TY  - CHAP
A1  - Staat, Manfred
A1  - Heitzer, Michael
A1  - Hicken, E. F.
T1  - LISA - ein europäisches Projekt zur FEM-basierten Traglast- und Einspielanalyse
T1  - LISA - a European project for FEM-based limit and shakedown analysis
N2  - Traglast- und Einspielanalysen sind vereinfachte doch exakte Verfahren der Plastizität, die neben ausreichender Verformbarkeit keine einschränkenden Voraussetzungen beinhalten. Die Vereinfachungen betreffen die Beschaffung der Daten und Modelle für Details der Lastgeschichte und des Stoffverhaltens. Anders als die klassische Behandlung nichtlinearer Probleme der Strukturmechanik führt die Methode auf Optimierungsprobleme. Diese sind bei realistischen FEM-Modellen sehr groß. Das hat die industrielle Anwendung der Traglast- und Einspielanalysen stark verzögert. Diese Situation wird durch das Brite-EuRam Projekt LISA grundlegend geändert. In LISA entsteht auf der Basis des industriellen FEM-Programms PERMAS ein Verfahren zur direkten Berechnung der Tragfähigkeit duktiler Strukturen. Damit kann der Betriebsbereich von Komponenten und Bauwerken auf den plastischen Bereich erweitert werden, ohne den Aufwand gegenüber elastischen Analysen wesentlich zu erhöhen. Die beachtlichen Rechenzeitgewinne erlauben Parameterstudien und die Berechnung von Interaktionsdiagrammen, die einen schnellen Überblick über mögliche Betriebsbereiche vermitteln. Es zeigt sich, daß abhängig von der Komponente und ihren Belastungen teilweise entscheidende Sicherheitsgewinne zur Erweiterung der Betriebsbereiche erzielt werden können. Das Vorgehen erfordert vom Anwender oft ein gewisses Umdenken. Es werden keine Spannungen berechnet, um damit Sicherheit und Lebensdauer zu interpretieren. Statt dessen berechnet man direkt die gesuchte Sicherheit. Der Post-Prozessor wird nur noch zur Modell- und Rechenkontrolle benötigt. Das Vorgehen ist ähnlich der Stabilitätsanalyse (Knicken, Beulen). Durch namhafte industrielle Projektpartner werden Validierung und die Anwendbarkeit auf eine breite Palette technischer Probleme garantiert. Die ebenfalls in LISA entwickelten Zuverlässigkeitsanalysen sind nichlinear erst auf der Basis direkter Verfahren effektiv möglich. Ohne Traglast- und Einspielanalyse ist plastische Strukturoptimierung auch heute kaum durchführbar. Auf die vorgesehenen Erweiterungen der Werkstoffmodellierung für nichtlineare Verfestigung und für Schädigung konnte hier nicht eingegangen werden. Es herrscht ein deutlicher Mangel an Experimenten zum Nachweis der Grenzen zwischen elastischem Einspielen und dem Versagen durch LCF oder durch Ratchetting.
KW  - Einspielen <Werkstoff>
KW  - Traglast
KW  - Finite-Elemente-Methode
KW  - LISA
KW  - limit analysis
KW  - shakedown analysis
Y1  - 1999
ER  - 
TY  - CHAP
A1  - Heitzer, M.
A1  - Staat, Manfred
T1  - Direct FEM approach to design-by-analysis of pressurized components
N2  - Abstracts of the ACHEMA 2000 - International Meeting on Chemical Engineering, Environmental Protection and Biotechnology, May 22 - 27, 2000. Frankfurt am Main. Achema 2000 : special edition / Linde. [Ed.: Linde AG. Red.: Volker R. Leski]. - Wiesbaden : Linde AG, 2000. - 56 p. : Ill., . - pp: 79 - 81
N2  - Abstracts der ACHEMA 2000 - International Meeting on Chemical Engineering, Environmental Protection and Biotechnology, May 22 - 27, 2000. Frankfurt am Main.
KW  - Finite-Elemente-Methode
KW  - Finite-Elemente-Methode
KW  - limit analysis
KW  - shakedown analysis
Y1  - 2000
ER  - 
TY  - CHAP
A1  - Staat, Manfred
A1  - Heitzer, Michael
T1  - Direct static FEM approach to limit and shakedown analysis
N2  - Safety and reliability of structures may be assessed indirectly by stress distributions. Limit and shakedown theorems are simplified but exact methods of plasticity that provide safety factors directly in the loading space. These theorems may be used for a direct definition of the limit state function for failure by plastic collapse or by inadaptation. In a FEM formulation the limit state function is obtained from a nonlinear optimization problem. This direct approach reduces considerably the necessary knowledge of uncertain technological input data, the computing time, and the numerical error. Moreover, the direct way leads to highly effective and precise reliability analyses. The theorems are implemented into a general purpose FEM program in a way capable of large-scale analysis.
