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认知无线Mesh网络中资源节约的最小信道冲突值组播路由算法

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国防科技大学学报 2016年第4期38卷 76-84页

作者：杨艺清陈志刚中南大学信息科学与工程学院湖南长沙410083

认知无线Mesh网络中满足服务质量约束的多目标优化组播路由问题比单目标优化组播问题更加复杂,为了快速求解认知无线Mesh网络中满足服务质量约束的、以最小化资源消耗与最小化信道冲突值为目标的多目标优化组播路由问题,提出一种基于粒... 详细信息

认知无线Mesh网络中满足服务质量约束的多目标优化组播路由问题比单目标优化组播问题更加复杂,为了快速求解认知无线Mesh网络中满足服务质量约束的、以最小化资源消耗与最小化信道冲突值为目标的多目标优化组播路由问题,提出一种基于粒子群优化算法的问题求解框架,包括问题描述、粒子编码与粒子初始化、适应度函数、粒子飞行、粒子变异、粒子消环。粒子由表示节点之间连接关系的带权邻接矩阵表示,重新定义了用于粒子飞行的3种运算规则以及粒子飞行运算和粒子变异运算。仿真结果表明提出的算法能达到预定目标,资源消耗较低且能获得较低的信道冲突值。

关键词：认知无线Mesh网络组播频谱分配粒子群优化

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中国城乡差距对农地违法非农化的影响

资源科学 2019年第12期41卷 2274-2283页

作者：王青陈志刚南京邮电大学社会与人口学院南京210023 南京大学地理与海洋科学学院南京210023

城乡差距对于农村土地利用特别是农地违法非农化有着不可忽视的影响。本文首先从理论层面探讨了城乡差距对农地违法非农化的影响机理;在此基础上通过构建计量模型,并运用1999-2016年中国大陆31个省(市、区)的面板数据,进行了系统的实证... 详细信息

城乡差距对于农村土地利用特别是农地违法非农化有着不可忽视的影响。本文首先从理论层面探讨了城乡差距对农地违法非农化的影响机理;在此基础上通过构建计量模型,并运用1999-2016年中国大陆31个省(市、区)的面板数据,进行了系统的实证检验。结果显示:城乡差距扩大会导致农地违法非农化规模显著增长,尤其是随着财政支农支出占比的下降和城乡居民人均可支配收入差距的扩大,农地违法非农化规模增幅明显。具体地,在省级层面,财政支农支出占比每下降一个百分点,农地违法非农化规模会增加近25 hm2;城乡居民人均可支配收入差距每扩大10%,农地违法非农化规模也会增加约15 hm2;而城乡土地产出效益差的扩大对农地违法非农化的影响则小得多。此外,在不同经济发展地区(或不同经济发展阶段),城乡差距变化对农地违法非农化的影响存在显著差异。最后从有效遏制农地违法非农化的角度,针对性地提出了缩小城乡差距的相关路径和建议。

关键词：城乡差距农地非农化土地违法财政支农支出城乡居民收入土地产出效益中国

Hierarchical Porous TiO2 Fibre Synthesized by Cotton Template and Its Photocatalytic Performance

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Hierarchical Porous TiO2 Fibre Synthesized by Cotton Templat...

Comparative Study on Electromagnetic and Electrome-chanical Transient Model for Grid-connected Photovoltaic Power System

中国材料大会2012

作者： chengbao Liu Feng chen zhigang chen Junchao Qian Jiangsu Key Laboratory for Environment Functional Materials Suzhou University of Science and Technology Department of Chemistry and Bioengineering Suzhou University of Science and Technology

ISBN: (纸本)9783037856079;3037856076

Hierarchical porous TiO2 fibre was successfully synthesized using cotton as template. Microstructures of product were characterized by Field Emission Scanning Electron Microscope （FESEM）, nitrogen absorption-desorption technique and transmission electron microscopy （TEM）. Titanium oxide material was characterized by repetitious networks consisting of the fibres with diameter of ca. 3-8 μm. The results showed that the products were composed 2-5 nm piled pores stacked by polycrystalline TiO2 nanoparticles. The small crystallite diameter （6-10 nm） and the high specific surface area （83.7 m2·g-1） of sample was believed to be resulted from wide-angle X-ray Diffraction （XRD）, high resolution TEM （HRTEM） and the BET method. While the concentration of methylthionine chloride solution was 20 mg/L, catalyst amount 0.1 g/L, the reaction had a higher decoloring rate following irradiation with a UV light source, the decoloring rate can reach over 100% after 250 min.

