• Title/Summary/Keyword: Core Component

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Analysis of Flame Generated Turbulence for a Turbulent Premixed Flame with Zone Conditional Averaging (영역분할조건평균법에 근거한 난류예혼합화염내 난류운동에너지 생성에 관한 연구)

  • Im, Yong-Hoon;Huh, Kang-Yul
    • 한국연소학회:학술대회논문집
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    • 2003.12a
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    • pp.49-56
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    • 2003
  • Mathematical formulation of the zone conditional two-fluid model is established to consider flame-generated turbulence in premixed turbulent combustion. The conditional statistics of major flow variables are investigated to understand the mechanism of flame generated turbulence. The flow field in burned zone shows substantially increased turbulent kinetic energy, which is highly anisotropic due to reaction kinematics across thin flamelets. The transverse component of rms velocities in burned zone become larger than axial component in the core of turbulent flame brush. The major source or sink terms of turbulent kinetic energy are the interfacial transfer by the mean reaction rate and the work terms by fluctuating pressure and velocity on a flame surface.

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Numerical Algorithm for Power Transformer Protection

  • Park, Chul-Won;Suh, Hee-Seok;Shin, Myong-Chul
    • KIEE International Transactions on Power Engineering
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    • v.4A no.3
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    • pp.146-151
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    • 2004
  • The most widely used primary protection for the internal fault detection of the power transformer is current ratio differential relaying (CRDR) with harmonic restraint. However, the second harmonic component could be decreased by magnetizing inrush when there have been changes to the material of the iron core or its design methodology. The higher the capacitance of the high voltage status and underground distribution, the more the differential current includes the second harmonic during the occurrence of an internal fault. Therefore, the conventional second harmonic restraint CRDR must be modified. This paper proposes a numerical algorithm for enhanced power transformer protection. This algorithm enables a clear distinction regarding internal faults as well as magnetizing inrush and steady state. It does this by analyzing the RMS fluctuation of terminal voltage, instantaneous value of the differential current, RMS changes, harmonic component analysis of differential current, and analysis of flux-differential slope characteristics. Based on the results of testing with WatATP99 simulation data, the proposed algorithm demonstrated more rapid and reliable performance.

Determination of Harvest Time and Nominal Origin from Cynanchi wilfordii Radix (백수오(白首烏)의 명칭과 수확 시기 연구)

  • Lee, Je-Hyun;Kweon, Kee-Tae
    • The Journal of Korean Medicine
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    • v.33 no.1
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    • pp.160-168
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    • 2012
  • Objectives: Cynanchi wilfordii Radix has commonly been used with or instead of Polygoni multiflori Radix in Korea. The purpose of this study was to investigate their history in the traditional Oriental medical literature and quantitative determination of conduritol F from Cynanchi wilfordii Radix according to various harvest times. Methods: We conducted studies of the traditional Oriental medical literature and analysis of the component, conduritol F, simultaneously. Efficacy and origin of Cynanchi wilfordii Radix in literature study, time of harvest in component research. Chromatographic analysis performed using Silica(2) 100A column (Phenomenex 5 um, 250 mm 4.6 mm) with a mixture of acetonitrile and water (98 : 2)(v/v). The analyses detected at UV (210 nm). Results: Conduritol F was detected in Cynanchi wilfordii Radix, but in Cynanchi auriculati Radix was not. We indicate that conduritol F is as a distinguishable indicator with other materia medica. We think the proper harvesting time is October and November. Conclusions: Measures of trunk control were significantly related with values of dynamic balance and gait. Based on these results, trunk control is an essential core component of balance and gait. Trunk control training programs after stroke should be developed and emphasized.

