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91.
This article deals with the development of learning methods for an intelligent control system for an autonomous mobile robot.
On the basis of visual servoing, an approach to learning the skill of tracking colored guidelines is proposed. This approach
utilizes a robust and adaptive image processing method to acquire features of the colored guidelines and convert them into
the controller input. The supervised learning procedure and the neural network controller are discussed. The method of obtaining
the learning data and training the neural network are described. Experimental results are presented at the end of the article.
This work was presented, in part, at the Sixth International Symposium on Artificial Life and Robotics, Tokyo, Japan, January
15–17, 2001 相似文献
92.
Malyarevich AM Denisov IA Savitsky VG Yumashev KV Lipovskii AA 《Applied optics》2000,39(24):4345-4347
By using a PbS-doped phosphate glass as an intracavity saturable absorber, we achieved passive Q switching of a 1.54-mum Er:Yb:glass laser. We obtained Q-switched pulses with 110-ns duration and 0.2-mJ energy. The saturation intensity at 1.54 mum was estimated to be ~60 kW/cm(2). 相似文献
93.
Kudryashova Elena V.; Artemova Tatiana M.; Vinogradov Alexei A.; Gladilin Alexander K.; Mozhaev Vadim V.; Levashov Andrey V. 《Protein engineering, design & selection : PEDS》2003,16(4):303-309
Formation of enzymeoligoamine complexes was suggestedas an approach to obtain biocatalysts with enhanced resistancetowards inactivation in waterorganic media. Complex formationresults in broadening (by 2040% v/v ethanol) of the rangeof cosolvent concentrations where the enzyme retains its catalyticactivity (stabilization effect). At moderate cosolvent concentrations(2040% v/v) complex formation activates the enzyme (by36 times). The magnitude of activation and stabilizationeffects increases with the number of possible electrostaticcontacts between the protein surface and the molecules of oligoamines(OA). Circular dichroism spectra in the far-UV region show thatcomplex formation stabilizes protein conformation and preventsaggregation in waterorganic solvent mixtures. Two populationsof the complexes with different thermodynamic stabilities werefound in -chymotrypsin (CT)OA systems depending on theCT/OA ratio. The average dissociation constants and stoichiometriesof both low- and high-affinity populations of the complexeswere estimated. It appears that it is the low-affinity siteson the CT surface that are responsible for the activation effect. 相似文献
94.
Lik-Kwan Shark Author Vitae Andrey A. Kurekin Author Vitae Author Vitae 《Pattern recognition》2007,40(5):1432-1450
By extending the previously proposed geometric branch-and-bound algorithm with bounded alignment for point pattern matching, the paper presents the development and evaluation of a new and fast algorithm for image registration based on line segments. Using synthetically generated data sets with randomly distributed line segments and hard test cases with highly symmetric line patterns, as well as real remote sensing images, the developed algorithm is shown to be computationally fast, highly robust, capable of handling severely corrupted data sets with considerable line segment position errors as well as significant fragmented and spurious line segments in the images to be matched. 相似文献
95.
Numerical method for modeling the E-polarized wave scattering by electrically large quasioptical two-dimensional (2-D) reflectors is presented. Reflectors are assumed zero-thickness and perfectly electrically conducting. Efficient numerical solution is obtained from the coupled singular integral equations discretized using new quadrature formulas of interpolation type. It has controlled accuracy and deals with small-size matrices. To simulate a small-horn feeding, the incident field is taken as a beam generated by a complex-source-point (CSP) current. Presented numerical results validate empirical rule of -10 dB edge illumination needed to provide the best electromagnetic performance of reflector 相似文献
96.
Andrey Sarikov Jens Schneider Martin Muske Ina Sieber Stefan Gall 《Thin solid films》2007,515(19):7465-7468
The aluminium-induced layer-exchange process allows to grow thin large-grained polycrystalline Si films on foreign substrates. A characteristic feature of these films is the preferential (100) orientation of Si grains, favourable for subsequent epitaxial thickening at low temperatures. In this work, a model based on the preferential nucleation is proposed, which elucidates a possible origin of the preferential (100) orientation and its sensitivity to the preparation and process conditions. The probability of Si nuclei to have respective orientation is attributed to the nucleation barrier, i.e. the critical value of the change of the Gibbs energy during nucleation. The preferential orientation is formed statistically by the nuclei having the lowest nucleation barriers. 相似文献
97.
