• 한국컴퓨터정보학회논문지
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• 제12권5호
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• pp.163-170
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• 2007

본 논문에서는 압축된 비디오 신호의 움직임 벡터 및 DCT 계수로부터 움직임 객체를 추출하는 새로운 기법을 제시한다. 움직임 객체 추출에 관한 기술은 내용 기반 검색, 타겟트래킹 등 다양한 분야에서 필요로 한다. 움직임 객체 블록의 추출을 위해서 움직임 벡터와 DCT계수 가 선택적으로 이용되는 2-모드 방식의 기법이 제시된다. 또한, 제시된 기법은 DCT 변환 영역상의 계수들만을 이용하기 때문에 완전히 복호화된 정보를 필요로 하지 않는 장점을 갖는다. 제시된 기법을 바탕으로 몇 가지 테스터 영상에 대해 모의 실험을 실시한 결과 양호한 결과를 얻을 수 있었다.

• 한국산학기술학회:학술대회논문집
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• 한국산학기술학회 2004년도 춘계학술대회
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• pp.285-287
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• 2004

$100\%$천연향을 이용하여 제작, 개발된 해충기피제의 기피력을 테스트하였다. 해충기피제를 착용한 그룹과 착용하지 않은 그룹으로 구분하여 실험실에서 사육한 모기와 서해안에 위치한 몽산포 해수욕장, 동해안에 위치한 낙산 및 선악 해수욕장과 천안에 있는 태조산에서 해충에 대한 기피력을 측정하였으며, 각 그룹별로 5명씩 5회에 걸쳐 각 회당 1시간동안에 흡혈개체로부터 물린 갯수를 확인하여 이들의 평균값을 계산하였다. 그 결과, 실험실에서는 $91\%$, 몽산포 해수욕장에서는 $78\%$, 낙산 및 설악 해수욕장에서는 $93\%$, 태조산에서는 $90\%$의 기피력을 보여주었으며, 이는 상당히 탁월한 기피 효과를 나타내었다.

• 전기학회논문지
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• 제61권1호
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• pp.148-154
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• 2012

For a successful checkpointing strategy, we should place checkpoints so as to optimize fault-tolerance capability of real-time systems. This paper presents a novel scheme of checkpoint placement for real-time systems with periodic multi-tasks. Under the influence of transient faults, multi-tasks are scheduled by the Rate Monotonic (RM) algorithm. The optimal checkpoint intervals are derived to maximize the probability of task completion. In particular, this paper is concerned about the general case that the deadline of a task is longer than the period. Compared with the special condition that the deadline is equal to or less than the period, this general case causes a more complicate test procedure for schedulability of the RM algorithm with respect to a given set of checkpoint re-execution vectors. The probability of task completion is also derived in a more complex form. A case study is given to show the applicability of the proposed scheme.

• Bulletin of the Korean Chemical Society
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• 제15권1호
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• pp.74-77
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• 1994

Rare earth elements (REE) were individual separated by applying the gradient elution via HPLC using ${\alpha}-hydroxyisobutyric$ acid (HIBA) as an eluent. However, the overlap of Y and Dy peaks was too severe to obtain the resolution of these two peaks. The target transformation factor analysis (TTFA) was applied to resolve the elution peaks of Y and Dy. [A]$_{raw}$ formed from the absorbances of mixed solution was factor analyzed. The abstract factor analysis(AFA) was used to determine the number of components that contributed to the poorly resolved peaks. The error theory in the AFA showed that the number of components was 2. The test vectors which correspond to pure component were selected from the standard solutions of Y and Dy. TTFA was accomplished by target testing. The results showed that the resolution of two peaks as well as the determination of Y and Dy were possible by the factor analysis.

• Journal of Power Electronics
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• 제19권5호
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• pp.1153-1161
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• 2019

A current sharing controller is proposed in this paper for parallel-connected converters. The proposed controller is based on the calculation of the magnitudes of system current space vectors. Good current distribution between parallel converters is achieved with only one Proportional-Integral (PI) compensator. The proposed controller is analyzed and the circulating current impedance is derived for paralleled systems. The performance of the new control strategy is experimentally verified using two parallel connected converters employing Space Vector Pulse Width Modulation (SVPWM) feeding a passive RL load and a 2.2 kW three-phase induction motor load. The obtained test results show a reduction in the current imbalance ratio between the converters in the experimental setup from 53.9% to only 0.2% with the induction motor load.

• Communications for Statistical Applications and Methods
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• 제29권6호
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• pp.655-664
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• 2022

On the motivation by an integrative study of multi-omics data, we are interested in estimating the structure of the sparse cross correlation matrix of two high-dimensional random vectors. We rewrite the problem as a multiple testing problem and propose a new method to estimate the sparse structure of the cross correlation matrix. To do so, we test the correlation coefficients simultaneously and threshold the correlation coefficients by controlling FRD at a predetermined level α. Further, we apply the proposed method and an alternative adaptive thresholding procedure by Cai and Liu (2016) to the integrative analysis of the protein expression data (X) and the mRNA expression data (Y) in TCGA breast cancer cohort. By varying the FDR level α, we show that the new procedure is consistently more efficient in estimating the sparse structure of cross correlation matrix than the alternative one.

