@inproceedings{StaatHeitzer2002,
  author    = {Staat, Manfred and Heitzer, Michael},
  title     = {The restricted influence of kinematic hardening on shakedown loads},
  year      = {2002},
  abstract  = {Structural design analyses are conducted with the aim of verifying the exclusion of ratcheting. To this end it is important to make a clear distinction between the shakedown range and the ratcheting range. In cyclic plasticity more sophisticated hardening models have been suggested in order to model the strain evolution observed in ratcheting experiments. The hardening models used in shakedown analysis are comparatively simple. It is shown that shakedown analysis can make quite stable predictions of admissible load ranges despite the simplicity of the underlying hardening models. A linear and a nonlinear kinematic hardening model of two-surface plasticity are compared in material shakedown analysis. Both give identical or similar shakedown ranges. Structural shakedown analyses show that the loading may have a more pronounced effect than the hardening model.},
  subject      = {Biomedizinische Technik},
  language  = {en}
}
@inproceedings{KraftNagl2003,
  author    = {Kraft, Bodo and Nagl, Manfred},
  title     = {Support of Conceptual Design in Civil Engineering by Graph-based Tools},
  year      = {2003},
  abstract  = {WS GTaD-2003 - The 1st Workshop on Graph Transformations and Design ed Grabska, E., Seite 6-7, Jagiellonian University Krakow. 2 pages},
  subject      = {CAD},
  language  = {de}
}
@article{Kraft2003,
  author    = {Kraft, Bodo},
  title     = {Conceptual design mit ArchiCAD 8 : Forschungsprojekt an der RWTH Aachen},
  year      = {2003},
  abstract  = {Projektbericht in GraphisoftNews - Architektur und Bauen in einer vernetzten Welt 3/2003 4 Seiten},
  subject      = {CAD},
  language  = {de}
}
@misc{Kraft2003,
  author    = {Kraft, Bodo},
  title     = {LexiCAD Step by Step : B{\"u}rogeb{\"a}ude : Erstellen eines Grundrisses mit RoomObjects und LexiCAD},
  year      = {2003},
  abstract  = {11 Seiten, 22 Abbildungen 1. Konstruktion des Außenumrisses 2. Festlegung der inneren R{\"a}ume 3. Einf{\"u}gen der RoomLinks 4. Wallgenerator},
  subject      = {CAD},
  language  = {de}
}
@inproceedings{KraftNagl2003,
  author    = {Kraft, Bodo and Nagl, Manfred},
  title     = {Semantic tool support for conceptual design},
  year      = {2003},
  abstract  = {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.},
  subject      = {CAD},
  language  = {en}
}
@inproceedings{DigelTemizArtmannArtmannetal.2003,
  author    = {Digel, Ilya and Temiz Artmann, Ayseg{\"u}l and Artmann, Gerhard and Nojima, H.},
  title     = {Plasma cluster ions (PCI) influence on microbial cells viability : [abstract]},
  year      = {2003},
  abstract  = {Recently, SHARP corporation has developed the world's first "Plasma Cluster Ions (PCI)" air purification technology, which uses plasma discharge to generate cluster ions. The new plasma cluster device releases into the air positive and negative ions, which are harmless to humans and are able to decompose and deactivate airborne substances by chemical reactions. A lot of phenomenological tests of the PCI air purification technology on microbial cells have been conducted. And, in most cases, it has been shown that PCI demonstrate strongly pronounced killing effect. Although, the particular mechanisms of PCI action are still not evident. We studied variations in resistance to PCI among gram-positive airborne microorganisms, as well as some dose-dependent, spatial, cultural and biochemical properties of PCI action in respect of Staphylococcus spp, Enterococcus spp, Micrococcus spp.},
  subject      = {Clusterion},
  language  = {en}
}
@inproceedings{DigelTemizArtmannNojimaetal.2003,
  author    = {Digel, Ilya and Temiz Artmann, Ayseg{\"u}l and Nojima, H. and Artmann, Gerhard},
  title     = {Effects of plasma generated ions on bacteria : [poster]},
  year      = {2003},
  abstract  = {Summary and Conclusions PCIs were clearly effective in terms of their antibacterial effects with the strains tested. This efficacy increased with the time the bacteries were exposed to PCIs. The bactericidal action has proved to be irreversible. PCIs were significantly less effective in shadowed areas. PCI exposure caused multiple protein damages as observed in SDS PAGE studies. There was no single but multiple molecular mechanism causing the bacterial death.},
