Sökning: "spatial frequency"

Visar resultat 21 - 25 av 330 avhandlingar innehållade orden spatial frequency.

1. 21. Laser diode systems for photodynamic therapy and medical diagnostics

   Författare :Eva Samsöe Andersen; Atomfysik; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; quasi-phasematching; photodynamic therapy; laser-induced fluorescence; medical laser systems.; Histology; cytochemistry; histochemistry; tissue culture; Histologi; Laserteknik; Laser technology; cytokemi; histokemi; vävnadskultur; Diagnostik; Diagnostics; second harmonic generation; pulsed lasers; spatial filtering; Diode lasers; optical feedback; Fysicumarkivet A:2004:Samsöe Andersen;

   Sammanfattning : This work concerns techniques for improvement of the coherence properties of diode lasers so that they may be used in two specific medical applications: (Interstitial) photodynamic therapy (PDT) and laser-induced fluorescence diagnostics. In the first application, spatial coherence is crucial, since the treatment light should be delivered through relatively thin optical fibers to optimize treatment and to facilitate minimally invasive treatment. LÄS MER

3. 22. Short Pulses in Engineered Nonlinear Media

   Författare :Stefan Holmgren; Fredrik Laurell; Derryck Reid; KTH; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; nonlinear optics; KTiOPO4; frequency conversion; mode-locked lasers; ultra-fast lasers; visible lasers; short pulses; ultrafast nonlinear optics; diagnostic applications of nonlinear optics; nonlinear optical materials; Physics; Fysik;

   Sammanfattning : Short optical pulses and engineered nonlinear media is a powerful combination. Mode locked pulses exhibit high peak powers and short pulse duration and the engineered ferro-electric KTiOPO4 facilitates several different nonlinear processes. LÄS MER

4. 23. Dynamics of the cold surface layer of polythermal Storglaciären, Sweden

   Författare :Rickard Pettersson; Per Holmlund; Peter Janssson; Jens-Ove Näslund; Regine Hock; Helgi Björnsson; Stockholms universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; polythermal glacier; cold surface layer; ground-penetrating radar; spatial variability; water content; Storglaciären; Earth sciences; Geovetenskap;

   Sammanfattning : Polythermal glaciers, i.e. glaciers with a combination of ice at and below the freezing point, are widespread in arctic and subarctic environments. The polythermal structure has major implications for glacier hydrology, ice flow and glacial erosion. LÄS MER

5. 24. Hybrid and Dynamic Substructuring Methods for Energy Flow Analysis

   Författare :Anders Wilson; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; fractional derivatives; structural modeling; mid-frequency; finite element method FEM; vibro-acoustics; statistical energy analysis SEA; dynamic substructuring; hybrid analysis; viscoelasticity;

   Sammanfattning : Modeling techniques and solution tools to analyze the dynamic and vibro-acoustic behavior of complex built-up structures are matters of increasing interest, especially for thin walled structures as in transportation vehicles, such as automobiles, trucks, trains and aircraft. In structures like these, the reduction of cost, weight, sound and vibration levels are primary issues for research and development. LÄS MER

7. 25. Uncommon Ground : Urban Form and Social Territory

   Författare :Eva Minoura; Daniel Koch; Meta Berghauser Pont; Alexander Ståhle; Stephen Marshall; KTH; []
   Nyckelord :HUMANIORA; HUMANITIES; territoriality; interface; social sustainability; morphology; commons; stewardship; open space; yards; spatial analysis; Architecture; Arkitektur;

   Sammanfattning : Implicit in any urban design is a negotiation between public and private interests. Such a negotiation is articulated and made legible in the facades, fences and even more subtle edges separating this from that. A complex variety of spatial situations are produced depending on how spaces are framed, how interfaces are materialized. LÄS MER