• 센서학회지
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• 제33권3호
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• pp.119-124
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• 2024

Effective fire sensing is important to protect lives and property from the disaster. In this paper, we present an intelligent visual sensing method for detecting fires based on machine learning techniques. The proposed method involves a two-step process. In the first step, fire and non-fire images are used to train a convolutional neural network (CNN), and in the next step, feature vectors consisting of 256 values obtained from the CNN are used for the learning of a support vector machine (SVM). Linear and nonlinear SVMs with different parameters are intensively tested. We found that the proposed hybrid method using an SVM with a linear kernel effectively increased the recall rate of fire image detection without compromising detection accuracy when an imbalanced dataset was used for learning. This is a major contribution of this study because recall is important, particularly in the sensing of disaster situations such as fires. In our experiments, the proposed system exhibited an accuracy of 96.9% and a recall rate of 92.9% for test image data.

• 한국펄프종이공학회:학술대회논문집
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• 한국펄프종이공학회 2006년도 PAN PACIFIC CONFERENCE vol.2
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• pp.227-230
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• 2006

The $St{\ddot{o}}ckigt$ sizing test of the most-commonly used sizing tests is easily influenced by the individual testers' bias in recognizing red coloration. Therefore the test had to be modified to improve its reliability and reproducibility by automated recognition of a coloration procedure during testing. In order to achieve this, all measured variables occurring during the $St{\ddot{o}}ckigt$ test was first be analyzed and then reflected in the new automatic system. Secondly, the most important principle applied was to transform the RGB values of the droplet image to hue (H), saturation (S) and value (V) respectively. This is because RGB cannot be used as a color standard, owing to RGB's peculiarity of being seriously affected by the observer's point of view. Therefore, the droplet color had to be separated into three distinct factors, namely the HSV values, in order to allow linear analysis of the droplet color. When the average values of the vectors calculated during color variation from yellow to brown were plotted against time, it was possible to determine the vector value of hue, the most sensitive factor among HSV, at the specific time by differentiation of a function when it exceeds the critical point. Then, the specific time consumed up to the critical point was regarded as the $St{\ddot{o}}ckigt$ sizing degree. The conventional method took more time to recognize an ending point of coloration than the automatic method, and in addition the error ranges of the conventional sizing degrees on the specific addition points of AKD were wider than those of the automatic method.

• 국제지역연구
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• 제15권1호
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• pp.219-240
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• 2011

본 연구는 주가 및 부동산가격 변화에 의한 화폐수요함수의 자산효과를 분석하였다. 부동산가격 자료의 획득이 가능한 10개국, 25개 통화단위를 대상으로 분석하였으며, Johansen 공적분 검정에 추가하여 Pesaran, Shin and Smith의 한계검정을 적용하였다. 또한, 효율적인 공적분벡터의 추정을 위하여 Stock and Watson의 DOLS를 적용하였다. 분석결과, 화폐수요함수에 주가와 부동산가격을 포함시킬 경우 장기균형관계의 성립 가능성이 월등히 증가하였다. 특히 ARDL-한계검정에 의하면 12개 통화단위는 자산 가격을 포함하는 경우에만 공적분관계가 존재하는 것으로 나타났다. 이러한 결과들은 자산가격의 변화가 장기화폐수요에 매우 유의한 영향을 준다는 의미이다. DOLS에 의한 공적분 벡터의 추정결과에서도 주가와 부동산가격이 매우 유의한 영향을 주는 것으로 나타났다. 주가는 12개 통화단위에서 통계적으로 유의한 영향을 미치는 반면 부동산가격은 19개 통화단위에서 통계적으로 유의하였다. 특히 부동산가격은 싱가포르 M1을 제외하고 나머지 모든 국가의 통화단위에서 통계적으로 유의하게 나타나 장기 화폐수요함수 추정에서 부동산시장의 중요성이 부각된다. 한편 주가와 부동산가격의 계수부호나 크기는 국가별로, 통화단위별로 상이하게 나타났다.

• 한국통신학회논문지
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• 제33권8C호
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• pp.575-582
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• 2008

본 논문에서는 ITU-T의 SG15에서 채택된 G.729.1 광대역 음성 코덱을 ARM926EJ-S(R) 프로세서 코어에 적용하기 위해 기본연산자 및 산술기능 함수를 포함한 G.729.1 코덱 프로그램 일부를 어셈블리어로 변환하여 실시간으로 동작하도록 구현한 절차 및 결과를 기술하였다. G.729.1은 $8{\sim}32kbps$의 가변 전송률을 갖는 ITU-T 표준 광대역 음성 코덱이며, 입력신호는 8kHz 또는 16 kHz로 샘플링 되어 샘플 당 16 비트로 양자화된 PCM 신호를 입력받는다. 이 코덱은 앞서 표준화된 G.729 및 0.729A와 상호 호환이 가능하며 음질 향상을 위해 기존의 협대역($300{\sim}3,400Hz$)에 비해 대역폭을 광대역($50{\sim}7,000Hz$)으로 확장한 버전이다. 실시간으로 구현된 G.729.1 광대역 음성 코덱은 32kbps에서 인코더와 디코더 부분이 각각 약 31.2 MCPS 및 22.8 MCPS의 복잡도를 가지며, 실제 임베디드 시스템에서의 실행 시간은 인코더와 디코더 평균 6.75ms와 4.76ms로 총 11.5ms가 걸렸다. 또한 이 코덱은 ITU-T에서 제공하는 모든 테스트 벡터에 대해 비트 단위로 정확하게 시험하여 통과하였으며, 실제 인터넷 전화기에 적용한 실시간 음성통화에서 정상적으로 동작하였다.