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The Spatial Effects of Antenna Configuration in a Large Area Inductively Coupled Plasma System for Flat Panel Displays

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Plasma science and Technology 2014年第8期16卷 758-766页

作者： Seon-Geun OH Young-Jun LEE Jae-Hong JEON Jong-Hyeon SEO Hee-Hwan CHOE School of electronics Telecommunication and Computer EngineeringKorea Aerospace University department of Material science and engineering Korea Aerospace University

Spatial distributions of plasma parameters such as electron density, electron temperature and electric potential were investigated using a commercial simulation software （COMSOLTM） to predict the effects of antenna configuration in a large area inductively cou- pled plasma （ICP） system for flat panel displays. Nine planar antenna sets were evenly placed above a ceramic window. While the electron density was influenced by both the input current and gas pressure, the electron temperature and electric potential were dominantly affected by the gas pressure.

关键词： plasma ICP antenna configuration simulation

Orthogonal Codes-Based Dynamic Spectrum Access in Cognitive Radio Networks

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China Communications 2019年第12期16卷 34-46页

作者： Ehab F.Badran Amr A.Bashir Amira I.Zaki Waleed K.Badawi department of electronics and Communications engineering Arab Academy for Science Technology and Maritime Transport

Dynamic spectrum access(DSA) in cognitive radio(CR) networks became a challenging research area recently. In CR technology, the DSA between primary users(PUs) and secondary users(SUs) simultaneously can be achieved without degrading the performance of the PUs by SUs interference. This can be achieved by donating incentive power to the PUs in order to compensate the interference caused by the SUs. Consequently, PUs allow SUs to share the spectrum. In this paper, orthogonal codes-based dynamic spectrum access(OC-DSA) technique is proposed. OC-DSA technique employs orthogonality between PUs and SUs transmitted data symbols in addition to the incentive power donation. Compared to other techniques, the proposed technique uses a simple encoder at the SU network for the same PU network infrastructure. By applying orthogonal codes, the interference caused by SUs is canceled and hence the donated power to incentivize the PUs is reduced. Also, the SU packet rate is increased significantly. The simulation results show that the proposed technique provides effective improvements over other existing techniques in the signal strength and the bit error rate performance of both the PU network and the SU network at the receiver side. Moreover, the proposed technique requires less donated power to incentivize the PU and has higher packet rate.

关键词： cognitive radio dynamic spectrum access orthogonal codes

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金属主链高分子:概念、进展与展望（英文）

science China Materials 2025年第1期 105-109页

作者：张义锋曾凯雯彭慧胜 State Key Laboratory of Molecular engineering of Polymers Department of Macromolecular Science Institute of Fiber Materials and Devices and Laboratory of Advanced Materials Fudan University

金属主链高分子是一类完全以金属原子作为主链的新材料,有望在材料领域开创出一个全新的研究领域.本文重点介绍了金属主链高分子的概念、合成、结构、性能与应用情况,诠释了金属主链高分子广阔的发展前景.本文也总结介绍了金属主链高分...

金属主链高分子是一类完全以金属原子作为主链的新材料,有望在材料领域开创出一个全新的研究领域.本文重点介绍了金属主链高分子的概念、合成、结构、性能与应用情况,诠释了金属主链高分子广阔的发展前景.本文也总结介绍了金属主链高分子在发展过程中面临的挑战和未来的发展方向.

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Lower temperature synthesis of cerium-doped polycrystalline lutetium pyrosilicate powders by a novel sol-gel processing

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science China(Technological sciences) 2014年第8期57卷 1610-1615页

作者： FAN LingCong XU Jian SHI Ying XIE JianJun LEI Fang department of electronics and Information Materials School of Materials Science and EngineeringShanghai University

A novel sol-gel processing was developed to synthesize polycrystalline cerium-doped lutetium pyrosilicate （Lu2Si2O7Ce, LPS ：Ce） powders under low temperature. It was found that the addition of propylene oxide （PPO） could promote the formation of Lu-O-Si bonds in precursor, which was beneficial to the formation of LPS phase. X-ray diffraction （XRD） patterns indicated that the single-phased LPS powder was well crystallized at 1050℃. Microstructure observation demonstrated that the synthetic LPS powder was composed of ellipsoidal grains with the mean size of 40 nm. The luminescent properties were characterized by photoluminescence （PL）, X-ray excited luminescence （XEL） and vacuum ultraviolet （VUV） spectroscopy at room temperature. The synthetic LPS：Ce powder emitted a broad emission spectrum centered at about 380 nm, which should be ascribed to the 5d→4f transition of Ce3＋. Decay time of the synthetic LPS：Ce powder was measured to be only 32 ns.

关键词： lutetium pyrosilicate sol-gel synthesis luminescence

Kinetic theory of (2+4)-level atom in σ^+ σ^-laser fields

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Chinese Physics B 2009年第8期18卷 3395-3403页

作者：于闯于得水陈景标 Institute of Quantum electronics School of Electronics Engineering & Computer SciencePeking University

The kinetic theory of （2＋4）-level atoms in σ^＋ -σ^- laser fields is presented. We systemically discuss friction coefficient, momentum diffusion tensor and atomic temperature based on the Fokker-Planck equation. This cooling system is much like that of a （1＋3）-level atom, and the temperature is still limited to the Doppler temperature. Since this cooling system has not been investigated before, this work may be regarded as a necessary complement to the laser cooling theory.

