TY  - JOUR
A1  - Heuermann, Holger
A1  - Schiek, Burkhard
T1  - The In-Fixture Calibration Procedure Line-Network-Network-LNN
JF  - Conference proceedings : monday 6th to thursday 9th september 1993, Palacio de Congresos, Madrid, Spain ; [the international conference and exhibition designed for the Microwave Community]
Y1  - 1992
SN  - 0-946821-23-2
N1  - European Microwave Conference <23, 1993, Madrid>
SP  - 500
EP  - 505
PB  - Reed Exhibition Companies
CY  - Tunbridge Wells
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Schiek, Burkhard
T1  - Scattering Parameter Measurements of Microstrip Devices using the Double-LNN Calibration Technique
JF  - Conference proceedings : [Palais des Festivals et des Congrès Cannes, France, 5 - 8 September 1994]
Y1  - 1994
SN  - 0-9518032-5-5
N1  - European Microwave Conference <24, 1994, Cannes>
PB  - Nexus Business Communications
CY  - Swanley
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Schiek, Burkhard
T1  - The double-LNN Calibration technique for scattering parameter measurements of microstrip devices
JF  - Conference proceedings
Y1  - 1995
N1  - European Microwave Conference <25, 1995, Bologna>
SP  - 343
EP  - 347
PB  - NEXUS House
CY  - Kent
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
T1  - LZY: A Self-Calibration Approach in Competition to the LRM Method for On-Wafer Measurements
Y1  - 1995
N1  - 45th ARFTG Conference digest, Spring 1995 : [conference topic: Testing and design of RFIC'S], May 19, 1995, Orange County Convention Center, Orlando, Florida / Automatic RF Techniques Group. Publications chairman: Ed Godshalk;  ARFTG Conference digest ; 4
SP  - 129
EP  - 136
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
T1  - Sure Methods of On-Wafer Scattering Parameter Measurements with Self-Calibration Procedures
Y1  - 1996
N1  - 46th ARFTG conference digest : November 30 - December 1. 1995, Safari Resort, Scottsdale, Arizona / Automatic RF Techniques Group. [Publ. chairman: Ed. Godshalk]
SP  - 136
EP  - 145
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
T1  - Microwave On-Wafer Measurements with Activ Needle Probe Tips
Y1  - 1997
N1  - 47th ARFTG Conference digest : June 20 - 21, 1996, Moscone Convention Center, San Francisco, California / Automatic RF Techniques Group. [Publication chair: Ed Godshalk
SP  - 208
EP  - 214
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Schiek, Burkhard
T1  - Results of Network Analyzer Measurements with Leakage Errors Corrected with the TMS-15-Term Procedure
Y1  - 1994
N1  - 1994 IEEE MTT-S International Microwave Symposium digest : May 23 - 27, 1994, San Diego Convention Center, San Diego, California / H. J. Kuno, ed.
SP  - 1361
EP  - 1364
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Baumann, F.-M.
A1  - Fauth, G.
A1  - Albert, M.
T1  - Results of Network Analyzer Measurements with Leakage Errors Corrected with the TMS-15-Term Procedure
JF  - On-Line Moisture Analysis of Raw Coal
Y1  - 1994
N1  - 1993 International Symposium on On-Line Analysis of Coal : Vienna ; [proceedings].
SP  - 1361
EP  - 1364
ER  - 
TY  - JOUR
A1  - Fabo, Sabine
ED  - Könches, Barbara
T1  - Welcome to the training: Actionist Respoke interaktiv by Michael Jonoschek und Rüdiger Schlömer
JF  - Bilder-Codes : Internationaler Medienkunstpreis 2002
Y1  - 2002
SN  - 3-928201-28-X
SP  - 41
EP  - 48
PB  - ZKM
CY  - Karlsruhe
ER  - 
TY  - JOUR
A1  - Wrede, Oliver
T1  - Mnemotechnik in graphischen Benutzeroberflächen
JF  - Form <Basel> / Form-Diskurs : Zeitschrift für Design und Theorie. 1 (1996), H. 2
Y1  - 1996
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Schiek, Burkhard
T1  - LNN (Line-Network-Network): Verfahren zur Kalibrierung von Netzwerkanalysatoren
JF  - Kleinheubacher Berichte : Vorträge und Berichte der gemeinsamen Tagung des U.R.S.I.-Landesausschusses in der Bundesrepublik Deutschland / Hrsg.: Deutsche Telekom AG. 36. 1992 (1992)
Y1  - 1992
SP  - 327
EP  - 335
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Schiek, Burkhard
T1  - LNN( Line-Network-Network): The In-Fixture Calibration Procedure
Y1  - 1993
N1  - XXIVth General Assembly of the International URSI, Kyoto
SP  - 149
EP  - 149
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Schiek, Burkhard
T1  - A Fast and Robust Procedure for the Determination of the Scattering Parameters for Network Analyzer Calibration
Y1  - 1992
N1  - Precision electromagnetic measurements : conference Paris, 9-12 June 1992 = Conférence sur les Mesures Electromagnétiques de Précision.