KW  - Einspielen <Werkstoff>
KW  - Nichtlineare Optimierung
KW  - Shakedown
KW  - Shakedown
KW  - limit load
KW  - lower bound theorem
KW  - nonlinear optimization
KW  - reliability
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Staat, Manfred
T1  - Basis Reduction for the Shakedown Problem for Bounded Kinematic Hardening Material
N2  - Limit and shakedown analysis are effective methods for assessing the load carrying capacity of a given structure. The elasto–plastic behavior of the structure subjected to loads varying in a given load domain is characterized by the shakedown load factor, defined as the maximum factor which satisfies the sufficient conditions stated in the corresponding static shakedown theorem. The finite element dicretization of the problem may lead to very large convex optimization. For the effective solution a basis reduction method has been developed that makes use of the special problem structure for perfectly plastic material. The paper proposes a modified basis reduction method for direct application to the two-surface plasticity model of bounded kinematic hardening material. The considered numerical examples show an enlargement of the load carrying capacity due to bounded hardening.
KW  - Finite-Elemente-Methode
KW  - Einspielen <Werkstoff>
KW  - Basis Reduktion
KW  - konvexe Optimierung
KW  - FEM
KW  - Druckgeräte
KW  - Basis reduction
KW  - Convex optimization
KW  - FEM
KW  - Shakedown analysis
Y1  - 2000
ER  - 
TY  - JOUR
A1  - Staat, Manfred
T1  - Direct FEM Limit and Shakedown Analysis with Uncertain Data
N2  - The structural reliability with respect to plastic collapse or to inadaptation is formulated on the basis of the lower bound limit and shakedown theorems. A direct definition of the limit state function is achieved which permits the use of the highly effective first order reliability methods (FORM) is achieved. The theorems are implemented into a general purpose FEM program in a way capable of large-scale analysis. The limit state function and its gradient are obtained from a mathematical optimization problem. This direct approach reduces considerably the necessary knowledge of uncertain technological input data, the computing time, and the numerical error, leading to highly effective and precise reliability analyses.
KW  - Finite-Elemente-Methode
KW  - Einspielen <Werkstoff>
KW  - FEM
KW  - Einspielanalyse
KW  - shakedown
KW  - limit load
KW  - reliability analysis
KW  - FEM
KW  - direct method
Y1  - 2000
ER  - 
TY  - CHAP
A1  - Staat, Manfred
A1  - Szelinski, E.
A1  - Heitzer, Michael
T1  - Kollapsanalyse von längsfehlerbehafteten Rohren und Behältern
T1  - Collapse analysis of longitudinally flawed pipes and vessels
N2  - Es werden verbesserte Kollapsanalysen von dickwandigen, mit axialen Oberflächenfehlern behafteten Rohren und Behältern vorgeschlagen.
KW  - Druckbehälter
KW  - Stahl
KW  - Druckbelastung
KW  - Druckbeanspruchung
KW  - Rohr
KW  - Rohrbruch
KW  - Fehlerstellen
KW  - pipes
KW  - vessels
KW  - load limit
KW  - burst tests
KW  - burst pressure
KW  - flaw
Y1  - 2001
ER  - 
TY  - CHAP
A1  - Staat, Manfred
A1  - Heitzer, Michael
A1  - Reinders, H.
A1  - Schubert, F.
T1  - Einspielen und Ratchetting bei Zug- und Torsionsbelastung: Analyse und Experimente
T1  - Shakedown and ratchetting under tension-torsion loadings: analysis and experiments
N2  - Traglast- und Einspielanalysen sind vereinfachte doch exakte Verfahren der klassischen Plastizitätstheorie, die neben ausreichender Verformbarkeit keine einschränkenden Voraussetzungen beinhalten. Die Vereinfachungen betreffen die Beschaffung der Daten und Modelle für Details der Lastgeschichte und des Stoffverhaltens. Eine FEM-basierte Traglast- und Einspielanalyse für ideal plastisches Material wurde auf ein kinematisch verfestigendes Materialgesetz erweitert und in das Finite Element Programm PERMAS implementiert. In einem einfachen Zug-Torsionsexperiment wurde eine Hohlprobe mit konstanter Torsion und zyklischer Zugbelastung beansprucht, um die neue Implementierung zu verifizieren. Es konnte gezeigt werden, dass die Einspielanalyse gut mit den experimentellen Ergebnissen übereinstimmt. Bei Verfestigung lassen sich wesentlich größere Sicherheiten nachweisen. Dieses Potential bedarf weiterer experimenteller Absicherung. Parallel dazu ist die Eisnpieltheorie auf fortschrittliche Verfestigungsansätze zu erweitern.
KW  - Zug-Druck-Beanspruchung
KW  - Einspielen <Werkstoff>
KW  - Ratcheting
KW  - Torsion
KW  - Zug-Druck-Belastung
KW  - Torsionsbelastung
KW  - shakedown
KW  - ratchetting
KW  - tension–torsion loading
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Staat, Manfred
T1  - Cyclic plastic deformation tests to verify FEM-based shakedown analyses
N2  - Fatigue analyses are conducted with the aim of verifying that thermal ratcheting is limited. To this end it is important to make a clear distintion between the shakedown range and the ratcheting range (continuing deformation). As part of an EU-supported research project, experiments were carried out using a 4-bar model. The experiment comprised a water-cooled internal tube, and three insulated heatable outer test bars. The system was subjected to alternating axial forces, superimposed with alternating temperatures at the outer bars. The test parameters were partly selected on the basis of previous shakedown analyses. During the test, temperatures and strains were measured as a function of time. The loads and the resulting stresses were confirmed on an ongoing basis during performance of the test, and after it. Different material models were applied for this incremental elasto-plastic analysis using the ANSYS program. The results of the simulation are used to verify the FEM-based shakedown analysis.
