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基于粒子群算法的量子测量系统最优参数求解

现代防御技术 2023年第6期51卷 155-161页

作者：杜石桥李贵兰寇军郝赫吴同秦国卿高红卫北京无线电测量研究所北京100854

基于里德堡原子的量子测量系统相对传统测量方法具有颠覆性优势,是量子探测领域重要发展方向。然而量子测量系统要对多个实验参数进行优化以提升性能,在理论和实验上采用全空间参数扫描的直接优化方式通常比较困难。通过建立量子测量系... 详细信息

基于里德堡原子的量子测量系统相对传统测量方法具有颠覆性优势,是量子探测领域重要发展方向。然而量子测量系统要对多个实验参数进行优化以提升性能,在理论和实验上采用全空间参数扫描的直接优化方式通常比较困难。通过建立量子测量系统信号强度理论模型,并将粒子群算法应用到模型参数优化中,可快速求解测量系统全局最优参数,计算复杂度相比于传统方法降低1个数量级以上。粒子群算法原则上能应用到其他任何量子测量系统中,指导系统快速提升性能,推进实用化进程。

关键词：粒子群算法量子测量系统里德堡原子实验参数全局搜索

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基于里德堡原子的无线电波测量

激光与光电子学进展 2023年第11期60卷 120-126页

作者：郝赫寇军洪玄淼杜石桥黄媛媛秦国卿马骏超史展吴同张梦高红卫李贵兰北京无线电测量研究所北京100039

里德堡原子无线电波传感器的出现正在推动现代传感和测量方式的转变,利用量子效应实现经典无线电波测量无法比拟的全新探测能力。本文回顾了基于里德堡原子的无线电波测量进展,梳理了领域发展脉络,详细介绍了无线电波测量灵敏度极限并... 详细信息

里德堡原子无线电波传感器的出现正在推动现代传感和测量方式的转变,利用量子效应实现经典无线电波测量无法比拟的全新探测能力。本文回顾了基于里德堡原子的无线电波测量进展,梳理了领域发展脉络,详细介绍了无线电波测量灵敏度极限并展望了未来的发展趋势。该研究将助力领域的发展以及工程应用的推进。

关键词：原子里德堡无线电波灵敏度

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A note on the lake level variations of Nam Co,south-central Tibetan Plateau from 2005 to 2019

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Research in Cold and Arid Regions 2020年第6期12卷 430-435页

作者： shiqiao Zhou Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China

Tibetan lake levels are sensitive to global change,and their variations have a large impact on the environment,local agriculture and animal husbandry *** many remote sensing data of Tibetan lake level changes have been reported,few are from in-situ *** note presents the first in-situ lake level time series of the central Tibetan *** 2005,daily lake level observations have been performed at Lake Nam Co,one of the largest on the Tibetan *** interannual lake level variations show an overall increasing trend from 2006 to 2014,a rapid decrease from 2014 to 2017,and a surge from 2017 to *** annual average lake level of the hydrological year(May−April)rose 66 cm from 2006 to 2014,dropped 59 cm from 2014 to 2017,and increased 20 cm from 2017 to 2018,resulting in a net rise of 27 cm or an average rate of about 2 cm per *** to the annual average lake level based on the calendar year,it is better to use the annual average lake level based on the hydrological year to determine the interannual lake level *** the lake level was stable in May,it is appropriate to compare May lake levels when examining interannual lake level changes with fewer ***,remote sensing results agree well with the in-situ lake level observations;however,some significant deviations *** the comparable 2006−2009 period,the calendar-year average lake level observed insitu rose by 10−11 cm per year,which is lower than the ICESat result of 18 cm per year.

