Research

• Current research, University of Florida

  • Precision Agriculture Laboratory

  • UF/IFAS PARS (Precision Agriculture and Remote Sensing) Group  

  • Recent Publications

   

   

  2008

  • Lee, W. S., R. Ehsani, and R. Shankar. 2008. Trash detection system for a citrus canopy shake and catch harvester using machine vision. ASABE Paper No. 084249. St. Joseph, Mich.: ASABE.

  • Lehtola, C. J. and W. S. Lee. 2008. U. S. agricultural safety issues and trends. 3^rd Korea-Japan Joint Seminar on “Safety for agricultural machinery”. September, 23, 2008. National Institute of Agricultural Engineering, Rural Development Administration, Suwon, Korea.  

  • Lee, W. S., R. Ehsani, and L. G. Albrigo. 2008. Citrus greening (Huanglongbing) detection using aerial hyperspectral imaging. 9^th International Conference on Precision Agriculture. July 20-23, 2008, Hyatt Regency Tech Center, Denver, Colorado.

  • Lee, W. S. 2008. Precision agriculture: methods and applications. United Nations/Colombia/United States of America Workshop on the Applications of Global Navigation Satellite Systems. Medellin, Colombia, June 23-27, 2008.

  • Lee, W. S., L. Estrada, and R. Espinel. 2008. Precision agriculture in Ecuador. 2008 Florida Section ASABE Annual Conference and Tradeshow. June 12-13, 2008 – Duck Key, Florida.

  • Lee, W. S. 2008. Precision agriculture: methods and possibilities. Invited presentation at Escuela Superior Politécnica del Litoral (ESPOL), March 9-15, Guayaquil, Ecuador.

  • Lee, W. S., R. Chinchuluun, and R. Ehsani. 2008. Citrus fruit identification using machine vision for a canopy shake and catch harvester. International Symposium: “Application of precision agriculture for fruits and vegetables”. January 6-9, 2008. Grosvenor Resort, Orlando, Florida.

  • Chinchuluun, R., Lee, W., Bhorania, J., and Pardalos, P. M.  2008. Clustering and classification algorithms in food and agricultural applications: A survey.  In Papajorgji, P. ed. "Advances in Modeling Agricultural Systems." Berlin: Springer.

  • Lee, W., Bogrekci, I. and Min, M.  2008. Modeling in nutrient sensing for agricultural and environmental applications." In Papajorgji, P. ed. "Advances in Modeling Agricultural Systems. Berlin: Springer.

  • Min, M., W. S. Lee, T. F. Burks, J. D. Jordan, A. W. Schumann, J. K. Schueller, and H. Xie. 2008. Design of a hyperspectral nitrogen sensing system for citrus. Computers and Electronics in Agriculture 63(2): 215-226.

   

  2007

  • Chinchuluun, R., W. S. Lee, and R. Ehsani. 2007. Citrus yield mapping system on a canopy shake and catch harvester. ASABE Paper No. 073050. St. Joseph, Mich.: ASABE.

  • Kane, K. E., and W. S. Lee. 2007. Multispectral imaging for in-field green citrus identification. ASABE Paper No. 073025. St. Joseph, Mich.: ASABE.

  • Okamoto, H., W. S. Lee, and K. E. Kane. 2007. Hyperspectral imaging for green citrus fruit detection. 6^th European Conference in Precision Agriculture and 2^nd European Conference on Precision Livestock Farming, June 3-6, 2007, Skiathos , Greece .

  • Bogrekci, I. and W. S. Lee. 2007. Comparison of Ultraviolet, Visible, and Near Infrared Sensing for Soil Phosphorus. Biosystems Engineering 96(2): 293-299. 

  • Cohen, M. J., R. Mylavarapu, I. Bogrekci, W. S. Lee, and M. W. Clark. 2007. Reflectance Spectroscopy for Routine Agronomic Soil Analyses. Soil Science 172(6): 469-485.  

   

   

  2006

  • Bogrekci, I., and W. S. Lee. 2006. Effects of soil moisture content on absorbance spectra of sandy soils in sensing phosphorus concentrations using UV-VIS-NIR spectroscopy. Trans. ASABE 49(4): 1175-1180.

  • Bogrekci, I., and W. S. Lee. 2006. The effect of particle size on sensing phosphorus by Raman spectroscopy. ASABE Paper No. 063048. St. Joseph, Mich.: ASABE.

  • Chinchuluun, R., and W. S. Lee. 2006. Citrus yield mapping system in natural outdoor scenes using the Watershed transform. ASABE Paper No. 063010. St. Joseph, Mich.: ASABE. 

  • Kane, K. E., W. S. Lee. 2006. Spectral sensing of different citrus varieties for precision agriculture. ASABE Paper No. 061065. St. Joseph, Mich.: ASABE.

