@article{Staat2005, author = {Staat, Manfred}, title = {Local and global collapse pressure of longitudinally flawed pipes and cylindrical vessels}, year = {2005}, abstract = {Limit loads can be calculated with the finite element method (FEM) for any component, defect geometry, and loading. FEM suggests that published long crack limit formulae for axial defects under-estimate the burst pressure for internal surface defects in thick pipes while limit loads are not conservative for deep cracks and for pressure loaded crack-faces. Very deep cracks have a residual strength, which is modelled by a global collapse load. These observations are combined to derive new analytical local and global collapse loads. The global collapse loads are close to FEM limit analyses for all crack dimensions.}, subject = {Finite-Elemente-Methode}, language = {en} } @article{Weigand1992, author = {Weigand, Christoph}, title = {Economic Machine Adjustment in the Case of Product Screening .E.v.Collani, Ch. Weigand}, series = {Statistical Papers. 33 (1992)}, journal = {Statistical Papers. 33 (1992)}, pages = {171 -- 184}, year = {1992}, language = {en} } @article{Staat2004, author = {Staat, Manfred}, title = {Plastic collapse analysis of longitudinally flawed pipes and vessels}, year = {2004}, abstract = {Improved collapse loads of thick-walled, crack containing pipes and vessels are suggested. Very deep cracks have a residual strength which is better modelled by a global limit load. In all burst tests, the ductility of pressure vessel steels was sufficiently high whereby the burst pressure could be predicted by limit analysis with no need to apply fracture mechanics. The relative prognosis error increases however, for long and deep defects due to uncertainties of geometry and strength data.}, subject = {Druckbeh{\"a}lter}, language = {en} } @article{StaatSchwartzLangetal.2003, author = {Staat, Manfred and Schwartz, M. and Lang, H. and Wirtz, K. and Heitzer, M.}, title = {Design by Analysis of Pressure Components by non-linear Optimization}, series = {The 10th International Conference on Pressure Vessel Technology, July 7-10, 2003, Vienna, Austria, Proceedings ICPVT-10 / Zeman, J. L. [ed]}, journal = {The 10th International Conference on Pressure Vessel Technology, July 7-10, 2003, Vienna, Austria, Proceedings ICPVT-10 / Zeman, J. L. [ed]}, publisher = {{\"O}GS, {\"O}sterreichische Gesellschaft f{\"u}r Schweißtechnik}, address = {Wien}, isbn = {3950152814}, pages = {59 -- 65}, year = {2003}, language = {en} } @article{StaatHeitzer2002, author = {Staat, Manfred and Heitzer, M.}, title = {Limit and Shakedown Analysis with Uncertain Data}, series = {Stochastic optimization techniques : numerical methods and technical applications / Marti, K. [ed]}, journal = {Stochastic optimization techniques : numerical methods and technical applications / Marti, K. [ed]}, publisher = {Springer}, address = {Heidelberg}, isbn = {3-540-42889-5}, pages = {241 -- 254}, year = {2002}, language = {en} } @article{JablonskiMuenstermannNorketal.2021, author = {Jablonski, Melanie and M{\"u}nstermann, Felix and Nork, Jasmina and Molinnus, Denise and Muschallik, Lukas and Bongaerts, Johannes and Wagner, Torsten and Keusgen, Michael and Siegert, Petra and Sch{\"o}ning, Michael Josef}, title = {Capacitive field-effect biosensor applied for the detection of acetoin in alcoholic beverages and fermentation broths}, series = {physica status solidi (a) applications and materials science}, volume = {218}, journal = {physica status solidi (a) applications and materials science}, number = {13}, publisher = {Wiley-VCH}, address = {Weinheim}, issn = {1862-6319}, doi = {10.1002/pssa.202000765}, pages = {7 Seiten}, year = {2021}, abstract = {An acetoin biosensor based on a capacitive electrolyte-insulator-semiconductor (EIS) structure modified with the enzyme acetoin reductase, also known as butane-2,3-diol dehydrogenase (Bacillus clausii DSM 8716ᵀ), is applied for acetoin detection in beer, red wine, and fermentation broth samples for the first time. The EIS sensor consists of an Al/p-Si/SiO₂/Ta₂O₅ layer structure with immobilized acetoin reductase on top of the Ta₂O₅ transducer layer by means of crosslinking via glutaraldehyde. The unmodified and enzyme-modified sensors are electrochemically characterized by means of leakage current, capacitance-voltage, and constant capacitance methods, respectively.