Search

Your search keyword '"Wang, Yuzhen"' showing total 1,681 results
Start Over Author "Wang, Yuzhen"
1,681 results on '"Wang, Yuzhen"'

1. Modulating trap properties by Cr3+-doping in Zn2SiO4: Mn2+ nano phosphor for optical information storage

Author

Yi, Xin, Liu, Hui, Wang, Yihuan, Chen, Junjie, Chen, Zhanglin, Wang, Yuzhen, Yuan, Xuanyi, and Zhu, Kaiming

Subjects
Condensed Matter - Materials Science
Abstract

Photo stimulated luminescent materials are one of the most attractive alternatives for next generation optical information storage technologies. However, there are still some challenges in regulating appropriate energy levels in luminescent materials for optical information storage. Herein, a green emission nanophosphor Zn2SiO4: Cr3+, Mn2+ with the trap depth of 1.05 eV, fulfilling the requirements for optical information storage, was fabricated for the first time through the solution combustion method and subsequent heat treatment at 1000 degree centigrade for 2h. The crystal structure, micromorphology, photoluminescence (PL), photoluminescence excitation (PLE), and afterglow properties of Zn2SiO4: xCr3+, yMn2+ were studied systematically. By applying the strategy of trap depth engineering, high trap density with proper trap depth was observed when Cr3+ ions were introduced into Zn2SiO4: Mn2+. Thermoluminescence (TL) glow curve analysis through the initial rise (IR) method was conducted to gain some insight into the information of traps. As proof of application, information storage was experimentally achieved by choosing 275 nm illumination for information writing and 980 nm NIR excitation for information reading. The results indicate that Zn2SiO4: Cr3+, Mn2+ phosphor holds promise for potential applications in the field of optical information storage.

Published
2024

13. A Study on the Main Obstacles and Improvement Pathways of Subsidizing Education in Private Vocational Colleges

Author

Mo, Huiyin, Yu, Ruiwen, Wang, Yuzhen, Striełkowski, Wadim, Editor-in-Chief, Black, Jessica M., Series Editor, Butterfield, Stephen A., Series Editor, Chang, Chi-Cheng, Series Editor, Cheng, Jiuqing, Series Editor, Dumanig, Francisco Perlas, Series Editor, Al-Mabuk, Radhi, Series Editor, Scheper-Hughes, Nancy, Series Editor, Urban, Mathias, Series Editor, Webb, Stephen, Series Editor, Rad, Dana, editor, Chew, Fong Peng, editor, Hutagalung, Fonny Dameaty, editor, and Birkök, Cüneyt, editor

Published
2024
Full Text
View/download PDF

14. Thermally enhanced photoluminescence and temperature sensing properties of Sc$_2$W$_3$O$_{12}$:Eu$^{3+}$ phosphors

Author

Niu, Yude, Wang, Yuzhen, Zhu, Kaiming, Ye, Wanggui, Feng, Zhe, Liu, Hui, Yi, Xin, Wang, Yihuan, and Yuan, Xuanyi

Subjects
Condensed Matter - Materials Science
Abstract

Currently,lanthanide ions doped luminescence materials applying as optical thermometers have arose much concern. Basing on the different responses of two emissions to temperature, the fluorescence intensity ratio (FIR) technique can be executed and further estimate the sensitivities to assess the optical thermometry performances. In this study, we introduce different doping concentrations of Eu$^{3+}$ ions into negative expansion material Sc$_2$W$_3$O$_{12}$:Eu$^{3+}$, accessing to the thermal enhanced luminescence from 373 to 548 K, and investigate the temperature sensing properties in detail. All samples exhibit good thermally enhanced luminescence behavior. The emission intensity of Sc$_2$W$_3$O$_{12}$: 6 mol% Eu$^{3+}$ phosphors reaches at 147.81% of initial intensity at 473 K. As the Eu doping concentration increases, the resistance of the samples to thermal quenching decreases. The FIR technique based on the transitions 5D0-7F1 (592 nm) and 5D0-7F2 (613 nm) of Eu$^{3+}$ ions demonstrate a maximum relative temperature sensitivity of 3.063% K-1 at 298 K for Sc$_2$W$_3$O$_{12}$:Eu$^{3+}$: 6 mol% Eu$^{3+}$ phosphors. The sensitivity of sample decreases with the increase of Eu$^{3+}$ concentration. Benefiting from the thermal enhanced luminescence performance and good temperature sensing properties, the Sc$_2$W$_3$O$_{12}$:Eu$^{3+}$: Eu$^{3+}$ phosphors can be applies as optical thermometers.

