• Title/Summary/Keyword: Noise Elimination

Search Result 227, Processing Time 0.024 seconds

A study on the development of the force-platform system for ground reaction force analysis (지면 반력 분석을 위한 압력판 시스템 개발에 관한 연구)

  • 최혁재;이언주;김문화;장동식
    • Journal of the Ergonomics Society of Korea
    • /
    • v.14 no.2
    • /
    • pp.75-85
    • /
    • 1995
  • The purpose of this study is to develop a force-platform system suitable for real situations in industry. The developed system is a 3-axis measurement type. It consists of force-transmission, force measuring circuit, and the software that analyzes the measured force. The force-transmission transmits forces to 3 axes, which has a physical structure to minimize the interference among those axes. Force measuring circuit consists of DSP (digital signal processor) for flexible disposal of change of measurement algorithm, elimination of noise and maintenance of precision. The functions of the software are the calibration which revises the measurement error occuring during data acquisition, and various analyses of forces. The result of the experiment shows that the developed system has about 1% measurement error, is stable for repeated experiments, and is not effected by temperature change.

  • PDF

Study on enhancing the ultrasonic image for bone densitometry (골밀도 측정을 위한 초음파 영상 개선에 관한 연구)

  • Shin, Jung-Sik;Ahn, Jung-Hwan;Kim, Hyung-Joon;Kim, Hwa-Young;Han, Seung-Moo
    • Journal of the Korean Society for Precision Engineering
    • /
    • v.22 no.8 s.173
    • /
    • pp.182-191
    • /
    • 2005
  • It is very important to obtain a high quality of bone image for an accurate ultrasonic measurement of bone mineral density. In this study, we suggested a technique to acquire an optimal image by adapting an acoustic lens and a properly selected ultrasonic probe. Also, we have applied an image processing algorithm with which automatically makes a decision of brightness and contrast of image by generating threshold level, a composition of ultrasonic data, an elimination of noise using modified median filter, and a real time interpolation. We could confirm much improved resolution of bone image with acoustic lens attached to the ultrasonic probe and with the image processing algorithm suggested in this study. Therefore, it became possible to precisely diagnose the osteoprosis using ultrasonic imaging technique.

Korean Character Recognition by the Extraction of Feature Points and Neural Chip Design for its Preprocessing (특징점 추출에 의한 한글 문자 인식 및 전처리용 신경 칩의 설계)

  • 김종렬;정호선;이우일
    • Journal of the Korean Institute of Telematics and Electronics
    • /
    • v.27 no.6
    • /
    • pp.929-936
    • /
    • 1990
  • This paper describes the method of the Korean character recognition by means of feature points extraction. Also, the preprocessing neural chip for noise elimination, smoothing, thinning and feature point extraction has been designs. The subpatterns were separated by means of advanced index algorithm using mask, and recognized by means of feature points classification. The separation of the Korean character subpatterns was abtained about 97%, and the recognition of the Korean characters was abtained about 95%. The preprocessing neural chip was simulated on SPICE and layouted by double CMOS 2\ulcorner design rule.

  • PDF

Parallel Thinniing Algorithm using Weighted-Value (가중치를 이용한 병렬 세선화 알고리즘)

  • Han, Nak-Hee;Rhee, Phil-Kyu
    • Korean Journal of Cognitive Science
    • /
    • v.7 no.1
    • /
    • pp.5-35
    • /
    • 1996
  • This paper addresses an one-pass parallel thinning algorithm which shows effectiveness in both accuracy and speed. The proposed method is based on parallel iterative boundary removal.Image connectivity are preseved and the algorithms performance is compared to other algorithms especially to parallel thinning algorithm which is the best parallel algorithm have been proposed.Evaluation result shows that the proposed algorithm compare favorably to others.The result shows exact thinning free from one pixel boundary noise and free from distortion of shape.

  • PDF

An Algorithm for the Characterization of Surface Crack by Use of Dipole Model and Magneto-Optical Non-Destructive Inspection System

  • Lee, Jin-Yi;Lyu, Sung-Ki;Nam, Young-Hyun
    • Journal of Mechanical Science and Technology
    • /
    • v.14 no.10
    • /
    • pp.1072-1080
    • /
    • 2000
  • Leakage magnetic flux (LMF) is widely used for non-contact detection of cracks. The combination of optics and LMF offers advantages such as real time inspection, elimination of electrical noise, high spatial resolution, etc. This paper describes a new nondestructive evaluation method based on an original magneto-optical inspection system, which uses a magneto-optical sensor, LMF, and an improved magnetization method. The improved magnetization method has the following characteristics: high observation sensitivity, independence of the crack orientation, and precise transcription of the geometry of a complex crack. The use of vertical magnetization enables the visualization of the length and width of a crack. The inspection system provides the images of the crack, and shows a possibility for the computation of its depth.

