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101.
Andrzej Banaszuk Vladimir A. Fonoberov Thomas A. Frewen Marin Kobilarov George Mathew Igor Mezic Alessandro Pinto Tuhin Sahai Harshad Sane Alberto Speranzon Amit SuranaAuthor vitae 《Annual Reviews in Control》2011,35(1):77-98
Development of robust dynamical systems and networks such as autonomous aircraft systems capable of accomplishing complex missions faces challenges due to the dynamically evolving uncertainties coming from model uncertainties, necessity to operate in a hostile cluttered urban environment, and the distributed and dynamic nature of the communication and computation resources. Model-based robust design is difficult because of the complexity of the hybrid dynamic models including continuous vehicle dynamics, the discrete models of computations and communications, and the size of the problem. We will overview recent advances in methodology and tools to model, analyze, and design robust autonomous aerospace systems operating in uncertain environment, with stress on efficient uncertainty quantification and robust design using the case studies of the mission including model-based target tracking and search, and trajectory planning in uncertain urban environment. To show that the methodology is generally applicable to uncertain dynamical systems, we will also show examples of application of the new methods to efficient uncertainty quantification of energy usage in buildings, and stability assessment of interconnected power networks. 相似文献
102.
Stephan van Reenen Piotr Matyba Andrzej Dzwilewski René A. J. Janssen Ludvig Edman Martijn Kemerink 《Advanced functional materials》2011,21(10):1795-1802
Incorporation of ions in the active layer of organic semiconductor devices may lead to attractive device properties like enhanced injection and improved carrier transport. In this paper, we investigate the effect of the salt concentration on the operation of light‐emitting electrochemical cells, using experiments and numerical calculations. The current density and light emission are shown to increase linearly with increasing ion concentration over a wide range of concentrations. The increasing current is accompanied by an ion redistribution, leading to a narrowing of the recombination zone. Hence, in absence of detrimental side reactions and doping‐related luminescence quenching, the ion concentration should be as high as possible. 相似文献
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105.
Tomasz Rzychoń Andrzej Kiełbus Jan Cwajna Jarosław Mizera 《Materials Characterization》2009,60(10):1107-1113
The AE44 (Mg–4Al–4RE) alloy was prepared by a hot-chamber die casting method. The microstructure, microstructural stability and creep properties at 175 °C were investigated. The microstructure was analyzed by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and the Rietveld method. The results show that die cast AE44 magnesium alloy consists of α-Mg, Al11RE3, Al2RE and Al2.12RE0.88 phases. The Al11RE3 phase is thermally stable at 175 °C whereas the metastable Al2.12RE0.88 phase undergoes a transition into the equilibrium Al2RE phase. The alloy investigated is characterized by good creep properties at temperatures of 175 °C and 200 °C. 相似文献
106.
Formation of mesoglobules in aqueous media from thermo-sensitive poly(ethoxytriethyleneglycol acrylate) 总被引:1,自引:1,他引:0
Natalia Toncheva-Moncheva Philip Dimitrov Christo B. Tsvetanov Barbara Robak Barbara Trzebicka Andrzej Dworak Stanislav Rangelov 《Polymer Bulletin》2011,67(7):1335-1346
A series of six poly(ethoxytriethyleneglycol acrylate) (PETEGA) homopolymers were synthesized by atom transfer radical polymerization,
reversible addition-fragmentation transfer polymerization, and anionic polymerization in order to cover a molecular weight
range from 7,000 to 40,000 Da. The polymers exhibited a lower critical solution temperature (LCST) behavior in water, which
was observed by the occurrence of a cloud point (CP) at around 35 °C. The transmittance of visible light versus temperature
dependence overlapped during the cooling and the heating cycles, showing almost a complete lack of hysteresis. Moreover, instead
of the occurrence of an uncontrolled macroscopic phase separation, stable colloidal aggregates (mesoglobules) of narrow distribution
in particle size were formed in water at temperatures above the LCST of PETEGA at 1 g L−1 solutions. The dimensions of the mesoglobules ranged from 91 to 235 nm, and particle size was not influenced by the molecular
weight of PETEGA. Temperature changes caused considerable variations of the mesoglobules dimensions, which were smaller at
higher temperatures. The addition of an anionic surfactant simultaneously increased the CP values by 4–6 °C and lowered the
dimensions of the mesoglobules. 相似文献
107.