KW  - Materialermüdung
KW  - Einspielen <Werkstoff>
KW  - Materialermüdung
KW  - shakedown analyses
KW  - thermal ratcheting
KW  - fatigue analyses
Y1  - 2001
ER  - 
TY  - JOUR
A1  - Staat, Manfred
T1  - LISA - a European project for FEM-based limit and shakedown analysis
N2  - The load-carrying capacity or the safety against plastic limit states are the central questions in the design of structures and passive components in the apparatus engineering. A precise answer is most simply given by limit and shakedown analysis. These methods can be based on static and kinematic theorems for lower and upper bound analysis. Both may be formulated as optimization problems for finite element discretizations of structures. The problems of large-scale analysis and the extension towards realistic material modelling will be solved in a European research project. Limit and shakedown analyses are briefly demonstrated with illustrative examples.
KW  - Einspielen <Werkstoff>
KW  - Traglast
KW  - Finite-Elemente-Methode
KW  - Traglastanalyse
KW  - Einspielanalyse
KW  - FEM
KW  - limit analysis
KW  - shakedown analysis
Y1  - 2001
ER  - 
TY  - CHAP
A1  - Kraft, Bodo
A1  - Meyer, Oliver
A1  - Nagl, Manfred
T1  - Graph technology support for conceptual design in civil engineering
N2  - In: Advances in intelligent computing in engineering : proceedings of the 9.International EG-ICE Workshop ; Darmstadt, (01 - 03 August) 2002 / Martina Schnellenbach-Held ... (eds.) . - Düsseldorf: VDI-Verl., 2002 .- Fortschritt-Berichte VDI, Reihe 4, Bauingenieurwesen ; 180 ; S. 1-35 The paper describes a novel way to support conceptual design in civil engineering. The designer uses semantical tools guaranteeing certain internal structures of the design result but also the fulfillment of various constraints. Two different approaches and corresponding tools are discussed: (a) Visually specified tools with automatic code generation to determine a design structure as well as fixing various constraints a design has to obey. These tools are also valuable for design knowledge specialist. (b) Extensions of existing CAD tools to provide semantical knowledge to be used by an architect. It is sketched how these different tools can be combined in the future. The main part of the paper discusses the concepts and realization of two prototypes following the two above approaches. The paper especially discusses that specific graphs and the specification of their structure are useful for both tool realization projects.
KW  - CAD
KW  - CAD ;
KW  - CAD
KW  - civil engineering
Y1  - 2002
SN  - 3-18-318004-9
ER  - 
TY  - CHAP
A1  - Staat, Manfred
A1  - Heitzer, Michael
T1  - The restricted influence of kinematic hardening on shakedown loads
N2  - 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.
KW  - Biomedizinische Technik
KW  - Einspielen <Werkstoff>
KW  - Shakedown
KW  - Ratcheting
KW  - Bruchmechanik
KW  - shakedown
KW  - material shakedown
KW  - linear kinematic hardening
KW  - nonlinear kinematic hardening
KW  - ratchetting
Y1  - 2002
ER  - 
TY  - CHAP
A1  - Kraft, Bodo
A1  - Nagl, Manfred
T1  - Support of Conceptual Design in Civil Engineering by Graph-based Tools
N2  - WS GTaD-2003 - The 1st Workshop on Graph Transformations and Design ed Grabska, E., Seite 6-7, Jagiellonian University Krakow. 2 pages
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Kraft, Bodo
T1  - Conceptual design mit ArchiCAD 8 : Forschungsprojekt an der RWTH Aachen
N2  - Projektbericht in GraphisoftNews - Architektur und Bauen in einer vernetzten Welt 3/2003 4 Seiten
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - Architektur
KW  - CAD
KW  - civil engineering
KW  - architecture
Y1  - 2003
ER  - 
TY  - GEN
A1  - Kraft, Bodo
T1  - LexiCAD Step by Step : Bürogebäude : Erstellen eines Grundrisses mit RoomObjects und LexiCAD
N2  - 11 Seiten, 22 Abbildungen 1. Konstruktion des Außenumrisses 2. Festlegung der inneren Räume 3. Einfügen der RoomLinks 4. Wallgenerator
KW  - CAD
KW  - CAD
KW  - Architektur
KW  - CAD
KW  - architecture
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  - Digel, Ilya
A1  - Temiz Artmann, Aysegül
A1  - Artmann, Gerhard
A1  - Nojima, H.
T1  - Plasma cluster ions (PCI) influence on microbial cells viability : [abstract]
N2  - 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.
