Universität Stuttgart
Permanent URI for this communityhttps://elib.uni-stuttgart.de/handle/11682/1
Browse
Search Results
Item Open Access Languages, methods, and tools for software specification(1989) Ludewig, JochenSpecification systems consist of methods, languages, and tools; the languages may be more or less formal. In this paper, the general ideas of semi-formal specification systems are presented, and some examples are shown.Item Open Access Extending the relational algebra to capture complex objects(1989) Mitschang, BernhardAn important direction in database research for non-standard applications (e.g. engineering or design applications) deals with adequate support for complex objects. Without doubt, the provision of network structures and shared subobjects as well as support for dynamic object definition and appropriate manipulation facilities is urgently needed for natural and accurate modeling as well as for efficient processing of the applications' objects. These concepts are the major concern of the molecule-atom data model (MAD model) and its molecule algebra which is introduced in this paper. They make the model stand out compared to the relational model and even to models limited to hierarchical and statically defined complex objects. By means of the molecule algebra a precise and complete specification of one conceivable kind of complex object processing and its inherent semantics is provided. Furthermore, this algebra is used as a sound basis to express the semantics of the high level query language MOL (molecule query language) that is able to deal with complex objects in a descriptive manner.Item Open Access The synthesis of self-test control logic(1989) Haberl, Oliver F.; Wunderlich, Hans-JoachimIn recent years, many built-in self-test techniques have been proposed based on feedback shift-registers for pattern generation and signature analysis. But in general, these test-registers cannot test several modules of the chip concurrently, and they have to be controlled by external automatic test equipment. The authors propose a method to integrate additional test-control logic into the chip. On the basis of a register-transfer description of the circuit, the test control is derived, and a corresponding finite automation is synthesized. A hardware implementation is proposed, resulting in circuits where the entire self-test only consists in activating the test mode and clocking and evaluating the overall signature.Item Open Access Self-consistent modelling of pulsar magnetospheres(1989) Herold, Heinz; Ertl, Thomas; Finkbeiner, Bernd; Ruder, HannsThe magnetosphere of a rapidly rotating, strongly magnetized neutron star with aligned magnetic and rotational axes (parallel rotator) is modelled numerically. Including the radiation of the particles accelerated to relativistic energies as an efficient damping mechanism, we obtain a quasi-stationary selfconsistent solution to this classical problem. The numerical simulation, which was started from the well-known vacuum solution, yields a global magnetospheric structure that can be characterized by two regions of oppositely charged particles, which eventually produce a relativistic pulsar wind, separated by a vacuum gap of considerable extent.Item Open Access Optical methods of measuring rough surfaces(1989) Leonhardt, Klaus; Rippert, Karl-Heinz; Tiziani, Hans J.The statistical parameters of surfaces to be measured for industrial applications vary over several orders of magnitude. Surfaces with large slopes or edges are particularly difficult to be recorded. Some measuring methods developed in our laboratory are compared and the range of applications are discussed. For polished and fine ground glass and metal surfaces a heterodyne profilometer with a vertical resolution of 0.5 nm, lateral resolution of 0.6 μm, and large scanning length is discussed. The interferometer can be changed from single- to double-pass operation by rotation of a quarter-wave-plate. For rougher surfaces a profilometer of the photometric-balance type with resolution Rq < 4 nm and dynamic range of 20 μm and an interference microscope with automated fringe evaluation is described. An integral white light roughness sensor covers the roughness range 0.04μm to 10μm and measures independently mean roughness and autocorrelation width.Item Open Access scheinen + Infinitiv : eine oberflächengrammatische Analyse(1989) Pafel, JürgenDas Verb "scheinen" kennt drei verschiedene grammatische Verwendungen: mit finitem Nebensatz, mit zu-Infinitiv und mit Prädikativ. Wie in diesem, so haben auch in vielen anderen Fällen die Sätze trotz ihres Konstruktionsunterschieds genau dieselben Wahrheitsbedingungen. Der Grund dafür scheint der Umstand zu sein, daß das Verb in allen drei Verwendungen dasselbe bedeutet: einen bestimmten Typ von propositionaler Einstellung. Unsere Untersuchung führt zu folgender (vorläufigen) Sicht des Verhältnisses der drei Typen von scheinen-Konstruktionen: die syntaktischen Unterschiede, die sich an der Oberfläche zeigen, lassen sich auf keiner "tieferen" syntaktischen Analyseebene zum Verwinden bringen, sondern sind, was die Infinitiv- und die Prädikativ-Verwendung einerseits und die Nebensatzverwendung andererseits angeht, Ausdruck struktureller Unterschiede sowohl syntaktischer wie semantischer Natur.Item Open Access Simultaneous degradation of chloro- and methylaromatics via ortho pathway by genetically engineered bacteria and natural soil isolates(1989) Engesser, Karl-Heinrich; Pieper, Dietmar H.; Rojo, Fernando; Timmis, Kenneth N.; Knackmuss, Hans-JoachimThe simultaneous bacterial metabolism of chloro- and methylaromatics via ortho- or metapathway, normally results in incomplete degradation and death of the organisms. This is caused by misrouting of central intermediates. i.e. substituted catechols into unproductive pathways and suicide inactivation of the key enzyme of meta pathway, (catechol 2,3-dioxygenase). The meta pathway proved to be definitely unsuited for productive metabolism of chloroaromatics. Therefore two strategies were used for simultaneous degradation of mixtures of chloro- and methylaromatics via ortho pathways: Methyllactons or certain mixtures of chloro- and methylaromatics were used as enrichment substrates, yielding strains which metabolized these compounds almost exclusively via the desired pathway. Alternatively relevant enzymes from five different catabolic pathways of three distinct soil bacteria were combined in a patchwork fashion generating a functional ortho cleavage route for methylaromatics coexisting with the ortho cleavage pathway of chloroaromatics.Item Open Access Nonlinear control of an industrial distillation column by exact linearization(1989) Allgöwer, Frank; Sax, Antonius; Gilles, Ernst Dieter-Item Open Access Covering "Les Arènes de Nîmes" with an air-inflated fabric structure(1989) Bergermann, Rudolf; Sobek, WernerTogether with a team of architects, we started to develop and to design a structure which should cover the central part of the arena. The design yielded to a lightweight structure which is able to be installed within 21 days, designed to withstand a windspeed of 200 km/h and able to carry a snow load of 360 to - more than twice the deadweight of the new building. The air inflated cushion consists out of PVC-coated PETP-fabric membranes.Item Open Access Parametrisierte Speicherzellen zur Unterstützung des Selbsttests mit optimierten und konventionellen Zufallsmustern(1989) Kesel, Frank; Wunderlich, Hans-JoachimViele Selbsttestverfahren für hochintegrierte Schaltungen beruhen auf der Erzeugung von Zufallsmustem mit rückgekoppelten Schieberegistem. Oft wird jedoch für eine ausreichende Fehlererfassung eine unwirtschaftlich große Menge von Zufallsmustern benötigt, falls diese gleichverteilt erzeugt werden. Mit ungleichverteilten Zufallsmustern kann die Testlänge entscheidend reduziert werden, ein entsprechendes Selbsttestkonzept wurde als GURT (Generator of Unequiprobable Random Tests) vorgeschlagen. Im vorliegenden Beitrag werden Grundzellen zur Synthese von Registern nach dem GURT-Prinzip vorgestellt und die Probleme beim Entwurf eines entsprechenden Syntheseprogrammes diskutiert. Anhand eines Beispiels werden die Selbsttestkonzepte nach dem GURT- und nach dem BILBO-Prinzip verglichen.