Sökning: "electromagnetic fields"

Visar resultat 11 - 15 av 170 avhandlingar innehållade orden electromagnetic fields.

1. 11. Office work and physical factors : health aspects of electromagnetic fields and light

   Författare :Monica Sandström; Kjell Hansson Mild; Gunnar Nordberg; Umeå universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Facial skin symptoms; office illness; electrical hypersensitivity; physical environment; flicker; jitter; neurophysiological effects;

   Sammanfattning : The overall aim of this thesis is to increase our knowledge of the physical environment of office workers with special focus on electromagnetic fields and to address the question of whether electromagnetic fields can directly or indirectly contribute to symptoms or discomfort among video display terminal ( VDT) workers. Furthermore, we have measured light modulation from various commonly used light sources in laboratory conditions and, as a second step, used modulated light as stimulus for provocation of neurophysiological responses in persons with perceived “electrical hypersensitivity” (EHS). LÄS MER

3. 12. Electromagnetic Fields in Moving and Inhomogeneous Media

   Författare :Paul Piwnicki; KTH; []
   Nyckelord :Moving Media; Light; Genaral Relativity;

   Sammanfattning : The present thesis deals with electromagnetic effectscreated by the motion or inhomogeneity of a dielectricmedium.In the first paper the quantum R\"ontgen effect isdiscussed. Here a rotating Bose-Einstein condensate -- oranother kind of quantum fluid -- is placed in a chargedcapacitor. The medium's rotation creates a magnetic field. LÄS MER

4. 13. Idiopathic environmental intolerance attributed to electromagnetic fields : physiological and psychological aspects

   Författare :Amanda Johansson; Lena Hillert; Umeå universitet; []
   Nyckelord :electrical hypersensitivity; EHS; mobile phone; MP; heart rate variability; HRV; provocation study; radiofrequency field; Occupational and Environmental Medicine; arbets- och miljömedicin;

   Sammanfattning : This thesis aims to increase the knowledge on people with symptoms attributed to electromagnetic fields (EMF) by investigating the effects of EMF exposure and by additional description of the heterogeneous group of people reporting EMF-related symptoms. The effect of mobile phone (MP)-like radio frequency (RF) fields on symptoms, autonomic nervous system (ANS) parameters, short-term memory, and reaction time in persons with MP-related symptoms (MP participants) was investigated in a provocation study. LÄS MER

5. 14. Occupational exposure to electromagnetic fields and chronic diseases

   Författare :Niclas Håkansson; Karolinska Institutet; Karolinska Institutet; []
   Nyckelord :Electromagnetic fields; chronic diseases; epidemiology; occupation; cancer diseases; neurodegenerative diseases; cardiovascular diseases.;

   Sammanfattning : This thesis consider two exposures from the electromagnetic spectrum extremely low-frequency magnetic fields (ELF MF) and ultraviolet (UV) radiation. ELF MF are the lowest and UV radiation ranges among the highest frequencies of non-ionizing radiation. The exposure prevalence of these fields is high in the general population. LÄS MER

7. 15. Directional Decomposition in Anisotropic Heterogeneous Media for Acoustic and Electromagnetic Fields

   Författare :B. Lars G. Jonsson; KTH; []
   Nyckelord :directional wave-field decomposition; wave splitting; spectral reduction; aourstic anisotropy; electromagnetic anisotropy; generalized eigenvalue problem;

   Sammanfattning : Directional wave-field decomposition for heterogeneousanisotropic media with in-stantaneous response is establishedfor both the acoustic and the electromagnetic equations.We derive a sufficient condition for ellipticity of thesystem's matrix in the Laplace domain and show that theconstruction of the splitting matrix via a Dunford-Taylorintegral over the resolvent of the non-compact, non-normalsystem's matrix is well de ned. LÄS MER