}, language = {en} } @article{FerreinMiesLakemeyer2008, author = {Ferrein, Alexander and Mies, Christoph and Lakemeyer, Gerhard}, title = {Repairing Decision-Theoretic Policies Using Goal-Oriented Planning / Mies, Christoph ; Ferrein, Alexander ; Lakemeyer, Gerhard}, series = {KI 2008: Advances in Artificial Intelligence : 31st Annual German Conference on AI, KI 2008, Kaiserslautern, Germany, September 23-26, 2008. Proceedings}, journal = {KI 2008: Advances in Artificial Intelligence : 31st Annual German Conference on AI, KI 2008, Kaiserslautern, Germany, September 23-26, 2008. Proceedings}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-85844-7}, pages = {267 -- 275}, year = {2008}, language = {en} } @article{StadlerZerlinDigeletal.2008, author = {Stadler, Andreas M. and Zerlin, Kay and Digel, Ilya and B{\"u}ldt, Georg and Zaccai, Guiseppe and Artmann, Gerhard}, title = {Dynamics and interactions of hemoglobin in red blood cells}, series = {Tissue Engineering Part A. 14 (2008), H. 5}, journal = {Tissue Engineering Part A. 14 (2008), H. 5}, isbn = {1937-3341}, pages = {724 -- 724}, year = {2008}, language = {en} } @article{Weigand2009, author = {Weigand, Christoph}, title = {Defining Precisions for Reliable Measurement and Estimation Procedures}, series = {Economic Quality Control. 24 (2009), H. 1}, journal = {Economic Quality Control. 24 (2009), H. 1}, publisher = {De Gruyter}, address = {Berlin}, isbn = {0940-5151}, pages = {5 -- 33}, year = {2009}, language = {en} } @article{Weigand2003, author = {Weigand, Christoph}, title = {Economically Optimal Inspection Policy with Geometrical Adaption}, series = {Journal of Applied Statistics. 30 (2003), H. 5}, journal = {Journal of Applied Statistics. 30 (2003), H. 5}, isbn = {0266-4763}, pages = {555 -- 569}, year = {2003}, language = {en} } @article{Weigand2001, author = {Weigand, Christoph}, title = {Economically Optimal Inspection Policy with Arithmetical Adaption}, series = {Applied stochastic models and data analysis / [10th International Symposium on Applied Stochastic Models and Analysis, June 12-15 2001, Universit{\´e} Technologique de Compi{\`e}gne] ; editors G{\´e}rard Govaert, Jacques Janssen, Nikolaos Limnios.}, journal = {Applied stochastic models and data analysis / [10th International Symposium on Applied Stochastic Models and Analysis, June 12-15 2001, Universit{\´e} Technologique de Compi{\`e}gne] ; editors G{\´e}rard Govaert, Jacques Janssen, Nikolaos Limnios.}, publisher = {Universit{\´e} Technologique de Compi{\`e}gne}, address = {Compi{\`e}gne}, pages = {1010 -- 1015}, year = {2001}, language = {en} } @article{ValeroBungErpicumetal.2022, author = {Valero, Daniel and Bung, Daniel Bernhard and Erpicum, Sebastien and Peltier, Yann and Dewals, Benjamin}, title = {Unsteady shallow meandering flows in rectangular reservoirs: a modal analysis of URANS modelling}, series = {Journal of Hydro-environment Research}, journal = {Journal of Hydro-environment Research}, number = {In Press}, publisher = {Elsevier}, address = {Amsterdam}, issn = {1570-6443}, doi = {10.1016/j.jher.2022.03.002}, year = {2022}, abstract = {Shallow flows are common in natural and human-made environments. Even for simple rectangular shallow reservoirs, recent laboratory experiments show that the developing flow fields are particularly complex, involving large-scale turbulent structures. For specific combinations of reservoir size and hydraulic conditions, a meandering jet can be observed. While some aspects of this pseudo-2D flow pattern can be reproduced using a 2D numerical model, new 3D simulations, based on the unsteady Reynolds-Averaged Navier-Stokes equations, show consistent advantages as presented herein. A Proper Orthogonal Decomposition was used to characterize the four most energetic modes of the meandering jet at the free surface level, allowing comparison against experimental data and 2D (depth-averaged) numerical results. Three different isotropic eddy viscosity models (RNG k-ε, k-ε, k-ω) were tested. The 3D models accurately predicted the frequency of the modes, whereas the amplitudes of the modes and associated energy were damped for the friction-dominant cases and augmented for non-frictional ones. The performance of the three turbulence models remained essentially similar, with slightly better predictions by RNG k-ε model in the case with the highest Reynolds number. Finally, the Q-criterion was used to identify vortices and study their dynamics, assisting on the identification of the differences between: i) the three-dimensional phenomenon (here reproduced), ii) its two-dimensional footprint in the free surface (experimental observations) and iii) the depth-averaged case (represented by 2D models).