关键词： Titanium oxide Porous fibre Cotton template Photocatalytic performance

来源： cnki会议评论

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Energy and Power Engineering 2013年第4期5卷 247-252页

作者： Man Zhang Hao Sun zhigang chen Xiaorong Xie Qirong Jiang Guangdong Electric Power Design Institute Guangzhou China State Key Lab. of Power Systems Department of Electrical Engineering Tsinghua University Beijing China

With the development of new energy technology, there are increasing applications of grid-connected photovoltaic power generation system. However, there is little research on development of electromechanical model of large scale photovoltaic power station. The computational speed will be very slow if electromagnetic transient model is used for stability study because of its complexity. Therefore, study on electromechanical transient model of grid-connected photovoltaic power generation system is of great meaning. In this paper, electromagnetic transient model of photovoltaic power generation system is introduced first, and then a general electromechanical transient model is proposed. These two kinds of simulation model are set up in PSCAD. By comparing the simulation results of two models, the correctness and validity of the electromechanical transient model is verified. It provides reference model for efficient simulation and modeling of grid-connected photovoltaic power station in large-scale power systems.

关键词： Photovoltaic Power Electromagnetic Transient Model Electromechanical Transient Model Simulation Comparison

Plasmonic resonant nonlinearity and synthetic optical properties in gold nanorod suspensions

维普期刊数据库评论

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维普期刊数据库

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Photonics Research 2019年第1期7卷 28-35页

作者： HUIZHONG XU PEPITO ALVARO YINXIAO XIANG TREVOR S.KELLY YU-XUAN REN chenSONG ZHANG zhigang chen Department of Physics and Astronomy San Francisco State University TEDA Applied Physics Institute and School of Physics Nankai University

We experimentally demonstrate self-trapping of light, as a result of plasmonic resonant optical nonlinearity,in both aqueous and organic(toluene) suspensions of gold nanorods. The threshold power for soliton formation is greatly reduced in toluene as opposed to aqueous suspensions. It is well known that the optical gradient forces are optimized at off-resonance wavelengths at which suspended particles typically exhibit a strong positive(or negative) polarizability. However, surprisingly, as we tune the wavelength of the optical beam from a continuous-wave(CW) laser, we find that the threshold power is reduced by more than threefold at the plasmonic resonance frequency. By analyzing the optical forces and torque acting on the nanorods, we show theoretically that it is possible to align the nanorods inside a soliton waveguide channel into orthogonal orientations by using merely two different laser wavelengths. We perform a series of experiments to examine the transmission of the soliton-forming beam itself, as well as the polarization transmission spectrum of a low-power probe beam guided along the soliton channel. It is found that the expected synthetic anisotropic properties are too subtle to be clearly observed, in large part due to Brownian motion of the solvent molecules and a limited ordering region where the optical field from the self-trapped beam is strong enough to overcome thermodynamic fluctuations. The ability to achieve tunable nonlinearity and nanorod orientations in colloidal nanosuspensions with low-power CW laser beams may lead to interesting applications in all-optical switching and transparent display technologies.

关键词： experimentally demonstrate greatly reduced suspended particles

Synthetic optical vortex beams from the analogous trajectory change of an artificial satellite

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Photonics Research 2019年第9期7卷 1101-1105页

作者： HAIPING WANG LIQIN TANG JINA MA XIUYAN ZHENG DAOHONG SONG YI HU YIGANG LI zhigang chen MOE Key Laboratory of Weak-Light Nonlinear Photonics TEDA Applied Physics Institute and School of PhysicsNankai UniversityTianjin300457China Collaborative Innovation Center of Extreme Optics Shanxi UniversityTaiyuan030006China Department of Physics and Astronomy San Francisco State UniversitySan FranciscoCalifornia94132USA

We propose a method to generate specially shaped high-order singular beams of pre-designed intensity distributions. Such a method does not a priori assume a phase formula, but rather relies on the 'cake-cutting and assembly' approach to achieve the azimuthal phase gradient for beam shaping, inspired by the orbital motion trajectory change of an artificial satellite. Based on our method, several typical vortex beams with desired intensity patterns are experimentally generated. As an example, we realize optical trapping and transportation of microorganisms with a triangle-shaped vortex beam, demonstrating the applicability of such unconventional vortex beams in optical trapping and manipulation.

