• 제목/요약/키워드: firing

검색결과 2,056건 처리시간 0.027초

도자기용 아연결정 유약의 결정 제어를 위한 연구 (A study on crystalline control of zinc crystal glaze for ceramics)

  • 이현수;이지연
    • 한국결정성장학회지
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    • 제33권6호
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    • pp.234-243
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    • 2023
  • 유약원료 내의 ZnO와 SiO2의 조성과 소성요건에 따라 생성되어 표면으로 석출된 아연결정은 매우 장식성이 높아 선호된다. 하지만 아연결정유약은 대부분 소성온도가 높고 소성온도 폭이 좁아 상용유약으로 사용하기 어렵다. 따라서 본 연구에서는 아연결정유약 제조 시 사용하는 주원료인 frit를 혼용하여 공융효과를 이용하면 일반적인 아연결정유약의 소성온도를 1270℃보다 아연결정의 유약 생성온도를 낮출 수 있을 것으로 기대하였다. 그 결과 Frit 혼용 유약에서는 아연결정의 생성온도가 낮아질 뿐 아니라 1230~1270℃로 소성온도 폭이 넓어져 안정적으로 결정이 생성되는 유약을 개발할 수 있었다. 소성 최고온도를 1230~1250℃로 낮추고 냉각 시 유지온도를 약 950℃까지 낮출 수 있었으며, 경제적으로 효과적인 유약을 개발할 수 있었다. Frit 혼용으로, 유약의 조성에 따라 냉각 시 유지온도는 아연결정의 재결정화에 영향을 주는 것으로 나타났으며 이때 결정형을 조절할 수 있다. 또한, 조핵제의 활용으로 결정 생성 량과 형태의 제어가 가능하다.

Mathematical Models for Hit Probabilities using Small-arms against Fast Low Flying Aircraft

  • Park, Chan-Tae
    • 한국국방경영분석학회지
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    • 제7권1호
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    • pp.81-117
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    • 1981
  • Mathematical models for hit probabilities of small arms are developed in order to estimate the expected hits on an aircraft for certain altitudes and air speeds. A model for the firing lead angle is developed for cases when the distribution of hits is normal and the firing angle is from 20 degrees to 160 degrees. probabilities of hit for single and multiple shots at various altitudes are calculated. Tables are given showing the probability of hits and kill for targets flying at high speed above 500 feet from ground level.

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초임계 오일 연소 보일러의 동특성 예측 연구 - 650MWe급 화력발전소의 Load Runback 모사 (Dynamic performance prediction of a Supercritical oil firing boiler - Load Runback simulation in a 650MWe thermal power plant)

  • 양종인;김정래
    • 한국연소학회:학술대회논문집
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    • 한국연소학회 2014년도 제49회 KOSCO SYMPOSIUM 초록집
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    • pp.19-20
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    • 2014
  • Boiler design should be desinged to maximize thermal efficiency of the system under imposed load requirement and a boiler should be validated for transient operation. If a proper prediction is possible on the transient behavior and transient characteristics of a boiler, one may asses the performance of boiler component, control logics and operation procedures. In this work, dynamic modeling method of boiler is presented and dynamic simulation of load runback scenario was carried out on suprecritical oil-firing boiler.

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수광재와 백토조합물에서의 기포형성에 관한 연구 (The Study on Foam Formation in Waterslag-Bentonite System)

  • 김종희;송한식
    • 한국세라믹학회지
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    • 제14권4호
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    • pp.248-255
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    • 1977
  • The effect of firing temperature, soaking time and batch composition upon the glass phase and pore formation as well as their distribution in slag foamed glass was investigated. Sulfur dioxide gas produced by the oxidation and reduction of metal sulfide in waterslag was attributed to foam forming agent. Slag foamed glass matrix was mainly composed of 35~60% glas phase and melilite crystalline phase. The increment of bentonite addition in batch lowered the foam forming temperature in studied system. The result showed also that the foam size distribution was broadened as th firing temperature wa inbereased.

