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Optical microcavity： from fundamental physics to functional photonics devices

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Science Bulletin 2016年第3期61卷 185-186页

作者： Yun-feng Xiao Qihuang gong State Key Laboratory for Mesoscopic Physics and School ofPhysics Peking University Beijing 100871 China Collaborative Innovation Center of Quantum Matter Beijing 100871 China

Optical microcavities have attracted strong research interests,for their unique property of confining photons for a long time in small volumes,which significantly enhances light–matter interaction[1].In recent decades,various fabrication techniques of microcavities with higher quality factors(Q)and smaller mode volumes(V_m)have been developed,pushing forward studies from fundamental physics to functional photonics *** optomechanics provides an ideal platform for exploring the quantum nature of macroscopic objects[2]。

关键词：光学微腔光子器件物理功能量子信息处理时间性能相互作用制造技术质量因素

Rational tuning of thorium-organic frameworks by reticular chemistry for boosting radionuclide sequestration

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Nano Research 2022年第2期15卷 1472-1478页

作者： Han feng Xiaohong Xiong Lele gong Huiping Zhang Ying Xu Xuefeng feng feng Luo School of Chemistry Biology and Materials ScienceEast China University of TechnologyNanchang 330013China

The reticular chemistry strategy presents a powerful molecule-design tool to tailor the physical and chemical properties of metal-organic framework(MOF).In this work,we for the first time investigated the effect of organic ligands on the radionuclide sequestration(TcO_(4)^(-))of thorium-organic *** a coordination modulation technique,two novel isoreticular thorium-organic frameworks,namely Th-MOF-67 and Th-MOF-68,were *** to the antetype MOF of Th-MOF-66 that shows extremely low uptake of ReO_(4)^(-)(a chemical surrogate of radioactive TcO_(4)^(-)),the isoreticular MOFs of Th-MOF-67 and Th-MOF-68 enable ultrahigh uptake of ReO_(4)^(-),giving an impressively 36.8-fold or 56-fold enhancement,*** adsorption capacity of Th-MOF-68 is as high as 560 mg/g,exceeding most reported adsorbents for such *** mechanism for such exceptional outstanding performance,as unveiled by both the single crystal X-ray diffraction and theoretical calculation,is due to coordination interaction for Th-MOF-67,when a tetrazolate ligand was used,or a combined effect from both coordination interaction and anion-exchange for Th-MOF-68,if using a triazolate ligand.

关键词： thorium-organic framework ligand effect defect site anion exchange radionuclide sequestration

MoM-PO/SBR Algorithm Based on Collaborative Platform and Mixed Model

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Transactions of Nanjing University of Aeronautics and Astronautics 2019年第4期36卷 589-598页

作者： TANG Xiaobin feng Yuan gong Xiaoyan China Academy of Electronics and Information Technology Beijing 100041P.R.China Department of Radar Technology Academy of Air Force Early WarningWuhan 430019P.R.China Department of Command Rocket Army Command AcademyWuhan 430012P.R.China

For electromagnetic scattering of 3?D complex electrically large conducting targets,a new hybrid algorithm,MoM?PO/SBR algorithm,is presented to realize the interaction of information between method of moment(MoM)and physical optics(PO)/shooting and bouncing ray(SBR).In the algorithm,the COC file that based on the Huygens equivalent principle is introduced,and the conversion interface between the equivalent surface and the target is *** then,the multi?task flow model presented in this paper is adopted to conduct CPU/graphics processing unit(GPU)tests of the algorithm under three modes,i.e.,MPI/OpenMP,MPI/compute unified device architecture(CUDA)and multi?task programming model(MTPM).Numerical results are presented and compared with reference solutions in order to illustrate the accuracy and the efficiency of the proposed algorithm.

关键词： graphics processing unit(GPU) multi⁃task programming model(MTPM) physical optics(PO) method of moment(MoM)

Statistically robust design of linear filter for non-regenerative MIMO relay systems

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The Journal of China Universities of Posts and Telecommunications 2011年第3期18卷 34-40页

作者： WANG Ying LI Gen gong feng Wireless Technology Innovation Institute Beijing University of Posts and Telecommunications Beijing 100876 China Key Laboratory of Universal Wireless Communications Ministry of Education Beijing University of Posts and Telecommunications Beijing 100876 China

This paper addresses the robust linear filter design issues for non-regenerative multiple input multiple output （MIMO） relay systems with imperfect channel state information （CSI） in both or partial hops. By considering statistical Kronecker channel model involving channel mean and antenna correlation, the robust linear processing schemes in imperfect CSI scenario for both hops are first derived based on mean squared error （MSE） criterion. In addition to this, the result is also extended to two practical scenarios, i.e. imperfect CSI for relay link with perfect CSI for access link and imperfect CSI for access link with perfect CSI for relay link. Simulation results show that the proposed scheme is capable of mitigating the performance degradation caused by the imperfect CSI.

