• 한국우주과학회:학술대회논문집(한국우주과학회보)
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• 한국우주과학회 2008년도 한국우주과학회보 제17권2호
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• pp.31.2-31.2
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• 2008

We present the results offar ultraviolet (FUV, 1350-1750 ${\AA}$) auroral observations made by the Far-ultraviolet IMaging Spectrograph (FIMS) instrument on the Korean microsatellite STSAT-1. The instrument was capable of resolving spatial structures of a few kilometers with the spectral resolution of 2-3 ${\AA}$. The observations were carried out simultaneously with the measurement of precipitating electrons using an electrostatic analyzer (ESA, 100 eV-20 keV) and a solid state telescope (SST, 170 keV-360 keV) on board the same satellite. With a careful mapping of the field lines, we were able to correlate the particle spectrum to the corresponding FUV spectrum of the footprints of the FIMS image that varied significantly in fine scales. We divided the FIMS spectral band into the LBH long (LBHL, 1640-1715 ${\AA}$) and LBH short (LBHS, 1380-1455 ${\AA}$) bands, and compared the electron energies with the intensities of LBHL and LBHS for the well-defined inverted-V structures. The result shows a strong correlation between the total LBH intensity and the energy flux measured by ESAwhile the peak energy itself does not correlate well with the LBH intensity. On the other hand, it was observed that the ratio of the LBHL intensity to that of LBHS increased significantly as the peak electron energy increased, primarily due to a smaller absorption by O2 at LBHL than at LBHS.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2007년도 춘계종합학술대회
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• pp.275-278
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• 2007

이 논문에서는 곤충의 발자국을 인식하기 위한 전 단계로서 인식대상이 되는 의미 있는 단위의 발자국 영역을 자동 추출하고자 한다. 인식의 대상이 되는 곤충들은 크기와 종류에 따라 남겨지는 발자국 패턴의 크기 및 간격이 다르게 나타난다. 따라서 이 논문에서는 패턴의 크기와 간격에 관계 없이 인식의 기본 단위가 되는 영역을 추출할 수 있도록 하기위해 개선된 군집화 알고리듬을 제안하였다. 제안한 알고리듬에서는 군집화를 위한 임계값이 군집화의 대상이 되는 모든 패턴들의 거리를 축적한 그래프의 형태에 따라 자동으로 설정되도록 하였다. 이러한 제안된 기법으로 군집화 된 영역은 의미 있는 주변 정보에 의해 곤충 인식에 기본 단계의 세그먼트를 자동 추출하게 된다.

• 한국지구과학회지
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• 제27권5호
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• pp.579-584
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• 2006

제주도의 후기 플라이스토세 퇴적층에서 깃털 화석을 발견하여 기재하였다. 수심이 얕은 바닷가에서 퇴적된 이 퇴적층에서는 사람 발자국을 포함하여 다양한 새 발자국 화석과 포유류 발자국 화석이 풍부하게 산출되었다. 담회색 이암에 밝은 색의 얇은 막으로 잘 보존된 깃털 화석은 깃 판(vane)이 있는 깃털의 일부분이다. 비록 표본의 크기가 길이 10.3 mm, 폭 9.0 mm로 비교적 작지만, 깃대 양쪽에 두 개의 편평한 깃판(vane), 거의 나란하게 휘어진 깃 가지(barbs)그리고 수많은 전면과 후면의 작은 깃 가지(barbules)들이 잘 보존되어 있다. 이 깃털 화석은 국내에서 최초로 발견되어 기재된 것이며 또한 전 세계의 플라이스토세 퇴적층에서도 처음으로 발견된 것이다.

• Journal of Communications and Networks
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• 제8권4호
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• pp.451-460
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• 2006

Since low earth orbit (LEO) satellite constellations have important advantages over geosynchronous earth orbit (GEO) systems such as low propagation delay, low power requirements, and more efficient spectrum allocation due to frequency reuse between satellites and spotbeams, they are considered to be used to complement the existing terrestrial fixed and wireless networks in the evolving global mobile network. However, one of the major problems with LEO satellites is their higher speed relative to the terrestrial mobile terminals, which move at lower speeds but at more random directions. Therefore, handover management in LEO satellite networks becomes a very challenging task for supporting global mobile communication. Efficient and accurate methods are needed for LEO satellite handovers between the moving footprints. In this paper, we propose a new seamless handover management scheme for LEO satellites (SeaHO-LEO), which utilizes the handover management schemes aiming at decreasing latency, data loss, and handover blocking probability. We also present another interesting handover management model called satellite mobility pattern based handover management in LEO satellites (PatHO-LEO) which takes mobility pattern of both satellites and mobile terminals into account to minimize the handover messaging traffic. This is achieved by the newly introduced billboard manager which is used for location updates of mobile users and satellites. The billboard manager makes the proposed handover model much more flexible and easier than the current solutions, since it is a central server and supports the management of the whole system. To show the performance of the proposed algorithms, we run an extensive set of simulations both for the proposed algorithms and well known handover management methods as a baseline model. The simulation results show that the proposed algorithms are very promising for seamless handover in LEO satellites.

