Zur Eröffnung der elektrischen Hoch- und Untergrundbahn in Berlin

ZUR ERÖFFNUNG DER ELEKTRISCHEN HOCH- UND UNTERGRUNDBAHN IN BERLIN Zur Eröffnung der elektrischen Hoch- und Untergrundbahn in Berlin / Kemmann, Gustav (Public Domain) ( - ) Photograph: Gleisdreieck der elektrischen Hoch- und Untergrundbahn in Berlin ( - ) Title page ( - ) Contents ( - ) Allgemeine Uebersicht ( - ) Photograph: Gebäudegruppe Ecke Tempelhofer Ufer und Trebbiner Strasse mit der Hochbahneinfahrt und dem Kraftwerk. Architekt: Reg.-Baumeister P. Wittig ( - ) Zur Eröffnung der elektrischen Hoch- und Untergrundbahn in Berlin ([9]) A. Aenderungen an dem ursprünglichen Entwurf, welche die Linienführung betreffen ([9]) B. Architektonische Durchbildung der Hochbahn (15) Photograph: Architektonische Ausbildung der Viaduktportale am Sedanufer[.] Ansicht von Nordwesten. Architekt: Professor Grenander ; Hochbahnviadukt zwischen Potsdamer Strasse und Nollendorfplatz (17) Photograph: Architektonische Ausbildung der Hochbahnbrücke über den Landwehrkanal[.] Ansicht von Osten. Architekt: Regierungsbaumeister Wittig ; Bahnhof Stralauer Thor[.] Ansicht von Süden. Architekt: Regierungsmeiser Necker (20) Photograph: Bahnhof Bülow-Strasse. Architekt: Möhring ; Bahnhof Nollendorf-Platz. Architekten: Cremer und Wollfenstein ( - ) C. Betriebsanlagen der Hochbahn (26) Photograph: Innereres eines Wagens II. Klasse ; Innereres eines Wagens III. Klasse ; (31) Illustration: Schema des Fahrplans der Hoch- und Untergrundbahn (31) Photograph: Kessel- und Maschinenraum der elektrischen Hoch- und Untergrundbahn ( - ) Illustration: Züge, Zugbetrieb und Abfertigungsweise der Züge (33) D. Einzelheiten über die Bauausführung der Untergrundstrecken (45) E. Schlussbemerkungen (53) Elektrische Hoch- und Untergrundbahn in Berlin ( - ) ColorChart ( -

Hydrodynamic behavior in expanding thermal clouds of Rb-87

We study hydrodynamic behavior in expanding thermal clouds of Rb-87 released from an elongated trap. At our highest densities the mean free path is smaller than the radial size of the cloud. After release the clouds expand anisotropically. The cloud temperature drops by as much as 30%. This is attributed to isentropic cooling during the early stages of the expansion. We present an analytical model to describe the expansion and to estimate the cooling. Important consequences for time-of-flight thermometry are discussed.Comment: 7 pages with 2 figure

SAHARA - A Structured Approach for Hazard Analysis and Risk Assessments

In this thesis, an approach is presented that turns the currently unstructured process of automotive hazard analysis and risk assessments (HRA), which relies on creativity techniques, into a structured, model-based approach that makes the HRA results less dependent on experts' experience, more consistent, and gives them higher quality. The challenge can be subdivided into two steps. The first step is to improve the HRA as it is performed in current practice. The second step is to go beyond the current practice and consider not only single service failures as relevant hazards, but also multiple service failures. For the first step, the most important aspect is to formalize the operational situation of the system and to determine its likelihood. Current approaches use natural-language textual descriptions, which makes it hard to ensure consistency and increase efficiency through reuse. Furthermore, due to ambiguity in natural language, it is difficult to ensure consistent likelihood estimates for situations. The main aspect of the second step is that considering multiple service failures as hazards implies that one needs to analyze an exponential number of hazards. Due to the fact that hazard assessments are currently done purely manually, considering multiple service failures is not possible. The only way to approach this challenge is to formalize the HRA and make extensive use of automation support. In SAHARA we handle these challenges by first introducing a model-based representation of an HRA with GOBI. Based on this, we formalized the representation of operational situations and their likelihood assessment in OASIS and HEAT, respectively. We show that more consistent situation assessments are possible and that situations (including their likelihood) can be efficiently reused. The second aspect, coping with multiple service failures, is addressed in ARID. We show that using our tool-supported HRA approach, 100% coverage of all possible hazards (including multiple service failures) can be achieved by relying on very limited manual effort. We furthermore show that not considering multiple service failures results in insufficient safety goals

Untersuchungen zum Fuellverhalten von mikrostrukturierten Formteilen beim Mikrospritzgiessen von Polymerschmelzen

The use of injection moulding for micro technology products is increasing steadily due to its economical and technical importance. A lot of products for medical, telecommunication or biotechnology applications require high precision combined with low production costs. LIGA technology allows the production of moulds for parts with sub millimetre precision. Micro injection moulding combines high automation and the processing of engineering polymers. Within this research the process of filling micro structured parts is investigated. Micro structured parts are parts with regular injection moulding size containing sections on the part which are structured in the sub-millimetre range. Further on software tools for the simulation of the filling process are used and investigated to evaluate the usability of such tools for micro injection moulding. This results lead to the definition of new specifications for simulation tools. (orig.)SIGLEAvailable from TIB Hannover: RA 5476(19) / FIZ - Fachinformationszzentrum Karlsruhe / TIB - Technische InformationsbibliothekDEGerman

An Experimental Investigation of Combined Symmetric Asymmetric Composite Laminates

It has been found that certain asymmetric composite laminates exhibit bistability, and are thus called bistable composite laminates. A bistable composite laminate is a composite laminate that exhibits multiple stable static equilibrium states. If the bistable composite is actuated it will snap to its secondary equilibrium state and then remain there without any further actuation. This unique behavior of bistable composites has made them the subject of much research in the areas of morphing structures as well as energy harvesting. Much of the research done on bistable laminates has been focused on the fundamental characterization of the bistable behavior and of the laminate equilibrium shapes. Little investigation has been done on how the boundary conditions affect the bistable behavior and this study investigates how the amount of symmetry in a partially- symmetric partially-asymmetric rectangular laminate under an imposed clamped edge boundary condition affects the bi-stability and the curvature of the laminate. A simple design of experiment was developed and 5 sets of 41 laminates with varying amounts of asymmetry were fabricated. These laminates were measured using a profilometer to capture the post cure and snap through curvatures of the laminates with a fixed edge boundary condition. The results showed that up to 20% symmetry can be introduced in the laminate without a substantial loss in snap through curvature, and that up to 83% symmetry can be introduced in the laminate before bistability is lost. Finite element simulations were conducted in Abaqus CAE 6.14 and the results showed good correlation with the experimental results