• Proceedings of the Korean Nuclear Society Conference
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• 2001.10a
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• pp.175.2-175
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• 2001

• Water Engineering Research
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• v.2 no.1
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• pp.63-72
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• 2001

The variation of sampling errors was characterized using the Waymire-Gupta-Rodriguez-Iturbe multi-dimensional rainfall model(WGR model). The parameters used for this study are those derived by Jung et al. (2000) for the Han River Basin using a genetic algorithm technique. The sampling error problems considered are those for using raingauge network, satellite observation and also for both combined. The characterization of sampling errors was done for each month and also for the downstream plain area and the upstream mountain area, separately. As results of the study we conclude: (1) The pattern of sampling errors estimated are obviously different from the seasonal pattern of monthly rainfall amounts. This result may be understood from the fact that the sampling error is estimated not simply by considering the rainfall amounts, but by considering all the mechanisms controlling the rainfall propagation along with its generation and decay. As the major mechanism of moisture source to the Korean Peninsula is obviously different each month, it seems rather normal to provide different pattern of sampling errors from that of monthly rainfall amounts. (2) The sampling errors estimated for the upstream mountain area is about twice higher than those for the down stream plain area. It is believed to be because of the higher variability of rainfall in the upstream mountain arean than in the down stream plain area.

• Journal of the Korean Institute of Intelligent Systems
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• v.14 no.6
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• pp.674-677
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• 2004

This paper deals with a systematic approach for the construction of the fixed-delay tree search (FDTS) detector in the intersymbol interference channel. The approach is based on the efficient multi-dimensional space partitioning. The Voronoi diagram (VoD) and the Delaunay tessellation (DT) of the multi-dimensional space are applied to implement the algorithm. In the proposed approach, utilizing the geometric information contained in the VOD/DT, the relative location of the observation sequence is determined which has been shown to reduce the implementation complexity. Detailed construction procedures are discussed followed by an example from the intersymbol interference communication channel.

• The Journal of the Korea Contents Association
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• v.9 no.12
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• pp.622-629
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• 2009

Modern figurative work is designed to have more creativity and characteristic traits by pure thought of the formative ceramic arts. In compliance with the demand which is various the design development could be satisfied an individuality and a taste is become accomplished. In this view, this study looks over expressive aspect of Cubism to present partition as a independent formative ceramic arts is able to contribute emotionally to our whole lives. In this procedure, this work is produced to express a three-dimensional effect and a spatial effect, approaching a figurative side. This is to overcome the limitation of Cubism art expressed in a two-dimensional surface in spite of its multi-dimensional observation of a given object. Accordingly, this study tries approaching pre-understanding of expressive aspect of Cubism which was the important turning-point in 20c art and expansion of the modern ceramic art field before producing the work. This study shows the possibility to become a creative and practical ceramic art work, approaching the new point of view breaking from the established conception. Consequently, the field of ceramic art could be expanded to a part of modern ceramic art as an object of study in art of life.

• Journal of Korean Elementary Science Education
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• v.34 no.4
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• pp.458-475
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• 2015

The purpose of this study was to analyze the responses of pre-service elementary teachers to the plant learning using plant-observation activities and observation journal writings. Thirty pre-service teachers participated in this study. Before and after practicing plant observation and observation journal writing for 11 weeks, pre-service teachers' interest to plants, attitude to plant-observation teaching, and plant-observation teaching efficacy were examined using a questionnaire. Also, the observation journals, reflective journal writings, and interviews were analyzed to investigate their qualitative change. In addition, the pre-service teachers were classified by multi-dimensional scaling and cluster analysis with respect to attitude to plant-observation teaching and observation journal writing, and teaching efficacy. While the pre-service teachers showed significant increase of the interest to plants and plant-observation teaching efficacy, and positive change of the attitude to plant-observation teaching, there was a little difference between gender with more positive effects on females. The positive attitude changes of pre-service teachers included positive recognition about plants and the diversity, increased interest and curiosity about plants, careful observation about nearby plants, and independent learning and positive inquiry with plants. In terms of teaching efficacy, they showed positive change such as enjoyment and satisfaction with plant-observation, confidence as elementary teachers in the future, and recognition about the importance of elementary teachers for plant education. However, the changes were different among the groups classified by attitude to plant-observation teaching and observation journal writings, and plant-observation teaching efficacy.

