• 제목/요약/키워드: F-V characteristics

검색결과 643건 처리시간 0.03초

LiF ( Mg , Cu , P ) 단결정의 TSD 특성에 관한 연구 (Study on TSD Characteristics of LiF ( Mg , Cu , P ) Single Crystal)

  • 도시홍
    • 수산해양기술연구
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    • 제26권1호
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    • pp.8-13
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    • 1990
  • LiF(Mg, Cu, P) 단결정의 미시적 이완매개변수와 유전손실 등을 구하기 위하여 TSD glow곡선을 측정하고, 측정된 glow곡선을 초기상승법, 가열율법 및 전면적법으로 해석하였다. 쌍극자의 이완시간 $\tau$, pre-exponential인자 $\tau$하(o) 및 활성화에너지E는 각각 12.19S, 1.97$\times$10 상(-12)S 및 0.55eV이었다. 또한 TSD glow곡선을 사용하여 온도영역 300k~340k 사이에서 구한 LiF(Mg, Cu, P)단 결정의 tan$\delta$값은 약 3$\times$10 상(-2)이었다.

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Electrical and Optical Characteristics in Organic Electroluminescent Devices with Different Materials for Electron Injection

  • Cho, Min-Jeong;Park, wan-Ji;Lim, Min-Su;Cheol-Hyun park;Jeon-Gu lee;Lim, Kee-Joe;Park, Soo-Gil;Kim, Hyun-Hoo
    • KIEE International Transactions on Electrophysics and Applications
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    • 제11C권2호
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    • pp.37-41
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    • 2001
  • In this study, organic electroluminescent devices with the ITO/TPD/Alq$_3$/cathode structure, using various materials of Al, Mg:Ag, Al:Li, MgF$_2$/Al, and LiF/Al as cathodes, were fabricated. We investigated the electrical and optical properties of the devices as follow: current density-voltage(J-V), luminance-voltage(L-V) and luminous efficiency-voltage curves. The bilayer cathodes with LiF/Al and MgF$_2$/Al exhibited better device performance than the other cathodes. It is considered that the improved performance of the organic electroluminescent devices is attributable to the lowering of driving voltage caused by the enhanced electron injection. The alkaline-earth fluorides are desirable materials to improve the performance of the EL devices with the Al cathode, and high luminous efficiency was achieved.

LiF:Mg,Cu,Na,Si TL 소자의 선량계적 특성 (Dosimetric Properties of LiF:Mg,Cu,Na,Si TL pellets)

  • 남영미;김장렬;장시영
    • Journal of Radiation Protection and Research
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    • 제26권1호
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    • pp.7-12
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    • 2001
  • 최근 개발된 방사선량 측정용 LiF:Mg,Cu,Na,Si TL 소자의 글로우 곡선, 방출스펙트럼, 광자에 대한 선량의존성, 에너지의존성 및 페이팅 등과 같은 물리적 및 선량계적 특성들을 연구하였다. LiF:Mg,Cu,Na,Si TL 소자는 LiF:Mg,Cu,Na,Si TL 분말에 압력을 가한 후 소결하는 방법으로 제조되었다. 방사선에 대한 특성을 알아보기 위하여 광자선 조사는 한국원자력연구소의 X선 발생 장치 및 $^{137}Cs$ ${\gamma}$선 원격조사장치를 이용하였으며, 사용된 광자선 에너지 범위는 20-662keV, 선량 범위는 $10^{-6}-10^{-2}\;Gy$이었다. 글로우 곡선은 수동형의 TLD 판독장치 (System 310, Teledyne)로 질소를 흘리면서 선형적인 가열률로 측정하였으며, TL 강도는 글로우 곡선을 전체 적분한 면적으로 평가하였다. $5^{\circ}C\;s^{-1}$의 선형적인 가열률로 측정한 글로우 곡선은 5개의 피크들로 분리되었으며, $234^{\circ}C$에 나타나는 주피크의 활성화에너지는 2.34 eV, 진동수인자는 $1.00{\times}10^{23}$이고, 방출스펙트럼은 410nm를 중심으로한 단일한 분포로 나타났다. 선량의존성은 100Gy 이상까지 선형성을 나타내었으며, $^{137}Cs$에 대한 저에너지 광자의 상대적인 에너지 반응값은 20% 범위 이내였다. 또한 실온에서 1년간 보관하였을 때, 시간경과에 따른 TL 감도의 감소가 거의 없는 좋은 페이딩 특성을 보였다.

