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81.
82.
Raşit Köker 《Engineering with Computers》2013,29(4):507-515
The neural-network-based inverse kinematics solution is one of the recent topics in the robotics because of the fact that many traditional inverse kinematics problem solutions such as geometric, iterative and algebraic are inadequate for redundant robots. However, since the neural networks work with an acceptable error, the error at the end of inverse kinematics learning should be minimized. In this study, simulated annealing (SA) algorithm was used together with the neural-network-based inverse kinematics problem solution robots to minimize the error at the end effector. The solution method is applied to Stanford and Puma 560 six-joint robot models to show the efficiency. The proposed algorithm combines the characteristics of neural network and an optimization technique to obtain the best solution for the critical robotic applications. Three Elman neural networks were trained using separate training sets and different parameters, since one of them can give better results than the others can. The best result is selected within three neural network results by computing the end effector error via direct kinematics equation of the robotic manipulator. The decimal part of the neural network result was improved up to 10 digits using simulated annealing algorithm. The obtained best solution is given to the simulated annealing algorithm to find the best-fitting 10 digits for the decimal part of the solution. The end effector error was reduced significantly. 相似文献
83.
This work theoretically reinvestigates the coarsening of particles controlled by diffusion through a dislocation network, when the dislocation spacing of the network is larger than the maximum particle size and the volume fraction of the particles vanishes. Both a three-dimensional network and a plane one, such as that which might be encountered at a low-angle grain boundary, are treated. It is considered here that the number of dislocation pipes for diffusion increases with distance away from the particle. Under certain reasonable assumptions, at
1/4 steady-state coarsening kinetics is found. The origin of the differences between the present kinetic results (t1/4) and those predictions previously reported in the specialized literature (t
1/5), for similar dislocation geometries, are discussed. The effect of the dislocation annihilation phenomenon on the growth kinetics is also examined qualitatively. 相似文献
84.
Raúl E. Cian Micaela Albarracín Antonela G. Garzón Silvina R. Drago 《International Journal of Food Science & Technology》2022,57(8):4832-4839
Sorghum flour was heat treated for producing an instant dispersion ingredient. The precooked sorghum flour was added with ACE-I and DPP-IV inhibitory sorghum peptides (3.0 g peptide 100 g−1). The product was reconstituted in water, and peptide bioaccessibility was evaluated by equilibrium dialysis method after simulated gastrointestinal digestion. Total peptide dialysability of precooked sorghum flour added with sorghum peptides was higher than those obtained for precooked sorghum flour (315.9 ± 14.8 vs. 45.2 ± 5.6 µmol, respectively) (P < 0.05). The ACE-I and DPP-IV-IC50 values of the bioaccessible peptides from the bioactive product were lower than those obtained for precooked sorghum flour ingredient (1.04 ± 0.12 vs. 1.82 ± 0.09 and 0.86 ± 0.02 vs. 2.12 ± 0.08 mg protein mL−1, for ACE-I and DPP-IV, respectively) indicating a higher activity. Precooked sorghum flour was a good vehicle since it did not affect the bioaccessibility of ACE-I and DPP-IV inhibitory peptides provided by sorghum protein hydrolysate. 相似文献
85.
Kang Bo García García Darío Lijffijt Jefrey Santos-Rodríguez Raúl De Bie Tijl 《Machine Learning》2021,110(10):2905-2940
Machine Learning - Dimensionality reduction and manifold learning methods such as t-distributed stochastic neighbor embedding (t-SNE) are frequently used to map high-dimensional data into a... 相似文献
86.
Muñoz Jairo Alberto Bolmaro Raúl E. Jorge Alberto Moreira Zhilyaev Alexander Cabrera José María 《Metallurgical and Materials Transactions A》2020,51(9):4674-4684
Metallurgical and Materials Transactions A - It is well known that a balance between the generation of low-angle and high-angle grain boundaries (LABG and HAGB) is achieved in materials undergoing... 相似文献
87.
Raúl Tauro Montserrat Serrano-Medrano Omar Masera 《Clean Technologies and Environmental Policy》2018,20(7):1527-1539
Bioenergy is the largest renewable energy source in Mexico with an estimated 4–9% of total current energy demand. There are large uncertainties and contrasting estimates regarding its current extent and end-uses, particularly with traditional uses. However, a large potential exists to improve the efficiency of existing uses and, at the same time, to diversify the use of SBF in the industrial and power sectors. This paper aims at: providing the first updated and comprehensive estimate of current SBF demand in Mexico including traditional and modern uses; providing a consistent estimate of actual SBF supply potential; estimating the total potential substitution of fossil fuels that could be achieved by SBF considering an integrated “modernization scenario”; and finally describing the main barriers limiting SBF to fully triggering its potential. Results show that current SBF consumption reached 481 PJ/yr in 2015; SBF supply potential reaches 3622 PJ/yr, out of which 883 PJ/yr could be used to substitute up to 29% of current demand of FF, mitigating 66 MtCO2e/yr of greenhouse gas (GHG) emissions, or near 88 MtCO2e/yr if mitigation from traditional uses is added. 相似文献
88.
Andrew Turner Raúl Pampin Dieter Leichtle Michael J. Loughlin 《Fusion Engineering and Design》2011,86(9-11):1825-1829
There is increasing demand for fast and accurate neutronics analysis to be conducted on specific ITER components. The ATLAS (accelerated torus-like angular source) algorithm has been developed to accelerate such neutronics calculations by approximating the 3-D plasma volume source as a surface source at the first-wall region of interest. The ATLAS routine rapidly calculates the angular distribution of the unscattered neutron flux at the chosen first wall location, on a discrete angular grid, and writes a surface source for both MCNP and Attila. This discretised source can then be used to accurately reproduce the full 3-D toroidal volume source in angle and energy, and to quickly simulate the irradiation of individual components or regions in the ITER model. While designed for ITER, the method is general in implementation and can be applied to any tokamak. 相似文献
89.
Zoran Ognjanovi? Zoran Markovi? Miodrag Ra?kovi? Dragan Doder Aleksandar Perovi? 《Annals of Mathematics and Artificial Intelligence》2012,65(2-3):217-243
The aim of the paper is to present a sound, strongly complete and decidable probabilistic temporal logic that can model reasoning about evidence. The formal system developed here is actually a solution of a problem proposed by Halpern and Pucella (J Artif Intell Res 26:1–34, 2006). 相似文献
90.
Ha-Kyun Mok Jung-Woong Ra 《Electronics letters》1999,35(2):129-130
An MMIC VCO with a new type of frequency tunable multilayer ceramic resonator for mobile communication is designed and fabricated for the 2 GHz band. The VCO presents a dramatic size reduction and a C/N performance of -100 dBc/Hz at 100 kHz. Its RF output power is about -3 dBm, the frequency tuning range is 110 MHz, and current consumption is 7mA of DC 相似文献