• Title/Summary/Keyword: Cluster observation

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Induction of Shoot Primordium in Culture of Garlic (Allium sativum L.) (마늘 배양에 있어서 신초원기 유도)

  • Choi Joo-Soo;Lee Bok-Kyu;Huh Man-Kyu
    • Journal of Life Science
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    • v.16 no.3 s.76
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    • pp.459-463
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    • 2006
  • Cultivated garlic, Allium sativum L. is economically important for leaves and bulbs, which historically were used in Korea for spices and condiments of Korean food as well as medicine crops. This experiment was carried out to investigate the effect of development and differentiation on culture of A. sativum (cv: white 6) by explant position, hormone composition and sucrose concentration in culture media. Culture method was investigated to induce shoot primordium. Culture efficiency was better with lower tissue of foliage leaf in explant position and on the medium with NAA 0.02 + BAP 1.0 mg/l in hormone composition than any other. Precocious shoot and callus were induced from shoot apex. Shoot was efficiently differentiated on 4,000 mg/l sucrose with increasing concentration of BAP. Shoot primordium was also induced with liquid rotary culture by histological observation. Rhizoid was induced from callus tissue cluster on medium with NAA 0.02 + BAP 2.0 mg/l.

Camera for Quasars in Early Universe

  • Park, Won-Kee;Pak, Soojong;Im, Myungshin;Choi, Changsu;Jeon, Yiseul;Chang, Seunghyuk;Jeong, Hyeonju;Lim, Juhee;Kim, Eunbin;Choi, Nahyun;Lee, Hye-In;Kim, Sanghyuk;Jeong, Byeongjoon;Ji, Taegeun
    • The Bulletin of The Korean Astronomical Society
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    • v.38 no.2
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    • pp.68.2-68.2
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    • 2013
  • Camera for QUasars in EArly uNiverse (CQUEAN) is an optical CCD camera system made by Center for Exploration of the Origin of the Universe (CEOU). CQUEAN is developed for follow-up observation of red sources such as high-redshift quasar candidates ($z{\geq}5$), gamma-ray bursts (GRB), brown dwarfs and young stellar objects. The CQUEAN is composed of a science camera with deep-depletion CCD chip which is sensitive at around $1{\mu}m$, a set of custom-made wide-band filters for detection of quasar candidates at z~5, and a guide camera. A focal reducer was developed to secure $4.8^{\prime}{\times}4.8^{\prime}$ field of view, and an in-house user software for efficient data acquisition. CQUEAN was attached to 2.1m Otto Struve Telescope in McDonald Observatory, USA, in August 2010. About 1000 quasar candidates including 3 confirmed with follow-up spectroscopy, have been observed so far, and many high-z galaxy cluster candidates, GRBs and supernovae were also observed. And monitoring of HBC 722, a young stellar object, is under way since 2011. Further enhancement of CQUEAN including the introduction of narrow-band filters is planned.

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Study on Risk Reduction Behavior According to Participation Motivation of Mountain Climbing Activity and Level of Risk Perception (등산 활동 참여동기와 위험지각 수준에 따른 위험감소행동 연구)

  • Bang, Gi Seong;Yoo, Shin Jung
    • Fashion & Textile Research Journal
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    • v.15 no.4
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    • pp.523-532
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    • 2013
  • This study investigates risk reduction behavior with risk perception in outdoor wear purchase situations. Data were collected via a questionnaire from 400 consumers between the ages of 20 to 50 residing in Seoul and Kyonggi-do. Data analysis were conducted with SPSS 20 program on the reliability test, factor analysis, cluster analysis, t-test, ANOVA, and Duncan's multiple range test. Factor analyses were employed for the participation motivation of mountain climbing activities, risk reduction behavior and risk perception. Five factors were for the participation motivation of mountain climbing activities (health and fitness, external ostentation, achievement and excitement, improvement of climbing skills, and society). Five factors were for risk perception (fashionability loss and social risk, time and convenience loss, economic risk, performance risk, and psychological risk). Five factors were for the risk reduction behavior (interpersonal information sources use, marketer-dominated information sources use, professional information sources use, pre-purchase deliberation/observation/experience, and brand dependence). Three clusters were identified based on the motivation of outdoor activities (the affiliation/display, the health/internal informativeness and low motivation). The participation motivation for mountain climbing activities were varied. Manufacturers should increase efforts to develop products with good qualities at a reasonable cost as well as establish new marketing strategies since the risk of product performance and economic efficiency in the purchase of outdoor wear was a significant consumer perception.

