• Title/Summary/Keyword: uniformly stable

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Stable Isotope Labeled Cytochrome $c_3$ from Desulfovibrio vulgaris on a Defined Medium as Sole Nitrogen Source

  • Kim, Andre;Shim, Yoon-Bo;Kang, Shin-Won;Park, Jang-Su
    • BMB Reports
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    • v.33 no.6
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    • pp.506-509
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    • 2000
  • To obtain Cytochrome $c_3$ labeled with a stable isotope, the conditions of cultivation and the composition of medium for DvMF were examined. The growth of DvMF was steady and reproducible under purging with $N_2$ and under pH control. DvMF was able to go on a defined medium without natural products. The composition of the medium containing a small amount of $NH_4Cl$ as sole nitrogen source was established. Then, uniformly $^{15}N-labeled$ Cytochrome $c_3$ was obtained during the culture of DvMF in a defined medium with $^{15}NH_4Cl$; it was confirmed by $^{1}H-^{15}N$ HMQC.

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STRONG CONVERGENCE AND ALMOST STABILITY OF ISHIKAWA ITERATIVE SCHEMES WITH ERRORS IN BANACH SPACES

  • Zeqing Liu;Kim, Jong-Kyu;Park, Hye-Kyeong
    • Journal of applied mathematics & informatics
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    • v.10 no.1_2
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    • pp.261-275
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    • 2002
  • Let T be a local strongly accretive operator from a real uniformly smooth Banach space X into itself. It is proved that Ishikawa iterative schemes with errors converge strongly to a unique solution of the equations T$\_$x/ = f and x + T$\_$x/ = f, respectively, and are almost T$\_$b/-stable. The related results deal with the strong convergence and almost T$\_$b/-stability of Ishikawa iterative schemes with errors for local strongly pseudocontractive operators.

Improved Attenuation Estimation of Ultrasonic Signals Using Frequency Compounding Method

  • Kim, Hyungsuk;Shim, Jaeyoon;Heo, Seo Weon
    • Journal of Electrical Engineering and Technology
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    • v.13 no.1
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    • pp.430-437
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    • 2018
  • Ultrasonic attenuation is an important parameter in Quantitative Ultrasound and many algorithms have been proposed to improve estimation accuracy and repeatability for multiple independent estimates. In this work, we propose an improved algorithm for estimating ultrasonic attenuation utilizing the optimal frequency compounding technique based on stochastic noise model. We formulate mathematical compounding equations in the AWGN channel model and solve optimization problems to maximize the signal-to-noise ratio for multiple frequency components. Individual estimates are calculated by the reference phantom method which provides very stable results in uniformly attenuating regions. We also propose the guideline to select frequency ranges of reflected RF signals. Simulation results using numerical phantoms show that the proposed optimal frequency compounding method provides improved accuracy while minimizing estimation bias. The estimation variance is reduced by only 16% for the un-compounding case, whereas it is reduced by 68% for the uniformly compounding case. The frequency range corresponding to the half-power for reflected signals also provides robust and efficient estimation performance.

THE STABILITY IN AN INCLINED LAYER OF VISCOELASTIC FLUID FLOW OF HYDROELECTRIC NATURAL CONVECTION

  • El-Bary, A.A.
    • Journal of the Korean Society for Industrial and Applied Mathematics
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    • v.9 no.2
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    • pp.17-27
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    • 2005
  • The problem of the onset stability in an inclined layer of dielectric viscoelastic fluid (Walter's liquid B') is studied. The analysis is made under the simultaneous action of a normal a.c. electric field and the natural convection flow due to uniformly distributed internal heat sources. The power series method used to obtain the eigen value equation which is then solved numerically to obtain the stable and unstable solutions. Numerical results are given and illustrated graphically.

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Error convergence speed of the adaptive algorithm (적응 알고리즘의 오차 수렴속도와 수렴성)

  • 김종수;배준경;박종국
    • 제어로봇시스템학회:학술대회논문집
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    • 1986.10a
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    • pp.83-85
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    • 1986
  • The error differential equations which are derived by using the first error model are uniformly asymptotial stable if the input is bounded and sufficiently rich. In the adaptive control, the speed of convergence of system output or parameter error in such cases is of both practical and theoretical interest. In this paper, the adaptive algorithms(Gradient algorithm, Intergral algorithm) are discussed from the point of view of speed convergence and the modification of adaptive law for prohibition of overadaptation is discussed. The result is compared among this algorithms and the adaptive gain is choosed by this result(the speed of convergence).

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Possibility of Si TFT Technology

  • Noguchi, Takashi
    • 한국정보디스플레이학회:학술대회논문집
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    • 2002.08a
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    • pp.31-33
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    • 2002
  • Si TFTs are applied not only to stacked SRAM but also to FPD. Improvement of device characteristic such as an enhancement of carrier mobility or a reduction of leakage current is studied intensively. The TFT technology is developing based on conventional Si LSI technology. By establishing a stable fabrication process on flexible substrate and high performance characteristic uniformly and reliably, TFT technology has a possibility to develop to SOP or other highly functional applications similar to or beyond the conventional Si LSI in the era of information and telecommunication.