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64채널 DROS 심자도 시스템을 위한 검출 회로의 잡음 특성 (Noise Characteristics of Readout Electronics for 64-Channel DROS Magnetocardiography System)

  • 김진목;김기담;이용호;유권규;김기웅;권혁찬
    • Progress in Superconductivity
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    • 제7권1호
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    • pp.46-51
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    • 2005
  • We have developed control electronics to operate flux-locked loop (FLL), and analog signal filters to process FLL outputs for 64-channel Double Relaxation Oscillation SQUID (DROS) magnetocardiography (MCG) system. Control electronics consisting of a preamplifier, an integrator, and a feedback, is compact and low-cost due to larger swing voltage and flux-to-voltage transfer coefficients of DROS than those of dc SQUIDs. Analog signal filter (ASF) serially chained with a high-pass filter having a cut-off frequency of 0.1 Hz, an amplifier having a gain of 100, a low-pass filter of 100 Hz, and a notch filter of 60 Hz makes FLL output suitable for MCG. The noise of a preamplifier in FLL control electronics is $7\;nV/{\surd}\;Hz$ at 1 Hz, $1.5\;nV/{\surd}\;Hz$ at 100 Hz that contributes $6\;fT/{\surd}\;Hz$ at 1 Hz, $1.3\;fT/{\surd}\;Hz$ at 100 Hz in readout electronics, and the noise of ASF electronics is $150\;{\mu}V/{\surd}\;Hz$ equivalent to $0.13\;fT/{\surd}\;Hz$ within the range of $1{\sim}100\;Hz$. When DROSs are connected to readout electronics inside a magnetically shielded room, the noise of 64-channel DROS system is $10\;fT/{\surd}\;Hz$ at 1 Hz, $5\;fT/{\surd}\;Hz$ at 100 Hz on the average, low enough to measure human MCG.

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AlGaAs/InGaAs/GaAs Power PHEMT 설계.제작 (Design and fabrications of AlGaAs/InGaAs/GaAs Power PHEMT)

  • 이응호;조승기;윤용순;이일형;이진구
    • 대한전자공학회:학술대회논문집
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    • 대한전자공학회 2000년도 하계종합학술대회 논문집(2)
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    • pp.12-15
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    • 2000
  • In this paper, we have fabricated the PHEMT's with AlGaAs/InGaAs/GaAs and measured characteristics of DC and frequencies. The PHEMT's has a 0.35$\mu\textrm{m}$ gate length, gate width of 60$\mu\textrm{m}$ and 80$\mu\textrm{m}$, and fingers of 2 and 4. From the measurements results for the 60$\mu\textrm{m}$ ${\times}$ 2 PHEMT's, we obtained 1.2V of Vk, -3.5V of Vp, 46mA of Idss, 221mS/mmof gm, and 3.6dB of S$\sub$21/ gain, 45GHz of f$\sub$T,/ 100GHz of fmax. And, in case of 80$\mu\textrm{m}$ ${\times}$ 4 PHEMT's, we obtained 1.2V of Vk, -4.5V of Vp, 125mA of Idss, 198mS/mm of gm, and 2.0dB of S$\sub$21/ gain. 44GHz of f$\sub$T/, 70GHz of fmax at 35GHz frequency. Also, MAG are decreased as a number of finger are Increased.

