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71.
Andrés García Higuera Javier de las Morenas 《Journal of Intelligent Manufacturing》2014,25(5):1197-1206
Traditional management and control models can benefit from added levels of intelligence to increase their capability to adapt to the continuous changes in global markets. After reviewing the classical definition of intelligence and its levels, this paper provides a new approach to help increase the responsiveness of management and control to changes and disturbances in the manufacturing supply chain. The ancient concept of the “Tertium Quid” has inspired a three-level community of agents (MAS-TRIO) that is proposed to improve the coordination of all actors involved. The proposed model combines Multi-Agent Systems (MAS) with Radio-Frequency Identification (RFID) to make possible a certain level of Autonomous Intelligence in the decision-taking process. This paper analyses how these levels of intelligence can be applied to management and control, and the performance of the proposed model has been tested at low and mid-levels on an experimental platform representing the facilities of a distribution centre controlled by a network of programmable logic controllers (PLCs). 相似文献
72.
The high computation requirements of global optimization algorithms, when used to solve real optimization problems, have caused the appearance of different parallelization strategies using several parallel computing architectures. In this work, the Universal Evolutionary Global Optimizer is implemented in CUDA to be run on GPU architectures (GPuEGO). This parallelization of the referred evolutionary multimodal optimization algorithm is rather different from other previous parallel implementations designed to be executed into shared or distributed memory processors. In this case, due to the special characteristics of a GPU architecture, the original data structures are not valid and it has been necessary to redefine them and all the functions that operate with them. When this approach is applied the acceleration factors achieved by GPuEGO range from \({\times }\) 6.33 to \({\times }\) 23.20 depending on the test function. 相似文献
73.
Ginés D. Guerrero José M. Cecilia Antonio Llanes José M. García Martyn Amos Manuel Ujaldón 《The Journal of supercomputing》2014,69(1):318-329
The rapidly growing field of nature-inspired computing concerns the development and application of algorithms and methods based on biological or physical principles. This approach is particularly compelling for practitioners in high-performance computing, as natural algorithms are often inherently parallel in nature (for example, they may be based on a “swarm”-like model that uses a population of agents to optimize a function). Coupled with rising interest in nature-based algorithms is the growth in heterogenous computing; systems that use more than one kind of processor. We are therefore interested in the performance characteristics of nature-inspired algorithms on a number of different platforms. To this end, we present a new OpenCL-based implementation of the Ant Colony Optimization algorithm, and use it as the basis of extensive experimental tests. We benchmark the algorithm against existing implementations, on a wide variety of hardware platforms, and offer extensive analysis. This work provides rigorous foundations for future investigations of Ant Colony Optimization on high-performance platforms. 相似文献
74.
M.?MelgosaEmail author R.?Huertas E.?Hita J.?M.?Roa F.?J.?Heredia J.?Alba M.?J.?Moyano 《Journal of the American Oil Chemists' Society》2004,81(4):323-330
A new color scale was developed from a broad data set of 1700 virgin olive oil samples over four crop seasons, which can be
considered highly representative of the whole color range of virgin olive oils available in Spain. This color scale provides
a new set of 60 color standards, improving the results achieved by the old 60-color standards proposed by the bromthymol blue
method. Seeking the greatest possibility of including a near match between colors of virgin olive oils and proposed standards,
we developed our new color scale using a recent uniform color space, with standards placed in a regular rhombohedral lattice
like the one employed by the Uniform Color Scales of the Optical Society of America. The average color difference between
each of the 1700 virgin olive oils and its nearest standard is reduced from 8.17 CIELAB units, using the bromthymol blue standards,
to 3.99 CIELAB units using the new standards. Within a color tolerance of 7.0 CIELAB units, 93.2% of our virgin olive oils
can be classified with the new standards, but only 59.1% with the bromthymol blue ones. In the interest of future adoption,
the performance of the new color standards should be tested by industry and researchers. 相似文献
75.
