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In order to master the growing complexity of analogue electronic systems, modelling and simulation of analogue hardware at various levels is absolutely necessary. This paper presents an original modelling method based on the graphical description of analogue electronic functional blocks. This method is intended to be automated and integrated into a design framework: specialists create behavioural models of existing functional blocks, that can then be used through high-level selection and specification. Applications of behavioural modelling are discussed. >

The magneto-static behaviour of soft magnetic composites (SMCs) is investigated using tomography based direct numerical simulation. The microgeometry crucially affects the magnetic properties of the composite since a geometry dependent demagnetizing field is established inside the composite, which lowers the magnetic permeability. We determine the magnetic field information inside the SMC using direct numerical simulation of the magnetic field based on high resolution micro-computed tomography data of the SMC's microstructure as well as artificially generated data made of statistically homogeneous systems of identical fully penetrable spheres and prolate spheroids. Quasi-static electromagnetic behaviour and linear material response are assumed. The 3D magnetostatic Maxwell equations are solved using Whitney finite elements. Simulations show that clustering and percolation behaviour determine the demagnetizing factor of SMCs rather than the particle shape. The demagnetizing factor correlates with the slope of a 2-point probability function at its origin, which is related to the specific surface area of the SMC. Comparison with experimental results indicates that the relatively low permeability of SMCs cannot be explained by demagnetizing effects alone and suggests that the permeability of SMC particles has to be orders of magnitude smaller than the bulk permeability of the particle material.

This paper presents a pragmatic solution for the hardware-software cosimulation of microsystems. It allows a user to coverify a microsystem made up of custom digital electronics, processing cores and software. It can also be extended to the cosimulation of mixed-mode (analogue-digital) systems as well as mixed-nature (e.g., electrical-mechanical) systems. The custom hardware is described in VHDL. The software is developed in a dedicated environment and then translated into VHDL for simulation. The processor is described in VHDL as an Instruction Set Simulator (ISS) able to execute the software. A single tool, a VHDL simulator, is used to simulate the whole system. Its graphical user interface has been extended with a new software debug window. The approach has been demonstrated for Microchip’s PIC16C5X microcontroller family.

In this paper we make use of a mixed analogue-digital HDL to model sampled-data systems. Modelling solutions are presented to code some sampled-data behaviour using either analogue or digital constructs of the language.

In this chapter, we present the computer-aided analogue behavioural modelling tool ABSynth (Analogue Behavioural model Synthesizer). The behaviour to model is expressed graphically in the form of a Functional Diagram (FD) drawn as the interconnection of Graphical Building Symbols (GBS), each of which stands for some elementary analogue behaviour. The functional diagram describes the behaviour of the system only, not its physical structure. The corresponding HDL-A™ code is then generated automatically.

Der Zweck einer Verdichtung von Boden ist die Verbesserung ihrer Eigenschaften, wie z. B. die Verminderung der Setzungsempfindlichkeit, die Erhohung der Scherfestigkeit, die Verminderung der Durchlassigkeit usw. Gleichzeitig kann die Verdichtung, zweckentsprechend ausgefuhrt, den Boden „homogenisieren“, d. h. seine Eigenschaften, wie z. B. die Lagerungsdichte usw., gleichmasiger gestalten. In vielen Fallen kommt es weniger auf die absoluten Kennziffern an, sondern vielmehr auf die Homogenitat innerhalb eines bestimmten Teilstuckes. Die Homogenisierung wird so zum eigenstandigen Ziel der Verdichtung.

