• Title/Summary/Keyword: Spikes

Search Result 362, Processing Time 0.028 seconds

ALGORITHM OF REVISED-OTFTOOL

  • Chung Eun-Jung;Kim Hyor-Young;Rhee Myung-Hyun
    • Journal of Astronomy and Space Sciences
    • /
    • v.23 no.3
    • /
    • pp.269-288
    • /
    • 2006
  • We revised the OTFTOOL which was developed in Five College Radio Astronomy Observatory (FCRAO) for the On-The-Fly (OTF) observation. Besides the improvement of data resampling function of conventional OTFTOOL, we added a new SELF referencing mode and data pre-reduction function. Since OTF observation data have a large redundancy, we can choose and use only good quality samples excluding bad samples. Sorting out the bad samples is based on the floating level, rms level, antenna trajectory, elevation, $T_{sys}$, and number of samples. And, spikes are also removed. Referencing method can be chosen between CLASSICAL mode in which the references are taken from the OFFs observation and ELLIPSOIDAL mode in which the references are taken from the inner source free region (this is named as SELF reference). Baseline is subtracted with the source free channel windows and the baseline order chosen by the user. Passing through these procedures, the raw OTF data will be an FITS datacube. The revised-OTFTOOL maximizes the advantages of OTF observation by sorting out the bad samples in the earliest stage. And the new self-referencing method, the ELLIPSOIDAL mode, is very powerful to reduce the data. Moreover since it is possible to see the datacube at once without moving them into other data reduction programs, it is very useful and convenient to check whether the data resampling works well or not. We expect that the revised-OTFTOOL can be applied to the facilities of the OTF observation like SRAO, NRAO, and FCRAO.

Blockade of Intrinsic Oscillatory Activity of Cerebellar Purkinje Cells by Apamin and Nickel

  • Seo, Wha-Sook;Strahlendorf, Jean-C.;Strahlendorf, Howard-K.
    • The Korean Journal of Physiology and Pharmacology
    • /
    • v.1 no.5
    • /
    • pp.477-484
    • /
    • 1997
  • Intracellular recordings of oscillatory firing (bursting activity) were obtained from Purkinje cells (PCs) in rat cerebellar slices. Apamin inhibited post-burst hyperpolarizations (PBHs) progressively and finally terminated oscillatory firing activity of PCs. Apamin did not affect the amplitude or duration of the after-hyperpolarization (AHP) between spikes within the burst. In the voltage clamp mode, apamin shifted the whole-cell, quasi-steady state I/V relationship in an inward direction and abolished the zero slope resistance (ZSR) region by blocking outward current. Nickel ($Ni^{2+}$) terminated oscillatory activity and also abolished the ZSR region. However, $Ni^{2+}$ did not have progressive blocking action on the post-burst hyperpolarization before it blocked oscillatory activity. $Ni^{2+}$ blocked an inward current at potentials positive to approximately -65 mV, which was responsible for the ZSR region and outward current at more negative potentials. These data indicated that oscillatory activity of PCs is sustained by a balance between a slow $Ni^{2+}$-sensitive inward current and an apamin-sensitive outward current in the region of ZSR of the whole-cell I/V curve.

  • PDF

DISSOLUTION AND BURNUP DETERMINATION OF IRRADIATED U-Zr ALLOY NUCLEAR FUEL BY CHEMICAL METHODS

  • Kim, Jung-Suk;Jeon, Young-Shin;Park, Soon-Dal;Song, Byung-Chul;Han, Sun-Ho;Kim, Jong-Goo
    • Nuclear Engineering and Technology
    • /
    • v.38 no.3
    • /
    • pp.301-310
    • /
    • 2006
  • Destructive methods were used for the burnup determination of U-Zr alloy nuclear fuel irradiated in the High-flux Advanced Neutron Application Reactor (HANARO) at KAERI. The dissolution rate of unirradiated U-Zr alloy fuel in $HNO_3$/HF mixtures was investigated for the experimental conditions of a different temperature, and initial concentrations of HF and $HNO_3$. The irradiated U-Zr alloy fuel specimen was dissolved in a mixed acid condition of 3 M HNO3 and 1 M HF at $90^{\circ}C$ for 8 hours under reflux. The total burnup was determined from measurement of the Nd isotope burnup monitors. The method includes U, Pu, $^{148}Nd,\;^P{145}Nd+^{146}Nd,\;^{144}Nd+^{143}Nd$ and total Nd isotopes determination by the isotope dilution mass spectrometric method (IDMS) using triple spikes $(^{233}U,\;^{242}Pu\;and\;^{150}Nd)$. The effective fission yield was calculated from the weighted fission yields averaged over the irradiation period. The results are compared with that obtained by the destructive -spectrometric measurement of the $^{137}Cs$ monitor.