• 천문학회지
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• 제38권4호
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• pp.471-478
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• 2005

Spectroscopic data obtained by the Infrared Interferometer Spectrometer (IRIS) aboard Voyager 1 and 2 have been re-visited. Using the spectroscopic data and footprints of the IRIS aperture on the planet, we constructed images of the stratosphere of Jupiter at the emission bands of hydrocarbons including $CH_4,\;C_2H_6,\;C_2H_2,\;C_3H_4,\;C_6H_6$, and $C_2H_4$. Thermal emission from the hydrocarbons on Jupiter originates from a broad region of the stratosphere extending from 1 to 10 millibars. We averaged the data using a bin of 20 degrees of longitude and latitudes in order to increase signal-to-noise ratios. The resultant images show interesting wave structure in Jupiter's stratosphere. Fourier transform analyses of these images yield wavenumbers 5 - 7 at mid-Northern and mid-Southern latitudes, and these results are different from those resulted from previous ground-based observations and recent Cassini CIRS, suggesting temporal variations on the stratospheric infrared pattern. The comparisons of the Voyager 1 and 2 spectra also show evidence of temporal intensity variations not only on the infrared hydrocarbon polar brightenings of hydrocarbon emissions but also on the stratospheric infrared structure in the temperate regions of Jupiter over the 4 month period between the two Voyager encounters. Short running title: Stratospheric Images of Jupiter derived from Voyager IRIS Spectra.

• 지구물리와물리탐사
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• 제21권1호
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• pp.41-53
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• 2018

전통적인 탄성파 탐사 자료처리 분야에서 겹반사파(multiple)는 잡음으로 취급되어 제거한 후 자료처리를 수행한다. 그러나 최근 겹반사파를 잡음이 아닌 하나의 신호로 인식하고 이를 영상화에 이용하는 연구가 많이 이루어지고 있다. 겹반사파는 일차 반사파(primary reflection)가 도달하지 못하는 지점까지 도달할 수 있어 적은 수의 송신원과 수신기로도 더 넓은 범위를 영상화 할 수 있다. 이를 검증하기 위해 본 연구에서는 영상화 기법 중 하나인 거꿀시간 참반사 보정(reverse-time migration)을 이용하여 겹반사파 자료를 영상화한 후 일차 반사파를 사용한 전통적인 거꿀시간 참반사 보정 결과와 비교하였다. 겹반사파를 독립적으로 사용하기 위해 자유면 기인 겹반사파 제거(surface-related multiple elimination; SRME)기법을 사용해 탄성파 자료에서 겹반사파를 분리하였다. 수치 예제를 통해 겹반사파를 이용한 참반사 보정 결과가 일차 반사파를 이용한 전통적인 참반사 보정 결과보다 더 넓은 범위를 영상화 할 수 있음을 확인하였고, 특히 천부 지층에서 두드러진 효과가 나타나는 것을 알 수 있었다. 또한 겹반사파를 이용한 참반사 보정은 자료취득 흔적(acquisition footprint)에 의한 영상 왜곡이 제거됨을 확인할 수 있었다.

• Journal of Plant Biotechnology
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• 제46권4호
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• pp.255-273
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• 2019

Orchids are indispensable to the floriculture industry due to their unique floral organization. The flowers have two outer whorls of tepals including a lip (labellum), and two inner whorls, pollinia and gynostemiun (column). The floral organization and development is controlled at the molecular level, mainly by the MADS-box gene family, comprising homeotic genes divided into type I and type II groups. The type I group has four sub-groups, Mα, Mβ, Mγ, and Mδ, playing roles in seed, embryo, and female reproductive organ development; the type II group genes form classes A, B, C, D, and E, which are a part of the MIKC^C subgroup with specific roles in florigenesis and organization. The coordinated functioning of these classes regulates the development of various floral whorls. The availability of genome and transcriptome sequence data for Phalaenopsis equestris offers an opportunity to validate the ABCDE model of flower development. Hence, this study sought to characterize the MADS-box gene family and elucidate of the ABCDE model. A total of 48 identified MADS-box proteins, including 20 type I [Mα (12), Mγ (8)] and 28 type II [MIKC^C (27), MIKC*(1)] members, were characterized for physico-chemical features and domains and motifs organization. The exon-intron distribution and the upstream cis-regulatory elements in the promoter regions of MADS-box genes were also analysed. The discrete pace of duplication events in type I and type II genes suggested differential evolutionary constraints between groups. The correlation of spatio-temporal expression pattern with the presence of specific cis-regulatory elements and putative protein-protein interaction within the different classes of MADS-box gene family endorse the ABCDE model of floral development.