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Evaluation of Inflammation Parameters in Philadelphia Negative Chronic Myeloproliferative Neoplasia Patients

  • Hacibekiroglu, Tuba;Akinci, Sema;Basturk, Abdulkadir;inal, Besime;Guney, Tekin;Bakanay, Sule Mine;Dilek, Imdat
    • Asian Pacific Journal of Cancer Prevention
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    • 제16권13호
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    • pp.5159-5162
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    • 2015
  • Background: Chronic myeloproliferative diseases are clonal stem cell diseases which occur as a result of uncontrollable growth and reproduction of hematopoietic stem cells, which are the myeloid series source in bone marrow. Recent studies have suggested that chronic inflammation can be a triggering factor in the clonal change in chronic myeloproliferative neoplasia (CMPN). In our study, we evaluated the existence of a chronic inflammation process in our Philadelphia negative (Ph-)CMPN patients using inflammation parameters in combination with demographic, laboratory and clinical characteristics of the patients. Materials and Methods: Demographic characteristics, clinical and laboratorial data, and thrombosis histories of 99 Ph-CMPN patients, who were diagnosed at our outpatient clinic of hematology in accordance with WHO 2008 criteria, were analyzed retrospectively,with 80 healthy individuals of matching gender and age included as controls. Complete blood counts, sedimentation, C reactive protein (CRP), JAK V617F gene mutations, abdomen ultrasound images and previous thrombosis histories of these patients were retrospectively analyzed. Results: Ph-CMPN and healthy control groups included 99 and 80 cases, respectively. PV, ET and MF diagnoses of patients were 43 (%43.4), 44 (44.4%) and 12 (12.1%), respectively. JAK V617F gene mutation was found to be positive in 64 (71.1%) of all cases and in 27(65.8%), 32 (82%), 5 (50%) of the cases in PV, ET and PMF groups, respectively. Thrombosis was determined as 12 (12%) in the entire group, 12.5% in the JAK V617F negative and 15.3% in the positive patients, with no statistical significance (p=0.758). No significant difference was observed between patients with and without previous thrombosis history in respect to hemogram parameters, sedimentation and CRP (p>0.05), neutrophil to lymphocyte ratio (NLR), erythrocyte distribution width (RDW), mean platelet volume (MPV) and sedimentation levels of the patient.

NEW OPTICAL TECHNIQUES FOR THE 'STRUVE' SPACE ASTROMETRIC PROJECT

  • YERSHOV V. N.;TSUKANOVA G. I.;STARICHENKOVA V. D.;ZAKHARENKOV G. F.;GRIAZNOV G. M.
    • 천문학회지
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    • 제29권spc1호
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    • pp.425-426
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    • 1996
  • A few optical schemes for the future Russian astrometric satellite ('Struve') are discussed. New optical materials and techniques developed at the Vavilov State Optical Institute are planned to be used for the on-board telescopes. Optical characteristics of the reflecting Schmidt and a three - mirror scheme for the on-board telescopes are compared.

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1/f Noise Characteristics of Sub-100 nm MOS Transistors

  • Lee, Jeong-Hyun;Kim, Sang-Yun;Cho, Il-Hyun;Hwang, Sung-Bo;Lee, Jong-Ho
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제6권1호
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    • pp.38-42
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    • 2006
  • We report 1/f noise PSD(Power Spectrum Density) of sub-100 nm MOSFETs as a function of various parameters such as HCS (Hot Carrier Stress), bias condition, temperature, device size and types of MOSFETs. The noise spectra of sub-100 nm devices showed Lorentzian-like noise spectra. We could check roughly the position of a dominant noise source by changing $V_{DS}$. With increasing measurement temperature, the 1/f noise PSD of 50 nm PMOS device decreases, but there is no decrease in the noise of NMOS device. RTN (Random Telegraph Noise) was measured from the device that shows clearly a Lorentzian-like noise spectrum in 1/f noise spectrum.

f-$\theta$렌즈 표면형상오차와 광학적 성능과의 연관성 분석 (An Analysis of the Relationship between Surface Profile Error of f-$\theta$Lens and Optical Performance)

  • 김동식;이인용;김형채
    • 한국정밀공학회지
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    • 제18권2호
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    • pp.90-95
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    • 2001
  • f-$\theta$len is one of the important parts in Laser Scanning Unit because it affects on the optical performance of Laser Scanning Unit dominantly. It is necessary to find out the relationship between the surface profile error of f-$\theta$lens and the beam profile focusing on the Organic Photo Conductive drum in order to analysis the beam profile problems such as appearance of side lobe and expansion of center lobe. In this research, a simulation process which relates the surface profile characteristics to the beam profile has been developed by CODE V. The simulated beam profile also have been compared with the measurement results.

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