Frydrychowski AF Gumiński W Rojewski M Kaczmarek J Juzwa W 《IEEE transactions on bio-medical engineering》2002,49(8):887-904
This paper presents technical foundations for a new technique of near-infrared transillumination-backscattering sounding, which is designed to enable noninvasive detection and monitoring of changes in the width of the subarachnoid space (SAS) and magnitude of cerebrovascular pulsation in humans. The key novelty of the technique is elimination of influence of blood flow in the scalp on the signals received from two infrared sensors-proximal and distal. A dedicated digital algorithm is used to estimate on line the ratio of the powers of received signals, referred to as two-sensor distal-to-proximal received power quotient, TQ (t). The propagation duct for NIR radiation reaching the distal sensor is the SAS filled with translucent cerebrospinal fluid. Information on slow fluctuations of the average width of the SAS is contained in the slow-variable part of the TQ (t), called the subcardiac component, and in TQ itself. Variations in frequency and magnitude of faster oscillations of the width of that space around the baseline value, dependent on cerebrovascular pulsation, are reflected in instantaneous frequency and envelope of the fast-variable component. Frequency and magnitude of the cerebrovascular pulsation depend on the action of the heart, so this fast-variable component is referred to as the cardiac component. 相似文献
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109.
Andrzej Buller Michal Joachimczak Juan Liu Katsunori Shimohara 《Artificial Life and Robotics》2005,9(4):197-201
This article presents the key assumptions and current status of the ATR Artificial Brain Project being undertaken to create
Volitron, a device equipped with circuitry that enables the emergence of thought. Such thought would be recognized from Volitron's
specific communication behaviors. The project consists of three complementary themes: psychodynamic architecture, brain-specific
evolvable hardware, and the management of brain-building. The psychodynamic architecture is designed to develop automatically,
driven by “pleasure” coming from discharges of tension gathered in special tension-accumulating devices. Tension-discharging
patterns come first of all from the robot's interactions with its care giver/provider. For the dedicated hardware, we developed
qcellular-automata (qCA), in which groups of uniform logic primitives (q-cells) serve as spike-train-processing units, as well as pulsed para-neural networks (PPNN) that can be evolved, using fuzzified
signals and a genetic algorithm combined with hill climbing, and converted into qCA. The psychodynamic ideas were tested using three robots: Neko, equipped with a pleasure-driven associator, Miao, equipped with MemeStorms (a special working memory in which conflicting ideas fight for access to the long-term memory and
actuators), and Miao+, whose brain is equipped with a growing neural network.
This work was presented in part at the 9th International Symposium on Artificial Life and Robotics, Oita, Japan, January 28–30,
2004 相似文献
110.
Pitch detection methods are widely used for extracting musical data from digital signals. A review of those methods is presented in the paper. Since musical signals may contain noise and distortion, detection results can be erroneous. In this paper a new method employing music prediction to support pitch determination is introduced. This method was developed in order to override disadvantages of standard pitch detection algorithms. The new approach utilizes signal segmentation and pitch prediction based on musical knowledge extraction employing artificial neural networks. Signal segmentation allows for estimating the pitch for a single note as a whole, therefore suppressing errors in transient and decay phases. Pitch prediction helps correcting pitch estimation errors by tracking musical context of the analyzed signal. As it was shown in the experimental results, pitch estimation errors may be reduced by using both signal segmentation and music prediction techniques. 相似文献