}, language = {en} } @article{Dachwald2005, author = {Dachwald, Bernd}, title = {Optimization of very-low-thrust trajectories using evolutionary neurocontrol}, series = {Acta Astronautica}, volume = {57}, journal = {Acta Astronautica}, number = {2-8}, publisher = {Elsevier}, address = {Amsterdam [u.a.]}, isbn = {1879-2030}, pages = {175 -- 185}, year = {2005}, abstract = {Searching optimal interplanetary trajectories for low-thrust spacecraft is usually a difficult and time-consuming task that involves much experience and expert knowledge in astrodynamics and optimal control theory. This is because the convergence behavior of traditional local optimizers, which are based on numerical optimal control methods, depends on an adequate initial guess, which is often hard to find, especially for very-low-thrust trajectories that necessitate many revolutions around the sun. The obtained solutions are typically close to the initial guess that is rarely close to the (unknown) global optimum. Within this paper, trajectory optimization problems are attacked from the perspective of artificial intelligence and machine learning. Inspired by natural archetypes, a smart global method for low-thrust trajectory optimization is proposed that fuses artificial neural networks and evolutionary algorithms into so-called evolutionary neurocontrollers. This novel method runs without an initial guess and does not require the attendance of an expert in astrodynamics and optimal control theory. This paper details how evolutionary neurocontrol works and how it could be implemented. The performance of the method is assessed for three different interplanetary missions with a thrust to mass ratio <0.15mN/kg (solar sail and nuclear electric).}, language = {en} } @article{KraemerBongaertsBovenbergetal.2003, author = {Kr{\"a}mer, Marco and Bongaerts, Johannes and Bovenberg, Roel and Kremer, Susanne and M{\"u}ller, Ulrike and Orf, Sonja and Wubbolts, Marcel and Raeven, Leon}, title = {Metabolic engineering for microbial production of shikimic acid}, series = {Metabolic engineering}, volume = {Vol. 5}, journal = {Metabolic engineering}, number = {Iss. 4}, issn = {1096-7184 (E-Journal); 1096-7176 (Print)}, pages = {277 -- 283}, year = {2003}, language = {en} } @article{StaatBaroudTopcuetal.2008, author = {Staat, Manfred and Baroud, G. and Topcu, M. and Sponagel, Stefan}, title = {Soft Materials in Technology and Biology - Characteristics, Properties, and Parameter Identification}, series = {Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.)}, journal = {Bioengineering in Cell and Tissue Research / Artmann, Gerhard M. ; Chien, Shu (Eds.)}, publisher = {Springer}, address = {Berlin}, isbn = {978-3-540-75408-4}, pages = {253 -- 315}, year = {2008}, language = {en} } @article{AkimbekovDigelTastambeketal.2013, author = {Akimbekov, Nuraly S. and Digel, Ilya and Tastambek, K. T. and Zhubanova, A. A.}, title = {Biocompatibility of carbonized rice husk with a rat heart cells line H9c2}, series = {Experimental Biology}, volume = {59}, journal = {Experimental Biology}, number = {3/1}, issn = {1563-0218}, pages = {23 -- 25}, year = {2013}, language = {en} } @article{HoffstadtCheenakulaNikolauszetal.2023, author = {Hoffstadt, Kevin and Cheenakula, Dheeraja and Nikolausz, Marcell and Krafft, Simone and Harms, Hauke and Kuperjans, Isabel}, title = {Design and construction of a new reactor for flexible biomethanation of hydrogen}, series = {Fermentation}, volume = {9}, journal = {Fermentation}, number = {8}, publisher = {MDPI}, address = {Basel}, issn = {2311-5637}, doi = {10.3390/fermentation9080774}, pages = {1 -- 16}, year = {2023}, abstract = {The increasing share of renewable electricity in the grid drives the need for sufficient storage capacity. Especially for seasonal storage, power-to-gas can be a promising approach. Biologically produced methane from hydrogen produced from surplus electricity can be used to substitute natural gas in the existing infrastructure. Current reactor types are not or are poorly optimized for flexible methanation. Therefore, this work proposes a new reactor type with a plug flow reactor (PFR) design. Simulations in COMSOL Multiphysics ® showed promising properties for operation in laminar flow. An experiment was conducted to support the simulation results and to determine the gas fraction of the novel reactor, which was measured to be 29\%. Based on these simulations and experimental results, the reactor was constructed as a 14 m long, 50 mm diameter tube with a meandering orientation. Data processing was established, and a step experiment was performed. In addition, a kLa of 1 h-1 was determined. The results revealed that the experimental outcomes of the type of flow and gas fractions are in line with the theoretical simulation. The new design shows promising properties for flexible methanation and will be tested.