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Structure and photoluminescence properties of Er^(3+)-doped TiO_2-SiO_2 powders prepared by sol-gel method

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Chinese Physics B 2011年第8期20卷 429-434页

作者：赵建果张伟英马紫微谢二庆赵阿可刘照军 college of Physics and electronic information Luoyang Normal College School of physical Science and Technology Lanzhou University

Er3＋-doped TiO2-SiO2 powders are prepared by the sol-gel method, and they are characterized by high resolution transmission electron microscopy （HR-TEM）, X-ray diffraction （XRD） spectra, and Raman spectra of the samples. It is shown that the TiO2 nanocrystals are surrounded by an SiO2 glass matrix. The photoluminescence （PL） spectra are recorded at room temperature. A strong green luminescence and less intense red emission are observed in the samples when they are excited at 325 nm. The intensity of the emission, which is related to the defect states, is strongest at the annealing temperature of 800℃. The PL intensity of Er3＋ ions increases with increasing Ti/Si ratio due to energy transfer between nano-TiO2 particles and Er3＋ ions.

关键词： TiO2-SiO2 sol-gel Raman photoluminescence

A novel active-passive protection strategy endows carbonyl iron with excellent intelligent anti-corrosion and microwave absorption dual functional characteristics

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Nano Research 2025年第1期18卷 487-500页

作者： Wei Tian Quanyuan Feng Linbo Zhang Yinfan Liu Xian Jian Longjiang Deng Institute of Microelectronics School of Information Science and TechnologySouthwest Jiaotong UniversityChengdu 611756China National Engineering Researching Centre of Electromagnetic Radiation Control Materials Key Laboratory of Multi-Spectral Absorbing Materials and Structures of Ministry of EducationState Key Laboratory of Electronic Thin Films and Integrated DevicesSchool of Electronic Science and EngineeringUniversity of Electronic Science and Technology of ChinaChengdu 611731China School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 611731China The Yangtze Delta Region Institute(Huzhou)&School of electronic Science and Engineering University of Electronic Science and Technology of ChinaHuzhou 313001China

Carbonyl iron absorbers(CI)face significant challenges in practical applications,such as corrosion,interface bonding failure,detachment,and high maintenance ***,we have developed intelligent self-healing technology based on proactive/passive mechanisms via in situ synthesis of self-healing factors(polydopamine/benzotriazole(PDA/BTA))and physical barrier layers(SiO_(2)/1,1,1,3,3,3-hexamethyl disilazane,SiO_(2)/HMDS)to enhance corrosion resistance,while also being compatible with efficient microwave absorption *** unique multiscale structure gives full play to the utilization of the roles of each functional layer,including the intelligent self-healing features of PDA/BTA,physical shielding and spatial confinement characteristics of SiO_(2)/HMDS,and magnetic-dielectric synergistic mechanism resulted from the good impedance matching characteristics,the conduction loss,the interfacial polarization loss and natural *** asfabricated composites achieved an exceptional minimum reflection loss value of-55.4 dB at 10.7 GHz and the effective absorption band of 7.6 ***,it still exhibits obvious self-healing and corrosion resistance characteristics after 360 h corrosion treatment,ascribed to the self-healing mechanism of PDA/BTA and the blocking intervention effect of SiO_(2)/*** work is considered to pave the way for the synthesis of high-performance magnetic absorbers,especially in enhancing their intelligent self-healing ability in corrosive environments.

关键词： microwave absorption intelligent self-healing technology carbonyl iron multiscale structure magneticdielectric synergistic mechanism

Dispersion characteristics of a slow wave structure with a modified photonic band gap

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Chinese Physics B 2011年第3期20卷 129-134页

作者：高喜杨梓强曹卫平姜彦南 School of physical electronics University of Electronic Science and Technology of China information and Communication college Guilin University of Electronic Technology

This paper studies the dispersion characteristics of a modified photonic band-gap slow-wave structure with an open boundary by simulation and experiment. A mode launcher with a wheel radiator and a coupling probe is presented to excite a pure TM01-like mode. The cold test and simulation results show that the TM01-like mode is effectively excited and no parasitic modes appear. The dispersion characteristics obtained from the cold test are in good agreement with the calculated results.