关键词： Lake Nam Co lake level change in-situ measurement Tibetan Plateau

Modeling and Analysis of a Random Excited Double-Clamped Piezoelectric Energy Harvester

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Journal of Beijing Institute of Technology 2017年第3期26卷 297-303页

作者： Xiaoya Zhou shiqiao Gao Haipeng Liu State Key Laboratory of Explosion Science and Technology Beijing Institute of TechnologyBeijing 100082China

A double-clamped piezoelectric energy harvester subjected to random excitation is presented,for which corresponding analytical model is established to predict its output *** the presented theoretical natural frequency and equivalent stiffness of vibrator,the closed-form expressions of mean power and voltage acquired from the double-clamped piezoelectric energy harvester under random excitation are *** theoretical analysis is conducted for the output performance of the doubleclamped energy harvester with the change of spectrum density（SD）of acceleration,load resistance,piezoelectric coefficient and natural frequency value,which is found to closely agree with Monte Carlo simulation and experimental results.

关键词： double-clamped energy harvester random excitation output characteristics

The effect of the beam shapes on the doubly-clamped piezoelectric energy harvester

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Applied Mathematics and Mechanics(English Edition) 2019年第9期40卷 1361-1374页

作者： Lei JIN shiqiao GAO Xiyang ZHANG School of Mechatronic Engineering Beijing Institute of Technology

For a piezoelectric energy harvester composed of a doubly-clamped beam with arbitrary width shapes and a proof mass, the influence of beam shapes and electrode arrangements on different electric outputs is analyzed. The output performances of piezoelectric energy harvesters with rectangular shape, concave trapezoidal shape, and concave parabolic shape are compared, and an optimization way is given. The experimental results validate the effectiveness of the methods.

关键词： doubly-clamped width shape piezoelectric energy harvester electrode connection

Response of Zhadang Glacier runoffin Nam Co Basin,Tibet,to changes in air temperature and precipitation form

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Chinese Science Bulletin 2010年第20期55卷 2103-2110页

作者： ZHOU shiqiao KANG ShiChang GAO TanGuang ZHANG GuoShuai Key Laboratory of Tibetan Environment Changes and Land Surface Processes Institute of Tibetan Plateau Research Chinese Academy of Sciences Beijing 100085 China State Key Laboratory of Cryospheric Sciences Chinese Academy of Sciences Lanzhou 730000 China

This paper describes 2007/2008 inter-annual changes in runoff from the Zhadang Glacier located on the northern slope of Nyainqêntanglha Range,Tibet,and analyzes their *** increased by 17.9%in summer months of 2008 compared with the same period in 2007,drainage basin runoff decreased by 33.3%,and glacial meltwater decreased by 53.8%.Change in positive accumulated air temperature explained approximately half of the inter-annual difference in glacial meltwater using a degree-day *** suggests that the glacier is extremely sensitive to changes in air *** balance analysis showed that change in glacier surface albedo,considered to be caused by difference in precipitation form,resulted in the large inter-annual difference in glacial *** was shown statistically that precipitation form in the summer months of 2007 was mainly rainfall which comprised 71.5%of total precipitation,while during the same period in 2008 rainfall accounted for 30.7%,with the majority of precipitation falling as *** form should be considered an independent factor when analyzing glacier sensitivity to climate change or forecasting the runoff from certain glaciers.

关键词：降水形态冰川变化年径流量气温变化西藏纳木错盆地冰川融水

Rapid synthesis of highly active Pt/C catalysts with various metal loadings from single batch platinum colloid

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Journal of Energy Chemistry 2020年第8期29卷 138-145,I0005页

作者： Yuxin Li Xiang Zhu Yawen Chen shiqiao Zhang Jia Li Jianguo Liu Jiangsu Key Laboratory for Nano Technology National Laboratory of Solid State MicrostructuresCollege of Engineering and Applied Sciencesand Collaborative Innovation Center of Advanced MicrostructuresNanjing UniversityNanjing 210093JiangsuChina Kunshan Innovation Institute of Nanjing University Kunshan Sunlaite New Energy Co.Ltd.Suzhou 215347JiangsuChina

