• Title/Summary/Keyword: Cluster Center

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Near-Infrared Imaging Spectrometer onboard NEXTSat-1

  • Jeong, Woong-Seob;Lee, Dae Hee;Moon, Bongkon;Park, Kwijong;Park, Sung-Joon;Pyo, Jeonghyun;Park, Youngsik;Kim, Il-Joong;Park, Won-Kee;Kim, Mingyu;Lee, Duk-Hang;Nam, Ukwon;Han, Wonyong;Im, Myungshin;Lee, Hyung Mok;Lee, Jeong-Eun;Shin, Goo-Hwan;Chae, Jangsoo
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.1
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    • pp.70.1-70.1
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    • 2013
  • New space program for "Next-Generation Small Satellite (NEXTSat)" launched last year after the success of the series of Science & Technology Satellite (STSAT). KASI proposed the near-infrared imaging spectrometer as a scientific payload onboard NEXTSat-1. It was selected as one of two scientific payloads. The approved scientific payload is the near-infrared imaging spectrometer for the study of star formation history (NISS). The efficient near-infrared observation can be performed in space by evading the atmospheric emission as well as other thermal noise. The observation of cosmic near-infrared background enables us to reveal the early Universe in an indirect way through the measurement of absolute brightness and spatial fluctuation. The detection of near-infrared spectral lines in nearby galaxies, cluster of galaxies and star forming regions give us less biased information on the star formation. In addition, the NISS will be expected to demonstrate our technologies related to the development of the Korea's leading near-infrared instrument for the future large infrared telescope, SPICA.

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Sleep Habits and Insomnia-Associated Factors in Korean Adult Population: A Cross-sectional Survey of Three Rural Communities (한국 성인의 수면습관 및 불면증 관련 요인 : 3개 농촌지역주민을 대상으로 한 단시적 연구)

  • Jeong, Do-Un;Sohn, Chang-Ho;Sung, Joo-Hon;Chang, Song-Hun;Lee, Kun-Sei;Lee, Won-Jin;Shin, Hai-Rim;Lee, Bu-Ok;Cho, Soo-Hun
    • Sleep Medicine and Psychophysiology
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    • v.4 no.2
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    • pp.201-212
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    • 1997
  • Objectives: We attempted to study sleep habits and insomnia-associated factors in Korean rural adult population. Methods : In 1,441 adult subjects of three rural communities selected by cluster sampling, we administered an epidemiologic survey using questionnaire methods from July 14, 1996 to July 28, 1996. Results : 1) Mean sleep latency and mean time to sleep again after awakening during nocturnal sleep were longer in females than in males. Females suffered more frequently from insomnia symptom, awakening during nocturnal sleep. morning headache, dysphoric mood in the morning, and the feeling of 'not refreshed' on waking-up than males. 2) The older age group (defined as those older than 65 years) was found to have earlier bed-time, longer sleep latency, more frequent nocturia, longer time to sleep again after awakening during nocturnal sleep, and more frequent insomnia symptom. 3) The presence of insomnia symptom more than once a week was significantly associated with suffering from physical illness, being divorced-separated-widowed, frequently feeling depressed, nocturia, or low education level. 4) In multiple logistic regression analysis, old age, being female, low education level, frequently feeling depressed, and nocturia were independently associated with the presence of insomnia symptom more than once a week. Conclusion : We conclude that, in a Korean rural adult population, insomnia symptom increases with age and females usually suffer more from insomnia symptom than males. In addition, low education level, feeling depressed mood frequently, and nocturia are found to be significantly associated independently with the presence of insomnia symptom more than once a week.

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Promoting Technology Convergence in Industrial Clusters through Intellectual Property Service Center (산업클러스터 기술융합 활성화를 위한 효율적인 지식재산서비스 지원 방안 연구)

  • So, Byeong-Woo;Gong, Byeong-Yeong
    • Asia-Pacific Journal of Business Venturing and Entrepreneurship
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    • v.6 no.1
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    • pp.133-158
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    • 2011
  • In 2030s, as we enter in to the era of BT (Bio-Technology) market opening up, technologies in all areas such as IT, data analysis, IC and biochemistry are necessitated. New development in technology will be based on "Convergence", especially between IT and BT. In order to have synergy effects from the convergence, those related industries and universities should be physically inter-related in an appropriate location. Until 2009, 819 industrial clusters where many Korean industries and firms are concentrated have been constructed in Korea. They have had supports from various institutions and facilities. However, few systems designed to assist "intellectual property (IP) service" for technology convergence are found in Korea. Thus, by analyzing current problems and challenges of the Korean industrial clusters, this paper suggests a possible answer to maximize the synergy from technology convergence through organic cooperation among companies in industrial clusters. This paper finds that the Korean industrial clusters need to establish IP service supporting center while suggesting its function and concept on organization structure, and work flow, which help firms to develop IP strategies. In addition, the paper provides a direction for current IP system and policies implemented by the Korean government to be more effective to small-and-medium-sized companies located in the industrial clusters.