  • Min, M., and W. S. Lee. 2006. Design of a hyperspectral nitrogen sensing system for citrus. ASABE Paper No. 061061. St. Joseph, Mich.: ASABE.

  • MacArthur, D. K., J. K. Schueller, W. S. Lee, C. D. Crane, E. Z. MacArthur, and L. R. Parsons. 2006. Remotely-piloted helicopter citrus yield map estimation. ASABE Paper No. 063096. St. Joseph , Mich. : ASABE.

  • Min, M., W. S. Lee, Y. H. Kim, and R. A. Bucklin. 2006. Nondestructive detection of nitrogen in Chinese cabbage leaves using VIS- NIR spectroscopy. HortScience 41(1): 162-166.

  • Pydipati, R., T. F. Burks, and W. S. Lee. 2006. Identification of citrus disease using color texture features and discriminant analysis. Computers and electronics in agriculture 52(1): 49-59.

   

  2005

  • Bogrekci,  I., and W. S. Lee. 2005. Spectral measurement of common soil phosphates. Trans. ASAE. 48(6): 2371-2378.

   

  • Lee, W. S., J. K. Schueller, and T. F. Burks. 2005. Wagon-based silage yield mapping system. Agr. Engng. Intl. Vol. VII. Manuscript IT 05 003, website: cigr-ejournal.tamu.edu. 

   

  • Bogrekci, I. , and W. S. Lee. 2005. Spectral soil signatures and sensing phosphorus. Biosystems Engineering 92(4): 527-533.

  • Pydipati, R., T. F. Burks, and W. S. Lee. 2005. Statistical and neural network classifiers for citrus disease detection using machine vision. Trans. ASAE. 48(5): 2007-2014.

   

  • Bogrekci,  I., and W. S. Lee. 2005. Improving phosphorus sensing by eliminating soil particle size effect in spectral measurement. Trans. ASAE. 48(5): 1971-1978.

   

  • Shin, D. J., W. S. Lee, and S. Y. Na. 2005. Dynamic load estimation in silage harvesting. Trans. ASAE 48(4): 1131-1320. 

   

  • Bogrekci, I., and W. S. Lee. 2005. A Raman sensor for phosphorus sensing in soil and vegetations. ASAE Paper No. 051040. St. Joseph, Mich.: ASAE.

   

  • Bogrekci, I., W. S. Lee, and J. D. Jordan. 2005. Multispectral image analysis for phosphorus measurement in Bahia grass. ASAE Paper No. 051067. St. Joseph, Mich.: ASAE.

   

  • Min, M., and W. S. Lee. 2005. Hyperspectral nitrogen sensing system for citrus. ASAE Paper No. 051068. St. Joseph, Mich.: ASAE.

   

  • Na, S. Y., W. S. Lee, D. J. Shin, J. Y. Kim, and B. H. Lee. 2005. Crop flow measurement using photosensors to reduce disturbance error in yield estimation. ASAE Paper No. 051131. St. Joseph, Mich.: ASAE.

   

  • Regunathan, M., and W. S. Lee. 2005. Citrus yield mapping and size determination using machine vision and ultrasonic sensors. ASAE Paper No. 053017. St. Joseph, Mich. ASAE.

   

  • Sevier, B. J., and W. S. Lee. 2005. Precision farming adoption in Florida citrus: A grower case study. ASAE Paper No. 051054. St. Joseph, Mich.: ASAE.

   

  • Bogrekci, I., W. S. Lee, and J. D. Jordan. 2005. Airborne hyperspectral imaging for sensing phosphorus concentrations in the Lake Okeechobee basins. In Proc. SPIE Defense & Security Symposium, Vol. 5795, p. 106-112, Chemical and Biological Sensing VI. P. J. Gardner ed. March 28-April 1, 2005. Gaylord Palms Resort and Convention Center, Orlando, FL. 

   

  • Bogrekci, I. and W. S. Lee. 2005. Spectral phosphorus mapping using diffuse reflectance of soils and grass. Biosystems Engineering 91(3): 305-312.

   

  • Sevier, B. J., and W. S. Lee. 2005. Precision farming adoption by Florida citrus producers: probit model analysis. UF/IFAS Extension Circular 1461 - DLN AE283.

   

  • Min, M., and W. S. Lee. 2005. Determination of significant wavelengths and prediction of nitrogen content for citrus. Trans ASAE 48(2): 455-461. 

   

  2004

  • Annamalai, P., W. S. Lee, and T. F. Burks. 2004. Color vision system for estimating citrus yield in real-time. ASAE Paper No. 043054. St. Joseph, Mich.: ASAE.

