• 제목/요약/키워드: The Masking Method

검색결과 334건 처리시간 0.025초

로렌츠 시스템에 바탕을 둔 혼돈신호 덧씌우기 (Chaotic Signal Masking Based on Lorens System)

  • 장태주;송익호;배진수;김홍길
    • 방송공학회논문지
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    • 제1권1호
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    • pp.62-66
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    • 1996
  • 이 논문에서는 로렌츠시스템에 바탕을 둔 신호 덧씌우기 방법의 한 구조를 생각하였는데, 이는 정보신호를 송신시스템 안으로 귀환시키는 구조이다. 이 방법은 수신쪽에서 정보신호를 정확히 복원하며 정보신호의 크기를 크게 할 수 있다. 모의실험을 통하여 정보신호의 복원과 암호화 특성을 살펴보았다. 그리하여 다른 방식보다 성능이 뛰어남을 알 수 있었다.

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Identifying Multiple Leverage Points ad Outliers in Multivariate Linear Models

  • Yoo, Jong-Young
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.667-676
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    • 2000
  • This paper focuses on the problem of detecting multiple leverage points and outliers in multivariate linear models. It is well known that he identification of these points is affected by masking and swamping effects. To identify them, Rousseeuw(1985) used robust estimators of MVE(Minimum Volume Ellipsoids), which have the breakdown point of 50% approximately. And Rousseeuw and van Zomeren(1990) suggested the robust distance based on MVE, however, of which the computation is extremely difficult when the number of observations n is large. In this study, e propose a new algorithm to reduce the computational difficulty of MVE. The proposed method is powerful in identifying multiple leverage points and outlies and also effective in reducing the computational difficulty of MVE.

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DESIGN OF DESIRABLE LOUDNESS RATINGS FOR ISDN TELEPHONE

  • Hong, Jin-Woo;Kang, Kyeong-Ok;Kang, Seong-Hoon
    • 한국음향학회:학술대회논문집
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    • 한국음향학회 1994년도 FIFTH WESTERN PACIFIC REGIONAL ACOUSTICS CONFERENCE SEOUL KOREA
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    • pp.1070-1075
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    • 1994
  • This paper describes the method for designing loudness ratings as transmission quality for ISDN telephone connected to fully digital network. To design the desirable loudness ratings for ISDN telephone, the model system of digital speech communication for subjective test is developed and opinion tests for establishing the optimal CODEC input level, the range of overall loudness rating, and sidetone masking rating are performed. As the results, the desirable ranges of loudness ratings are proposed as 6 to 8dB for sending, 0 to 2dB for receiving, and 10 to 14dB for sidetone masking rating.

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Identification of Multiple Outlying Cells in Multi-way Tables

  • Lee, Jong Cheol;Hong, Chong Sun
    • Communications for Statistical Applications and Methods
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    • 제7권3호
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    • pp.687-698
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    • 2000
  • An identification method is proposed in order to detect more than one outlying cells in multi-way contingency tables. The iterative proportional fitting method is applied to get expected values of several suspected outlying cells. Since the proposed method uses minimal sufficient statistics under quasi log-linear models, expected counts of outlying cells could be estimated under any hierarchical log-linear models. This method is an extension of the backwards-stepping method of Simonoff(1988) and requires les iteration to identify outlying cells.

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Recognition of the Passport by Using Fuzzy Binarization and Enhanced Fuzzy Neural Networks

  • Kim, Kwang-Baek
    • 한국지능시스템학회:학술대회논문집
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    • 한국퍼지및지능시스템학회 2003년도 ISIS 2003
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    • pp.603-607
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    • 2003
  • The judgment of forged passports plays an important role in the immigration control system, for which the automatic and accurate processing is required because of the rapid increase of travelers. So, as the preprocessing phase for the judgment of forged passports, this paper proposed the novel method for the recognition of passport based on the fuzzy binarization and the fuzzy RBF neural network newly proposed. first, for the extraction of individual codes being recognized, the paper extracts code sequence blocks including individual codes by applying the Sobel masking, the horizontal smearing and the contour tracking algorithm in turn to the passport image, binarizes the extracted blocks by using the fuzzy binarization based on the membership function of trapezoid type, and, as the last step, recovers and extracts individual codes from the binarized areas by applying the CDM masking and the vertical smearing. Next, the paper proposed the enhanced fuzzy RBF neural network that adapts the enhanced fuzzy ART network to the middle layer and applied to the recognition of individual codes. The results of the experiment for performance evaluation on the real passport images showed that the proposed method in the paper has the improved performance in the recognition of passport.

