TY - JOUR A1 - Staat, Manfred T1 - Shakedown and ratchetting under tension-torsion loadings: analysis and experiments N2 - Structural design analyses are conducted with the aim of verifying the exclusion of ratchetting. To this end it is important to make a clear distinction between the shakedown range and the ratchetting range. The performed experiment comprised a hollow tension specimen which was subjected to alternating axial forces, superimposed with constant moments. First, a series of uniaxial tests has been carried out in order to calibrate a bounded kinematic hardening rule. The load parameters have been selected on the basis of previous shakedown analyses with the PERMAS code using a kinematic hardening material model. It is shown that this shakedown analysis gives reasonable agreement between the experimental and the numerical results. A linear and a nonlinear kinematic hardening model of two-surface plasticity are compared in material shakedown analysis. KW - Einspielen KW - Einspielen KW - Ratchetting KW - Zug-Druck Belastung KW - shakedown KW - ratchetting KW - tension–torsion loading Y1 - 2003 ER - TY - CHAP A1 - Kraft, Bodo A1 - Nagl, Manfred T1 - Semantic tool support for conceptual design N2 - ITCE-2003 - 4th Joint Symposium on Information Technology in Civil Engineering ed Flood, I., Seite 1-12, ASCE (CD-ROM), Nashville, USA In this paper we discussed graph based tools to support architects during the conceptual design phase. Conceptual Design is defined before constructive design; the used concepts are more abstract. We develop two graph based approaches, a topdown using the graph rewriting system PROGRES and a more industrially oriented approach, where we extend the CAD system ArchiCAD. In both approaches, knowledge can be defined by a knowledge engineer, in the top-down approach in the domain model graph, in the bottom-up approach in the in an XML file. The defined knowledge is used to incrementally check the sketch and to inform the architect about violations of the defined knowledge. Our goal is to discover design error as soon as possible and to support the architect to design buildings with consideration of conceptual knowledge. KW - CAD KW - CAD KW - Bauingenieurwesen KW - CAD KW - civil engineering Y1 - 2003 ER - TY - CHAP A1 - Kraft, Bodo A1 - Schneider, Gerd T1 - Semantic Roomobjects for Conceptual Design Support : A Knowledge-based Approach N2 - In: Computer Aided Architectural Design Futures 2005 2005, Part 4, 207-216, DOI: http://dx.doi.org/10.1007/1-4020-3698-1_19 The conceptual design at the beginning of the building construction process is essential for the success of a building project. Even if some CAD tools allow elaborating conceptual sketches, they rather focus on the shape of the building elements and not on their functionality. We introduce semantic roomobjects and roomlinks, by way of example to the CAD tool ArchiCAD. These extensions provide a basis for specifying the organisation and functionality of a building and free architects being forced to directly produce detailed constructive sketches. Furthermore, we introduce consistency analyses of the conceptual sketch, based on an ontology containing conceptual relevant knowledge, specific to one class of buildings. KW - CAD KW - CAD KW - Bauingenieurwesen KW - CAD KW - civil engineering Y1 - 2005 SN - 978-1-4020-3460-2 ER - TY - CHAP A1 - Kraft, Bodo A1 - Retkowitz, Daniel T1 - Rule-Dependencies for Visual Knowledge Specification in Conceptual Design N2 - In: Proc. of the 11th Intl. Conf. on Computing in Civil and Building Engineering (ICCCBE-XI) ed. Hugues Rivard, Montreal, Canada, Seite 1-12, ACSE (CD-ROM), 2006 Currently, the conceptual design phase is not adequately supported by any CAD tool. Neither the support while elaborating conceptual sketches, nor the automatic proof of correctness with respect to effective restrictions is currently provided by any commercial tool. To enable domain experts to store the common as well as their personal domain knowledge, we develop a visual language for knowledge formalization. In this paper, a major extension to the already existing concepts is introduced. The possibility to define rule dependencies extends the expressiveness of the knowledge definition language and contributes to the usability of our approach. KW - CAD KW - CAD KW - Bauingenieurwesen KW - CAD KW - civil engineering Y1 - 2006 ER - TY - CHAP A1 - Kurulgan Demirci, Eylem A1 - Linder, Peter A1 - Demirci, Taylan A1 - Gierkowski, Jessica R. A1 - Digel, Ilya A1 - Gossmann, Matthias A1 - Temiz Artmann, Aysegül T1 - rhAPC reduces the endothelial cell permeability via a decrease of cellular mechanical contractile tensions : [abstract] N2 - In this study, the CellDrum technology quanitfying cellular mechanical tension on a pico-scale was used to investigate the effect of LPS (lipopolysaccharide) on HAoEC (Human Aortic Endothelial Cell) tension. KW - Endothelzelle KW - Sepsis KW - kontraktile Spannung KW - rhAPC KW - contractile tension KW - rhAPC KW - celldrum technology Y1 - 2010 ER - TY - CHAP A1 - Sakthivel, Mariappan A1 - Weppner, Werner T1 - Response behaviour of a hydrogen sensor based on ionic conducting polymer-metal interfaces prepared by the chemical reduction method N2 - A solid-state amperometric hydrogen sensor based on a protonated Nafion membrane and catalytic active electrode operating at room temperature was fabricated and tested. Ionic conducting polymer-metal electrode interfaces were prepared chemically by using the impregnation-reduction method. The polymer membrane was impregnated with tetra-ammine platinum chloride