Article
Refine
Year of publication
- 2009 (199) (remove)
Institute
- Fachbereich Medizintechnik und Technomathematik (76)
- INB - Institut für Nano- und Biotechnologien (32)
- Fachbereich Wirtschaftswissenschaften (31)
- IfB - Institut für Bioengineering (28)
- Fachbereich Elektrotechnik und Informationstechnik (23)
- Fachbereich Chemie und Biotechnologie (18)
- Fachbereich Energietechnik (15)
- Fachbereich Luft- und Raumfahrttechnik (9)
- Fachbereich Bauingenieurwesen (8)
- Fachbereich Maschinenbau und Mechatronik (8)
Document Type
- Article (199) (remove)
Keywords
- Atomausstieg (1)
- Blitzschutz (1)
- EGG (1)
- Europäische Energiepolitik (1)
- Hühnerzucht (1)
- Kernenergie (1)
- Larynx position (1)
- Tomography (1)
- Transfer impedance (1)
- Unterhaltung (1)
Chicks off speed
(2009)
Embedding fuzzy controllers in golog / Ferrein, Alexander ; Schiffer, Stefan ; Lakemeyer, Gerhard
(2009)
The powerful avalanche simulation toolbox RAMMS (Rapid Mass Movements) is based on a depth-averaged
hydrodynamic system of equations with a Voellmy-Salm friction relation. The two empirical friction parameters
μ and correspond to a dry Coulomb friction and a viscous resistance, respectively. Although μ and lack a
proper physical explanation, 60 years of acquired avalanche data in the Swiss Alps made a systematic calibration
possible. RAMMS can therefore successfully model avalanche flow depth, velocities, impact pressure and run
out distances. Pudasaini and Hutter (2003) have proposed extended, rigorously derived model equations that
account for local curvature and twist. A coordinate transformation into a reference system, applied to the actual
mountain topography of the natural avalanche path, is performed. The local curvature and the twist of the
avalanche path induce an additional term in the overburden pressure. This leads to a modification of the Coulomb
friction, the free-surface pressure gradient, the pressure induced by the channel, and the gravity components
along and normal to the curved and twisted reference surface. This eventually guides the flow dynamics and
deposits of avalanches. In the present study, we investigate the influence of curvature on avalanche flow in
real mountain terrain. Simulations of real avalanche paths are performed and compared for the different models
approaches. An algorithm to calculate curvature in real terrain is introduced in RAMMS. This leads to a curvature
dependent friction relation in an extended version of the Voellmy-Salm model equations. Our analysis provides
yet another step in interpreting the physical meaning and significance of the friction parameters used in the
RAMMS computational environment.
Expeditious building of ring-porous earlywood vessel chronologies without loosing signal information
(2009)
Next Generation Access Networks: Why is there a higher risk of investment and how to deal with it?
(2009)
Das Wohnungsrecht : Ausübungshindernis, Sozialhilferegress und Fremdvermietung bei Übergabeverträgen
(2009)
This study demonstrates the feasibility of applying free-breathing, cardiac-gated, susceptibility-weighted fast spin-echo imaging together with black blood preparation and navigator-gated respiratory motion compensation for anatomically accurate T₂ mapping of the heart. First, T₂ maps are presented for oil phantoms without and with respiratory motion emulation (T₂ = (22.1 ± 1.7) ms at 1.5 T and T₂ = (22.65 ± 0.89) ms at 3.0 T). T₂ relaxometry of a ferrofluid revealed relaxivities of R2 = (477.9 ± 17) mM⁻¹s⁻¹ and R2 = (449.6 ± 13) mM⁻¹s⁻¹ for UFLARE and multiecho gradient-echo imaging at 1.5 T. For inferoseptal myocardial regions mean T₂ values of 29.9 ± 6.6 ms (1.5 T) and 22.3 ± 4.8 ms (3.0 T) were estimated. For posterior myocardial areas close to the vena cava T₂-values of 24.0 ± 6.4 ms (1.5 T) and 15.4 ± 1.8 ms (3.0 T) were observed. The merits and limitations of the proposed approach are discussed and its implications for cardiac and vascular T₂-mapping are considered.
Fundamentals and ignition of a microplasma at 2.45 GHZ / Holtrup, Stephan ; Heuermann, Holger
(2009)