关键词： SOV SLM Synthetic optical vortex beams from the analogous trajectory change of an artificial satellite

Clinicopathological study and diagnosis of rhabdoid tumor of kidney combined with metanephric adenoma

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Chinese Medical Journal 2014年第24期127卷 4290-4291页

作者： Zhang zhigang chen Jianning Zhou Jing Liu Yong Feng Zhiying Tang Luying Jin Yi Department of Pathology the Third Affiliated Hospital Sun Yat-sen University Guangzhou Guangdong 510630 China

Rhabdoid tumor of kidney （RTK） is a highly malignant tumor that occurs in infants and children, and approximately 80% of patients are diagnosed in the first two years of life. It was firstly described in 1978, and was defined as an independent disease in 1981. In the reported literatures, there were less in adolescents and extremely rare in adults.

关键词： rhabdoid tumor metanephric adenoma kidney immunohistoehemistry pathology

纳米α-Al_2O_3颗粒弥散强化镍基复合涂层的耐磨性能研究

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润滑与密封 2006年第3期31卷 33-35,38页

作者：陈彩凤陈志刚江苏大学材料科学与工程学院江苏镇江212013

将纳米α-A l2O3颗粒或N i包裹的纳米α-A l2O3复合粉和镍基粉用湿法混合,采用火焰热喷涂工艺制备了复合涂层,用磨粒磨损试验机进行磨损试验,研究了纳米α-A l2O3的体积分数、粒径和是否预先进行包裹处理对涂层喷焊性和耐磨粒磨损性能... 详细信息

将纳米α-A l2O3颗粒或N i包裹的纳米α-A l2O3复合粉和镍基粉用湿法混合,采用火焰热喷涂工艺制备了复合涂层,用磨粒磨损试验机进行磨损试验,研究了纳米α-A l2O3的体积分数、粒径和是否预先进行包裹处理对涂层喷焊性和耐磨粒磨损性能的影响。结果表明,纳米α-A l2O3以包裹形式加入能有效改善弥散相与N i基涂层的相容性,相应涂层的耐磨性优于未包裹处理;当纳米A l2O3的体积分数为2%时,涂层的耐磨性能最好,为N i基涂层的2倍多;在相同的体积分数下,随着涂层中弥散强化相尺寸的减小,涂层的耐磨性提高。

关键词：纳米α-Al2O3 热喷涂复合涂层耐磨性

Free-space realization of tunable pin-like optical vortex beams

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Photonics Research 2021年第7期9卷 1204-1212页

作者： DOMENICO BONGIOVANNI DENGHUI LI MIHALIS GOUTSOULAS HAO WU YI HU DAOHONG SONG ROBERTO MORANDOTTI NIKOLAOS KEFREMIDIS zhigang chen MOE Key Laboratory of Weak-Light Nonlinear Photonics TEDA Applied Physics Institute and School of PhysicsNankai UniversityTianjin 300457China INRS-EMT 1650 Blvd.Lionel-BouletVarennesQuebec J3X 1S2Canada Department of Applied Mathematics University of CreteHeraklionCrete 71409Greece Institute of Fundamental and Frontier Sciences University of Electronic Science and Technology of ChinaChengdu 610054China Institute of Applied and Computational Mathematics FORTHHeraklionCrete 70013Greece Department of Physics&Astronomy San Francisco State UniversitySan FranciscoCalifornia 94132USA

We demonstrate,both analytically and experimentally,free-space pin-like optical vortex beams (POVBs). Such angular-momentum-carrying beams feature tunable peak intensity and undergo robust antidiffracting propagation,realized by judiciously modulating both the amplitude and the phase profile of a standard laser ***,they are generated by superimposing a radially symmetric power-law phase on a helical phase structure,which allows the inclusion of an orbital angular momentum term to the POVBs. During propagation in free space,these POVBs initially exhibit autofocusing dynamics,and subsequently their amplitude patterns morph into a high-order Bessel-like profile characterized by a hollow core and an annular main lobe with a constant or tunable width during propagation. In contrast with numerous previous endeavors on Bessel beams,our work represents the first demonstration of long-distance free-space generation of optical vortex "pins" with their peak intensity evolution controlled by the impressed amplitude structure. Both the Poynting vectors and the optical radiation forces associated with these beams are also numerically analyzed,revealing novel properties that may be useful for a wide range of applications.

关键词： tunable optical Bessel