   

  • Annamalai, P., and W. S. Lee. 2004. Identification of green citrus fruits using spectral characteristics. ASAE Paper No. FL04-1001. St. Joseph, Mich.: ASAE.

   

• Bogrekci, I., W. S. Lee, and J. P. Herrera. 2004. Spectral signatures for the Lake Okeechobee soils using UV-VIS-NIR spectroscopy and predicting phosphorus concentrations. ASAE Paper No. 041076. St. Joseph, Mich.: ASAE.

 

• Bogrekci, I., and W. S. Lee. 2004. Spectral signatures of common phosphates in soils and their effect on absorbance spectra of soil samples with different phosphorus concentrations. ASAE Paper No. 043114. St. Joseph, Mich.: ASAE.

 

• Bogrekci, I., and W. S. Lee. 2004. Soil particle size effect on absorbance spectra of sandy soils in UV-VIS-NIR regions. ASAE Paper No. 043112. St. Joseph, Mich.: ASAE.

 

• Bogrekci, I., and W. S. Lee. 2004. Determining phosphorus concentration using spectral reflectance of grass and soil samples in the Lake Okeechobee basins in UV, VIS, and NIR regions. In Proc. 7th International Conference on Precision Agriculture.

 

• Bogrekci, I., and W. S. Lee. 2004. The effects of soil moisture content on reflectance spectra of soils using UV-VIS-NIR spectroscopy. In Proc. 7th International Conference on Precision Agriculture.

 

• Herrera, J. P., W. S. Lee, and I. Bogrekci.  2004. Spectral based phosphorus sensing in the Lake Okeechobee Basin. ASAE Paper No. 041077. St. Joseph, Mich.: ASAE.

 

• Min, M., W. S. Lee, and I. Bogrekci. 2004. The effect of water and variety on nitrogen sensing of citrus leaf. ASAE Paper No. 041080. St. Joseph, Mich.: ASAE.

 

• Lee, W. S., and D. C. Slaughter. 2004. Recognition of partially occluded plant leaves using a modified Watershed algorithm. Trans. ASAE 47(4): 1269-1280.

 

• Sevier, B. J., and W. S. Lee. 2004. Precision agriculture in citrus: a Probit model analysis for technology adoption. ASAE Paper No. 041092. St. Joseph, Mich.: ASAE.

 

• Shoup, W. D., W. S. Lee, and T. Harrison. 2004. Precision technologies for precision management. In Agricultural Systems Management: Optimizing Efficiency and Performance, 245-276. R. M. Peart and W. D. Shoup, eds. New York, N.Y.: Marcel Dekker. 

    2003

• W. S. Lee, J. F. Sanchez, R. S. Mylavarapu, and J.S. Choe. 2003. Estimating chemical properties of Florida soils using spectral reflectance. Trans. ASAE 46(5): 1443-1453

• "Citrus yield mapping system using machine vision", ASAE Paper No. 031002

• "Adoption trends and attitudes towards precision agriculture in Florida citrus: preliminary results from a citrus producer survey", ASAE Paper No. 031100

• "Spectral-based nitrogen sensing for citrus", ASAE Paper No. 031137

• "Assessment of P-concentration in the Lake Okeechobee drainage basins with spectroscopic reflectance of VIS and NIR", ASAE Paper No. 031139

• "Data fusion in yield maps to reduce errors using distinctive types of sensors", ASAE Paper No. 031035

2002

• "Silage yield monitoring system", ASAE Paper No. 021165

• "Temporal Variation of Soil Ca, Mg, and K using Precision Agriculture in Florida ", ASAE Paper No. FL 2002-19.

• "Comparing interpolation methods for mapping soil properties: Ca, Mg, and K", ASAE Paper No. FL 2002-20.

 

2001

• "Study on soil properties and spectral characteristics in Florida", ASAE Paper No. 011179

• Agricultural and Biological Engineering Department

• Texas A&M University

  • Nitrogen sensor for corn plants

    • "Multispectral sensor for detecting nitrogen in corn plants", ASAE Paper No. 00-1010

    • "Assessing nitrogen stress in corn varieties of varying color", ASAE Paper No. 99-3034

  • Precision Agriculture Laboratory

  • Agricultural Engineering Department

• University of California, Davis

  • Robotic weed control system for tomatoes

    • "Robotic weed control system for tomatoes", Precision Agriculture, 1, 95-113 (1999)

    • Ph.D. Dissertation: Robotic weed control system for tomatoes

    • "Robotic weed control system for tomatoes using machine vision system and precision chemical application", ASAE Paper No. 973093

    • International Conference on Agricultural Machinery Engineering Proceedings, 1996, Seoul Korea, vol.3: 802-811.

  • Plant recognition using hardware-based neural network (ASAE Paper No. 983040)

  • Biological and Agricultural Engineering Department

Last modified on October 17, 2008.