• Title/Summary/Keyword: filter interval

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Efficient Implementation of FMCW Radar Signal Processing Parts Using Low Cost DSP (저가형 DSP를 사용하는 FMCW 레이더 신호처리부의 효율적 구현 방안)

  • Oh, Woojin
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.4
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    • pp.707-714
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    • 2016
  • Active driving safety systems for vehicle, such as the front collision avoidance, lane departure warning, and lane change assistance, have been popular to be adopted to the compact car. For improving performance and competitive cost, FMCW radar has been researched to adopt a phased array or a multi-beam antenna, and to integrate the front and the side radar. In this paper we propose several efficient methods to implement the signal processing module of FMCW radar system using low cost DSP. The pulse width modulation (PWM) based analog conversion, the approximation of time-eating functions, and the adoption of vector-based computation, etc, are proposed and implemented. The implemented signal processing board shows the real-time performance of 1.4ms pulse repetition interval (PRI) with 1024pt-FFT. In real road we verify the radar performance under real-time constraints of 10Hz update time.

COASTLINE DETECTION USING COHERENCE MAP OF ERS TANDEM DATA

  • Kim, Myung-Ki;Park, Jeong-Won;Choi, Jung-Hyun;Jung, Hyung-Sup
    • Proceedings of the KSRS Conference
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    • v.1
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    • pp.368-371
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    • 2006
  • A coastline is the boundary between land and ocean masses. Knowledge of coastline is essential for autonomous navigation, geographical exploration, coastal erosion monitoring and modelling, water line change, etc. Many methods have been researched to extract coastlines from the synthetic aperture radar (SAR) and optic images. Most methods were based on the intensity contrast between land and sea regions. However, in these methods, a coastline detection task was very difficult because of insufficient intensity contrast and the ambiguity in distinguishing coastline from other object line. In this paper, we propose an efficient method for the delineation of coastline using interferometric coherence values estimated from ERS tandem pair. The proposed method uses the facts that a tandem pair of ERS is acquired from a time interval of an accurate day and that the coherent and incoherent values in coherence map are land and water, respectively. The coherence map was generated from ERS tandem pair, filtered by MAP filter, and divided into land and water by the determination of threshold value that is based on the bimodality of the histogram. Finally, a coastline was detected by delineating the boundary pixels. There was a good visual match between the detected coastline and the manually contoured line. The interferometric coherence map will be helpful to identify land and water regions easily, and can be used to many applications that are related with a coastline.

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Microarray Data Retrieval Using Fuzzy Signature Sets (퍼지 시그너쳐 집합을 이용한 마이크로어레이 데이터 검색)

  • Lee, Sun-A;Lee, Keon-Myung;Ryu, Keun-Ho
    • Journal of the Korean Institute of Intelligent Systems
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    • v.19 no.4
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    • pp.545-549
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    • 2009
  • Microarray data sets could contain thousands of gene expression levels and have been considered as an important source from which meaningful patterns could be extracted for further analysis in biological studies. It is sometimes necessary to retrieve out specific genes or samples of analyst's interest in an effective way. This paper is concerned with a method to make use of fuzzy signature set in order to filter out genes or samples which satisfy complicated constraints as well as simple ones. Fuzzy signatures are an extension of vector valued fuzzy sets, in which elements of the vector are allowed to have a vector. Fuzzy signature sets are similar to fuzzy signatures except that their leaf elements are fuzzy sets defined on the interval [0,1]. This paper introduces an extension of fuzzy signature sets which specifies aggregation operators at each internal node and comparison operators for aggregation. It also shows how to use the extended fuzzy signature sets in microarray data retrieval and some examples of its usage.