关键词： MIMO relay linear filter robust design

考虑社会学习的产品定价和质量决策——参照效应与消费者异质性的影响

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管理工程学报 2025年第1期39卷 196-213页

作者：李锋魏莹华南理工大学工商管理学院暨南大学管理学院广州品牌创新发展研究基地

消费者通过观察电商平台的产品评论信息更新对产品质量的感知,这种社会学习行为直接影响消费者的购买决策以及企业的产品质量和价格策略。本文考虑消费者购买过程中的两种参照效应:学习参照和体验参照。前者指购买前消费者关于产品质量... 详细信息

消费者通过观察电商平台的产品评论信息更新对产品质量的感知,这种社会学习行为直接影响消费者的购买决策以及企业的产品质量和价格策略。本文考虑消费者购买过程中的两种参照效应:学习参照和体验参照。前者指购买前消费者关于产品质量的预判对社会学习的效果产生参照效应;后者指学习更新后的质量感知对于消费者购买后的质量体验形成参照。本文构建多智能体模型,以产品评论信息为载体,研究消费者社会学习中的参照效应以及消费者异质性对企业产品质量和价格决策的影响,之后进一步讨论了平台信息策略和企业区别定价策略的效果。研究发现:首先,社会学习中的学习参照效应导致企业降低价格、提高质量且从中受损;而体验参照效应提高用户评价信息均值和集中度,从而使企业提高定价且从中受益。总体而言,社会学习行为有利于企业但参照效应对企业不利。其次,消费者对于产品质量感知的差异程度影响社会学习和参照效应的效果。当质量感知差异程度较低时,考虑参照效应的社会学习行为对企业的价格和质量决策的影响不明显;当感知差异增大到一定程度时,会显著降低企业的价格并影响质量决策。再次,企业从消费者质量先验感知差异程度中受益,但受损于质量后验体验的差异程度。和统一价格策略相比,区别定价能够提高企业收益,但对质量决策影响甚微。最后,平台与卖方共享消费者信息可以减少企业的机会损失,而与买方共享分类统计信息对企业决策影响不大。研究结果同时提供了丰富的管理启示。

关键词：社会学习参照效应质量区别定价智能体建模与仿真

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Solar sail time-optimal interplanetary transfer trajectory design

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Research in Astronomy and Astrophysics 2011年第8期11卷 981-996页

作者： Sheng-Ping gong Yun-feng Gao Jun-feng Li School of Aerospace Tsinghua University Beijing 100084 China

The fuel consumption associated with some interplanetary transfer trajectories using chemical propulsion is not affordable. A solar sail is a method of propulsion that does not consume fuel. Transfer time is one of the most pressing problems of solar sail transfer trajectory design. This paper investigates the time-optimal interplanetary transfer trajectories to a circular orbit of given inclination and radius. The optimal control law is derived from the principle of maximization. An indirect method is used to solve the optimal control problem by selecting values for the initial adjoint vari- ables, which are normalized within a unit sphere. The conditions for the existence of the time-optimal transfer are dependent on the lightness number of the sail and the inclination and radius of the target orbit. A numerical method is used to obtain the boundary values for the time-optimal transfer trajectories. For the cases where no time-optimal transfer trajectories exist, first-order necessary conditions of the optimal control are proposed to obtain feasible solutions. The results show that the transfer time decreases as the minimum distance from the Sun decreases during the transfer duration. For a solar sail with a small lightness number, the transfer time may be evaluated analytically for a three-phase transfer trajectory. The analytical results are compared with previous results and the associated numerical results. The transfer time of the numerical result here is smaller than the transfer time from previous results and is larger than the analytical result.

