• Title/Summary/Keyword: detector combination

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A Novel Multi-view Face Detection Method Based on Improved Real Adaboost Algorithm

  • Xu, Wenkai;Lee, Eung-Joo
    • KSII Transactions on Internet and Information Systems (TIIS)
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    • v.7 no.11
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    • pp.2720-2736
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    • 2013
  • Multi-view face detection has become an active area for research in the last few years. In this paper, a novel multi-view human face detection algorithm based on improved real Adaboost is presented. Real Adaboost algorithm is improved by weighted combination of weak classifiers and the approximately best combination coefficients are obtained. After that, we proved that the function of sample weight adjusting method and weak classifier training method is to guarantee the independence of weak classifiers. A coarse-to-fine hierarchical face detector combining the high efficiency of Haar feature with pose estimation phase based on our real Adaboost algorithm is proposed. This algorithm reduces training time cost greatly compared with classical real Adaboost algorithm. In addition, it speeds up strong classifier converging and reduces the number of weak classifiers. For frontal face detection, the experiments on MIT+CMU frontal face test set result a 96.4% correct rate with 528 false alarms; for multi-view face in real time test set result a 94.7 % correct rate. The experimental results verified the effectiveness of the proposed approach.

A Simple Speech/Non-speech Classifier Using Adaptive Boosting

  • Kwon, Oh-Wook;Lee, Te-Won
    • The Journal of the Acoustical Society of Korea
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    • v.22 no.3E
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    • pp.124-132
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    • 2003
  • We propose a new method for speech/non-speech classifiers based on concepts of the adaptive boosting (AdaBoost) algorithm in order to detect speech for robust speech recognition. The method uses a combination of simple base classifiers through the AdaBoost algorithm and a set of optimized speech features combined with spectral subtraction. The key benefits of this method are the simple implementation, low computational complexity and the avoidance of the over-fitting problem. We checked the validity of the method by comparing its performance with the speech/non-speech classifier used in a standard voice activity detector. For speech recognition purpose, additional performance improvements were achieved by the adoption of new features including speech band energies and MFCC-based spectral distortion. For the same false alarm rate, the method reduced 20-50% of miss errors.

Development of a portable near infrared device for skin moisture by using a microspectrometer

  • Woo, Young-Ah;Suh, Eun-jung;Ahn, Jhii-Weon;Kim, Hyo-Jin
    • Proceedings of the SCSK Conference
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    • 2003.09a
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    • pp.203-224
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    • 2003
  • In recent years, a miniature spectrometer has been extensively developed due to the combination of fiber optics and semiconductor detector arrays. This type of miniature spectrometer has advantages of low price and robustness because of the capability of mass production and no moving parts are required such as lenses, mirrors and scanning monochromator. In this study, for skin diagnostics, a portable near infrared (NIR) system has been developed using a LlGA microspectrometer, which is photo-diode arrays-type.(omitted)

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Compositional Sugar Analysis of Antitumor Polysaccharidees by High Performance Liquid Chromatography and Gas Chromatography

  • Kim, Yeong-Shik;Park, Kyung-Shin;Park, Ho-Koon;Kim, Sung-Whan
    • Archives of Pharmacal Research
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    • v.17 no.5
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    • pp.337-342
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    • 1994
  • Carbohydrate analysis is important in studying structure and activity of complex polysaccharides. New analytical method was applied to get an information on the composition of polysaccharides showing antitumor activity. Monosaccharides were labeled with 7-amino-1, 3-naph-thalenedisulfonic acid (7-AGA) by reductive amination and separated by HPLC. Five kinds of polysaccharides from Basidiomycetes were hydrolyzed and analyzed in combination with electrophresis and HPLC. At the same time, alditol acetate derivatives were prepared and analyzed by gas chromatography. Two different techniques using different derivatization methods showed very similar results. The monosaccharides from Coriolus versicolor and Cordyceps militaris were glucose and galactose. Phellinus linteus composed of glucose, glactose, mannose, arabinose and fucose. The HPLC method with fluorescence detector was very sensitive compared to other methods.

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Illumination Insensitive Corner Detector Based on Color NTGST (조명 변화에 둔감한 컬러 NTGST기반 코너 검출자)

  • 박기현;서경석;최흥문
    • Proceedings of the IEEK Conference
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    • 2003.07e
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    • pp.1775-1778
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    • 2003
  • 본 논문에서는 컬러 NTGST (noise-tolerant generalized symmetry transform)를 기초로 하여 부분적인 조명 변화뿐 아니라 그림자 및 잡음이 있는 환경에서도 효과적으로 코너만을 검출할 수 있는 코너 검출자를 제안하였다. 제안한 코너 검출자는 잡음에 둔감한 NTGST를 기초로 하여 코너에 가까울수록, 두 직선 에지가 이루는 각이 작을수록 큰 값이 코너에 누적되도록 하여 코너의 정확한 위치를 검출할 수 있도록 하였다 특히 조명 변화에 둔감한 HSI 색 공간에서 색상 (hue) 성분을 강조하고 채도 (saturation) 및 휘도 (intensity) 성분을 보조적인 정보로 활용함으로써 부분적인 조명 및 그림자의 영향을 줄일 수 있도록 가중조합 벡터 미분 연산자 (weighted combination of vector gradient vector operator)를 제안 적용하여 그림자로 인한 거짓 경계선 및 거짓 코너를 제거할 수 있도록 하였다. 실험을 통하여 제안한 코너 검출 방법이 잡음 및 조명 변화에 둔감하게 효과적으로 코너를 검출함을 확인하였다.