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Vernier 모드 2-듈 TCSC의 특성 해석을 위한 싸이리스터 점호각 계산 (Calculation of the Thyristor Firing Angles to Analyze the Characteristics of Two-Module TCSC in Vernier Mode)

  • 정교범
    • 전력전자학회논문지
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    • 제5권1호
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    • pp.54-62
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    • 2000
  • 본 논문은 Vernier 모드에서 운전하는 2-모듈 TCSC로 구성된 전력송전시스템의 특성 해석을 위하여 싸이리스터 점호각 계산을 푸리에 공간에서 수행한다. 이를 위하여 싸이리스터 스위칭 함수를 이용하여 TCSC 리액터 전류에 관한 연립방정식을 구하였다. TCSC 모듈의 등가 임피던스가 전력송전 시스템이 요구하는 특정값을 갖게 하는 싸이리스터 점호각을 수치해석 방법을 사용하여 구하고, TCSC 전력송전시스템의 정상상태 특성을 해석하였다. 또한 EMTP 시뮬레이션을 수행하여 푸리에 공간에서의 점호각 계산의 타당성을 시평면상에서 검증하였다.

Customer Selection in CRM implementation: Firms′strategies in the competitive market with network externality

  • Kim Eun-Jin;Lee Byeong-Tae
    • 한국경영과학회:학술대회논문집
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    • 한국경영과학회 2003년도 추계학술대회 및 정기총회
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    • pp.183-186
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    • 2003
  • Customer profitability recognition is easier with CRM enabling technologies and the strategy of firing unprofitable customers prevails in the market. However, in the digital and Internet age, network externality is becoming more important. Therefore, the concern over firing unprofitable customers has increased. Our research is intended to develop strategic guidance for customer selection when firms implement CRM in the market with network externality.

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골회자기의 소지 및 소성과정에 관한 연구 (A Study on Composition and Firing Temperature of Bone China Body)

  • 이응상;이성희
    • 한국세라믹학회지
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    • 제26권1호
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    • pp.67-72
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    • 1989
  • In order to define the composition range of bone china body with use of calcium phosphate, kaolin, quartz and feldspar as raw materials, we varied calcium phosphate from 40 to 55wt/o and selected basic composition by the change of raw materials in ternary system. After these bodies were fired at 120$0^{\circ}C$, 123$0^{\circ}C$, 125$0^{\circ}C$ and 128$0^{\circ}C$ their properties were closely tested to determine the compositions and firing conditions of bone china body.

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SiC 질 공업용 도자기 개발에 관한 연구 (Study on the Development of SiC-containing Technical Porecelain Body)

  • 박정현;배원태;권오훈
    • 한국세라믹학회지
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    • 제19권1호
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    • pp.5-12
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    • 1982
  • SiC-containing by-product from the surface abrasion process of porcelain cores is used as a starting material to develop the SiC-containing technical porcelain bodies. To prevent the bloating phenomenon of by-product specimen at firing temperature, it is acid treated. In order to enhance the workability and to lower the firing temperature of bodies, clay is added. Body containing 25% clay and 75% by-product fired at 135$0^{\circ}C$ showes extremely high thermal shock resistance and acid resistance.

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사격 외란을 받는 포구동장치의 최적제어기 구성에 관한 연구 (Analysis to design optimal controller for the gun servo system with known firing disturbance)

  • 김광태;최중락;김영수
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1988년도 한국자동제어학술회의논문집(국내학술편); 한국전력공사연수원, 서울; 21-22 Oct. 1988
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    • pp.639-642
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    • 1988
  • In this paper, the problem of regulation in the presence of a known firing disturbance is considered. We show how one can apply a disturbance-utilizing control(DUC) theory to a actual gun servo model. Applied disturbance-utilizing control theory is established by combining LQ regulator and reduced order observer in the discrete time domain. To see the performance of the applied method, computer simulation results are given.

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토기의 소성온도에 따른 미세조직 비교연구 (Microsturucture of pottery by the measurement of firing temperature)

  • 홍종욱;정광룡
    • 보존과학연구
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    • 통권15호
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    • pp.1-20
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    • 1994
  • A typology was established for 15 pottery artefacts at Chejuisland. Conjectured methods of manufacture were confirmed by radiography X-ray diffraction. Scanning electron microscopy etc. The compositions and mineralogy of $500^{\circ}C$ to $1200^{\circ}C$ was measured and compared with those of microstructure. The mechanism of sintering was impurity-initiated, liquid-phase sintering. The making, firing, and sometimes exploding of the figurines may have been the prime function of the pottery at this site rather than being manufactured as permanent, portable object.

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