279,260 research outputs found

    Driving Cars by Means of Genetic Algorithms

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    Proceedings of: 10th International Conference on Parallel Problem Solving From Nature, PPSN 2008. Dortmund, Germany, September 13-17, 2008The techniques and the technologies supporting Automatic Vehicle Guidance are an important issue. Automobile manufacturers view automatic driving as a very interesting product with motivating key features which allow improvement of the safety of the car, reducing emission or fuel consumption or optimizing driver comfort during long journeys. Car racing is an active research field where new advances in aerodynamics, consumption and engine power are critical each season. Our proposal is to research how evolutionary computation techniques can help in this field. As a first goal we want to automatically learn to drive, by means of genetic algorithms, optimizing lap times while driving through three different circuits.Publicad

    Cathodic and Anodic Material Diffusion in Polymer/Semiconductor-Nanocrystal Composite Devices

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    In the present day, the information technologies and telecommunications sector continually increase their demand for low cost, low power consumption, high performance electroluminescent devices for display applications. Furthermore, general lighting applications, such as white light and large array colour displays, would also benefit from an increase in the overall efficiency. Several technologies are being investigated to fulfill these needs, such as organic light emitting diodes (OLED), polymeric light emitting diodes (PLED) and field effect emission devices. A new and promising technology is light emitting devices (LEDs) based on nanostructured materials. With organic LEDs (OLEDs) already making an impact on the market in an increasingly large number of applications, hybrid technologies based on organic/inorganic nano-composites are a potential the next step. The incorporation of highefficiency fluorescent semiconductor nanoparticles has been shown to have a beneficial effect on device performance, [1] modify the colour output from the device 2 and provide a simplified route to generation of LED type devices. [3

    The impact of the EU ETS on the sectoral innovation system for power generation technologies: findings for Germany

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    This paper provides an overview of early changes in the sectoral innovation system for power generation technologies which have been triggered by the European Emission Trading Scheme (EU ETS). Based on a broad definition of the sector, our research analyses the impact of the EU ETS on the four building blocks knowledge and technologies, actors and networks, institutions and demand by combining two streams of literature, namely systems of innovation and environmental economics. Our analysis is based on 42 exploratory inter-views with German and European experts in the field of the EU ETS, the power sector and technological innovation. We find that the EU ETS mainly affects the rate and direction of the technological change of power generation technologies within the large-scale, coal-based power generation technological regime to which carbon capture technologies are added as a new technological trajectory. While this impact can be interpreted as defensive behaviour of incumbents, the observed changes should not be underestimated. We argue that the EU ETS' impact on corporate CO2 culture and routines may prepare the ground for the transition to a low carbon sectoral innovation system for power generation tech-nologies. --EU emission trading scheme (EU ETS),innovation system,power sector

    Evolving a rule system controller for automatic driving in a car racing competition

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    IEEE Symposium on Computational Intelligence and Games. Perth, Australia, 15-18 December 2008.The techniques and the technologies supporting Automatic Vehicle Guidance are important issues. Automobile manufacturers view automatic driving as a very interesting product with motivating key features which allow improvement of the car safety, reduction in emission or fuel consumption or optimization of driver comfort during long journeys. Car racing is an active research field where new advances in aerodynamics, consumption and engine power are critical each season. Our proposal is to research how evolutionary computation techniques can help in this field. For this work we have designed an automatic controller that learns rules with a genetic algorithm. This paper is a report of the results obtained by this controller during the car racing competition held in Hong Kong during the IEEE World Congress on Computational Intelligence (WCCI 2008).Publicad

    The Commensal Real-time ASKAP Fast Transients (CRAFT) survey

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    We are developing a purely commensal survey experiment for fast (<5s) transient radio sources. Short-timescale transients are associated with the most energetic and brightest single events in the Universe. Our objective is to cover the enormous volume of transients parameter space made available by ASKAP, with an unprecedented combination of sensitivity and field of view. Fast timescale transients open new vistas on the physics of high brightness temperature emission, extreme states of matter and the physics of strong gravitational fields. In addition, the detection of extragalactic objects affords us an entirely new and extremely sensitive probe on the huge reservoir of baryons present in the IGM. We outline here our approach to the considerable challenge involved in detecting fast transients, particularly the development of hardware fast enough to dedisperse and search the ASKAP data stream at or near real-time rates. Through CRAFT, ASKAP will provide the testbed of many of the key technologies and survey modes proposed for high time resolution science with the SKA.Comment: accepted for publication in PAS

