@inproceedings{AuelAlbayrakBoes2014, author = {Auel, C. and Albayrak, I. and Boes, R.M.}, title = {Bedload particle velocity in supercritical open channel flows}, series = {Proc. 7th River Flow, Int. Conference on Fluvial Hydraulics (Schleiss et al. eds.)}, booktitle = {Proc. 7th River Flow, Int. Conference on Fluvial Hydraulics (Schleiss et al. eds.)}, publisher = {Taylor and Francis}, isbn = {978-1-138-02674-2}, doi = {10.25974/fhms-15157}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:836-opus-151579}, pages = {923 -- 931}, year = {2014}, abstract = {Single glass sphere motion recordings were conducted in a transitional-rough bed open channel at steady and highly supercritical flow similar to hydraulic conditions in sediment bypass tunnels. A high speed camera with a maximum resolution of 2,560 × 2,160 pixels was used to record the movement of bedload particles with diameters of D = 5.3, 10.3 and 17.5 mm. An in-house developed Particle Tracking Velocimetry (PTV) program was used to determine the transport mode and velocities of each particle for a wide range of Froude numbers up to Fo = 6. The relative roughness defined as the ratio of the bed roughness height ks to the water depth h varied from ks/h = 0.02-0.03. Particles were observed to move in rolling and saltation modes depending on the Shields number. The particle velocity shows a linearly increasing relationship with both friction velocity and Froude number nearly independent on the particle diameter. A linear relationship was also found between rolling and saltating particle velocities indicating that particle velocity does not depend on the transport mode in the range of the investigated hydraulic conditions. Scaling of particle velocity with the wave celerity plotted as a function of the Froude number adequately merged external data sets with the present data. As a consequence, a linear fit for a large Froude number range was obtained.}, language = {en} } @inproceedings{BoesAuelHagemannetal.2014, author = {Boes, R.M. and Auel, C. and Hagemann, M. and Albayrak, I.}, title = {Sediment bypass tunnels to mitigate reservoir sedimentation and restore sediment continuity}, series = {Reservoir Sedimentation}, booktitle = {Reservoir Sedimentation}, publisher = {Taylor and Francis Group}, address = {London, UK}, isbn = {978-1-138-02675-9}, doi = {10.25974/fhms-15156}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:836-opus-151569}, pages = {221 -- 228}, year = {2014}, abstract = {Worldwide, a large number of reservoirs impounded by dams are rapidly filling up with sediments. As on a global level the loss of reservoir volume due to sedimentation increases faster than the creation of new storage volume, the sustainability of reservoirs may be questioned if no countermeasures are taken. This paper gives an overview of the amount and the processes of reservoir sedimentation and its impact on dams and reservoirs. Furthermore, sediment bypass tunnels as a countermeasure for small to medium sized reservoirs are discussed with their pros and cons. The issue of hydroabrasion is highlighted, and the main design features to be applied for sediment bypass tunnels are given.}, language = {en} } @article{Lorek2014, author = {Lorek, Sylvia}, title = {Veblen's contribution to the analysis of (un-) sustainable consumption - Overvalued and underestimated}, series = {European Journal of Economic and Social Systems}, volume = {26}, journal = {European Journal of Economic and Social Systems}, number = {1-2}, doi = {10.3166/EJESS.26.149-172}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:836-opus-106424}, pages = {149 -- 172}, year = {2014}, abstract = {Veblen's concept of conspicuous consumption is often cited to explain why consumption habits in our consumer societies tend to be unsustainable and ever increasing. However, much more than blaming individual consumption habits Veblen sharply analyzed quite some of the societal and economic forces which drive the framework conditions for un-sustainable consumption: the vested interests and the absentee ownership. The paper follows the path Veblen's thoughts have taken trough economic and social literature over the last centuryand highlights how the actual sustainable consumption debate could make better use of Veblen's insights e.g. in requesting the constitutive institutions for property. Opportunities for Strong Sustainable Consumption obviously presuppose radical changes, social innovations and thinking out of the box.}, language = {en} } @article{LorekSpangenberg2014, author = {Lorek, Sylvia and Spangenberg, Joachim}, title = {Sustainable Consumption within a sustainable economy - beyond green growth and green economies}, series = {Journal of Cleaner Production}, volume = {63}, journal = {Journal of Cleaner Production}, doi = {10.25974/fhms-6154}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:836-opus-61544}, pages = {33 -- 44}, year = {2014}, language = {en} } @incollection{DellmannJimenezPorras2014, author = {Dellmann, Frank and Jim{\´e}nez Porras, Gerardo}, title = {Training of university lecturers at National University of Costa Rica in competency-based learning and testing, University of M{\"u}nster, Germany}, series = {National and Institutional Strategies - European Higher Education Institutions Collaboration with America}, booktitle = {National and Institutional Strategies - European Higher Education Institutions Collaboration with America}, doi = {10.25974/fhms-5794}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:836-opus-57943}, publisher = {FH M{\"u}nster - University of Applied Sciences}, pages = {109 -- 117}, year = {2014}, language = {en} } @article{KazasidisWittrock2014, author = {Kazasidis, Orestis and Wittrock, Ulrich}, title = {Interferometric measurement of the temperature coefficient of the refractive index dn/dT and the coefficient of thermal expansion of Pr:YLF laser crystals}, series = {Opt. Expr.}, volume = {22}, journal = {Opt. Expr.}, publisher = {Optical Society of America}, doi = {10.25974/fhms-772}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:836-opus-7720}, pages = {30683 -- 30696}, year = {2014}, abstract = {We report interferometric measurements of the temperature coefficient of the refractive index (dn=dT) and the coefficient of thermal expansion (a) of a praseodymium-doped yttrium lithium fluoride (Pr:YLF) crystal and of a fused silica reference sample. Our phase-resolved interferometric method yields a large number of data points and thus allows a precise measurement and a good error estimation. Furthermore, both dn=dT and a are obtained simultaneously from a single measurement which reduces errors that can occur in separate measurements. Over the temperature range from 20 °C to 80 °C, the value of dn=dT of Pr:YLF decreases from -5.2 x 10-6 /K to -6.2 x 10-6 /K for the ordinary refractive index and from -7.6 x 10-6 /K to -8.6 x 10-6 /K for the extraordinary refractive index. The coefficient of thermal expansion for the a-axis of Pr:YLF increases from 16.4 x 10-6 /K to 17.8 x 10-6 /K over the same temperature range.}, language = {en} } @inproceedings{RauschVerpoortWittrock2014, author = {Rausch, Peter and Verpoort, Sven and Wittrock, Ulrich}, title = {Performance verification and environmental testing of a unimorph deformable mirror for space applications.}, series = {Proceedings of the 10th International Conference on Space Optics - ICSO, Tenerife, Spain}, booktitle = {Proceedings of the 10th International Conference on Space Optics - ICSO, Tenerife, Spain}, publisher = {FH M{\"u}nster}, doi = {10.25974/fhms-771}, url = {http://nbn-resolving.de/urn:nbn:de:hbz:836-opus-7716}, year = {2014}, abstract = {Concepts for future large space telescopes require an active optics system to mitigate aberrations caused by thermal deformation and gravitational release. Such a system would allow on-site correction of wave-front errors and ease the requirements for thermal and gravitational stability of the optical train. In the course of the ESA project "Development of Adaptive Deformable Mirrors for Space Instruments" we have developed a unimorph deformable mirror designed to correct for low-order aberrations and dedicated to be used in space environment. We briefly report on design and manufacturing of the deformable mirror and present results from performance verifications and environmental testing.}, language = {en} }