• Title/Summary/Keyword: cluster method

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Novel Packet Switching for Green IP Networks

  • Jo, Seng-Kyoun;Kim, Young-Min;Lee, Hyun-Woo;Kangasharju, Jussi;Mulhauser, Max
    • ETRI Journal
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    • v.39 no.2
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    • pp.275-283
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    • 2017
  • A green technology for reducing energy consumption has become a critical factor in ICT industries. However, for the telecommunications sector in particular, most network elements are not usually optimized for power efficiency. Here, we propose a novel energy-efficient packet switching method for use in an IP network for reducing unnecessary energy consumption. As a green networking approach, we first classify the network nodes into either header or member nodes. The member nodes then put the routing-related module at layer 3 to sleep under the assumption that the layer in the OSI model can operate independently. The entire set of network nodes is then partitioned into clusters consisting of one header node and multiple member nodes. Then, only the header node in a cluster conducts IP routing and its member nodes conduct packet switching using a specially designed identifier, a tag. To investigate the impact of the proposed scheme, we conducted a number of simulations using well-known real network topologies and achieved a more energy- efficient performance than that achieved in previous studies.

A Study on Travel Activity and Shopping Behavior of 20's-30's Korean Overseas Travelers (20-30대 해외여행자의 여행활동과 쇼핑행동에 관한 연구)

  • Jeon, Yangjin
    • Human Ecology Research
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    • v.54 no.5
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    • pp.529-539
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    • 2016
  • This study confirmed shopping behavior of Korean young overseas tourists and its effect on travel evaluation. I first identified core factors of travel activity preference, travel shopping propensity, and shopping products. The effect of shopping product satisfaction on tour satisfaction and post-tour intention was then investigated. Based on travel activities, tourists were grouped, and their characteristics were compared. An online survey method was performed to obtain data of 20's-30's Korean unmarried people, while factor analysis, regression analysis, chi-square test, analysis of variance (ANOVA), and cluster analysis were applied to analyze data. The results were as follows. First, six travel activities (city life, art/shopping, cultural experience, entertainment, field experience, and friendship), three shopping propensity (novelty/uniqueness, utility, and prestige), and four product groups (fashion goods, household goods, crafts, and foods) were found by factor analyses. Second, travel activity tended to influence shopping propensity, which then influenced shopping products preference. All factors of travel activity seemed to affect the three travel shopping propensities. Third, shopping satisfaction was shown to affect tour satisfaction, and posttour behavior. Finally, four tourist groups (active, social, pleasure, and passive) differed in terms of preferred tour activities, shopping propensity, and tour behavior. Active tourists rated the highest scores and passive ones rated the lowest for most evaluations.

A Study on Purchase Behavior and Design Preference of Luxury Hand Bag Users aged 20 to 30 by Lifestyle and Age Variable (20-30대 명품 핸드백 소유자를 대상으로 라이프스타일과 연령에 따른 구매행동 및 디자인 선호도 분석)

  • Kim, Chil-Soon;Lee, Jin
    • Fashion & Textile Research Journal
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    • v.13 no.6
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    • pp.827-837
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    • 2011
  • The purpose of this study was to observe premium handbag users who are 20 to 30 year old of age, to determine purchase behavior and design preference of handbags by lifestyle and age variable to help market segmentation. A survey instrument was used. A sample was selected by quota sampling method from 20 to 30 aged Korean women, and reliable 538 data were analyzed by SPSS. Cluster type towards lifestyle and age were independent variable. There are two types of lifestyle clusters toward luxury handbags; Strongly favored and weakly favored group toward luxury handbags. Strongly favored group of luxury goods considered more brand, country of origin, and trend, while young people considered more new arrival of design in purchase of products. Preferred design type of hand bag was statistically associated with age variable. 20s consumers preferred shopper bag style and big size of handbags. Leather was preferred by the group of the strongly favored luxury goods. Through this research finding, we hope handbag brand market segmentation will be based on lifestyle and age variable to reflect customer's demand.

