DOI QR코드

DOI QR Code

한국 하천의 지역별 유사특성의 군집화와 H-ADCP 기반 부유사 농도 관측 기법에의 활용 방안

Clustering of sediment characteristics in South Korean rivers and its expanded application strategy to H-ADCP based suspended sediment concentration monitoring technique

  • 노효섭 (서울대학교 건설환경공학부) ;
  • 손근수 (한국수자원조사기술원 첨단인프라실) ;
  • 김동수 (단국대학교 토목환경공학과) ;
  • 박용성 (서울대학교 건설환경공학부)
  • Noh, Hyoseob (Department of Civil and Environmental Engineering, Seoul National University) ;
  • Son, GeunSoo (Advanced Infra Division, Korea Institute of Hydrological Survey) ;
  • Kim, Dongsu (Department of Civil and Environmental Engineering, Dankook University) ;
  • Park, Yong Sung (Department of Civil and Environmental Engineering, Seoul National University)
  • 투고 : 2021.11.08
  • 심사 : 2021.12.06
  • 발행 : 2022.01.31

초록

유사량 계측 기술의 발달로 초음파 도플러 유속계(ADCP)의 산란도가 부유사 농도와 관계가 있다는 특성을 이용해 부유사의 농도를 짧은 시간 간격으로 계측하여 부유사 관측의 비용과 위험 문제를 극복하고자 하는 노력이 지속되고 있다. 국내에는 자동 유량 관측소에 횡방향 ADCP (H-ADCP)가 설치되어 있어 실시간으로 부유사 농도를 계측하는 기술의 적용이 가능하지만 자동 유량 관측소와 부유사 관측소의 위치가 항상 일치하지는 않아 모든 관측소에서의 모형 개발은 불가한 실정이다. 본 연구에서는 이러한 문제를 극복하기 위해 H-ADCP가 설치된 유사량 관측소 9개소에 대해 부유사 농도를 계측하는 H-ADCP-SSC 관계식을 개발하고 그 결과의 적용성에 대해 고찰하였다. 그리고 부유사 관측소별로 나타나는 특징에 대해 알아보기 위해 한국 하천의 부유사 관측소 44개소의 유역면적, 부유사와 하상토의 입도분포, 유량-유사량 관계식 등의 유사특성 자료를 이용해 비지도 기계학습 기법인 가우시안 혼합 모형(GMM)으로 군집분석을 수행하였다. 군집화 결과, 유사량 관측소를 공간적으로 구분해낼 수 있었으며, 특히 하천의 본류와 지류의 유사 특징을 구분해낼 수 있었다. 결과적으로, H-ADCP-SSC 관계식과 부유사 관측소의 군집분석 결과를 종합해 H-ADCP-SSC 관계식이 개발되지 않은 자동 유량 관측소에서 관계식을 적용하는 부유사 농도를 실시간으로 계측할 수 있도록 하는 프로토콜을 제안하였다.

Advances in measurement techniques have reduced measurement costs and enhanced safety resulting in less uncertainty. For example, an acoustic doppler current profiler (ADCP) based suspended sediment concentration (SSC) measurement technique is being accepted as an alternative to the conventional data collection method. In Korean rivers, horizontal ADCPs (H-ADCPs) are mounted on the automatic discharge monitoring stations, where SSC can be measured using the backscatter of ADCPs. However, automatic discharge monitoring stations and sediment monitoring stations do not always coincide which hinders the application of the new techniques that are not feasible to some stations. This work presents and analyzes H-ADCP-SSC models for 9 discharge monitoring stations in Korean rivers. In application of the Gaussian mixture model (GMM) to sediment-related variables (catchment area, particle size distributions of suspended sediment and bed material, water discharge-sediment discharge curves) from 44 sediment monitoring stations, it is revealed that those characteristics can distinguish sediment monitoring stations regionally. Linking the two results, we propose a protocol determining the H-ADCP-SSC model where no H-ADCP-SSC model is available.

