Article
Refine
Year of publication
- 2023 (2)
- 2022 (6)
- 2021 (6)
- 2020 (9)
- 2019 (7)
- 2018 (7)
- 2017 (9)
- 2016 (8)
- 2015 (4)
- 2014 (4)
- 2013 (4)
- 2012 (5)
- 2011 (12)
- 2010 (9)
- 2009 (8)
- 2008 (10)
- 2007 (19)
- 2006 (30)
- 2005 (10)
- 2004 (13)
- 2003 (13)
- 2002 (5)
- 2001 (8)
- 2000 (11)
- 1999 (8)
- 1998 (10)
- 1997 (3)
- 1996 (10)
- 1995 (9)
- 1994 (9)
- 1993 (6)
- 1992 (8)
- 1991 (6)
- 1990 (3)
- 1989 (3)
- 1988 (7)
- 1987 (4)
- 1986 (2)
- 1985 (3)
- 1984 (7)
- 1983 (3)
- 1982 (2)
- 1981 (2)
- 1980 (2)
- 1979 (1)
- 1977 (1)
- 1972 (1)
- 1971 (1)
Document Type
- Article (330) (remove)
Keywords
- Haustechnik (2)
- Heizung (2)
- Klimatechnik (2)
- Lüftung (2)
- Lüftungstechnik (2)
- Abluft (1)
- Algal Turf Scrubber (1)
- Algal–bacterial bioflm (1)
- Anammox (1)
- Anschlüsse an Stahlbeton (1)
- Biogas (1)
- Brandfall (1)
- Circular bioeconomy (1)
- EN 1993-1-2 (1)
- Eingespannte Stützen und Träger (1)
- Einspanntiefen (1)
- Forschung, pränormativ (1)
- Hazard assessment (1)
- Landslide tsunamis (1)
- Large scale tests (1)
Institute
- Fachbereich Bauingenieurwesen (330) (remove)
Zur Anwendung des Eurocode 3 Teil 1-2 für die Heißbemessung und Anregungen für dessen Novellierung
(2016)
Die Eurocodes werden bis zum Jahr 2020 im Europäischen Komitee für Normung (CEN), Technisches Komitee TC 250, überarbeitet. In Vorbereitung auf die Eurocode-Novellierung haben engagierte Ingenieure im Rahmen der Initiative PraxisRegeln Bau (PRB) die für die praktische Anwendung häufig genutzten Teile des Eurocode 3 untersucht. Mit dem Ziel, die Praxistauglichkeit des Eurocode 3 für die Heißbemessung zu verbessern, wurden die bestehende Norm EN 1993 Teil 1-2 insbesondere in Bezug auf die Anwenderfreundlichkeit analysiert und Vorschläge für die europäische Novellierung erarbeitet. Die Analysen zeigen, dass durch Umstrukturierungen und durch die Einführung von Tabellen die Verständlichkeit und Anwenderfreundlichkeit der Regeln für die Heißbemessung bedeutend erhöht werden können.
Optical flow estimation is known from Computer Vision where it is used to determine obstacle movements through a sequence of images following an assumption of brightness conservation. This paper presents the first study on application of the optical flow method to aerated stepped spillway flows. For this purpose, the flow is captured with a high-speed camera and illuminated with a synchronized LED light source. The flow velocities, obtained using a basic Horn–Schunck method for estimation of the optical flow coupled with an image pyramid multi-resolution approach for image filtering, compare well with data from intrusive conductivity probe measurements. Application of the Horn–Schunck method yields densely populated flow field data sets with velocity information for every pixel. It is found that the image pyramid approach has the most significant effect on the accuracy compared to other image processing techniques. However, the final results show some dependency on the pixel intensity distribution, with better accuracy found for grey values between 100 and 150.
Numerische Strömungssimulationen von Fließgewässern : Praxisanwendungen und zukünftige Entwicklungen
(2015)
Block ramps are ecologically oriented drop structures with adequate energy dissipation and partially moderate flow velocities. A special case is given with crossbar block ramps, where the upstream and downstream level difference is reduced by a series of basins. To prevent the total structure from failing, the stability of single boulders within the crossbars and the bed material in between must be guaranteed. The present paper addresses the stability of bed material and scour development for various flow regimes. Any bed material erosion may affect the stability of the crossbar boulders, which in turn can result in major damages of the ramp. Therefore new design approaches are developed to choose an appropriate bed material size and to avoid failures of crossbar block ramp structures.
Abwasserwärmenutzung
(2013)
As part of a novel approach to automatic sewer inspection, this paper presents a robust algorithm for automatic flow line detection. A large image repository is obtained from about 50,000 m sewers to represent the high variability of real world sewer systems. Automatic image processing combines Canny edge detection, Hough transform for straight lines and cost minimization using Dijkstra's shortest path algorithm. Assuming that flow lines are mostly smoothly connected horizontal structures, piecewise flow line delineation is reduced to a process of selecting adjacent line candidates. Costs are derived from the gap between adjacent candidates and their reliability. A single parameter α enables simple control of the algorithm. The detected flow line may precisely follow the segmented edges (α = 0.0) or minimize gaps at joints (α = 1.0). Both, manual and ground truth-based analysis indicate that α = 0.8 is optimal and independent of the sewer's material. The algorithm forms an essential step to further automation of sewer inspection.
Since several decades, dam-break waves have been of main research interest. Mathematical approaches have been developed by analytical, physical and numerical models within the past 120 years. During the past 10 years, the number of research investigations has increased due to improved measurement techniques as well as significantly increased computer memories and performances. In this context, the present research deals with the initial stage of two-dimensional dam-break waves by comparing physical and numerical model results as well as analytical approaches. High-speed images and resulting particle image velocimetry calculations are thereby compared with the numerical volume-of-fluid (VOF) method, included in the commercial code FLOW-3D. Wave profiles and drag forces on placed obstacles are analysed in detail. Generally, a good agreement between the laboratory and VOF results is found.