• Korean Journal of Remote Sensing
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• v.35 no.5_1
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• pp.727-736
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• 2019

In this paper, we present how to create a point cloud for a target area using multiple unmanned aerial vehicle images and to remove the gaps and overlapping points between datasets. For this purpose, first, IBA (Incremental Bundle Adjustment) technique was applied to correct the position and attitude of UAV platform. We generate a point cloud by using MDR (Multi-Dimensional Relaxation) matching technique. Next, we register point clouds based on observation vectors between stereo images by doing this we remove gaps between point clouds which are generated from different stereo pairs. Finally, we applied an occupancy grids based integration algorithm to remove duplicated points to create an integrated point cloud. The experiments were performed using UAV images, and our experiments show that it is possible to remove gaps and duplicate points between point clouds generated from different stereo pairs.

• Journal of the Korean Society of Visualization
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• v.1 no.2
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• pp.58-70
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• 2003

Meteorological data contains observation and numerical weather prediction model output data. The computerized analysis and visualization of meteorological data often requires very high computing capability due to the large size and complex structure of the data. Because the meteorological data is frequently formed in multi-variables, 3-dimensional and time-series form, it is very important to visualize and analyze the data in 3D spatial domain in order to get more understanding about the meteorological phenomena. In this research, we developed interactive 3-dimensional visualization techniques for visualizing meteorological data on a PC environment such as volume rendering, iso-surface rendering or stream line. The visualization techniques developed in this research are expected to be effectively used as basic technologies not only for deeper understanding and more exact prediction about meteorological environments but also for scientific and spatial data visualization research in any field from which three dimensional data comes out such as oceanography, earth science, and aeronautical engineering.

• Proceedings of the Korean Vacuum Society Conference
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• 1997.07a
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• pp.173-176
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• 1997

A numerical analysis of the micro-discharge in an AC pplasma dispplay cell has been made using time-deppendent, 2-dimensional multi-fluid equations to understand the discharge pphysics of He-Xe discharge. The time deppendent distribution of the electron tempperature, densities of electrons, various ions and excited sppecies, and the effects fo the wall charge accumulated on the dielectric surface are obtained and comppared with the results of direct observation of time deppendent behavior of VUV and visible sppectra from single discharge cell observed using a gated, image intensified CCD to elucidate the discharge physics.

• Journal of Korean Society for Quality Management
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• v.42 no.2
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• pp.131-143
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• 2014

Purpose: This paper discusses the intrinsic assumption of one-dimensional relationship between the upper and lower levels in AHP(Analytic Hierarchy Process) for the Preliminary Feasibility Study of National R&D Program. This assumptions has not been questioned in academia and industry so far. Methods: This discussion is induced by understanding the Theory of Attractive Quality (Kano et al. 1984) and explains the limitation of AHP in the preliminary feasibility study of national R&D program. Results: In this paper, we propose a new questioning method based on two dimensional perspective, which is named as 2D-AHP (two dimensional AHP), to overcome the limitation. The main idea stems from the observation that the relationship between the upper and lower levels in AHP can vary depending on the subject of R&D. Conclusion: The two dimensional perspective pointed out in this paper should be more deeply studied in the field of MCDM(multi-criteria decision making) since it can be applied to the more general problems in human decision making.

• The Bulletin of The Korean Astronomical Society
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• v.43 no.1
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• pp.53.3-54
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• 2018

Solar Proton Events (SPEs) are the energetic phenomena related particle acceleration occurred in solar corona. Conventionally, they have been classified into two groups as the impulsive and gradual cases caused by reconnection in the flaring site and by shock generated by CME, respectively. In the previous studies, we classified these into four groups by analyzing the proton acceleration patterns in multi-energy channel observation. This showed that acceleration due to the magnetic reconnection may occur in the corona region relatively higher than the flaring site. In this study, we analyzes 54 SPEs observed in the energy band over 25 MeV from 2009 to 2013, where STEREO observations as well as SOHO can be utilized. From the multi-positional observation, we determine the exact time at which the Sun-Earth magnetic field line meets the CME shock structure by considering 3-dimensional structure of CME. Also, we determine the path length by considering the solar wind velocity for each event, so that the SPE onset time near the sun is obtained more accurately. Based on this study, we can get a more understanding of the correlation between CME progression and proton acceleration in the solar coronal region.