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1.
Networks and Spatial Economics - We revisit a dynamical system for solving variational inequalities. Under strongly pseudomonotone and Lipschitz continuous assumptions of the considered operator,... 相似文献
2.
Buhari Adamu Muhammad Ooi Chee-Pun Baskaran Vishnu Monn Phan Raphael CW Wong KokSheik Tan Wooi-Haw 《Multimedia Tools and Applications》2022,81(7):9151-9176
Multimedia Tools and Applications - The interest in real-time micro-expression recognition has increased with the current trend in human-computer interaction applications. Presently, there are... 相似文献
3.
Anh Tuan Thanh Pham Oanh Kieu Truong Le Dung Van Hoang Truong Huu Nguyen Trang Huyen Cao Pham Phuong Thanh Ngoc Vo Thang Bach Phan Vinh Cao Tran 《Journal of the European Ceramic Society》2021,41(6):3493-3500
Structure modification has been found to tune significantly the transparent-conducting performance, especially mobility and conductivity of hydrogenated Ga-doped ZnO (HGZO) films. The strong correlation between film thickness and mobility of the films is revealed. The mobility increases quickly with increasing the thickness from 350 to 900 nm, and then tends to be saturated at further thicknesses. A higher mobility than 50 cm2/Vs can be achieved, which is an extra-high value for polycrystalline ZnO films deposited by using the sputtering technique. The thickness-dependent mobility originates from scatterings on grain boundaries and dislocation-induced defects controlled by thin-film growth. Based on the Volmer-Weber model, an expansion model is built up to describe the thickness-dependent crystal growth of the HGZO films, especially at the thick films. As a result, the 800 nm-thick HGZO film obtains the highest performance with high mobility of 51.5 cm2/Vs, low resistivity of 5.3 × 10?4 Ωcm, and good transmittance of 83.3 %. 相似文献
4.
Upconversion phosphors are known as a material system that can convert near-infrared light into visible/ultraviolet emissions by sequentially absorbing multiple photons. The studies on upconversion materials often use two rare earth (RE) ions as a sensitizer-activator pair. We investigated the influences on luminescence intensity depending on Cr-doping content (x) of hexagonal NaLu0.98–xCrxF4Er0.02 (x = 0–0.9) upconversion material by substituting Lu3+ ions with Cr3+in the absence of Gd3+. The change in upconversion luminescence intensity appears with saddle-like shape. We suggest that Cr3+ ions play the dual role as a constituent in host lattice and a sensitizer in the upconversion process. Optimal conditions for gaining the strongest upconversion emission correspond to x = 0.3–0.5, where there are effective energy transfers between Cr3+ and Er3+ ions and CrEr dimers. Apart from these values, the emission intensity decreases rapidly which can be ascribed to the absence of multiple-photon absorption for the case of low Cr3+ contents, and to the coupling between Cr3+ and/or Er3+ ions for the case of high Cr3+ contents. Magnetization and electron-spin-resonant measurements were performed to understand the correlation between the optical and magnetic properties. 相似文献
5.
A new strategy for the selective coating of tin sulfide (SnS) on the surface of moth‐eye patterned (MEP) conducting polymer film is studied by considering the optical properties of the antireflective moth‐eye pattern and flexibility of polymer films. The semiconductor SnS is selectively coated on the surface of MEP microdomes of poly(3,4‐ethylenedioxythiophene) poly(styrene‐sulfonate) (PEDOT:PSS) film. The SnS coated MEP film is obtained by using pore selectively SnS thin layer functionalized polystyrene honeycomb‐patterned porous (HCP) film as a template. Aqueous PEDOT:PSS solution is poured on the SnS functionalized HCP films and detached for the fabrication of SnS coated MEP films. The films show a satisfactory photo‐responsive property under solar stimulated light illumination due to the antireflective MEP structure of PEDOT film and homogenous SnS coating on the surface of the conducting polymer. 相似文献
6.
Anastasia A. Ivanova Chi Phan Ahmed Barifcani Stefan Iglauer Alexey N. Cheremisin 《Journal of surfactants and detergents》2020,23(2):327-338
Surfactant flooding has widely been used as one of the chemically enhanced oil recovery (EOR) techniques. Surfactants majorly influence the interfacial tension, γ, between oil and brine phase and control capillary number and relative permeability behavior and, thus, influence ultimate recovery. Additives, such as nanoparticles, are known to affect surfactant properties and are regarded as promising EOR agents. However, their detailed interactions with surfactants are not well understood. Thus, in this work, we examined the influence of silica nanoparticles on the ability of surfactants to lower γ and to increase viscosity at various temperatures and salinities. Results show that the presence of nanoparticles decreased γ between n-decane and various surfactant formulations by up to 20%. It was found that γ of nanoparticles–surfactant solutions passed through a minimum at 35 °C when salt was added. Furthermore, the viscosity of cationic surfactant solutions increased at specific salt (1.5 wt.%) and nanoparticle (0.05 wt.%) concentrations. Results illustrate that selected nanoparticles–surfactant formulations appear very promising for EOR as they can lower brine/n-decane interfacial tension and act as viscosity modifiers of the injected fluids. 相似文献
7.
Duong Huan Thanh Phan Hieu Chi Tran Tu Minh Dhar Ashutosh Sutra 《Neural computing & applications》2021,33(23):16425-16437
Neural Computing and Applications - Predicting the critical buckling loads of functionally graded material (FGM) plates using an analytical method requires solving complex equations with various... 相似文献
8.
Truong Phuong Phan Alex Truong Buu Suen Benjamin Melles Gerrit Talke Frank 《Microsystem Technologies》2020,26(11):3403-3407
Microsystem Technologies - A low-cost, self-imaging smartphone attachment has been developed for remote slit lamp examination of the human eye. The device is designed with off-the-shelf optical... 相似文献
9.
Phan Han Duy Ellis Kirsten Barca Jan Carlo Dorin Alan 《Neural computing & applications》2020,32(2):567-588
Neural Computing and Applications - Parameter settings for nature-inspired optimization algorithms are essential for their effective performance. Evolutionary algorithms and swarm intelligence... 相似文献
10.
Ho Kim Dan Nguyen Minh Ty Dacheng Zhou Jianbei Qiu Anh-Luan Phan 《Journal of the American Ceramic Society》2020,103(11):6356-6368
In this paper, we study the influence of Cr3+ on yellowish-green upconversion (UC) emission and the energy transfer (ET) of Er3+/Cr3+/Yb3+ tri-doped in SiO2–ZnO–Na2O–La2O3 (SZNL) zinc silicate glasses under excitation of the 980 nm laser diode (LD). The influence of Cr3+ on enhancing the red UC emission of Er3+/Cr3+/Yb3+ tri-doped in SiO2–ZnO–Na2O–La2O3 zinc silicate glasses under the excitation of 980nm LD was also investigated. The ET processes between Yb3+, Cr3+, and Er3+, together with the combination of Yb3+-Cr3+-Er3+, which led to the green UC emission intensity of Er3+/Cr3+/Yb3+ tri-doped in SiO2–ZnO–Na2O–La2O3 zinc silicate glasses bands centered at ~546 nm have been significantly enhanced. By increasing the concentration of Cr3+ from 0 up to 5 mol.%, we can locate the Commission Internationale de l'éclairage (CIE) 1931 (x; y) chromaticity coordinates for UC emissions of Er3+/Cr3+/Yb3+ tri-doped in the central position of the yellowish-green color region of CIE 1931 chromaticity diagram. Besides, the ET processes between the Yb3+, Cr3+, and Er3+ are also proposed and discussed. 相似文献