4 research outputs found
An improved advertising CTR prediction approach based on the fuzzy deep neural network
<div><p>Combining a deep neural network with fuzzy theory, this paper proposes an advertising click-through rate (CTR) prediction approach based on a fuzzy deep neural network (FDNN). In this approach, fuzzy Gaussian-Bernoulli restricted Boltzmann machine (FGBRBM) is first applied to input raw data from advertising datasets. Next, fuzzy restricted Boltzmann machine (FRBM) is used to construct the fuzzy deep belief network (FDBN) with the unsupervised method layer by layer. Finally, fuzzy logistic regression (FLR) is utilized for modeling the CTR. The experimental results show that the proposed FDNN model outperforms several baseline models in terms of both data representation capability and robustness in advertising click log datasets with noise.</p></div
General Rules for Optical Activity in Light Scattering of Plasmonic Nanostructures
We
study the general properties of optical activity of plasmonic
nanostructures in theory using the eigenmode technique for light-scattering
problem. Explicit formulas for the optical rotational strengths associated
with the resonance modes and their sum rule are derived for plasmonic
nanostructures. Moreover, relations between symmetry and optical activity
are discussed. How optical activity arises from symmetry breaking
is investigated by introducing dissymmetric parts to a symmetric achiral
nanostructure, and a linear dependence of the optical rotational strength
on the volume of dissymmetric parts is revealed. This work not only
establishes a theoretical framework for studying chiral plasmonic
nanostructures but also provides guidelines for tailoring their optical
activities
Study on Enhancement Mechanism of Conductivity Induced by Graphene Oxide for Polypyrrole Nanocomposites
Polypyrrole
(PPy)/graphene oxide (GO) nanosheet composites with
different GO content have been successfully prepared. The morphology,
microstructure, defect property and conducting mechanism were examined
by Raman spectroscopy, Fourier transform infrared spectroscopy (FTIR),
field-emission scanning electron microscope (FE-SEM), X-ray photoelectron
spectra (XPS), positron annihilation technology (PAT), and electrical
conductivity measurements for PPy/GO conducting nanocomposites, respectively.
Experimental results indicated that PPy was deposited onto the GO
surface homogeneously. Four orders of magnitude increase in electrical
conductivity was successfully achieved with small quantities of GO
compared to pristine PPy. In order to elucidate the conducting mechanism,
an electron transfer model was used to describe bipolaronic formation,
which can be confirmed by XPS and positron annihilation parameters
measured including positron annihilation lifetimes, positron annihilation
Doppler broadening spectroscopy (DBS) and continuous distribution
of positron lifetime. Electronic conductivity enhancement can be attributed
to (a) the interfacial interaction between the GO layers and PPy results
in the electron transfer, which leads to the increase of bipolaronic
concentration, and (b) the π–π stacking between
the GO layers and PPy can improve the conjugation degree of the PPy
chains and the longer conjugation length makes the conducting particle
delocalization more easily, leading to the increase in electron mobility.
On the other hand, the continuous conducting network structure of
graphene nanosheets homogeneously dispersed in the PPy matrix and
carriers between localized states formed at the graphene–PPy
interfaces where hopping occurred, also result in increase of conductivity
Lithium Sulfonate/Carboxylate-Anchored Polyvinyl Alcohol Separators for Lithium Sulfur Batteries
A monolayer polyÂ(vinyl alcohol) (PVA)-based
separator with pendant sulfonate/carboxylate groups and compact morphology
is synthesized to suppress the essential lithium polysulfide permeation
in lithium sulfur batteries (LSBs). The Li<sup>+</sup> transference
number is significantly increased to 0.8, much higher than that of
a commercial separator (0.43). The polysulfide retention is verified
by idle test in a polysulfide-rich electrolyte under the internal
electric field of the cell. The LSB with an additive-free electrolyte
attains a Coulombic efficiency around 98% and delivered capacity of
804 mA h g<sup>–1</sup> at 2.5 A g<sup>–1</sup>. After
500 cycles, it retains 901 mA h g<sup>–1</sup> at 1.5 A g<sup>–1</sup> with extra low fading rate of 0.016% per cycle. Overall,
this monolayer PVA-based separator provides a facile and effective
technique to assemble highly stable LSBs