• 대한전자공학회논문지
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• 제19권1호
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• pp.29-34
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• 1982

U형 수준선의 특성임피던스는 유한차분법에 의해서도 계산될 수 있으나 이 연구에서는 모먼트법에 의하여 그의 특성 임피던스를 계산한다. 유한차분법에 의한 계산결과와 모먼트법에 의한 결과에는 10%정도의 차가 좌우한다. 그러나 내부도체가 외부도체의 중앙에 있을 때 모먼트법에 의한 결과는 선석적인 방법에 의한 결과와 거의 일치된다.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2004년도 춘계종합학술대회
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• pp.434-438
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• 2004

This paper has proposed presumable method of ergonomics estimate index from evoked potential of visual stimulation for establishment a fixed ergonomics estimate index. The proposed method presumes continuance time and amplitude of ergonomics using prony method. Band characteristic of alpha and beta band, and that of background and evoked potential was analyzed using FFT method. And, that were presumed continuance time and amplitude of ergonomics using porny method. As a result of that proposed method presumed band characteristic, continuance time and amplitude of ergonomics, classification of ergonomics of impatient, rage and fear were practicable.

• 한국전자파학회논문지
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• 제16권11호
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• pp.1099-1105
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• 2005

TRL 오차 수정 방법은 PCB 위에 제작된 고주파 소자를 측정할 때 많이 사용되는 방법이지만 오차 수정을 위해 제작된 표준 전송선 패턴의 특성 임피던스를 알아야만 보다 정확하게 측정 오차를 수정할 수 있다. 기존의 방법에서는 저항을 종단 처리한 표준 패턴을 추가로 이용하여 전송선의 단위 길이당 커패시턴스를 계산하고 주파수에 대해 fitting하는 방법으로 표준 전송선의 특성 임피던스를 계산하고 있으나 제작상의 부정확성에 의해 추출된 특성 임피던스가 영향을 받고 있음을 확인하였다. 본 논문에서는 측정된 S-parameter를 이용하여 제작상의 부정확성을 줄일 수 있고 기존 방법보다 정확한 특성 임피던스를 추출할 수 있다.

• 전기학회논문지P
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• 제57권3호
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• pp.236-243
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• 2008

This paper analyses magnetic flux saturation of matching transformer considering characteristic of dynamic voltage restorer(DVR) system to solve voltage sags which are considered the dominant disturbances affecting power quality. This DVR consist of PWM inverter to inject arbitrary voltage, LC low pass filter and matching transformer for isolation and grid connection. However, the matching transformer has an excess of inrush current by magnetic flux saturation in the core of transformer. Due to this inrush current, the rating of matching transformers is double for needed nominal rating for protection of DVR. Therefore, in this paper, an advanced modeling method of magnetic flux saturation is used to analyze a magnitude and characteristic of magnetizing current. Simulation and experimental results considering characteristic of DVR system are provided to demonstrate the validity of the proposed analysis method.

• 한국통신학회논문지
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• 제22권11호
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• pp.2531-2542
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• 1997

This paper describes a method for region segmentation and string extractionin documents which are mixed with text, graphic and picture images by the use of the structural characteristic of connceted components. In segmentation of non-text regionas, with connection-characteristic functions which are made by structural characteristic of connected components, segmentation process is progressed. In the string extraction, first we organize basic-unit-region of which vertical and horizontal length are 1/4 of average length of connection components. Second, by merging the basic-unit-regions one other that have smaller values than a given connection intensity threshold. Third, by linking the word blocks with similar block anagles, initial strings are cresed. Finally the whold strings are generated by merging remaining word blocks whose angles are not decided, if their height and prosition are similar to the initial strings. This method can extract strings that are neither horizontal nor of various character sizes. Through computer exteriments with different style documents, we have shown that the feasibility of our method successes.

