WoS İndeksli Yayınlar Koleksiyonu
Permanent URI for this collectionhttps://hdl.handle.net/20.500.12416/8653
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Article Citation - WoS: 7Citation - Scopus: 9Rubinowicz Transform of the Mtpo Surface Integrals(Elsevier Science Bv, 2008) Umul, Yusuf Z.The surface integral of the modified theory of physical optics is reduced to a line integral by using the Rubinowicz transform for the incident scattered fields by an arbitrary aperture in a black surface. The integral theorem of Kirchhoff is applied to the scattering geometry and the diffracted fields are expressed in terms of a line integral along the contour of the diffracting edge. (C) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 1Citation - Scopus: 1Interaction of Electromagnetic Waves With a Resistive Half-Plane(Springer France, 2016) Umul, Yusuf Z.The interaction process of electromagnetic waves by a resistive half-plane is investigated. The scattered geometrical optics fields are obtained by subtracting the incident field from the total geometrical optics waves. The physical optics integral of the scattered waves is derived with the aid of the scattered geometrical optics fields. The edge diffracted waves are derived from the physical optics integral by the edge point technique. A correction field is added to the diffracted fields in order to obtain a solution that satisfies the resistive boundary conditions on the surface of the half-screen. The uniform diffracted fields are expressed in terms of the Fresnel function and the resultant field representations are compared with the literature numerically.Article Citation - WoS: 3Citation - Scopus: 4The Physical Optics Integral on the Scatterer's Unlit Surface(Elsevier Gmbh, 2014) Umul, Yusuf Z.The scattering integrals of the modified theory of physical optics are redefined according to the illuminated and unlit surfaces of the scattering object. With this aim the canonical problem of wedge diffraction is taken into account. It is shown that the new scattering integral contain two geometrical optics and diffracted fields. One of the geometrical optics waves is the reflected field component that propagates in the real space. The other one transmits to an imaginary space through the scattering surface and does not have any influence in the real space. The diffracted waves exist in the real space and satisfy the related boundary condition on the scattering surfaces. The resultant field expressions are compared with the exact series solution of the problem numerically. (C) 2014 Elsevier GmbH. All rights reserved.Article Citation - WoS: 5Citation - Scopus: 5Fringe Waves in Wedge Diffraction(Elsevier Gmbh, Urban & Fischer verlag, 2012) Umul, Yusuf Z.Explicit expressions for the non-uniform currents of the physical theory of diffraction are derived in terms of Fresnel functions for wedge diffraction by taking into account the surface integrals of the modified theory of physical optics. The obtained fringe waves are compared numerically by the asymptotic representations, found in the literature. (C) 2011 Elsevier GmbH. All rights reserved.Article Citation - WoS: 3Citation - Scopus: 4Diffraction of Plane Waves by a Black Wedge(Elsevier Sci Ltd, 2010) Umul, Yusuf Z.The scattering of plane waves by a black wedge is examined. Two methods are considered for the solution of the problem. A closed-form series solution is derived by performing the technique of the separation of variables using boundary conditions of Macdonald. The second approach is the method of the modified theory of physical optics. The results are compared numerically. (C) 2009 Elsevier Ltd. All rights reserved.Article Citation - WoS: 2Citation - Scopus: 3Wedge Diffraction in Terms of the Method of Physical Optics(Ieice-inst Electronics information Communications Eng, 2009) Umul, Yusuf Z.The method of physical optics is extended for wedge diffraction. The classical integral of physical optics is taken into account for the diffraction problem of plane waves by a conducting half-plane. The integral is decomposed according to the transmitted and reflected scattered waves. The sinusoidal term in the integrand is rewritten by considering the fact that the half-plane is a special case of the wedge. Two cases of soft and hard surfaces are examined and the uniform diffracted waves are obtained by the asymptotic evaluation of the integrals. The results are compared with the literature numerically.Article Citation - WoS: 12Citation - Scopus: 13The Relation Between the Boundary Diffraction Wave Theory and Physical Optics(Elsevier Science Bv, 2008) Umul, Yusuf Z.The physical optics surface integral is asymptotically reduced to a line integral along the contour of the diffracting edge. It is shown that the resultant integral can be separated into two sub-integrals which represent the reflected and transmitted diffracted fields. The integrands are transformed into the same forms with the potential function of the boundary diffraction wave theory. (C) 2008 Elsevier B.V. All rights reserved.Article Citation - WoS: 9Citation - Scopus: 9Uniform Version of the Modified Theory of Physical Optics Based Boundary Diffraction Wave Theory(Taylor & Francis Ltd, 2008) Umul, Yusuf Z.The potential function of the modified theory of physical optics based boundary diffraction wave theory is made uniform by using the principles of the uniform theory of diffraction. The line integration of this new function along the edge contour gives the uniform diffracted fields which are finite for the transition regions of the diffraction geometry. The method is applied to the diffraction problem by the edge of a curved surface.Article Citation - WoS: 33Citation - Scopus: 36Mtpo Based Potential Function of the Boundary Diffraction Wave Theory(Elsevier Sci Ltd, 2008) Umul, Yusuf Z.A novel potential function is introduced by using the modified theory of physical optics integrals for a perfectly conducting half-plane. The function is valid for arbitrary aspects of observation. The line integration of these functions gives the total scattered fields. The method is applied to the problem of diffraction of plane waves by an opaque half-plane for oblique incidence. (c) 2008 Elsevier Ltd. All rights reserved.Article Citation - WoS: 7Citation - Scopus: 8The Theory of the Boundary Diffraction Wave for Wedge Diffraction(Taylor & Francis Ltd, 2008) Umul, Yusuf Z.A new potential function, line integration which gives the edge diffracted fields, is constructed for wedge diffraction by using the method of modified theory of physical optics. The surface integrals are transformed into line integrals by the technique of asymptotic reduction. As an application of the novel potential function, the diffracted field is obtained for the geometry of a wedge for arbitrary incidence of plane waves.