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정현파 모델을 이용한 오디오 신호의 심리음향적 분석 및 합성 (Analysis and Synthesis of Audio Signals using a Sinusoidal Model with Psychoacoustic Criteria)

  • 남승현;강경옥;홍진우
    • 한국음향학회지
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    • 제18권2호
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    • pp.77-82
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    • 1999
  • 정현파 모델은 음성과 오디오 신호의 분석과 합성에 많이 활용되어 왔으며 최근 고음질 저비트율 오디오 부호화에 효율적인 방법의 하나로 대두되고 있다. 정현파 모델을 이용한 오디오 신호의 분석과 합성에서 중요한 단계 중의 하나는 순음의 검출이다. 본 논문은 정현파를 이용한 오디오 신호의 분석과 합성에 매스킹 효과와 매스킹 인덱스 그리고 JNDf(Just Noticeable Difference in Frequency) 등의 심리음향적 기준들을 활용하는 효율적인 방안을 제안하였다. 모의실험 결과, 심리음향적 기준을 사용하면 합성된 음질에 거의 영향을 주지 않으면서 합성에 사용되는 정현파의 개수를 현저하게 줄일 수 있었음을 알 수 있었다.

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스마트폰에서 이미지 필터링 효과의 직관적 조정을 위한 내장센서의 적용 기법 (A Technique of Applying Embedded Sensors to Intuitive Adjustment of Image Filtering Effect in Smart Phone)

  • 김지연;권석민;정종진
    • 한국멀티미디어학회논문지
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    • 제18권8호
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    • pp.960-967
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    • 2015
  • In this paper, we propose a user interface technique based on embedded sensors applying to apps in smart phone. Especially, we implement avata generation application using image filtering technique for photo image in smart phone. In the application, The embedded sensors are used as intuitive user interface to adjust the image filtering effect for making user satisfied effect in real time after the system produced the image filtering effect for avatar. This technique provides not a simple typed method of parameter values adjustment but a new intuitively emotional adjustment method in image filtering applications. The proposed technique can use sound values from embedded mike sensor for adjusting key values of sketch filter effect if the smart phone user produces sound. Similiarly the proposed technique can use coordinate values from embedded acceleration sensor for adjusting masking values of oil painting filter effect and use brightness values from embedded light sensor for adjusting masking values of sharp filter effect. Finally, we implement image filtering application and evaluate efficiency and effectiveness for the proposed technique.

Forest Fire Damage Assessment Using UAV Images: A Case Study on Goseong-Sokcho Forest Fire in 2019

  • Yeom, Junho;Han, Youkyung;Kim, Taeheon;Kim, Yongmin
    • 한국측량학회지
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    • 제37권5호
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    • pp.351-357
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    • 2019
  • UAV (Unmanned Aerial Vehicle) images can be exploited for rapid forest fire damage assessment by virtue of UAV systems' advantages. In 2019, catastrophic forest fire occurred in Goseong and Sokcho, Korea and burned 1,757 hectares of forests. We visited the town in Goseong where suffered the most severe damage and conducted UAV flights for forest fire damage assessment. In this study, economic and rapid damage assessment method for forest fire has been proposed using UAV systems equipped with only a RGB sensor. First, forest masking was performed using automatic elevation thresholding to extract forest area. Then ExG (Excess Green) vegetation index which can be calculated without near-infrared band was adopted to extract damaged forests. In addition, entropy filtering was applied to ExG for better differentiation between damaged and non-damaged forest. We could confirm that the proposed forest masking can screen out non-forest land covers such as bare soil, agriculture lands, and artificial objects. In addition, entropy filtering enhanced the ExG homogeneity difference between damaged and non-damaged forests. The automatically detected damaged forests of the proposed method showed high accuracy of 87%.

상황인식 이동성 예측 모델에서의 효율적인 포워딩 경로 산출 기법 (Efficient Forwarding Path Computing Method for Context-Awareness Mobility Prediction Model)

  • 정래진;오영준;이강환
    • 한국정보통신학회:학술대회논문집
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    • 한국정보통신학회 2014년도 추계학술대회
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    • pp.93-95
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    • 2014
  • 본 논문은 계층적 클러스터 구조에서, 상황인식 이동성 예측모델을 통해 예측된 이동성으로 효율적인 포워딩 경로를 산출하는 기법을 제안한다. 이동성으로 인하여 노드 간 연결이 쉽게 변화하는 환경에서 통신의 불안정성을 극복하기 위해, 제안하는 알고리즘은 상황인식 이동성 예측모델을 통해 얻은 클러스터의 예측된 속성정보를 활용한다. 예측정보를 통해 클러스터간의 연결성을 매트릭스의 형태로 정리하며, 마스킹 기법을 응용한 포워딩 경로 산출 기법을 통해 효율적인 경로를 도출한다. 모의실험 결과, 제안하는 알고리즘으로 클러스터의 이동성을 고려하여 노드 간의 연결이 오래 지속될 수 있는 포워딩 경로를 선택 후에 전송함으로써 지연시간이 줄어드는 결과가 기대된다.

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