94 research outputs found
Liesing in growth: an urban development concept for the transformation of the Wildschek area
No full textDer Fokus meiner Diplomarbeit liegt auf der städtebaulichen Entwicklung eines Quartiers in Wien-Liesing – dem Wildschek-Areal, das durch seine Identität bzw.Raumstruktur, Bebauungsstruktur sowie Freiraumverbindungselemente, ein wichtiges Subzentrum in Wien-Atzgersdorf wird.Das Gelände des Wildschek-Areals befindet sich zwischen Bahndamm und Breitenfurter Straße, nördlich der damaligen Sargfabrik.Das Areal umfasst 6 ha und war in der Vergangenheit eine private Parkanlage im Eigentum der Firma Ing. Egon Wildschek &Co, die ihre Produktion bis zum Jahr 2021 auf dem Grundstück durchgeführt hat.Liesing stellt den Übergangsraum vom dichtbebauten Zentrum zu südlichen Stadtteilen dar, mit einer fließenden Grenze. Der junge Bezirk bildet ein Portal in die Stadt aus dem Süden und wandelt sich in den letzten Jahren, nach seiner industriellen Vergangenheit, gleichzeitig in ein kreatives Baufeld.The City of Vienna has extraordinary qualities for its citizen and is therefore for many an ideal place to live and work. Liesing is one of the most dynamic urban development areas in Vienna,thanks to its high quality of life, its locationon the high-level subway and rail network.A post-industrial district with its land potential will experience strong population growth over the next ten years. To arrange this growth in a post-industrial sector a sustainable, comprehensible,and robust Quartier is needed. In addition to the planning of new infrastructure,it is also necessary to clarify and create an urban connection between existing and new. Urban planning accepts regularly new challenges. A modern Quartier accepts these challenges as well.Planning of a smart Quartier makes it possibleto establish an appropriate relationship between private and open spaces, to maintain the quality of life with an optimal density and to provide a smart city concept in any scale of housing. Inaddition, a Quartier creates appropriate connections between new and existing neighborhoods,encouraging them to cooperate at different levels
Comparison of optimization methodologies for robust feed-forward controller for gust load alleviation system
No full textThe master thesis work done by the author encompasses the design of a robust
feed-forward controller for gust load alleviation based on optimization techniques
to reduce the wing-box mass. The control methodology developed in this thesis
is independent of the aircraft platform and can be implemented any aircraft. The
author considers H2 and L00 norms in the cost function and synthesizes an optimal
feed-forward controller. The actuator limits (rate and deflection) and load factor
limits for passenger safety are included in the constraints of the optimization process.
The optimization process is carried out after determining the worst case load
scenario across the complete flight envelope and synthesizing the controller based on
that scenario so as to be robust for all fuel, mach and dynamic pressure variations.
The controller synthesized from the optimization process is transformed and reduced
to a lower order Infinite Impulse Response (IIR) filter from a higher order Finite
Impulse Response (FIR) filter. The IIR filter is further provided with a roll-off for
eliminating high frequency oscillations in the actuator. The robustness analysis is
carried out by performing Monte Carlo simulations for various parameter uncertainties.
The controller was synthesized on a linear model (longitudinal dynamics only)
with six elastic modes and it is validated on a linear model (longitudinal and lateral
dynamics) with nineteen elastic modes which includes non-linear actuators.Master of Science (Aerospace Engineering
Surface capture using near-real-time photogrammetry for a computer numerically controlled milling system
No full textDuring the past three years, a research project has been carried out in the Department of Mechanical Engineering at UCT, directed at developing a system to accurately reproduce three-dimensional (3D), sculptured surfaces on a three axis computer numerically controlled (CNC) milling machine. Sculptured surfaces are surfaces that cannot easily be represented mathematically. The project was divided into two parts: the development of an automatic noncontact 3D measuring system, and the development of a milling system capable of machining 30 sculptured surfaces (Back, 1988). The immediate need for such a system exists for the manufacture of medical prostheses. The writer undertook to investigate the measurement system, .with the objective to develop a non-contact measuring system that can be used to 'map' a sculptured surface so that it can be represented by a set of XYZ coordinates in the form required by the milling system developed by Back (1988). This thesis describes the development of a PC-based near-realtime photogrammetry system (PHOENICS) for surf ace capture. The topic is introduced by describing photogrammetric principles as used for non-contact measurements of objects. A number of different algorithms for image target detection, centering and matching is investigated. The approach to image matching adopted was the projection of a regular grid onto the surface with subsequent matching of conjugate grid intersections. A general algorithm which automatically detects crosses on a line and finds their accurate centres was developed. This algorithm was then extended from finding the crosses on a line, to finding all the intersection points of a grid. The algorithms were programmed in TRUE BASIC and specifically adapted for use with PHOENICS as an object point matching tool. The non-contact surface measuring technique which was developed was used in conjunction with the milling system