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Evaluation of leaf morphology for distinguishing Prunus (Rosaceae) from Jeju, Korea (제주도산 벚나무속 잎 형질의 분류학적 검토)

  • Kim, Chan-Soo;Moon, Myung-Ok;Cheong, Eun Ju;Byun, Gwang Ok
    • Korean Journal of Plant Taxonomy
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    • v.35 no.2
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    • pp.81-98
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    • 2005
  • Leaf morphology was examined for Prunus species from Jeju Island. Analyzed were the leaf blade length, petiole length, width of blade, number of veins and angle of the base to the mid-vein as quantitative characters and the distribution of trichome, position of glandsand leaf features qualitative characters. A total of 25 OTU were phenetically analyzed by UPGMA. The resuling phenograms slightly differ from the currently recognized taxonomic system in two points. Prunus mume was clustered with P. padus and P. buergeriana. Prunu spendula and P. yedoensis were separated from the cluster of P. jaamasakura, P. speciosa, P. sargentii and P. jamasakura var. quelpaertensis. Except for the members of subgenus Cerasus, subgenera Padus (P. buergeriana and P. padus), Microcerasus (P. japonica) and Amygdalus were well defined. Some morphological characters of leaves such as the ratio of blade length to width, the length of blade to petiole, number of veins, the distance between the gland and base, the angle of base to mid-vein, and the distribution of trichome were useful as diagnostic features for Prunus from Jeju Island.

Phylogeny of Ganoderma Based on the Restriction Enzyme Analysis of Mitochondrial DNA (미토콘드리아 DNA의 제한효소 분석법에 의한 영지의 계통분류)

  • Hong, Soon-Gyu;Jung, Hack-Sung
    • Korean Journal of Microbiology
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    • v.32 no.4
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    • pp.245-251
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    • 1994
  • Ten strains of 7 species from the genus Ganoderma, G. lucidum ATCC 64251, FP-103561-T, and ES70701, G. applanatum ATCC 44053 and FP-57035-T. G. lobatum ATCC 42985, G. resinaceum ATCC 52416, G. subamboinense var. laevisporum ATCC 52420, G. meredithae ATCC 64492, and G. microsporum ATCC 76024, were studied to discuss their phylogenetic relationships by utilizing restriction fragment length polymorphisms (RFLPs) of mitochondrial DNAs (mtDNAs). Six restriction enzymes, BamHI, BglII, EcoRI, HindIII, PvuII, and XbaI which digested mtDNAs into adequate numbers of restriction fragments for cluster analysis, were used in this study. Restriction profiles of strains for each restriction enzyme were treated as analysis characters to calculate similarity coefficients, which were converted into nucleotide sequence divergence values whose mean values were then arranged in a matrix table. This table was utilized for a phylogenetic analysis using the Neighborjoining method of the PHYLIP package to construct phylogenetic tree. Three strains of G. lucidum and two strains of G. applanatum exhibited different lineages each but one of G. applanatum strains showed a close relationship with G. lobatum, which reflected the species complexity of these species whose strains were phenotypically indistinguishable but genetically distinct. The present results suggest that the natural classification of Ganoderma needs to be considered from the viewpoints of molecular biology-based systematics as well as morphological classifications and cultural identifications for better phylogenetic conclusions.