Iterative LBG Clustering for SIMO Channel Identification

  • Daneshgaran, Fred;Laddomada, Massimiliano
    • Journal of Communications and Networks
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    • v.5 no.2
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    • pp.157-166
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    • 2003
  • This paper deals with the problem of channel identification for Single Input Multiple Output (SIMO) slow fading channels using clustering algorithms. Due to the intrinsic memory of the discrete-time model of the channel, over short observation periods, the received data vectors of the SIMO model are spread in clusters because of the AWGN noise. Each cluster is practically centered around the ideal channel output labels without noise and the noisy received vectors are distributed according to a multivariate Gaussian distribution. Starting from the Markov SIMO channel model, simultaneous maximum ikelihood estimation of the input vector and the channel coefficients reduce to one of obtaining the values of this pair that minimizes the sum of the Euclidean norms between the received and the estimated output vectors. Viterbi algorithm can be used for this purpose provided the trellis diagram of the Markov model can be labeled with the noiseless channel outputs. The problem of identification of the ideal channel outputs, which is the focus of this paper, is then equivalent to designing a Vector Quantizer (VQ) from a training set corresponding to the observed noisy channel outputs. The Linde-Buzo-Gray (LBG)-type clustering algorithms [1] could be used to obtain the noiseless channel output labels from the noisy received vectors. One problem with the use of such algorithms for blind time-varying channel identification is the codebook initialization. This paper looks at two critical issues with regards to the use of VQ for channel identification. The first has to deal with the applicability of this technique in general; we present theoretical results for the conditions under which the technique may be applicable. The second aims at overcoming the codebook initialization problem by proposing a novel approach which attempts to make the first phase of the channel estimation faster than the classical codebook initialization methods. Sample simulation results are provided confirming the effectiveness of the proposed initialization technique.

The annihilation of the flow pattern defects in CZ-silicon crystal by high temperature heat treatment (고온 열처리에 의한 결정결함의 재용해)

  • 서지욱;김영관
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.11 no.3
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    • pp.89-95
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    • 2001
  • The CZ-silicon crystal was annealed at $1350^{\circ}C$ to dissolve the vacancy type grown-in defects. A this temperature, the equilibrium concentration of the oxygen in the silicon crystal is around $1.7{\times}10^{18}$ which induces the oxygen undersaturation in the silicon crystal. This situation results in the faster dissolution of the grown-in defects in the bulk of the silicon wafer than near the surface. This indicates the possibility that the presence of the higher concentration of silicon interstitial hinders the dissolution of the grown-in defects, which were known to compose of the vacancy clusters with surrounding silicon oxide film. This expectation was confirmed by the observation that the slower dissolution of the grown-in defects near the surface of the silicon wafer in the oxygen atmosphere than in the argon atmosphere. This result is quite opposite to the previous argument hat presence of the excess silicon interstitial leads to faster dissolution of the vacancy type defects.

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Multi-platform Visualization System for Earth Environment Data (지구환경 데이터를 위한 멀티플랫폼 가시화 시스템)

  • Jeong, Seokcheol;Jung, Seowon;Kim, Jongyong;Park, Sanghun
    • Journal of the Korea Computer Graphics Society
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    • v.21 no.3
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    • pp.36-45
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    • 2015
  • It is important subject of research in engineering and natural science field that creating continuing high-definition image from very large volume data. The necessity of software that helps analyze useful information in data has improved by effectively showing visual image information of high resolution data with visualization technique. In this paper, we designed multi-platform visualization system based on client-server to analyze and express earth environment data effectively constructed with observation and prediction. The visualization server comprised of cluster transfers data to clients through parallel/distributed computing, and the client is developed to be operated in various platform and visualize data. In addition, we aim user-friendly program through multi-touch, sensor and have made realistic simulation image with image-based lighting technique.

Evaluation of Fruit Quality and the Anatomical Characteristics of Gaeryangmeoru (Vitis sp.) Grapes Depending on the Growth Stage (개량머루(Vitis sp.)의 생육기에 따른 과실 품질 및 형태학적 관찰)

  • Kwon, YongHee
    • Journal of Bio-Environment Control
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    • v.23 no.2
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    • pp.65-70
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    • 2014
  • The aim of this study was to identify the chronological growth characteristics of Gaeryangmeoru grapes, by observation of the developmental process of the axillary bud, fruit quality, and anatomical structure of the pericarp. No necrosis of axillary buds was observed, irrespective of node position of the shoot, from shoot occurrence to leaf fall. Berry weight, cluster weight, soluble solid content and titratable acidity were analyzed to be 1.2 g, 128.8 g, $16.9^{\circ}Brix$, and 1.57%, respectively, at maturity. The sugar was composed of fructose and glucose, with a ratio of 1:1 (fructose: glucose) at maturity. Malic acid was predominant among the organic acids, and conformed to the changes of chronological titratable acidity. Sugar and organic acid content changed dramatically starting a week before veraison. The degraded ovules were observed before and after fertilization, and the pericarp was composed of one epidermis, and seven to ten hypodermis layers at maturity.