A series of Pt/C catalysts for proton exchange membrane fuel cells(PEMFCs) with various metal loadings is synthesized by a microwave-assisted polyol process via mixing an extremely stable platinum colloid(> 3 months’ shelf life) from single batch preparation with activated carbon ethylene glycol suspension.21 wt%, 42 wt% and 61 wt% Pt loadings are employed to showcase the advantages of the improved polyol process. The ultraviolet(UV)–visible spectra and ζ-potential measurements are conducted to monitor the wet chemistry process during catalyst preparation. The powder X-ray diffraction(XRD), transmission electron microscopy(TEM) and thermogravimetric analysis(TGA) characterizations are carried out on catalysts. The catalyst activities are investigated using electrochemical and single cell tests. The stability of Pt nanoparticle colloid is explored by ORR, cyclic voltammetry(CV) and ζ-potential measurements. The TEM results show the Pt particle sizes of the colloid, and the sizes of the 21 wt%, 42 wt% and 61 wt%Pt/C samples are 2.1–3.9 nm. Because of the high Pt dispersion, the Pt/C catalysts exhibit superior electroactivity toward ORR. In addition, four 61 wt% Pt/C catalysts made from the Pt colloid with 0–3 months’ shelf life show almost the same performance, which exhibits superior stability of the Pt colloid system without surfactant protection.

关键词： PEMFC Pt/C catalyst Microwave irradiation Modified polyol process Platinum nanocolloid Oxygen reduction reaction

Simulation research of a counter‑fow rotary kiln hazardous waste incineration system

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International Journal of Coal Science & Technology 2022年第4期9卷 49-58页

作者： shiqiao Yang Qingfeng Kong Dewang Zeng Shiliang Wu Feng Gong Rui Xiao Key Laboratory of Energy Thermal Conversion and Control of Ministry of Education School of Energy and EnvironmentSoutheast UniversityNanjing 210096China Everbright Environmental Protection Technology Equipment(Changzhou)Co. Ltd.Changzhou 213011China

As industrialization accelerates and the amount of hazardous waste generated gradually increases,the means of disposal of hazardous waste is of increasing *** this paper,a 40 t/d counter-fow rotary kiln incineration system owned by a Jiangsu environmental protection company was *** software Aspen Plus was used to build the mixed pyrolysis model and the software Fluent was used to build the computational fuid dynamics model of the incineration *** infuence of the calorifc value of the hazardous waste,the operating temperature and the air supply on the operational efectiveness of the incineration system were analyzed by varying the simulation *** results show that the SO_(x)and NO_(x)content of the product is lower when the operating temperature is above 800℃.The incineration system could only operate above 800℃when the calorifc value of the hazardous waste is not less than 1500 kcal/*** incineration system operated best at a primary air velocity of 1.5 m/*** simulation results in this paper serve as a guide for the operation of counter-fow rotary kiln incineration systems.

关键词： Hazardous waste Count-fow rotary kiln Aspen plus Fluent Simulation

Optimization of Out-of-Plane Vibration Energy Harvesters Employing Electret

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Journal of Beijing Institute of Technology 2017年第3期26卷 304-310页

作者： Chunhui Gao shiqiao Gao Haipeng Liu Lei Jin Junhu Lu School of Mechatronical Engineering Beijing Institute of TechnologyBeijing 100081China

This paper investigated the dependence of out-of-plane electret-based vibration energy harvesters’output power,frequency bandwidth,and resonance frequency on surface charge density and load *** the external acceleration amplitude and electret size were held constant,the following results are predicted by the numerical investigation：（1）An optimum value exists in the surface charge density to maximize the output *** the surface charge density is increasing,electrostatic forces are enhanced,which emphasizes that the soft spring effect widens the frequency bandwidth and lowers the resonance frequency.（2）Different surface charge densities correspond to different optimum initial air gaps,resonance frequency,and optimum load resistance.（3）With the attenuation of the surface potential,the output power,frequency drift,and frequency bandwidth decreased.（4）An optimum value exists in the load resistance to maximize the output *** the load resistance is decreasing,electrostatic force is enhanced,which lowers the resonance frequency.（5）A maximum frequency bandwidth exists with further load resistance increasing,and the initial air gap is smaller,the greater the frequency bandwidth.

关键词： electret optimum surface charge density load resistance