• 제목/요약/키워드: Four-component

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다변량 통계분석을 이용한 낙동강 창녕함안보 구간의 수질 특성 평가 (The Evaluation of Water Quality Using a Multivariate Analysis in Changnyeong-Haman weir section)

  • 곽보라;김일규
    • 상하수도학회지
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    • 제29권6호
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    • pp.625-632
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    • 2015
  • The study of water environment system using a multivariate analysis in Changnyeong-Haman weir section has been conducted. The purpose of this study is to establish better understanding related water qualities in the Changnyeong-Haman weir section which can provide useful information. The data were consisted of water quality data and algae data including WT(water temperature), pH, DO, EC, COD, SS, T-N, $NH_3-N$, T-P, $PO_4-P$, Chl-a, TOC, d-silica, t-silica, Cyanobacteria, Diatoms, and Green algae. Statistical analyses used in this study were correlation analysis, principal components, and factor analysis. According to correlation analysis on COD and TOC, it revealed that the each value of correlation coefficient was 0.843. On the other result, a negative correlation was observed between diatoms and d-silica. Furthermore, the results of principal component analysis to the overall water quality were classified into four main factors with contribution rate 81.071%.

Component structural analysis on 15kW class wave energy converter

  • Singh, Patrick Mark;Chen, Zhenmu;Choi, Young-Do
    • Journal of Advanced Marine Engineering and Technology
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    • 제39권8호
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    • pp.821-827
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    • 2015
  • This study concentrates on a wave energy converter with floaters that extracts the ocean's energy by moving up and down with the wave motion. The floater is connected to an arm structure, including a hydraulic cylinder that drives a hydraulic generator. This study focuses on a structural analysis of the floater unit, including arm and cylinder components, platform and jack-up system, along with spud columns. Previous studies have been conducted for miniature models for experimentation, but this study focuses on the full-scale model structural analysis. Static structural analysis is conducted using fine numerical grids. Due to the complexity of the whole model, it is analyzed in separate pieces. The floater unit, with arm and cylinder, are combined into one system. The platform is analyzed separately as a single system. There are four jack-up systems for each spud column; only one jack-up system is analyzed, as uniform loads are assumed on each system. There are several load cases for each system, all of which are analyzed thoroughly for stress (von Mises, shear, and normal) and deformation. Acceptable results were obtained for most of the components; unsafe components were redesigned.

하천 미지형 및 하상저질에 따른 갯버들과 달뿌리풀군락의 분포특성에 관한 연구 (A Study on the Distribution Patterns of Salix gracilistyla and Phragmites japonica Communities according to Micro-landforms and Substrates of the Stream Corridor)

  • 전승훈;현진이;최정권
    • 한국조경학회지
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    • 제27권2호
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    • pp.58-68
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    • 1999
  • This study was carried out to verify the distribution patterns of Salix gracilistyla and Phragmites japonica communities known as obligatory riparian species according to physical factors such as micro-landforms, substrates, etc., at Soo-ip stream corridor. Firstly four vegetation types - Salix gracilistyla dominant type, Phragmites japonica dominant type, mixed type of two species, and mixed type of two species to other species, were classified by cluster analysis based on UPGMA-Euclidean distance. Also these vegetation types showed many different distribution patterns in response to the longitudinal and lateral view along the stream corridor and substrate composition. Salix gracilistyla was major component of dominant vegetation types developed at attack point of bending reach and on substrates composed of rock fragments, but contrastly Phragmites japonica was most important component of dominant vegetation types at point bar of bending reach and floodplain, and on substrates composed of soil materials. Secondly the species and environment biplot form CCA strongly supported the vegetation types divided by classification. Namely Salix gracilistyla was closely correlated with rock fragments and steep slope, which is resistant to physical action even though located near running water. But Phragmites japonica showed a high correlation with soil particles sedimented at floodplain by divergent flow.

