Sökning: "helical axis"

Visar resultat 1 - 5 av 17 avhandlingar innehållade orden helical axis.

1. 1. Biomechanical assessment of head and neck movements in neck pain using 3D movement analysis

   Författare :Helena Grip; Gertjan Ettema; Umeå universitet; []
   Nyckelord :movement analysis; kinematics; helical axis; neck pain; whiplash; cervical spine; pattern classification; motor control; head-eye co-ordination; head movement; biomedicinsk strålningsvetenskap; Biomedical Radiation Science;

   Sammanfattning : Three-dimensional movement analysis was used to evaluate head and neck movement in patients with neck pain and matched controls. The aims were to further develop biomechanical models of head and neck kinematics, to investigate differences between subjects with non-specific neck pain and whiplash associated disorders (WAD), and to evaluate the potential of objective movement analysis as a decision support during diagnosis and follow-up of patients with neck pain. LÄS MER

3. 2. Biomechanical methods and error analysis related to chronic musculoskeletal pain

   Författare :Fredrik Öhberg; Mats Djupsjöbacka; Åke Öberg; Högskolan i Gävle; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; cervical spine; ensemble theory; error analysis; helical axis; kinematics; movement analysis; neural coding; pattern recognition; spike sorting; whiplash; Medical technology; Medicinsk teknik;

   Sammanfattning : Background Spinal pain is one of humanity’s most frequent complaints with high costs for the individual and society, and is commonly related to spinal disorders. There are many origins behind these disorders e.g., trauma, disc hernia or of other organic origins. LÄS MER

4. 3. Movement strategies and dynamic knee control after anterior cruciate ligament injury : a three-dimensional biomechanical analysis

   Författare :Jonas L. Markström; Charlotte K. Häger; Eva Tengman; Helena Grip; Lina Schelin; Jim Richards; Umeå universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Anterior cruciate ligament; biomechanics; kinematics; kinetics; finite helical axis; injury prevention; sports; reliability; agreement; one-leg hops; functional data analysis; physiotherapy; fysioterapi;

   Sammanfattning : Background: Rupture of the anterior cruciate ligament (ACL) is common and mainly occurs in non-contact situations in sports, often due to momentarily poor movement control. Assessment of movement quality during sport-like tasks iscrucial to understand how to decrease the high risk of reinjury for ACL-injured persons, but also how to prevent primary injury. LÄS MER

5. 4. Theory of X-ray Absorption Spectra and Spin Transfer Torque

   Författare :Ola Wessely; Olle Eriksson; Lars Nordström; Eric Shirley; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Physics; First principles calculations; X-ray absorption spectroscopy; Carbon nanotubes; Helical spin density waves; Hydrogen storage; Spin transfer torque; Fysik; Physics; Fysik;

   Sammanfattning : The subjects of the thesis are theoretical first principles calculations of X-ray absorption (XA) spectra and current induced spin transfer torque. XA spectra calculated from atomic multiplet theory and from band structure calculations, based on density functional theory for La0.7Sr0.3MnO3 have been compared to experiment. LÄS MER

7. 5. Optical Investigations of Chiral Liquid Crystals

   Författare :Anders Dahlgren; Chalmers tekniska högskola; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; antiferroelectric; de Vries theory; ferroelectric; optical activity; chiral; dielectric tensor; unwinding; liquid crystal; helicoidal; selective reflection;

   Sammanfattning : Optical investigations of course involve experimental work, but a theoretical basis is also needed. The first chapter can hopefully can give the non-expert an insight into the science of liquid crystals. Liquid crystals are optically birefringent, and a review of the phenomenon of birefringence follows in chapter 2. LÄS MER