• Journal of Biosystems Engineering
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• 제27권2호
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• pp.133-142
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• 2002

This is a fundamental study to develop a sensor to detect weeds in paddy field using machine vision adopted spectralphotometric technique in order to use the sensor to spread herbicide selectively. A set of spectral reflectance data was collected from dry and wet soil and leaves of rice and 6 kinds of weed to select desirable wavelengths to classify soil, rice and weeds. Stepwise variable selection method of discriminant analysis was applied to the data set and wavelengths of 680 and 802 m were selected to distinguish plants (including rice and weeds) from dry and wet soil, respectively. And wavelengths of 580 and 680 nm were selected to classify rice and weeds by the same method. Validity of the wavelengths to distinguish the plants from soil was tested by cross-validation test with built discriminant function to prove that all of soil and plants were classified correctly without any failure. Validity of the wavelengths for classification of rice and weeds was tested by the same method and the test resulted that 98% of rice and 83% of weeds were classified correctly. Feasibility of CCD color camera to detect weeds in paddy field was tested with the spectral reflectance data by the same statistical method as above. Central wavelengths of RGB frame of color camera were tried as tile effective wavelengths to distingush plants from soil and weeds from plants. The trial resulted that 100% and 94% of plants in dry soil and wet soil, respectively, were classified correctly by the central wavelength or R frame only, and 95% of rice and 85% of weeds were classified correctly by the central wavelengths of RGB frames. As a result, it was concluded that CCD color camera has good potential to be used to detect weeds in paddy field.

• 한국잡초학회지
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• 제9권2호
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• pp.141-148
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• 1989

전국(全國)의 각(各) 지역(地域)에서 채집(採集)한 피는 외부형태적(外部形態的)으로는 매우 큰 차이(差異)를 보였으나 Yabuno가 제시(提示)한 종자(種子)의 포영 길이와 생육습성(生育習性)에 따라 분류(分類)하면 E.oryzicola 와 E.crus-galli var. crus-galli, 및 var. praticola 로 대별(大別)할 수 있었다. E. oryzicola는 외부형태적(外部形態的)으로 벼와 유사(類似)하여 초장(草長)이 비교적 작고 직립형(直立型)으로 까락이 없으며 출수기(出穗期)가 대체로 늦은 편이었고 종내변이(種內變異)가 적었다. 그러나 E. crus-galli var. crus-galli 와 var. praticola는 외부형태적(外部形態的)으로 다양(多樣)한 차이(差異)를 보이고 있어서 외부형태(外部形態)만으로 분류(分類)가 어려웠다. E. crus-galli var. crus-galli의 초장(草長), 분얼수(分蘖數), 수수장(穗穗長) 등(等)의 변이폭(燮異幅)이 매우 컸고 E. crus-galli var. praticola 도 비슷한 경향(傾向)을 나타내었다. 우리나라에 분포(分布)하는 피는 외형(外形)의 차이(差異)가 다양(多樣)함에도 불구하고 3정내외(種內外)로 분류(分類)되고 있으며 금후 세포학적(細胞學的)또는 생화학적(生化學的) 관찰(觀察)을 통(通)해 확정(確定)될 수 있을 것이다. 피 3종(種)의 제초제(除草劑)에 대(對)한 반응(反應)은 종내(種內)또는 종간(種間)에서 공(共)히 조사(調査)되었으며 상대적(相對的) 내성(耐性)과 감수성(感受性)의 차이(差異)를 확인할 수 있었다.