Die bisherigen Abschnitte dieses Buches beziehen sich auf die Eigenschaften von Boden bzw. auf die darin erfolgenden bautechnischen Eingriffe. Geologisch werden Boden als Lockergesteine bezeichnet. Sie entstehen aus Festgestein (Fels) durch Zerscherung und/oder Verwitterung und sind meist nach dem Transport im Wasser sedimentiert. Im Flachland und an Hangen ist der felsige Untergrund haufig von Boden uberdeckt. Nicht selten werden in tiefen Baugruben Boden und Fels angeschnitten oder z. B. beim Auffahren eines Tunnels gleichzeitig oder nacheinander durchfahren (Bild 16.1). In den Bergen erfolgen Hangrutschungen haufig auf der in geringer Tiefe anstehenden Felsoberflache. Oft sind die Ubergange zwischen Boden und Fels (Molasse) fliessend, d. h. nicht genau definierbar. Bei aufgewittertem Fels sprechen wir von „soft rock“ oder bei verfestigtem Boden von „hard soil“.

Die Festigkeit eines Bodens bezeichnen wir als Scherfestigkeit. Sie nimmt eine zentrale Stellung unter den Bodeneigenschaften ein, da sie fur alle Stabilitatsprobleme (Kapitel 9 und 13) wie Boschungsstabilitat, Tragfahigkeit, Erddruck u. a. die masgebende Grose ist. Um die Scherfestigkeit zu beschreiben, ist ein Bruchkriterium notwendig, mit dessen Hilfe die Ergebnisse von experimentellen Untersuchungen der Scherfestigkeit ausgewertet und dargestellt werden konnen. Das Kriterium soll moglichst einfach sein und die Beziehungen der Hauptspannungen untereinander im Grenzgleichgewicht (Bruchzustand) eines Bodenelementes wiedergeben. Die Parameter, die den Bruchzustand umschreiben, sollen gut experimentell bestimmbar und einfach sein, und sollen die Grundlage fur die Untersuchung aller Stabilitatsprobleme bilden.

In Abschnitt 1.6 wurde der Durchlassigkeitskoeffizient k, kurz k-Wert genannt, definiert. Er ist ein Mas fur den Widerstand, den das stromende Wasser im Boden erfahrt. Um den vollstandigen hydraulischen Zustand eines durchstromten Bodenprofils zu erfassen, mussen in jedem Punkt das Potential H sowie die k-Werte in allen Richtungen bekannt sein. Ist diese Voraussetzung erfullt, so lassen sich alle Fragen nach Druckverhaltnissen in beliebigen Punkten oder nach durchstromenden Wassermengen durch die Losung der Differentialgleichung der Grundwasserstromung beantworten, z. B. durch die Konstruktion eines Stromungsnetzes. Da die oben erwahnte Bedingung oft nicht erfullbar ist, werden in der Praxis haufig vereinfachte Annahmen herangezogen, wobei sich Extremalannahmen oftmals als hilfreich erweisen.

This paper describes a powerful inexact matching algorithms which has been applied with success to high-level 3D object representations in a 3D object recognition system. The algorithm combines in a promising way several approaches proposed in the past couple of years: an extension to the backtrack strategies for inexact matching of attributed relational sub- graphs, error correction isomorphism, determination of local attribute similarity, and global transformation fitting, features which are efficiently used for search-tree pruning. The algorithm was tested successfully in a series of experiments involving scenes with single and multiple objects.

The Oxidation of Two New 1,3-Dihydroxyimidazolidines – Synthesis and Structure of Nitronyl Nitroxide Radicals The two new 1,3-dihydroxyimidazolidines 3a and 3b were prepared by condensation of 4-formylbenzoic acid (2a) and sodium glyoxylate (2b) with 2,3-dimethyl-2,3-butanediylbis-(hydroxylamine) sulfate (1). The 1,3-dihydroxyimidazolidines were oxidized with sodium periodate in water to form nitronyl nitroxide radicals. Oxidation of the 1,3-dihydroxyimidazolidine 3a yielded the new radical 4a, whereas the product obtained from the 1,3-dihydroxyimidazolidine 3b was, due to decarboxylation, the unsubstituted radical 4c. The crystal structure of 4a was solved by single-crystal X-ray diffraction, showing the molecules to be arranged in zigzag chains as a consequence of intermolecular hydrogen bonds.

