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تسجيل مستخدم جديدتقارب التقدير الذراعي المنفصل. II. تقنية استخدام التحسين لزيادة الدقة
Convergence of the discrete dipole approximation. II. An extrapolation technique to increase the accuracy
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نقترح تقنية اكسترابوليشن تسمح بتحسين دقة الحسابات التقريب الثنائي المقطع. تم دراسة أداء هذه التقنية على أساس تجارب كبيرة لخمسة حالات اختبار باستخدام العديد من التقطيعات المختلفة. كانت جودة الاكسترابوليشن يتحسن مع التقطيع المحسن بشكل كبير خاصة للجسيمات المشكلة بشكل كوبي. تم إثبات تخفيض فائدة مرتفعة من الخطأ. كما نقترح تقديرات لخطأ الاكسترابوليشن الذي تم إثباته أنه موثوق به. وأخيرا نقترح طريقة بسيطة لفصل خطأ الشكل والتقطيع وذلك باستخدام حالة اختبار واحدة.
We propose an extrapolation technique that allows accuracy improvement of the discrete dipole approximation computations. The performance of this technique was studied empirically based on extensive simulations for 5 test cases using many different discretizations. The quality of the extrapolation improves with refining discretization reaching extraordinary performance especially for cubically shaped particles. A two order of magnitude decrease of error was demonstrated. We also propose estimates of the extrapolation error, which were proven to be reliable. Finally we propose a simple method to directly separate shape and discretization errors and illustrated this for one test case.
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