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Accuracy Improvement of Lattice Parameters Measured from Electron Diffraction Data (전자회절을 이용한 격자상수의 측정 정확도 향상)

  • Lee, Sang-Gil;Song, Kyung;Kim, Jin-Gyu
    • Applied Microscopy
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    • v.41 no.1
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    • pp.75-79
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    • 2011
  • For quantitative analysis of nano-crystal structure, we reported the accuracy improvement method of lattice parameters measured from electron diffraction. For calculation of Au lattice parameters used as a standard crystal structure, it was considered two different acquisition methods (detector and enegy-filter) and three different calculation methods (conventional, least-square and regression fit). As a result, the measurement reliability could be enhanced by using CCD camera which gives higher performance, while energy-filtering did not affect the improvement the camera constant accuracy. Also, the accuracy of lattice parameters could be improved up to $10^{-4}$ order by regression fitting with correction formula. Finally, it is expected that the combination of regression fitting and intensity extraction from energy-filtered precession electron diffraction gives a solution of quantitative structure analysis for unknown nano-crystals.

Optimization of Headspace Analysis of Volatile Compounds from Oxidized Fish Oil

  • Shin, Eui-Cheol;Jang, Hae-Jin;Lee, Hyung-Il;An, Hae-Jung;Lee, Yang-Bong
    • Preventive Nutrition and Food Science
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    • v.8 no.4
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    • pp.315-320
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    • 2003
  • Headspace volatile compounds of oxidized fish oil were analyzed by the combination of hexane solvent or solid phase microextraction, gas chromatography and mass selective detector. The optimum condition of headspace analysis by hexane trapping was 23 min absorption time, 96$^{\circ}C$ sample temperature and 20 mL/min air flow rate. The numbers of volatile compounds identified by solvent trapping and SPME were 35 and 14, respectively. Groups having the largest amount and many kinds were hydrocarbons and aldehydes, respectively. The numbers of aldehydes were 15 and 6 for solvent trap and SPME, respectively. These basic data could be used as indicators for the quality changes of fish oil.

Determination of L-asparagine Using a Garlic Tissue Electrode (마늘의 조직 센서를 이용한 L-asparagine의 정량)

  • 김성진;김기묘;배유진;이은엽;허문회;안문규
    • YAKHAK HOEJI
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    • v.39 no.2
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    • pp.113-117
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    • 1995
  • Garlic tissue cells are employed for the conversion of L-asparagine into ammonia. An ammonia gas electrode is used as a detector. The effect of pH, buffer solution, temperature and life time of electrode to have used were investigated in order to optimize the electrode response. The combination of L-asparaginase in garlic tissue cells and the gas electrode response linearly to Lasparagine over the concentration range 1.0$\times$10$^{-4}$~1.0$\times$10$^{-1}$ M with a slope of 72.0 mV/decade and is selective with respect to other L-amino acids.

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Excision GO-CFAR Detectors (Excision GO-CFAR 검출기)

  • 한용인;김태정
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.29B no.1
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    • pp.50-57
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    • 1992
  • This paper proposes and analyzes a new CFAR(Constant False Alarm Rate) detector called the EXGO(Excision Greatest Of)-CFAR. This is the combination of the EXCA(Excision Cell Averaging)-CFAR that shows a good performance under the influence of interferences and the GO(Greatest Of)-CFAR that fights well with clutter edges. For the performance analysis, the formulas for the detection probability and the false alarm probability are derived and computed, and the results are compared with other existing CFAR detectors. Our analysis shows that the proposed EXGO-CFAR considerably improves the false-alarm-rate performance of the EXCA-CFAR at clutter edges while maintaining the high detection probability performance of the EXCA-CFAR in the homogeneous and/or interference noise environment.

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Implementation of Software Platform for STBC-OFDM based WiBro Systems (STBC-OFDM 기반의 WiBro 시스템 소프트웨어 플랫폼 구현)

  • Bae, Jung-Nam;Oh, Young-Chul;Yoo, Sang-Hoon;Wi, Hynn-Ho;Kim, Jin-Young
    • 한국정보통신설비학회:학술대회논문집
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    • 2008.08a
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    • pp.525-530
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    • 2008
  • There are a few core technologies to enable high-performance $4^{th}$ generation (4G) broadband wireless communication system. A multiple input multiple output (MIMO) provides high-rate transmission through expended channels by multiple array antennas in both sender and receiver side. Also orthogonal frequency division multiplexing (OFDM) is well-known as the most appropriate technique for high data rate transmission such as Mobile WiMAX and WLAN. Efficient decrease of inter-carrier interference (ISI) and inter-carrier interference (ICI) are the reasons for why OFDM is suitable for high-performance transmission, 4G mobile communication. In this paper, we mainly focus on two of objects, combination between MIMO and OFDM, and OFDM channel simulator using Ray-tracing algorithm. The results of this paper can be used implementation of a Wireless Software Platform for 4G Mobile Communication Systems.

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