Na10[CoO3]{[CoO3](OH)2} wurde durch Redoxreaktion zwischen metallischem Cobalt und CdO in Anwesenheit von NaOH und Na2O bei 600 °C (21 d) in Form roter Einkristalle erhalten. Die Kristallstruktur wurde anhand von Einkristalldaten bestimmt (IPDS-Daten, Pnma, Z = 4, a = 988, 5(1) pm, b = 1013, 9(2) pm, c = 1186, 3(2) pm, wR2 = 0, 079). Weiterhin werden schwingungsspektroskopische Ergebnisse und Betrachtungen zum Madelung-Anteil der Gitterenergie prasentiert. A Sodium-Oxocobaltate(II)-Hydroxide: Na5[CoO3]OH ≡ Na10[CoO3]{[CoO3](OH)2} Na10[CoO3]{[CoO3](OH)2} has been obtained from a redox reaction between cobalt metal and CdO in the presence of NaOH and Na2O at 600 °C (21 d) as red single crystals. The structure has been determined from single crystal data (IPDS-data, Pnma, Z = 4, a = 988.5(1) pm, b = 1013.9(2) pm, c = 1186.3(2) pm, wR2 = 0.079). Furthermore IR data and aspects of the Madelung part of the lattice energy are presented.

Na9[FeO3][FeO4]a Mixed Valent Oxoferrat(II, III) with Isolated [FeO3]4— — and [FeO4]5— Anions Na9[FeO3][FeO4] has been formed and obtained from a redox reaction between CdO and iron metal (reaction container) and Na2O in the presence of NaOH at 450 °C as orange-red transparent single crystals. The crystal structure determination (IPDS data: Pca21, a = 956.2(2) pm, b = 999.1(2) pm, c = 1032.3(2) pm, Z = 4, Rall = 0.0455) reveals the presence of isolated complex anions, [FeO3]4— and [FeO4]5—.

Any historian who deals with a period in which conspirators played a significant role sooner or later comes up against the conspirator's twin brother, the undercover police agent. In most cases, the policeman revolutionary or revolutionary policeman, however fascinating as an entrée into the twilight world of double and triple agents, offers more to the enterprising journalist than to the historian. Even some of the more spectacular exemplars of real or reputed undercover agents – Roman Malinovsky, who rose to membership in the central committee of the Bolshevik party before 1917; Lucien Delahodde, who until his exposure was a leading light in the secret societies of the July Monarchy; Auguste Blanqui, the unquenchable revolutionary who may or may not have informed on his comrades in 1839 – did not really affect the general course of history, at least not as informers. Though Malinovsky as a psychological phenomenon cries out for a latter-day Dostoevsky, his amazing career did not in any way deflect the Bolsheviks from their goal. Delahodde's more businesslike relations with the Orleanist police sapped an underground republican movement which was already impotent and discredited before he joined it. In Blanqui's case, the question of guilt or innocence is almost irrelevant, though the accusation of treason which the journalist Taschereau levelled in March 1848 did foil Blanqui's efforts to lead the left-wing opposition to the Provisional Government.

Some years ago in the pages of this journal I published an article that tried to solve the problem of whether the June 1848 insurrection was organized or spontaneous by focusing on the campaign for a monster "Banquet of the People, Fraternization of the Workers," which attracted widespread attention just prior to the outbreak.' My findings indicated a striking contrast between the attitudes of a militant rank and file, enthusiastically welcoming a mass gathering of the Paris workers, and those of a club leadership, anxious to avoid trouble in the belief that the working class would become the first victim of violence By implication, I construed the clubs' sabotage of the potentially insurrectionary banquet as circumstantial evidence that the June insurrection was indeed a spontaneous outburst in which the radical leaders played at best the part of reluctant followers. The justification for this somewhat roundabout approach to the motives and outlook of the insurgents was the seeming lack of direct evidence. My documentation was based on a perusal of much of the left-wing press, supplemented by some unpublished police reports and other documents from the archives of the parliamentary commission that investigated the causes of the June uprising.2 The aim of this note is to set the record straight on the basis of new evidence, while using this opportunity to draw the attention of