analysis with bootstrapping. First, both CL and $CL_{alt}$ had a significant direct impact on DRS. In terms of effect size, CL's effect size was comparatively larger than $CL{_{alt}}'s$. The mediating effects from the commitment were evidenced. In the model, the commitment partially mediated the relationships between CL and DRS, and $CL_{alt}$ and DRS. The findings suggest that commitment still plays a key role in dating relationships among college students who currently have a romantic partner. The findings of this study show the possibilities in applying the concepts and theory of interdependence to explain current dating relationships among young adults.

• Atmosphere
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• v.26 no.4
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• pp.649-663
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• 2016

This study investigates eddy transports in terms of space and time for momentum, heat, and moisture, emphasizing comparison of the results in three reanalysis data sets including ERA-Interim from the European Center for Medium-range Weather Forecasts (ECMWF), NCEP2 from the National Center for Environmental Prediction and the Department of Energy (NCEP-DOE), and JRA-55 from the Japan Meteorological Agency (JMA) during boreal winter. The magnitudes for eddy transports of momentum in ERA-Interim are represented as the strongest value in comparison of three data sets, which may be mainly come from that both zonal averaged meridional and zonal wind tend to follow the hierarchy of ERA-Interim, NCEP2, and JRA-55. Whereas in relation to heat and moisture eddy transports, those of NCEP2 are the strongest, implying that zonal averaged air temperature (specific humidity) tend to follow the raking of NCEP2, ERA-Interim, and JRA-55 (NCEP2, JRA-55, and ERA-Interim), except that transient eddy transports for heat in ERA-Interim are the strongest involving both meridional wind and air temperature. The stationary and transient eddy transports in the context of space and time correlation, and intensity of standard deviation demonstrate that the correlation (intensity of standard deviation) influence the structure (magnitude) of eddy transports. The similarity between ERA-Interim and NCEP2 (ERA-Interim and JRA-55) of space correlation (time correlation) closely resembles among three data sets. A resemblance among reanalysis data sets of space correlation is larger than that of time correlation.

• Herbal Formula Science
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• v.30 no.3
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• pp.183-189
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• 2022

Objective : This study aims to analyze the current use of body part terminology in Korean medicine formula data by comparing with ICD-11 body part terminology as a criteria. Methods : Body part terminology was extracted from the main treatment data within the Korean Medicine formula ontology and was analyzed in comparison with the ICD-11 body part terminology. Results : Out of 113 body part terminologies in Korean medicine, 92 were corresponded with ICD in a one-to-one, one-to-multi, or multi-to-one relation. Also, most body part terminologies were corresponded to superordinate concepts of ICD while 21 terminologies were not able to be corresponded to ICD. Conclusion : A majority of body part terminology in formula data could be corresponded to ICD but mostly refered to superordinate concepts. Results showed various types of corresponding relation which requires further study for precise and detailed correspondence. Also, study showed some terminologies were not applicable for correspondence which were mostly a unique body part concept of Korean medicine which requires further study to present Korean Medicine knowledge accurately in the language of ICD.

• Human Ecology Research
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• v.57 no.2
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• pp.295-305
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• 2019

This study examined the effects of social comparison orientation and stress coping styles on job-seeking stress experienced by university students. The participants of this study were 324 junior and senior students (151 males and 173 females) from six universities located in Seoul who were preparing for employment. They were asked to respond to a written questionnaire to measure research variables for the Job-Seeking Stress Scale, the Social Comparison Orientation Scale, and the Ways of Coping Checklist. The data were analyzed by means of descriptive statistics and a hierarchical multiple regression. The major findings of this study were as follows. First, social comparison orientation had a positive effect on job-seeking stress of university students, revealing that students with a high level of social comparison orientation were more likely to experience job-seeking stress. Second, both emotion-alleviation coping style and wishful thinking coping style increased level of job-seeking stress. In addition, problem-focused coping style had a negative influence on job-seeking stress, whereas social support seeking coping style had no significant effect on it. The results suggested that it would be possible to reduce job-seeking stress of university students by changing either social comparison or stress coping style.

• Korea-Australia Rheology Journal
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• v.17 no.3
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• pp.111-116
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• 2005

The new tube model with variable diameter (Marrucci and Ianniruberto, 2004), recently introduced to interpret new elongational data of polymer melts, is here extended to encompass arbitrary flows, specifically shear flows. The predicted results compare well with existing data of entangled polymer melts. Challenges still remain when the comparison is extended to recent elongational data on entangled solutions by Sridhar.

• Journal of the Korean Data and Information Science Society
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• v.17 no.2
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• pp.437-447
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• 2006

Error Correcting Output Coding(ECOC) is used to solve multi-class problem. It is known that it improves the classification accuracy. In this paper, we compared various criteria to design code matrix while encoding. In addition. we prorpose an ensemble which uses the ability of each classifier while decoding. We investigate the justification of the proposed method through real data and synthetic data.

• Journal of the Korean Data and Information Science Society
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• v.17 no.3
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• pp.851-859
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• 2006

The family income distributions of NLSY97 and CPS youth data are compared by using the generalized beta distribution of the second kind. The null hypothesis that the two data sets represent the same underlying population is rejected. The ML estimation suggests that NLSY97 data are oversampled in an income group of $11,308 or less, by about 15.7% compared to CPS data.