Journals / Communications Faculty of Sciences University of Ankara Series A1 Mathematics and Statistics / 2026 / Volume: 69 Issue: 1

W--line congruences

Rashad Abdel-baky(King Abdulaziz University)0000-0001-7016-9280
Ferhat Taş(İSTANBUL ÜNİVERSİTESİ)0000-0001-5903-2881
Pages
—
Publication Date
2020-06-30
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AI Summary & Key Takeaways

AI Insight
⚡ TL;DR(Too Long; Didn't Read)

As a result, the middle focal surface of the normal line congruence is presented as a new surface interrogation tool.

📌 3 Key Takeaways

🎯
Objective & Hypothesis:By utilizing the Darboux frames, along with a regular surface whose parametric curves are lines of curvature, we analyzed the normal line congruence which preserves the asymptotic curves between its focal surfaces.
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Key Findings & Data:Moreover, a necessary and sufficient condition that the focal surfaces of the normal line congruence are degenerates into curves is derived.
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Conclusion & Impact:As a result, the middle focal surface of the normal line congruence is presented as a new surface interrogation tool.
🔬Design:Research Article
📍Scope:Comprehensive Sample
⚙️Variables:Lines of curvature · W-Line congruence · Area preserving representation

Abstract

By utilizing the Darboux frames, along with a regular surface whose parametric curves are lines of curvature, we analyzed the normal line congruence which preserves the asymptotic curves between its focal surfaces. This allows deriving systems of partial differential equations through which the problem of determining the director surface and the corresponding normal line congruence could be solved. Moreover, a necessary and sufficient condition that the focal surfaces of the normal line congruence are degenerates into curves is derived. As a result, the middle focal surface of the normal line congruence is presented as a new surface interrogation tool.

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Cite This Article

Abdel-baky, R., Taş, F. (2020). W--line congruences. Communications Faculty of Sciences University of Ankara Series A1 Mathematics and Statistics, Volume: 69 Issue: 1. https://doi.org/10.31801/cfsuasmas.550369

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