• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2002년도 춘계학술대회논문집
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• pp.160-165
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• 2002

The flying height of contact slider is determined by vertical and pitching motions. This paper performed the computer simulation for flying height change of contact slider. It is changed by many parameters, contact stiffness. contact damping, all bearing stiffness ratio and so on. So computer simulation analysis is performed for knowing for what change of these parameters influences in flying height of contact slider. The practical recording zone surface is gotten by using SPM. In recording zone, flying height is simulated for each parameter. the settling time which the flying height of contact slider is lower than 10nm is analyzed over practical disk surface for changing each parameter. Through these results, the contact slider can be analyzed for more accuracy dynamic characteristics.

• Nuclear Engineering and Technology
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• 제30권3호
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• pp.235-244
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• 1998

The parametric model method determines the accident source term which is Presented by a set of source term parameters. In this method, the cumulative distribution of each source term parameter should be derived for its uncertainty analysis. This paper introduces a method of generating the parameters in the form of cumulative distribution using MAAP version 4.0. In MAAP, there are model parameters which could incorporate uncertain physical and/or chemical phenomena. In general, the model parameters do not have a point value but a range. In this paper, considering that, the input values of model parameters influencing each parameter are sampled using LHS. Then, the computation results are shown in cumulative distribution form. For a case study, the CDFs of FCOR and WES of Kori Unit 1 are derived. The target scenarios for the computation are the ones whose initial events are large LOCA, small LOCA and transient, respectively. It is found that the computed CDF's in this study are consistent to those of NUREG-1150 and the use of MAAP is proven to be adequate in assessing the parameters of the severe accident source term.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 하계학술대회 논문집 C
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• pp.1580-1582
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• 1994

In this study, when AC voltage is applied to block type treeing specimen which is fabricated with polyethylene which dielectric characteristics is excellent, from initial tree to final breakdown, Using acoustic emission method. we take statistically on parameter, which is skewness. We experimented on quenching condition and illustrated skewness locus plane so that studied interrelation of life expectation and parameter.

• ETRI Journal
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• 제18권3호
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• pp.161-170
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• 1996

We show that the electrically coupled Hindmarsh-Rose neuronal model exhibits various patterns of phase locking at fixed parameter value. Through the analysis of the effective coupling, the system is shown to be stabilized in one of these patterns according to the initial conditions. This corresponds to the parameter-tuning independent mode-switching mechanism that changes the electrical output of neuronal systems. It is also presented how the stable fixed points of the effective coupling which characterize the phase locking patterns depend on the external current.

• 한국환경과학회지
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• 제12권10호
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• pp.1109-1116
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• 2003

The genetic algorithm is investigated fer parameters estimation of SED (storage - effective drainage) model from the Wi-stream watershed in Nakdong river basin. In the practical application of model, as a number of watershed parameters do not measure directly, it is desirable to make a good estimation from the known rainfall and runoff data. For the estimation of parameters of the SED model using the genetic algorithm, parameters of Green-Ampt equation(SM, K$\_$s/) for the estimation of an effective rainfall and initial storage(y$\_$in/) used in SED model are obtained a regression equation with 5, 10, 20 days antecedent precipitation. And as a consequence of computation, the parameters were obtained to satisfy the proposed objective function. From the comparison of observed and computed hydrographs, it shows a good agreement in the shape and the rising limb, peak, falling limb of hydrograph, so the SED model using the genetic algorithm shows a suitable model for runoff analysis in river basin.

• 한국지능시스템학회논문지
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• 제19권1호
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• pp.102-107
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• 2009

Fuzzy C-Means(FCM)의 단점을 극복하기 위해 제안되었던 PCM은 잡음에는 강하지만 초기 파라미터 값에 민감하고, 상대적으로 가까이에 위치한 prototype들을 형성하는 패턴들의 경우에는 최종 prototype의 위치가 겹치는(동일한) 결과가 나올 수 있다는 단점이 있다. 이러한 PCM의 단점을 극복하기 위해 여러 방법이 제안되었지만, 본 논문에서는 PCM 알고리즘에 Interval Type 2 Fuzzy 접근 방법을 적용하여 PCM 알고리즘의 파라미터에 존재하는 uncertainty를 제어함으로써 성능을 향상시키는 방법을 제안한다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1998년도 제13차 학술회의논문집
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• pp.501-506
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• 1998

A mathematical model is developed to describe the relationship between the manipulated variables (e.g. jacket inlet temperature and feed flow rate) and the important qualities (e.g conversion and weight average molecular weight (Mw)) in a continuous polymerization reactor. The subspace-based identification method for Wiener model is used to retrieve from the discrete sample data the accurate information about both the structure and initial parameter estimates for iterative parameter optimization methods. The comparison of the output of the identified Wiener model with the outputs of a non-linear plant model shows a fairly satisfactory degree of accordance.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1999년도 하계학술대회 논문집 G
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• pp.2929-2931
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• 1999

In this paper, an adaptive fuzzy inference and HCM(Hard C-Means) clustering method are used for on-line fuzzy modeling of nonlinear and complex system. Here HCM clustering method is utilized for determining the initial parameter of membership function of fuzzy premise rules and also avoiding overflow phenomenon during the identification of consequence parameters. To obtain the on-line model structure of fuzzy systems. we use the recursive least square method for the consequent parameter identification. And the proposed on-line identification algorithm is carried out and is evaluated for sewage treatment process system.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2003년도 추계학술대회 논문집 전력기술부문
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• pp.202-204
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• 2003

This paper suggests an optimal parameter setting method by use of parametric protectability index, as the objective function. In this paper, a gradient based optimization method is used under the assumption that the initial values of a parameter is in a convex set including the optimal value, which is verified by a plenty of simulation studies. The proposed method is applied to a sample distribution network to shows its effectiveness.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1994년도 추계학술대회 논문집 학회본부
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• pp.342-344
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• 1994

This paper presents a design technique of SOFLC(Self -Organizing Fuzzy Logic Controller). It is composed of three parts: FLC(Fuzzy Logic Controller) part, RPO (Repeat Parameter Organizing) part, and RTPO (Real Time Parameter Organizing) part. The FLC part is controlled by initial parameters ($a_1$, $a_2$, $a_3$, $b_1$, $b_2$, $b_3$) the RPO part improves parameters by evaluating the performance of control responses controlled by FLC, and the RTPO organizes the parameters for real time in order to have the same value of the control response($y_k$) and the target response($y_k\;^*$).