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    Issues in designing object management systems
    (1990) Clow, Geoff; Plödereder, Erhard
    This paper summarizes the discussions of the Object Management System (OMS) session at the Chinon Workshop. The session identified numerous capabilities which might be required in an OMS. The facilities which were agreed upon as essential to an OMS are presented in Section 1, OMS Core Facilities. A number of issues in the realization of these and other capabilities, influenced in part by specific application scenarios, are discussed in Section 2, OMS Requirements Issues. Promising applications requiring further investigation can be found in Section 3, Perceptions for the Future. Some global observations on the past and future conduct of the OMS field are summarized in Section 4, Concluding Observations.
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    Computer simulation of anchoring technique in reinforced concrete beams
    (1990) Cervenka, Vladimir; Pukl, Radomir; Eligehausen, Rolf
    The load transfer in reinforced concrete structures by means of anchoring elements is very common in modern concrete technology. Anchoring elements are often inserted in the bottom surface of a structure and the load is transfered by tensile action of the concrete. In case of shear failure, the anchores are located in the most exposed tensile zone of beams. The shear failure can be thus influenced by anchoring elements. This effect was analysed by means of the finite element program SBETA, which is based on the nonlinear-elastic constitutive model. The comparison with experiments for several loading configurations was made. In the second part a computer simulation of similar experiments was conducted.
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    Diagnosis and modelling of Alzheimer's disease through neural network analyses of PET studies
    (1990) Kippenhan, Jonathan Shane; Nagel, Joachim H.
    The back-propagation neural network algorithm was applied to the analysis of regional patterns in cerebral function, as demonstrated in positron emission tomography (PET). A trained network was able to successfully distinguish PET scans of normal subjects from PET scans of Alzheimer's Disease patients. It is concluded that the combination of PET and neural networks is a useful diagnostic tool for Alzheimer's Disease. A new paradigm for back-propagation learning is discussed which emphasizes its similarity to template matching. It is demonstrated that, under certain circumstances, the back-propagation network can be used as an estimation tool, as well as a classification tool, i.e., a trained neural network can indicate the criteria by which its classifications are performed.
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    Simulation mit Supercomputern : ein neues Werkzeug der Physik
    (1990) Ruder, Hanns; Ertl, Thomas; Geyer, Florian; Herold, Heinz; Kraus, Ute; Nollert, Hans-Peter; Rebetzky, Andreas; Schweizer, Wolfgang; Zahn, Corvin
    Unser Wissen über die Struktur des Kosmos und die darin enthaltenen Objekte stammt aus der sorgfältigen Analyse der auf der Erde einfallenden elektromagnetischen Strahlung,verbunden mit einer theoretischen Modellierung im Rahmen der von uns erforschten Naturgesetze. Die sprunghafte Zunahme unserer Kenntnisse in den letzten zwei Jahrzehnten verdanken wir vor allem den vielen Forschungssatelliten, die die Beobachtung kosmischer Objekte ohne die störenden Einflüsse unserer Atmosphäre erlauben. Speziell im weichen Röntgenbereich ist dadurch eine Beobachtung überhaupt erst möglich , und es ist gerade dieser Spektralbereich, der uns wesentlich neue Erkenntnisse über hochinteressante Objekte geliefert hat, da intensive Röntgenstrahlung nur unter sehr extremen physikalischen Bedingungen entsteht. Die in diesen Röntgenemissionsgebieten vorherrschenden Temperaturen, Magnet- und Gravitationsfelder sind so extrem, daß sie in irdischen Labors nicht realisiert werden können. Folglich bleibt nur die Möglichkeit, die Eigenschaften der Materie und die unter diesen Bedingungen ablaufenden physikalischen Prozesse theoretisch zu berechnen, um so - im Vergleich mit den Beobachtungen - zu zuverlässigen Aussagen über die Struktur dieser kosmischen Objekte zu gelangen.
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    Post-processing tools for nonlinear fe analysis of concrete structures
    (1990) Cervenka, Vladimir; Pukl, Radomir; Eligehausen, Rolf
    Finite clement analysis of the cracking process in concrete structures brings new requirements for the post-processing environment. Crack direction and location are important for identification of the failure mode. The problem have been solved in the finite element program SBETA which was developed by the authors for simulation of the failure processes in reinforced concrete structures. The post-processing system creates the graphical images of crack patterns. Graphical sequences for simulation can be generated.
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    Verantwortung in Wissenschaft und Technik : Fragen und Probleme
    (1990) Hubig, Christoph
    Das neue Problemfeld einer Ethik der Wissenschaft und Technik erstreckt sich von ihren handlungstheoretischen Grundlagen über die Erschließung der neuen Dimensionen der Folgen (Risiken und Gratifikationen) bis hin zu den Instanzen (Wirtschaft, Politik) als Organisationen und Institutionen, die in die neue komplexe Verantwortungsproblematik involviert sind, jenseits der alten Wertfreiheitsdiskussion und der alten Forderung nach der Verantwortung des Wissenschaftlers und Technikers als Individuum.
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    Proton relaxation in the superconducting organic solid (BEDT-TTF)2Cu(NCS)2: evidence for relaxation by localized paramagnetic centers
    (1990) Klutz, Thomas; Haeberlen, Ulrich; Schweitzer, Dieter
    The nonexponential character of the build-up of the nuclear magnetization usually increases on lowering the temperature. Superconducting fluctuations have been offered in a speculative way as an explanation for the nonexponential spin relaxation. We have observed the same relaxation behaviour in our investigation of the proton spin relaxation in (BEDT-TTF)2Cu(NCS)2 which is an organic conductor at room temperature and becomes a superconductor at Tc=10.4 K at ambient pressure. As we noticed during preliminary measurements that the degree of deviation from exponential relaxation depends on the sample under study we decided to do experiments under controlled conditions of sample preparation.
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    A synthesis approach to reduce scan design overhead
    (1990) Eschermann, Bernhard; Wunderlich, Hans-Joachim
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    The effectiveness of different test sets for PLAs
    (1990) Maxwell, Peter C.; Wunderlich, Hans-Joachim
    It has been theoretically demonstrated that the single stuck-at fault model for a PLA does not cover as many faults as the single crosspoint model. What has not been demonstrated is the real relative effectiveness of test sets generated using these models. This paper presents the results of a study involving presenting a number of test sets to fabricated PLAs to determine their effectiveness. The test sets included weighted random patterns, of particular interest owing to PLAs being random resistant. Details are given of a method to generate weights, taking into account a PLA's structure.
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    Tools and devices supporting the pseudo-exhaustive test
    (1990) Hellebrand, Sybille; Wunderlich, Hans-Joachim
    In the paper logical cells and algorithms are presented supporting the design of pseudo-exhaustively testable circuits. The approach is based on real hardware segmentation, instead of path-sensitizing. The developed cells segment the entire circuits into exhaustively testable parts, and the presented algorithms place these cells, under the objective to minimize the hardware overhead. The approach is completely compatible with the usual LSSD-rules. The analysis of the well-known benchmark circuits shows only little additional hardware costs.