Aranzazu García M Victoria Ruiz-Méndez Concepción Romero Manuel Brenes 《Journal of the American Oil Chemists' Society》2006,83(2):159-164
By definition, virgin olive oil is consumed unrefined, although a great proportion of the olive oil produced has to be refined
to render it edible. Phenolic compounds are among the substances eliminated during the refining process; in the present work
these were characterized by HPLC, and their evolution during the different refining steps was studied. The complete refining
process removed most polyphenols from oils, but the behavior of individual compounds at each step also was observed. o-Diphenols
(hydroxytyrosol, catechol, and hydroxytyrosol acetate) and flavonoids (luteolin and apigenin) were eliminated first during
the alkaline treatment. Tyrosol and 4-ethylphenol remained in the oil until the deodorization step. A large amount of phenolic
compounds was discovered in the refining by-products such as soapstocks and deodorization distillates. In the latter streams,
the concentrations of tyrosol and 4-ethylphenol reached up to 149 and 3720 mg/kg by-product, respectively. This high level
of 4-ethylphenol and its well-known strong off-odor can interfere during further processing of the deodorization distillates,
and this must be taken into account when deciding what is to become of them. Similarly, the results of this work open the
possibility of recovering phenolic compounds from the “second centrifugation olive oils” by adding a new washing step prior
to the refining process. By including this new step, the most polar polyphenols, hydroxytyrosol and tyrosol, will diffuse
from oil to water and a concentration of up to 1400 mg/L of hydroxytyrosol may be achieved. 相似文献
76.
J. Linares-Pérez R. Caballero-Águila I. García-Garrido 《International journal of systems science》2014,45(7):1548-1562
This paper addresses the optimal least-squares linear estimation problem for a class of discrete-time stochastic systems with random parameter matrices and correlated additive noises. The system presents the following main features: (1) one-step correlated and cross-correlated random parameter matrices in the observation equation are assumed; (2) the process and measurement noises are one-step autocorrelated and two-step cross-correlated. Using an innovation approach and these correlation assumptions, a recursive algorithm with a simple computational procedure is derived for the optimal linear filter. As a significant application of the proposed results, the optimal recursive filtering problem in multi-sensor systems with missing measurements and random delays can be addressed. Numerical simulation examples are used to demonstrate the feasibility of the proposed filtering algorithm, which is also compared with other filters that have been proposed. 相似文献
77.
M. Perez-Luna J.A. Toledo-Antonio F. Hernandez-Beltrán H. Armendariz A. García Borquez 《Catalysis Letters》2002,83(3-4):201-207
The effect of alumina and nickel in sulfated ZrO2 as a catalyst for n-butane isomerization was investigated. Samples were synthesized by supporting nickel sulfated zirconia on boehmite and then calcining the material. The crystalline structure of ZrO2 was studied by X-ray powder diffraction and refined by the Rietveld method. Surface areas were determined by N2 adsorption and BET analysis, while the acid properties were studied by NH3 adsorption. The chemical reaction was carried out in a fixed-bed microreactor at 338 K under atmospheric (78 kPa) or 245 kPa total pressure. Results showed that either nickel or alumina improved the catalytic activity, but a synergic effect was observed when both components assisted. The catalytic activity was related to the relative content of tetragonal zirconia and acid site density. Alumina stabilized tetragonal zirconia increased the acid site density and presumably led to a better dispersion of nickel oxide. The catalytic activity could be related to both oxidation and acid sites produced by nickel. A bimolecular reaction mechanism helps explain the observed trends. The increase in the reaction rate would be explained by the increase in the rate of the initial step of dehydrogenation either caused by a better dispersion of nickel or higher operating pressure. 相似文献
78.