키워드

과제정보

본 연구는 환경부의 재원으로 한국환경산업기술원의 수요대응형 물공급서비스 연구사업의 지원을 받아 수행되었으며 이에 감사드립니다(2020002650001).

참고문헌

  1. Akaike, H. (1974). "A new look at the statistical model identification." IEEE Transactions on Automatic Control, Vol. 19, No. 6, pp. 716-723. https://doi.org/10.1109/TAC.1974.1100705
  2. Asuero, A.G., Sayago, A., and Gonzalez, A. G. (2006). "The correlation coefficient: An overview." Critical Reviews in Analytical Chemistry, Vol. 36, No. 1, pp. 41-59. https://doi.org/10.1080/10408340500526766
  3. Bishop, C.M. (2006). Pattern recognition and machine learning. springer, New York, U.S.
  4. Colby, B.R., and Hembree, C.H. (1954). "Computations of total sediment discharge, Niobrara River near Cody, Nebraska." Science, Vol. 119, No. 3097, pp. 657-658. https://doi.org/10.1126/science.119.3097.657.b
  5. Dempster, A.P., Laird, N.M., and Rubin, D.B. (1977). "Maximum likelihood from incomplete data via the EM algorithm." Journal of the Royal Statistical Society: Series B (Methodological), Vol. 39, No. 1, pp. 1-22. https://doi.org/10.2307/2347807
  6. Downing, A., Thorne, P.D., and Vincent, C.E. (1995). "Backscattering from a suspension in the near field of a piston transducer." The Journal of the Acoustical Society of America, Vol. 97, No. 3, pp. 1614-1620. doi: 10.1121/1.412100
  7. Flammer, G.H. (1962). Ultrasonic measurement of suspended sediment, (Vol. 1141). US Government Printing Office, Washington, D.C., U.S.
  8. Guerrero, M., Szupiany, R.N., and Latosinski, F. (2013). "Multi-frequency acoustics for suspended sediment studies: An application in the Parana River." Journal of Hydraulic Research, Vol. 51, No. 6, pp. 696-707. https://doi.org/10.1080/00221686.2013.849296
  9. Haught, D., Venditti, J.G., and Wright, S.A. (2017). "Calculation of in situ acoustic sediment attenuation using off the shelf horizontal ADCPs in low concentration settings." Water Resources Research, Vol. 53, No. 6, pp. 5017-5037. https://doi.org/10.1002/2016WR019695
  10. Julien, P.Y. (2010). Erosion and sedimentation. Cambridge University Press, Cambridge, UK.
  11. Landers, M.N. (2012). Fluvial suspended sediment characteristics by high-resolution, surrogate metrics of turbidity, laser-diffraction, acoustic backscatter, and acoustic attenuation. Ph. D. dissertation, Georgia Institute of Technology, GA, US.
  12. Landers, M.N., Straub, T.D., Wood, M.S., and Domanski, M.M. (2016). Sediment acoustic index method for computing continuous suspended-sediment concentrations, No. 3-C5. US Geological Survey, Washington, D.C., U.S.
  13. Lee, C.J., Kim, J.S., Kim, Y.J., and Kim, W. (2010). "Method for estimation of roughness coefficient by field measurement and its application." Proceedings of the Korea Water Resources Association Conference, KWRA, pp. 504-508. (in Korean)
  14. Ministry of Environment (ME) (2019). Hydrological annual report in Korea. (in Korean)
  15. Molinas, A., and Wu, B. (1998). "Effect of size gradation on transport of sediment mixtures." Journal of Hydraulic Engineering, Vol. 124, No. 8, pp. 786-793. https://doi.org/10.1061/(ASCE)0733-9429(1998)124:8(786)
  16. Moore, S.A., Le Coz, J., Hurther, D., and Paquier, A. (2012). "On the application of horizontal ADCPs to suspended sediment transport surveys in rivers." Continental Shelf Research, Vol. 46, pp. 50-63. https://doi.org/10.1016/j.csr.2011.10.013
