• Proceedings of the IEEK Conference
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• 2000.09a
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• pp.453-456
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• 2000

본 논문에서는 색상정보를 이용한 얼굴 검출 알고리즘에 대해 소개하고자 한다. 여러 개의 얼굴 검출에 적용되는 이 알고리즘은 피부색의 학습 과정과 입력영상에 대한 얼굴 검출 과정으로 크게 두 가지로 나눌 수 있다. 특히 본 연구에서는 피부색이 본 논문에서 제안한 새로운 RGB 영역에서 직선을 이루는 특징을 이용하여 학습 data를 구성한다. 이렇게 구성된 data를 입력영상에 적용함으로써 1차 얼굴 후보영역을 결정한다. 그런 후 1차 후보영역을 세로방향과 가로방향으로 투영시킴으로써 최종 얼굴 영역을 찾아낸다. 실험을 통해 이 알고리즘은 기존의 색상정보를 이용한 얼굴검출 방법에 비해 얼굴 개수에 상관없이 높은 검출 성공률을 보여주었다.

• Proceedings of the Acoustical Society of Korea Conference
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• 1998.06c
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• pp.167-170
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• 1998

음성신호의 특징적인 성분인 피치를 검출하는 알고리즘 중 실시산 구현이 손쉬운 3단계를 클리핑 알고리즘을 PC상에서의 처리를 위하여 구현하였다. 이 알고리즘을 통하여 검출되는 피치의 안정성 및 정확성을 높이기 위해서 적용된 창함수, LPF, 클리핑 자기상관값계산, 비선형 감쇄, 등의 전처리 필터링과, 배수피치 검출 및 정정, 메디언 필터링을 사용하여 피치를 검출하였다. 또한 이 알고리즘을 이용하여 DSP의 도움을 얻지 않고 PC상에서 음성을 분석하여 스펙트로그램, 파형, 에너지, 피치 등을 출력하는 프로그램인 Visual Analysis Tool for sounds(VAT)의 출력화면을 통하여 피치검출을 나타내었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.12B
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• pp.2401-2406
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• 1999

Various techniques extracting feature vectors have been studied for the cut detection in compressed video data. In case of using the histogram of occurrence of pixel's values as a feature vector, the precise detection of cuts would not be expected because of not considering the spatial correlation of pixels. And more sophisticated algorithms such as CCV(Color Coherent Vector) and Correlrogram tend to be used. Though these methods can be able to detect cuts rather precisely, they require much more processing time because of a enormous amount of computations. In this paper we propose a method of the cut detection using spatial correlation of DC values of luminance components in MPEG video sequence. This requires less processing time and also It can increase the rates of detecting the correct cuts by using advanced comparative method.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.8C
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• pp.1025-1033
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• 2004

This paper covers the detection of covert direct sequence spread spectrum signal without the PN(Pseudo Noise) code information. Due to its low probability of interception, the difficulty of spectrum surveillance increases. Detection parameters are the signal existence of given bandwidth, the length of spreading sequence used by transmitter, and the identification of spreading code for detected chip length. The triple correlation function(TCF) value which is one of the higher order statistical signal processing techniques can be used to detect spread spectrum signal without a prior knowledge, but, it has weakness that TCF results depend on the spread data sequence in actual application. This paper proposes the new scheme that not only overcomes the weakness but also presents better performance than the traditional TCF scheme. The performance comparison of conventional TCF with proposed technique shows that the triple correlation estimator(TCE) has better detection capability.

• The Journal of the Korea Contents Association
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• v.13 no.10
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• pp.54-61
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• 2013

This paper presents a simplified hardware based edge detection circuit which is based on an analog correlator combining with the neighbor pixels in CMOS image sensor. A pixel element of the edge detector consists of an active pixel sensor and an analog correlator circuit which connects two neighbor pixels. The edge detector shares a comparator on each column that the comparator decides an edge of the target pixel with an adjustable reference voltage. The circuit detects image edge from CIS directly that reduces area and power consumption 4 times and 20%, respectively, compared with the previous works. And also it has advantage to regulate sensitivity of the edge detection because the threshold value is able to control externally. The fabricated chip has 34% of fill factor and 0.9 ${\mu}W$ of power per a pixel under 0.18 ${\mu}m$ CMOS technology.

