• 대한수학회보
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• 제42권2호
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• pp.397-404
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• 2005

In this note, we characterize the limiting diffusion of a diploid model by defining the discrete generator for the resealed Markov chain. We conclude that this limiting diffusion model is with uncountable state space and mutation selection and special 'mutation or gene conversion rate'.

• Journal of Microbiology and Biotechnology
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• 제11권4호
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• pp.607-613
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• 2001

The biodegradation rates of diesel oil by a selected diesel-degrading bacterium, Pseudomonas stutzeri strain Y2G1, and microbial consortia composed of combinations of 5 selected diesel-degrading bacterial were determined in liquid and soil systems. The diesel degradation rate by strain Y2G1 linearly increased $(R^2=0.98)$ as the diesel concentration increased up to 12%, and a degradation rate as high as 5.64 g/l/day was obtained. The diesel degradation by strain Y2G1 was significantly affected by several environmental factors, and the optimal conditions for pH, temperature, and moisture content were at pH8, $25^{\circ}C$, and 10%, respectively. In the batch soil microcosm tests, inoculation, especially in the form of a consortium, and the addition of nutrients both significantly enhanced the diesel degradation by a factor of 1.5 and 4, respectively. Aeration of the soil columns effectively accelerated the diesel degradation, and the initial degradation rate was obviously stimulated with the addition of inorganic nutrients. Based on these results, it was concluded that the major rate-limiting factors in the tested diesel-contaminated soil were the presence of inorganic nutrients, oxygen, and diesel-degrading microorganisms. To resolve these limiting parameters, bioremediation strategies were specifically designed for the tested soil, and the successful mitigation of the limiting parameters resulted in an enhancement of the bioremediation efficiency by a factor of 11.

• 정보처리학회논문지C
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• 제12C권5호
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• pp.725-732
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• 2005

본 논문은 기존의 범용 시스템 또는 전용 하드웨어 기반의 네트워크 시스템에서 사용하던 레이트 제한(rate limiting) 기법과 클래스 별 대역폭 관리 기법을 기가 비트 트래픽 처리를 위한 네트워크 프로세서에서 구현하기 위한 방안을 제시하고 이를 구현하여 실험하였다 구현과 실험은 인텔사의 IXP1200 네트워크 프로세서에서 이루어졌으며 그 결과로서 의도한 대역폭으로 제한된 트래픽 레이트의 정확도와 변화하는 입력 레이트에 대한 대역폭 제한 알고리즘의 안정화 시간을 보여 주고 있다. 이를 통하여, 네트워크 프로세서에 적합하도록 구현된 클래스 별 레이트 제한 기능이 일반 시스템에서의 토큰버킷 알고리즘의 오차범위 $10\%$에 근접한 성능으로 잘 동작하는 것을 확인하였다.

• 한국통신학회:학술대회논문집
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• 한국통신학회 1985년도 추계학술발표회논문집
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• pp.21-26
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• 1985

• Journal of the Korean Statistical Society
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• 제28권3호
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• pp.359-370
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• 1999

We considered a change-point hazard rate model generalizing constant hazard rate model. This type of model is very popular in the sense that the Weibull and exponential distributions formulating survival time data are the special cases of it. Maximum likelihood estimation and the asymptotic properties such as the consistency and its limiting distribution of the change-point estimator were discussed. A parametric bootstrap method for finding confidence intervals of the unknown change-point was also suggested and the proposed method is explained through a practical example.

• International Journal of Fluid Machinery and Systems
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• 제4권2호
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• pp.235-242
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• 2011

An application of contra-rotating rotors, in which a rear rotor is in tandem with a front one and these rotors rotate in the opposite direction each other, has been proposed against a demand for developing higher specific speed axial flow pump. One prototype rotors, which we have designed with a conventional method, has given the positive slope of head characteristic curve especially in the rear rotor. It is necessary to understand the internal flow behavior in the rear rotor to establish the design guideline for achieving higher and more reliable performance. In the present study, we carried out the experimental investigations of the internal flow field of the rear rotor, especially at the partial flow rate, by Laser Doppler Velocimetry (LDV) for the main flow and the limiting streamlines observation on rotor surfaces for the boundary layer flows.

