Fen Bilimleri Enstitüsü: Recent submissions

  • Creating multi-touch haptic feedback on an electrostatic tactile display 
    Sarkandi, Gholamreza Ilkhani. (TThesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2017., 2017.)
    This study is composed of two main parts. In the first part, we present single touch electrostatic tactile display analysis and modelling together with some prelim inary observation on conventional rendering methods. ...
  • Computational and experimental investigation of low frequency noise in passenger vehicles 
    Oktav, Akın. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2016., 2016.)
    In this study, low frequency noise characteristics of passenger vehicles are addressed. Vehicle noise variability and dominant paths that cause low frequency booms are investigated. To diagnose the cause of variability, a ...
  • Design and analysis of three-dimensional phononic band gap structures with embedded intertial amplification mechanisms 
    Tanıker, Semih. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2015., 2015.)
    In this study, three-dimensional (3D) phononic band gap structures are investigated. First, in nite and nite periodic simple cubic, body centered cubic and face centered cubic lattices with and without inertial ampli ...
  • Convergence acceleration procedures for the computation of 2-D transonic flows 
    Türk, Uğur (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2014., 2014.)
    This study addresses a novel adaptive time stepping procedure, which leads to selection of larger time steps allowed by the physics of the problem. Information about the gradients of the flow variables can be regarded as ...
  • Production of antibacterial hydroxyapatite 
    İpekoğlu, Mehmet. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2011., 2011.)
    Hydroxyapatite was produced by rapid microwave synthesis method. Effects of microwave power and duration were examined on the powder morphology of the hydroxyapatite powder during the synthesis process and microwave aging ...
  • Numerical investigation of isothermal and non-isothermal viscoelastic flow in lid-driven polar cavity 
    Mercan, Hatice. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2012., 2012.)
    The isothermal and non-isothermal viscoelastic ow of Phan-Thien-Tanner (PTT) uids is considered in lid-driven polar cavity geometry, with stationary and oscillatory lid motion, using a numerical solution method with ...
  • Theoretical and numerical analysis of fracture of shape memory alloys 
    Hazar, İbrahim Selçuk. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2014., 2014.)
    The subject of this thesis is theoretical and numerical analysis of the fracture of SMAs. First, the size of the martensitic region surrounding the tip of an edge-crack in a SMA plate is calculated analytically using the ...
  • Shape optimization of thin-walled tubes under high-velocity axial and transverse impact loadings 
    Tanlak, Niyazi. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2014., 2014.)
    Thin-walled tubes are one of the most commonly used parts in structural ap- plications. More specifically, they are used as passive safety measures in vehicles like bumper-beams and crash-boxes. They take loads either ...
  • Multi-objective robust control of rotor / active magnetic bearing systems 
    Kuseyri, İbrahim Sina. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2011., 2011.)
    This dissertation considers the application of recent robust linear control techniques to rotors with active magnetic bearings. Rotors suspended with electromagnetic bearings are inherently unstable; therefore feedback ...
  • Fabrication and characterization of Al, AlMgSi, and AlSi foams 
    Mahmutyazıcıoğlu, Nazım. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2010., 2010.)
    Manufacturing of metal foams by using powder compact melting (PCM) method, with the most important considerations like material and method selection, powder blending, cold compaction, hot compaction and hot extrusion and ...
  • Failure criteria for functionally graded materials and application of GTN model using finite elements 
    Oral, Alpay. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2010., 2010.)
    Functionally Graded Materials (FGMs) are special composites with a point to point continuous property variation. In this failure of laboratory scale FGMs is modeled using Gurson - Tvergaard -Needleman (GTN) model. Stress, ...
  • Design optimization of structures under fatigue loading 
    Ertaş, Ahmet Hanifi. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2009., 2009.)
    Many of the engineering failures are caused by fatigue. Fatigue failure can be defined as the tendency of a material to fracture by means of progressive brittle cracking under cyclic stresses. Because mechanical components ...
  • A framework for the analysis of coupled-physics models using adaptive multi-level techniques 
    Turan, Erhan. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2010., 2010.)
    This object of this study is to develop a computational framework to analyze coupled-physics problems within the context of multi-level methods. Adaptive solution strategies in conjunction with Newton-Krylov and Domain ...
  • Gain-scheduled air path system control and compressor air mass flow estimation in diesel engines 
    Atam, Ercan. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2010., 2010.)
    In this dissertation, we deal with the independent problems of air path system control and compressor air mass flow estimation in diesel engines. In this regard, the thesis can be divided into two main parts: control and ...
  • Three-dimensional solution of compressible potential flow in turbomachinery by a finite element method 
    Güneş, Doğan. (Thesis (Ph.D.) - Bogazici University. Institute for Graduate Studies in Science and Engineering, 1983., 1983.)
    The present study is concerned with the analysis of three-dimensional, compressible flows in axial-, radial-, or mixed-flow turbomachinery under the limitations of steady and potential flow conditions. The basic approach ...
  • Numerical analysis of surface-driven non-isothermal viscoelastic flow 
    Kaptan, Yalın. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2010., 2010.)
    The numerical investigations of the moving edge non-isothermal viscoelastic flows are simulated by using two example problems (lid driven cavity (LDC) and rotating disc in a cylindrical enclosure (RDCE) flows) in this ...
  • Design of composite structures for minumum weight 
    Akbulut, Mustafa. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2010., 2010.)
    The goal of this study is to develop methodologies to optimize the structural design of composite materials to achieve the minimum weight. Mainly three different problem areas were considered. Firstly, weight minimization ...
  • Closed-loop actuator and sensor location selection strategies for flexible structures 
    Güney, Murat. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2008., 2008.)
    In this thesis, the problem of finding the optimal actuator and sensor locations for vibration control of a flexible structure is studied. An iterative search strategy is used, where the closedloop criteria are selected ...
  • Finite element analysis of plasticity-induced fatigue crack closure 
    Gökçen, Mehmet Gökhan. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2008., 2008.)
    Contact elements are implemented into the elastic-plastic finite element analysis of fatigue crack closure to predict crack opening stress, by developing a code using ANSYS Parametric Design Language. Although the use of ...
  • Optimum vibration absorbers for continuous and discrete mechanical systems 
    Tursun, Murat. (Thesis (Ph.D.)-Bogazici University. Institute for Graduate Studies in Science and Engineering, 2008., 2008.)
    In this thesis, the optimum parameters of passive vibration absorbers for continuous and discrete mechanical systems are investigated. Two approaches are undertaken to obtain the optimum absorber parameters. The first ...