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51.
Tomáš Brázdil Javier Esparza Stefan Kiefer Antonín Kučera 《Formal Methods in System Design》2013,43(2):124-163
The paper gives a summary of the existing results about algorithmic analysis of probabilistic pushdown automata and their subclasses. 相似文献
52.
In this paper, we analyse a systematically designed and easily tunable backstepping-based boundary control concept for a gantry crane with heavy chain and payload. The corresponding closed-loop system is formulated as an abstract evolution equation in an appropriate Hilbert space. Non-restrictive conditions for the controller coefficients are derived, under which the solutions are described by a C0-semi-group of contractions, and are asymptotically stable. Moreover, by applying Huang's theorem we can finally even show that under these conditions the controller renders the closed-loop system exponentially stable. 相似文献
53.
Valery V. Val’kov Anton O. Zlotnikov 《Journal of Superconductivity and Novel Magnetism》2013,26(9):2885-2886
An interference of heavy-fermion superconductivity (SC) and antiferromagnetism (AFM) has been studied in the framework of the periodic Anderson model with the superexchange interaction between localized electrons. It has been shown that pressure-induced energy change of the localized states leads to modifying antiferromagnetic and superconducting order parameters. Conditions have been found for the coexistence of SC and AFM in the model. Theoretical results of the pressure effects on the ground state character of the heavy-fermion systems are in good agreement with experimental data for a rare-earth intermetallic compound CeRhIn5. The divergence of the effective electron mass produced by suppressing the long-range antiferromagnetic order has also been analyzed in the same framework. 相似文献
54.
Martti Heinonen Miltiadis Anagnostou Stephanie Bell Mark Stevens Robert Benyon Reidun Anita Bergerud Jovan Bojkovski Rien Bosma Jan Nielsen Norbert B?se Plunkett Cromwell Aliye Kartal Dogan Seda Aytekin Ali Uytun Vito Fernicola Krzysztof Flakiewicz Bertrand Blanquart Domen Hudoklin Per Jacobson Anders Kentved Isabel Lóio George Mamontov Alexandra Masarykova Helmut Mitter Regina Mnguni Jan Otych Anton Steiner Nagyné Szilágyi Zsófia Davor Zvizdic 《International Journal of Thermophysics》2012,33(8-9):1422-1437
In the field of humidity quantities, the first CIPM key comparison, CCT-K6 is at its end. The corresponding European regional key comparison, EUROMET.T-K6, was completed in early 2008, about 4?years after the starting initial measurements in the project. In total, 24 NMIs from different countries took part in the comparison. This number includes 22 EURAMET countries, and Russia and South Africa. The comparison covered the dew-point temperature range from ?50?°C to +20?°C. It was carried out in three parallel loops, each with two chilled mirror hygrometers as transfer standards in each loop. The comparison scheme was designed to ensure high quality results with evenly spread workload for the participants. It is shown that the standard uncertainty due to the long-term instability was smaller than 0.008?°C in all loops. The standard uncertainties due to links between the loops were found to be smaller than 0.025?°C at ?50?°C and 0.010?°C elsewhere. Conclusions on the equivalence of the dew-point temperature standards are drawn on the basis of calculated bilateral degrees of equivalence and deviations from the EURAMET comparison reference values (ERV). Taking into account 16 different primary dew-point realizations and 8 secondary realizations, the results demonstrate the equivalence of a large number of laboratories at an uncertainty level that is better than achieved in other multilateral comparisons so far in the humidity field. 相似文献
55.
Dimitar L. Lyutov Kaloyan V. Genkov Anton D. Zyapkov Gichka G. Tsutsumanova Atanas N. Tzonev Lyudmil G. Lyutov Stoyan C. Russev 《Materials Chemistry and Physics》2014
We report a simple one-step synthesis method of large single crystalline Ag (111) hexagonal microplates with sharp edges and a size of up to tens of microns. Single silver crystals were produced by reduction silver nitrate aqueous solution with 4-(methylamino)phenol sulfate. Scanning and transmission electron microscopy, energy-dispersive X-ray spectroscopy, selected area electron diffraction and optical microscopy techniques were combined to characterize the crystals. It is shown that the microplates can be easily dispersed and transferred as single objects onto different substrates and subsequently used as a high quality plasmonic starting material for micromachining of future nanocomponents, using modern top-down techniques like focused-ion beam milling and gas injection deposition. 相似文献
56.
Enhancing Photovoltaic Performance Using an All‐Conjugated Random Copolymer to Tailor Bulk and Interfacial Morphology of the P3HT:ICBA Active Layer 下载免费PDF全文
Anton Li Jojo Amonoo Bingyuan Huang Peter K. Goldberg Anne J. McNeil Peter F. Green 《Advanced functional materials》2014,24(35):5594-5602
Bulk heterojunction (BHJ) solar cells are fabricated using active material blends of poly(3‐hexylthiophene) (P3HT) donor, indene‐C60 bisadduct (ICBA) acceptor, and an all‐conjugated random copolymer (RCP) additive. By optimizing RCP loading, power conversion efficiencies (PCEs) up to 20% higher than those of a binary P3HT:ICBA mixture are achieved. The improved device characteristics are rationalized in terms of the differences between the photoactive thin film morphologies. Energy‐filtered transmission electron microscopy reveals that incorporation of the RCP improves the degree of structural order of the BHJ fibrillar network and increases the extent of microphase separation between P3HT and ICBA. Additionally, a combination of atomic force microscopy and X‐ray photoelectron spectroscopy analysis indicates segregation of the RCP at the free interface, leading to a shift in the surface potentials measured by Kelvin probe force microscopy. These changes, both in the bulk morphology and in the interfacial composition/energetics, are correlated to improved carrier collection efficiency due to a reduction of non‐geminate recombination, which is measured by charge extraction of photogenerated carriers by linearly increasing voltage. 相似文献
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Daniel Ortiz Morales Simon Westerberg Pedro X. La Hera Uwe Mettin Leonid Freidovich Anton S. Shiriaev 《野外机器人技术杂志》2014,31(3):343-363
Working with forestry machines requires a great deal of training to be sufficiently skilled to operate forestry cranes. In view of this, it would be desirable within the forestry industry to introduce automated motions, such as those seen in robotic arms, to shorten the training time and make the work of the operator easier. Motivated by this fact, we have developed two experimental platforms for testing control systems and motion‐planning algorithms in real time. They correspond to a laboratory setup and a commercial version of a hydraulic manipulator used in forwarder machines. The aim of this article is to present the results of this development by providing an overview of our trajectory‐planning algorithm and motion‐control method, with a subsequent view of the experimental results. For motion control, we design feedback controllers that are able to track reference trajectories based on sensor measurements. Likewise, we provide arguments to design controllers in an open‐loop for machines that lack sensing devices. Relying on the tracking efficiency of these controllers, we design time‐efficient reference trajectories of motions that correspond to logging tasks. To demonstrate performance, we provide an overview of extensive testing done on these machines. 相似文献