KW  - Clusterion
KW  - Raumluft
KW  - Luftreiniger
KW  - Plasmacluster ion technology
KW  - Air purification
Y1  - 2003
ER  - 
TY  - CHAP
A1  - Digel, Ilya
A1  - Temiz Artmann, Aysegül
A1  - Nojima, H.
A1  - Artmann, Gerhard
T1  - Effects of plasma generated ions on bacteria : [poster]
N2  - 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.
KW  - Clusterion
KW  - Bakterien
KW  - plasma generated ions
Y1  - 2003
ER  - 
TY  - CHAP
A1  - Digel, Ilya
A1  - Temiz Artmann, Aysegül
A1  - Nojima, H.
A1  - Artmann, Gerhard
T1  - Some peculiarities of application of cluster ions generated by plasma in respect of indoor air purification :[abstract]
N2  - 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.
KW  - Clusterion
KW  - Raumluft
KW  - Luftreiniger
KW  - Plasmacluster ion technology
KW  - Air purification
Y1  - 2003
ER  - 
TY  - CHAP
A1  - Digel, Ilya
A1  - Temiz Artmann, Aysegül
A1  - Nojima, H.
A1  - Artmann, Gerhard
T1  - Plasma-generated cluster ions' effects on indoor microflora : [abstract]
N2  - 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.
KW  - Clusterion
KW  - Raumluft
KW  - Luftreiniger
KW  - Plasmacluster ion technology
KW  - Air purification
Y1  - 2003
ER  - 
TY  - JOUR
A1  - Baroud, G.
A1  - Wu, J.Z.
A1  - Bohner, M
A1  - Sponagel, Stefan
A1  - Steffen, T.
T1  - How to determine the permeability for cement infiltration into osteoporotic cancellous bone
JF  - Medical Engineering & Physics. 25 (2003), H. 4
N2  - 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.
KW  - Osteoporose
KW  - Permeabilität
KW  - Viskose Strömung
KW  - Viskosität
KW  - Vertebroplastie
KW  - Cement infiltration
KW  - Vertebroplasty
KW  - Osteoporosis
KW  - Permeability
KW  - Experiment
KW  - Analysis
KW  - Viscous flow
Y1  - 2003
SN  - 1350-4533
SP  - 283
EP  - 288
ER  - 
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 <Werkstoff>
KW  - Einspielen
KW  - Ratchetting
KW  - Zug-Druck Belastung
KW  - shakedown
KW  - ratchetting
KW  - tension–torsion loading
Y1  - 2003
ER  - 
TY  - CHAP
A1  - Staat, Manfred
T1  - Design by Analysis of Pressure Components by non-linear Optimization
N2  - 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.
KW  - Analytischer Zulaessigkeitsnachweis
KW  - FEM
KW  - Einspiel-Analyse
KW  - design-by-analysis
KW  - finite element analysis
KW  - limit and shakedown analysis
Y1  - 2003
ER  - 
TY  - CHAP
A1  - Kraft, Bodo
A1  - Nagl, Manfred
T1  - Parameterized specification of conceptual design tools in civil engineering
N2  - 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).
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2004
ER  - 
TY  - CHAP
A1  - Kraft, Bodo
T1  - Conceptual design tools for civil engineering
N2  - 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.
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2004
ER  - 
TY  - CHAP
A1  - Kraft, Bodo
A1  - Wilhelms, N.
T1  - Interactive distributed knowledge support for conceptual building design
N2  - 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.
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2004
SN  - 3-86068-213-X
ER  - 
TY  - CHAP
A1  - Kirchhof, M.
A1  - Kraft, Bodo
T1  - UML-based modeling of architectural knowledge and design
N2  - 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.
KW  - UML
KW  - UML
KW  - Unified Modeling Language
KW  - UML
KW  - Unified Modeling Language
Y1  - 2004
ER  - 
TY  - RPRT
A1  - Nagl, Manfred
A1  - Kraft, Bodo
T1  - Graphbasierte Werkzeuge zur Unterstützung des konzeptuellen Gebäude-Entwurfs : Bericht über den 2. Förderzeitraum des Schwerpunktprogramms : DFG-Schwerpunktprogramm 1103 : Vernetzt-kooperative Planungsprozesse im Konstruktiven Ingenieurbau. - Auch unter dem Titel: Neue Software-Werkzeuge zur Unterstützung des konzeptuellen Gebäudeentwurfs
N2  - Der konstruktive Entwurf wird in derzeitigen CAD-Systemen gut unterstützt, nicht aber der konzeptuelle Gebäude-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 Gebäude ist während der frühen Entwurfsphase essentiell, um Struktur und Organisation des gesamten Gebäudes zu erfassen. Bereits in dieser Phase muss Fachwissen (z. B. rechtliche, ökonomische und technische Bestimmungen) berücksichtigt werden. Im Rahmen des vorliegenden Projekts werden Software-Werkzeuge integriert in industrielle CAD-Systeme entwickelt, die den konzeptuellen Gebäude-Entwurf ermöglichen und diesen gegen Fachwissen prüfen. Das Projekt ist in zwei Teile gegliedert. Im Top-Down-Ansatz werden