A Study on the Landscape Design of the Cheongsong Apple Theme Park (청송 사과체험테마파크 기본계획)

  • Kwon, Jin-Wook;Park, Chan-Yong
    • Journal of Korean Society of Rural Planning
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    • v.19 no.3
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    • pp.195-203
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    • 2013
  • This study aimed to plan a distinctive apple theme park, thereby specializing the nationwide brand of Cheongsong apple. Detailed objectives included: to establish the best possible environments in Korea to taste and appreciate apple and enjoy the Cheongsong Apple Festival; to identify and foster natural, cultural and social resources in the clean environment of Cheongsong; to clusterize research and production infrastructures for strengthening local competitiveness; and to develop a hub for the vitalization of the region where visitors and locals can mutually prosper. The study was multi-phased. The first stage included basic surveys such as local status and environment analysis and similar case studies, and the second stage was to review the appropriateness of theme selection, develop basic principles and strategies for development goals and review and incorporate project details. And the third stage aimed to develop a comprehensive plan from spatial plans and program plans and suggest plans to vitalize the operation of the park. The dimension of the subject site was $180,150m^2$, which was divided into four areas, in consideration of the land use and the environmental characteristics of the resources, for developing a land use scheme. The four areas were named: the apple-theme cultual area; the agricultural culture experience area; the plaza for exchange and harmony; and the plaza for natural observation. This study has significance in that it can serve as a case to develop farm theme parks, and as a case of appropriate development of programs to identify amenity resources with a focus on the existing resources and in consideration of local characteristics.

Survey of Globular Clusters with the AKARI FIS for the Intracluster Dusts

  • Pyo, Jeong-Hyun;Jeong, Woong-Seob;Kim, Eun-Hyeok;Lee, Myung-Gyoon;Hong, Seung-Soo
    • The Bulletin of The Korean Astronomical Society
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    • v.35 no.1
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    • pp.52.2-52.2
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    • 2010
  • In search of the intracluster dusts, we have made a survey of globular clusters (GCs) with the Far-Infrared Surveyor (FIS) aboard AKARI, the Japanese infrared space satellite. The GCs are thought to host dust particles that are condensed from the material injected by the cluster asymptotic giant branch (AGB) stars. However, attempts to detect dust emission from GCs had not been successful until a significant amount of far-infrared (FIR) emission was detected close to the NGC 7078 center by the ISO observations (Evans et al. 2003). Recent FIR observations by the AKARI (Matsunaga et al. 2008) and the Spitzer Space Telescope (Boyer et al. 2006; Barmpy et al. 2009) reported a tentative detection of the dusts in NGC 5024 and NGC 6341, and also confirmed the previous ISO dust detection from NGC 7078. We have observed 17 selected GCs in four FIS wavebands at 65, 90, 140, and 160 micrometers. Each observation covers about $10'{\times}10'$ area centered at each GC. The resulting images show extended structures and/or blobs around the GCs. The extended structures are very suggestive of the Galactic cirrus, while the blobs around NGC 288 and NGC 4833 seem to be related to the two clusters. In this presentation, we will report four representative cases of our survey results and discuss the properties of newly detected sources.

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Classification of Land Cover over the Korean Peninsula using MODIS Data (MODIS 자료를 이용한 한반도 지면피복 분류)

  • Kang, Jeon-Ho;Suh, Myoung-Seok;Kwak, Chong-Heum
    • Atmosphere
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    • v.19 no.2
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    • pp.169-182
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    • 2009
  • To improve the performance of climate and numerical models, concerns on the land-atmosphere schemes are steadily increased in recent years. For the realistic calculation of land-atmosphere interaction, a land surface information of high quality is strongly required. In this study, a new land cover map over the Korean peninsula was developed using MODIS (MODerate resolution Imaging Spectroradiometer) data. The seven phenological data set (maximum, minimum, amplitude, average, growing period, growing and shedding rate) derived from 15-day normalized difference vegetation index (NDVI) were used as a basic input data. The ISOData (Iterative Self-Organizing Data Analysis), a kind of unsupervised non-hierarchical clustering method, was applied to the seven phenological data set. After the clustering, assignment of land cover type to the each cluster was performed according to the phenological characteristics of each land cover defined by USGS (US. Geological Survey). Most of the Korean peninsula are occupied by deciduous broadleaf forest (46.5%), mixed forest (15.6%), and dryland crop (13%). Whereas, the dominant land cover types are very diverse in South-Korea: evergreen needleleaf forest (29.9%), mixed forest (26.6%), deciduous broadleaf forest (16.2%), irrigated crop (12.6%), and dryland crop (10.7%). The 38 in-situ observation data-base over South-Korea, Environment Geographic Information System and Google-earth are used in the validation of the new land cover map. In general, the new land cover map over the Korean peninsula seems to be better classified compared to the USGS land cover map, especially for the Savanna in the USGS land cover map.