Petrochemical Characteristics and Review on Petrogenesis on Cretaceous to Tertiary Volcanic Rocks in the Kyongsang Basin (경상분지 백악기~제3기 화산암류의 암석화학적 특징과 암석 성인 고찰)

  • Sung, Jong-Gyu;Kim, Jin-Seop
    • The Journal of the Petrological Society of Korea
    • /
    • v.21 no.2
    • /
    • pp.217-233
    • /
    • 2012
  • Major elements abundances of Cretaceous to Tertiary volcanic rocks in Kyongsang basin are similar with Southern Volcanic Zone (SVZ) in Andes. Sr, K, Rb, $Ba{\pm}Th$ abundances, which have low ionic charge, are selectively fertile, on the other hand Ta, Nb, Ce, P, Zr, Hf, Sm, Ti, Y, Yb, Sc, Cr abundances are low. K, Sr, Th show characteristic spikes and Nb show remarkable trough on trace elements spider diagram. Trace elements abundances are higher than that of Andes which is supposed to mantle sources of Kyongsang basin volcanic rocks are produced lower degree of partial melting than SVZ in Andes.

A EMG Signal Processing Algorithm for SMUAP Pattern Classification (SMUAP의 패턴분류를 위한 근 신호처리 알고리듬)

  • Lee, Jin;Jo, Il-Jun;Byun, Youn-Shik;Hong, Woan-Hue;Kim, Sung-Hwan
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.26 no.7
    • /
    • pp.106-111
    • /
    • 1989
  • A new EMG signal processing algorithm for SMUAP pattern classification is proposed. It checks the combination and regularity of ISI using a spike counter as a decision making routine, and performs SMUAP waveform alignment in frequency domain and selects spikes through FIR filtering. As a result, with the EMG signals recorded during 5 seconds at 10-50% MVC force level, the SMUAP ranged from five to nine units were classified and identification rate is greater than 55 percent using a concentric needle electrode. In the IBM PC/AT the processing time typically required 2 minutes.

  • PDF

Simulation of IGBT Dimmer Using EMTDC (EMTDC를 이용한 IGBT Dimmer 시뮬레이션)

  • Kim, Bo-Kyong;Park, Min-Won;Seong, Ki-Chul;Yu, In-Keun
    • Proceedings of the KIEE Conference
    • /
    • 2001.05a
    • /
    • pp.194-196
    • /
    • 2001
  • Light dimming is based on adjusting the voltage which gets to the lamp. Light dimming has been possible for many decades by using adjustable power resistors and adjustable transformers. The power electronics have proceeded quietly since 1960. Between 1960-1970 thyristors and triacs came to market. Using those components it was quite easy to make small and inexpensive light dimmers which have goof efficiency. This type of electronic light dimmers became available after 1970 and are nowadays used in very many locations like homes, restaurants, conference rooms and in stage lighting. But the problem of thyristor dimmer have been that it has poor efficiency and voltage drop. Recently IGBT(Insulated Gate Bipolar Transistor) control is a new way to do light dimming for improving this problems. IGBT dimmer has many other advantages over traditional thyristor dimmer there are no huge current spikes and EMI caused by turn on Using IGBT it is possible to make the turn-off rate relatively slot to achieve quite operations in terms of EMI and acoustical or incandescent lamp filament noise. For the development of IGBT dimmer. This paper shows the effects of IGBT dimmer compared with thyristor dimmer through a simulation using EMTDC.

  • PDF

FVF-Based Low-Dropout Voltage Regulator with Fast Charging/Discharging Paths for Fast Line and Load Regulation

  • Hinojo, Jose Maria;Lujan-Martinez, Clara;Torralba, Antonio;Ramirez-Angulo, Jaime
    • ETRI Journal
    • /
    • v.39 no.3
    • /
    • pp.373-382
    • /
    • 2017
  • A new internally compensated low drop-out voltage regulator based on the cascoded flipped voltage follower is presented in this paper. Adaptive biasing current and fast charging/discharging paths have been added to rapidly charge and discharge the parasitic capacitance of the pass transistor gate, thus improving the transient response. The proposed regulator was designed with standard 65-nm CMOS technology. Measurements show load and line regulations of $433.80{\mu}V/mA$ and 5.61 mV/V, respectively. Furthermore, the output voltage spikes are kept under 76 mV for 0.1 mA to 100 mA load variations and 0.9 V to 1.2 V line variations with rise and fall times of $1{\mu}s$. The total current consumption is $17.88{\mu}V/mA$ (for a 0.9 V supply voltage).