关键词： modified photonic band-gap slow-wave structure TM01-like mode cold test

A Novel Self-Supervised Learning Network for Binocular Disparity Estimation

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 209-229页

作者： Jiawei Tian Yu Zhou Xiaobing Chen Salman A.AlQahtani Hongrong Chen Bo Yang Siyu Lu Wenfeng Zheng Department of Computer Science and Engineering Major in Bio Artificial IntelligenceHanyang UniversityAnsan-si15577Republic of Korea School of Electrical and Computer Engineering Louisiana State UniversityBaton RougeLA 70803USA Department of Computer Engineering College of Computer and Information SciencesKing Saud UniversityRiyadh11574Saudi Arabia School of Automation University of Electronic Science and Technology of ChinaChengdu610054China

Two-dimensional endoscopic images are susceptible to interferences such as specular reflections and monotonous texture illumination,hindering accurate three-dimensional lesion reconstruction by surgical *** study proposes a novel end-to-end disparity estimation model to address these *** approach combines a Pseudo-Siamese neural network architecture with pyramid dilated convolutions,integrating multi-scale image information to enhance robustness against lighting *** study introduces a Pseudo-Siamese structure-based disparity regression model that simplifies left-right image comparison,improving accuracy and *** model was evaluated using a dataset of stereo endoscopic videos captured by the Da Vinci surgical robot,comprising simulated silicone heart sequences and real heart video *** results demonstrate significant improvement in the network’s resistance to lighting interference without substantially increasing ***,the model exhibited faster convergence during training,contributing to overall performance *** study advances endoscopic image processing accuracy and has potential implications for surgical robot applications in complex environments.

关键词： Parallax estimation parallax regression model self-supervised learning Pseudo-Siamese neural network pyramid dilated convolution binocular disparity estimation

A novel optical beam splitter based on photonic crystal with hybrid lattices

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Chinese Physics B 2012年第6期21卷 307-310页

作者：朱清溢付永启胡德清章志敏 School of physical electronics University of Electronic Science and Technology of China Department of electronic Engineering Sichuan Information Technology College

A novel optical beam splitter constructed on the basis of photonic crystal（PC） with hybrid lattices is proposed in this *** band gap of square-lattice PC is so designed that the incident light is divided into several branch ***-lattice graded-index PCs are combined for focusing each *** calculations are carried out on the basis of finite-different time-domain algorithm to prove the feasibility of our *** waveguide is unnecessary in the *** the device has functions of both splitting and focusing *** of the divided beam at site of full-width at half-maximum is of the order of λ/*** designed splitter has the advantages that it has a small volume and can be integrated by conventional semiconductor manufacturing process

关键词： optical beam splitter photonic crystals hybrid lattices finite-different time-domainmethod

Controlling the transition between Turing and antispiral patterns by using time-delayed-feedback

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Chinese Physics B 2012年第3期21卷 304-309页

作者：贺亚峰刘富成范伟丽董丽芳 Hebei Key Laboratory of Optic-electronic information Materials College of Physical Science and TechnologyHebei University

The controllable transition between Turing and antispiral patterns is studied by using a time-delayed-feedback strategy in a FitzHugh-Nagumo model. We treat the time delay as a perturbation and analyse the effect of the time delay on the Turing and Hopf instabilities near the Turing Hopf codimension-two phase space. Numerical simulations show that the transition between the Turing patterns （hexagon, stripe, and honeycomb）, the dual-mode antispiral, and the antispiral by applying appropriate feedback parameters. The dual-mode antispiral pattern originates from the competition between the Turing and Hopf instabilities. Our results have shown the flexibility of the time delay on controlling the pattern formations near the Turing-Hopf codimension-two phase space.