Design of a Variable Sampling Rate Tracking Filter for a Phased Array Radar (위상배열 레이다를 위한 가변 표본화 빈도 추적 필터의 설계)

  • Hong, Sun-Mog
    • Journal of Sensor Science and Technology
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    • v.1 no.2
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    • pp.155-163
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    • 1992
  • The phased array antenna has the ability to perform adaptive sampling by directing the radar beam without inertia in any direction. The adaptive sampling capability of the phased array antenna allows each sampling time interval to be varied for each target, depending on the acceleration of each target at any time. In this paper we design a three-dimensional adaptive tracking algorithm for the phased array radar system with a given set of measurement parameters. The tracking algorithm avoids taking unnecessarily frequent samples, while keeping the angular prediction error within a fraction of antenna beamwidth so that the probability of detection will not be degraded during a track update illuminations. In our algorithm, the target model and the sampling rate are selected depending on the target range and the target maneuver status which is determined by a maneuver detector. A detailed simulation is conducted to test the validity of our tracking algorithm for encounter geometries under various conditions of maneuver.

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OPTICAL PROPERTIES OF SEA WATER IN THE JAPAN SEA (동해 북동해역에서의 해수의 광학적 성질)

  • YANG Yong Rhim
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.10 no.3
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    • pp.173-177
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    • 1977
  • Optical properties were studied in the Japan Sea based on the optical observations in nine oceanographic stations from September 28 to October 2, 1976. Submarine light intensity was measured by using a submarine illuminometer (RIGO, Type: 2501-A) : equipped with a filter(RIGO, Type:V-R-60, wavelength: 600-620nm). In the upper 40 m depth layer light intensity was measured at 1 m depth interval. The absorption coefficient for red color in the area ranged from 0.142 to 0.323 (mean 0.232) : the Secchi-disc depth in the area ranged from 15 to 23 meters (mean 19.8 meters). The relation ship between absorption coefficient (m) am transparency depth (D) was m =4.93/D. The rates of light penetration for red color at three different depths are computed with reference to the surface light intensity At tile depths of 5 m, 10 m and 20 m, the rates of light penetration were $23.11\%(15-34.2\%),\;6.49\%(3.04-12\%)\;and\;0.698\%(0.113-1.27\%)$ respectively.

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High Quality Audio Watermarking using Spread Spectrum and Psychoacoustic Model (대역확산과 심리음향 모델을 이용한 고음질 오디오 워터마킹)

  • Noh Jin-Soo;Rhee Kang-Hyeon
    • Journal of the Institute of Electronics Engineers of Korea CI
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    • v.43 no.5 s.311
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    • pp.48-56
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    • 2006
  • In this paper, we proposed the high quality audio watermarking algorithm using MDCT/IMDCT (Modified DCT/Inverse Modified DCT) with psychoacoustic model. Generally, a digital audio watermark is embedding the frequency domain after frequency transform of the digital audio data but the digital audio quality is affected by watermarking. In our scheme, the digital audio data is spread with PN((Pseudo Noise) code and then audio watermark is embedded in MDCT processing that refers psychoacoustic model. In MDCT processing, according to the shape of filter bank output, the block switching selects a window sequence that has 256, 1,024 or 2,048 points interval for high quality audio. The author confirm that when watermark weight ${\alpha}$ is 2.5 below, the detection ratio of watermark is a satisfied to SDMI's(Secure Digital Music Initiative) recommendation 50% above and SM is $50{\sim}68dB$ range with mainly 4 kind of attacks(Compression, Cropping, FFT and Echo).

Digital Particle Holographic System for Flow-Field Measurements (유동장 계측을 위한 디지털 입자 홀로그래피 시스템)

  • Yan, Yang;Kang, Bo-Seon
    • Transactions of the Korean Society of Mechanical Engineers B
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    • v.34 no.3
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    • pp.309-316
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    • 2010
  • In this study, a digital particle holographic system and its application to channel-flow measurements were investigated. A double-exposure hologram recording system that is capable of recording digital holograms in a short time interval was developed. A correlation coefficient method was used to determine the focal plane of particles. The Wiener filter was used to remove noises and improve image quality. Two-threshold and image segmentation methods were used for binary image transformation. The cross-correlation method was used for particle pairing. The developed system was employed to study channel flow fields, and the axial velocities of channel flow were measured. The measurement errors are acceptable, and this proves the feasibility of using the digital particle holographic system as a good tool for flow-field measurements.