Inhibitory Effects of Norwogonin, Oroxylin A, and Mosloflavone on Enterovirus 71

  • Choi, Hwa Jung;Song, Hyuk-Hwan;Lee, Jae-Sug;Ko, Hyun-Jeong;Song, Jae-Hyoung
    • Biomolecules & Therapeutics
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    • v.24 no.5
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    • pp.552-558
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    • 2016
  • Severe complications associated with EV71 infections are a common cause of neonatal death. Lack of effective therapeutic agents for these infections underlines the importance of research for the development of new antiviral compounds. In the present study, the anti-EV71 activity of norwogonin, oroxylin A, and mosloflavone from Scutellaria baicalensis Georgi was evaluated using a cytopathic effect (CPE) reduction method, which demonstrated that all three compounds possessed strong anti-EV71 activity and decreased the formation of visible CPEs. Norwogonin, oroxylin A, and mosloflavone also inhibited virus replication during the initial stage of virus infection, and they inhibited viral VP2 protein expression, thereby inhibiting viral capsid protein synthesis. However, ribavirin has a relatively weaker efficacy compared to the other drugs. Therefore, these findings provide important information that will aid in the utilization of norwogonin, oroxylin A, and mosloflavone for EV71 treatment.

A Fundamental Study on the Development of a Variable Preload Device Using Toggle Joint Mechanism (토글 조인트장치를 이용한 가변예압장치 개발을 위한 기초 연구)

  • Choi, Chi Hyuk;Cha, Na Hyeon;Lee, Choon Man
    • Journal of the Korean Society for Precision Engineering
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    • v.30 no.3
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    • pp.260-265
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    • 2013
  • To increase the machine accuracy by improving the stiffness of spindle bearings, preload was applied to the spindle bearings. The methods of fixed position preload, convertible preload, constant pressure preload, and variable preload are used to apply the preload to the spindle bearing. The previous studies performed by the author of this study were variable preload methods using rubber pressure and centrifugal force based on mechanical systems. This study proposed a toggle joint mechanism that could be applied to variable preload method using centrifugal force and rubber pressure to increase the preload. Also, a finite element analysis was conducted to predict the deformation of the rubber and change of the preload. And the analysis results showed that the preload by the device using rubber pressure only was increased by the toggle joint mechanism using rubber pressure.

Geoacoustic Parameters Inversion Using Parallel Multi-Population Genetic Algorithm (병렬 다중 개체군 유전 알고리즘을 이용한 지음향 파라미터 역산)

  • Oh Taekhwan;Na Jungyul;Lee Seongwook;Kim Seongil;Park Joung-Soo
    • The Journal of the Acoustical Society of Korea
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    • v.24 no.6
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    • pp.309-316
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    • 2005
  • This paper Presents the geoacoustic inversion with Parallel Multi-Population Genetic Algorithm (PMPGA). This method is the modified form of simple genetic algorithm (SGA), which is devised for complementing the defects of simple genetic algorithm. The light bulb source and vertical line array (VLA) receiver are used for geoacoustic inversion. The results of this study show the geoacoustic Parameters can be estimated by PMPGA and the proposed algorithm is 1.7 times as fast as serial one on an average.

Communication-Power Overhead Reduction Method Using Template-Based Linear Approximation in Lightweight ECG Measurement Embedded Device (경량화된 심전도 측정 임베디드 장비에서 템플릿 기반 직선근사화를 이용한 통신오버헤드 감소 기법)

  • Lee, Seungmin;Park, Kil-Houm;Park, Daejin
    • IEMEK Journal of Embedded Systems and Applications
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    • v.15 no.5
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    • pp.205-214
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    • 2020
  • With the recent development of hardware and software technology, interest in the development of wearable devices is increasing. In particular, wearable devices require algorithms suitable for low-power and low-capacity embedded devices. Among them, there is an increasing demand for a signal compression algorithm that reduces communication overhead, in order to increase the efficiency of storage and transmission of electrocardiogram (ECG) signals requiring long-time measurement. Because normal beats occupy most of the signal with similar shapes, a high rate of signal compression is possible if normal beats are represented by a template. In this paper, we propose an algorithm for determining the normal beat template using the template cluster and Pearson similarity. Also, the template is expressed effectively as a few vertices through linear approximation algorithm. In experiment of Datum 234 of MIT-BIH arrhythmia database (MIT-BIH ADB) provided by Physionet, a compression ratio was 33.44:1, and an average distribution of root mean square error (RMSE) was 1.55%.