• Bulletin of the Korean Chemical Society
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• 제16권3호
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• pp.252-256
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• 1995

Semiempirical MO calculations using the PM3 method are performed on the reactions of acetate esters with substituted phenolate anions. The mechanistic change from rate-limiting formation to breakdown of the anionic intermediate is shown to occur in the gas-phase, especially for meta-nitrophenyl acetate. However the mechanistic change-over takes place at a lower basicity ($pK_0$) of the anion nucleophile than found for the corresponding formate. This lowering of $pK_0$ has been ascribed to the electron donating effect of the methyl group in the acetate. For the reactions involving rate-limiting breakdown of the intermediate, the large Bronsted coefficients, ${\beta}_X({\beta}_{nuc})$, are expected in general, but the magnitude increases to a larger value and the pK0 is lowered accordingly, when an electron-donating nonleaving group, like $CH_3$, is present. This type of nonleaving group effect provides a necessary condition for the carbonyl addition-elimination mechanism with rate-limiting breakdown of the intermediate.

• Applied Biological Chemistry
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• 제19권3호
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• pp.162-171
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• 1976

대사과정(代謝過程)에 있어서 율속단계(律速段階)의 결정은 그 대사(代謝)의 성질을 이해하는 데 대단히 중요한 것이다 저자들은 이것의 결정을 위해서 열역학적(熱力學的) 방법(方法) 대신에 수정된 효소적(酵素的) 방법(方法)을 제시 하였다 이 방법은 단계로 된 대사과정(代謝過程)에서 율속단계(律速段階)에 고유한 효소(酵素)를 가(加)했을 때는 다른 어떤 단계(段階)에 고유한 효소(酵素)를 가(加)했을 때보다도 전체적인 대사(代謝) 반응속도(反應速度)가 가잠 증가한다는 가정(假定)에 기초를 둔 것이다. 본 연구에서는 수정된 효소적(酵素的) 방법(方法)에 의한 반응속도(反應速度) 측정(測定)에 있어서, 이에 영향을 미치는 수종(數種)의 인자(因子)에 대하여 해석(解析)하였으며 주로 동일한 반응속도(反應速度) 형태로 구성된 대사과정(代謝過程)에 대하여 해석(解析)하였다. 이 결과(結果), 본 방법에 의한 율속단계(律速段階)의 결정(決定)은 약간의 제한(制限)이 가(加)해질 경우 임의 형태의 기작(機作)으로 子성된 대사과정(代謝過程)에서도 측정(測定)이 가능하다는 것을 보여 주고 있다.

• 환경위생공학
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• 제16권2호
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• pp.38-46
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• 2001

In this work, the heterogeneous ion exchange membrane was used in a electrodialysis apparatus to treat a Ni planting rinse water because the heterogeneous ion exchange membrane was excellent efficiency as compared with low manufacturing cost, was easy to make, and had a good mechanical properties. For a regeneration of membrane and to obtain the optimal condition for a scale-up of apparatus after treating Ni plating rinse water, we would find about the limiting current density and the concentration polarization. When the Ni plating rinse water 150mg/L was treated with the electrodialysis apparatus using the heterogeneous ion exchange membrane, the limiting current density was about $1.49{\;}mA/\textrm{cm}^2$. And the limiting current density increased with the flow rate and concentration of Ni plating rinse water. We recognized that the used membrane could be reused by periodic backwashing because efficiency was constant when the membrane was backwashed after treating wastewater.

• 산업경영시스템학회지
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• 제2권2호
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• pp.5-10
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• 1979

For investment calculation of capital assets, it is desirable to grasp the limiting factors of its calculation. The limiting factors can be listed as follows; $\circled1$ difficulty in estimating the service life of capital assets. $\circled2$ difficulty in estimating the receipts, and operating and maintenance expenses of the project. $\circled3$ difficulty in determining common Minimum Attractive Rate of Return. $\circled4$ difficulty in estimating the salvage value of the assets. $\circled5$ some limiting factors on present worth calculation of the projects. $\circled6$ Some limiting factors on payout period method of the economic calculation.