  • PDF

English Character Recognition and Design of Preprocessing Neural Chip (영문자 인식 및 전처리용 신경칩의 설계)

  • 남호원;정호선
    • The Journal of Korean Institute of Communications and Information Sciences
    • /
    • v.15 no.6
    • /
    • pp.455-466
    • /
    • 1990
  • Enalish character recognition with the neural networl algorithm has been performed. Character recognition technition techniques which are processed by software, have the limit of the recognition speed. To overcome this limit, we realize this system to hardware by using the neural network algorithm. We have designed preprocessing chip using the neural nework model, that is single layer perceptorn, in the noise elimination, smoothing, thinning and feature point extraction. These chips are implemented as a CMOS double metal 2um design rule.

  • PDF

An experimental research on the heating characteristics and the elimination of noise in electric ondol for off-peak storage use (축열형 전기온돌의 난방특성과 진동소음 제거에 관한 실험적 연구)

  • 현경호;오명환;채성기
    • 전기의세계
    • /
    • v.22 no.2
    • /
    • pp.75-86
    • /
    • 1973
  • 본 연구에서는 전기온돌의 안방열손실을 감소시키고 축열효과를 향상시키기 위한 방법을 검토하였으며 전기온돌에서 발생하는 진동소음을 감살시킬 수 있는 대책을 제시하였다. 저육들은 6.6[m$^{2}$] 크기의 전기온돌 model을 이용하여 건물의 구조차이와 하향열단열층의 설치유무에 따른 보온특성의 차이를 기록분석하였으며 그 결과 열전도계수가 0.03[kcal/m.hr.deg. C]정도인 내열성 Styropol과 지석 Mortar로 구성된 하향열단열층을 전기온돌의 마닥에 설치할 경우 난방부하의 감소로 인하여 축열효율이 약 2배나 향상된다는 결론을 얻었다. 또한 전기온돌공사시에 발열선을 지지할 수 있는 대각선형 Spacer를 설치하고 발열선이 매설콘크리트가 완전히 양생된 이후에 전력을 인가하면 흔히 전기온돌에서 발생하는 120-960[Hz]의 가청진동소음을 방지할 수 있다는 사실을 실험적으로 확인하였다.

  • PDF

A Design of Real Time Measurement System for EMG Silent Period Under Window Base (윈도우 환경하에서 근전도의 실시간 Silent Period 측정 시스템 설계)

  • 강병길;김태훈;이영석;김덕영;김세동;김성환
    • The Transactions of the Korean Institute of Electrical Engineers D
    • /
    • v.52 no.10
    • /
    • pp.611-617
    • /
    • 2003
  • A mechanical or electrical stimulation to the mandibular symphysis during a maximal voluntary clenching of the teeth always produces a jaw jerk followed by a silent period (transient stops) in the masseteric EMG (electromyogram). Generally, a mechanical stimulation is followed by a single silent period, and an electrical stimulation is followed by multiple silent periods. In this paper, we propose a new algorithm for determining the duration of the masseter silent period. The decision approach in essentially based upon a segmentation algorithm consisted of variance filter, median filter and gaussian filter. The new adaptive digital notch filter using R-CLMS(reverse constrained least mean-squared) algorithm is proposed for the elimination of powerline(60Hz) noise. At the same time, we design a real time measurement system for the EMG silent period under Window base.

Sketch Feature Point Extraction using Hierarchical Knowledge-based Noise Elimination (계층적 지식기반 잡음제거를 이용한 스케치 특징점 검출)

  • Cho, Sun-Young;Byun, Hye-Ran
    • Proceedings of the Korean Information Science Society Conference
    • /
    • 2008.06c
    • /
    • pp.498-502
    • /
    • 2008
  • 본 논문에서는 스케치 보정을 위한 계층적 지식 기반 잡음 제거 방법을 제안한다. 제안하는 잡음 제거 방법은 방향 정보, 후보 영역간의 내적, 갈고리 잡음영역 검출이라는 세 개의 계층적 휴리스틱(heuristic) 방법으로 구성된다. 첫 번째 단계에서 방향정보를 이용하여 특징점 후보들이 검출되고, 두 번째 단계에서는 각 후보들 사이의 벡터 간 내적을 이용하여 부적절한 후보들이 제거되며, 세 번째 단계에서는 갈고리모양의 잡음영역을 검출하여 근거리에 모여있는 특징점들을 병합한다. 실험을 통해 제안하는 방법이 잡음에 민감한 실제 응용 환경에 적합하며 효율적임을 보였다.

  • PDF

The Evaluation of Effectiveness on Horizontal Ambient Vibration Measurement of Tall Building Using Wireless MEMS Sensor (무선 MEMS 센서를 이용한 초고층 건물 수평 상시진동 계측의 유효성 평가)

  • Lee, Jong-Ho;Cheon, Dong-Jin;Yoon, Sung-Won
    • Journal of Korean Association for Spatial Structures
    • /
    • v.18 no.2
    • /
    • pp.51-58
    • /
    • 2018
  • Recently, measuring instruments for SHM of structures had being developed. In general, the wireless transmission of sensor signals, compared to its wired counterpart, is preferable due to its absence of triboelectric noise and elimination of the requirement for cumbersome cable. However, the research on the tall buildings with relatively small vibration levels is insufficient. Therefore, in this paper, we used the wireless MEMS sensor and iPad to compare and analyze the vibration measurements of three tall buildings and two towers.