• Biotechnology and Bioprocess Engineering:BBE
• /
• 제11권1호
• /
• pp.61-66
• /
• 2006

The simple Langmuir isotherm is frequently employed to describe the equilibrium behavior of protein adsorption on a wide variety of adsorbents. The two adjustable parameters of the Langmuir isotherm - the saturation capacity, or $q_m$, and the dissociation constant, $K_d$ - are usually estimated by fitting the isotherm equation to the equilibrium data acquired from batch equilibration experiments. In this study, we have evaluated the possibility of estimating $q_m$ and $K_d$ for the adsorption of bovine serum albumin to a cation exchanger using batch kinetic data. A rate model predicated on the kinetic form of the Langmuir isotherm, with three adjustable parameters ($q_m,\;K_d$, and a rate constant), was fitted to a single kinetic profile. The value of $q_m$ determined as the result of this approach was quantitatively consistent with the $q_m$ value derived from the traditional batch equilibrium data. However, the $K_d$ value could not be retrieved from the kinetic profile, as the model fit proved insensitive to this parameter. Sensitivity analysis provided significant insight into the identifiability of the three model parameters.

• Journal of applied mathematics & informatics
• /
• 제26권3_4호
• /
• pp.519-530
• /
• 2008

This paper studies the multi-domain coupled system of one dimensional Arctic temperature field and establishes identification model about the thermodynamic parameters of sea ice (heat storage capacity, density and conductivity) by the so-called output least-square estimate according to the temperature data acquired by a monitor buoy installed in the Arctic ocean. By the optimal control theory, the existence and dependability of weak solution and the identifiability of identification model have been given. Moreover, necessary optimality condition is proposed. Furthermore, the optimal algorithm for the identification model is constructed. By using the optimal thermodynamic parameters of Arctic sea ice, the numerical simulation is implemented, and the numerical results of temperature distribution of Arctic sea ice are demonstrated.

• 한국경영과학회지
• /
• 제22권4호
• /
• pp.151-165
• /
• 1997

We propose a method for estimating the probability of perfect PM from successive failure times of a repairable system. The system under study is maintained preventively at periodic times, and it undergoes minimal repair at failure. We consider Brown-Proschan imperfect PM model in which the system is restored to a condition as good as new with probability P and is otherwise restored to its condition just prior to failure. We discuss the identifiability problem when the PM modes are not recorded. The expectation-maximization principle is employed to handle the incomplete data problem. We assume that the lifetime distribution belongs to a parametric family with increasing failure rate. For the two parameter Weibull lifetime distribution, we propose a specific algorithm for finding the maximum lifelihood estimates of the reliability parameters : the probability of perfect PM (P), as well as the distribution parameters. The estimation method will provide useful results for maintaining real systems.

• 한국구조물진단유지관리공학회 논문집
• /
• 제9권2호
• /
• pp.217-224
• /
• 2005

모드자료를 이용한 SI기법을 효과적으로 적용하기 위하여 최적 모델을 선택하는 방법을 제안하였다. 축소된 유한요소 모델 대신 가능한 상세한 유한요소 모델을 정하고 SI기법으로 식별하였다. 다만 미지변수의 수를 조절하기 위하여 부재그룹 개념을 도입하였다. 최적 모델은 시도된 부재그룹 경우 중에서 최소의 통계적 오차를 갖는 것으로 선택하였다. 본 논문에서는 단경간 box-girder교에 대한 예제 수행을 통하여 제안된 방법을 검토하였다.