2Ehsani M R, Upadhyaya S K, Fawcett W R. Feasibility of detecting soil nitrate content using a mid-infrared technique. Transactions of the ASAE,2001,44(6):1931-1940.
3Shibusawa S, Mingzan Li, Sakai K. On-line real-time nir soil sensor. Proceedings of International Conference on Agricultural Engineering (99-ICAE), V -115.
4Rhoades J D,Shouse P J, Alves N A. Determining soil salinity from soil electrical conductivity using different models and estimates. Soil Science Society of America Journal, 1990,54 : 46- 54.
5Wang N, Zhang N, Dowell F E. Design of an optical weed sensor using plant spectral characteristics. Transactionsof the ASAE;2001,44(2):409-419.
6Sugiura R, Noguchi N, Ishii K. Development of remote sensing system using an unmanned helicopter. Journal of the Japanese Society of Agricultural Machinery, 2002,65 (1) : 53- 61.
7Natsuga M, Kawamura S, Itoh K. Effects of wavelength range and light path length on the accuracy of the constituent analysis of un-homogenized milk using near infrared spectroscopy. Journal of the Japanese Society of Agricultural Machinery, 2002,64(5):83- 88.