Analysis of Genetic Polymorphism Among Six Korean Wild Artemisia spp. by Using RAPD Method (RAPD 방법을 이용한 한국 야생쑥 6종간의 유전적 유연관계 분석)

  • Pyo, Hyun Jin;Choi, Kwan Sam
    • Korean Journal of Agricultural Science
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    • v.23 no.1
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    • pp.99-107
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    • 1996
  • Eighteen nuclear probes were used to examine RFLP(restriction fragment length polymorphism) between six species of Artemisia spp. of Korea. Total DNA from six different species of Artemisia was separately cut with three restrict enzymes. The PstI enzyme was showed to reduce the variation of polymorphisms than the other two enzymes(EcoRl and BamHI). The genetic variation of polymorphism was similar between the Dhewegiki-ssug and Cham-ssug. RAPD analysis was applied to the same six species of Artemisia spp. in order to assess the degree of DNA polymorphism within the Artemisia genus. Six species of Artemisia were evaluated for variation using a set of 11 random 10-mer primers. Nine out of the eleven primers revealed scorable polymorphisms between six species of Artemisia spp. Genetic distances between each of the species were calculated and cluster analysis was used to generate a dendrogram showing phylogenetic relationships between them This result indicates that molecular markers will be more usable in intraspecific study of Artemisia spp. than isoenzyme markers.

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Benthic algal community of Ulleungdo, East coast of Korea (동해안 울릉도 해역의 해조군집)

  • KIM, Sung-Tae;HWANG, Kangseok;PARK, Gyu-Jin;CHOI, Chang Geun
    • Journal of Fisheries and Marine Sciences Education
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    • v.28 no.1
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    • pp.83-90
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    • 2016
  • A subtidal marine benthic algal vegetation at Ulleungdo Island, the eastern coast of Korea was investigated to clarify the community structure and vertical distribution by quadrat method at seven stations in May and August 2014. The total number of marine algal species was 148 species composed of the green algae of 12 species, the brown algae of 40 species and the red algae of 96 species. Mean biomass in dry weight was $94.8g\;dry\;weight\;m^{-2}$ in study sites, $98.1g\;dry\;weight\;m^{-2}$ in upper tidal level, and $86.6g\;dry\;weight\;m^{-2}$ in middle level. The R/P and (R+C)/P value reflecting flora characteristic were 1.9 and 2.3, respectively. Three groups produced by cluster analysis, one including sites Neunggeol, Daepung, Jukdo, second including sites Gongam, Ssangjeongcho and the other including sites Gwaneum, Hangnam, showed meaningful difference in similarity (about 40%), each other. The number of marine algal species and biomass in Ulleungdo Island area were markedly reduced comparing that in the previous studies. This result may suggest probably change of algal vegetation in future, considering the physical and chemical pollutions loaded in the coastal marine environment of this area.

Conceptual Meaning of Purple-series Color Names in the Clothing of Joseon Dynasty Period (조선시대 복식에 나타난 자색계 색명의 개념적 의미)

  • 김순영;남윤자;조우현
    • Journal of the Korean Society of Clothing and Textiles
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    • v.28 no.11
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    • pp.1458-1469
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    • 2004
  • In this study, color names focusing on the purple series, appearing in the clothing of the Joseon Dynasty, were classified systematically, and the conceptual meaning of each name were investigated through various methods. The results are as follows; First, the color names of purple-series were classified systematically. According to the integration scheme of morphemes, color names could be divided into two categories; single names and composite names. Color names could also be classified into universal and limited names according to the areal distribution of literatures. Secondly, the conceptual meaning of the color names of purple-series were considered. The conceptual meaning could be divided into two categories; one 'etymological and dyeing methodological meaning', the other 'color systematic meaning' By studying the dictionary definition of color names, comparing and analyzing the material composition of colors, the etymological and dyeing methodological meaning could be grasped. Furthermore, the color systematic meaning of each name could be grasped through the cluster analysis of L*, a*, b* values measured from the relics of clothing. Thirdly, the conceptual semantic structure were established on the basis of conceptual meanings of purple-series color names. The conceptual semantic structure of purple-series color names is forming discrete structure with the dyeing method and material of dyes as their semantic components.