关键词： techniques: miscellaneous -- solar sail -- solar polar orbit

Arbuscular mycorrhizal fungi alter the response of growth and nutrient uptake of snap bean(Phaseolus vulgaris L.) to O_3

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Journal of Environmental Sciences 2011年第6期23卷 968-974页

作者： Shuguang Wang Zhaozhong feng Xiaoke Wang Wenliang gong Department of Environmental Science and Engineering Beijing University of Chemical Technology Beijing 100029 China State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China Beijing Urban Ecosystem Research Station Beijing 100085 China

The effects of arbuscular mycorrhizal fungi（AMF） Glomus mosseae on the responses to elevated O3 in growth and nutrition of snap bean（Phaseolus vulgaris *** Guangzhouyuan） were *** was conducted in growth chambers by using three O3 concentrations（20（CF）,80（CFO1） and 120 nL/L（CFO2）;8 hr/day for 75 days）.Results showed that elevated O3 slightly impacted overall mycorrhizal colonization,but significantly decreased the proportional frequency of hypha and increased the proportional frequency of spores and vesicles,suggesting that O3 had significant effects on mycorrhizal *** O3 significantly decreased yield,dry mass and nutrient contents（N,P,K,Ca and Mg） in both non-mycorrhizal and mycorrhizal ***,significant interactive effects were found in most variables due to that the reduction by O3 in the mycorrhizal plants was less than that in the non-mycorrhizal ***,AMF increased the concentrations of N,P,Ca,and Mg in shoot and *** can be concluded that AMF alleviated detrimental effects of increasing O3 on host plant through improving plant nutrition and growth.

关键词： arbuscular mycorrhizal fungi nutrition status mycorrhizal colonization elevated 03 snap bean

SECOND-ORDER DRIFT FORCES AND MOMENTS BETWEEN TWO SUBMERGED BODIES IN WAVES ON 3D METHOD

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Journal of Hydrodynamics 2005年第1期17卷 117-124页

作者： WANGJian-fang LIJi-de HAOJin-feng CAIXin-gong SchoolofShipbuildingEngineering HarbinEngineeringUniversityHarbin150001China ChinaShipDesignandResearchCenterCo. LtdBeijing100085China MarineDesignandResearchInstituteofChina Shanghai200011China

Two near field methods, namely the integral method and differential method, were presented for giving second order mean drift forces and moments between two fixed submerged bodies in regular waves. For the integral method, with a series of mathematical manipulations, second order drift forces and moments could be easily expressed by distributed sources which could be calculated by source distribution techniques with the assumption that the amplitude of ship motions are small on the basis of the linear 3D frequency theory. For the differential method, drift forces and moments could be expressed by the derivative of velocity potential with respect to space coordinate. Because two bodies would behave as a single body while the clearance is very large, the numerical results of one sphere in such case were given and compared with analytical results of a single sphere which does not involve the effect of free surface. When submerged depth becomes enough large, a good agreement can be reached. Then the integral method was used to predict the second order drift forces and moments of two submerged spheres and spheroids with a small lateral separation distance in waves compared with the numerical results obtained by the differential method and they agree well. By comparison, it indicates the interaction effects between two submerged bodies have a profound influence on the drift forces and moments. In this paper, the forward speed effect on submerged spheres was also considered.

关键词： near-field method integral method differential method mean drift forces and moments two submerged bodies 3D source distribution technique

Buckling response of offshore pipelines under combined tension, bending, and external pressure

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第8期12卷 627-636页

作者： Shun-feng gong Lin YUAN Wei-liang JIN Institute of Structural Engineering Zhejiang University Hangzhou 310058 China

The buckle and collapse of offshore pipeline subjected to combined actions of tension, bending, and external pressure during deepwater installation has drawn a great deal of attention. Extended from the model initially proposed by Kyriakides and his co-workers, a 2D theoretical model which can successfully account for the case of simultaneous tension, bending, and external pressure is further developed. To confirm the accuracy of this theoretical method, numerical simulations are conducted using a 3D finite element model within the framework of ABAQUS. Excellent agreement between the results validates the effectiveness of this theoretical method. The model is then used to study the effects of several important factors such as load path, material prop-erties, and diameter-to-thickness ratio, etc., on buckling behaviors of the pipes. Based upon parametric studies, a few significant conclusions are drawn, which aims to provide the design guidelines for deepwater pipeline with solid theoretical basis.

关键词： Deepwater Offshore pipeline Buckle External pressure