• Title/Summary/Keyword: single pulse

검색결과 828건 처리시간 0.022초

돼지에 있어서 4-세포기 분할구의 체외발생능과 난모세포의 활성화에 미치는 전기자극의 효과 (Effects of Electrostimulation on In Vitro Development Ability of Single 4-cell Blastomeres and Oocyte Activation in Porcine)

  • 이상진;;정순영;박흠대
    • 한국가축번식학회지
    • /
    • 제20권3호
    • /
    • pp.239-250
    • /
    • 1996
  • The objective of the present experiments were to determine whether micromanipulative and electro-stimulation conditions for blastomere survival overlapped those for oocyte activation in porcine. Eggs selected for in vitro development potential of blastomeres isolated from 4-cell embryos and oocyte activation by electrostimulation were equilibrated for 5~10 min, in 0.3M sucrose solution containing 7.5$\mu\textrm{g}$/ml cytochalasin B, and then electrostimulated for 30$\mu$sec using one pulse of 100, 120, 150 or 180 volts DC with electrodes 0.2mm apart. Single blastomeres were inserted into empty zona pellucida prior to electrostimulaticn. Then they were cultured in 20${mu}ell$ drops of fresh BECM to observe their developmental ability in vitro in a humidified incubat or at 38.5$^{\circ}C$. The results obtained from these experiments are as follows : 1. When one pulse of 100, 120, 150 or 180 volts DC for 30$\mu$sec were applied to porcine oocytes having the slit formed on zona pellucida for activation, activation rates were 65.1, 66.7, 70.7 and 91.7%, respectively. Higher activation rate was observed in 180V. 2. Infact oocytes incubated for 30 min, in 0.3M sucrose solution after electrostimulation were significantally different from control group with increasing of voltages(p<0.05). When voltages used for electrostimulation were increased, activation rates of oocytes were improved in all treatment groups. 3. When zona punctured-oocytes were only electrostimulated, or incubated in 0.3M sucrose solution for 30 min. after electrostimulation at 180 volt DC, activation rates were 90.5 and 95.5%, respectively. And activation rates of zona punctured-oocytes were significantly different from the groups for which zona pellucida was not punctured(P<0.05). 4. When single blastomeres form 4-cell transferred into empty zona pellucida were incubated for 0, 15 and 30 min. in 0.3M sucrose solution after electrostimulation using one pulse of 180 volt DC for 30 $\mu$sec, developmental rates of electrostimulated-single blastomeres to blastocyst were 72.5, 59.0 and 51.2%, respectively, and the ratio of control group developed to blastocyst were 80.0%. 5. The average cell number in electrostimulated-blastomeres developed to blastocyst were 7.9~10.8, and reduced than the cell number in diploid control ; Also cell number decreased with increasing of voltages. The results of these experiments indicate that the optimal condition for achieving in vitro developmental ability of single 4-cell blastomeres and oocyte activatin is 1 pulse, duration 30 $\mu$sec. in 180 volt, and incubation of blastomeres and oocytes in 0.3M sucrose solution after electrostimulation was not significantally different from another treatment groups. The results also show that this condition is suitable for nuclear transplantation using porcine eggs.

  • PDF

5단계 가압 맥파측정에 의한 연령별 혈관 경화도 분석 (Analysis of Arterial Stiffness by Age Using Pulse Waveform Measurement of 5-levels Graded Pressure)

  • 권선민;강희정;임윤경;이용흠
    • Korean Journal of Acupuncture
    • /
    • 제27권2호
    • /
    • pp.107-120
    • /
    • 2010
  • Objectives : The aim of this study is to measure pulse waveforms by applying 5-level graded pressure, and selecting optimum pulse waveforms. Also to proposing the possibility of using AW(Area of the 1/3 upper height of h1) rate in respect to AT(Total Area) for risk assessment of hypertension or arteriosclerosis is another aim of the study. Methods : Pulse waveforms of normotensive were measured by 5-level graded pressure. The pulse waveforms well reflecting properties of blood vessel(having the largest h1) were selected for optimum pulse waveforms. Various parameters(h-parameter, t-parameter, and others) of optimum pulse waveforms were analyzed. AIx(Augmentation index) was calculated by height-parameters to assess arterial stiffness. The area rate of the 1/3 upper height for h1 in respect to total area was analyzed according to aging. Results : According to aging 1. in height-parameter, h2 and h3 were increased but h5 was decreased. 2. In time-parameter, t2, t3, and t5 were getting short. 3. Area of systolic period was increased, and that of diastolic period decreased. 4. AIx rose by aging. 5. AW was significantly increased despite no changes in AT. Conclusions : By analyzing optimum pulse waveforms of 5-level graded pressure method, we could complement weakness of single graded pressure method. Also, possibility of applying the AW rate to risk assessment of hypertension or arteriosclerosis was confirmed in normotensive population which might not be assessed by AIx.

Performance Analysis of the Clutter Map CFAR Detector with Noncoherent Integration

  • Kim, Chang-Joo;Lee, Hyuck-Jae
    • ETRI Journal
    • /
    • 제15권2호
    • /
    • pp.1-9
    • /
    • 1993
  • Nitzberg has analyzed the detection performance of the clutter map constant false alarm rate (CFAR) detector using single pulse. In this paper, we extend the detection analysis to the clutter map CFAR detector that employs M-pulse noncoherent integration. Detection and false alarm probabilities for Swerling target models are derived. The analytical results show that the larger the number of integrated pulses M, the higher the detection probability. On the other hand, the analytical results for Swerling target models show that the detection performance of the completely decorrelated target signal is better than that of the completely correlated target.