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The Development of Dynamic Forecasting Model for Short Term Power Demand using Radial Basis Function Network (Radial Basis 함수를 이용한 동적 - 단기 전력수요예측 모형의 개발)

  • Min, Joon-Young;Cho, Hyung-Ki
    • The Transactions of the Korea Information Processing Society
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    • v.4 no.7
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    • pp.1749-1758
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    • 1997
  • This paper suggests the development of dynamic forecasting model for short-term power demand based on Radial Basis Function Network and Pal's GLVQ algorithm. Radial Basis Function methods are often compared with the backpropagation training, feed-forward network, which is the most widely used neural network paradigm. The Radial Basis Function Network is a single hidden layer feed-forward neural network. Each node of the hidden layer has a parameter vector called center. This center is determined by clustering algorithm. Theatments of classical approached to clustering methods include theories by Hartigan(K-means algorithm), Kohonen(Self Organized Feature Maps %3A SOFM and Learning Vector Quantization %3A LVQ model), Carpenter and Grossberg(ART-2 model). In this model, the first approach organizes the load pattern into two clusters by Pal's GLVQ clustering algorithm. The reason of using GLVQ algorithm in this model is that GLVQ algorithm can classify the patterns better than other algorithms. And the second approach forecasts hourly load patterns by radial basis function network which has been constructed two hidden nodes. These nodes are determined from the cluster centers of the GLVQ in first step. This model was applied to forecast the hourly loads on Mar. $4^{th},\;Jun.\;4^{th},\;Jul.\;4^{th},\;Sep.\;4^{th},\;Nov.\;4^{th},$ 1995, after having trained the data for the days from Mar. $1^{th}\;to\;3^{th},\;from\;Jun.\;1^{th}\;to\;3^{th},\;from\;Jul.\;1^{th}\;to\;3^{th},\;from\;Sep.\;1^{th}\;to\;3^{th},\;and\;from\;Nov.\;1^{th}\;to\;3^{th},$ 1995, respectively. In the experiments, the average absolute errors of one-hour ahead forecasts on utility actual data are shown to be 1.3795%.

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Crystal Structure of Xenon Encapsulate within Na-A Zeolite

  • Im, U Taek;Park, Man;Heo, Nam Ho
    • Bulletin of the Korean Chemical Society
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    • v.21 no.1
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    • pp.75-80
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    • 2000
  • The positions of Xe atoms encapsulated in the molecular-dimensioned cavities of fully dehydrated Na-A have been determined. Na-A was exposed to 1050atm of xenon gas at 400 $^{\circ}C$ for seven days, followed by cooling at pressure to encapsulate Xe atoms. The resulting crystal structure of Na-A(7Xe) (a = 12.249(1) $\AA$, $R_1$ = 0.065, and $R_2$ = 0.066) were determined by single-crystal X-ray diffraction techniques in the cubic space group Pm3m at 21(1) $^{\circ}C$ and 1 atm. In the crystal structure of Na-A(7Xe), seven Xe atoms per unit cell are distributed over four crystallographically distinct positions: one Xe atom at Xe(1) lies at the center of the sodalite unit, two Xe atoms at Xe(4) are found opposite four-rings in the large cavity, and four Xe atoms, two at Xe(2) and others at Xe(3), respectively, occupy positions opposite and between eight- and six-rings in the large cavity. Relatively strong interactions of Xe atoms at Xe(2) and Xe(3) with $Na^+$ ions of four-, eight-, and six-rings are observed:Na(1)-Xe(2) = 3.09(6), Na(2)-Xe(3) = 3.11(2), and Na(3)-Xe(2) = 3.37(8) $\AA$. In each sodalite unit, one Xe atom is located at its center. In each large cavity, six Xe atoms are found, forming a distorted octahedral arrangement with four Xe atoms, at equatorial positions (each two at Xe(2) and Xe(3)) and the other two at axial positions (at Xe(4)). With various reasonable distances and angles, the existence of $(Xe)_6$ cluster is proposed (Xe(2)-Xe(3) = 4.78(6) and 4.94(7), Xe(2)-Xe(4) = 4.71(6) and 5.06(6), Xe(3)-Xe(4) = 4.11(3) and 5.32(4) $\AA$, Xe(2)-Xe(3)-Xe(2) = 93(1), Xe(3)-Xe(2)-Xe(3) = 87(1), Xe(2)-Xe(4)-Xe(2) = 91(4), Xe(2)-Xe(4)-Xe(3) = 55(2), 59(1), 61(1), and 68(1), and Xe(3)-Xe(4)-Xe(3) = 89($^{\circ}1$)). These arrangements of the encapsulated Xe atoms in the large cavity are stabilized by alternating dipoles induced on Xe(2), Xe(3), and Xe(4) by eight- and six-ring $Na^+$ ions as well as four-ring oxygens, respectively.

