Article
Refine
Year of publication
- 2024 (35)
- 2023 (66)
- 2022 (80)
- 2021 (86)
- 2020 (102)
- 2019 (97)
- 2018 (85)
- 2017 (72)
- 2016 (79)
- 2015 (83)
- 2014 (93)
- 2013 (97)
- 2012 (82)
- 2011 (130)
- 2010 (122)
- 2009 (121)
- 2008 (103)
- 2007 (94)
- 2006 (86)
- 2005 (99)
- 2004 (131)
- 2003 (74)
- 2002 (92)
- 2001 (88)
- 2000 (84)
- 1999 (88)
- 1998 (82)
- 1997 (79)
- 1996 (70)
- 1995 (68)
- 1994 (77)
- 1993 (51)
- 1992 (48)
- 1991 (25)
- 1990 (35)
- 1989 (38)
- 1988 (54)
- 1987 (32)
- 1986 (18)
- 1985 (32)
- 1984 (18)
- 1983 (17)
- 1982 (26)
- 1981 (18)
- 1980 (35)
- 1979 (23)
- 1978 (30)
- 1977 (14)
- 1976 (13)
- 1975 (10)
- 1974 (3)
- 1972 (2)
- 1971 (1)
- 1968 (1)
Institute
- Fachbereich Medizintechnik und Technomathematik (1361)
- INB - Institut für Nano- und Biotechnologien (503)
- Fachbereich Chemie und Biotechnologie (474)
- Fachbereich Elektrotechnik und Informationstechnik (414)
- IfB - Institut für Bioengineering (412)
- Fachbereich Energietechnik (361)
- Fachbereich Luft- und Raumfahrttechnik (254)
- Fachbereich Maschinenbau und Mechatronik (152)
- Fachbereich Wirtschaftswissenschaften (116)
- Fachbereich Bauingenieurwesen (69)
Language
- English (3289) (remove)
Document Type
- Article (3289) (remove)
Keywords
- Einspielen <Werkstoff> (7)
- avalanche (5)
- Earthquake (4)
- FEM (4)
- Finite-Elemente-Methode (4)
- LAPS (4)
- additive manufacturing (4)
- biosensors (4)
- field-effect sensor (4)
- frequency mixing magnetic detection (4)
Given industrial applications, the costs for the operation and maintenance of a pump system typically far exceed its purchase price. For finding an optimal pump configuration which minimizes not only investment, but life-cycle costs, methods like Technical Operations Research which is based on Mixed-Integer Programming can be applied. However, during the planning phase, the designer is often faced with uncertain input data, e.g. future load demands can only be estimated. In this work, we deal with this uncertainty by developing a chance-constrained two-stage (CCTS) stochastic program. The design and operation of a booster station working under uncertain load demand are optimized to minimize total cost including purchase price, operation cost incurred by energy consumption and penalty cost resulting from water shortage. We find optimized system layouts using a sample average approximation (SAA) algorithm, and analyze the results for different risk levels of water shortage. By adjusting the risk level, the costs and performance range of the system can be balanced, and thus the
system’s resilience can be engineered
Optimisation of a urea selective catalytic reduction system with a coated ceramic mixing element
(2017)
The application of mathematical optimization methods for water supply system design and operation provides the capacity to increase the energy efficiency and to lower the investment costs considerably. We present a system approach for the optimal design and operation of pumping systems in real-world high-rise buildings that is based on the usage of mixed-integer nonlinear and mixed-integer linear modeling approaches. In addition, we consider different booster station topologies, i.e. parallel and series-parallel central booster stations as well as decentral booster stations. To confirm the validity of the underlying optimization models with real-world system behavior, we additionally present validation results based on experiments conducted on a modularly constructed pumping test rig. Within the models we consider layout and control decisions for different load scenarios, leading to a Deterministic Equivalent of a two-stage stochastic optimization program. We use a piecewise linearization as well as a piecewise relaxation of the pumps’ characteristics to derive mixed-integer linear models. Besides the solution with off-the-shelf solvers, we present a problem specific exact solving algorithm to improve the computation time. Focusing on the efficient exploration of the solution space, we divide the problem into smaller subproblems, which partly can be cut off in the solution process. Furthermore, we discuss the performance and applicability of the solution approaches for real buildings and analyze the technical aspects of the solutions from an engineer’s point of view, keeping in mind the economically important trade-off between investment and operation costs.
The immobilization of NAD+-dependent dehydrogenases, in combination with a diaphorase, enables the facile development of multiparametric sensing devices. In this work, an amperometric biosensor array for simultaneous determination of ethanol, formate, d- and l-lactate is presented. Enzyme immobilization on platinum thin-film electrodes was realized by chemical cross-linking with glutaraldehyde. The optimization of the sensor performance was investigated with regard to enzyme loading, glutaraldehyde concentration, pH, cofactor concentration and temperature. Under optimal working conditions (potassium phosphate buffer with pH 7.5, 2.5 mmol L-1 NAD+, 2.0 mmol L-1 ferricyanide, 25 °C and 0.4% glutaraldehyde) the linear working range and sensitivity of the four sensor elements was improved. Simultaneous and cross-talk free measurements of four different metabolic parameters were performed successfully. The reliable analytical performance of the biosensor array was demonstrated by application in a clarified sample of inoculum sludge. Thereby, a promising approach for on-site monitoring of fermentation processes is provided.