SP  - 373
EP  - 374
CY  - Paris
ER  - 
TY  - JOUR
A1  - Hagemann, Hans-Jürgen
A1  - Backhaus, U.
A1  - Goessner, S.
T1  - Collaborative eLearning Concepts for University Level Online Laboratory Courses in Engineering. U. Backhaus, S. Goessner, H. J. Hagemann
JF  - Proceedings Online Educa Berlin: 8th International Conference on Technology Supported Learning & Training. 2002
Y1  - 2002
N1  - Online Educa <2002, Berlin>
SP  - 62
EP  - 66
ER  - 
TY  - JOUR
A1  - Krause, Gregor
A1  - Fruth, Bernhard
T1  - Dielectric Properties of Polyolefins Stressed by High Electrical Fields. Fruth, B. ; Krause, G.
Y1  - 1987
N1  - Fifth International Symposium on High Voltage Engineering : Proceedings; Braunschweig, Stadthalle, August, 24-28, 1987 / International Symposium on High Voltage Engineering <5, 1987, Braunschweig>
ER  - 
TY  - JOUR
A1  - Krause, Gregor
A1  - Göttlich, S.
A1  - Möller, K.
A1  - Meurer, D.
T1  - Space Charge Phenomena in Partially Crystalline Polymers: On-Line Measurement of Charge Carrier Motion under High AC-Field Strength / G. Krause, S. Göttlich, K. Möller, D. Meurer
JF  - Proceedings of the 3rd International Conference on Conduction and Breakdown in Solid Dielectrics : Trondheim, Norway ... 1989
Y1  - 1989
N1  - International Conference on Conduction and Breakdown in Solid Dielectrics <3, 1989, Trondheim>
PB  - IEEE
CY  - Piscataway, N.J.
ER  - 
TY  - JOUR
A1  - Krause, Gregor
A1  - Neubert, R.
A1  - Pietsch, R.
T1  - Investigations of Electrical Aging in Polymers under High AC-Field Strength
JF  - 1990 annual report : October 28 - October 31, 1990 / sponsored by the IEEE Dielectrics and Electrical Insulation Society
Y1  - 1990
N1  - Conference on Electrical Insulation and Dielectric Phenomena ; (59, 1990, Pocono Manor, Pa.)
PB  - IEEE Service Center
CY  - Piscataway, N.J
ER  - 
TY  - JOUR
A1  - Krause, Gregor
T1  - High Field Phenomena of Polymeric Insulation Investigated at PE Needle-Plane Specimen
JF  - Seventh International Symposium on High Voltage Engineering : Dresden, August 26 - 30, 1991 / Technische Universität Dresden
Y1  - 1991
N1  - International Symposium on High Voltage Engineering ; (7, 1991, Dresden); International Symposium on High Voltage Engineering (ISH) ; (7 : ; 1991.08.26-30 : ; Dresden)
PB  - TU Dresden
CY  - Dresden
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Kurzawa, R.
A1  - Schmitt, W.
A1  - Güntherodt, G.
T1  - Spin-resolved photoemission study of in situ grown epitaxial Fe layers on W(110). Kurzawa, R.; Kämper, K.-P.; Schmitt, W.; Güntherodt, G.
JF  - Solid State Communications. 60 (1986), H. 10
Y1  - 1986
SN  - 0038-1098
SP  - 777
EP  - 780
ER  - 
TY  - JOUR
A1  - Siepmann, Thomas
A1  - Rupietta, D.
T1  - Closer to the customer with computerized  product support
JF  - Technische Mitteilungen Krupp (1993)
Y1  - 1993
CY  - Essen
ER  - 
TY  - JOUR
A1  - Siepmann, Thomas
A1  - Schuh, G.
A1  - Levering, V.
T1  - PROPLAN / Schuh, G.; Siepmann, Th.; Levering, V.
JF  - Handbook on architectures of information systems : with 24 tables / Peter Bernus ... (ed.)
Y1  - 1998
SN  - 3-540-64453-9
N1  - International handbooks on information systems ; 1
PB  - Springer
CY  - Berlin [u.a.]
