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31.
An instructional approach is presented to improve human performance in solving Bayesian inference problems. Starting from the original text of the classic Mammography Problem, the textual expression is modified and visualizations are added according to Mayer’s principles of instruction. These principles concern coherence, personalization, signaling, segmenting, multimedia, spatial contiguity, and pretraining. Principles of self-explanation and interactivity are also applied. Four experiments on the Mammography Problem showed that these principles help participants answer the questions at significantly improved rates. Nonetheless, in novel interactivity conditions, performance was lowered suggesting that more interaction can add more difficulty for participants. Overall, a leap forward in accuracy was found, with more than twice the participant accuracy of previous work. This indicates that an instructional approach to improving human performance in Bayesian inference is a promising direction. 相似文献
32.
Abolghasem Nourmohammadi Saeid Jalali Asadabadi Mohammad Hasan Yousefi Majid Ghasemzadeh 《Nanoscale research letters》2012,7(1):689
The photoluminescence emission of nanoporous anodic aluminum oxide films formed in phosphoric acid is studied in order to explore their defect-based subband electronic structure. Different excitation wavelengths are used to identify most of the details of the subband states. The films are produced under different anodizing conditions to optimize their emission in the visible range. Scanning electron microscopy investigations confirm pore formation in the produced layers. Gaussian analysis of the emission data indicates that subband states change with anodizing parameters, and various point defects can be formed both in the bulk and on the surface of these nanoporous layers during anodizing. 相似文献
33.
Automating the sizing of transistors in CMOS gates for low‐power and high‐noise margin operation
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Azam Beg 《International Journal of Circuit Theory and Applications》2015,43(11):1637-1654
This paper presents an automatic method for sizing the transistors in CMOS gates. The method utilizes a feedback control system to efficiently optimize the transistor sizes in small and large fan‐in gates, with the primary goal of enhancing noise robustness (as characterized by the static noise margin). The gates retain their robustness under threshold‐voltage variations over a range of supply voltages. The optimized gates not only expend reduced power and energy, but also take up less area than the conventional ones. These multi‐faceted gains, however, do incur some performance loss. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Kamyar Karbasi Arani Mohammad S. Marefat Abolfazl Amrollahi‐Biucky Mohammad Khanmohammadi 《The Structural Design of Tall and Special Buildings》2013,22(3):267-290
Concrete buildings reinforced by plain (smooth) bars are one of the special types of old reinforced concrete buildings that were generally built before the 1970s. As columns are generally the most important structural members of a framed structure, understanding their realistic seismic behavior is very helpful in estimating structural deformations, forces and energy dissipation capacities. Furthermore, in most of old‐framed building structures, columns play a key role in the final behavior because of strong beam–weak column conditions. This article reports the results of experimental monotonic and cyclic tests on four concrete column specimens reinforced by plain bars and with various types of splices. Through the experimental results, it tried to obtain more clarification on the complicated behavior of such old reinforced members as well as the differences compared with relevant results of columns reinforced by deformed bars. It was realized that slip (fixed‐end rotation) contribution is the major source of deformation in all specimens independent from type of splices. Moreover, general mode of behavior was restrained‐rocking action independent of type of splice detailing. A simple theory for the explanation of hysteresis force–displacement response was proposed. The theory assumes a concrete block rocking element that is restrained with plain bars at both ends. Copyright © 2010 John Wiley & Sons, Ltd. 相似文献
36.
Masume Masudi Rahimi Azam Astaneh Reza Poorghasemi 《Protection of Metals and Physical Chemistry of Surfaces》2019,55(2):363-370
Protection of Metals and Physical Chemistry of Surfaces - Corrosion protective coatings were developed on 1050 aluminum alloy through the sol–gel process using... 相似文献
37.
Sadaqat Ali Bilal Anjum Ahmed Hafiz Muzammil Irshad Akolade Idris Bakare Abbas Saeed Hakeem Muhammad Qamaruddin Muhammad Ali Ehsan Sameer Ali Muhammad Umar Azam 《International Journal of Applied Ceramic Technology》2020,17(4):1948-1958
The thermomechanical behavior of micro/nano-alumina (Al2O3) ceramics reinforced with 1-5 wt.% of acid-treated oil fly ash (OFA) was investigated. Composites were sintered using spark plasma sintering (SPS) technique at a temperature of 1400°C by applying a constant uniaxial pressure of 50 MPa. It was evaluated that the fracture toughness of micro- and nanosized composites improved in contrast with the monolithic alumina. Highest fracture toughness value of 4.85 MPam1/2 was measured for the nanosized composite reinforced with 5 wt.% OFA. The thermal conductivity of the composites (nano-/microsized) decreased with the increase in temperature. However, the addition of OFA (1-5 wt.%) in nanosized alumina enhanced the thermal conductivity at an evaluated temperature. Furthermore, a minimum thermal expansion value of 6.17 ppm*K−1 was measured for nanosized Al2O3/5 wt.% OFA composite. Microstructural characterization of Al2O3-OFA composites was done by x-ray diffraction and Raman spectroscopy. Oil fly ash particles were seen to be well dispersed within the alumina matrix. Moreover, the comparative analysis of the nano-/microsized Al2O3/OFA composites shows that the mechanical and thermal properties were improved in nanosized alumina composites. 相似文献
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Investigation of miscibility and phase structure of a novel blend of poly(lactic acid) (PLA)/acrylic rubber (ACM) and its nanocomposite with nanosilica
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In this work, a novel polymer blend containing poly(lactic acid) (PLA) as a biocompatible and biodegradable thermoplastic and acrylic rubber (ACM) is prepared and the miscibility and phase structure of the blend and its nanocomposite (PLA/ACM/nanosilica) are investigated through theoretical and experimental methods. To predict the phase diagram of the blend, a compressible regular solution model was employed, in which an upper critical solution temperature was observed. The model predicted that PLA/ACM blends are immiscible over the whole composition range at temperatures below 260 °C. Performing scanning force microscopy on the blend showed phase separated structures for the blends containing different amounts of the PLA and ACM. This was in accordance with the results of dynamic mechanical analysis, which revealed two distinct glass transition temperatures for the studied blends. The effect of nanometer sized silica particle on morphology and rheological properties of these blends was also investigated. Scanning force microscopy results showed much reduction of droplet size in the blends containing 2 wt % nanosilica. This was attributed to the suppression effect of nanosilica on the droplets coalescences. Rheological measurements confirmed the interaction of both components with the silica nanofiller. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017 , 134, 45499. 相似文献