• 제목/요약/키워드: temperature stable characteristics

검색결과 961건 처리시간 0.031초

진공증착중합법에 의해 제조된 6FDA/DDE 폴리이미드박막의 열처리에 따른 특성에 관한 연구 (A study on the curing characteristics of polyimide thin film fabricated by vapor deposition polymerization)

  • 이봉주;김형권;진윤영;박구범;김영봉;이덕출
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1997년도 하계학술대회 논문집 C
    • /
    • pp.1552-1554
    • /
    • 1997
  • In this paper, thin films of PI were fabricated VDPM of dry processes which are easy to control the film's thickness and hard to pollute due to volatile solvents. From FT-IR, PAA thin films fabricated by VDP were changed to PI thin films by thermal curing. From AFM and ellipsometer experimental, the higher curing temperature is, the films thickness decreases and reflectance increases. Therefore, PI could be fabricated stable by increasing curing temperature.

  • PDF

가스터어빈 연소기의 화염 안정화와 제어 (Flame Stabilization and Control in Gas Turbine Combustor)

  • 최경민
    • 한국분무공학회지
    • /
    • 제8권4호
    • /
    • pp.24-30
    • /
    • 2003
  • This paper presents the characteristics of lifted height and flame length from non-premixed jet flames in highly preheated air to investigate the detail combustion mechanism in the gas turbine or HCCI engine, etc. Special attention was paid to the effect of preheated air temperature, oxygen concentration and fuel injection flow rate on flame length and lifted hight. By using highly preheated air, stable flames were formed even in low oxygen concentration condition. The lifted height increased with decreasing preheated air temperature, where the flame length showed opposed phenomena. The flamelet model, which is thought to have very thin flamelet, is difficult to applicable to the present flame conditions which is formed In low oxygen concentration in highly preheated air.

  • PDF

A Diagnostic Method of Control-in/out in the Glass Furnace

  • Cho, Jin-Hyung;Lee, Sae-Jae;Jang, Do-Soo
    • 산업경영시스템학회지
    • /
    • 제29권1호
    • /
    • pp.151-154
    • /
    • 2006
  • The high degree of viscosity and the non-Newtonian fluid dynamics characterizes the process inside a glass furnace. Because the temperature is fluctuating in very short time-intervals, it is hard to determine that the status of its fluctuation is stable or unstable. Usually Shewhart-chart is used to determine the control status. However because of the characteristics of the temperature fluctuations in the glass furnace it does not directly serve the purpose here. Therefore we suggest using ARIMA to diagnose control status and confirm that the method using ARIMA can be a better tool than Shewhart-chart.

2차원 광밴드갭 나노레이저 (Two-Dimensional Photonic Bandgap Nanolasers)

  • Lee, Y. H.;Hwang, J-K;H.Y. Ryu;Park, H. K.;D. J. Shin
    • 한국광학회:학술대회논문집
    • /
    • 한국광학회 2001년도 제12회 정기총회 및 01년도 동계학술발표회
    • /
    • pp.2-3
    • /
    • 2001
  • Characteristics of two-dimensional slab photonic crystal lasers will be summarized. Room temperature c.w operation is demonstrated at 1.6 $\mu\textrm{m}$ by using InGaAsP slab-waveguide triangular photonic crystal on top of wet-oxidized aluminum oxide. Recently, 2-D PBG structures have attracted a great deal of attention due to their simplicity in fabrication and theoretical study as compared to the three-dimensional counterparts [1]. Air-guided 2-D slab PBG lasers were reported by Caltech group (2). However, this air-slab structure is mechanically fragile and thermally unforgiving. Therefore, a new structure that can remove this thermal limitation is dearly sought after for 2-D PBG laser to have practical meaning. In this talk, we report room-temperature continuous operation of 2-D photonic bandgap lasers that are thermally and mechanically stable.(omitted)

  • PDF

크롬코팅 처리된 금형에서 박판의 온간 딥드로잉 성형성에 관한 연구 (A Study on the Warm Deep Drawing Ability of Sheets on Cr-Coating Die)

  • 서대교;이재동;최치수;최이천;김헌영
    • 소성∙가공
    • /
    • 제9권2호
    • /
    • pp.186-192
    • /
    • 2000
  • Some deep drawing characteristics to the elevated temperatures were investigated for the SCPI steel sheets by using the Cr-coated die. For this investigations, six steps of temperature ranges, from room temperature to 25$0^{\circ}C$, and six kinds of drawing ratio, from 2.4 to 2.9 were adopted. As a result, the limiting drawing ratio, maximum drawing force, and the maximum drawing depth were sensitively affected by the elevated temperatures, and the more stable thickness strain distribution was observed to the elevated temperatures. Some experimental results were compared with analytical results using the DYNA-3D code.