关键词： pattern formation Turing-Hopf bifurcations time delay

Exact solutions of (3+1)-dimensional nonlinear incompressible non-hydrostatic Boussinesq equations

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Chinese Physics B 2013年第5期22卷 83-90页

作者：刘萍李子良 college of Electron and information Engineering University of Electronic Science and Technology of China Zhongshan Institute physical Oceanography Laboratory College of Physical and Environment OceanographyOcean University of China

The symmetries and the exact solutions of the （3＋l）-dimensional nonlinear incompressible non-hydrostatic Boussi- nesq （INHB） equations, which describe atmospheric gravity waves, are studied in this paper. The calculation on symmetry shows that the equations are invariant under the Galilean transformations, the scaling transformations, and the space-time translations. Three types of symmetry reduction equations and similar solutions for the （3＋ 1）-dimensional INHB equations are proposed. Traveling and non-traveling wave solutions of the INHB equations are demonstrated. The evolutions of the wind velocities in latitudinal, longitudinal, and vertical directions with space-time are demonstrated. The periodicity and the atmosphere viscosity are displayed in the （3＋1）-dimensional INHB system.

关键词： (3+1)-dimensional nonlinear incompressible non-hydrostatic Boussinesq equations atmosphericgravity waves symmetries exact solutions

Throughput and BER of wireless powered DF relaying in Nakagami-m fading

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Science China(information Sciences) 2017年第10期60卷 204-216页

作者： Yan GAO Yunfei CHEN Aiqun HU School of electronic information Nanjing College of Information Technology college of Computer and information Hohai University college of information Science and Engineering Southeast University

Energy harvesting provides a promising solution to the extra energy requirement at the relay due to relaying. In this paper, the throughput and bit error rate of a decode-and-forward relaying system are studied using power splitting wireless power. Three different transmission scenarios are considered: instantaneous transmission, delay-or error-constrained transmission and delay-or error-tolerant transmission. For each scenario,exact expressions for the throughput and bit error rate are derived. Numerical results show that, for instantaneous transmission, the optimum splitting factor is not sensitive to the channel gain of the source-to-relay *** delay-or error-constrained transmissions, the optimum splitting factor increases with the quality of the source-to-relay link and decreases with the quality of the relay-to-destination link. For delay-or error-tolerant transmissions, the optimum splitting factor is insensitive to the quality of the source-to-relay link.

关键词： decode-and-forward energy harvesting power-splitting relaying

Service-Oriented Wireless Multimedia Multicasting with Partial Frequency Reuse

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Tsinghua Science and Technology 2016年第6期21卷 598-609页

作者： Quanxin Zhao Liang Xu Yuming Mao Supeng Leng Geyong Min Jia Hu Noushin Najjari the School of Communication and information Engineering University of Electronic Science and Technology of China the college of Engineering Mathematics and Physical Sciences University of Exeter

Service-Oriented Architecture（SOA） is employed in a wide range of applications because it promises to expose computation-intensive tasks as services and combine them with new applications to accelerate their applications development process. For service-oriented multimedia applications, the performance of multicasting transmission services under multimedia traffic must be evaluated. Multiview Video（MVV） is a promising and emerging type of multimedia traffic that consists of multiple video streams, allows stream switching, and requires strict Quality-of-Service（Qo S）. In this study, we investigated multicast transmission of MVV in wireless cellular networks with Partial Frequency Reuse（PFR） and focused on two challenging problems：（1） multicast group formation and（2） subchannel and power allocation. Initially, we propose a novel Content-based Partial frequency reuse Diversity Grouping（CPDG） scheme to allocate users to multicast groups on the basis of Partial frequency reuse Diversity（PD） in wireless networks with PFR. After group formation, an optimization problem for subchannel and power allocation is formulated to minimize network power consumption under Qo S constraint. Thereafter,the optimization problem is divided into two subproblems and solved using simplex method and Karush-KuhnTucker（KKT） condition. Finally, to solve the optimization problem, a suboptimal scheme referred to as Partial frequency reuse Diversity Based Energy-efficient Multicasting（PDEM） is proposed by dynamically allocating wireless resources under Qo S constraint. The simulation results show that the proposed PDEM scheme can achieve close-to-optimal performance. Moreover, mathematical analysis of the effect of PD on network performance can provide guidelines for optimization of multimedia traffic in multicasting-enabled wireless cellular networks with PFR.

关键词： service-oriented multimedia multicast quality-of-service frequency reuse diversity