Datenstrukturen und Methoden zur Strukturierung, Repräsentation und Evaluation von gebäudespezifischem 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 frühe, konzeptuelle Gebäude-Entwurf in einem CAD-System ermöglicht werden. Der Entwurf kann darüber hinaus gegen das definierte Fachwissen geprüft werden. Im Rahmen des graphbasierten Top-Down-Ansatzes wurde zunächst eine neue Spezifikationsmethode für die Sprache PROGRES entwickelt. Das PROGRES-System erlaubt die Spezifikation von Werkzeugen in deklarativer Form. Üblicherweise wird domänenspezifisches Fachwissen in der PROGRES-Spezifikation codiert, das daraus generierte visuelle Werkzeug stellt dann die entsprechende Funktionalität zur Verfügung. Mit dieser Methode sind am Lehrstuhl für Informatik III Werkzeuge für verschie-dene Anwendungsdomänen entstanden. In unserem Fall versetzen wir einen Domänen-Experten, z. B. einen erfahrenen Architekten, in die Lage, Fachwissen zur Laufzeit einzugeben, dieses zu evaluieren, abzuändern oder zu ergänzen. Im Rahmen der bisherigen Arbeit wurde dazu eine parametrisierte PROGRES-Spezifikation und zwei darauf aufbauende Werkzeuge entwickelt, welche die dynamische Eingabe von gebäude-technisch relevantem Fachwissen erlauben und einen graphbasierten, konzeptuellen Gebäude-Entwurf ermöglichen. In diesem konzeptuellen Gebäude-Entwurf wird von Raumgrößen und Positionen abstrahiert, um die funktionale Struktur eines Gebäudes zu beschreiben. Das Fachwissen kann von einem Architekten visuell definiert werden. Es können semantische Einheiten, im einfachsten Fall Räume, nach verschiedenen Kriterien kategorisiert und klassifiziert werden. Mit Hilfe von Attributen und Relationen können die semantischen Einheiten präziser beschrieben und in Beziehung zueinander gesetzt werden. Die in PROGRES spezifizierten Konsistenz-Analysen erlauben die Prüfung eines graphbasierten konzeptuellen Gebäude-Entwurfs gegen das dynamisch eingefügte Fachwissen. Im zweiten Teil des Forschungsprojekts, dem Bottom-Up-Ansatz, wird das CAD-System ArchiCAD erweitert, um den integrierten konzeptuellen Gebäude-Entwurf zu ermöglichen. Der Architekt erhält dazu neue Entwurfselemente, die Raumobjekte, welche die relevanten semantischen Einheiten während der frühen Entwurfsphase repräsentieren. Mit Hilfe der Raumobjekte kann der Architekt in ArchiCAD den Grundriss und das Raumprogramm eines Gebäudes entwerfen, ohne von konstruktiven Details in seiner Kreativität eingeschränkt zu werden. Die Arbeitsweise mit Raumobjekten entspricht dem informellen konzeptuellen Entwurf auf einer Papierskizze und ist daher für den Architekten intuitiv und einfach zu verwenden. Durch die Integration in ArchiCAD ergibt sich eine weitere Unterstützung: Das im Top-Down-Ansatz spezifizierte Fach-wissen wird verwendet, um den konzeptuellen Gebäude-Entwurf des Architekten auf Regelverletzungen zu überprüfen. Entwurfsfehler werden angezeigt. Zum Abschluss des konzeptuellen Gebäude-Entwurfs mit Raumobjekten wird durch ein weiteres neu entwickeltes Werkzeug eine initiale Wandstruktur automatisch erzeugt, die als Grundlage für die folgenden konstruktiven Entwurfsphasen dient. Alle beschriebenen Erwei-terungen sind in ArchiCAD integriert, sie sind für den Architekten daher leicht zu erlernen und einfach zu bedienen.
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2004
ER  - 
TY  - CHAP
A1  - Digel, Ilya
A1  - Demirci, Taylan
A1  - Trzewik, Jürgen
A1  - Linder, Peter
A1  - Temiz Artmann, Aysegül
T1  - Fibroblast response to mechanical stress: role of the adhesion substrate : [abstract]
N2  - 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.
KW  - Fibroblast
KW  - Mechanische Beanspruchung
KW  - celldrum technology
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Staat, Manfred
T1  - Plastic collapse analysis of longitudinally flawed pipes and vessels
N2  - 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.
KW  - Druckbehälter
KW  - Stahl
KW  - Druckbelastung
KW  - Druckbeanspruchung
KW  - Rohr
KW  - Rohrbruch
KW  - Druckbehälter
KW  - Stahl
KW  - Druckbelastung
KW  - Druckbeanspruchung
KW  - Rohrbruch
KW  - Fehlerstellen
KW  - pipes
KW  - vessels
KW  - load limit
KW  - burst tests
KW  - burst pressure
KW  - flaw
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Vu, Duc-Khoi
A1  - Staat, Manfred
T1  - An algorithm for shakedown analysis of structure with temperature dependent yield stress
N2  - 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.