Integrated editing system for 3D stereoscopic contents production (3차원 입체 콘텐츠 제작을 위한 통합 저작 시스템)

  • Yun, Chang-Ok;Yun, Tae-Soo;Lee, Dong-Hoon
    • Journal of Korea Society of Industrial Information Systems
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    • v.13 no.1
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    • pp.11-21
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    • 2008
  • Recently, it has shown an increased interest in 3D stereoscopic contents due to the development of the digital image media. Therefore, many techniques in 3D stereoscopic image generation have being researched and developed. However, it is difficult to generate high immersion and natural 3D stereoscopic contents, because the lack of 3D geometric information imposes restrictions in 2D image. In addition, control of the camera interval and rendering of the both eyes must be repetitively accomplished for the stereo effect being high. Therefore, we propose integrated editing system for 3D stereoscopic contents production using a variety of images. Then we generate 3D model from projective geometric information in single 2D image using image-based modeling method. And we offer real-time interactive 3D stereoscopic preview function for determining high immersion 3D stereo view. And then we generate intuitively 3D stereoscopic contents of high-quality through a stereoscopic LCD monitor and a polarizing filter glasses.

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Association between taste perception, nutrient intake, and mental health in young Japanese women

  • Okayama, Tomoko;Watanabe, Hiroko
    • Nutrition Research and Practice
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    • v.13 no.1
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    • pp.41-46
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    • 2019
  • BACKGROUND/OBJECTIVES: Taste perception is influenced by both nutritional factors and psychological factors. This study was undertaken to measure the 4 basic taste perceptions, nutrient intake, and mental health, and to examine the factors that affect insensitive taste perception in young Japanese women. SUBJECTS/METHODS: Young women in their late teens and twenties were enrolled as subjects. Taste perception was measured by applying the filter-paper disc method over areas of the chorda tympani nerve. Nutritional status was evaluated using brief, self-administered diet history questionnaires. The index of nutritional status was based on the 2015 Japanese dietary reference intakes. Mental health was assessed using the Japanese translation of the Profile of Mood States short version. This study was approved by the ethical committee at Osaka University. RESULTS: The normal taste perception group (four basic tastes [sweet, salty, sour, and bitter] identified as normal taste perception) comprised 55.4% of the subjects, while the abnormal taste perception group (more than 1 abnormal taste perception was perceived, regardless of flavor) comprised 44.6% of the subjects. There were no significant differences in nutrient intake (except manganese) and mental health between the normal and abnormal taste perception groups. Subjects who took 5 mg to less than 7.1 mg zinc per day were at significantly decreased risk of insensitive taste perception compared to subjects who consumed less than 5 mg zinc per day [Regression coefficient 0.831, 95% confidence interval 0.694-0.996]. CONCLUSION: The present results suggest that insensitive taste perception could be associated with zinc deficiency in young women in their late teens and twenties.

Real-Time Traffic Information Provision Using Individual Probe and Five-Minute Aggregated Data (개별차량 및 5분 집계 프로브 자료를 이용한 실시간 교통정보 제공)

  • Jang, Jinhwan
    • The Journal of The Korea Institute of Intelligent Transport Systems
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    • v.18 no.1
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    • pp.56-73
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    • 2019
  • Probe-based systems have been gaining popularity in advanced traveler information systems. However, the high possibility of providing inaccurate travel-time information due to the inherent time-lag phenomenon is still an important issue to be resolved. To mitigate the time-lag problem, different prediction techniques have been applied, but the techniques are generally regarded as less effective for travel times with high variability. For this reason, current 5-min aggregated data have been commonly used for real-time travel-time provision on highways with high travel-time fluctuation. However, the 5-min aggregation interval itself can further increase the time-lags in the real-time travel-time information equivalent to 5 minutes. In this study, a new scheme that uses both individual probe and 5-min aggregated travel times is suggested to provide reliable real-time travel-time information. The scheme utilizes individual probe data under congested conditions and 5-min aggregated data under uncongested conditions, respectively. As a result of an evaluation with field data, the proposed scheme showed the best performance, with a maximum reduction in travel-time error of 18%.