• 한국멀티미디어학회논문지
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• 제17권10호
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• pp.1171-1181
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• 2014

In this paper, we propose improved methods which are image conversion and extraction method of watershed seed using morphological characteristic of teeth on complement image. Conventional tooth segmentation methods are occurred low detection ratio at molar region and over, overlap segmentation owing to specular reflection and morphological feature of molars. Therefore, in order to solve the problems of the conventional methods, we propose the image conversion method and improved extraction method of watershed seed. First, the image conversion method is performed using RGB, HSI space of tooth image for to extract boundary and seed of watershed efficiently. Second, watershed seed is reconstructed using morphological characteristic of teeth. Last, individual tooth segmentation is performed using proposed seed of watershed by watershed algorithm. Therefore, as a result of comparison with marker controlled watershed algorithm and the proposed method, we confirmed higher detection ratio and accuracy than marker controlled watershed algorithm.

• 한국감성과학회:학술대회논문집
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• 한국감성과학회 2000년도 춘계 학술대회 및 국제 감성공학 심포지움 논문집 Proceeding of the 2000 Spring Conference of KOSES and International Sensibility Ergonomics Symposium
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• pp.157-162
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• 2000

Discriminant analysis is a method to relate whether the objects have a specific characteristic or not with their 'continuous' attribute values and, for given objects, to estimate whether they have a specific characteristic or not by their values of discriminant scores gotten from their attribute values. The author developed the new 'computational' method of discriminant analysis without specific hypotheses or assumptions and, by this new method, we can find 'feasible' solutions under the conditions required by our actual problems. In this paper, the author tried to apply this new method to the discrimination of logical relations. If this trial could be a success, we can apply this new method of discriminant analysis to the problems about relating the specific characteristic of the objects with their 'discrete' attribute values. The result was successful and the applicability of discriminant analysis could be expanded as a method for constructing the models for "estimating impressions".

• 한국산학기술학회논문지
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• 제11권7호
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• pp.2541-2548
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• 2010

본 논문에서는 결함접지구조와 포토닉 밴드갭과 같은 주기구조가 삽입된 전송선로의 특성 임피던스 계산에 대하여 기술한다. ${\lambda}$/4 전송선로 이론을 이용한 계산하는 종래 방법을 고찰하고, 이 방법에 의한 계산 결과가 주파수 의존성이 커서 신뢰도가 낮다는 문제점을 제시한다. 균일한 유전체 기판에 구현된 전송선로의 특성 임피던스 계산에 적용되는 해석적인 방법을 주기구조가 결합된 전송선로에서도 적용될 수 있음을 보인다. ${\lambda}$/4 전송선로 방법과 대신 해석적 방법으로 특성 임피던스를 구하고, 후자의 결과가 주파수에 관계없이 비교적 고정된 값을 가짐을 제시한다. 또한 종래에 특성 임피던스 계산 사례가 없었던 PBG 구조를 지닌 전송선로에 대해서도 특성 임피던스를 계산한다. 시뮬레이션뿐만 아니라 직접 제작하여 측정한 S-파라미터로부터 각각 특성 임피던스를 계산하고 서로 비교하여 상당히 유사함을 보인다. 그리고 이를 통하여 해석적 방법에 의한 특성 임피던스의 결정 방법이 DGS와 PBG와 같은 주기구조가 결합된 전송선로의 특성 임피던스 계산에 잘 적용될 수 있음을 보인다.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2007년도 춘계학술대회논문집
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• pp.109-114
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• 2007

Analytical method to analyze the effect of tolerance on the modal characteristic of multi-body systems in dynamic equilibrium position is suggested in this paper. Monte-Carlo Method is conventionally employed to perform the tolerance analysis. However, Monte-Carlo Method spends too much time for analysis and has a greater or less accuracy depending on sample condition. To resolve these problems, an analytical method is suggested in this paper. By employing the sensitivity information of mass, damping and stiffness matrices, the sensitivities of damped natural frequencies and the transfer function can be calculated at the dynamic equilibrium position. The effect of tolerance on the modal characteristic can be analyzed from tolerance analysis method.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 2005년도 ICCAS
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• pp.11-15
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• 2005

This paper presents a method to determine the characteristic polynomial of a closed loop all-pole system in order to obtain desired transient response in terms of the overshoot and speed (rising/settling time). The method adjusts the overshoot by doing some changes in the characteristic ratios of the Bessel-Thompson filter. The closed loop speediness is then tuned by suitable choice of the generalized time constant. Simulation results are presented to evaluate the achievements and make comparison with those of a similar method.