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Perceived Image of the Jeju Island Dolhareubang: Implications for Online Destination Image in Korea using Q Method

  • Shin, Seunghun;Hunter, William Cannon;Chung, Namho;Koo, Chulmo
    • Asia pacific journal of information systems
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    • 제26권2호
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    • pp.247-262
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    • 2016
  • Almost all Koreans recognize the Dolhareubang as a representative symbol of Jeju. However, as the development of online technology progressed, the image and perception of the Dolhareubang is also expected to change. Thus, this study explored the perceived images of Dolhareubang by focusing on residents in Seoul, Korea using Q methodology. The goal of this research was to evaluate this iconic representation of Jeju as an important component of the island's online tourism destination image. The Q-set was developed from existing literature and defined conceptually in terms of 'value', 'resource', 'story', and 'image'. Thirty five respondents were recruited as P set. Findings indicated four distinctive clusters that perceived the Dolhareubang differently and differences in perceptions were observed in terms of age. The examination of destination image and the exploration of the perceptions of Dolharuebang as a representative of Jeju could contribute to online destination image management or development, which is a crucial component of smart tourism.

중등 환경 교과서의 환경 소양 요소 분석 (Analysis of Environmental Literacy Components for Secondary School Environmental Education Textbooks)

  • 이기영;손연아;신동희
    • 한국환경교육학회지:환경교육
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    • 제19권3호
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    • pp.80-92
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    • 2006
  • The purpose of this study was to make valuable suggestions for improving environmental education(EE) teaching materials. For the purpose of this study, we analyzed four secondary school EE textbooks in the perspective of environmental literacy components. The findings of this study are as follows: (1) As a whole, the EE textbooks tend to focus the understanding environmental knowledge much more than environmental activities. (2) In 'main text' domain of EE textbooks, environmental information, including environmental issue knowledge, is much more focused than environmental attitudes and behavior, including socio-political and environmental issue knowledge. (3) In 'graphic data' domain, environmental information about environmental issue knowledge was most prevalent. (4) Most learning activities focus on 'issue skill' component, rather than 'attitude' and 'action' component. (5) The objectives of EE in the 7th national Curriculum were not explicitly embedded in textbooks and too much is inclined toward 'knowledge' and 'skill'. Accordingly, it is necessary to develop 'module-type' EE textbooks to enable integrative EE. Also, it is suggested to develop specific strategies for linking environmental knowledge and attitude/behavior.

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PIV 기법을 이용한 프로펠러 후류의 3차원 유동 특성 연구 (Study on the Three Dimensional Flow Characteristics of the Propeller Wake Using PIV Techniques)

  • 백부근;김진;김경열;김기섭
    • 대한조선학회논문집
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    • 제44권3호
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    • pp.219-227
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    • 2007
  • A stereo-PIV (particle image velocimetry) technique is used to investigate the vortical structure of the wake behind a rotating propeller in the present study. A four bladed propeller is tested in a cavitaion tunnel without any wake screen. Hundreds of instantaneous velocity fields are phase-averaged to reveal the three dimensional spatial evolution of the flow behind the propeller. The results of conventional 2-D PIV are also compared with those of the stereo-PIV to understand the vortical structure of propeller wake deeply. The variations of radial and axial velocities in the 2-D PIV results seem to be affected by the out-of-plane motion. generating a little perspective error in the in-plane velocity components of the slipstream. The strong out-of-plane motion around the hub vortex also causes the perspective error to vary the axial velocity component a little at the near wake region. The out-of-plane velocity component had the maximum value of about 0.3U0 in the tip vortices and continued its magnitude in the wake region.

INTEGRATED DIAGNOSTIC TECHNIQUE FOR NUCLEAR POWER PLANTS

  • Gofuku, Akio
    • Nuclear Engineering and Technology
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    • 제46권6호
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    • pp.725-736
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    • 2014
  • It is very important to detect and identify small anomalies and component failures for the safe operation of complex and large-scale artifacts such as nuclear power plants. Each diagnostic technique has its own advantages and limitations. These facts inspire us not only to enhance the capability of diagnostic techniques but also to integrate the results of diagnostic subsystems in order to obtain more accurate diagnostic results. The article describes the outline of four diagnostic techniques developed for the condition monitoring of the fast breeder reactor "Monju". The techniques are (1) estimation technique of important state variables based on a physical model of the component, (2) a state identification technique by non-linear discrimination function applying SVM (Support Vector Machine), (3) a diagnostic technique applying WT (Wavelet Transformation) to detect changes in the characteristics of measurement signals, and (4) a state identification technique effectively using past cases. In addition, a hybrid diagnostic system in which a final diagnostic result is given by integrating the results from subsystems is introduced, where two sets of values called confidence values and trust values are used. A technique to determine the trust value is investigated under the condition that the confidence value is determined by each subsystem.

