Sökning: "light flicker"

Hittade 5 avhandlingar innehållade orden light flicker.

1. 1. Retinal glucose metabolism and blood flow : Effects of photic stimulation

   Författare :Lin Wang; Uppsala universitet; []
   Nyckelord :MEDICIN OCH HÄLSOVETENSKAP; MEDICAL AND HEALTH SCIENCES; Physiology and anatomy; blood flow; darkness; flicker; glucose oxidation; glycolysis; lactate; light; nitric oxide; optic nerve; retina; Fysiologi och anatomi; Physiology and pharmacology; Fysiologi och farmakologi; Physiology; fysiologi;

   Sammanfattning : Retinal glucose metabolism was investigated under different light conditions in cats,pigs and rabbits. Glycolysis and glucose oxidation in the outer and inner parts of theretina were assessed by determining arteriovenous concentration differences foroxygen, glucose and lactate, as well as local blood flow. LÄS MER

3. 2. 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

4. 3. On Tracing Flicker Sources and Classification of Voltage Disturbances

   Författare :Peter Axelberg; Högskolan i Borås; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; power transmission and distribution; digital signal processing; power quality monitoring; light flicker; power system disturbance; support vector machines; Medicinteknik; voltage dips;

   Sammanfattning : Developments in measurement technology, communication and data storage have resulted in measurement systems that produce large amount of data. Together with the long existing need for characterizing the performance of the power system this has resulted in demand for automatic and efficient information-extraction methods. LÄS MER

5. 4. On voltage fluctuations in low voltage grids – characterization, propagation and impact on LED lamps

   Författare :Elena Gutierrez Ballesteros; Sarah Rönnberg; Aurora Gil de Castro; Izaskun Azcarate; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; household devices; LED lamps; light flicker; low voltage grid; voltage fluctuations; Electric Power Engineering; Elkraftteknik;

   Sammanfattning : The work presented focuses on voltage fluctuations produced by household devices and their impact on the light output of LED lamps. Voltage fluctuations can produce unsteadiness on the light intensity of the lamps, so-called light flicker. An observer may or may not experience light flicker, depending on e.g. LÄS MER

7. 5. Propagation of Supraharmonics in Low-Voltage Networks

   Författare :Angela Espin Delgado; Sarah Rönnberg; Math Bollen; Jos Knockaert; Luleå tekniska universitet; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; supraharmonics; waveform distortion; low-voltage; high-frequency harmonics; Electric Power Engineering; Elkraftteknik;

   Sammanfattning : The need for measures towards a sustainable use of energy has incited the proliferation of devices and systems for the efficient use of electricity. Energy-efficient appliances, equipment for the electrification of transportation, electricity generators from renewable energy sources, and communication protocols, e.g. LÄS MER