KW  - Einspielen <Werkstoff>
KW  - Temperaturabhängigkeit
KW  - Fließgrenze
KW  - Shakedown
KW  - shakedown analysis
KW  - yield stress
Y1  - 2004
ER  - 
TY  - JOUR
A1  - Kühn, Raoul-Roman
A1  - Haugner, Werner
A1  - Staat, Manfred
A1  - Sponagel, Stefan
T1  - A Two Phase Mixture Model based on Bone Observation
N2  - An optimization method is developed to describe the mechanical behaviour of the human cancellous bone. The method is based on a mixture theory. A careful observation of the behaviour of the bone material leads to the hypothesis that the bone density is controlled by the principal stress trajectories (Wolff’s law). The basic idea of the developed method is the coupling of a scalar value via an eigenvalue problem to the principal stress trajectories. On the one hand this theory will permit a prediction of the reaction of the biological bone structure after the implantation of a prosthesis, on the other hand it may be useful in engineering optimization problems. An analytical example shows its efficiency.
KW  - Knochen
KW  - Knochenbildung
KW  - Knochenchirugie
KW  - Strukturanalyse
KW  - Schwammknochen
KW  - Knochendichte
KW  - Wolffsches Gesetz
KW  - bone structure
KW  - bone density
KW  - Wolff's Law
KW  - cancellous bone
Y1  - 2004
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  - Wilhelms, Nils
T1  - Visual Knowledge Specification for Conceptual Design
N2  - Proc. of the 2005 ASCE Intl. Conf. on Computing in Civil Engineering (ICCC 2005) eds. L. Soibelman und F. Pena-Mora, Seite 1-14, ASCE (CD-ROM), Cancun, Mexico, 2005 Current CAD tools are not able to support the fundamental conceptual design phase, and none of them provides consistency analyses of sketches produced by architects. To give architects a greater support at the conceptual design phase, we develop a CAD tool for conceptual design and a knowledge specification tool allowing the definition of conceptually relevant knowledge. The knowledge is specific to one class of buildings and can be reused. Based on a dynamic knowledge model, different types of design rules formalize the knowledge in a graph-based realization. An expressive visual language provides a user-friendly, human readable representation. Finally, consistency analyses enable conceptual designs to be checked against this defined knowledge. In this paper we concentrate on the knowledge specification part of our project.
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2005
ER  - 
TY  - CHAP
A1  - Kraft, Bodo
A1  - Retkowitz, Daniel
T1  - Operationale Semantikdefinition für konzeptuelles Regelwissen
N2  - In: Forum Bauinformatik 2005 : junge Wissenschaftler forschen / [Lehrstuhl Bauinformatik, Brandenburgische Technische Universität Cottbus. Frank Schley ... (Hrsg.)]. - Cottbus : Techn. Universität 2005. S. 1-10 ISBN 3-934934-11-0 
Mittels eines operationalen Ansatzes zur Semantikdefinition wird am Bei-spiel des konzeptuellen Gebäudeentwurfs ein Regelsystem formalisiert. Dazu werdenzwei Teile, zum einen das Regelwissen, zum anderen ein konzeptueller Entwurfsplan zunächst informell eingeführt und dann formal beschrieben. Darauf aufbauend wird die Grundlage für eine Konsistenzprüfung des konzeptuellen Entwurfs gegen das Regel-wissen formal angeben
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Staat, Manfred
T1  - Local and global collapse pressure of longitudinally flawed pipes and cylindrical vessels
N2  - 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.
KW  - Finite-Elemente-Methode
KW  - Grenzwertberechnung
KW  - Axialbelastung
KW  - FEM
KW  - Grenzwertberechnung
KW  - Axialbelastung
KW  - Traglastanalyse
KW  - Limit analysis
KW  - Global and local collapse
KW  - Axially cracked pipe
KW  - Pressure loaded crack-face
Y1  - 2005
ER  - 
TY  - JOUR
A1  - Staat, Manfred
T1  - Direct finite element route for design-by-analysis of pressure components
N2  - In the new European standard for unfired pressure vessels, EN 13445-3, there are two approaches for carrying out a Design-by-Analysis that cover both the stress categorization method (Annex C) and the direct route method (Annex B) for a check against global plastic deformation and against progressive plastic deformation. This paper presents the direct route in the language of limit and shakedown analysis. This approach leads to an optimization problem. Its solution with Finite Element Analysis is demonstrated for mechanical and thermal actions. One observation from the examples is that the so-called 3f (3Sm) criterion fails to be a reliable check against progressive plastic deformation. Precise conditions are given, which greatly restrict the applicability of the 3f criterion.