미국 고급 패션백화점의 페이스북 페이지 커뮤니케이션 전략 (The Facebook page communication strategy of high-end fashion department stores in the United States)

  • 김성희
    • 패션비즈니스
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    • 제17권4호
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    • pp.177-190
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    • 2013
  • The purpose of this study is 1) to investigate the types of upscale fashion department stores' Facebook page contents, 2) to compare the types of Facebook page contents with the department stores, and 3) to explore the dimensions of the Facebook page components and their relations. For the study, three preeminent department stores in social media marketing were chosen: Bergdorf Goodman, Barneys New York, and Saks Fifth Avenue. Three hundred sixty five contents of these department stores' pages were investigated, which were uploaded from February 1st to March 31st of 2013. Content analysis, correspondence analysis, and categorical principal component analysis were used for the research. The result showed that there are four important types of contents in pages: product-related contents, fashion-related contents, department stores-related contents, and the contents of communicating with users. And these components of contents were related with department stores distinctively. The two dimensions of the page components were revealed: the basic components (contents, 'like', 'share', and 'comments') and the additional components (links and photos). Among contents, the introduction of products was appealed but news and events were not liked by users; the contents without a photo were not linked to additional information either.

Amperometric Detection of DNA by Electroreducation of O2 in an Enzyme-Amplified Two-Component Assay

  • Yoon Chang-Jung;Kim Hyug-Han
    • 전기화학회지
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    • 제7권1호
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    • pp.44-48
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    • 2004
  • The two-component type enzyme amplified amperometric DNA assay is described to use an ambient $O_2$ of the substrate of the DNA labeling enzyme. Although the assay detects DNA only at > 0.5M concentration, a concentration $\~10^6$ fold higher than the sandwich-type enzyme amplified amperometric DNA assay, it can be run with an always available substrate. The assay utilizes screen-printed carbon electrodes (SPEs) which were pre-coated by a co-electrodeposited film of an electron conducting redox hydrogel and a 37-base long single-stranded DNA sequence. The DNA in the electron conducting film hybridizes and captures, when present, the 37-base long detection-DNA, which is labeled with bilirubin oxidase (BOD), an enzyme catalyzing the four-electron reduction of $O_2$ to water. Because the redox hydrogel electrically connects the BOD reaction centers to the electrode, completion of the sandwich converts the film from non-electrocatalytic to electrocatalytic for the reduction of $O_2$ to water when the electrode is poised at 200 mV vs. Ag/hgCl. The advantage or the assay over the earlier reported sandwich type enzyme amplified amperometric DNA assay, in which the amplifying enzyme was horseradish peroxidase, is that it utilizes ambient $O_2$ instead of the less stable and naturally unavailable $H_2O_2$.

섬유소분해균의 분리 및 그의 생리학적 특성 (Isolation of Cellulolytic Microorganisms and their Physiological Characteristics)

  • 홍순우;하영칠;민경희;이영하
    • 미생물학회지
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    • 제14권1호
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    • pp.17-24
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    • 1976
  • Celluloytic microorgnasims were isolated form the various sources and four of them were identified as Trichoderma roningi, Aspergillus niger, Penicillium chrysogenum, and Streptomyces sp. The induction of extracellular5 cellulase of these species in the liquid culture media containing carboxymethylcellulose (CMC) or Avicel as inducer showed that CMC was a better effective inducer for the production of CMCase(Cx cellulase component) as well as Avicelase(C$_{1}$ cellulase component) than Avicel. It is believed that certain hydrolysis products of cellulose(CMC) could serve as an inducer for an enzyme synthesis. In T. roningi, Asp. niger, and Strptomyces sp., the optimum temperature of CNCase on CMC-culture medium was 50.deg. but temperature around 40.deg.C was found to be optimum for the activities of CMCase prepared from P.ehrysogenum. The optimum temperature for Avicelase activitiles on Avicel-culture media of T. roningi and P. chrysogenum was $40{\circ}C$ whereas temperature $50{\circ}C$ was found to be optimum for Avicelase from A.niger and Streptomyces sp. The optimal activities of these CNCase and Avicelase prepared from. T. ronigi, Pen.chrysogenum and Streptomyces sp. were found similarly to be at pH's around 5.4 and 6.0 while pH 4.8 was optimum for the activities of CMCase and Avicelase from A.niger, indicating that A.niger in acidic media would yield an enzyme of high activity.

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