  subject      = {Clusterion},
  language  = {en}
}
@inproceedings{DigelTemizArtmannNojimaetal.2003,
  author    = {Digel, Ilya and Temiz Artmann, Ayseg{\"u}l and Nojima, H. and Artmann, Gerhard},
  title     = {Some peculiarities of application of cluster ions generated by plasma in respect of indoor air purification :[abstract]},
  year      = {2003},
  abstract  = {Recently, the SHARP Corporation, Japan, has developed the world's first "Plasma Cluster Ions (PCI)" air purification technology using plasma discharge to generate cluster ions. The new plasma cluster device releases positive and negative ions into the air, which are able to decompose and deactivate harmful airborne substances by chemical reactions. Because cluster ions consist of positive and negative ions that normally exist in the natural world, they are completely harmless and safe to humans. The amount of ozone generated by cluster ions is less than 0.01 ppm, which is significantly less than the 0.05-ppm standard for industrial operations and consumer electronics. This amount, thus, has no harming effects whatsoever on the human body. But particular properties and chemical processes in PCI treatment are still under study. It has been shown that PCI in most cases show strongly pronounced irreversible killing effects in respect of airborne microflora due to free-radical induced reactions and can be considered as a potent technology to disinfect both home, medical and industrial appliances.},
  subject      = {Clusterion},
  language  = {en}
}
@inproceedings{DigelTemizArtmannNojimaetal.2003,
  author    = {Digel, Ilya and Temiz Artmann, Ayseg{\"u}l and Nojima, H. and Artmann, Gerhard},
  title     = {Plasma-generated cluster ions' effects on indoor microflora : [abstract]},
  year      = {2003},
  abstract  = {Recently, SHARP corporation has developed the world's first "Plasma Cluster Ions® (PCI)" air purification technology, which uses plasma discharge to generate cluster ions. The new Plasma Cluster Device releases positive and negative ions into the air, which are harmless to humans and are able to decompose and deactivate airborne substances by chemical reactions. In the past, phenomenological tests on the efficacy of the PCI air purification technology on microbial cells have been conducted. In most cases, it has been shown that PCI demonstrated strongly pronounced killing effects on microorganisms. However, the particular mechanisms of PCI action still have to be uncovered.},
  subject      = {Clusterion},
  language  = {en}
}
@article{BaroudWuBohneretal.2003,
  author    = {Baroud, G. and Wu, J.Z. and Bohner, M and Sponagel, Stefan and Steffen, T.},
  title     = {How to determine the permeability for cement infiltration into osteoporotic cancellous bone},
  series = {Medical Engineering \& Physics. 25 (2003), H. 4},
  journal   = {Medical Engineering \& Physics. 25 (2003), H. 4},
  issn      = {1350-4533},
  pages     = {283 -- 288},
  year      = {2003},
  abstract  = {Cement augmentation is an emerging surgical procedure in which bone cement is used to infiltrate and reinforce osteoporotic vertebrae. Although this infiltration procedure has been widely applied, it is performed empirically and little is known about the flow characteristics of cement during the injection process. We present a theoretical and experimental approach to investigate the intertrabecular bone permeability during the infiltration procedure. The cement permeability was considered to be dependent on time, bone porosity, and cement viscosity in our analysis. In order to determine the time-dependent permeability, ten cancellous bone cores were harvested from osteoporotic vertebrae, infiltrated with acrylic cement at a constant flow rate, and the pressure drop across the cores during the infiltration was measured. The viscosity dependence of the permeability was determined based on published experimental data. The theoretical model for the permeability as a function of bone porosity and time was then fit to the testing data. Our findings suggest that the intertrabecular bone permeability depends strongly on time. For instance, the initial permeability (60.89 mm4/N.s) reduced to approximately 63\% of its original value within 18 seconds. This study is the first to analyze cement flow through osteoporotic bone. The theoretical and experimental models provided in this paper are generic. Thus, they can be used to systematically study and optimize the infiltration process for clinical practice.},