Correlations between Zirconium Isotopes and Burnup Parameters in PWR Spent Nuclear Fuels

  • Kim, Jung-Suk;Chun, Young-Shin;Lee, Chang heon;Kim, Won-Ho;Eom, Tae-Yun
    • Proceedings of the Korean Nuclear Society Conference
    • /
    • 1998.05b
    • /
    • pp.551-556
    • /
    • 1998
  • The correlation of isotope composition of Zr with the turnup and some heavy isotopes in PWR uranium dioxide fuel has been investigated. The total and partial ($^{235}$ U) burnup were determined by $^{148Nd}$ and by U and Pu mass spectrometric method, respectively. After separating Zr from the fuel samples, its isotope composition was measured by mass spectrometry. In addition, the quantities of the U and Pu in the spent fuel were determined by isotope di lution mass spectrometric method using $^{233}$ U and $^{242}$ Pu as spikes. The content of some heavy isotopes, $^{235}$ U, $^{239}$ Pu and $^{241}$ Pu, and the Pu Contribution to total turnup were expressed by the correlation with Zr isotope ratios, $^{91}$ Zr/$^{96}$ Zr and $^{93}$ Zr/$^{96}$ Zr The correlations by isotope compositions measured were compared wi th those calculated from ORIGEN2 code.

  • PDF

Experimental calibration of forward and inverse neural networks for rotary type magnetorheological damper

  • Bhowmik, Subrata;Weber, Felix;Hogsberg, Jan
    • Structural Engineering and Mechanics
    • /
    • v.46 no.5
    • /
    • pp.673-693
    • /
    • 2013
  • This paper presents a systematic design and training procedure for the feed-forward back-propagation neural network (NN) modeling of both forward and inverse behavior of a rotary magnetorheological (MR) damper based on experimental data. For the forward damper model, with damper force as output, an optimization procedure demonstrates accurate training of the NN architecture with only current and velocity as input states. For the inverse damper model, with current as output, the absolute value of velocity and force are used as input states to avoid negative current spikes when tracking a desired damper force. The forward and inverse damper models are trained and validated experimentally, combining a limited number of harmonic displacement records, and constant and half-sinusoidal current records. In general the validation shows accurate results for both forward and inverse damper models, where the observed modeling errors for the inverse model can be related to knocking effects in the measured force due to the bearing plays between hydraulic piston and MR damper rod. Finally, the validated models are used to emulate pure viscous damping. Comparison of numerical and experimental results demonstrates good agreement in the post-yield region of the MR damper, while the main error of the inverse NN occurs in the pre-yield region where the inverse NN overestimates the current to track the desired viscous force.

The Influence of Water Depth and Melt Composition on a Steam Explosion in Severe Accidents in a Nuclear Reactor (원자로에서 중대사고시 냉각수의 수심과 용융물 성분이 증기폭발에 미치는 영향)

  • Kim, Jong-Hwan;Park, Ik-Kyu;Hong, Seong-Wan;Min, Beong-Tae;Song, Jin-Ho;Kim, Hee-Dong
    • Proceedings of the KSME Conference
    • /
    • 2003.11a
    • /
    • pp.414-419
    • /
    • 2003
  • In the recent TROI experiments, melts of zirconia and two different compositions of corium were used to observe the occurrence of a steam explosion when it came into contact with water at two different depths. The compositions of the corium were 70 : 30 and 80 : 20 in weight percent of $UO_{2}$ and $ZrO_{2}$, and the mass of the corium was about 10kg. The depth of water in the interaction vessel was 67cm and 130cm. A steam explosion did not occur in the interaction between 80 : 20 corium melt and water at 130cm depth, while steam spikes were observed in the interactions between corium melts of two different compositions and water at 67cm depth. A strong steam explosion occurred in the interaction between 5.43kg of zirconia melt and water at 67cm depth. This fact shows that the explosivity of zirconia is much greater than that of corium.

  • PDF