  • PDF

열원의 위치에 따른 평판형 히트파이프의 열적 성능 (Thermal Performance of Flat-strip Heat Pipe with Various Heat Source Locations)

  • 박수용;부준홍
    • 대한기계학회:학술대회논문집
    • /
    • 대한기계학회 2004년도 춘계학술대회
    • /
    • pp.1406-1411
    • /
    • 2004
  • A series of experiments was conducted to examine characteristics of a grooved flat-strip heat pipe having multiple heat sources. The inner grooves of the heat pipe have the aspect ratio of 1 to $2.5(0.42{\times}1.05$ mm) whose pitch was 0.6 mm. Four block heaters ($10{\times}20$ mm) were placed in the evaporator section at intervals of 20 mm and six different heating modes were tested. The maximum surface heat flux of 80 $W/cm^2$ was achieved while the operating temperature was kept below $100^{\circ}C$, In the nearest heating mode (from the condenser location), the heat pipe exhibited more stable temperature distribution than the far heating mode where the heaters is located furthest from the condenser.

  • PDF

양파(Allium cepa L)의 RAPD 분석조건 최적화에 관한 연구 (Optimization of RAPD-PCR Conditions for Onions, Allium cepa L.)

  • 정순재;양보경;김익수;박선희;서전규;남재성;김현경;김도훈
    • 생명과학회지
    • /
    • 제10권2호
    • /
    • pp.182-187
    • /
    • 2000
  • The optimized RAPD-PCR conditions, which can be utilized as a basic information for the analysis of the genetic characteristics were investigated with four onion varieties, named Changryungdaego, Yeoeuijuhwang, Yakwangju, and Dabonghwang using Operon primers, OPR01 (TGCGGGTCCT) and OPZ20 (ACTTTGGCGG). We tested several concentrations of DNA, primer, and MgCl2, annealing temperature, number of PCR cycle, and presence/absence of pre-heating time at the begining of PCR reation in the 25${mu}ell$ volume. The best RAPD profiles were obtained using 50ng of DNA, 5mM of primer, 1.5mM of MgCl2, 45$^{\circ}C$ of annealing temperature and an absence of pre-heating time. An establishment of the stable and reproducible RAPD-PCR conditions are expected to be useful for the subsequent RAPD-related investigation, such as genetic characterization of the onion strains, re-establishment of phylogenetic relationships and development of new varieties.

  • PDF

다중 펄스 방식에 의한 고성능 오존발생 제어장치 개발 (Development of High Performance Ozone Generating Controller)

  • 이홍희;김형준
    • 대한전기학회논문지:시스템및제어부문D
    • /
    • 제52권5호
    • /
    • pp.226-226
    • /
    • 2003
  • When an excessive voltage is applied to the discharge gap in ozone generator, the discharge room temperature becomes higher. As is well own, the efficiency of the ozone generation is deteriorated by the excessively hot temperature because of the decomposition reaction. In this paper, the simple small capacity ozone generating controller has been introduced, which provides effective and stable silent discharge characteristics over wide range input power. The proposed power controller has two important advantages, which imply that the production rate of ozone can be controlled linearly according to the delivered power and the surplus energy is recovered to the source. The experimental results are given to verify the performance of the pre proposed controller.

다중 펄스 방식에 의한 고성능 오존발생 제어장치 개발 (Development of High Performance Ozone Generating Controller)

  • 이홍희;김형준
    • 대한전기학회논문지:전기물성ㆍ응용부문C
    • /
    • 제52권5호
    • /
    • pp.226-230
    • /
    • 2003
  • When an excessive voltage is applied to the discharge gap in ozone generator, the discharge room temperature becomes higher. As is well own, the efficiency of the ozone generation is deteriorated by the excessively hot temperature because of the decomposition reaction. In this paper, the simple small capacity ozone generating controller has been introduced, which provides effective and stable silent discharge characteristics over wide range input power. The proposed power controller has two important advantages, which imply that the production rate of ozone can be controlled linearly according to the delivered power and the surplus energy is recovered to the source. The experimental results are given to verify the performance of the pre proposed controller.

APCVD에 의란 BPSG 막질특성에 관란 연구 (A Study on Characteristics of Borophosphosilicate Gloss deposited by At.ospheri, Pressure Chemical Vapor Deposition)

  • 김의송;이철진;류지효;송성해
    • 대한전기학회:학술대회논문집
    • /
    • 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(I)
    • /
    • pp.561-564
    • /
    • 1987
  • The deposition and reflow properties or BPSG film deposited by APCVD was characterized by variation of each process parameter. As deposition temperature is increased higher, deposition rate is decreased. Maximum deposition rate of BPSG film is obtained in higher 02/Hyride ratio than CVD Oxide or PSG. BPSG film shows stable dielectric properties and we obtained good planarization effect at lower reflow temperature in case of BPSG film than PSG film.

  • PDF