  subject      = {Osteoporose},
  language  = {en}
}
@article{Staat2003,
  author    = {Staat, Manfred},
  title     = {Shakedown and ratchetting under tension-torsion loadings: analysis and experiments},
  year      = {2003},
  abstract  = {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.},
  subject      = {Einspielen <Werkstoff>},
  language  = {en}
}
@inproceedings{Staat2003,
  author    = {Staat, Manfred},
  title     = {Design by Analysis of Pressure Components by non-linear Optimization},
  year      = {2003},
  abstract  = {This paper presents the direct route to Design by Analysis (DBA) of the new European pressure vessel standard in the language of limit and shakedown analysis (LISA). This approach leads to an optimization problem. Its solution with Finite Element Analysis is demonstrated for some examples from the DBA-Manual. One observation from the examples is, that the optimisation approach gives reliable and close lower bound solutions leading to simple and optimised design decision.},
  language  = {en}
}
@inproceedings{KraftNagl2004,
  author    = {Kraft, Bodo and Nagl, Manfred},
  title     = {Parameterized specification of conceptual design tools in civil engineering},
  year      = {2004},
  abstract  = {Applications of Graph Transformations with Industrial Relevance Lecture Notes in Computer Science, 2004, Volume 3062/2004, 90-105, DOI: 10.1007/978-3-540-25959-6_7 In this paper we discuss how tools for conceptual design in civil engineering can be developed using graph transformation specifications. These tools consist of three parts: (a) for elaborating specific conceptual knowledge (knowledge engineer), (b) for working out conceptual design results (architect), and (c) automatic consistency analyses which guarantee that design results are consistent with the underlying specific conceptual knowledge. For the realization of such tools we use a machinery based on graph transformations. In a traditional PROGRES tool specification the conceptual knowledge for a class of buildings is hard-wired within the specification. This is not appropriate for the experimentation platform approach we present in this paper, as objects and relations for conceptual knowledge are due to many changes, implied by evaluation of their use and corresponding improvements. Therefore, we introduce a parametric specification method with the following characteristics: (1) The underlying specific knowledge for a class of buildings is not fixed. Instead, it is built up as a data base by using the knowledge tools. (2) The specification for the architect tools also does not incorporate specific conceptual knowledge. (3) An incremental checker guarantees whether a design result is consistent with the current state of the underlying conceptual knowledge (data base).},
  subject      = {CAD},
  language  = {de}
}
@inproceedings{Kraft2004,
  author    = {Kraft, Bodo},
  title     = {Conceptual design tools for civil engineering},
  year      = {2004},
  abstract  = {Applications of Graph Transformations with Industrial Relevance Lecture Notes in Computer Science, 2004, Volume 3062/2004, 434-439, DOI: http://dx.doi.org/10.1007/978-3-540-25959-6_33 This paper gives a brief overview of the tools we have developed to support conceptual design in civil engineering. Based on the UPGRADE framework, two applications, one for the knowledge engineer and another for architects allow to store domain specific knowledge and to use this knowledge during conceptual design. Consistency analyses check the design against the defined knowledge and inform the architect if rules are violated.},
  subject      = {CAD},
  language  = {en}
}
@inproceedings{KraftWilhelms2004,
  author    = {Kraft, Bodo and Wilhelms, N.},
  title     = {Interactive distributed knowledge support for conceptual building design},
  isbn      = {3-86068-213-X},
  year      = {2004},