  • PDF

Nonlinear Response of Classical Dynamical Systems to Short Pulses

  • Dellago, Christoph;Mukamel, Shaul
    • Bulletin of the Korean Chemical Society
    • /
    • 제24권8호
    • /
    • pp.1107-1110
    • /
    • 2003
  • Valuable insight into the nonlinear dynamics of a system can be gleaned from its response to a single intense short pulse. We derive expressions for the corresponding nonlinear response functions and show that the fluctuation-dissipation theorem may be extended beyond the linear response limit to an arbitrary pulse intensity. As an illustrative example, we calculate response functions up to 11th order for the regular Lorentz gas in two dimensions.

Shrinkproofing of Wool Fabrics by Pulse Corona Discharge and Enzymes

  • Cho, Sung-Mi;Toru Takagishi;Mitsuru Tahara
    • 한국섬유공학회:학술대회논문집
    • /
    • 한국섬유공학회 2003년도 The Korea-Japan Joint Symposium
    • /
    • pp.96-96
    • /
    • 2003
  • In this article modification of wool fibers and fabrics by pulse corona discharge and enzymes, in particular purified keratinase with a single component has been carried out to improve their surface properties. The shrinkproofing, tensile strength, weight loss, and the primary hand values calculated from the mechanical properties of the dual treated wool fabrics were investigated. In addition, the surface morphology of wool fiber was observed under the dry and wet conditions using an environmental SEM, ESEM.

  • PDF

Application of Tensor Theory to Pulse Sequences

  • 정관진
    • 대한자기공명의과학회:학술대회논문집
    • /
    • 대한자기공명의과학회 2001년도 제6차 학술대회 초록집
    • /
    • pp.57-63
    • /
    • 2001
  • Tensor 하면 최근 3D로 white matter내의 섬유질을 멋있게 그려내는 diffusion tensor를 연상합니다. 하지만 여기서 다룰 tensor는 수학적 연산자(operator)입니다. NMR 혹은 MRI에서 스핀을 vector로 표시하고, 이 vector 스핀이 90도 rf pulse에 의해서 z축에서 x-y Plane으로 rotation되는 것을 vector diagram으로 나타냅니다. 그런데 이 vector notation으로는 스핀에 일어나는 여러 현상들을 수식적으로 모델 하는데 한계가 있습니다. 그래서 도입된 모델이 product operator와 tensor operator입니다 (1, 2, 3). 한 예로 우리가 다루는 proton NMR 신호가 single quantum인데 23Na 등에는 multiple quantum 신호가 생기게 되며 이는 vector로는 나타낼 수가 없으며 tensor로 분석이 가능합니다 (4, 5).

  • PDF

DIGITAL CONTROL OF SINGLE PHASE BUCK-BOOST CONVERTER BY PULSE AREA MODULATION

  • Kim, T.J.;Byun, Y.B.;Joe, K.Y.;Kim, C.U.
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 1998년도 Proceedings ICPE 98 1998 International Conference on Power Electronics
    • /
    • pp.654-657
    • /
    • 1998
  • This paper is described a digital implementation of a pulse area modulation (PAM) method for a unity-power-factor buck-boost converter. A digital controller is designed and implemented by a Digital Signal Processor(DSP) to replace the analog control circuit for PAM. Experimental results are presented and compared with simulations.

  • PDF

PAM방식을 적용한 단상 승강압형 정류기의 디지탈제어 (Digital Control of Single Phase Buck-Boost Converter by Pulse Amplitude Modulation Mehtod)

  • 김태진;변영복;조기연;김철우
    • 전력전자학회:학술대회논문집
    • /
    • 전력전자학회 1998년도 전력전자학술대회 논문집
    • /
    • pp.54-57
    • /
    • 1998
  • This paper describes a digital implementation of a pulse amplitude modulation(PAM) method for a unity-power-factor buck-booster converter. A digital controller is designed and implemented by a Digital Signal Processor(DSP) to replace the analog control circuit for PAM. Experimental results are presented and compared with simulations.

  • PDF

Experimental Waveforms of Single-Pulse Soft-Switching PFC Converter

  • Katsunori Taniguchi;Koh, Kang-Hoon;Lee, Hyun-Woo
    • Journal of Power Electronics
    • /
    • 제4권1호
    • /
    • pp.56-63
    • /
    • 2004
  • A new driving circuit for the SPSS (Single-Pulse Soft-Switching) PFC converter is proposed. The switching device of a SPSS converter switches once in every half cycle of an AC commercial power source. Therefore, it can be solved many problems caused by the high frequency operation. The proposed SPSS converter achieves the soft-switching operation and the EMI noise can be reduced. The resonant capacitor voltage supplies to the resonant inductor even if the input AC voltage is the vicinity of zero cross voltage. Then, the power factor and input current waveform can be improved without delay time. A new driving circuit achieves the operation of SPSS converter by one switching drive circuit. The proposed converter can be satisfied the IEC standard sufficiently

방형파펄즈가열법에 의한 세라믹스의 열물성 측정에 관한 연구 (The measurements of thermophysical properties of ceramics by single rectangular pulse heating method in transient heat source)

  • 차경옥;이경희;임굉
    • 한국결정성장학회지
    • /
    • 제9권6호
    • /
    • pp.612-620
    • /
    • 1999
  • 본 연구에서는 방형파 펄즈 가열법을 이용하여 세라믹 고유전체 열물성치의 측정에 활용하는 것에 대한 가능성을 검토하였다. 여기서 측정의 이론을 설정하고 측정의 자동화를 시도함으로써 매우 짧은 시간내 시료의 열확산계수, 비열 및 열전도율을 얻을 수 있었다. 또한 시료는 실온으로부터 약 1300 K 온도 범위까지 측정하였다.

  • PDF