developed by Back (1988) to replicate a test object. This test proved that the combined system is suitable for the manufacture of sculptured surf aces. The accuracy requirements for the manufacture of medical prostheses can be achieved with the combined measuring and milling system. At an object-to-camera distance of 0.5 m, points on a surface can be measured with an accuracy of approximately 0.3 mm at an interval of 5 mm. This corresponds to a relative accuracy of 1:1600. Back (1988) reported an average undercutting error of 0.46 mm for the milling system. This combines to an uncertainty of 0.55 mm. Finally, the limitations of PHOENICS at its prototype stage as a surface measuring tool are discussed, in particular the factors influencing the system's accuracy. PHOENICS is an ongoing project and the thesis is concluded by some recommendations for further research work
The interaction between active aeroelastic control and structural tailoring in aeroservoelastic wing design
No full textThis paper presents an analysis of the interaction and trade-off between active aeroelastic control and passive structural tailoring on a free-flying fully flexible aircraft model. Both technologies are included in the preliminary design of a typical transport aircraft configuration with a conventional control surface layout containing trailing edge control surfaces and spoilers. The passive structural tailoring is facilitated by exploiting the anisotropic properties of composite materials to steer the static and dynamic aeroelastic behaviour. Active aeroelastic control is implemented by scheduled control surface deflections redistributing the aerodynamic loads during manoeuvres to achieve manoeuvre load alleviation and a feed-forward control law for gust load alleviation. The panel-based aerodynamic modelling of spoiler deflections is improved by a correction of the spatial distribution of the boundary condition derived from higher fidelity simulation data. The optimisation of active control laws requires the consideration of constraints of the actuation system, namely rate and deflection saturation, in a nonlinear manner. The interaction of manoeuvre load alleviation, gust load alleviation and passive structural tailoring is investigated on the basis of results of different aeroservoelastic optimisations. Therefore the primary wing structure is simultaneously optimised with the individual technologies being activated or deactivated, resulting in eight different wing structures. The results of the individual and combined optimisations reveal significant design differences. The potentials of the different technologies can only be optimally exploited by simultaneous optimisation. The paper concludes with a study of the sensitivity of the major findings with respect to the knockdown factor for failure applied to the material properties. A substantial shift of effectiveness from active aeroelastic control to passive structural tailoring is observed with increased allowables resulting in more flexible and hence less stiff wing designs.Aerospace Structures & Computational Mechanic
Feasibility study of the CMS first-level muon trigger track finder
No full textWe describe a feasibility study for a fast, pipelined first-level muon trigger based on measurements from drift tube chambers for the CMS experiment at LHC. The algorithm, hardware implementation and simulation results for the performance are presented. (14 refs)
Flight Dynamics and Control Related Challenges for Design of a Commercial Blended Wing Body Aircraft
No full textFeasibility of the Hardware Muon Trigger Track Finder Processor in CMS
No full textThis paper describes a feasibility study for the design of the Muon Trigger Track Finder Processor in the high-energy physics experiment CMS (Compact Muon Solenoid, planned for 2005) at CERN. It covers the specification, proposed method, and a prototype implementation. Comparison between several other measurement methods and the proposed one are carried out. The task of the processor is to identify muons and measure their transverse momenta and locations within 350 ns. It uses data from almost two hundred thousand detector cells of drift tube muon chambers. The processor searches for muon tracks originating from the interaction point by joining the track segments provided by the drift tube muon chamber electronics to full tracks. It assigns transverse momentum to each reconstructed track using the track's bend angle
Concurrent Optimization of a Feed-Forward Gust Loads Controller and Minimization of Wing Box Structural Mass on an Aircraft with Active Winglets
No full textTrack finding processor in the DTBX based CMS barrel muon trigger
No full textWe present the design and simulation of the track finding processor in the DTBX ( Drift Tube with Bunch Crossing Identification) based CMS barrel muon trigger system. The processor searches for muon tracks originating from the interaction region by joining the track segments provided by the mean timer processors of the drift chambers to track strings. It assigns transverse momenta to the reconstructed tracks using the tracks' bending angle. High speed is achieved by performing the track reconstruction fully in parallel. In this contribution the algorithms, implementation and simulation results are presented
The Track Finder of the CMS First Level Muon Trigger
No full textThe track finder receives trigger primitives from drift tubes in the barrel and from cathode strip chambers in the endcap muon system. It assembles those trigger primitives to tracks, assigns transverse momentum, direction and quality to tracks and transmits these data to the global muon trigger. We present the track finder algorithm, hardware implementation and the status of the FPGA prototype
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