  abstract  = {In: Net-distributed Co-operation : Xth International Conference on Computing in Civil and Building Engineering, Weimar, June 02 - 04, 2004 ; proceedings / [ed. by Karl Beuke ...] . - Weimar: Bauhaus-Univ. Weimar 2004. - 1. Aufl. . Seite 1-14 ISBN 3-86068-213-X International Conference on Computing in Civil and Building Engineering <10, 2004, Weimar> Summary In our project, we develop new tools for the conceptual design phase. During conceptual design, the coarse functionality and organization of a building is more important than a detailed worked out construction. We identify two roles, first the knowledge engineer who is responsible for knowledge definition and maintenance; second the architect who elaborates the conceptual de-sign. The tool for the knowledge engineer is based on graph technology, it is specified using PROGRES and the UPGRADE framework. The tools for the architect are integrated to the in-dustrial CAD tool ArchiCAD. Consistency between knowledge and conceptual design is en-sured by the constraint checker, another extension to ArchiCAD.},
  subject      = {CAD},
  language  = {en}
}
@inproceedings{KirchhofKraft2004,
  author    = {Kirchhof, M. and Kraft, Bodo},
  title     = {UML-based modeling of architectural knowledge and design},
  year      = {2004},
  abstract  = {IASSE-2004 - 13th International Conference on Intelligent and Adaptive Systems and Software Engineering eds. W. Dosch, N. Debnath, pp. 245-250, ISCA, Cary, NC, 1-3 July 2004, Nice, France We introduce a UML-based model for conceptual design support in civil engineering. Therefore, we identify required extensions to standard UML. Class diagrams are used for elaborating building typespecific knowledge: Object diagrams, implicitly contained in the architect's sketch, are validated against the defined knowledge. To enable the use of industrial, domain-specific tools, we provide an integrated conceptual design extension. The developed tool support is based on graph rewriting. With our approach architects are enabled to deal with semantic objects during early design phase, assisted by incremental consistency checks.},
  subject      = {UML},
  language  = {en}
}
@techreport{NaglKraft2004,
  author    = {Nagl, Manfred and Kraft, Bodo},
  title     = {Graphbasierte Werkzeuge zur Unterst{\"u}tzung des konzeptuellen Geb{\"a}ude-Entwurfs : Bericht {\"u}ber den 2. F{\"o}rderzeitraum des Schwerpunktprogramms : DFG-Schwerpunktprogramm 1103 : Vernetzt-kooperative Planungsprozesse im Konstruktiven Ingenieurbau. - Auch unter dem Titel: Neue Software-Werkzeuge zur Unterst{\"u}tzung des konzeptuellen Geb{\"a}udeentwurfs},
  year      = {2004},
  abstract  = {Der konstruktive Entwurf wird in derzeitigen CAD-Systemen gut unterst{\"u}tzt, nicht aber der konzeptuelle Geb{\"a}ude-Entwurf. Dieser abstrahiert von konstruktiven Elementen wie Linie, Wand oder Decke, um auf die Konzepte, d.h. die eigentlichen Funktionen, heraus zu arbeiten. Diese abstraktere, funktionale Sichtweise auf ein Geb{\"a}ude ist w{\"a}hrend der fr{\"u}hen Entwurfsphase essentiell, um Struktur und Organisation des gesamten Geb{\"a}udes zu erfassen. Bereits in dieser Phase muss Fachwissen (z. B. rechtliche, {\"o}konomische und technische Bestimmungen) ber{\"u}cksichtigt werden. Im Rahmen des vorliegenden Projekts werden Software-Werkzeuge integriert in industrielle CAD-Systeme entwickelt, die den konzeptuellen Geb{\"a}ude-Entwurf erm{\"o}glichen und diesen gegen Fachwissen pr{\"u}fen. Das Projekt ist in zwei Teile gegliedert. Im Top-Down-Ansatz werden Datenstrukturen und Methoden zur Strukturierung, Repr{\"a}sentation und Evaluation von geb{\"a}udespezifischem Fachwissen erarbeitet. Dieser Teil baut auf den graphbasierten Werkzeugen PROGRES und UPGRADE des Lehrstuhls auf. Der Bottom-Up-Ansatz ist industriell orientiert und hat zum Ziel, das kommerzielle CAD-System ArchiCAD zu erweitern. Hierbei soll der fr{\"u}he, konzeptuelle Geb{\"a}ude-Entwurf in einem CAD-System erm{\"o}glicht werden. Der Entwurf kann dar{\"u}ber hinaus gegen das definierte Fachwissen gepr{\"u}ft werden. Im Rahmen des graphbasierten Top-Down-Ansatzes wurde zun{\"a}chst eine neue Spezifikationsmethode f{\"u}r die Sprache PROGRES entwickelt. Das PROGRES-System erlaubt die Spezifikation von Werkzeugen in deklarativer Form. {\"U}blicherweise wird dom{\"a}nenspezifisches Fachwissen in der PROGRES-Spezifikation codiert, das daraus generierte visuelle Werkzeug stellt dann die entsprechende Funktionalit{\"a}t zur Verf{\"u}gung. Mit dieser Methode sind am Lehrstuhl f{\"u}r Informatik III Werkzeuge f{\"u}r verschie-dene Anwendungsdom{\"a}nen