Published
2022
Full Text
View/download PDF

39. Research on international logistics supply chain management strategy based on deep reinforcement learning

Author

Wang Yuzhen and Wang Jian

Subjects
deep reinforcement learning algorithm, supply chain management, dqn algorithm, impact factor, bellman equation, 68t05, Mathematics, QA1-939
Abstract

The use of deep reinforcement learning algorithms for strategy formulation in supply chain management enables the nodes in the supply chain to better improve their management strategies. In this paper, a supply chain model is constructed as a starting point, and deep reinforcement learning algorithms are introduced on this basis. Firstly, the decision problem of uncertainty is handled by the reinforcement learning method of functions, and the DQN algorithm (deep neural network algorithm) is divided into two parts for iterative rules. Then the target network is established to make the iterative process more stable, to improve the convergence of the algorithm, evaluate the loss function in the training process of the network, and to determine its influence factor. Then the neural network is used to improve the iteration rule, improve the output layer, select the final action, and define the model expectation reward. Finally, the Bellman equation is fitted to the function by a deep neural network to calculate the final result. The experimental results show that by analyzing and constructing the cost of international logistics under supply chain management, the capacity utilization rate of ocean freight link is 57% The unloading link is 74% and the total capacity utilization rate is calculated as 76%. It shows that using deep reinforcement learning algorithms under international logistics supply chain management is feasible and necessary for improving the management strategy research of supply chains.

Published
2024
Full Text
View/download PDF

41. Consistency between Functional Constipation Classification by Clinical Symptoms and Colorectal and Anal Functional Examinations

Author

QIN Xiaohan, ZHANG Peiyan, WANG Yuzhen

Subjects
constipation, functional constipation, anorectal manometry, defecography, gastrointestinal transit, diagnosis, differential, Medicine
Abstract

Background The treatment for functional constipation (FC) generally relies on the classification by clinical symptoms, but whether the classification by clinical symptoms is consistent with that by colorectal and anal function examinations still remains unclear. Objective To examine the consistency between FC classification by clinical symptoms and colorectal and anal functional examinations. Methods Forty FC outpatients and inpatients completing colorectal and anal functional examinations in Department of Gastroenterology, Hebei General Hospital from January 2018 to August 2021 were enrolled in this retrospective study. Symptoms were acquired for classifying FC by use of a questionnaire survey, including the frequency of spontaneous defecation per week, shape and type of stool assessed using the Bristol Stool Scale, difficulty in defecation, sense of anorectal blockage during defecation, requirement for manual assistance in defecation, and the frequency and degree of feeling of incomplete evacuation. And the results detected by examinations, including anorectal manometry (ARM) , defecography and gastrointestinal transit time (GITT) were also used for FC classification. The consistency of FC classification by symptoms and the three examinations was assessed. Results The FC classification by symptoms was as follows: slow transit constipation (STC) 〔27.5% (11/40) 〕, defecation disorder constipation〔20.0% (8/40) 〕, mixed constipation〔37.5% (15/40) 〕, and normal-transit constipation (NTC) 〔15.0% (6/40) 〕. FC classified by ARM included defecation disorder constipation〔80.0% (32/40) 〕and NTC〔20.0% (8/40) 〕, and by defecography also only included defecation disorder constipation〔67.5% (27/40) 〕 and NTC 〔32.5% (13/40) 〕. By GITT, FC classification contained three types: STC〔20.0% (8/40) 〕, defecation disorder constipation 〔15.0% (6/40) 〕, and NTC〔65.0% (26/40) 〕. The weighted Kappa test indicated that the FC classification by symptoms was not consistent with that by ARM, defecography or GITT (Kappa=-0.123, P=0.502; Kappa=-0.040, P=0.794; Kappa=-0.140, P=0.215) , and there was no overall consistency between FC classification by symptoms and the three examinations (Kappa=-0.005, P=0.944) . Conclusion Mixed constipation was the major type of FC classified by symptoms, while defecation disorder constipation was the major type of FC classified by the three examinations. As there are differences between clinical symptom classification and examination classification, FC should be diagnosed based on both clinical symptoms and examination results, accompanied with the individualized analysis.

Published
2023
Full Text
View/download PDF

Catalog

Books, media, physical & digital resources
See catalog results