• 한국음향학회지
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• 제26권6호
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• pp.276-285
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• 2007

본 논문에서는 현재까지 주파수 영역에서 개발된 4종류의 라우드스피커 TS 매개변수 규명법들에 대하여 비교 검토하였다. 보이스 코일 인덕터에 대한 상세한 모델링을 위해 주파수 종속 모델링 기법을 소개하였고 관련된 매개변수들을 유도하였다. 라우드스피커의 동적 질량을 알고 있을 때에 TS 매개변수를 규명하는 방법을 소개하고 이를 실제 라우드스피커에 적용할 때에 고려할 사항들도 기술하였다. 1채널 장비로 전기 임피던스를 측정할 때에는 크기만을 측정하게 되므로 위상값 추정을 위해 최소 위상 변환법을 사용하는 방법도 기술하였다.

• 한국농공학회지
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• 제28권2호
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• pp.42-52
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• 1986

This study involves the estimation of optimal ranges of parameters for a linear watershed model. A well-known TANK model was chosen and a linear combination of four tanks assumed. The model was used to simulate daily streamflow for six watersheds of different sizes and by a trial-and-error approach a set of optimal parameters defined. The parameters were related to watershed sizes and land use conditions. Optimal parameters for ungaged conditions were defined from the relationships; daily streamflow simulated and compared to the observed date. The simulated results were in a general agreement with the data.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1986년도 한국자동제어학술회의논문집; 한국과학기술대학, 충남; 17-18 Oct. 1986
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• pp.456-458
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• 1986

A method for on-line tuning of the PID-controller parameters for a discrete-time multivariable process system is presented. And it is based on a step change in the controller set point. The system is presumed to be a linear, open loop stable and known one. The controller parameters are determined by the performance criterion and Fletcher-Powell methods.

• Communications for Statistical Applications and Methods
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• 제7권1호
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• pp.199-210
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• 2000

We shall propose several estimators for the shape and scale parameters I the Weibull distribution based upon the complete or truncated samples when both parameters are functions of a known exposure level and study properties for proposed several estimators

• 한국정보디스플레이학회:학술대회논문집
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• 한국정보디스플레이학회 2005년도 International Meeting on Information Displayvol.I
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• pp.195-198
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• 2005

Using theoretical analysis based on Landau theory, it is shown that only five phenomenological parameters are necessary to describe the twelve bulk elastic constants of a biaxial nematic phase. Further, a simple method for determining the values of these five parameters experimentally is given. Comparison with the values of the well-known splay, twist, and bend elastic constants of the uniaial nematic is made.

• 제어로봇시스템학회논문지
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• 제3권6호
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• pp.555-562
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• 1997

With only the classical PID controller applied to control of a DC motor, good (target) performance characteristic of the controller can be obtained if all the model parameters of DC motor and operating conditions such as external load torque, disturbance, etc. are known exactly. However, in case when some of system parameters or operating conditions are uncertain or unknown, the fixed PID controller does not guarantee good performance, which is assumed with precisely known system parameters and operating conditions. In view of this and the robustness enhancement of DC motor control system, we propose a PID learning controller which consists of a set of learning rules for PID gain tuning and learning of an auxiliary input. The proposed PID learning controller is shown to drive the state of uncertain DC motor system with unknown system parameters and external load torque to the desired one world wide asymptotically. Computer simulation and experimental results are given to demonstrate the effectiveness of the proposed PID learning controller, thereby showing its superiority to the conventional fixed PID controller.

• 대한음성학회:학술대회논문집
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• 대한음성학회 2002년도 11월 학술대회지
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• pp.115-118
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• 2002

Neural networks have been known to have great discriminative power in pattern classification problems. In this paper, the multilayer perceptron neural networks are employed to automatically detect laryngeal pathology in speech. Also new feature parameters are introduced which can reflect the periodicity of speech and its perturbation. These parameters and cepstral coefficients are used as input of the multilayer perceptron neural networks. According to the experiment using Korean disordered speech database, incorporation of new parameters with cepstral coefficients outperforms the case with only cepstral coefficients.

• Journal of the Korean Data and Information Science Society
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• 제13권2호
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• pp.295-305
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• 2002

We shall propose several estimators for the shape and scale parameters in a generalized uniform distribution when both parameters are polynomial of a known exposure level, and obtain expectations and variances for their proposed estimators. And we shall compare numerically efficiencies for the several proposed estimators for the shape and scale parameters in a generalized uniform distribution in the small sample sizes.

• 전기의세계
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• 제31권2호
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• pp.126-131
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• 1982

Induction motors are known to cause voltage dip, oscillating torque and inrush current on the dynamic period. To compensate for these undesirable effects, the prediction of dynamic performances is required. The dynamic performances are determinated by circuit time constants. From this point of view, in this paper, the dynamic equivalent circuit included only three time-constant parameters are presented. To predict more simply dynamic performances, the new characteristics time constant parameters are analyzed, and now these parameters are described as the function of circuit time constants. This paper reviews and analyzes the use of series capacitance compensations, and the use of this analysis can make simply a prediction about oscillating conditions.

• 한국생산제조학회지
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• 제9권5호
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• pp.58-64
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• 2000

This paper proposes a method for determining optimal EDM parameters based on discharge area from the physical model of a tool electrode. Main parameters, which affect the EDM performance, are peak value of currents, pulse-on time, and pulse-off time. Such parameters are closely dependent on the discharge area in EDM process. In this paper the discharge area is estimated from the CMM scanning data to the tool electrode. The method is very useful when any geometric information to the tool electrode is not provided from tool modeler or producer. The method consists of following four steps. First a triangulation mesh is constructed from the CMM data. Secondly, the z-map is modeled from the triangulated mesh. Thirdly, the discharge area is estimated from intersection between the z-map model and a z-height plane. Finally, the machining parameters are easily calculated by some known EDM equations to the discharge area. An example is introduced to show that the machining parameters are calculated from the CMM data to a tool electrode.