Jackson, P. and Knapp, R.S. (2003). Density profiler for
measuring density profile of a medium and method and
apparatus using same. US Patent 6,633,625.

Jampana, P., Shah, S., Kadali, R., and Kihas, D. (2008).
Computer vision based interface level control in a separation cell. IFAC Proceedings, 
41(2), 3298–3303.

Li, B., Xu, F., Ren, Z., and Espejo, A. (2011). Primary
separation vessel interface control. In 2011 International
Symposium on Advanced Control of Industrial Processes
(ADCONIP), 262–264. IEEE.

Shafi, H., Velswamy, K., Ibrahim, F., and Huang, B.
(2020). A hierarchical constrained reinforcement learning for optimization of bitumen recovery 
rate in a primary separation vessel. 
Computers & Chemical Engineering, 106939.

Simon, D. (2006). Optimal State Estimation: Kalman,
H Infinity, and Nonlinear Approaches. John Wiley &
Sonss.

Tu, Y., O’Carroll, J., Kotlyar, L., Sparks, B., Ng, S.,
Chung, K., and Cuddy, G. (2005). Recovery of bitumen
from oilsands: gelation of ultra-fine clay in the primary
separation vessel. Fuel, 84(6), 653–660.

Vicente, A., Raveendran, R., Huang, B., Sedghi, S.,
Narang, A., Jiang, H., and Mitchell, W. (2019). Computer vision system for froth-middlings interface level
detection in the primary separation vessels. Computers
Chemical Engineering, 123, 357–370.

Xie, L., Zhu, Y., Huang, B., and Zheng, Y. (2012). Kalman
filtering approach to multirate information fusion for
soft sensor development. In 2012 15th International
Conference on Information Fusion, 641–648.