KW  - Einspielen <Werkstoff>
KW  - Plastizität
KW  - Deformation
KW  - Analytischer Zulaessigkeitsnachweis
KW  - Einspiel-Analyse
KW  - fortschreitende plastische Deformation
KW  - alternierend Verformbarkeit
KW  - Einspiel-Kriterium
KW  - Design-by-analysis
KW  - Shakedown analysis
KW  - Progressive plastic deformation
KW  - Alternating plasticity
KW  - Shakedown criterion
Y1  - 2005
ER  - 
TY  - CHAP
A1  - Kraft, Bodo
A1  - Retkowitz, Daniel
T1  - Graph Transformations for Dynamic Knowledge Processing
N2  - In: Proceedings of the 39th Annual Hawaii International Conference on System Sciences, 2006. HICSS '06 http://dx.doi.org/10.1109/HICSS.2006.200 The conceptual design phase at the beginning of the building construction process is not adequately supported by any CAD-tool. Conceptual design support needs regarding two aspects: first, the architect must be able to develop conceptual sketches that provide abstraction from constructive details. Second, conceptually relevant knowledge should be available to check these conceptual sketches. The paper deals with knowledge to formalize for conceptual design. To enable domain experts formalizing knowledge, a graph-based specification is presented that allows the development of a domain ontology and design rules specific for one class of buildings at runtime. The provided tool support illustrates the introduced concepts and demonstrates the consistency analysis between knowledge and conceptual design.
KW  - CAD
KW  - CAD
KW  - Bauingenieurwesen
KW  - CAD
KW  - civil engineering
Y1  - 2006
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  - Poghossian, Arshak
A1  - Schumacher, Kerstin
A1  - Kloock, Joachim P.
A1  - Rosenkranz, Christian
A1  - Schultze, Joachim W.
A1  - Müller-Veggian, Mattea
A1  - Schöning, Michael Josef
T1  - Functional testing and characterisation of ISFETs on wafer level by means of a micro-droplet cell
N2  - A wafer-level functionality testing and characterisation system for ISFETs (ionsensitive field-effect transistor) is realised by means of integration of a specifically designed capillary electrochemical micro-droplet cell into a commercial wafer prober-station. The developed system allows the identification and selection of “good” ISFETs at the earliest stage and to avoid expensive bonding, encapsulation and packaging processes for nonfunctioning ISFETs and thus, to decrease costs, which are wasted for bad dies. The developed system is also feasible for wafer-level characterisation of ISFETs in terms of sensitivity, hysteresis and response time. Additionally, the system might be also utilised for wafer-level testing of further electrochemical sensors.
KW  - Biosensor
KW  - Biosensorik
KW  - ISFET
KW  - Wafer
KW  - ISFET
KW  - wafer-level testing
KW  - capillary micro-droplet cell
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1259
ER  - 
TY  - CHAP
A1  - Wagner, Torsten
A1  - Schöning, Michael Josef
T1  - Preface of the Special Issue of I3S 2005 in Jülich (Germany)
N2  - International Symposium on Sensor Science, I3S 2005 <3; 2005; Juelich, Germany> In: Sensors 2006, 6, 260-261 ISSN 1424-8220
KW  - Biosensor
KW  - I3S 2005
KW  - International Symposium on Sensor Science
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1365
ER  - 
TY  - GEN
A1  - Staat, Manfred
T1  - Technische Mechanik. Vorlesungsmitschrift. Korrigierter Nachdr. der 3. Aufl.
N2  - Überarbeitete, korrigierte und ergänzte Version einer Vorlesungsmitschrift von Sebastian Krämer. 172 S. Inhaltsverzeichnis 0 Einführung in die Mechanik 1 Statik starrer Körper 2 Elastostatik (Festigkeitslehre) 3 Kinematik 4 Kinetik Literatur
KW  - Technische Mechanik
Y1  - 2006
ER  - 
TY  - GEN
A1  - Staat, Manfred
T1  - Engineering Mechanics. Lecture Notes. 2nd edition, translation of the 3rd corrected and extended German edition of "Technische Mechanik"
N2  - English translation of the corrected lectures notes of Sebastian Krämer. Contents 0 Introduction to Mechanics 1 Statics of Rigid Bodies 2 Elastostatics (Strength of Materials) 3 Kinematics 4 Kinetics Literature
KW  - Technische Mechanik
KW  - Mechanics
KW  - Statics
KW  - Elastostatics
KW  - Kinematics
KW  - Kinetics
Y1  - 2006
ER  - 
TY  - GEN
A1  - Staat, Manfred
A1  - Barry, Steve
T1  - Continuum Mechanics with an Introduction to the Finite Element Method / Steve Barry; Manfred Staat. With extensions by Manfred Staat.
N2  - Contents: 1 Introduction 2 One Dimensional Continuum Mechanics 3 Tensors 4 Three Dimensional Stress and Strain 5 Conservation Laws 6 Contiunuum Modelling 7 Plain Problems 8 Questions 9 Reference Information
KW  - Technische Mechanik
KW  - Finite-Elemente-Methode
Y1  - 2006
ER  - 
TY  - CHAP
A1  - Srivastava, Alok
A1  - Singh, Virendra
A1  - Dhand, Chetna
A1  - Kaur, Manindar
A1  - Singh, Tejvir
A1  - Witte, Katrin
A1  - Scherer, Ulrich W.
T1  - Study of swift heavy ion modified conduction polymer composites for application as gas sensor
N2  - A polyaniline-based conducting composite was prepared by oxidative polymerisation of aniline in a polyvinylchloride (PVC) matrix. The coherent free standing thin films of the composite were prepared by a solution casting method. The polyvinyl chloride-polyaniline composites exposed to 120 MeV ions of silicon with total ion fluence ranging from 1011 to 1013 ions/cm2, were observed to be more sensitive towards ammonia gas than the unirradiated composite. The response time of the irradiated composites was observed to be comparably shorter. We report for the first time the application of swift heavy ion modified insulating polymer conducting polymer (IPCP) composites for sensing of ammonia gas.