entstanden. In unserem Fall versetzen wir einen Dom{\"a}nen-Experten, z. B. einen erfahrenen Architekten, in die Lage, Fachwissen zur Laufzeit einzugeben, dieses zu evaluieren, abzu{\"a}ndern oder zu erg{\"a}nzen. Im Rahmen der bisherigen Arbeit wurde dazu eine parametrisierte PROGRES-Spezifikation und zwei darauf aufbauende Werkzeuge entwickelt, welche die dynamische Eingabe von geb{\"a}ude-technisch relevantem Fachwissen erlauben und einen graphbasierten, konzeptuellen Geb{\"a}ude-Entwurf erm{\"o}glichen. In diesem konzeptuellen Geb{\"a}ude-Entwurf wird von Raumgr{\"o}ßen und Positionen abstrahiert, um die funktionale Struktur eines Geb{\"a}udes zu beschreiben. Das Fachwissen kann von einem Architekten visuell definiert werden. Es k{\"o}nnen semantische Einheiten, im einfachsten Fall R{\"a}ume, nach verschiedenen Kriterien kategorisiert und klassifiziert werden. Mit Hilfe von Attributen und Relationen k{\"o}nnen die semantischen Einheiten pr{\"a}ziser beschrieben und in Beziehung zueinander gesetzt werden. Die in PROGRES spezifizierten Konsistenz-Analysen erlauben die Pr{\"u}fung eines graphbasierten konzeptuellen Geb{\"a}ude-Entwurfs gegen das dynamisch eingef{\"u}gte Fachwissen. Im zweiten Teil des Forschungsprojekts, dem Bottom-Up-Ansatz, wird das CAD-System ArchiCAD erweitert, um den integrierten konzeptuellen Geb{\"a}ude-Entwurf zu erm{\"o}glichen. Der Architekt erh{\"a}lt dazu neue Entwurfselemente, die Raumobjekte, welche die relevanten semantischen Einheiten w{\"a}hrend der fr{\"u}hen Entwurfsphase repr{\"a}sentieren. Mit Hilfe der Raumobjekte kann der Architekt in ArchiCAD den Grundriss und das Raumprogramm eines Geb{\"a}udes entwerfen, ohne von konstruktiven Details in seiner Kreativit{\"a}t eingeschr{\"a}nkt zu werden. Die Arbeitsweise mit Raumobjekten entspricht dem informellen konzeptuellen Entwurf auf einer Papierskizze und ist daher f{\"u}r den Architekten intuitiv und einfach zu verwenden. Durch die Integration in ArchiCAD ergibt sich eine weitere Unterst{\"u}tzung: Das im Top-Down-Ansatz spezifizierte Fach-wissen wird verwendet, um den konzeptuellen Geb{\"a}ude-Entwurf des Architekten auf Regelverletzungen zu {\"u}berpr{\"u}fen. Entwurfsfehler werden angezeigt. Zum Abschluss des konzeptuellen Geb{\"a}ude-Entwurfs mit Raumobjekten wird durch ein weiteres neu entwickeltes Werkzeug eine initiale Wandstruktur automatisch erzeugt, die als Grundlage f{\"u}r die folgenden konstruktiven Entwurfsphasen dient. Alle beschriebenen Erwei-terungen sind in ArchiCAD integriert, sie sind f{\"u}r den Architekten daher leicht zu erlernen und einfach zu bedienen.},
  subject      = {CAD},
  language  = {de}
}
@inproceedings{DigelDemirciTrzewiketal.2004,
  author    = {Digel, Ilya and Demirci, Taylan and Trzewik, J{\"u}rgen and Linder, Peter and Temiz Artmann, Ayseg{\"u}l},
  title     = {Fibroblast response to mechanical stress: role of the adhesion substrate : [abstract]},
  year      = {2004},
  abstract  = {Mechanical stimulation of the cells resulted in evident changes in the cell morphology, protein composition and gene expression. Microscopically, additional formation of stress fibers accompanied by cell re-arrangements in a monolayer was observed. Also, significant activation of p53 gene was revealed as compared to control. Interestingly, the use of CellTech membrane coating induced cell death after mechanical stress had been applied. Such an effect was not detected when fibronectin had been used as an adhesion substrate.},
  subject      = {Fibroblast},
  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{VuStaat2004,
  author    = {Vu, Duc-Khoi and Staat, Manfred},
  title     = {An algorithm for shakedown analysis of structure with temperature dependent yield stress},
  year      = {2004},
  abstract  = {This work is an attempt to answer the question: How to use convex programming in shakedown analysis of structures made of materials with temperature-dependent properties. Based on recently established shakedown theorems and formulations, a dual relationship between upper and lower bounds of the shakedown limit load is found, an algorithmfor shakedown analysis is proposed. While the original problem is neither convex nor concave, the algorithm presented here has the advantage of employing convex programming tools.},
  subject      = {Einspielen <Werkstoff>},
  language  = {en}
}