A Study on the Structural Analysis of the Port Competition Power by FSM Method (FSM법에 의한 항만경쟁력의 구조분석에 관한 연구)

  • 여기태
    • Journal of the Korean Institute of Navigation
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    • v.25 no.4
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    • pp.477-486
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    • 2001
  • Although the ports are actually competing with various strategies, the definition and structural understanding of port competitive power are not known very much. Therefore this study has launched from this fact, and has the objective of obtaining the structural model of the competitive power, and understanding the components of the port competitive power. The following are the results of the study. First, the process began by abstracting the components that composed the port competitive power through recent research, and grouping it by the most core components using the KJ method. Also, by using the FSM(Fuzzy Structural Modeling) method to understand the structure of the grouped components, and the structural model of the port competitive power was able to obtain as the result. Second, when analyzing the obtained structural model, port expenses, main trunk location, port congestion and port facility came out to be the most important component groups, and especially port expenses was the most effective component that effected all the other components overall. Third, the component groups that were relatively less important, effected by most of the other components, and located on the top level of the structure model were the hinterland accessibility, port ownership, customs duties speed, and large ship port entrance possibility etc. Fourth, the results of this study will be able to be used when establishing competing strategies for our country's ports by proposing the relatively important components with the port competitive rower considered.

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The SWG Component Technology Classification Scheme Researchthrough the Technology Trend Analysis

  • Son, Hong Min;Hu, Jong Wan
    • Journal of Korea Water Resources Association
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    • v.48 no.11
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    • pp.945-955
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    • 2015
  • The technology of the SWG (Smart Water Grid) as one of most important national projects results in significant assignment that is closely associated with systematic management and effective operation. The individual component technics are required to establish directory and classification for the purpose of effectively managing their information related to research and development (R&D). The national science technology (S&T) standard classification tree which results in the representative example has been established with an intention to manage R&D information, human resource, and budget. It has been also revised every five years and then used in the various fields related to the evaluation, administration, and prediction of the national R&D projects. In addition, the standard classification system for R&D projects has been widely used in the UNESCO (United Nations Educational, Scientific and Cultural Organization) and EU (European Union) since the Frascati Manual was established in the Organization for Economic Cooperation and Development (OECD). Therefore, it is necessary for SWG techniques to develop the standard S&T classification tree for research management and evaluation. For this, it is essential to draw the core techniques for the SWG, which are incorporated with IT (Information Technology), NT (Nano Technology), and BT (Biology Technology).

An Analysis on the Visual Structure from the Building Area around An-ap Pond (안압지 호안 건물지의 조망 경관구조 분석)

  • 박경자;이관규;양병이
    • Journal of the Korean Institute of Landscape Architecture
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    • v.29 no.2
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    • pp.14-21
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    • 2001
  • This study aims to analyze visual structure by evaluating the view from five building sites around An-ap pond, and attempt to determine which site commands the best view and will provide the most active use. The results of this study can be summarized as follows: According to the questionnaire survey of experts on the relations of dominancy-subordination(´chu-jong´), vacancy-solidness(´heo-sil´), sparsity-density(´so-mil´) based on ancient oriental Yin-Yang theory and analysis of visual structure on angle of elevation, depression, and the landscape-component ratio to be seen through five building sites around the west of An-ap pond, building site three was selected as the building site which has the best landscape. Therefore, it is estimated that building site three played the role of core-building site. According to the result of correlation analysis, the greater the increased in the component ratio of sky, mountain ,the greater the degree of harmony within the landscape. As well, the degree of harmony increased when the landscape component ratio of a distant view was greater than that of a near view. Moreover, it was proved that the relationships of ´chu-jong´, ´heo-sil´, ´so-mil´ are correlative, not independent.

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Meteorological Response against Yield and Yield Component of Rice in Chungnam and Daejeon Area (충남지역에서 기상요소가 벼의 수량과 수량구성요소에 미치는 영향)

  • An, Jong-Beom;Cho, Jin-Woong
    • Korean Journal of Agricultural Science
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    • v.37 no.2
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    • pp.177-189
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    • 2010
  • These studies were conducted to analysis for weather reaction on the growth and yield component according to meterological elements used Vector Autoregressive Regression(VAR) Model at Daejeon, Hongseong, Geumsan, Nonsan, and Yesan to core of center to Chungnam area in Rice. Reaction of cultivars according to change of meterological elements for growth and yield component effected on heading time in Gancheokbyeo and Mananbyeo, grain number of a spike in Gancheokbyeo, ratio of ripeness in Gancheokbyeo and Geumobyeo 1, amount of milled rice in Geurubyeo and Ansanbyeo, and 1,000 grains weight in Gancheokbyeo, Dasanbyeo, and Hwajinbyeo. An effect on the growth and yield components of meterological elements were influenced by heading date, 1,000 grain weight and ratio of repening as sunshine hours. The cultivars in sensitive reaction for change of weather condition were classified to 14 varieties including Gerubyeo et al., insensitive cultivars were classified to 66 varieties including Gyehwabyeo et. al.

