Sökning: "phantom"

Visar resultat 36 - 40 av 171 avhandlingar innehållade ordet phantom.

  1. 36. Studies on the use of digital radiography for the assessment of periapical bone lesions

    Författare :Boel Kullendorff; Helsingborg Kliniska Vetenskaper; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; subtraction radiography; image processing; Digital radiography; dental radiography; Odontology; stomatology; Odontologi;

    Sammanfattning : The aim was to study digital radiography and to evaluate the influence of image processing on digital dental radiographs for the assessment of periapical lesions. In four studies, artificial bone lesions were made periapically and interradicularly in the mandibular premolar and molar regions. LÄS MER

  3. 37. Maximum likelihood estimation in signal analysis of MR spectroscopy

    Författare :Pia Löthgren; Sveriges lantbruksuniversitet; Sveriges lantbruksuniversitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; NATURVETENSKAP; NATURAL SCIENCES;

    Sammanfattning : Proton magnetic resonance spectroscopy (MRS) is used to determine the concentration of metabolites in organic tissues, or to study metabolic changes in a non-invasive way. The complex-valued magnetic resonance spectroscopy signals are assumed to be disturbed by additive white noise. LÄS MER

  4. 38. Contrast-Enhanced Magnetic Resonance Angiography - Development and optimization of techniques for paramagnetic and hyperpolarized contrast media

    Författare :Jonas Svensson; Malmö Medicinsk strålningsfysik; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; egenskaper elektriska; Kondenserade materiens egenskaper:elektronstruktur; spectroscopy; relaxation; Angiography; Magnetic resonance; Contrast-enhanced; Hyperpolarized; Condensed matter:electronic structure; 13C; supraconductors; electrical; magnetic and optical properties; magnetiska och optiska ; supraledare; magnetisk resonans; spektroskopi;

    Sammanfattning : Contrast-enhanced magnetic resonance angiography (CE-MRA) is a diagnostic method for imaging of vascular structures based on nuclear magnetic resonance. Vascular enhancement is achieved by injection of a contrast medium (CM). LÄS MER

  5. 39. Attenuation correction in pulmonary and myocardial single photon emission computed tomography

    Författare :Helén Almquist; Lund Klinisk fysiologi; []
    Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Klinisk fysiologi; tomography; medical instrumentation; radiology; Clinical physics; downscatter; myocardial perfustion; ventilation-perfusion ratio; radiologi; pulmonary density; pulmonary perfusion; attenuation correction; SPECT; transmission measurement; tomografi; medicinsk instrumentering;

    Sammanfattning : The objective was to develop and validate methods for single photon emission computed tomography, SPECT, allowing quantitative physiological and diagnostic studies of lung and heart. A method for correction of variable attenuation in SPECT, based on transmission measurements before administration of an isotope to the subject, was developed and evaluated. LÄS MER

  7. 40. Antennas, Wave Propagation, and Localization in Wireless Body Area Networks

    Författare :Rohit Chandra; Institutionen för elektro- och informationsteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Wireless Body Area Network; WBAN; body sensor network; body-centric communication; wearable devices; ear-to-ear propagation; antennas; analytical propagation model; localization; wireless capsule endoscopy; in-mouth device; implants;

    Sammanfattning : A network of communicating wireless devices that are implantable, wearable or within close proximity of a human body is called wireless body area network (WBAN). The propagation channels for the devices in the WBAN are either through the body or over the body. LÄS MER