• Title/Summary/Keyword: Sampling Rate

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Multi-Resolution Kronecker Compressive Sensing

  • Canh, Thuong Nguyen;Quoc, Khanh Dinh;Jeon, Byeungwoo
    • IEIE Transactions on Smart Processing and Computing
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    • v.3 no.1
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    • pp.19-27
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    • 2014
  • Compressive sensing is an emerging sampling technique which enables sampling a signal at a much lower rate than the Nyquist rate. In this paper, we propose a novel framework based on Kronecker compressive sensing that provides multi-resolution image reconstruction capability. By exploiting the relationship of the sensing matrices between low and high resolution images, the proposed method can reconstruct both high and low resolution images from a single measurement vector. Furthermore, post-processing using BM3D improves its recovery performance. The experimental results showed that the proposed scheme provides significant gains over the conventional framework with respect to the objective and subjective qualities.

Analysis Technique for the Vibration Signal of Revolution Machine Using the STFT (STFT를 이용한 회전체의 진동신호 분석 기법)

  • Park, Jong-Yeun;Park, Jun-Yong;Choi, Won-Ho
    • Journal of Industrial Technology
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    • v.24 no.A
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    • pp.67-73
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    • 2004
  • The purpose of this study is to analyze the vibration signal of the revolution machine using the STFT(Short Time Fourier Transform). It is common to analyze the frequency of signal through FFT algorithm with the fixed sampling rate. However, in this situation the order spectrum information useful rather than the general frequency information with the fixed sampling rate. In this paper, the resampling technique was used for getting the information of order spectrum. In resampling process, the arithmetic amount and MSE(Mean Square Error) for various kinds of the signal interpolation was compared and presented the propriety of the interpolation method while developing analysis equipment. Order tracking was implemented using signal interpolation method which it has selected. Then the analyzed results were obtained through simulation using the STFT technique.

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Economic-Statistical Design of Adaptive Moving Average (A-MA) Control Charts (적응형 이동평균(A-MA) 관리도의 경제적-통계적 설계)

  • Lim, Tae-Jin
    • Journal of Korean Institute of Industrial Engineers
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    • v.34 no.3
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    • pp.328-336
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    • 2008
  • This research proposes a method for economic-statistical design of adaptive moving average (A-MA) charts. The basic idea of the A-MA chart is to accumulate previous samples selectively in order to increase the sensitivity. The A-MA chart is a kind of adaptive chart such as the variable sampling size (VSS) chart. A major advantage of the A-MA chart over the VSS chart is that it is easy to maintain rational subgroups by using the fixed sampling size. A steady state cost rate function is constructed based on Lorenzen and Vance (1986) model. The cost rate function is optimized with respect to five design parameters. Computational experiments show that the A-MA chart is superior to the VSS chart as well as to the Shewhart $\bar{X}$ chart in the economic-statistical sense.

Temporal interpolator based on spatial filtering (공간 필터링에 근거한 시간축 내삽기)

  • 김종훈
    • Journal of the Korean Institute of Telematics and Electronics B
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    • v.33B no.8
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    • pp.60-67
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    • 1996
  • In this paper, we propose a new temporal interpolation method based on spatial filtering. Compared with the conventional method, the proposed one may use a few adjacent frames and apply temporal lowpass filtering. To develop this method, we follow the basic approach of sampling rate conversion. Additionally, we use some assumption of video sequence : moving object has constant velocity rigid translational motion. From them, spatial filtering for temporal sampling rate conversion is described. This method has a lot of noise immunity on a motion vector and doesn't make a great difference from the original frame. The interpolated frame shows moderate change even there is a great time difference. This method has exactly same description of motion adaptive spatial filter which has an efficient temporal band-limiting characteristics. It imposes the possibility to make video sequence with good pictural quality.

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압축센싱 기반의 무선통신 시스템

  • Reu, Na-Tan;Sin, Yo-An
    • The Magazine of the IEIE
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    • v.38 no.1
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    • pp.56-67
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    • 2011
  • As a result of quickly growing data, a digital transmission system is required to deal with the challenge of acquiring signals at a very high sampling rate, Fortunately, the CS (Compressed Sensing or Compressive Sensing) theory, a new concept based on theoretical results of signal reconstruction, can be employed to exploit the sparsity of the received signals. Then, they can be adequately reconstructed from a set of their random projections, leading to dramatic reduction in the sampling rate and in the use of ADC (Analog-to-Digital Converter) resources. The goal of this article is provide an overview of the basic CS theory and to survey some important compressed sensing applications in wireless communications.