KW  - Biosensor
KW  - Conducing polymer
KW  - ammonia gas sensors
KW  - swift heavy ions
KW  - polymer composites
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1345
ER  - 
TY  - CHAP
A1  - Chaiyboun, Ali
A1  - Traute, Rüdiger
A1  - Kiesewetter, Olaf
A1  - Ahlers, Simon
A1  - Müller, Gerhard
A1  - Doll, Theodor
T1  - Modular analytical multicomponent analysis in gas sensor arrays
N2  - A multi-sensor system is a chemical sensor system which quantitatively and qualitatively records gases with a combination of cross-sensitive gas sensor arrays and pattern recognition software. This paper addresses the issue of data analysis for identification of gases in a gas sensor array. We introduce a software tool for gas sensor array configuration and simulation. It concerns thereby about a modular software package for the acquisition of data of different sensors. A signal evaluation algorithm referred to as matrix method was used specifically for the software tool. This matrix method computes the gas concentrations from the signals of a sensor array. The software tool was used for the simulation of an array of five sensors to determine gas concentration of CH4, NH3, H2, CO and C2H5OH. The results of the present simulated sensor array indicate that the software tool is capable of the following: (a) identify a gas independently of its concentration; (b) estimate the concentration of the gas, even if the system was not previously exposed to this concentration; (c) tell when a gas concentration exceeds a certain value. A gas sensor data base was build for the configuration of the software. With the data base one can create, generate and manage scenarios and source files for the simulation. With the gas sensor data base and the simulation software an on-line Web-based version was developed, with which the user can configure and simulate sensor arrays on-line.
KW  - Biosensor
KW  - Main sensitivity
KW  - cross sensitivity
KW  - matrix method
KW  - gas sensor array
KW  - modelling
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1358
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  - Koplin, Tobias J.
A1  - Siemons, Maike
A1  - Océn-Valéntin, César
A1  - Sanders, Daniel
A1  - Simon, Ulrich
T1  - Workflow for high throughput screening of gas sensing materials
N2  - The workflow of a high throughput screening setup for the rapid identification of new and improved sensor materials is presented. The polyol method was applied to prepare nanoparticular metal oxides as base materials, which were functionalised by surface doping. Using multi-electrode substrates and high throughput impedance spectroscopy (HT-IS) a wide range of materials could be screened in a short time. Applying HT-IS in search of new selective gas sensing materials a NO2-tolerant NO sensing material with reduced sensitivities towards other test gases was identified based on iridium doped zinc oxide. Analogous behaviour was observed for iridium doped indium oxide.
KW  - Biosensor
KW  - High throughput experimentation
KW  - gas sensor
KW  - metal oxide
KW  - doping
KW  - impedance spectroscopy
KW  - nitrogen oxides
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1407
ER  - 
TY  - CHAP
A1  - Näther, Niko
A1  - Juárez, Leon M.
A1  - Emmerich, Rüdiger
A1  - Berger, Jörg
A1  - Friedrich, Peter
A1  - Schöning, Michael Josef
T1  - Detection of hydrogen peroxide (H2O2) at exposed temperatures for industrial processes
N2  - An H2O2 sensor for the application in industrial sterilisation processes has been developed. Therefore, automated sterilisation equipment at laboratory scale has been constructed using parts from industrial sterilisation facilities. In addition, a software tool has been developed for the control of the sterilisation equipment at laboratory scale. First measurements with the developed sensor set-up as part of the sterilisation equipment have been performed and the sensor has been physically characterised by optical microscopy and SEM.
KW  - Biosensor
KW  - Gas sensor
KW  - hydrogen peroxide
KW  - sterilisation
KW  - catalytic decomposition
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1418
ER  - 
TY  - CHAP
A1  - Wagner, Thorsten
A1  - Kohl, Claus-Dieter
A1  - Fröba, Michael
A1  - Tiemann, Michael
T1  - Gas sensing properties of ordered mesoporous SnO2
N2  - We report on the synthesis and CO gas-sensing properties of mesoporous tin(IV) oxides (SnO2). For the synthesis cetyltrimethylammonium bromide (CTABr) was used as a structure-directing agent; the resulting SnO2 powders were applied as films to commercially available sensor substrates by drop coating. Nitrogen physisorption shows specific surface areas up to 160 m2·g-1 and mean pore diameters of about 4 nm, as verified by TEM. The film conductance was measured in dependence on the CO concentration in humid synthetic air at a constant temperature of 300 °C. The sensors show a high sensitivity at low CO concentrations and turn out to be largely insensitive towards changes in the relative humidity. We compare the materials with commercially available SnO2-based sensors.
KW  - Biosensor
KW  - Tin oxide
KW  - sensing properties
KW  - CO
KW  - humidity
Y1  - 2006
U6  - http://nbn-resolving.de/urn/resolver.pl?urn:nbn:de:hbz:a96-opus-1422
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  -