Java applets for simulation of magnetic resonance imaging

Altın, Çağdaş
The aim of this study is to develop an easily accessible and realistic magnetic resonance imaging (MRI) simulation tool for educational and research purposes. With this aim, NMR (nuclear magnetic resonance imaging) phenomenon is simulated based on the physical principles, starting from the motion of a spin under the influence of external magnetic fields to pulse sequences generating the image. The inputs of the simulation are a 3D virtual object and a pulse sequence definition. The simulation software generates slice images using Fourier reconstruction method. To perform a more realistic simulation, the Bloch equation, which explains the behavior of a spin under external magnetic fields, is solved by using numerical methods. This enables to observe the behavior of a spin system under any magnetic field influence, not only for resonance condition. The simulation successfully simulates T2* affect by using inhomogeneous static magnetic field distribution over the entire volume of the object. The software is implemented in Java language and developed as a Java applet. A support tool is developed which allows observing NMR phenomenon. The simulation can produce realistic images, generate many of the artifacts in MRI, like intra-voxel dephasing, chemical shift, cross-talk (since it simulates the whole process), and has the advantage of being web-based compared to the existing stand-alone MRI simulations.


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İnce, Kutalmış Gökalp; Alatan, Abdullah Aydın; Department of Electrical and Electronics Engineering (2009)
In this thesis, a visual 3-D eye gaze tracker is designed and implemented to tested via computer simulations and on an experimental setup. Proposed tracker is designed to examine human perception on autostereoscopic displays when the viewer is 3m away from such displays. Two different methods are proposed for calibrating personal parameters and gaze estimation, namely line of gaze (LoG) and line of sight (LoS) solutions. 2-D and 3-D estimation performances of the proposed system are observed both using comp...
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Özsüt, Murat Eşref; Eyüboğlu, Behçet Murat; Department of Electrical and Electronics Engineering (2005)
Data acquisition and image reconstruction tasks of METU Magnetic Resonance Imaging (MRI) System are used to be performed by a 15 year-old technology. This system is incapable of transmitting control signals simultaneously and has memory limitations. Control software is written mostly in assembly language, which is hard to modify, with very limited user interface functionality, and time consuming. In order to improve the system, a LabVIEW based data acquisition system consisting of a NI-6713 D/A card (to gen...
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Baştanlar, Yalın; Çetin, Yasemin; Department of Information Systems (2005)
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Application of sar techniques in an ultrasound testbed
Solak, Güven; Tuncer, Temel Engin; Department of Electrical and Electronics Engineering (2008)
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Capacitive cmos readout circuits for high performance mems accelerometers
Kepenek, Reha; Külah, Haluk; Department of Electrical and Electronics Engineering (2008)
This thesis presents the development of high resolution, wide dynamic range sigma-delta type readout circuits for capacitive MEMS accelerometers. Designed readout circuit employs fully differential closed loop structure with digital output, achieving high oversampling ratio and high resolution. The simulations of the readout circuit together with the accelerometer sensor are performed using the models constructed in Cadence and Matlab Simulink environments. The simulations verified the stability and proper ...
Citation Formats
Ç. Altın, “Java applets for simulation of magnetic resonance imaging,” M.S. - Master of Science, Middle East Technical University, 2008.