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Register a new userComparative Study Of Several Mathematical Methods for building Continuous surface Based On 3D Laser Scanning Clouds
دراسة مقارنة لعدة طرائق استقراء رياضية لسطح مستمر اعتماداً على غمامات المسح الليزري ثلاثي الأبعاد
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Damascus University ورقة بحثية
Publication date
2012
fields
Civil Engineering
and research's language is
العربية
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Shamra Editor
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يركز البحث على دراسة مقارنة بين مجموعة من طرائق استقراء رياضية تطبق على حزمة كبيرة و كثيفة من النقاط لمنطقة ممسوحة بتقنية الليزر الجوي ذات الدقة العالية، بحيث تعبر عن تمثيل سطح الأرض الطبيعية الرقمي فقط. اعتمد لتطبيق ذلك مجموعة متنوعة من المناطق التي مسحت ليزرياً و التي تعبر عن حالات متنوعة من حيث تعقيد التضاريس، مع الأخذ بالحسبان إهمال الأجسام الصنعية و أخذ كثافات متنوعة من الغمامات الليزرية لجعل الدراسة أكثر شمولاً. طبقت بعد ذلك مجموعة من خوارزميات الاستقراء الرياضي للسطوح على المناطق السابقة بهدف تحديد طريقة الاستقراء الأمثل، و من ثم قورنت نتائج الاستقراء التي أعطتها الطرائق جميعها، و قد أظهرت النتائج تأثير كثافة البيانات المستخدمة في اختيار نوع طريقة الاستقراء الرياضية المثلى و أن تابع الاستقراء باستخدام خوارزمية المجاور الأقرب ( Nearest Neighbor ) لنقاط الليزر الجوي الكثيف يعطي نتائج جيدة جداً مقارنة ببقية الطرائق.
In this paper, comparisons between several mathematical interpolation methods applied on high accuracy and huge laser clouds which only represents the DTM. In order to implicate the aforementioned, a group of a variety of Laser Scanned Areas has been chosen to represent different types of terrain including complex and flat terrain, taking into account that man-made features are not involved in this study and that different Laser Clouds density is used to make the study more general. A different set of algorithms were applied to conclude which one is more suitable. This step was followed by the comparison between different interpolation results. The results have shown that the Points' Density has a great impact on a manner in which the optimal interpolation method is applied. Moreover, it has proven that the Nearest Neighbor Algorithm is the best applied method compared with the other alternatives
References used
American Society for Photogrammetry and Remote Sensing (ASPRS). 2007. “ASPRS Guidelines: Vertical Accuracy Reporting for Lidar Data.” American Society for Photogrammetry and Remote Sensing. Accessed http:// www.asprs.org
A. Carrara, G. Bitelli and R. Carla, 1997. Comparison of techniques for generating digital terrain models from contour lines, in International Journal of Geographical Information Science 11(5), pp. 451-473
Christopher D. Lloyd, 2010. Local Models for Spatial Analysis, second edition, pages 150-168, http://books.google.com/books
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