由於現今甚少針對森林地區進行空載光達反射強度值校正之研究，本研究選定南臺灣一亞熱帶森林，評估森林地區相對反射強度值校正之可行性。規劃以單一航線，獲取六組掃描參數一致但航高不同之空載光達資料，航高從1403公尺至2745公尺，包含兩個飛行方向。
於測區內選定一均質之柏油路表面，藉由多重航高估算本研究區域之反射強度值校正參數。本研究發現飛機航向之改變會影響空載光達接收到之反射強度值，本研究稱此現象為「heading phenomenon」。根據本研究資料顯示，校正參數之估算會直接受到此現象影響，於處理資料時須謹慎注意。本研究之反射強度值校正考慮「heading phenomenon」、雷射能量隨距離傳播之衰減、大氣吸收散射之效應、因地形起伏導致之雷射入射角變化以及地表為非朗伯表面。
使用 ISODATA非監督式分類評估校正成果，雖然森林地區並未滿足光達方程式之假設，但據分類成果顯示，經完整反射強度值之校正後可消除資料間不同航高、航向之差異，達到有效區分地物之成果，其分類精度達到83.32%。

This study applied the relative intensity correction for the ALS data of a subtropical forestry area to evaluate the effectiveness of intensity correction in southern Taiwan. Our ALS data contains six flight strips with the altitudes varied from 1403 m to 2745 m, which were obtained with two different flying heading. A homogeneous road surface with asphalt pavement were used to estimate the parameters of the modified LiDAR equation.
This study found that the flying heading may affect the recorded intensity and the estimation of the parameters, and this phenomenon is called “heading phenomenon”. We consider the heading phenomenon, spherical loss, atmospheric effect, topographic effect and non-lambertian characteristic when conducting the intensity correction.
To evaluate the results of intensity correction in the forestry area, the ISODATA unsupervised classification was used. The classification of corrected intensity showed that although the forestry area did not fulfill the assumption of the LiDAR equation, which assumes the return signal is the ‘only return’, the results of the correction using first and only return are still acceptable. After all the intensity correction, the classification accuracy achieved a value of 83.32%.

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