APPARENT INWARD MOTION OF THE PARSEC-SCALE JET IN THE BL LAC OBJECT OJ287 DURING THE 2011-2012 γ-ray FLARES

  • SAWADA-SATOH, S.;AKIYAMA, K.;NIINUMA, K.;NAGAI, H.;KINO, M.;D'AMMANDO, F.;KOYAMA, S.;HADA, K.;ORIENTI, M.;HONMA, M.;SHIBATA, K.M.
    • Publications of The Korean Astronomical Society
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    • v.30 no.2
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    • pp.429-432
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    • 2015
  • We present a kinematic study of the parsec-scale radio jet in OJ 287, one of the most studied BL Lac objects, during ${\gamma}$-ray flares, to explore the relation between parsec-scale radio jet activity and ${\gamma}$-ray emission. The 22-GHz light curve of OJ 287 show three obvious flare events around 2011 May, 2011 October, and 2012 March. The second radio flare occurred during the ${\gamma}$-ray flaring period, and the third radio flare seemed to precede the ${\gamma}$-ray flare by one month. One jet component moved outward with respect to the core component with an apparent superluminal speed (~ 11c) from 2010 November to 2011 November. Then it changed direction, moving apparently inward in 2011 November, when the ${\gamma}$-ray flare occurred. The observed apparent inward motion of the jet at 22 GHz could be caused by a new jet component, unresolved at 22 GHz, in the innermost region.

Acupuncture in Sport Recovery: A Brief Review

  • CHAPLEAU, Christopher
    • The Korean Journal of Food & Health Convergence
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    • v.6 no.2
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    • pp.23-26
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    • 2020
  • Active and therapeutic sport recovery is becoming a popular and important component in approving performance for pro and recreational athletes alike. It is also helping in the realm of injury prevention. In the search of finding modalities that are widely effective, natural, and safe, acupuncture is a viable and cost-effective treatment for helping athletes achieve this goal. More direct related research is needed, but testimonials from pro athletes and the body of research that currently exists provides powerful evidence on acupunctures ability to help with enhancing recovery. Specializing in acupuncture and exercise science, Chris integrates acupuncture into musculoskeletal rehabilitation therapy or fitness training for pain modulation, speedy recovery, and enhanced performance. Clients can choose to focus on one-on-one corrective exercise therapy, manual and massage therapy, or acupuncture. However, for best results, Chris recommends all three. Other modalities that he uses in therapy are acu-taping, herbal therapy, nutrition supplementation, cupping, guasha, and stretching techniques. The corrective exercise component is one-on-one body balancing management, focusing on strength and conditioning, post physical rehab - exercise therapy, integrative sport specific exercise, weight loss, core strengthening, dynamic lumbar stabilization, active recovery techniques, and myo-fascial release techniques. The acupuncture component focuses on sport injuries, myofascial pain, peripheral neuropathy, arthritis, facial rejuvenation, stress, smoking cessation, addiction detoxification program, weight management, sport recovery and performance.

Effect of test-caused degradation on the unavailability of standby safety components

  • S. Parsaei;A. Pirouzmand;M.R. Nematollahi;A. Ahmadi;K. Hadad
    • Nuclear Engineering and Technology
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    • v.56 no.2
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    • pp.526-535
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    • 2024
  • This paper proposes a safety-critical standby component unavailability model that contains aging effects caused by the elapsed time from installation, component degradation due to surveillance tests, and imperfect maintenance actions. An application of the model to a Motor-Operated Valve and a Motor-Driven Pump involved in the HPIS of a VVER/1000-V446 nuclear power plant is demonstrated and compared with other existing models at component and system levels. In addition, the effects of different unavailability models are reflected in the NPP's risk criterion, i.e., core damage frequency, over five maintenance periods. The results show that, compared with other models that do not simultaneously consider the full effects of degradation and maintenance impacts, the proposed model realistically evaluates the unavailabilities of the safety-related components and the involved systems as a plant age function. Therefore, it can effectively reflect the age-dependent CDF impact of a given testing and maintenance policy in a specified time horizon.