TY - JOUR A1 - Streun, M. A1 - Brandenburg, G. A1 - Larue, H. A1 - Zimmermann, E. A1 - Ziemons, Karl A1 - Halling, H. T1 - Pulse recording by free-running sampling JF - 2000 IEEE Nuclear Science Symposium Conference Record, Vol. 2 N2 - Pulses from a position-sensitive photomultiplier (PS-PMT) are recorded by free running ADCs at a sampling rate of 40 MHz. A four-channel acquisition-board has been developed which is equipped with four 12 bit-ADCs connected to one FPGA (field programmable gate array). The FPGA manages data acquisition and the transfer to the host computer. It can also work as a digital trigger, so a separate hardware-trigger can be omitted. The method of free running sampling provides a maximum of information, besides the pulse charge and amplitude also pulse shape and starting time are contained in the sampled data. These informations are crucial for many tasks such as distinguishing between different scintillator materials, determination of radiation type, pile-up recovery, coincidence detection or time-of-flight applications. The absence of an analog integrator allows coping with very high count rates. Since this method is going to be employed in positron emission tomography (PET), the position of an event is another important information. The simultaneous readout of four channels allows localization by means of center-of-gravity weighting. First results from a test setup with LSO-scintillators coupled to the PS-PMT are presented Y1 - 2000 SN - 1082-3654 SP - 9/179 EP - 9/181 ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Traglastanalyse - ein strukturmechanisches Verfahren zur Beurteilung von gerissenen Bauteilen und Verbindungen JF - Festigkeits- und Bruchverhalten von Fügeverbindungen : 32. Tagung des DVM-Arbeitskreises Bruchvorgänge ; 22. und 23. Februar 2000 in Berlin / Richard, H. A. [Hrsg] Y1 - 2000 N1 - DVM-Bericht 232 SP - 183 EP - 192 PB - Deutscher Verband für Materialforschung und -prüfung CY - Berlin ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Reliability Analysis of Elasto-Plastic Structures under Variable Loads JF - Inelastic analysis of structures under variable loads : theory and engineering applications / Maier, G.; Weichert, D. [ed] Y1 - 2000 SN - 0-7923-6645-X SP - 269 EP - 288 PB - Kluwer Academic Publ. CY - Dordrecht ER - TY - JOUR A1 - Staat, Manfred A1 - Heitzer, M. T1 - Direct FEM approach to design-by-analysis of pressurized components JF - Achema 2000 : Sonderausgabe / Linde. [Hrsg.: Linde AG. Red.: Volker R. Leski] Y1 - 2000 SP - 79 EP - 81 PB - Linde AG CY - Wiesbaden 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 KW - FEM KW - Einspielanalyse KW - shakedown KW - limit load KW - reliability analysis KW - FEM KW - direct method 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 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 - Siedenbiedel, Georg T1 - Der Auslandsabsatz als Gegenstand strategischer Entscheidungen JF - Marketing-Management für Ingenieure und Informatiker /Pepels. Werner (Hrsg.) Y1 - 2000 SP - 207 EP - 234 PB - Fortis [u.a.] CY - Köln [u.a.] ER - TY - JOUR A1 - Selmer, Thorsten A1 - Kahnt, Jörg A1 - Goubeaud, Marcel A1 - Shima, Seigo T1 - The biosynthesis of methylated amino acids in the active site region of methyl-coenzyme M reductase / Selmer, Thorsten ; Kahnt, Jörg ; Goubeaud, Marcel ; Shima, Seigo ; Grabarse, Wolfgang ; Ermler, Ulrich ; Thauer, Rudolf K. JF - Journal of Biological Chemistry. 275 (2000), H. 6 Y1 - 2000 SN - 1083-351X SP - 3775 EP - 3760 ER - TY - JOUR A1 - Selmer, Thorsten A1 - Brüser, Thomas A1 - Dahl, Christiane T1 - ADP Sulfurylase" from Thiobacillus denitrificans Is an Adenylylsulfate:Phosphate Adenylyltransferase and Belongs to a New Family of Nucleotidyltransferases / Brüser, Thomas ; Selmer, Thorsten ; Dahl, Christiane JF - Journal of Biological Chemistry. 275 (2000), H. 3 Y1 - 2000 SN - 1083-351X SP - 1691 EP - 1690 ER - TY - JOUR A1 - Schütz, S. A1 - Schöning, Michael Josef A1 - Schroth, P. A1 - Weißbecker, B. A1 - Kordos, P. A1 - Lüth, H. A1 - Hummel, Hans E. T1 - An insectbased BioFET as a bioelectronic nose JF - Sensors and Actuators B. 65 (2000), H. 1-3 Y1 - 2000 SN - 0925-4005 SP - 291 EP - 295 ER -