<p><!-- /* Font Definitions */ @font-face {font-family:SimSun; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:宋体; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} @font-face {font-family:"\@SimSun"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:SimSun; mso-fareast-language:ZH-CN;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 70.85pt 70.85pt 70.85pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --><p>Magnetiskresonanstomografi, MRI, är en användbar teknik inom flera områden, i denna uppsats ligger fokus på användning inom medicin. Fysiken som ligger bakom MRI presenteras, som t ex uppdelning av energinivåer och kärnmagnetiskresonans. Uppbyggnad och tekniken som ligger bakom MRI har även studeras. Sedan har det gjorts jämförelse mellan MRI, röntgen och datortomografi.</p><p> </p><p>Utöver litteraturstudierna har simulering gjorts. I denna del har en modell för hjärnan byggts i programmet Comsol Multiphysics. I denna modell har studier av energiöverföringen, magnetiska fältet och elektriska fältet gjorts. Modellen har lösts både som stationärt problem och som tidsberoende. För energiöverföringen som redovisas som tidsmedelvärdet ser resultaten liknade ut för det stationära fallet som för de tidsberoende fallen, dock om man inte ser på tidsmedelvärdet utan energiöverföring under hela tiden så kan man dra slutsatsen att det stationära fallet är det mest kritiska.</p></p> / <p><!-- /* Font Definitions */ @font-face {font-family:SimSun; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:宋体; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} @font-face {font-family:"\@SimSun"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:SimSun; mso-fareast-language:ZH-CN;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 70.85pt 70.85pt 70.85pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} --><p>Magnetic resonance imaging, MRI, is a useful technical method in many different areas; in this report lies focus on uses in medicine. MRI has been studied from a physical meaning, such as nuclear magnetic resonance, NMR, and spin splitting. A technical perspective of MRI has been studied, such as how MRI is built-up and technical details. MRI has been compared with Computed Tomography, CT, and X-rays.</p><p> </p>In addition to the theoretical studies, have simulations using the programme Comsol Multiphysics been done. One model has been built up to simulate MRI influences on the brain. The energy transfer, magnetic field and electric field have been studied. The model has been solved both as stationary and as time dependent problem. In the solution can a small difference be noticed which depend on that the results show the time average. If one studies the real solution, not the time average, can one conclusion rather quickly been drawn that the stationary solution have the highest transferred energy.</p>

<!-- /* Font Definitions */ @font-face {font-family:SimSun; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:宋体; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} @font-face {font-family:"\@SimSun"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:SimSun; mso-fareast-language:ZH-CN;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 70.85pt 70.85pt 70.85pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} -->Magnetiskresonanstomografi, MRI, är en användbar teknik inom flera områden, i denna uppsats ligger fokus på användning inom medicin. Fysiken som ligger bakom MRI presenteras, som t ex uppdelning av energinivåer och kärnmagnetiskresonans. Uppbyggnad och tekniken som ligger bakom MRI har även studeras. Sedan har det gjorts jämförelse mellan MRI, röntgen och datortomografi.   Utöver litteraturstudierna har simulering gjorts. I denna del har en modell för hjärnan byggts i programmet Comsol Multiphysics. I denna modell har studier av energiöverföringen, magnetiska fältet och elektriska fältet gjorts. Modellen har lösts både som stationärt problem och som tidsberoende. För energiöverföringen som redovisas som tidsmedelvärdet ser resultaten liknade ut för det stationära fallet som för de tidsberoende fallen, dock om man inte ser på tidsmedelvärdet utan energiöverföring under hela tiden så kan man dra slutsatsen att det stationära fallet är det mest kritiska. / <!-- /* Font Definitions */ @font-face {font-family:SimSun; panose-1:2 1 6 0 3 1 1 1 1 1; mso-font-alt:宋体; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} @font-face {font-family:"\@SimSun"; panose-1:0 0 0 0 0 0 0 0 0 0; mso-font-charset:134; mso-generic-font-family:auto; mso-font-format:other; mso-font-pitch:variable; mso-font-signature:1 135135232 16 0 262144 0;} /* Style Definitions */ p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-parent:""; margin:0cm; margin-bottom:.0001pt; mso-pagination:widow-orphan; font-size:12.0pt; font-family:"Times New Roman"; mso-fareast-font-family:SimSun; mso-fareast-language:ZH-CN;} @page Section1 {size:612.0pt 792.0pt; margin:70.85pt 70.85pt 70.85pt 70.85pt; mso-header-margin:36.0pt; mso-footer-margin:36.0pt; mso-paper-source:0;} div.Section1 {page:Section1;} -->Magnetic resonance imaging, MRI, is a useful technical method in many different areas; in this report lies focus on uses in medicine. MRI has been studied from a physical meaning, such as nuclear magnetic resonance, NMR, and spin splitting. A technical perspective of MRI has been studied, such as how MRI is built-up and technical details. MRI has been compared with Computed Tomography, CT, and X-rays.   In addition to the theoretical studies, have simulations using the programme Comsol Multiphysics been done. One model has been built up to simulate MRI influences on the brain. The energy transfer, magnetic field and electric field have been studied. The model has been solved both as stationary and as time dependent problem. In the solution can a small difference be noticed which depend on that the results show the time average. If one studies the real solution, not the time average, can one conclusion rather quickly been drawn that the stationary solution have the highest transferred energy.