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Nitrogen Isotope Labeled Tetraheme Cytochrome c3 on a Defined Medium

  • Kim, Andre;Park, Jang-Su
    • Bulletin of the Korean Chemical Society
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    • v.26 no.2
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    • pp.278-280
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    • 2005
  • To obtain cytochrome $c_3$ labeled with a stable isotope, the conditions of cultivation and the composition of medium for DvMF were examined. The growth of DvMF was steady and reproducible under purging with $N_2$ and under pH control. DvMF was able to go on a defined medium without natural products. The composition of medium containing a small amount of $NH_4C$l as sole nitrogen source was established. Then, uniformly $^{15}N$labeled cytochrome $c_3$ was obtained during the culture of DvMF in a defined medium with $^{15}NH_4$Cl; it was confirmed by $^1H-^{15}N$ HMQC.

Fabrication of 3-dimensional Sn-C Composites Using Microsphere (미소구체를 이용한 3차원 Sn-C 복합체 제조)

  • Park, Bo-Gun;Kim, Seuk-Buom;Park, Yong-Joon
    • Journal of the Korean Institute of Electrical and Electronic Material Engineers
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    • v.23 no.9
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    • pp.741-746
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    • 2010
  • Three-dimensionally ordered macro-porous Sn-C composites were prepared by using polystyrene microsphere as a template. The Sn-C composites were composed of well-interconnected pore with circular shape and wall structure with wall thickness of a few tens of nano-meters. This porous three-dimensional structure is readily and uniformly accessible to the electrolyte, which facilitates lithium ion diffusion during charge-discharge reactions. The wall thickness of the composites was increased as the increase of Sn content of the composite. From EDS analysis, it is confirmed that the Sn was dispersed uniformly in Sn-C composites. The capacity was increased as the Sn content increased, which is due to Sn anode with high capacity. The Sn-C composites with high Sn content showed superior cyclic performances. Such enhancement is ascribed to the thick wall thickness and small pore size of the sample with high Sn content. The Sn-C composite with Sn 30 wt% showed relatively high capacity and stable cycle life, however, the stability of the 3-dimensional structure should be enhanced by further work.

MRI-Guided Gadolinium Neutron Capture Therapy

  • Ji-Ae Park;Jung Young Kim;Hee-Kyung Kim
    • Journal of Radiopharmaceuticals and Molecular Probes
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    • v.8 no.2
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    • pp.113-118
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    • 2022
  • Gadolinium neutron capture therapy (Gd-NCT) is a precision radiation therapy that kills cancer cells using the neutron capture reaction that occurs when 157Gd hits thermal neutrons. 157Gd has the highest thermal neutron capture cross section of 254,000 barns among stable isotopes in the periodic table. Another stable isotope, 155Gd, also has a high thermal neutron trapping area (~ 60,700 barns), so gadolinium that exists in nature can be used as a Gd-NCT drug. Gd-NCT is a mixed kinetic energy of low-energy and high-energy ionizing particles, which can be uniformly distributed throughout the tumor tissue, thereby solving the disadvantage of heterogeneous dose distribution in tumor tissue. The Gd complexes of small-sized molecule are widely used as contrast agents for magnetic resonance imaging (MRI) in clinical practice. Therefore, these compounds can be used not only for diagnosis but also therapy when considering the concept of Gd-NCT. This multifunctional trial can look forward to new medical advance into NCT clinical practices. In this review, we introduce gadolinium compounds suitable for Gd-NCT and describe the necessity of image guided Gd-NCT.

Combustion Characteristics in a Heat-recirculating Microemitter for a Micro Thermophotovoltaic System (초소형 열광전변환 장치용 열재순환 초소형 이미터 내 연소특성에 관한 연구)

  • Lee, Kyoung-Ho;Kwon, Oh-Chae
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.2360-2365
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    • 2007
  • A new microemitter (microcombustor) configuration for a micro thermophotovoltaic system in which thermal energy is directly converted into electrical energy through thermal radiation was investigated experimentally and computationally. The microemitter as a thermal heat source was designed for a few watt power-generating micro thermophotovoltaic system. In order to satisfy the primary requirements for designing the microemitter, i.e., stable burning in the small confinement and maximum heat transfer through the emitting walls but uniform distribution of temperature along the walls, the present microemitter is cylindrical with an annular-type shield for heat recirculation to apply for the excessive enthalpy concept. Results show that the heat recirculation substantially improves the performance of the microemitter: the observed and predicted thermal radiation from the microemitter walls indicated that heat generated in the microemitter is uniformly emitted.

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