• Title/Summary/Keyword: binary signal

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Research of an image retrival method using binary subimage (이진 부분영상을 이용한 영상 검색 기법에 관한 연구)

  • 정순영;최민규;남재열
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2000.08a
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    • pp.329-332
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    • 2000
  • 영상 검색 기법 중 기존의 색상 정보만을 이용한 기법에는 많은 한계가 존재하기 때문에 현재의 검색 기법 혹은 상용 검색 프로그램들은 두가지 이상의 검색 기법을 동시에 이용한다. 본 논문에서는 이진 영상을 이용하여 형태 정보를 추출하고 색상 정보와의 결합을 이용한 검색 기법을 제안한다. 이진화된 영상만으로도 상당수의 형태 정보를 포함하고 있기 때문에 최소한의 계산을 이용하여 영상의 개략적인 형태를 파악할 수 있는 방법을 제안한다. 아울러, 이진화된 형태 정보로 자칫 놓칠 수 있는 형태 정보를 보완하기 위하여 영상 내의 객체의 위치 정보를 이용하기 위해 부분영상으로 영상을 분할하여 좀 더 효율적인 검색을 가능하게 하는 기법을 제안한다.

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Characteristics of holographic storage of random-phase-modulation-added binary amplitude data (랜덤 위상변조가 가미된 이진 진폭 데이터 영상의 홀로그래픽 저장 특성)

  • 오용석;신동학;장주석
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.5 no.2
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    • pp.289-296
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    • 2001
  • We propose a method to add phase-modulation to binary amplitude data pages using a twisted-nematic liquid crystal display as a dynamic phase mask. For this, the phase modulation characteristics of the display were examined both theoretically and experimentally, and an unexpected abnormal phenomenon was found experimentally in which the modulation property changed as the incident beam intensity increased. To investigate the characteristics of holographically storing the binary data images, eight pages of holograms were stored at one spot of in un-thick Dupont's photopolymer with angle multiplexing. When phase-modulation-added pages were stored at the Fourier plane, the uniformity of the signal beam at the plane was improved, and thus more holograms can be recorded with our method, compared with the conventional case of using only binary amplitude modulation under the same condition.

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Moving object segmentation using Markov Random Field (마코프 랜덤 필드를 이용한 움직이는 객체의 분할에 관한 연구)

  • 정철곤;김중규
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.27 no.3A
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    • pp.221-230
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    • 2002
  • This paper presents a new moving object segmentation algorithm using markov random field. The algorithm is based on signal detection theory. That is to say, motion of moving object is decided by binary decision rule, and false decision is corrected by markov random field model. The procedure toward complete segmentation consists of two steps: motion detection and object segmentation. First, motion detection decides the presence of motion on velocity vector by binary decision rule. And velocity vector is generated by optical flow. Second, object segmentation cancels noise by Bayes rule. Experimental results demonstrate the efficiency of the presented method.

Binary Mask Estimation using Training-based SNR Estimation for Improving Speech Intelligibility (음성 명료도 향상을 위한 학습 기반의 신호 대 잡음 비 추정을 이용한 이산 마스크 추정 방법)

  • Kim, Gibak
    • Journal of Broadcast Engineering
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    • v.17 no.6
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    • pp.1061-1068
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    • 2012
  • This paper deals with a noise reduction algorithm which uses the binary masking approach in the time-frequency domain to improve speech intelligibility. In the binary masking approach, the noise-corrupted speech is decomposed into time-frequency units. Noise-dominant time-frequency units are removed by setting the corresponding binary masks as "0"s and target-dominant units are retained untouched by assigning mask "1"s. We propose a binary mask estimation by comparing the local signal-to-noise ratio (SNR) to a threshold. The local SNR is estimated by a training-based approach. An optimal threshold is proposed, which is obtained from observing the distribution of the training database. The proposed method is evaluated by normal-hearing subjects and the intelligibility scores are computed by counting the number of words correctly recognized.

A Study on Frequency Hopping Signal Detection Using a Polyphase DFT Filterbank (다상 DFT 필터뱅크를 이용한 도약신호 검출에 관한 연구)

  • Kwon, Jeong-A;Lee, Cho-Ho;Jeong, Eui-Rim
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.17 no.4
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    • pp.789-796
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    • 2013
  • It is known that the detection of hopping signals without any information about hopping duration and hopping frequency is rather difficult. This paper considers the blind detection of hopping signal's information such as hopping duration and hopping frequency from the sampled wideband signals. In order to find hopping information from the wideband signals, multiple narrow-band filters are required in general, which leads to huge implementation complexity. Instead, this paper employs the polyphase DFT(discrete Fourier transform) filterbank to reduce the implementation complexity. This paper propose hopping signal detection algorithm from the polyphase DFT filterbank output. Specifically, based on the binary image processing, the proposed algorithm is developed to decrease the memory size and H/W complexity. The performance of the proposed algorithm is evaluated through the computer simulation and FPGA (field programmable gate array) implementation.

Analysis of underwater acoustic communication channel environment in Kyungcheon Lake (경천호에서의 수중 음향 통신 채널 환경 분석)

  • Kim, Yong-Cheol;An, Jong-Min;Lee, Ho-Jun;Lee, Sang-Kug;Chun, JaeHak
    • The Journal of the Acoustical Society of Korea
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    • v.38 no.1
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    • pp.1-8
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    • 2019
  • This paper estimated communication parameters according to underwater channel environment of lake for underwater acoustic communication. This paper calculated coherence time and coherence bandwidth through two experiments in actual lake environments. In both experiments, the chirp signal for channel estimation and the BPSK (Binary Phase Shift Keying) signal for calculating the bit error rate were transmitted. In each experiment, the distance between transmitter and receiver was 300 m to 400 m, and 500 m to 600 m. The coherence times calculated in experiment 1 and experiment 2 are 175 msec and 340 msec, and the coherence bandwidths are 10 Hz and 5.71 Hz, respectively. It is confirmed that the experimental results are more appropriate because the synchronization and the bit error rate performance are better only when the length of the synchronization signal and the interval of the pilot signal in the frame are shorter than the coherence time.

System Identification of a Diesel Engine -Throttle-Smoke Response- (디젤 기관(機關)의 계통식별(系統識別) -연료주입율(燃料注入率) 대(對) 매연반응(煤煙反應)-)

  • Cho, H.K.
    • Journal of Biosystems Engineering
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    • v.16 no.2
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    • pp.111-117
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    • 1991
  • An empirical model for diesel engine control was obtained using a system identification method. A pseudo-random binary sequence was used as an input signal. Spectral anaylsis was used to find the frequency response of system. Model parameters of transfer functions were obtained using nonlinear regression.

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PSK Error Performance with Impulsive Noise and Cochannel Interference (임펄스 잡음 및 동일 채널 간섭하의 PSK신호의 오율 특성)

  • 강병옥;조성준
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.20 no.1
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    • pp.55-62
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    • 1983
  • The error rate performance of phase shift Keyed(PSK) signal has been evaluated in terms of carrier-to-noise ratio(CNR), carrier-to-interferer ratio(CIR), impulsive index, and the phase difference between signal and interferer in the environment of cochannel PSK inter-ference and impulsive noise. We hays derived a general equation of the probability density function (p.d.f.) of output of coherent phase detector. And the error rate of the received binary PSK(BPSK) signal has been numerically evaluated. The graphic results show us that the best case is the situation of the signal and the inter- ferer meet with orthogonal phase.

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