}, language = {en} } @article{GoettenFingerHavermannetal.2021, author = {G{\"o}tten, Falk and Finger, Felix and Havermann, Marc and Braun, Carsten and Marino, M. and Bil, C.}, title = {Full configuration drag estimation of short-to-medium range fixed-wing UAVs and its impact on initial sizing optimization}, series = {CEAS Aeronautical Journal}, volume = {12}, journal = {CEAS Aeronautical Journal}, publisher = {Springer}, address = {Berlin}, issn = {1869-5590 (Online)}, doi = {10.1007/s13272-021-00522-w}, pages = {589 -- 603}, year = {2021}, abstract = {The paper presents the derivation of a new equivalent skin friction coefficient for estimating the parasitic drag of short-to-medium range fixed-wing unmanned aircraft. The new coefficient is derived from an aerodynamic analysis of ten different unmanned aircraft used for surveillance, reconnaissance, and search and rescue missions. The aircraft is simulated using a validated unsteady Reynolds-averaged Navier Stokes approach. The UAV's parasitic drag is significantly influenced by the presence of miscellaneous components like fixed landing gears or electro-optical sensor turrets. These components are responsible for almost half of an unmanned aircraft's total parasitic drag. The new equivalent skin friction coefficient accounts for these effects and is significantly higher compared to other aircraft categories. It is used to initially size an unmanned aircraft for a typical reconnaissance mission. The improved parasitic drag estimation yields a much heavier unmanned aircraft when compared to the sizing results using available drag data of manned aircraft.}, language = {en} } @article{BhattaraiStaat2019, author = {Bhattarai, Aroj and Staat, Manfred}, title = {A computational study of organ relocation after laparoscopic pectopexy to repair posthysterectomy vaginal vault prolapse}, series = {Computer Methods in Biomechanics and Biomedical Engineering: Imaging \& Visualization}, journal = {Computer Methods in Biomechanics and Biomedical Engineering: Imaging \& Visualization}, publisher = {Taylor \& Francis}, address = {London}, issn = {2168-1171}, doi = {10.1080/21681163.2019.1670095}, year = {2019}, language = {en} } @article{CapitainRossJonesMoehringetal.2020, author = {Capitain, Charlotte and Ross-Jones, Jesse and M{\"o}hring, Sophie and Tippk{\"o}tter, Nils}, title = {Differential scanning calorimetry for quantification of polymer biodegradability in compost}, series = {International Biodeterioration \& Biodegradation}, volume = {149}, journal = {International Biodeterioration \& Biodegradation}, publisher = {Elsevier}, address = {Amsterdam}, issn = {0964-8305}, doi = {10.1016/j.ibiod.2020.104914}, pages = {In Press, Article number 104914}, year = {2020}, abstract = {The objective of this study is the establishment of a differential scanning calorimetry (DSC) based method for online analysis of the biodegradation of polymers in complex environments. Structural changes during biodegradation, such as an increase in brittleness or crystallinity, can be detected by carefully observing characteristic changes in DSC profiles. Until now, DSC profiles have not been used to draw quantitative conclusions about biodegradation. A new method is presented for quantifying the biodegradation using DSC data, whereby the results were validated using two reference methods. The proposed method is applied to evaluate the biodegradation of three polymeric biomaterials: polyhydroxybutyrate (PHB), cellulose acetate (CA) and Organosolv lignin. The method is suitable for the precise quantification of the biodegradability of PHB. For CA and lignin, conclusions regarding their biodegradation can be drawn with lower resolutions. The proposed method is also able to quantify the biodegradation of blends or composite materials, which differentiates it from commonly used degradation detection methods.}, language = {en} }