Search for dissertations about: "magnetometer"

Showing result 1 - 5 of 37 swedish dissertations containing the word magnetometer.

2. 1. High-temperature superconducting magnetometers for on-scalp MEG

   Author : Silvia Ruffieux; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES; on-scalp MEG; multi-channel system; SQUID optimization; kinetic inductance magnetometer; magnetoencephalography; magnetometer; crosstalk; SQUID magnetometer calibration; high-Tc SQUID; kinetic inductance;

   Abstract : In the growing field of on-scalp magnetoencephalography (MEG), brain activity is studied by non-invasively mapping the magnetic fields generated by neuronal currents with sensors that are flexibly placed in close proximity to the subject's head. This thesis focuses on high-temperature superconducting magnetometers made from YBa2Cu3Ox-7 (YBCO), which enables a reduction in the sensor-to-room temperature standoff distance from roughly 2 cm (for conventional MEG systems) down to 1 mm. READ MORE

4. 2. Magnetoresistance and Space : Micro- and Nanofeature Sensors Designed, Manufactured and Evaluated for Space Magnetic Field Investigations

   Author : Anders Persson; Hugo Nguyen; Greger Thornell; Johan Åkerman; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Tunneling Magnetoresistance; Planar Hall effect; Magnetic tunnel junction; Magnetometer; Materials science; Teknisk materialvetenskap; Engineering physics; Teknisk fysik; Teknisk fysik med inriktning mot mikrosystemteknik; Engineering Science with specialization in Microsystems Technology;

   Abstract : In recent years, the interest for miniaturization of spaceborne instruments and subsystems has increased steadily, as this enables development of small and lightweight satellite classes as well as more versatile payloads on traditional spacecraft. In essence, this thesis work is an investigation of the applicability of magnetoresistive technology to a magnetometer intended for space. READ MORE

5. 3. Filtering extracting features from infrasound data

   Author : José Chilo; Thomas Lindblad; Christian Bohm; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; infrasound; seismic signals; feature extraction; wavelets; fingerprints; mining; magnetometer; Physics; Fysik; Electronics;

   Abstract : The goal of the research presented in this thesis is to extract features, to filter and get fingerprints from signals detected by infrasound, seismic and magnetic sensors. If this can be achieved in a real time system, then signals from various events can be detected and identified in an otherwise torrent data. READ MORE

6. 4. On-scalp MEG using high-Tc SQUIDs: Measuring brain activity with superconducting magnetometers

   Author : Christoph Pfeiffer; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; high-Tc SQUID; neuroimaging; magnetoencephalography; localization; on-scalp MEG; sensor array; magnetometer;

   Abstract : This thesis describes work done towards realizing on-scalp magnetoencephalography (MEG) based on high critical temperature (high- T c) superconducting quantum interference device (SQUID) sensors. MEG is a non-invasive neuroimaging modality that records the magnetic fields produced by neural currents with good spatial and high temporal resolution. READ MORE

7. 5. Fabrication and Characterization of magnetometer for space applications

   Author : Fatjon Qejvanaj; Johan Åkerman; BRAD ENGEL; KTH; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; AMR; Magnetic sensor; Ferromagnetic; Antiferromagnetic; NiFe; IrMn; exchange bias.; Fysik; Physics; Teknisk materialvetenskap; Materials Science and Engineering;

   Abstract : The present rapid increase in the number of space missions demands a decrease in the cost of satellite equipment, but also requires the development of instruments that have low power consumption, low weight, and small size.Anisotropic magnetoresistance (AMR) sensors can answer these needs on account of their small size, weight, and power consumption. READ MORE