Yazar "Işık University, Faculty of Arts and Sciences, Department of Mathematics" için FEF - Bildiri Koleksiyonu | Matematik Bölümü / Department of Mathematics listeleme
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Beam tracing theory in Minkowski space
Hasanoğlu, Elman (IEEE, 2011)This paper provides a novel approach to beam theory in homogeneous lossless mediun. The main idea is to interpret the classic eikonal equation in three dimensional Minkowski space. -
Bounded harmonic mappings related to starlike functions
Varol, Dürdane; Aydoğan, Seher Melike; Polatoğlu, Yaşar (Amer Inst Physics, 2014-12-17)Let f = h(z) + <(g(z))over bar> be a sense-preserving harmonic mapping in the open unit disc D = {z vertical bar vertical bar z vertical bar < 1}. If f satisfies the condition vertical bar 1/b(1) g'(z)/h' (z) - M vertical ... -
Complex and real rays in three dimensional Minkowski space
Hasanoğlu, Elman (IEEE, 2002)A new approach to the theory of complex rays is proposed. It is shown that the Minkowski space is more appropriate for describing these rays than the usual, Euclidian spaces. Some illustrative examples are represented. -
Cross-sectional thermoacoustic imaging using multi-layer cylindrical media
Elmas, Demet; Ünalmış Uzun, Banu; İdemen, Mehmet Mithat; Karaman, Mustafa (IEEE, 2017-11-10)For cross-sectional two-dimensional thermoacustic imaging of breast and brain, we explored solution of the wave equation using layered tissue model consisting of concentric annular layers on a cylindrical cross-section. ... -
Çok katmanlı düzlemsel ortam için termoakustik dalga denkleminin çözümü
Bayıntır, Hazel; Ünalmış Uzun, Banu; İdemen, Mehmet Mithat; Karaman, Mustafa (IEEE, 2017-06-27)Bu çalışmada, farklı akustik parametrelere sahip çok katmanlı düzlemsel ortam için tüm katmanlarda kaynak dağılımı olduğu varsayımı altında termoakustik dalga denkleminin analitik olarak düz ve ters çözümü elde edilmiştir. ... -
Çok katmanlı silindirik yapılar için termoakustik dalga denkleminin ters çözümü
Elmas, Demet; Ünalmış Uzun, Banu; İdemen, Mehmet Mithat; Karaman, Mustafa (IEEE, 2017-06-27)Termoakustik görüntüleme, elektromanyetik enerji uyarımı ile ultrason dalgaları oluşumunu sağlayan yeni bir yöntemdir. Bu sistemin görüntüleme işlemi termoakustik dalga denkleminin ters çözümüne dayanmaktadır. Ters çözümde ... -
A function of direction in a Weyl subspace associated with a set of orthogonal vector fields
Özdeğer, Abdülkadir (World Scientific Publ Co Pte Ltd, 2003)Let W-m be an m-dimensional subspace of an n-dimensional Weyl space W-n. Suppose that (1)v, (2)v,..., (m)v are mutually orthogonal smooth vector fields in W-m and that v is a non-tangential smooth vector field defined on ... -
“International conference on vibration problems” ICOVP-2007 and a short history
İnan, Esin (Springer Science and Business Media, LLC, 2008)[No abstract available] -
A method for calculating profiles of a dielectric thick lenses
Hasanoğlu, Elman (IEEE, 2001)Hasanov and Polat (see International Journal of Electronics and Communications (AEO), vol.54, no.2, p.109-113, 2000) investigated the transformation of a plane wavefront to another plane wavefront after passing through a ... -
Nonlinear wave modulation in a prestressed thin elastic tube filled with an inviscid fluid
Bakırtaş, İlkay; Demiray, Hilmi (Wit Press, 2002)In the present work, employing the nonlinear equations of an incompressible, isotropic and elastic thin tube and the approximate equations of an incompressible inviscid fluid and then utilizing the reductive perturbation ... -
Nonlinear waves in a stenosed elastic tube filled with viscous fluid: Forced perturbed korteweg-de vries equation
Tay, Kim Gaik; Demiray, Hilmi; Tiong, Ong Chee (Springer Science and Business Media, LLC, 2008)In the present work, treating the artery as a prestressed thin-walled and long circularly cylindrical elastic tube with a mild symmetrical stenosis and the blood as an incompressible Newtonian fluid, we have studied the ... -
Nonlinear waves in fluid-filled elastic tubes: A model to large arteries
Demiray, Hilmi (Springer, 2007)In the present work, by treating the arteries as a prestressed thin walled elastic tube of variable radius and the blood as an incompressible inviscid fluid, we have studied the propagation of weakly nonlinear waves in ... -
On complex solutions of the eikonal equation
Hasanoğlu, Elman (IEEE, 2007)In this paper a new approach of complex rays in an inhomogeneous medium is presented. Complex rays are complex solutions of the eikonal equation, the main equation of the geometical optics. It is shown that solving the ... -
On pseudo-umbilical rotational surfaces with pointwise 1-type gauss map in E-2(4)
Bektaş, Burcu; Canfes, Elif Özkara; Dursun, Uğur (Istanbul Technical Univ, 2017-01-01)In this work, we study two families of rotational surfaces in the pseudo Euclidean space 1E4 with profile curves lying in 2 dimensional planes. First, we obtain a classification of pseudo umbilical spacelike surfaces and ... -
Quasiconformal harmonic mappings related to Janowski alpha-spirallike functions
Aydoğan, Seher Melike; Polatoğlu, Yaşar (Amer Inst Physics, 2014)Let f = h(z) + g(z) be a univalent sense-preserving harmonic mapping of the open unit disc D = {z/vertical bar z vertical bar < 1}. If f satisfies the condition vertical bar omega(z)vertical bar = vertical bar g'(z)/h'(z)vertical ... -
Thermoacoustic image reconstruction based on layered tissue model
Bayıntır, Hazel; İdemen, Mehmet Mithat; Ünalmış Uzun, Banu; Karaman, Mustafa; Elmas, Demet (SPIE-Int Soc Optical Engineering, 2017)We derived analytical forward and inverse solution of thermoacoustic wave equation for inhomogeneous multi layered planar and cylindrical mediums with the source distribution existing in all layers. These solutions are ... -
Travelling waves in a prestressed elastic tube filled with a fluid of variable viscosity
Demiray, Hilmi; Gaik, Tay Kim (Springer, 2008)In this work, treating the artery as a prestressed thin elastic tube with variable radius and the blood as all incompressible Newtonian fluid with variable viscosity, the propagation of nonlinear waves ill Such a composite ... -
Two reflector non symmetric shaped antenna systems
Hasanoğlu, Elman (IEEE, 2000)Two reflector antenna systems with non symmetric reflecting surfaces under GO approximation are investigated. It is shown, that the problem of forming desired far field pattern leades to solving the system of partial ... -
Variable coefficient Korteweg-deVries equation in fluid-filled elastic tubes
Demiray, Hilmi (Technical University Liberec, 2011-09-05)In the present work, treating the arteries as a prestressed thin elastic tube with a stenosis and the blood as an inviscid fluid, we have studied the propagation of weakly nonlinear waves in such a medium by use of the ...