Textile Science and Engineering (한국섬유공학회지)

The Korean Fiber Society (한국섬유공학회)
권호 표지

Derivation of Covariance-Length Function for Nonwoven Uniformity(I) -1- D Signal Case-

부직포 균제도 해석을 위한 공분산-시장 함수의 유도(I) -1차원 영상 신호의 경우-

  • Kim Jooyong (Department of Textile Engineering, Soongsil University)
  • Published : 2004.12.01
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Abstract

A method is introduced for deriving the 'covariance length curve (Cov-L)' from the existing variance length curve. Some critical information hidden in existing variance length curve will be revealed through the Cov-L derived. It includes the correlation between any arbitrary measurement lengths, which is not readily available from the variance length curve but that is critical. Correlation functions of arbitrary measurement lengths are derived directly from the variance length curve given without requiring any further information. Use of the correlation functions has more advantages over the traditional V-L curves. First, they represent a yarn diameter (or mass) profile both in scale (resolution) and frequency (periodicity) rather than in scale only which is the case for V-L curves. Second, periodicities hidden in seemingly irregular signals are easily detected and revealed by the correlation functions. It is also beneficiary that the functions are readily available from a V-L curve without further efforts for measurement and analysis.

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References

  1. C. Roedel and S. S. Ramkumar, 'Surface and Mechanical Property Measurements of H1 Technology Needle-Punched Nonwovens', Text. Res. J., 73, 381-385(2003) https://doi.org/10.1177/004051750307300502
  2. A. Cherkassky, 'Evaluating Nonwoven Fabric Irregularity on the Basis of Linnik Functionals', Text. Res. J., 69, 701-708 (1999) https://doi.org/10.1177/004051759906901001
  3. B. Pourdeyhimi and L. Kohel, 'Area-Based Strategy for Determining Web Uniformity', Text. Res. J., 72, 1065-1072 (2002) https://doi.org/10.1177/004051750207201205
  4. I. Krucinska and S. Krucinski, 'Evaluating Fibrous Architecture of Nonwovens with Computer-assisted Microscopy', Text. Res. J., 69, 363-369(1999) https://doi.org/10.1177/004051759906900510
  5. Manual for Online Weight Gauging, NDC Infrared Engineering, 2003
  6. D. Bishop, 'Fabrics: Sensory and Mechanical Properties', Textile Progress, 26, 35-40(1994)
  7. M. Bona, 'Textile Quality', 239-272, Eurotex, 1994
  8. B. Pourdeyhimi, 'Measuring Fiber Orientation in Nonwovens: Part III: Fourier Transform', Text. Res. J., 67, 143-151(1997) https://doi.org/10.1177/004051759706700211
  9. E. Vanmarcke, 'Random Fields: Analysis and Synthesis', pp.185-187, MIT Press, 1983