• 제목/요약/키워드: Song type

검색결과 4,422건 처리시간 0.039초

갈색 Type I 다이아몬드의 고압 열처리에 따른 표면 흑연화 생성 연구 (Surface Graphite Formation of the Brown Colored Type I Diamonds During High Pressure Annealing)

  • 송정호;송오성
    • 한국세라믹학회지
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    • 제49권6호
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    • pp.614-619
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    • 2012
  • We investigated color and graphite layer formation on the surface of Type I tinted brown diamonds exposed for 5 minutes under a high-pressure high-temperature (HPHT) condition in a stable graphite regime. We executed the HPHT processes of Process I, varying the temperature from $1600^{\circ}C$ to $2300^{\circ}C$ under 5.2 GPa pressure for 5 minutes, and Process II, varying the pressure from 4.2 to 5.7 GPa at $2150^{\circ}C$ for 5 minutes. Optical microscopy and micro-Raman spectroscopy were used to check the microstructure and surface layer phase evolution. For Process I, we observed a color change to vivid yellow and greenish yellow and the growth of a graphite layer as the temperature increased. For Process II, the graphite layer thickness increased as the pressure decreased. We also confirmed by 531 nm micro-Raman spectroscopy that all diamonds showed a $1440cm^{-1}$ characteristic peak, which remained even after HPHT annealing. The results implied that HPHT-treated colored diamonds can be distinguished from natural stones by checking for the existence of the $1440cm^{-1}$ peak with 531 nm micro-Raman spectroscopy.

고성능감수제가 시멘트 초기 수화에 미치는 영향 (Effect of Superplasticizer on the Early Hydration Ordinary Potland Cement)

  • 나승현;강현주;송영진;송명신
    • 한국세라믹학회지
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    • 제47권5호
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    • pp.387-393
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    • 2010
  • To improve concrete quality one of the most widely used chemical admixtures is polycarboxylate type superplasticizer. Unlike lignosulfonate and naphthalene-sulfonate, it has high dispersion property and excellent sustainable dispersion property for cement and concrete. Thus, polycarboxylate type superplasticizer has been widely used as a high-performance water reducing admixture together with silica fume in high-performance concrete and other applications for the dispersion of high-strength concrete over 100 MPa. However, even though there have been many studied on the dispersion of concrete by the structure of polycarboxylate type superplasticizer, there have a few studied that clarified the relationships between its rheological properties and microstructure properties in the early hydration behavior of ordinary portland cement. To investigate the correlations between the rheological properties and microstructure of cementitious materials with polycarboxylate type superplasticizer, this study experimented on the rheology, pore structure, heat evolution, and consistency in early hydration as well as on the compressive strength by early dispersion characteristics.

A Case Study on Partnership Types between Network Operators & Netflix: Based on Corporate Investment Model

  • Minzheong, Song
    • International Journal of Internet, Broadcasting and Communication
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    • 제12권1호
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    • pp.14-26
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    • 2020
  • We categorize partnership types between network operators and a global video streaming or over-the-top service provider, Netflix from 2011 to the first quarter 2018. The options are based on the integration of over-the-top (OTT), Netflix with pay TV and telecommunication operators in the form of carrier billing, access to over-the-top (OTT) via devices or the development of their tariff plans. Options of the Type 3, 'cooperation' or the Type 4, 'agreement' entails a kind of the technical involvement between two partners and commercial agreement. The types of partnership are evolving from one to others. Some partnerships have characteristics of more than one type. The majority of technical or service integration cooperation of Type 3 entail bundling and marketing promotion of Type 2 and Type 1. Similarly, the 'agreement' of Type 4, co-branded or white-label service initiative entail tariff or device user interface (UI) integration of the 'cooperation' of Type 3 and joint marketing initiatives of Type 1.

역극성 전압인가와 나사형 전극을 이용한 복합방전형 오존발생기의 특성 (The Characteristics of the Complex Discharge Type Ozonizer using Applied Voltage of a Inverse-Polarity and a Screw Type Electrode)

  • 송현직
    • 조명전기설비학회논문지
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    • 제25권9호
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    • pp.80-85
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    • 2011
  • In this paper, complex discharge type ozonizer with a screw type electrode has been designed and manufactured for environmental improvement using low power and high efficency ozoniazer. The complex discharge type ozonizer is equipped with three electrodes{central electrode(CE), internal electrode(IE) and external electrode(EE)}. Ozone of the complex discharge type ozonizer is generated by superposition of silent discharge and surface discharge in discharge space as a screw type CE and IE are respectively applied to AC high voltage of inverse-polarity has $180[^{\circ}]$ phase difference, EE is common electrode. In this time, when oxygen has been used as supplied gas, the maximum values of ozone concentration, ozone generation and ozone yield were obtained as 8,334[ppm], 3,249[mg/h] and 65.3[g/kwh].

고속도 개극 시의 복합소호 가스차단기의 차단특성 (Interruption Capability of Hybrid Type GCB with High Opening Speed)

  • 송기동;정진교;박경업
    • 대한전기학회논문지:전기기기및에너지변환시스템부문B
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    • 제54권9호
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    • pp.408-413
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    • 2005
  • This paper presents the basic design technology on the hybrid type GCB(gas circuit breakers) through the test results. The three type hybrid interrupters according to the arrangement of the thermal expansion chamber and the puffer cylinder(they are called 'serial type', ' parallel/exchanged type ,' and ' parallel/separated type ' respectively in this work) were designed and manufactured and then the tests of operating characteristics and interrupting were performed using a simplified synthetic test facility. The interruption capability with the type and the opening speed and the pressure rise which is required to interrupt were examined. The change of pressure rise with the number of interruption was given quantitatively and therefore the pressure rise can be predicted. Finally, it was shown that the interruption capability tends to increase with the increasing of opening speed in the puffer type; however, the hybrid type interrupter has a different interruption characteristic.

한국인(韓國人)의 교합(咬合)과 상악치열궁(上顎齒列穹)에 관(關)한 형태학적(形態學的) 연구(硏究) (A Morphological study on Occlusion and Maxillary dental Arch in Korean)

  • 김성일
    • 대한치과보철학회지
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    • 제9권1호
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    • pp.9-15
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    • 1969
  • The purpose of this study was to examine arch form, occlusion in centric occlusion. Male 561 case, Female 305 case were impressioned with alginate impression material, and plaster models were made. Occlusion and maxillary dental arch were studied on plaster models in Korean adults aged from 18 to 60 Years. The results were as follows. 1. The upper dental arch was U-type(57.77%), O-type(23.52%), V-type(18.71%) in male, and U-type(60.66%), O-type(27.11%), V-type(12.13%) in female. 2. The commonest type of the anterior bite was 1-form($68.09{\pm}1.97%$) in male, ($72.46{\pm}2.56%$) in female, and posterior bite was 1-form($65.06{\pm}2.01%$) in male, ($69.51{\pm}2.64%$ in female. 3. In the maxillary dental arch U-type was frequented and the relationship of occlusion in upper and lower dental arch was mainly 1-form.

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