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Yayın Afforestation of arid and semiarid ecosystems in Turkey(Tubitak Scientific & Technical Research Council Turkey, 2017-05-28) Çalışkan, Servet; Boydak, MelihSustainable management of arid and semiarid forests requires careful planning and implementation. Afforestation by planting and seeding is a fundamental tool for the establishment of new forests on barren landscapes and restoration of degraded forests in arid and semiarid ecosystems. In afforestation efforts, the consideration of site preparation, selection of species, seed source, and planting methods pose a number of ecological and economic challenges. Possessing one of the world's richest floras, Turkey suffered from heavy degradation during the last millennia. Some studies suggested that forests and steppes once covered 60%-70% and 10%-15% of the Anatolian landscape, respectively. Growing population, overgrazing, clearance for agriculture, fires, excessive timber harvesting, and misuse of lands led to a 26% reduction in the forest area. The Turkish Forest Service completed 2.3 million ha of afforestation and 1.2 ha of erosion control works, mostly in semiarid landscapes. This article presents an assessment of afforestation activities in the semiarid and arid regions of Turkey and is a review of the efforts exerted during the period 1945 to 2014.Yayın An Inverse recursive algorithm to retrieve the shape of the inaccessible dielectric objects(Ramazan YAMAN, 2024-10-16) Sefer, AhmetA regularized electromagnetic iterative inverse algorithm is formulated and im-plemented to reconstruct the shape of 2D dielectric objects using the far-fieldpattern of the scattered field data. To achieve this, an integral operator thatmaps the unknown boundary of the object onto the far-field pattern of thescattered field is defined and solved for the unknown boundary. The addressedinverse problem has an ill-posed nature and inherits nonlinearity. To over-come these, the proposed solution is linearized via Newton and regularized byTikhonov in the sense of least squares. Besides, the dominance of the shadowregion in the inverse-imaging process is exceeded by considering the superpo-sition of multi-incoming plane waves, leading to less computational cost and avery fast inversion process. Comprehensive numerical analyses are carried outto ascertain the algorithm’s feasibility, revealing that it is very efficient andpromising.
