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Siedlungswasserwirtschaft
(2012)
Die bauaufsichtliche Einführung der Eurocodes steht unmittelbar bevor. Für den Bereich des Stahl- und Spannbetonbaus soll die Anwendung zum 1. Juli 2012 verbindlich sein, d. h. mit diesem Stichtag sollte nur noch der Eurocode 2 (DIN EN 1992-1-1, Ausgabe Januar 2011) mit seinem zugehörigen nationalen Anhang (DIN EN 1992-1-1/NA, Ausgabe Januar 2011) Verwendung finden, die DIN 1045-1 wird zurückgezogen. Bereits seit März 2010 gilt eine Übergangsphase, ist der die Anwendung des Eurocodes alternativ zur DIN 1045-1 als bauaufsichtlich gleichwertige Lösung möglich.
Styling
(2008)
Modell
(2008)
Skizze
(2008)
The technology programme “Reduction of aerodynamic drag (RaWid)” for high speed aerodynamics at Daimler-Benz Aerospace Airbus is sponsered by the German ministry for education, research and technology since July 1, 1995. Connected to this industrial programme are the cooperation programmes “MEGAFLOW” under leadership of the DLR and “Transition” by the DFG, and several contributions by DLR and universities.
The programme is oriented towards technologies required for a MEGALINER which gains momentum by the ambitious plans for a new large Airbus A3XX.
In the first year new technological steps were undertaken in theory, design and experiment. Some critical steps were verified by wing designs checked in wind tunnel tests.
This work describes a procedure to yield attenuation maps from MR images which are used for the absorption correction (AC) of brain PET data. Such an approach could be mandatory for future combined PET and MRI scanners, which probably do not include a transmission facility. T1-weighted MR images were segmented into brain tissue, bone, soft tissue, and sinus; attenuation coefficients corresponding to elemental composition and density as well as to 511 keV photon energy were respectively assigned. Attenuation maps containing up to four compartments were created and forward projected into sinograms with attenuation factors which then were used for AC during reconstruction of FDG-PET data. The commonly used AC based on a radioactive (68Ge) transmission scan served as reference. The reconstructed radioactivity values obtained with the MRI-based AC were about 20% lower than those obtained with PET-based AC if the skull was not taken into account. Considering the skull the difference was still about 10%. Our investigations demonstrate the feasibility of a MRI-based AC, but revealed also the necessity of a satisfying delineation of bone thickness which tends to be underestimated in our first approach of T1-weighted MR image segmentation.
Today the most accurate and cost effective industrial codes used in aircraft design are based on the full potential equation coupled with boundary layer equations. However, these are not capable to solve complicated three-dimensional problems of vortical flows and shocks. On the other hand Euler and Navier-Stokes codes are too expensive and not accurate enough for design purposes, especially in regard of drag and interference prediction. The reasons for these deficiencies are investigated and a way to overcome them by future developments is demonstrated.
In the preceeding chapters on “Son of Concorde, a Technology Challenge” and “Aerodynamic Multipoint Design Challenge” it was explained, that a well balanced contribution of new technologies in all major disciplines is required for realisation of a new Supersonic Commercial Transport (SCT). One of these technologies - usually one of the most important for aircraft-is aerodynamics. Here, the required “pure” aerodynamic technologies are specified in more detail, according to our present knowledge. Increasing insight into the problems may change the balance of importance of the individual technologies and may require some more contributions. We must never confine our knowledge to the knowledge base of an expert at a given time, but must stay open for new insights.
Since certification of Concorde new certification standards were introduced including many new regulations to improve flight safety. Most of these standards are to prevent severe accidents in the future which happened in the past (here: after Concorde’s certification). A new SCT has to fulfill these standards, although Concorde had none of these accidents. But accidents - although they sometimes occurred only for a specific aircraft type - have to be avoided for any (new) aircraft. Because of existing aircraft without typical accident types having demonstrated their reliability, they are allowed to go on based on their old certification; although sometimes new rules prevent accident types which are not connected to specific aircraft types - like e.g. evacuation rules. Anyway, Concorde is allowed to fly based on its old certification, and hopefully in the future will fly as safely as in the past. But a new SCT has to fulfill updated rules like any other aircraft, and it has to be “just another aircraft” [75].
Supersonic laminar flow
(1997)
Supersonic transports are very drag sensitive. Technology to reduce drag by application of laminar flow, therefore, will be important; it is a prerequisite to achieve very long range capability. In earlier studies it was assumed that SCTs would only become possible by application of laminar flow [376]. But today, we request an SCT to be viable without application of laminar flow in order to maintain its competitiveness when laminar flow becomes available for subsonic and supersonic transports. By reducing fuel burned, laminar flow drag reduction reduces size and weight of the aircraft, or increases range capability -whereas otherwise size and weight would grow towards infinity. Transition mechanisms from laminar to turbulent state of the boundary layer flow (ALT, CFI, TSI) function as for transonic transports, but at more severe conditions: higher sweep angles, cooled surfaces; higher mode instabilities (HMI) must at least be taken into account, although they may not become important below Mach 3. Hitherto there is a worldwide lack of ground test facilities to investigate TSI at the expected cruise Mach numbers between 1.6 and 2.4; in Stuttgart, Germany one such facility -a Ludwieg tube- is still in the validation phase. A quiet Ludwieg tunnel could be a favourable choice for Europe. But it will require a new approach in designing aircraft which includes improved theoretical predictions, usage of classical wind tunnels for turbulent flow and flight tests for validation.
