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Schubert R. Carvalho Ronan Boulic Creto A. Vidal Daniel Thalmann 《The Visual computer》2013,29(3):171-188
We explore an approach to full-body motion editing with linear motion models, prioritized constraint-based optimization and latent-space interpolation. By exploiting the mathematical connections between linear motion models and prioritized inverse kinematics (PIK), we formulate and solve the motion editing problem as an optimization function whose differential structure is rich enough to efficiently optimize user-specified constraints within the latent motion space. Performing motion editing within latent motion spaces has the advantage of handling pose transitions and consequently motion flow by construction from single key-frame editing. To handle motion adjustments from multiple key-frame and trajectory constraints, we developed a latent-space interpolation technique by exploiting spline functions. Such an approach handles per-frame adjustments generating smooth animations, while avoiding the computational expense of joint space interpolations. We demonstrate the usefulness of this approach by editing and generating full-body reaching and walking jump animations in challenging environment scenarios. 相似文献
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C. Gomez-reino M. V. Perez C. Bao M. T. Flores-arias S. Vidal 《Journal of Modern Optics》2013,60(1):91-102
Abstract A study of diffraction-free and diffraction-limited propagation of light with transverse amplitude in sech through a planar waveguide with hyperbolic secant refractive index profile is presented. Analytical solutions by the stationary phase method are obtained. A particular case is analysed. 相似文献
46.
Romário Mauricio Urbanetto Nogueira Carlos Enrique Niño Bohórquez Igor Giacomelli Zanella 《Welding International》2017,31(3):161-172
Despite their similarity, the MIG/MAG and Tubular Electrode processes display particular features with regard to arc stability and variability in the characteristics of the beads. Thus, selection of one of these processes for a specific application will have to consider how these particular features affect the quality of the welds. To support this choice, the present study aimed to investigate how changing the average current affects the stability and regularity of metal transfer in welds carried out with constant voltage and pulsed current and compare the variability in the geometry and dilution of these welds. To achieve these aims, automatic welding was carried out, with steel ABNT 1020 as base metal and wire AWS ER70S-6 and AWS E71T-1 as filler metals. Besides the welds with variation in the average current, the tests involved determination of the parameters for occurrence of stable short circuiting, drop and pulsed transfer. The results showed that the voltage that gives the highest stability in short circuiting transfer is independent of the welding speed and increases with the wire speed, and also showed that welds made with hollow wire displayed greater variability compared to solid wire. 相似文献
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Dongming Liu Yuhong Xiong Ying Li Troy D. Topping Yizhang Zhou Chris Haines Joseph Paras Darold Martin Deepak Kapoor Julie M. Schoenung Enrique J. Lavernia 《Metallurgical and Materials Transactions A》2013,44(4):1908-1916
The influence of tooling material, i.e., graphite and WC-Co, on the microstructure of a spark plasma sintering (SPS) consolidated, nanostructured aluminum alloy is studied in this paper. The results show that tooling selection influences microstructure evolution, independent of process parameters. The influence of tooling on microstructure is rationalized on the basis of the following factors: heating rate, electrical current density, localized heating, and imposed pressure. A theoretic framework, based on the physical properties of graphite and WC-Co, is formulated to explain the observed behavior. 相似文献
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In this article we present Ethane, a parallel heterogeneous metaheuristic model specifically designed for its execution on heterogeneous hardware environments. With Ethane we propose a hybrid parallel search algorithm inspired in the structure of the chemical compound of the same name, implementing a heterogeneous island model based in the structure of the chemical bonds of the ethane compound. Here we also shape a schema for describing a complete family of parallel heterogeneous metaheuristics inspired by the structure of hydrocarbons in nature, HydroCM (HydroCarbon inspired Metaheuristics), establishing a resemblance between atoms and computers, and between chemical bonds and communication links. Our goal is to gracefully match computers of different computing power to algorithms of different behavior (genetic algorithm and simulated annealing in this study), all them collaborating to solve the same problem. In addition to the nice natural metaphor we will show that Ethane, though simple, can solve search problems in a faster and more robust way than well-known panmictic and distributed algorithms very popular in the literature, as well as can achieve a better exploration/exploitation balance during the search process. 相似文献
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Mohammad Hamdan Alkhraisat Jatsue Cabrejos-Azama Carmen Rueda Rodríguez Luis Blanco Jerez Enrique López Cabarcos 《Materials science & engineering. C, Materials for biological applications》2013,33(1):475-481
The use of magnesium-doped ceramics has been described to modify brushite cements and improve their biological behavior. However, few studies have analyzed the efficiency of this approach to induce magnesium substitution in brushite crystals. Mg-doped ceramics composed of Mg-substituted β-TCP, stanfieldite and/or farringtonite were reacted with primary monocalcium phosphate (MCP) in the presence of water. The cement setting reaction has resulted in the formation of brushite and newberyite within the cement matrix. Interestingly, the combination of SAED and EDX analyses of single crystal has indicated the occurrence of magnesium substitution within brushite crystals. Moreover, the effect of magnesium ions on the structure, and mechanical and setting properties of the new cements was characterized as well as the release of Ca2 + and Mg2 + ions. Further research would enhance the efficiency of the system to incorporate larger amounts of magnesium ions within brushite crystals. 相似文献
50.
Hajer Ben-Romdhane Enrique Alba Saoussen Krichen 《Soft Computing - A Fusion of Foundations, Methodologies and Applications》2013,17(6):1005-1017
Dynamic optimization problems (DOPs) have attracted considerable attention due to the wide range of problems they can be applied to. Lots of efforts have been expended in modeling dynamic situations, proposing algorithms, and analyzing the results (too often in a visual way). Numeric performance measurements and their statistical validation have been however barely used in the literature. Most of works in DOPs report only the best-of-generation fitness, due to its simplicity of computation. Although this measure indicates the best algorithm in terms of fitness, it does not provide any details about the actual strength and weakness of each algorithm. In this article, we conduct a comparative study among algorithms of different search modes via several performance measures to demonstrate their relative advantages. We discuss the role of using different performance measures in drawing balanced conclusions about algorithms for DOPs. 相似文献