    Near-monochromatic tuneable cryogenic niobium electron field emitter

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    Creating, manipulating, and detecting coherent electrons is at the heart of future quantum microscopy and spectroscopy technologies. Leveraging and specifically altering the quantum features of an electron beam source at low temperatures can enhance its emission properties. Here, we describe electron field emission from a monocrystalline, superconducting niobium nanotip at a temperature of 5.9 K. The emitted electron energy spectrum reveals an ultra-narrow distribution down to 16 meV due to tunable resonant tunneling field emission via localized band states at a nano-protrusion's apex and a cut-off at the sharp low-temperature Fermi-edge. This is an order of magnitude lower than for conventional field emission electron sources. The self-focusing geometry of the tip leads to emission in an angle of 3.7 deg, a reduced brightness of 3.8 x 10exp8 A/(m2 sr V), and a stability of hours at 4.1 nA beam current and 69 meV energy width. This source will decrease the impact of lens aberration and enable new modes in low-energy electron microscopy, electron energy loss spectroscopy, and high-resolution vibrational spectroscopy.Comment: to be published in Phys. Rev. Lett. (2022

    PCA Tomography and its application to nearby galactic nuclei

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    With the development of modern technologies such as IFUs, it is possible to obtain data cubes in which one produces images with spectral resolution. To extract information from them can be quite complex, and hence the development of new methods of data analysis is desirable. We briefly describe a method of analysis of data cubes (data from single field observations, containing two spatial and one spectral dimension) that uses Principal Component Analysis (PCA) to express the data in the form of reduced dimensionality, facilitating efficient information extraction from very large data sets. We applied the method, for illustration purpose, to the central region of the low ionization nuclear emission region (LINER) galaxy NGC 4736, and demonstrate that it has a type 1 active nucleus, not known before. Furthermore, we show that it is displaced from the centre of its stellar bulge.Comment: 4 pages, 1 figure, 1 table, to be published in the Proceedings of the IAU Symposium no. 26

    Technological Perspective for Reducing Emissions from Marine Engines

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    Climate change and adverse impacts on the ocean environment have recently received much attention in the shipping and marine economic sectors. Preventing pollution of the marine environment from land sources through the river or atmospheric water is only possible by applying clean industrial technologies without waste and methods for rational use of natural resources. Main technical facilities to protect the sea environment from the current pollution are used to remove toxic substances from waste sources of ships. The International Maritime Organization increasingly tightens regulations on emissions with marine transport fleets, especially emissions of NOx and SOx. Therefore, many countries in the world continually improve and develop marine diesel engines in the direction of reducing emissions with different technologies. It is a tremendous necessary to enrich the technological knowledge to select new energy equipment in shipbuilding because they play a vital role in ensuring emission standards throughout the life of the ship. Indeed, technology development orientation in coastal countries' marine industry with the initial study results on the use of extraction optimization measures, alternative fuels, and output emission control solutions, it shows that we can implement some technologies to achieve NOx and SOx reduction according to IMO regulations. This paper summarizes the most important recent development technologies in the world in the field of marine engines. Also, the authors assessed the possibility of applying these new technologies to fleets of coastal countries to meet environmental requirements

    New PET technologies:performance, image quality, and clinical implications

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    The most specific and sensitive imaging modality for visualizing and measuring human (patho)physiology in vivo is Positron Emission Tomography (PET). PET is a firmly established biomedical imaging modality with applications in routine clinical diagnostic imaging, but also in research, including clinical trials. Over the past years, PET technology development brought new innovative PET systems to the commercial market: silicon photomultiplier (SiPM)-based or ‘digital’ PET systems, and large axial field-of-view or ‘total body’ PET systems. This thesis describes the technical performance characteristics of these new PET technologies and, in addition, associated optimization of image quality and activity administration is reported. Furthermore, clinical implications and future perspectives regarding these innovations in the field of nuclear medicine and molecular imaging and other medical disciplines are discussed
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