• Journal of Broadcast Engineering
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• v.25 no.6
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• pp.870-881
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• 2020

This paper presents cell ID (cell identity) detection schemes using PSS/SSS (primary synchronization signal/secondary synchronization signal) for 5G NR (new radio) system and evaluates the detection performance. In this paper, we consider two cell ID detection schemes, i.e. two-stage detection and joint detection schemes. The two-stage detection scheme consists of two stages which estimate a channel gain between a transmitter and receiver and detect the PSS and SSS sequences. The joint detection scheme jointly detects the PSS and SSS sequences. In addition, this paper presents coherent and non-coherent combining schemes. The coherent scheme calculates the correlation value for the total length of the given PSS and SSS sequences, and the non-coherent combining scheme calculates the correlation within each group by dividing the total length of the sequence into several groups and then combines them non-coherently. For the detection schemes considered in this paper, the detection error rates of PSS, SSS and overall cell ID are evaluated and compared through computer simulations. The simulation results show that the joint detection scheme outperforms the two-stage detection scheme for both coherent and non-coherent combining schemes, but the two-stage detection scheme can greatly reduce the computational complexity compared to the joint detection scheme. In addition, the non-coherent combining detection scheme shows better performance under the additive white Gaussian noise (AWGN), fixed, and mobile environments.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.10 no.6
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• pp.107-111
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• 2010

The damage of tire by damage material classification method is researched as used ultrasonic wave signal to occur at a tire during vehicle driving. Auto-correlation function after having passed through an envelope detecting preprocess is used for detecting periodicity because of occurring periodic ultrasonic waves signal with tire revolution. One revolution cycle time of a damaged tire and period that calculated auto-correlation function appeared equally in experiment. The result that can classification whether or not there was a tire damage is established.

• Proceedings of the KIEE Conference
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• 2008.10b
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• pp.482-483
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• 2008

본 연구는 수면 중 무구속적 방식으로 에어 베개에 부착한 PPG 센서에서 호흡 및 심박을 검출하는 방법을 제안하였다. 본 연구에서 사용된 반사형 PPG 센서는 광원이 피부로 투과되어 혈관의 이완 및 수축 정도를 측정할 수 있다. 반사형 PPG 센서로부터 하드웨어 모듈을 통과한 생체 신호는 AD 변환되어 PC로 전송된다 PPG에서 검출된 분당 심박 수는 전송된 신호의 밸리점간의 시간 간격을 이용하여 추출하며 호흡 신호는 밸리점의 크기를 연결하여 추출하였다. 검출된 호흡 신호와 기준 호흡 신호간의 상관성을 확인하기 위해 기준신호로 호흡과 심박을 동시에 측정하여 그 결과를 분석하였다. PPG 센서로부터 획득한 심박 및 호흡 신호는 기준신호들과 높은 상관성을 가지며 호흡시 발생하는 움직임과 호흡 속도에 영향을 받는다는 것을 알 수 있었다.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.24 no.8A
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• pp.1099-1106
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• 1999

In this paper, the bit error ratio(BER) performance of multi-carrier CDMA system in multi-user/multi-path environment is analytically derived, and effect of interferences due to multi-user, multi-carrier, multi-path is analyzed. A multi-carrier/multi-user/multi-path joint detection scheme incorporating a decorrelating detector is proposed, and its performance as well as the enhancement of noise due to decorrelating process are analyzed. BER of the proposed joint detection scheme is only slightly degraded compared to the ideal case of single user environment.

• Journal of Korean Society of Environmental Engineers
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• v.28 no.8
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• pp.843-851
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• 2006

Although the detected amounts of those disease-causing(oo)cysts were high at each point in 2001, the detected amounts of Cryptosporidium and Giardia had decreased at low levels below 10(oo)cysts until 2004. Considered the detection results of each season, the most highly detected amounts of(oo)cysts were mostly recorded in summer and late summer(from June to September), while the site which the biggest amount was detected, was the point at Goryeung. The relation of Cryptosporidium with the water quality items was low, but the relations of Cryptosporidium and Giardia with turbidity were high($R^2$=0.4914, $R^2$=0.6176 respectively). And the detected amounts of Cryptosporidium and Giardia were relatively high, 20(oo)cysts/20L when the turbidity was more than 20 NTU. It was also found that the relation between the distribution of Cryptosporidium and Giardia was high, $R^2$=0.8432 and the density of Giardia was generally higher than that of Cryptosporidium. And Cryptosporidium and Giardia were simultaneously detected at each point. The primary sources that affected the density of those(oo)cysts were the livestock waste water and sewage.