ER  - 
TY  - JOUR
A1  - Siepmann, Thomas
T1  - Exploitation Plan of the TELEflow Project
Y1  - 1999
N1  - 4th Framework Programme Report
CY  - Brussels
ER  - 
TY  - JOUR
A1  - Fabo, Sabine
T1  - Arts and media : towards an universal understanding
JF  - Leonardo
Y1  - 1993
SN  - 0024-094X
VL  - 26(1993)
IS  - 4
SP  - 316
EP  - 319
ER  - 
TY  - JOUR
A1  - Hagemann, Hans-Jürgen
A1  - Bachmann, P.K.
A1  - Lade, H.
A1  - Leers, D.
T1  - CVD Diamond Growth: Gas Compositions and Film Properties / P.K. Bachmann, H.J. Hagemann, H. Lade, D. Leers, D.U. Wiechert and H. Wilson
JF  - Advanced materials '94 : proceedings of the NIRIM International Symposium on Advanced Materials '94, Tsukuba, Japan, March 13 - 17, 1994 / National Institute for Research in Inorganic Materials. Ed. by M. Kamo ...
Y1  - 1994
N1  - NIRIM International Symposium on Advanced Materials ; 1994 (Tsukuba) : 1994.03.13-17
SP  - 115
EP  - 120
PB  - International Communications Specialists
CY  - Tokyo
ER  - 
TY  - JOUR
A1  - Hagemann, Hans-Jürgen
A1  - Bachmann, P.K.
A1  - Lade, H.
A1  - Leers, D.
T1  - Diamond chemical vapor deposition: gas compositions and film properties / Bachmann, P.K.; Hagemann, H.-J.; Lade, H; Leers, D.; Picht, F.; Wiechert, D.U.; Wilson, H.
JF  - Diamond, SiC and nitride wide bandgap semiconductors : symposium held April 4 - 8, 1994, San Francisco, California, U.S.A. / ed.: Calvin H. Carter, Jr. ...
Y1  - 1994
SN  - 1-55899-239-1
N1  - Materials Research Society symposium proceedings ; 339
SP  - 267
EP  - 277
CY  - Pittsburgh, Penn.
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Berg, U.
A1  - Begemann, M.
A1  - Hagemann, B. (u.a.)
T1  - Series production and testing of a micro motor. Serienfertigung und Prüfung eines Mikromotors
JF  - Actuator 98 : 6th International Conference on New Actuators ; 17 - 19 June, 1998, Bremen, Germany ; conference proceedings / ed.: Hubert Borgmann ...
Y1  - 1998
SN  - 3-933339-00-6
N1  - Konferenz-Einzelbericht: ACTUATOR, Internat. Conf. on New Actuators
SP  - 552
EP  - 555
PB  - Messe Bremen
CY  - Bremen
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Döpper, J.
A1  - Clemens, M.
A1  - Ehrfeld, W.
T1  - Micro gear pumps for dosing of viscous fluids. / Döpper, J. (u.a.)
JF  - Journal of Micromechanics and Microengineering. 7 (1997), H. 3
Y1  - 1997
SN  - 0960-1317
SP  - 230
EP  - 232
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Lehr, H.
A1  - Abel, S.
A1  - Döpper, J.
T1  - Microactuators as driving units for microrobotic systems. Herstellung von Mikroaktoren mit dem LIGA-Verfahren für Mikroroboter  / Lehr, H.; Abel, S.; Döpper, J.; Ehrfeld, W.; Hagemann, B.; Kämper, K.-P.; Michel, F.; Schulu, c.; Thürigen, C.
JF  - Proceedings of the SPIE - The International Society for Optical Engineering
Y1  - 1996
SN  - 0277-786X
N1  - Konferenz-Einzelbericht.
SP  - 202
EP  - 210
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
T1  - Development of low-cost injection moulded micropumps. Entwicklung von kostengünstigen, mittels Spritzguß hergestellten Mikropumpen / Döpper, J. (u.a.)
JF  - Actuator 96 : Conference Proceedings ; 5th International Conference on New Actuators ; 26- 28 June, Bremen, Germany / Ed.: Hubert Borgmann. Publ. by: AXON Technology Consult GmbH
Y1  - 1996
N1  - Konferenz-Einzelbericht: ACTUATOR, Internat. Conf. on New Actuators, 5
SP  - 37
EP  - 40
CY  - Bremen
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Sadeghfam, Arash
T1  - Novel balanced inductor for compact differential systems / Sadeghfam, Arash; Heuermann, Holger
JF  - Conference proceedings : Tuesday 12th, Wednesday 13th and Thursday 14th October, [RAI International Exhibition and Congress Centre, Amsterdam ; part of European Microwave Week 2004] / EuMA, European Microwave Association
Y1  - 2004
SN  - 1-580-53992-0
N1  - European Microwave Conference ; (34, 2004, Amsterdam) ; European Microwave Week ; (7, 2004, Amsterdam)
SP  - 709
EP  - 712
PB  - Horizon House Publ.
