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991.
André J. Torii Rafael H. Lopez Leandro F. F. Miguel 《Structural and Multidisciplinary Optimization》2016,54(2):317-332
There are available in the literature several papers on the development of methods to decouple the reliability analysis and the structural optimization to solve RBDO problems. Most of them focused on strategies that employ the First Order Reliability Method (FORM) to approximate the reliability constraints. Despite of all these developments, one limitation prevailed: the lack of accuracy in the approximation of the reliability constraints due to the use of FORM. Thus, in this paper, a novel approach for RBDO is presented in order to overcome such a limitation. In this approach, we use the concept of shifting vectors, originally developed in the context of the Sequential Optimization and Reliability Assessment (SORA). However, the shifting vectors are found and updated based on a novel strategy. The resulting framework is able to use any technique for the reliability analysis stage, such as Monte Carlo simulation, second order reliability methods, stochastic polynomials, among others. Thus, the proposed approach overcomes the aforementioned limitation of most of RBDO decoupling techniques, which required the use of FORM for reliability analysis. Several examples are analyzed in order to show the effectiveness of the methodology. Focus is given on examples that are poorly solved or even cannot be tackled by FORM based approaches, such as highly nonlinear limit state functions comprised by a maximum operator or problems with discrete random variables. It should be remarked that the proposed approach was not developed to be more computationally efficient than RBDO decoupling strategies based FORM, but to allow the utilization of any, including more accurate, reliability analysis method. 相似文献
992.
Melo Miguel Barbosa Luís Bessa Maximino Debattista Kurt Chalmers Alan 《Multimedia Tools and Applications》2017,76(15):16605-16623
Multimedia Tools and Applications - HDR video on mobile devices is in its infancy and there are no solutions yet that can achieve full HDR video reproduction due to computational power limitations.... 相似文献
993.
994.
Voltage‐Induced Coercivity Reduction in Nanoporous Alloy Films: A Boost toward Energy‐Efficient Magnetic Actuation 下载免费PDF全文
Alberto Quintana Jin Zhang Eloy Isarain‐Chávez Enric Menéndez Ramón Cuadrado Roberto Robles Maria Dolors Baró Miguel Guerrero Salvador Pané Bradley J. Nelson Carlos Maria Müller Pablo Ordejón Josep Nogués Eva Pellicer Jordi Sort 《Advanced functional materials》2017,27(32)
Magnetic data storage and magnetically actuated devices are conventionally controlled by magnetic fields generated using electric currents. This involves significant power dissipation by Joule heating effect. To optimize energy efficiency, manipulation of magnetic information with lower magnetic fields (i.e., lower electric currents) is desirable. This can be accomplished by reducing the coercivity of the actuated material. Here, a drastic reduction of coercivity is observed at room temperature in thick (≈600 nm), nanoporous, electrodeposited Cu–Ni films by simply subjecting them to the action of an electric field. The effect is due to voltage‐induced changes in the magnetic anisotropy. The large surface‐area‐to‐volume ratio and the ultranarrow pore walls of the system allow the whole film, and not only the topmost surface, to effectively contribute to the observed magnetoelectric effect. This waives the stringent “ultrathin‐film requirement” from previous studies, where small voltage‐driven coercivity variations were reported. This observation expands the already wide range of applications of nanoporous materials (hitherto in areas like energy storage or catalysis) and it opens new paradigms in the fields of spintronics, computation, and magnetic actuation in general. 相似文献
995.
Cristina Martín Koen Kennes Mark Van der Auweraer Johan Hofkens Gustavo de Miguel Eva M. García‐Frutos 《Advanced functional materials》2017,27(41)
This study reports on the use of a self‐assembling organogel, 5‐(4‐nonylphenyl)‐7‐azaindole ( 1 ), as a new emitter in small‐molecule organic light emitting devices (OLEDs). The theoretical calculations along with the photophysical characterization studies suggest the coexistence of the monomer and dimer species at high concentration of compound 1 . The presence of this type of dimer (formed via H‐bonding) is responsible for the increased emission. However, the most notable feature is the 3D network of vastly interconnected fibers formed in the organogel that modifies the photophysical properties. Based on this, several OLED architectures are made in order to understand the mechanism involved in the electroluminescence (EL) behavior of 1 . Although the position of the EL spectra differs from that of the photoluminescence (PL) spectra, the trends observed in the device properties perfectly match with dimer formation. In this framework a better device performance is associated to a higher efficiency of dimer formation, which optimizes in the OLED prepared from the organogel. Therefore, these results show that the rational combination of a moiety showing a strong PL intensity increased upon aggregation with organogel properties is an efficient strategy to create alternative emitters for OLED devices. 相似文献
996.
Diego Ruiz Blanca del Rosal María Acebrón Cristina Palencia Chen Sun Juan Cabanillas‐González Miguel López‐Haro Ana B. Hungría Daniel Jaque Beatriz H. Juarez 《Advanced functional materials》2017,27(6)
Temperature sensing in biological media (cells, tissues, and living organisms) has become essential in the development of the last generation of diagnostics and therapeutic strategies. Thermometry can be used for early detection of different diseases, such as cancer, stroke, or inflammation processes, one of whose incipient symptoms is the appearance of localized temperature singularities. Luminescence nanothermometry, as a tool to accurately provide temperature sensing in biological media, requires the rational design and development of nanothermometers operating in the second biological window. In this work, this is achieved using Ag/Ag2S nanocrystals as multiparametric thermal sensing probes. Temperature sensing with remarkably high sensitivity (4% °C?1) is possible through intensity‐based measurements, as their infrared emission is strongly quenched by small temperature variations within the biological range (15–50 °C). Heating also results in a remarkable redshift of the emission band, which allows for concentration‐independent temperature sensing based on infrared ratiometric measurements, with thermal sensitivity close to 2% °C?1. These results make Ag/Ag2S nanocrystals the most sensitive among all noncomposite nanothermometers operating in the second biological window reported so far, allowing for deep‐tissue temperature measurements with low uncertainty (0.2 °C). 相似文献
997.