关键词： laser cooling Fokker-Planck equation quantum optics

A novel radio frequency coil for veterinary magnetic resonance imaging system

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Chinese Physics B 2010年第7期19卷 408-413页

作者：孟斌黄开文王为民 Institute of Quantum electronics School of Electronics Engineering and Computer SciencePeking University

In this article, a novel designed radio frequency （RF） coil is designed and built for the imaging of puppies in a V-shape permanent magnetic resonance imaging （MRI） system. Two sets of Helmholtz coil pairs with a V-shape structure are used to improve the holding of an animal in the coil. The homogeneity and the sensitivity of the RF field in the coil are analysed by theoretical calculation. The size and the shape of the new coil are optimized and validated by simulation through using the finite element method （FEM）. Good magnetic resonance （MR） images are achieved on a shepherd dog.

关键词： veterinary magnetic resonance imaging (MRI) radio frequency (RF) coil homogeneity,receiving sensitivity

Intrusion Detection System for Big Data Analytics in IoT Environment

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Computer Systems science & engineering 2022年第10期43卷 381-396页

作者： M.Anuradha G.Mani T.Shanthi N.R.Nagarajan P.Suresh C.Bharatiraja department of Computer science and engineering St.Joseph’s College of EngineeringChennai600119India department of Computer science and engineering University College of Engineering ArniThatchur632326India department of electronics&Communication engineering Kings College of EngineeringPudukkottai613303India department of electronics&Communication engineering K.Ramakrishnan College of EngineeringTiruchirapalli621112India department of Computer science and engineering KPR Institute of Engineering and TechnologyCoimbatore641407India department of Electrical and electronics engineering SRM Institute of Science and TechnologyChennai603203India

In the digital area,Internet of Things(IoT)and connected objects generate a huge quantity of data traffic which feeds big data analytic models to discover hidden patterns and detect abnormal *** IoT networks are popular and widely employed in real world applications,security in IoT networks remains a challenging *** intrusion detection systems(IDS)cannot be employed in IoT networks owing to the limitations in resources and ***,this paper concentrates on the design of intelligent metaheuristic optimization based feature selection with deep learning(IMFSDL)based classification model,called IMFSDL-IDS for IoT *** proposed IMFSDL-IDS model involves data collection as the primary process utilizing the IoT devices and is preprocessed in two stages:data transformation and data *** manage big data,Hadoop ecosystem is ***,the IMFSDL-IDS model includes a hill climbing with moth flame optimization(HCMFO)for feature subset selection to reduce the complexity and increase the overall detection ***,the beetle antenna search(BAS)with variational autoencoder(VAE),called BAS-VAE technique is applied for the detection of intrusions in the feature reduced *** BAS algorithm is integrated into the VAE to properly tune the parameters involved in it and thereby raises the classification *** validate the intrusion detection performance of the IMFSDL-IDS system,a set of experimentations were carried out on the standard IDS dataset and the results are investigated under distinct *** resultant experimental values pointed out the betterment of the IMFSDL-IDS model over the compared models with the maximum accuracy 95.25%and 97.39%on the applied NSL-KDD and UNSW-NB15 dataset correspondingly.

关键词： Big data cybersecurity IoT networks intrusion detection deep learning metaheuristics intelligent systems

Targets capture by distributed active swarms via bio-inspired reinforcement learning

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science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 210-221页

作者： Kun Xu Yue Li Jun Sun Shuyuan Du Xinpeng Di Yuguang Yang Bo Li Institute of Biomechanics and Medical engineering Applied Mechanics Laboratory Department of Engineering MechanicsTsinghua University Institute of Nuclear and New Energy Technology Tsinghua University Shanghai Aerospace Control Technology Institute Shanghai Key Laboratory of Aerospace Intelligent Control Technology College of Automation engineering Nanjing University of Aeronautics and Astronautics

Natural swarms arranged from cells to herds are usually decentralized but display intriguing collective intelligence in coordinating individuals across large scales to efficiently achieve their common goals. Learning from nature may provide new strategies for controlling collective dynamics of synthetic swarms to accomplish specific functions. Here, we present a bioinspired computational framework that steers distributed active swarms to collectively capture and merge targets via reinforcement learning. We exploit collective milling structures of natural herds to cage the targets, and adopt a switching control policy inspired by sperms' chiral dynamics to optimize the trajectories of individuals, through which the active swarms can selforganize to enclose single or multiple distant targets in a dynamical, adaptive and scalable manner. There exists a critical swarm size, beyond which the excessive competition between agents would generate large mechanical forces, leading to capture instability but enabling the transition from short-distance to long-distance merging capture of multiple targets. This work provides physical insights into distributed active swarms and could offer a multilevel, decentralized strategy toward controlling swarm robotics in wide applications such as bio-medical devices, machine immunity, and target clearance.

关键词： swarm intelligence robotics multi-tasks artificial intelligence bionics

Fabrication and Characterization of Well-Aligned Zn1-xMnxO Nanorods

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Chinese Physics Letters 2006年第3期23卷 716-719页

作者：常永勤张洪洲龙毅叶荣昌 School of Materials science and engineering University of Science and Technology Beijing Beijing 100083 department of electronics and Material engineering Research School of Physical Science and Engineering Australian National University Australia

Well-Migned Zn1-xMnxO nanorods have been synthesized successfully on bare silicon substrates by a simple evaporation method without using any catalyst. X-ray diffraction and electron microscopy studies demonstrate that the as-grown nanorods are of single wurtzite phase with a preferential growth direction along their c- axes, Quantitative energy-dispersive spectrum analysis reveals that the concentration of manganese is around 4 at,%, Magnetic measurements show the single-phase Zn1-xMnxO nanorod arrays exhibiting the paramagnetic behaviour. Photolumlnescence spectra demonstrate that the Zn1-xMnxO nanorods preserve ultraviolet emission at room temperature.

关键词： DILUTED MAGNETIC SEMICONDUCTORS DOPED ZNO FILMS THIN-FILMS ROOM-TEMPERATURE QUANTUM WIRES ZINC OXIDE FERROMAGNETISM SPECTRA AMBIENT GROWTH