• 한국통신학회논문지
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• 제41권5호
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• pp.602-609
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• 2016

현재와 같은 스마트 사회에서 정치인들은 자신들에게 보다 유리한 정치적 입지 구축을 위해 유권자들에 대해 각 종 빅 데이터를 분석하고 있다. 다시 말해 유권자들이 SNS나 인터넷 등에 올린 다양한 디지털 흔적들을 분석하여 이를 선거 전략이나 정치적 방향을 설정하는데 사용하고 있다. 이에 비해 역으로 유권자들은 정치인들이 어떤 의도를 가지고 정치 행위를 행하는지에 대한 정보를 추출해 내는 것이 어려운 실정이다. 따라서 유권자들도 정치인들이 의도하는 바가 무엇인지를 분석해 내는 것이 중요한 일이며, 이를 통해 상호 양방향의 소통이 행해지도록 해야만 한다. 이를 위해 본 논문에서는 정치인들이 말하는 음성을 분석하여 이들이 어떤 화법을 구사하여 그에 따른 상대적인 이익을 추구하고자 하는지 그 의도에 대한 규명 작업을 IT 기술을 적용하여 수행하고자 한다. 실험은 우선적으로 차기 대선에서 출마자로 거론되는 유력 정치인들에 대한 음성 분석을 통해 이들의 화법이 추구하는 음성이 다른 경쟁자들에 비해 상대적인 유리함이 무엇인지에 대한 규명 작업을 행하고자 한다.

• 한국의류학회지
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• 제16권4호
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• pp.485-493
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• 1992

Three kinds of tight skirts, slim type, straight type, and semi-tight type were investigated to obtain necessary information about the size of the back slit. Fourteen college students put on these experimental clothes and walked on the flat floor, going up and down the stairs. The dimensions of the back slit were measured by width and length. The stride length was taken from the record of footprints of walking. The correlation between the body measurement, stride length and the size of the back slit was studied. As a result of this experiment, the findings are as follows: 1. The size of the back slits differed from each skirt type at the level of p<0.001. In the case of walking on the floor, the average dimension of the back slit was 14.0 cm long 5.0 cm wide for the slim type,9.5 cm long 2.8 cm wide for the straight type and 2.1 cm long 0.5 cm wide for the semi-tight type. 2. In the case of walking on the stairways, the average dimension of the back slit was 16.0 cm long 5.8 cm wide for the slim type, 12.4 cm long 3.9 cm wide for the straight type and 3.1 cm long 1.1 cm wide for the semi-tight type. 3. The correlation between the height (stature, waist height, knee height) and the size of back slit was 0.3 to 0.6. The correlation between the girth (waist, hip) and the size of back slit was 0.3 to -0.5. 4. The correlation between the stride length and the size of back slit was 0.76 for the slim skirt, 0.56 for the straight skirt, 0.28 for the semitight skirt.

• 한국측량학회지
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• 제25권6_1호
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• pp.507-516
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• 2007

Segmentation and organization of the LiDAR (Light Detection and Ranging) data of the Earth's surface are difficult tasks because the captured LiDAR data are composed of irregularly distributed point clouds with lack of semantic information. The reason for this difficulty in processing LiDAR data is that the data provide huge amount of the spatial coordinates without topological and/or relational information among the points. This study introduces LiDAR data segmentation technique by utilizing histograms of the LiDAR height image data and analyzing roof shape for 3D reconstruction and visualization of the buildings. One of the advantages in utilizing LiDAR height image data is no registration required because the LiDAR data are geo-referenced and ortho-projected data. In consequence, measurements on the image provide absolute reference coordinates. The LiDAR image allows measurement of the initial building boundaries to estimate locations of the side walls and to form the planar surfaces which represent approximate building footprints. LiDAR points close to each side wall were grouped together then the least-square planar surface fitting with the segmented point clouds was performed to determine precise location of each wall of an building. Finally, roof shape analysis was performed by accumulated slopes along the profiles of the roof top. However, simulated LiDAR data were used for analyzing roof shape because buildings with various shapes of the roof do not exist in the test area. The proposed approach has been tested on the heavily built-up urban residential area. 3D digital vector map produced by digitizing complied aerial photographs was used to evaluate accuracy of the results. Experimental results show efficiency of the proposed methodology for 3D building reconstruction and large scale digital mapping especially for the urban area.