An Intelligent Framework of Oral Examination System under Network Environment and Its Application

Weifeng MA,Xiaoyong SUN 보안공학연구지원센터 2014 International Journal of Multimedia and Ubiquitous Vol.9 No.12

As a crucial step in the process of teaching and training, examination, especially oral examination, is characterized with such defects as excessive subjectivity, difficult organization, low efficiency and heavy pressure. Thus, network technology and computer technology are employed to further promote the informationization of traditional oral examination. Through analyzing the existing problems of traditional oral examination and the feasibility of oral examination under network environment, this paper puts forward a universal framework and management model for oral examination under network environment and designed an oral examination system based on digital voice technology, artificial intelligence and software engineering. The research findings have been applied to mandarin Chinese test. So far Over 10 organization users have adopted the system and more than 300,000 examinees have been tested. Viewed from the practice, expected effects have been achieved.

Highly-sensitive Detection of Salvianolic Acid B using Alumina Microfibers-modified Electrode

Sun, Dong,Zheng, Xiaoyong,Xie, Xiafeng,Yang, Xiaofeng,Zhang, Huajie Korean Chemical Society 2013 Bulletin of the Korean Chemical Society Vol.34 No.11

Alumina microfibers with porous structures were prepared through hydrothermal reaction, and then used to modify the surface of carbon paste electrode (CPE). After modification with alumina microfibers, the electrochemical activity of CPE was found to be greatly improved. On the surface of alumina microfibers-modified CPE, the oxidation peak current of salvianolic acid B, a main bioactive compound in Danshen with anti-oxidative and anti-inflammatory effects, was remarkably increased compared with that on the bare CPE surface. The influences of pH value, amount of alumina microfibers and accumulation time were studied. Based on the strong signal amplification effects of alumina microfibers, a novel electrochemical method was developed for the detection of salvianolic acid B. The linear range was from 5 ${\mu}gL^{-1}$ to 0.3 mg $L^{-1}$, and the detection limit was 2 ${\mu}gL^{-1}$ (2.78 nM) after 1-min accumulation. The new method was successfully used to detect salvianolic acid B in ShuangDan oral liquid samples, and the recovery was over the range from 97.4% to 102.9%.

Realizing highly efficient multicolor tunable emissions from Tb³⁺ and Eu³⁺ co-doped CaGd₂(WO₄)₄ phosphors via energy transfer by single ultraviolet excitation for lighting and display applications

Huang, Xiaoyong,Li, Bin,Du, Peng,Guo, Heng,Cao, Renping,Yu, Jae Su,Wang, Kai,Sun, Xiao Wei Elsevier 2018 Dyes and pigments Vol.151 No.-

<P><B>Abstract</B></P> <P>In this paper, we reported on multicolor emission tuning in Tb<SUP>3+</SUP> and Eu<SUP>3+</SUP> co-doped CaGd<SUB>2</SUB>(WO<SUB>4</SUB>)<SUB>4</SUB> phosphors prepared by a traditional high-temperature solid-state reaction. Upon 380 nm ultraviolet excitation, the emission color of CaGd<SUB>2</SUB>(WO<SUB>4</SUB>)<SUB>4</SUB>:Tb<SUP>3+</SUP>,Eu<SUP>3+</SUP> phosphors can be readily tuned from green to yellow, orange and finally to pure red through varying the concentration ratio of Eu<SUP>3+</SUP> and Tb<SUP>3+</SUP> ions. The energy transfer mechanism from Tb<SUP>3+</SUP> to Eu<SUP>3+</SUP> was systematically investigated by photoluminescence spectra, luminescence decay times, and time-resolved spectra. The internal quantum efficiencies of these phosphors were measured, and their thermal stability was also studied. A prototype white light-emitting diode (LED) device was fabricated by using an ultraviolet chip combined with a blend of blue-emitting BaMgAl<SUB>10</SUB>O<SUB>l7</SUB>:Eu<SUP>2+</SUP> phosphors, green-emitting BaSrSiO<SUB>4</SUB>:Eu<SUP>2+</SUP> phosphors, and red-emitting CaGd<SUB>2</SUB>(WO<SUB>4</SUB>)<SUB>4</SUB>:50%Tb<SUP>3+</SUP>,50%Eu<SUP>3+</SUP> phosphors. All the results indicate that the CaGd<SUB>2</SUB>(WO<SUB>4</SUB>)<SUB>4</SUB>:Tb<SUP>3+</SUP>,Eu<SUP>3+</SUP> has great potential application in lighting and displays.</P> <P><B>Highlights</B></P> <P> <UL> <LI> CaGd<SUB>2</SUB>(WO<SUB>4</SUB>)<SUB>4</SUB>:Tb<SUP>3+</SUP>,Eu<SUP>3+</SUP> showed efficient energy-transfer from Tb<SUP>3+</SUP> to Eu<SUP>3+</SUP>. </LI> <LI> CaGd<SUB>2</SUB>(WO<SUB>4</SUB>)<SUB>4</SUB>:Tb<SUP>3+</SUP>,Eu<SUP>3+</SUP> exhibited tunable color emission under 380 nm excitation. </LI> <LI> The energy-transfer mechanism was studied in detail. </LI> <LI> Quantum efficiency and thermal stability were investigated. </LI> <LI> The proof-of-concept LED lamps were fabricated by employing phosphors and UV LEDs. </LI> </UL> </P> <P><B>Graphical abstract</B></P> <P>[DISPLAY OMISSION]</P>