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A Study on Factors Influencing P-wave Velocity of Concrete (콘크리트의 P파 속도에 영향을 주는 인자에 관한 연구)

  • 이광명;이회근;김동수;김지상
    • Proceedings of the Korea Concrete Institute Conference
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    • 1998.10b
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    • pp.725-730
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    • 1998
  • Recently, non-destructive tests are getting popular in evaluating concrete properties without braking specimens. Among several NDT methods, P-wave velocity measurement technique has been widely used to evaluate the stiffness and strength of concrete. The purpose of this study is to investigate factors influencing P-wave velocity measured by impact-resonant method and ultrasonic pulse velocity method, such as moisture content of concrete, existence and size of coarse aggregates, sensor and sampling rate. Test results show that rod-wave velocity measured by impact-resonant method and ultrasonic pulse velocity are significantly affected by the moisture content of concrete, i.e., the lower moisture content, the lower velocity. Moisture content influences rod-wave velocity stronger than ultrasonic pulse velocity. Rod-wave velocity is faster in concrete than in mortar and is also faster in concrete containing small size aggregates. Sensor and sampling rate have little influence on velocity.

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Dynamic Visual Servoing of Robot Manipulators (로봇 메니퓰레이터의 동력학 시각서보)

  • Baek, Seung-Min;Im, Gyeong-Su;Han, Ung-Gi;Guk, Tae-Yong
    • The Transactions of the Korean Institute of Electrical Engineers D
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    • v.49 no.1
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    • pp.41-47
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    • 2000
  • A better tracking performance can be achieved, if visual sensors such as CCD cameras are used in controling a robot manipulator, than when only relative sensors such as encoders are used. However, for precise visual servoing of a robot manipulator, an expensive vision system which has fast sampling rate must be used. Moreover, even if a fast vision system is implemented for visual servoing, one cannot get a reliable performance without use of robust and stable inner joint servo-loop. In this paper, we propose a dynamic control scheme for robot manipulators with eye-in-hand camera configuration, where a dynamic learning controller is designed to improve the tracking performance of robotic system. The proposed control scheme is implemented for tasks of tracking moving objects and shown to be robust to parameter uncertainty, disturbances, low sampling rate, etc.

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On Reducing Estimation Error Caused by Variable Sampling Rate

  • Yoon, Gi-Bum;Yoon, Dong-Uk;Hanseok Ko
    • Proceedings of the IEEK Conference
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    • 2000.07b
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    • pp.1080-1083
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    • 2000
  • In this paper, we show that a variation in sampling rate give rise to system performance degradation and propose a method to effectively reduce the error. We first capture the variation as a first order autoregressive (AR) model and project it as an additional sensor measurement noise. By considering that the sensor measurements include correlated noise, we perform a decorrelation process and then apply a standard Kalman filter (SKF) to estimate the target-state. As a result of the two-step procedure, we achieve a significant reduction in the target state estimation error.

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Development of MRI gradient waveform generator using DSP (DSP를 이용한 자기공명영상의 경사자계 파형 발생기 개발)

  • Ko, K.H.;Kwon, E.S.;Song, Y.C.;Kim, H.J.;Yim, C.Y.;Ahn, C.B.
    • Proceedings of the KIEE Conference
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    • 1999.07g
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    • pp.3147-3149
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    • 1999
  • In this paper, we develop a TMS320C31- 60 DSP board to generate spiral gradient waveforms for Spiral imaging, one of the ultra fast MRI methods. In Spiral imaging, accurate gradient waveforms are very important to acquire high quality image. For this purpose, sampling rate for generating the gradient waveforms is set twice as high as the data sampling rate. With the developed DSP board accurate gradient waveforms are obtained. Ultra fast MR image with the developed DSP board is currently under development.

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Investigating Wastewater Flow Characteristics - O and M Treatment Basins of A City - (처리분구별 하수발생 특성 조사 - A시 O, M 처리분구 -)

  • Hwang, Byung-Gi
    • Journal of Korean Society of Water and Wastewater
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    • v.19 no.3
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    • pp.348-356
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    • 2005
  • Water quality sampling surveys and continuous measurement of flow were conducted to identify wastewater flow characteristics for representative catchment of O and M treatment basins in A city. For HS-1 station representing commercial area, wastewater flow rises in the beginning of office-working hours, moves up and down within narrow range, and lasts till office-leaving hour, and falls gradually reflecting worker's returning home. However, in HS-2 station representing residential area, wastewater flow has two peaks, which are before office-going hour and after office-leaving hour. In residential area, the flow rate of weekends is higher than that of weekdays because it reflects population, being not contributed to generate wastewater during the working hours of weekdays, stay home and produce wastewater for weekends period. To determine the priority for rehabilitation of sewer system, infiltration rate was computed by dividing infiltration flow by mean diameter and total length of sewer, and HS-1 station ranked the first.