Milena Vega Montaña Elviro Ramón Cerro Miguel Ángel Galán 《Chemical Engineering Communications》2017,204(7):750-760
Rigid adsorbents used as matrix skeleton have advantages over soft gel media for downstream processing of proteins. The adsorption of bovine serum albumin (BSA) has been investigated on a rigid ceramic monolith coated with cross-linked microporous agarose (D5). The physical properties of the adsorbent and the adsorption equilibria, adsorption kinetics, and mass transfer behavior have been studied for five different flow rates, with a pH value ranging from pH 4.5 to 7.0. The optimal working flow rate was 14.0?cm3/min, and using this flow rate, increasing the pH does not generate a significant improvement in the adsorption capacity. The rates of BSA adsorption have been measured and it was possible to describe a theoretical model, in which the mass transfer involves a dispersion coefficient (kdisp), which describes the mass transfer in the adsorbent surface, from the volume of the protein solution to the agarose surface. This parameter presents an exponential tendency by increasing the flow rate from 2.37?×?10?6 to 87.40?×?10?6?cm/s for n?=?1. Values obtained for the adsorption kinetic constant (kads) followed the trend of the mass transfer parameter, increasing with the flow rate from 1.94?×?104 to 117.39?×?104?cm2/mol?s. The theoretical model predicts the protein concentration in equilibrium for successive column reuses and it can be readily used to determine the optimal reuse of column. Likewise, for a maximum flow rate of 14?cm3/min, pressure drop was 0.04?MPa, being an advantage in front of packed columns that have higher pressure drop. 相似文献
998.
Onofre A. Morfín Riemann Ruiz-Cruz Fredy A. Valenzuela Miguel A. Murillo Abel E. Quezada 《电力部件与系统》2018,46(3):302-315
One of the most important bases for designing robust closed-loop controllers applied to induction motor with high performance is establishing its mathematical model and state observers, as well as the parameter identification with high accuracy. In this paper, a step-by-step mathematical model of the squirrel-cage induction motor is described at αβ coordinate frame where the parameters are defined in detailed form; the rotor flux linkages and load torque are estimated via an asymptotic observer; the induction motor parameter identification is performed via a data acquisition board, applying dynamic and steady-state tests. Inductances of the induction motor model are calculated using the proposed relationships between the magnetically coupled circuit and equivalent circuit model. The mathematical model, state observers, and parameter identification procedure of squirrel-cage induction motor are validated via comparison of simulation signals with their corresponding real-time signals. This validation is made experimentally by a steady-state test, where load conditions are changed via a dynamometer which is belt coupled with the squirrel-cage induction motor. 相似文献
999.
Performance evaluation of edge-computing platforms for the prediction of low temperatures in agriculture using deep learning 总被引:1,自引:0,他引:1
Guillén Miguel A. Llanes Antonio Imbernón Baldomero Martínez-España Raquel Bueno-Crespo Andrés Cano Juan-Carlos Cecilia José M. 《The Journal of supercomputing》2021,77(1):818-840
The Journal of Supercomputing - The Internet of Things (IoT) is driving the digital revolution. AlSome palliative measures aremost all economic sectors are becoming “Smart” thanks to... 相似文献
1000.
Javier Fontecha Lourdes Amigo Miguel Angel de la Fuente Manuela Juarez Mercedes Ramos Mohamed El-Shikh Safinaz El-Shibiny 《Zeitschrift für Lebensmitteluntersuchung und -Forschung A》1990,191(4-5):310-312
Summary The changes in the proteins and fats of Ras cheese prepared from ultrafiltered milk (UF) were followed during ripening. The soluble protein fraction was made up of whey protein which resisted hydrolysis during ripening. The insoluble protein fraction of fresh cheese was made up mainly of-casein,-casein ands1-I, indicating pronounced proteolysis during the salting step. Further ripening was accompanied with decrease ins1-I and increase in-casein. The free fatty acids (FFA) of UF Ras cheese increased with advanced ripening. The pattern of FFA in Ras cheese was similar to that of bovine milk triacylglycerols.
Veränderungen in der Zusammensetzung von Ras-Käse aus ultrafiltrierter Milch während der Reifung
Zusammenfassung Es wurden die Veränderungen der Proteine und der Fettfraktionen von Ras-Käse aus ultrafiltrierter Milch während der Reifung studiert. Die lösliche Proteinfraktion bestand aus Molkeproteinen, die der Hydrolyse während der Reifung widerstand. Die unlösliche Proteinfraktion des frischen Käses bestand aus-Casein,-Casein unds1-I, was auf starke Proteolyse während des Einsalzens hinweist. In der nachfolgenden Reifung wurde eine Abnahme dess1-Caseins und eine Zunahme der-Caseine beobachtet. Die freien Fettsäuren des Ras-Käses nahmen während der Reifung zu. Das Muster der freien Fettsäuren des Ras-Käses und das der Milchtriglyceride sind ähnlich.相似文献