Highly-sensitive Detection of Salvianolic Acid B using Alumina Microfibers-modified Electrode

Dong Sun,Xiaoyong Zheng,Xiafeng Xie,Xiaofeng Yang,Huajie Zhang 대한화학회 2013 Bulletin of the Korean Chemical Society Vol.34 No.11

Alumina microfibers with porous structures were prepared through hydrothermal reaction, and then used to modify the surface of carbon paste electrode (CPE). After modification with alumina microfibers, the electrochemical activity of CPE was found to be greatly improved. On the surface of alumina microfibersmodified CPE, the oxidation peak current of salvianolic acid B, a main bioactive compound in Danshen with anti-oxidative and anti-inflammatory effects, was remarkably increased compared with that on the bare CPE surface. The influences of pH value, amount of alumina microfibers and accumulation time were studied. Based on the strong signal amplification effects of alumina microfibers, a novel electrochemical method was developed for the detection of salvianolic acid B. The linear range was from 5 μg L−1 to 0.3 mg L−1, and the detection limit was 2 μg L−1 (2.78 nM) after 1-min accumulation. The new method was successfully used to detect salvianolic acid B in ShuangDan oral liquid samples, and the recovery was over the range from 97.4% to 102.9%.

Carbon Nanotube Paper as Anode for Flexible Lithium-Ion Battery

Xiaogang Sun,Zhenhong Liu,Neng Li,Xiaoyong Wu,Yanyan Nie,Zhipeng Pang,Lifu Yue,Hao Tang 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2016 NANO Vol.11 No.11

In this investigation, multiwalled carbon nanotube (MWCNT) paper consists of MWCNTs and cellulose was fabricated by traditional paper-making method. It was applied directly as negative electrode in flexible lithium ion battery to replace ordinary electrode which is combined with anode material and current collector. The electrochemical performances of the as-produced MWCNT paper (AMP) and carbonized MWCNT paper (CMP) were evaluated in this study. The morphology and structure of the MWCNT papers were observed by scanning electron microscopy (SEM). The electrochemical performance of the battery was operated by cell test and electrochemical impedance spectroscopy (EIS) measurement. The charging and discharging results indicated that the CMP behaves with higher capacity than AMP. And the EIS analysis showed that a lower charge transfer resistance can be obtained in the CMP. The excellent electrochemical performance verifies the feasibility of MWCNT papers as a promising candidate for the anode in flexible lithium ion battery.

