• Title/Summary/Keyword: rate dependent

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Preservation of Marine Heterotrophic Bacteria by Using a Deep-freezing Method

  • Park, Shin-Hye;Lee, Hyun-Sang;Lee, Hong-Kum
    • Journal of Microbiology
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    • v.39 no.3
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    • pp.240-243
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    • 2001
  • The effect of cryoprotectants and suspending solutions on the preservation of marine heterotophic bacteria was investigated. Six halotolerant and four halophilic bacterial isolates suspended in either distilled water or artificial seawater were preserved in glycerol and dimethylsulfoxide at -70$\^{C}$, respectively. After one year of preservation, the recovery rates on the appropriate agar plates were estimated. The survival rate was found to be dependent on the strain tested, regardless of the preservation conditions tested.

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Numerical Analysis Methods for Heat Flow in Fire Compartment (화재실의 열유동 해석을 위한 수치 해석 방법)

  • Kim, Gwang-Seon;Son, Bong-Se
    • Fire Protection Technology
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    • s.16
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    • pp.20-23
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    • 1994
  • This article investigates the different numerical methods, which are widely used for purpose of simulating a fire compartment the particular numerical methods such as finite difference, finite element, control Volume, and finite analysis are discribed in order to understand basic concepts and their applications. The fire simulations using fferent methods for the different physical geometrics have been reported in many recent literatures The convergence rate, the accuracy, and the stability are no simply dependent upon the specific method, The study of popular nu-merical methods by being compared among those is therefore significant to understand the nu-merical simulation of fire compartment.

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Theoreitica1 analysis of plasma processes in discharge excited KrF laser (방전어기 KrF 레이저의 프라즈마 프로세서 해석)

  • Choi, Boo-Yeon;Lee, Choo-His
    • Proceedings of the KIEE Conference
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    • 1989.11a
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    • pp.505-508
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    • 1989
  • A computer simulation code of UV preionized discharge KrF laser is developed, including time dependent circuit equations, boltzmann equations, and plasma kinetic equations for various atomic and molecular species. Rate constants for electron collision processes are calculated with a boltzmann equations as a function of E/N. In this study, we studied mainly the $KrF^*$ formation process, relaxation process, and the 248nm absorption process as a function of charging voltage.

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Magnetic attitude control of a satellite (지자기를 이용한 위성체의 자세제어)

  • 엄광섭;박동조
    • 제어로봇시스템학회:학술대회논문집
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    • 1992.10a
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    • pp.159-164
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    • 1992
  • In this paper, the complex nonlinear dynamics of a satellite is obtained. And it is shown that several limitations exist when the magnetorquer is used as an active actuator to attitude control. Such limitations cause a delayed convergence of pitch and roll angle. The simulation results insure that the roll angle bias is dependent on the z axis spin rate. And a heuristic algorithm is applied to control the attitude libration through the computer simulations.

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The Effect of Partial Response Signaling Pulses under Wireless Communication Environments

  • Park, Won-Ho;Kong, Hyung-Yun
    • Proceedings of the IEEK Conference
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    • 1999.06a
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    • pp.57-60
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    • 1999
  • In many radio communication environments, there is a special component, called inter-symbol interference (ISI), mused by multipath time delay of signal and ISI components impose limitation of the data transmission rate. In this paper, we consider signaling pulse shapes, called partial response signaling (PRS), for minimizing the effect of ISI and show the improvement of performance by applying one of the partial-response signaling (PRS) pulses to two types of receiver system under dependent noise environments through the Monte-Carlo computer simulations.

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종속 고장을 가지는 원형 Consecutive-k-out-of-n:F 시스템의 경제적 설계

  • 윤원영;김귀래;고용석;류기열
    • Proceedings of the Korean Reliability Society Conference
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    • 2000.11a
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    • pp.387-395
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    • 2000
  • Circular consecutive-k-out-of-n:F system when the failure of component is dependent is studied. We assume that the failure of a component in the system increase the failure rate of the survivor which is working just before the failed component. In this case, a mean time to failure (MTTF), a average failure number of the system, and the expected cost per unit time are obtained. Then the minimum number of consecutive failed components to cause system failure to minimize the expected cost per unit time is determined as searching paths to system failure. And various numerical examples are studied.

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A Study on the Pladstic Instable Flow in Free Forging (자유 단조의 소성불안정 유동에 관한 연구)

  • 이용성
    • Proceedings of the Korean Society for Technology of Plasticity Conference
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    • 2000.04a
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    • pp.96-100
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    • 2000
  • It is difficult to predict material behavior of forming process because the plastic instable flow phenomenon happens in practical forming process I. e. upsetting backward extrusion piercing indentation. In view of the direct relationship between instable material flow and quality defects of the products we should find out their phenomena, In this study we introduced the plastic spin and the kinematic hardening considering the kinematic hardening constitutive equation for rate-dependent material. Also analysis of upset forging is carried out using the rigid plastic FEM with Al7075

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ESTIMATING THE SIMULTANEOUS CONFIDENCE LEVELS FOR THE DIFFERENCE OF PROPORTIONS FROM MULTIVARIATE BINOMIAL DISTRIBUTIONS

  • Jeong, Hyeong-Chul;Jhun, Myoung-Shic;Lee, Jae-Won
    • Journal of the Korean Statistical Society
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    • v.36 no.3
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    • pp.397-410
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    • 2007
  • For the two groups data from multivariate binomial distribution, we consider a bootstrap approach to inferring the simultaneous confidence level and its standard error of a collection of the dependent confidence intervals for the difference of proportions with an experimentwise error rate at the a level are presented. The bootstrap method is used to estimate the simultaneous confidence probability for the difference of proportions.

Performance of W-CDMA System for Wideband Multipath Channel Environments (광대역 다중경로 채널특성에 따른 W-CDMA 시스템의 성능분석)

  • 오동진;나인학;김철성
    • Proceedings of the IEEK Conference
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    • 2001.06a
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    • pp.97-100
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    • 2001
  • The performance of mobile radio communication system is dependent on various factors such as channel environment. Especially, the number of multipath components of mobile radio channel and multipath delay property in CDMA system for different bandwidths are changed. Therefore, using multipath components, Rake receiver provides improvement of performance of W-CDMA system is evaluated by computer simulation over the types of ITU-R wideband channel model and spreading rate. The result shows that the performance of CDMA adapting RAKE receiver is Improved by the increase of multipath components in equal level of the received power.

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