  17. Schober, P., Boer, C., and Schwarte, L.A. (2018). Correlation coefficients: Appropriate use and interpretation. Anesthesia & Analgesia, Vol. 126, No. 5, pp. 1763-1768. https://doi.org/10.1213/ane.0000000000002864
  18. Schulkin, M., and Marsh, H.W. (1962). "Sound absorption in sea water." The Journal of the Acoustical Society of America, Vol. 34, No. 6, pp. 864-865. 10.1121/1.1918213
  19. Schwarz, G. (1978). "Estimating the dimension of a model." The Annals of Statistics, Vol. 6, No. 2, pp. 461-464. https://doi.org/10.1214/aos/1176344136
  20. Seo, K., Kim, D., and Son, G. (2016) "Estimation of suspended sediment concentration in small stream with acoustic backscatter from horizontal ADCP based on real-scalefield experiment." Journal of Korean Society of Civil Engineers. Vol. 36, No. 6, pp. 1023-1035 (in Korean) https://doi.org/10.12652/Ksce.2016.36.6.1023
  21. Sheng, J., and Hay, A.E. (1988). "An examination of the spherical scatterer approximation in aqueous suspensions of sand." The Journal of the Acoustical Society of America, Vol. 83, No. 2, pp. 598-610. https://doi.org/10.1121/1.396153
  22. Son, G., Kim, D., and Roh, Y.S. (2020). "Development of a Surrogate Technology Load Based upon Horizontal ADCP for continuous estimation of suspended sediment." Proceedings of the Korea Water Resources Association Conference, KWRA, p. 47. (in Korean)
  23. Son, G., Kim, D., Kwak, S., Kim, Y.D., and Lyu, S. (2021). "Characterizing three-dimensional mixing process in river confluence using acoustical backscatter as surrogate of suspended sediment." Journal of Korea Water Resources Association, Vol. 54, No. 3, pp. 167-179. doi: 10.3741/JKWRA.2021.54.3.167 (in Korean)
  24. Topping, D.J., Wright, S.A., Melis, T.S., and Rubin, D.M., (2006). "High-resolution monitoring of suspended-sediment concentration and grain size in the Colorado River using laser-diffraction instruments and a three-frequency acoustic system" Proceedings of the Eighth Federal Interagency Sedimentation Conference, U.S. Geol. Surv., Reno, Nev., pp. 539-546.
  25. Topping, D.J., Wright, S.A., Melis, T.S., and Rubin, D.M. (2007). "High-resolution measurements of suspended-sediment concentration and grain size in the Colorado River in Grand Canyon using a multi-frequency acoustic system." Proceedings 10th International Symposium on River Sedimentation, World Assoc. for Sediment. and Erosion Res., Moscow, Russia, Vol. 3, pp. 330-339.
  26. Urick, R.J. (1948). "The absorption of sound in suspensions of irregular particles." The Journal of the acoustical society of America, Vol. 20, No. 3, pp. 283-289. https://doi.org/10.1121/1.1906373
  27. Urick, R.J. (1975), Principles of underwater sound for engineers, McGraw Hill, NY, U.S., p. 384.
  28. Venditti, J.G., Church, M., Attard, M.E., and Haught, D. (2016). "Use of ADCPs for suspended sediment transport monitoring: An empirical approach." Water Resources Research, Vol. 52, No. 4, pp. 2715-2736. https://doi.org/10.1002/2015WR017348
  29. Wall, G.R., Nystrom, E.A., and Litten, S. (2006). "Use of an ADCP to compute suspended-sediment discharge in the tidal Hudson River." U.S. Geological Survey Scientific Investigations Report 2006-5055, U.S. Geological Survey, Reston, New York, U.S.
  30. Wright, S.A., Topping, D.J., Williams, C.A. (2010). "Discriminating silt-and-clayfrom suspended-sand in rivers using side-looking acoustic profilers." Proceedings of the 2nd Joint Federal Interagency Sedimentation Conference, U.S. Geol. Surv., LasVegas, NV, U.S.