The 2-D problem of diffraction by a gap between two orthogonal semi-infinite barriers is considered. The method of reflections
is applied and the diffraction problem is reformulated as a propagation problem on a multi-sheet surface. An auxiliary problem,
with a single incident wave, is formulated. By applying an embedding formula the auxiliary problem is reduced to that of finding
a set of edge Green’s functions for the surface. The edge Green’s functions are proven to satisfy two sets of differential
equations: the coordinate equations and the spectral equation. Although too complicated to be solved analytically, these ordinary differential equations offer some advantages over partial
differential equations or integral equations. 相似文献
98.
Reduto I. V. Chervinskii S. D. Kamenskii A. N. Karpov D. V. Lipovskii A. A. 《Technical Physics Letters》2016,42(1):93-95
Technical Physics Letters - Self-organized metal nanostructures have been obtained by an original method on the surface of soda–lime glasses. The nanostructures are grown by heat treatment of... 相似文献
99.
Temperature‐Dependent Exciton and Trap‐Related Photoluminescence of CdTe Quantum Dots Embedded in a NaCl Matrix: Implication in Thermometry 下载免费PDF全文
Sergii Kalytchuk Olga Zhovtiuk Stephen V. Kershaw Radek Zbořil Andrey L. Rogach 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(4):466-476
Temperature‐dependent optical studies of semiconductor quantum dots (QDs) are fundamentally important for a variety of sensing and imaging applications. The steady‐state and time‐resolved photoluminescence properties of CdTe QDs in the size range from 2.3 to 3.1 nm embedded into a protective matrix of NaCl are studied as a function of temperature from 80 to 360 K. The temperature coefficient is found to be strongly dependent on QD size, with the highest sensitivity obtained for the smallest size of QDs. The emission from solid‐state CdTe QD‐based powders is maintained with high color purity over a wide range of temperatures. Photoluminescence lifetime data suggest that temperature dependence of the intrinsic radiative lifetime in CdTe QDs is rather weak, and it is mostly the temperature‐dependent nonradiative decay of CdTe QDs which is responsible for the thermal quenching of photoluminescence intensity. By virtue of the temperature‐dependent photoluminescence behavior, high color purity, photostability, and high photoluminescence quantum yield (26%–37% in the solid state), CdTe QDs embedded in NaCl matrices are useful solid‐state probes for thermal imaging and sensing over a wide range of temperatures within a number of detection schemes and outstanding sensitivity, such as luminescence thermochromic imaging, ratiometric luminescence, and luminescence lifetime thermal sensing. 相似文献
100.
Virus Matryoshka: A Bacteriophage Particle—Guided Molecular Assembly Approach to a Monodisperse Model of the Immature Human Immunodeficiency Virus 下载免费PDF全文
Pooja Saxena Li He Andrey Malyutin Siddhartha A. K. Datta Alan Rein Kevin M. Bond Martin F. Jarrold Alessandro Spilotros Dmitri Svergun Trevor Douglas Bogdan Dragnea 《Small (Weinheim an der Bergstrasse, Germany)》2016,12(42):5862-5872
Immature human immunodeficiency virus type 1 (HIV‐1) is approximately spherical, but is constructed from a hexagonal lattice of the Gag protein. As a hexagonal lattice is necessarily flat, the local symmetry cannot be maintained throughout the structure. This geometrical frustration presumably results in bending stress. In natural particles, the stress is relieved by incorporation of packing defects, but the magnitude of this stress and its significance for the particles is not known. In order to control this stress, we have now assembled the Gag protein on a quasi‐spherical template derived from bacteriophage P22. This template is monodisperse in size and electron‐transparent, enabling the use of cryo‐electron microscopy in structural studies. These templated assemblies are far less polydisperse than any previously described virus‐like particles (and, while constructed according to the same lattice as natural particles, contain almost no packing defects). This system gives us the ability to study the relationship between packing defects, curvature and elastic energy, and thermodynamic stability. As Gag is bound to the P22 template by single‐stranded DNA, treatment of the particles with DNase enabled us to determine the intrinsic radius of curvature of a Gag lattice, unconstrained by DNA or a template. We found that this intrinsic radius is far larger than that of a virion or P22‐templated particle. We conclude that Gag is under elastic strain in a particle; this has important implications for the kinetics of shell growth, the stability of the shell, and the type of defects it will assume as it grows. 相似文献