• 제목/요약/키워드: M40J

검색결과 979건 처리시간 0.026초

40채널 SQUID 시스템의 설계 (Design of a 40 channel SQUID system)

  • 이용호;김진목;권혁찬;임청무;이상길;박용기;박종철;이동훈;신진교;안창범;박민석;허용;흥종배
    • 대한의용생체공학회:학술대회논문집
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    • 대한의용생체공학회 1998년도 추계학술대회
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    • pp.191-192
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    • 1998
  • We report on the design of a low-noise 40 channel SQUID system for biomagnetism. We used low-noise SQUID sensor with the pickup coil integrated on the same wafer as the SQUID. The SQUID electronics were simplified by increasing the voltage output of the SQUID. The SQUID insert was designed to have low thermal load, minimizing the liquid helium loss. The digital signal processing provides versatile analysis tools and the software is based on the object-oriented programming. For the effective localization of the source location, solutions of the inverse problems based on the lead-field and the simulated anneal ins were studied.

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Development of state-of-the-art detectors for X-ray astronomy

  • Lee, Sang Jun;Adams, J.S.;Audley, H.E.;Bandler, S.R.;Betancourt-Martinez, G.L.;Chervenak, J.A.;Eckart, M.E.;Finkbeiner, F.M.;Kelley, R.L.;Kilbourne, C.A.;Porter, F.S.;Sadleir, J.E.;Smith, S.J.;Wassell, E.J.
    • 천문학회보
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    • 제40권1호
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    • pp.53.3-54
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    • 2015
  • We are developing large arrays of X-ray microcalorimeters for applications in X-ray astronomy. X-ray microcalorimeters can detect the energy of X-rays with extremely high resolution. High-resolution Imaging spectroscopy enabled by these arrays will allow us to study the hot and energetic nature of the Universe through the detection of X-rays from astronomical objects such as neutron stars or black holes. I will introduce the state-of-the-art X-ray microcalorimeters being developed at NASA/GSFC and the future X-ray observatory missions based on microcalorimeters.

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A parametric study of optimum tall piers for railway bridge viaducts

  • Martinez-Martin, Francisco J.;Gonzalez-Vidosa, Fernando;Hospitaler, Antonio;Yepes, Victor
    • Structural Engineering and Mechanics
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    • 제45권6호
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    • pp.723-740
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    • 2013
  • This paper presents a parametric study of reinforced concrete bridge tall piers with hollow, rectangular sections. Such piers are typically used in railway construction of prestressed concrete viaducts. Twenty one different piers have been studied with seven column heights of 40, 50, 60, 70, 80, 90 and 100 m and three types of 10-span continuous viaducts, whose main span lengths are 40, 50 and 60 m. The piers studied are intermediate columns placed in the middle of the viaducts. The total number of optimization design variables varies from 139 for piers with column height of 40 m to 307 for piers with column height of 100 m. Further, the results presented are of much value for the preliminary design of the piers of prestressed concrete viaducts of high speed railway lines.

The effect of laser energy on the preparation of iron oxide by a pulsed laser ablation in ethanol

  • Maneeratanasarn, P.;Khai, T.V.;Choi, B.G.;Shim, K.B.
    • 한국결정성장학회지
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    • 제22권3호
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    • pp.134-138
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    • 2012
  • Recently the preparation magnetic nanoparticles by a pulsed laser ablation in liquid has gained much attention because it is easy to control experimental parameters. Iron oxide magnetic nanoparticles have been prepared by a pulsed laser ablation of ${\alpha}-Fe_2O_3$ target in ethanol at different magnitude of laser energy of 1, 20, 40 and 80 mJ/pulse. It revealed that particle size increases with increasing laser energy. It could be concluded that 40 mJ/pulse is an optimum laser energy for the preparation of iron oxide nanoparticles with uniform size distribution. The nanoparticles are homogeneously dispersed in ethanol and their stability maintained for several months.

A 40fJ/c-s 1 V 10 bit SAR ADC with Dual Sampling Capacitive DAC Topology

  • Kim, Bin-Hee;Yan, Long;Yoo, Jerald;Yoo, Hoi-Jun
    • JSTS:Journal of Semiconductor Technology and Science
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    • 제11권1호
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    • pp.23-32
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    • 2011
  • A 40 fJ/c-s, 1 V, 10-bit SAR ADC is presented for energy constrained wearable body sensor network application. The proposed 10-bit dual sampling capacitive DAC topology reduces switching energy by 62% compared with 10-bit conventional SAR ADC. Also, it is more robust to capacitor mismatch than the conventional architecture due to its cancelling effect of each capacitive DAC. The proposed SAR ADC is fabricated in 0.18 ${\mu}m$ 1P6M CMOS technology and occupies 1.17 $mm^2$ including pads. It dissipates only 1.1 ${\mu}W$ with 1 V supply voltage while operating at 100 kS/s.

Reduction of Ammonia Emissions by Compost Biofilter from the Agitated Bed Composting of Hog Manure

  • J. H. Hong;Park, K. J.;Kim, J. Y.
    • 한국농공학회지
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    • 제44권7호
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    • pp.46-52
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    • 2002
  • Manure compost biofilter for reducing ammonia emissions at the active stage of a semi air tight and agitated bed composting of hog manure amended with sawdust were evaluated in the practical composting plant(75 m 5 m $\times$1.4 m deep). During 55 days of composting and biofiltration process, the manure compost biofilter had a ammonia reduction of 91 to 98%. Results showed that the active stage of composting maintained temperatures between 40 and 7$0^{\circ}C$ and fluctuated greatly the ammonia concentrations between 100 and 300 ppm. Ammonia concentrations in manure compost biofiltration reached within a moderate range (2-18 ppm).

MEMS 고체 추진제 추력기의 점화 시스템 개발 (Development of Ignition System for MEMS Solid Propellant Thruster)

  • 이종광;박종익;권세진
    • 한국추진공학회:학술대회논문집
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    • 한국추진공학회 2007년도 제28회 춘계학술대회논문집
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    • pp.91-94
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    • 2007
  • 마이크로 고체 추진제 추력기의 점화 시스템의 제작 및 점화 실험에 관한 연구 결과를 기술하겠다. 유리 박막 마이크로 백금 점화기는 일반적인 금속 박리 공정과 감광 유리 제작 공정을 이용하여 제작되었다. 백금 층의 두께는 $2000{\AA}$, 점화기 패턴의 폭은 $40{\mu}m$ 였다. 제작된 유리 박막의 두께는 $15{\mu}m$, 유리 박막의 지름은 1 mm 였다. HTPB/AP 추진제를 이용하여 점화 실험을 수행하였다. 12 V의 전압을 사용한 경우, 점화 지연 시간은 1.6 s 였으며 이 때의 점화 에너지는 1.4 J로 측정되었다.

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