Admasu Abebe* Zelalem Tesfaye** Abstract Historically, in different countries walls are built for different purposes. Among others, defense purpose is the most common one. For instance, to mention a few, we do have the Great Wall of China was built from 3rdcentury B.C to 17thcentury A.D, the Great Zimbabwe Wall was built from 1100–1450 A.D; […]

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