Maritza F. Díaz Gómez Goitybell Martínez Téllez Maikel Arteaga Cruz Rafael Garcés Mancheno 《Journal of the American Oil Chemists' Society》2006,83(11):943-946
Ozonized theobroma fat is used as raw material in the manufacture of pessaries and cosmetic creams. Ozonization of theobroma
fat with water was carried out at different applied ozone dosages, and the resultant PV, acid value, iodine value, total hydroperoxide
content, and FA content were determined. PV and total hydroperoxide content showed a notable increase with applied ozone dosage
up to 35.7 mg/g. Acid value varied slightly from 4.1 to 9.9 mg KOH/g, and the iodine value fell to zero. PV and total hydroperoxide
content increased slightly with a higher applied ozone dosage. The comparison of total hydroperoxide measurement using ferrous
oxidation in xylenol orange assay and traditional iodometric assay for PV determination showed a significant linear correlation.
Small amounts of oleic acid were found in ozonized theobroma fat samples with iodine value equaling zero, which demonstrated
that iodine value determination is an inexact assay. During ozonization of theobroma fat, an increase in acid value of 18.9-fold
with respect to the initial value was observed owing to decomposition of peroxide. 相似文献
79.
Thomas Uchida Alfonso Callejo Javier García de Jalón John McPhee 《Multibody System Dynamics》2014,31(3):371-392
Efficient dynamic simulation code is essential in many situations (including hardware-in-the-loop and model-predictive control applications), and highly beneficial in others (such as design optimization, sensitivity analysis, parameter identification, and controller tuning tasks). When the number of modeling coordinates n exceeds the degrees-of-freedom of the system f, as is often the case when closed kinematic chains are present, the governing dynamic equations consist of n second-order ordinary differential equations (ODEs) coupled with m=n?f algebraic constraint equations. This set of n+m index-3 differential-algebraic equations can be difficult to solve in an efficient yet accurate manner. Embedding (or generalized coordinate partitioning) can be used to obtain f ODEs (one for each independent acceleration), which are generally more amenable to numerical integration; however, the dependent positions are typically computed from the independent positions at each time step. Newton–Raphson iteration is often used for solving the position-level kinematics, but only provides solutions to within a specified tolerance, and can require several iterations to converge. In this work, Gröbner bases are used to obtain recursively solvable symbolic solutions for the dependent positions, which can then be evaluated to within machine precision using a fixed number of arithmetic operations. Natural coordinates are particularly attractive in this context, since the resulting constraint equations are maximally quadratic polynomials and are, therefore, easily triangularized. The proposed approach is suitable for use in an automated formulation procedure and, as demonstrated by three examples, is capable of generating highly efficient simulation code with minimal additional effort required at the formulation stage. 相似文献
80.
Gabino A. Carriedo Francisco J. García Alonso Alejandro Presa Soto 《Journal of Inorganic and Organometallic Polymers and Materials》2007,17(2):399-406
The chiral phosphazene copolymers {[NP(O2C12H8)]0.9[NP(O2C20H12)]0.1} (1) and {[NP(O2C12H8)]0.9[NP(O2C20H10Br2)]0.1}
n
(2) [(O2C12H8) = 2,2′-dioxy-1,1′-biphenyl; (O2C20H12) = R-2,2′-dioxy-1,1′-binaphthyl and (O2C20H10Br2) = R-6,6′-dibromo-2,2′-dioxy-1,1′-binaphthyl] were prepared by sequential substitution from [NPCl2]
n
and the corresponding dihydroxy-biphenyl or binaphthyl reagents in the presence of Cs2CO3 and K2CO3. The reaction of (2) with tBuLi in THF, followed by addition of PPh2Cl and a treatment with SiHCl3/PPh3 to eliminate any oxidized OC6H4P(O)Ph2 groups, gave the phosphine containing copolymer {[NP(O2C12H8)]0.9[NP(O2C20H10[PPh2]2)]0.1}
n
(3), that was used as a chiral ligand to support [Ru(p-cymene)Cl] complexes. The resulting catalyst was active for hydrogen
transfer from isopropyl alcohol to acetophenone but the placement of the Ru centers in the 6,6′-positions of the binaphthoxyphosphazene
units induced no enantioselectivity.
Dedicated to Professor Christopher Allen. 相似文献