Analysis on the Key Factors of Entrepreneurship Education for Public Technology Commercialization : Focusing on the Performance of Korean I-Corps Project (공공기술 사업화를 위한 창업교육의 핵심요인 분석 : 한국형 아이코어 사업성과를 중심으로)

  • Lee, Won-Cheul;Choi, Jong-In;Choi, Tae-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.22 no.1
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    • pp.159-170
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    • 2021
  • As the main purpose of R&D changes from the center of knowledge creation to the center of economic value creation through technology transfer and commercialization, public technologies can also secure economic feasibility as well as make a social contribution. Korea has been focusing on fostering core human resources who can lead the commercialization of basic and original research results by launching the 'Support project for exploring startups linked with public technology-based markets' since 2015 in order to promote public technology startup. This study is based on the results of a survey for the purpose of analyzing the performance of this project. In addition, this study derived four factors related to the I-corps project performance from the results of this survey and verified the relationship between these factors through structural equation model analysis. In summary, it was confirmed that 'Application Level' and 'Business Model,' which are positively affected directly from 'Entrepreneurship Learning,' have positive effects on 'Financial Resources'. Furthermore, the indirect effect of 'Entrepreneurship Learning' on 'Financial Resources' was verified. In particular, the high level of impact of 'Entrepreneurship Learning' on 'Application Level,' and the impact of 'Application Level' on 'Business Model' and 'Financial Resources' were also positive.

Comparing the Service Coverages of Subways and Buses and Estimating the Walking Distances of Their Users (지하철과 버스의 서비스권역 비교 및 이용자들의 도보거리 추정 - 부산시를 중심으로 -)

  • Kim, Kyung Whan;Lee, Deok Hwan;Choi, Jong Moon;Oh, Il Sung
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.30 no.6D
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    • pp.541-552
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    • 2010
  • The light rail transit (LRT) having bus lines as subsystem is being constructed or planned in the suburban area of metropolitans and medium size cities. However, there is difficulty in establishing the service coverage (SC) of the LRT because the LRT is a completely new transit mode in Korea. The purpose of this study is to provide the basic data and techniques to be used for establishing the SC of the future LRT by understanding the SC characteristics of buses and subways and building models to estimate the walking distances of their users. Busan City is selected as the study city and the SC's of buses and subways are surveyed simultaneously. A total of 9 variables for 82 stations are collected and the cluster analysis is conducted about the variables. The station areas are divided to three types of CBD (Central Business District), sub-CBD and regional center based on the analysis. A station in each area is selected as the study station. At the walking distance (WD) analysis for each mode, the 80 percentile WD of the subway is 672 m and that of the bus is 472 m. In comparing the SC's of both modes by the type of station areas, there are not significant differences between the SC's of sub-CBD and regional center except CBD. At analysis of the relationship between the personal attributes and the WD, for subway users the WD of female is longer than that of male and apartment residents use subway more positively than single house residents do. For the models to estimate the walking distances, the simple regression models were built employing the income as independent variable by dividing the stations into CBD abd non-CBD stations.

A Study on Policy Trends and Location Pattern Changes in Smart Green-Related Industries (스마트그린 관련 산업의 정책동향과 입지패턴 변화 연구)

  • Young Sun Lee;Sun Bae Kim
    • Journal of the Economic Geographical Society of Korea
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    • v.27 no.1
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    • pp.38-52
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    • 2024
  • Digital transformation industry contributes to the improvement of productivity in overall industrial production, the smart green industry for carbon neutrality and sustainable growth is growing as a future industry. The purpose of this paper is to explore the status and role of the industry in the future industry innovation ecosystem through the analysis of the growth drivers and location pattern changes of the smart green industry. The industry is on the rise in both metropolitan and non-metropolitan areas, and the growth of the industry can be seen in non-metropolitan and non-urban areas. In particular, due to the smart green industrial complex pilot project, the creation of Gwangju Jeonnam Innovation City, and the promotion of new and renewable energy policies, the emergence of core aggregation areas (HH type) in the coastal areas of Honam and Chungcheongnam-do, and the formation of isolated centers (HL type) in the Gyeongsang region, new and renewable energy production companies are being accumulated in non-metropolitan areas. Therefore, the smart green industry is expected to promote the formation of various specialized spokes in non-urban areas in the future industrial innovation ecosystem that forms a multipolar hub-spoke network structure, where policy factors are the triggers for growth.