CY  - London
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Erkens, Holger
T1  - Blocking structures for mixed-mode systems. / Erkens, Holger ; Heuermann, Holger
JF  - Conference proceedings : Tuesday 12th, Wednesday 13th and Thursday 14th October, [RAI International Exhibition and Congress Centre, Amsterdam ; part of European Microwave Week 2004] / EuMA, European Microwave Association. Vol. 1
Y1  - 2004
SN  - 1-580-53992-0
N1  - European Microwave Conference ; (34, 2004, Amsterdam) ; European Microwave Week ; (7, 2004, Amsterdam)
SP  - 297
EP  - 300
PB  - Horizon House Publ.
CY  - London
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
A1  - Rumiantsev, A.
A1  - Schott, S.
T1  - Advanced on-wafer multiport calibration methods for mono- and mixed-mode device characterization
JF  - On wafer characterization : 63rd ARFTG conference digest, spring 2004, 11 June 2004, Fort Worth, TX / Automatic RF Techniques Group. [Conference chair: John Cable. Publication chair: J. G. Burns]
Y1  - 2004
SN  - 0-7803-8371-0
N1  - Microwave Theory and Techniques Society. ; Automatic RF Techniques Group ; ARFTG conference ; (63 : ; 2004.06.11 : ; Fort Worth, Tex.)
SP  - 91
EP  - 96
PB  - IEEE Operations Center
CY  - Piscataway, NJ
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
T1  - GSOLT: the calibration procedure for all multi-port vector network analyzers
JF  - IEEE MTT-S International Microwave Symposium digest : Philadelphia, Pennsylvania, 8 - 13 June 2003 ; [including: 2003 International Microwave Symposium digest, vol. 1-3, RF Integrated Circuit Symposium digest, Automatic RF Techniques Group Symposium digest . Vol. 3
Y1  - 2003
SN  - 0-780-37696-X
N1  - Nebent.: 2003 IEEE MTT-S International Microwave Symposium
SP  - 1815
EP  - 1818
PB  - IEEE
CY  - Piscataway, NJ
ER  - 
TY  - JOUR
A1  - Samm, Doris
A1  - Faissner, H.
A1  - Frenzel, E.
A1  - Heinrigs, W.
T1  - Limit on axion decay into an electron pair / H. Faissner, E. Frenzel, W. Heinrigs, A. Preussger, D. Samm und U. Samm
JF  - Physics Letters B. Vol. 96 (1980), H. Issues 1-2
Y1  - 1980
SP  - 201
EP  - 205
ER  - 
TY  - JOUR
A1  - Samm, Doris
A1  - Faissner, H.
A1  - Frenzel, E.
A1  - Heinrigs, W.
T1  - Observation of the two-photon decay of a light penetrating particle / H. Faissner, E. Frenzel, W. Heinrigs, A. Preussger, D. Samm und U. Samm
JF  - Physics Letters B. Vol. 103 (1980), H. Issues 3
Y1  - 1980
SP  - 234
EP  - 240
ER  - 
TY  - JOUR
A1  - Samm, Doris
A1  - Faissner, H.
A1  - Heinrigs, W.
A1  - Preussger, A.
T1  - Search for the two-photon decay of a light penetrating particle from a 590 MeV proton beam dump / Faissner, H.; Heinrigs, W.; Preussger, A.; Reitz, J.; Samm, D. [u.a.]
JF  - Zeitschrift für Physik, C Particles and Fields. 44 (1989), H. 4
Y1  - 1989
SP  - 557
EP  - 566
ER  - 
TY  - JOUR
A1  - Kämper, Klaus-Peter
A1  - Picard, Antoni
A1  - Brill, Manfred
A1  - Cassel, Detlef (u.a.)
T1  - The Virtual Cleanroom – a new tool in teaching MST process technologies
JF  - mst news International newsletter on micro - nano Integration (2003)
Y1  - 2003
SN  - 0948-3128
SP  - 35
EP  - 36
ER  - 
TY  - JOUR
A1  - Samm, Doris
A1  - Bosetti, P.-C.
T1  - Testmessungen an einem grossflaechigen (Durchmesser 35 cm) Photomultiplier Test measurements of a large-area (diameter 35 cm) photomultiplier / Bosetti, P.-C.; ... Samm, D. [u.a.]