hydrate and the metal ions were subsequently reduced by using either sodium tetrahydroborate or potassium tetrahydroborate. The hydrogen sensing characteristics with air as reference gas is reported. The sensors were capable of detecting hydrogen concentrations from 10 ppm to 10% in nitrogen. The response time was in the range of 10-30 s and a stable linear current output was observed. The thin Pt films were characterized by XRD, Infrared Spectroscopy, Optical Microscopy, Atomic Force Microscopy, Scanning Electron Microscopy and EDAX. KW - Biosensor KW - Hydrogen sensor KW - amperometric sensor KW - porous Pt electrode KW - chemical reduction method Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1399 ER - TY - CHAP A1 - Burgazzi, L. A1 - Fiorini, F. A1 - De Magistris, W. (u.a.) A1 - Lensa, W. von A1 - Staat, Manfred A1 - Altes, J. T1 - Reliability Assessment of Passive Safety Systems T2 - Proceedings of the 6th International Conference on Nuclear Engineering : ICONE : May 10 - 14, 1998, San Diego, Calif. Y1 - 1998 N1 - CD-ROM PB - American Society of Mechanical Engineers CY - New York ER - TY - CHAP A1 - Tran, Thanh Ngoc A1 - Pham, Phu Tinh A1 - Staat, Manfred T1 - Reliability analysis of shells based on direct plasticity methods N2 - Abstracts der CD-Rom Proceedings of the 8th World Congress on Computational Mechanics (WCCM8) and 5th Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2008) 30.06. - 04.07.2008 Venedig, Italien. 2 Seiten Zusammenfassung der Autoren mit graph. Darst. und Literaturverzeichnis N2 - Abstracts of the Proceedings of the 8th World Congress on Computational Mechanics (WCCM8) and 5th Congress on Computational Methods in Applied Sciences and Engineering (ECCOMAS 2008) June 30th - July, 4th 2008, Venice, Italy. 2 pages with abstracts of the authors, Ill. and references. KW - Finite-Elemente-Methode KW - Limit analysis KW - Shakedown analysis KW - First-order reliability method KW - second-order reliability method KW - Sensitivity Y1 - 2008 ER - TY - JOUR A1 - Röthenbacher, Annika A1 - Cesari, Matteo A1 - Doppler, Christopher E.J. A1 - Okkels, Niels A1 - Willemsen, Nele A1 - Sembowski, Nora A1 - Seger, Aline A1 - Lindner, Marie A1 - Brune, Corinna A1 - Stefani, Ambra A1 - Högl, Birgit A1 - Bialonski, Stephan A1 - Borghammer, Per A1 - Fink, Gereon R. A1 - Schober, Martin A1 - Sommerauer, Michael T1 - RBDtector: an open-source software to detect REM sleep without atonia according to visual scoring criteria JF - Scientific Reports N2 - REM sleep without atonia (RSWA) is a key feature for the diagnosis of rapid eye movement (REM) sleep behaviour disorder (RBD). We introduce RBDtector, a novel open-source software to score RSWA according to established SINBAR visual scoring criteria. We assessed muscle activity of the mentalis, flexor digitorum superficialis (FDS), and anterior tibialis (AT) muscles. RSWA was scored manually as tonic, phasic, and any activity by human scorers as well as using RBDtector in 20 subjects. Subsequently, 174 subjects (72 without RBD and 102 with RBD) were analysed with RBDtector to show the algorithm’s applicability. We additionally compared RBDtector estimates to a previously published dataset. RBDtector showed robust conformity with human scorings. The highest congruency was achieved for phasic and any activity of the FDS. Combining mentalis any and FDS any, RBDtector identified RBD subjects with 100% specificity and 96% sensitivity applying a cut-off of 20.6%. Comparable performance was obtained without manual artefact removal. RBD subjects also showed muscle bouts of higher amplitude and longer duration. RBDtector provides estimates of tonic, phasic, and any activity comparable to human scorings. RBDtector, which is freely available, can help identify RBD subjects and provides reliable RSWA metrics. Y1 - 2022 U6 - https://doi.org/10.1038/s41598-022-25163-9 SN - 2045-2322 VL - 12 IS - Article number: 20886 SP - 1 EP - 14 PB - Springer Nature CY - London ER - TY - CHAP A1 - Mirmohseni, Abdolreza A1 - Rostamizadeh, Kobra T1 - Quartz crystal nanobalance in conjunction with principal component analysis for identification of volatile organic compounds N2 - Quartz crystal nanobalance (QCN) sensors are considered as powerful masssensitive sensors to determine materials in the sub-nanogram level. In this study, a single piezoelectric quartz crystal nanobalance modified with polystyrene was employed to detect benzene, toluene, ethylbenzene and xylene (BTEX compounds). The frequency shift of the QCN sensor was found to be linear against the BTEX compound concentrations in the range about 1-45 mg l-1. The correlation coefficients for benzene, toluene, ethylbenzene, and xylene were 0.991, 0.9977, 0.9946 and 0.9971, respectively. The principal component analysis was also utilized to process the frequency response data of the single piezoelectric crystal at different times, considering to the different adsorption-desorption dynamics of BTEX compounds. Using principal component analysis, it was found that over 90% of the data variance could still be explained by use of two principal components (PC1 and PC2). Subsequently, the successful identification of benzene and toluene was possible through the principal component analysis of the transient responses of the polystyrene modified QCN sensor. The results showed that the polystyrene-modified QCN had favorable identification and quantification performances for the BTEX compounds. KW - Biosensor KW - Quartz crystal nanobalance (QCN) KW - BTEX compounds KW - principal component Y1 - 2006 U6 - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1434 ER -