Preparation and Hydrogen Barrier Property of FexAly/Al/Al2O3 Composite Coating on X80 Steel Surface

Bingying Wang,Xiaoyong Sun,Enyang Liu,Lin Liu,Wenjuan Ma,Yuze Shi,Peng Huang,Yun Luo 대한금속·재료학회 2024 METALS AND MATERIALS International Vol.30 No.1

Hydrogen-induced embrittlement is a significant safety concern for steel pipelines used in the transmission of hydrogenblendednatural gas. To mitigate this issue, hydrogen barrier coatings can be applied to the surface of steel substrates toreduce hydrogen permeation. In this study, rare earth oxides were optimized via first-principles calculations to identify themost effective doping agents. Subsequently, a FexAly/Al/Al2O3 composite coating doped with La2O3and Ce2O3was successfullyapplied to the surface of X80 steel using hot-dip aluminum plating combined with anodic oxidation. The coatingwas characterized using various techniques, including SEM, EDS, XRD, XPS, and hydrogen permeation tests. The resultsdemonstrated that co-doping La2O3and Ce2O3resulted in a lower adsorption energy of Al2O3to hydrogen molecules, andimproved the surface quality of the aluminizing layer and the composite coating. Electrochemical hydrogen permeationtests showed that the FexAly/Al/Al2O3 composite coating significantly improved the hydrogen barrier property of X80 steel. The anodizing current density was found to have a significant effect on the coating's morphology, which in turn affected thehydrogen barrier property of the coating. The composite coating obtained at an anodizing current density of 2 A/dm2 wasuniform and dense, without noticeable defects, and exhibited the best hydrogen barrier property.

Research on load sharing performance of wind turbine gearbox involving multiple-errors and tooth crack

Fuqi Xie,Yunyun Sun,Shijing Wu,Qiang Zhang,Xiaoyong Li 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.9

The current research on wind turbine gearboxes (WTG) considering multiplefactors influence mainly focuses on dynamic response. However, load sharing performance (LSP) is also extremely important for gear transmission system reliability. In this paper, considering the comprehensive effects of manufacturing errors, assembly errors, clearance floating between stages, mesh stiffness and time-varying load, a coupled translation-torsion dynamic model for WTG was developed to study the LSP. Based on the amplitude variations of timevarying mesh stiffness caused by tooth crack, an approach is provided to introduce the tooth crack into the dynamic model. The results indicate the LSP is mostly sensitive to multiple-errors and severe tooth crack, followed by the time-varying load. The LSP of a system is periodically affected by tooth crack, and the fluctuation ranges increase with the crack growth. Furthermore, the crack of sun gear has greater influence on LSP than that of planet and ring gear.

Design of Layered Aerospace Time Synchronization Architecture and Time Synchronization Links Budget Comparison

Huang Feijiang,Li Xiaoyong,Sun Liping,Sheng wang,Zhang Wenxi,Liu Guangcan 보안공학연구지원센터 2013 International Journal of Future Generation Communi Vol.6 No.6

ILBA: An Improved Bat Algorithm with Inertia Weight Factor and Lévy Flight

Ma weifeng,Shi Hao,Sun Xiaoyong 보안공학연구지원센터 2016 International Journal of Multimedia and Ubiquitous Vol.11 No.10

Aiming at such shortcomings of traditional Bat algorithm as low precision convergence, premature convergence, slow convergence, an improved BA based on inertia weight factor and Lévy flight (ILBA) has been proposed, which has made two modifications on update equations of bat flying position in BA, using inertia weight factor to keep the flight inertia of bat individual, adaptively adjust the exploitation mechanism of the algorithm in different iteration periods, make the algorithm achieve better convergence precision and altering the strategy about position update of bats from Brownian random walks into Lévy flights strategy to effectively avoid local optimism of the algorithm and guarantee its exploration mechanism while taking advantage of heavy-tailed effect of Lévy flight to speed up the convergence. By means of 4 typical test functions simulation, the results show that ILBA boasts faster convergence and superior optimal performance compared to traditional BA and LBA.

Small Non-coding Transfer RNA-Derived RNA Fragments (tRFs): Their Biogenesis, Function and Implication in Human Diseases

Fu, Yu,Lee, Inhan,Lee, Yong Sun,Bao, Xiaoyong Korea Genome Organization 2015 Genomics & informatics Vol.13 No.4

tRNA-derived RNA fragments (tRFs) are an emerging class of non-coding RNAs (ncRNAs). A growing number of reports have shown that tRFs are not random degradation products but are functional ncRNAs made of specific tRNA cleavage. They play regulatory roles in several biological contexts such as cancer, innate immunity, stress responses, and neurological disorders. In this review, we summarize the biogenesis and functions of tRFs.