JF  - Verhandlungen der Deutschen Physikalischen Gesellschaft. 25 (1990), H. 1
Y1  - 1990
N1  - Fruehjahrstagung des Fachausschusses Teilchenphysik der Deutschen Physikalischen Gesellschaft e.V. (DPG), Hamburg (Germany), 21-24 Mar 1990
SP  - 33
EP  - 33
ER  - 
TY  - JOUR
A1  - Samm, Doris
A1  - Bosetti, P.-C.
T1  - DUMAND und die Suche nach extraterrestrischen Neutrinos / DUMAND and the search for extraterrestrial neutrinos / Bosetti, P.-C.; ... Samm, D. [u.a.]
JF  - Verhandlungen der Deutschen Physikalischen Gesellschaft. 25 (1990), H. 1
Y1  - 1990
N1  - Fruehjahrstagung des Fachausschusses Teilchenphysik der Deutschen Physikalischen Gesellschaft e.V. (DPG), Hamburg (Germany), 21-24 Mar 1990
SP  - 88
EP  - 88
ER  - 
TY  - JOUR
A1  - Samm, Doris
A1  - Faissner, H.
A1  - Göttlicher, P.
A1  - Matela, H.
T1  - Search for scalar and pseudoscalar bosons emitted in nuclear decays via their interactions / Faissner, H.; Goettlicher, P. ; Matela, H. ; Samm, D.
JF  - Zeitschrift für Physik A Hadrons and Nuclei. 341 (1992), H. 3
Y1  - 1992
SP  - 359
EP  - 364
ER  - 
TY  - JOUR
A1  - Samm, Doris
A1  - Faissner, H.
A1  - Moers, T.
A1  - Priem, R.
T1  - Modular wall-less drift chamber for muon detection at the LHC / H. Faissner, Th. Moers, R. Priem, ... , D. Samm [u.a.]
JF  - Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment. 330 (1993), H. 1-2
Y1  - 1993
SP  - 76
EP  - 82
ER  - 
TY  - JOUR
A1  - Samm, Doris
T1  - DUMAND and the search for high energy neutrino point sources / Samm, Doris [u.a.]
JF  - Trends in astroparticle physics / ed. by Peter Christian Bosetti
Y1  - 1994
SN  - 3-8154-3017-8
N1  - (Teubner-Texte zur Physik; Bd. 28); International Conference on Trends in Astroparticle-Physics ; (2 : ;
SP  - 9
EP  - 20
PB  - Teubner
CY  - Stuttgart
ER  - 
TY  - JOUR
A1  - Heuermann, Holger
T1  - A Synthesis Technique for Mono- and Mixed-Mode Symmetrical Filter
JF  - Conference proceedings : Tuesday 12th, Wednesday 13th and Thursday 14th October, [RAI International Exhibition and Congress Centre, Amsterdam ; part of European Microwave Week 2004] / EuMA, European Microwave Association . Vol. 1
Y1  - 2004
SN  - 1-580-53992-0
N1  - European Microwave Conference ; (34, 2004, Amsterdam) ; European Microwave Week ; (7, 2004, Amsterdam)
SP  - 309
EP  - 312
PB  - Horizon House Publ
CY  - London
ER  - 
TY  - JOUR
A1  - Fredebeul-Krein, Markus
T1  - The case for a more binding WTO agreement on regulatory principles in telecommunication markets
JF  - Telecommunications policy. vol. 23 (1999), H. afl. 9
Y1  - 1999
SN  - 0308-5961
SP  - 625
EP  - 644
ER  - 
TY  - JOUR
A1  - Fredebeul-Krein, Markus
T1  - Telecommunications and WTO discipline : an assessment of the WTO agreement on telecommunication services
JF  - Telecommunications policy. 21 (1997), H. 6
Y1  - 1997
SN  - 0308-5961
SP  - 477
EP  - 491
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  - 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  - 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  - Gebhardt, Andreas
T1  - Generative Manufacturing of Ceramic Parts "Vision Rapid Prototyping"
N2  - Table of Contents Introduction 1. Generative Manufacturing Processes 2. Classification of Generative Manufacturing Processes 3. Application of Generative Processes on the Fabrication of Ceramic Parts 3.1 Extrusion 3.2 3D-Printing 3.3 Sintering – Laser Sintering 3.4 Layer-Laminate Processes 3.5 Stereolithography (sometimes written: Stereo Lithography) 4. Layer Milling 5. Conclusion - Vision
KW  - Rapid prototyping
KW  - Rapid Technologie
KW  - Rapid Prototyping
Y1  - 2006
ER  -