Concorde (Figure 9) is the only supersonic airliner which has been introduced into regular passenger service. It is still in service at British Airways and Air France without any flight accidents, and probably will stay in service for at least for ten more years.
In the chapter “Son of Concorde, a Technology Challenge” one of the new challenges for a Supersonic Commercial Transport (SCT) is multi-point design for the four main design points:
- supersonic cruise
- transonic cruise
- take-off and landing
- transonic acceleration.
It has been observed that carcinogenic polycyclic aromatic hydrocarbons (PAH) are present in the atmosphere. Combustion processes are considered the most important sources for PAH. Among these, the burning of coal produces the highest emission, but in cities with high traffic density and low meteorological exchange activities, vehicle emissions determine the immission situation, especially in narrow streets. For estimating the potential health effects caused by PAH, it is sufficient to characterize the emission of PAH with respect to their physical state, concentrations, and, as far as the particulate phase is concerned, size distribution. The size distribution is important for transport phenomena, inhalation, and deposition in the respiratory tract. These parameters mainly depend on the combustion system, on system operating conditions, on the exhaust system, and on exhaust cooling conditions. At exhaust-gas temperatures in the range of ambient air temperatures, almost the whole emission of PAH is made up of particulate matter.
Abfallwirtschaft
(1998)
Abfallwirtschaft
(2005)
Inhaltsverzeichnis:
I. Lern- und Arbeitstechniken im 1. und im 10. Semester
II. Lern- und Arbeitstechniken als persönliches Selbstmanagement
III. Diskussionsfragen und -thesen
IV. Was heißt: Eigenverantwortung im Studium?
V. Eigenverantwortung als gelebte Freiheit von Studierenden
VI. Warum es unmöglich ist, Verantwortung an Studierende zu delegieren VII. Erziehungsauftrag: Studierende in ihrer Eigenverantwortung belassen VIII. Folgerungen für Lehrende IX. Folgerungen für Studierende
Bei der Beschreibung der Studiengänge und Module durch die Hochschulen kommt der Ergebnisorientierung eine hohe Bedeutung zu. Der Beitrag beschreibt in diesem Zusammenhang zunächst die Vorgaben des europäischen Qualifikationsrahmens und der sich daraus ergebenden Fokussierung auf die Formulierung von Lernergebnissen. Der Schwerpunkt aber liegt auf praxisrelevanten Vorschlägen zu einem methodischen Vorgehen auf allen Ebenen von der Studiengangsbeschreibung über die Verteilung der Kompetenzarten über mehrere Module bis zur Wortwahl. Abschließend wird die an die Wahl der Lehr- und Lernformen geknüpfte Notwendigkeit der Veränderung der Prüfungsformen betont. Diese sollten inhaltlich und methodisch an die in den Studiengängen und Modulen beschriebenen Lernergebnisse und die Art der zu vermittelnden Kompetenzen angepasst werden. Vorabdruck des Aufsatzes. Erschienen in: Handbuch Qualität in Studium und Lehre : Evaluation nutzen, Akkreditierung sichern, Profil schärfen ( Hrsg. Winfried Benz ... . Berlin: Raabe Kapitel E 3.3 S. 1-30. ISBN 978-3-8183-0207-8 ; 3-8183-0207-3 1. Auflage des Aufsatzes unter dem Titel: Lernergebnisse - Begriffe, Zusammenhänge, Umsetzung und Erfolgsermittlung : Lernergebnisse und Kompetenzvermittlung als elementare Orientierungen des Bologna-Prozesses http://opus.bibliothek.fh-aachen.de/opus/volltexte/2007/232/
zuerst erschienen In: Handbuch Qualität in Studium und Lehre : Evaluation nutzen, Akkreditierung sichern, Profil schärfen / Hrsg.: Winfried Benz .... Berlin: Raabe ISBN 978-3-8183-0207-8 ; 3-8183-0207-3 , Kapitel E.3.3 S. 1-30 Sonderdruck unter dem Titel: Schermutzki, Lernergebnisse - Begriffe, Zusammenhänge, Umsetzung und Erfolgsermittlung. Fachhochschule Aachen, 2007. 39 S.: graph. Darst. Der Beitrag beschreibt die Bedeutung und Notwendigkeit der Verwendung von Lernergebnissen als gemeinsame Sprache zwischen den verschiedenen Hochschulen und zwischen Hochschule und beruflicher Bildung, um zu einem feststellenden Validitätsurteil und zu funktionstüchtigen Anerkennungsmechanismen zu kommen. Hierbei kommt der ergebnisorientierten Beschreibung der Studiengänge und Module durch die Hochschulen große Bedeutung zu. Der Beitrag beschreibt die diesbezüglichen Grundlagen und schlägt Methoden vor, die bei der praktischen Beschreibung, der Wahl der Lehr- und Lernformen und Prüfungsformen von Studiengängen und Modulen angewendet werden können.