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Scaling symmetry meets topology

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Science Bulletin 2019年第5期64卷 289-290页

作者： pengfei zhang Hui Zhai Institute for Advanced Study Tsinghua University

In 1970,Vitaly Efimov found an interesting phenomenon in a quantum three-body problem,which is now known as the Efimov *** found that when the two-body in teraction potential is short-ranged and is tuned to the vicinity of an s-wave resonance,an inhnite number of three-body bound states emerge and their eigenenergies En form a geometric sequence as En=-|Eo|exp(—2m/So).

关键词： Scaling symmetry meets topology In 1970

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复式大蒜种子方向控制装置设计与试验

中国农机化学报 2024年第3期45卷 8-13页

作者：张鹏飞刘冬梅崔荣江徐亚丹杭州职业技术学院杭州市310018

为提高大蒜播种机对杂交蒜的播种正芽率,提出串联使用大蒜种子重心靠下和大蒜种子芽尖细长特征进行种子方向控制的方法,即在排种器运种阶段设计分段式护种槽,利用大蒜种子重心靠下特征提高种子直立进入定向器的概率,在换向阶段设计弧形... 详细信息

为提高大蒜播种机对杂交蒜的播种正芽率,提出串联使用大蒜种子重心靠下和大蒜种子芽尖细长特征进行种子方向控制的方法,即在排种器运种阶段设计分段式护种槽,利用大蒜种子重心靠下特征提高种子直立进入定向器的概率,在换向阶段设计弧形开口定向器,使大蒜种子芽尖尽可能露出定向器,提高短芽尖大蒜鳞芽的正芽率。以定向速度和种子芽尖长度为试验因素,正芽率为试验指标,进行台架试验,结果表明,蒜瓣芽尖长度对播种机正芽率影响较为明显,正芽率随定向速度的增加而降低。以金乡杂交蒜为试验对象,对定向系统进行田间播种性能试验,试验结果表明:行走速度为0.14~0.19 m/s时,金乡杂交蒜的正芽率达85%,整体满足大蒜播种农艺要求。串联使用大蒜种子两种物理特征从作业原理上可提高大蒜种子定向稳定性,为大蒜播种机械化发展提供参考。

关键词：大蒜播种机复式定向弧形开口定向器分段式护种槽

基于AHP-熵权法和灰色聚类综合评价的办公建筑智能化改造工程项目施工风险评价

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项目管理技术 2024年第3期22卷 19-26页

作者：杨江南张朋飞中南林业科技大学土木工程学院湖南长沙410004 深圳英飞拓仁用信息有限公司广东深圳518110 四川交通职业技术学院建筑工程系四川成都611130

目前,针对办公建筑智能化改造工程项目施工风险尚未建立一套合适的评价指标体系。通过分析工程项目施工风险研究现状,基于办公建筑智能化改造工程项目施工特征,综合考虑技术、质量、进度、管理和环境5个方面的风险因素,构建三个层次23... 详细信息

目前,针对办公建筑智能化改造工程项目施工风险尚未建立一套合适的评价指标体系。通过分析工程项目施工风险研究现状,基于办公建筑智能化改造工程项目施工特征,综合考虑技术、质量、进度、管理和环境5个方面的风险因素,构建三个层次23个指标的施工风险综合评价指标体系。运用层次分析法(AHP)和熵权法相结合的方法确定各指标的综合权重,并利用灰色聚类法构建综合评价模型。将该模型运用于KG办公楼智能化改造工程项目并进行实证分析,评价结果综合得分50.812 5,说明该项目的施工风险等级为“中等”。根据评价结果提出针对性建议,为从事办公建筑智能化改造工程项目的施工单位提供参考。

关键词：办公建筑智能化改造工程层次分析法熵权法灰色聚类

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无人机集群协同控制技术综述

兵器装备工程学报 2024年第4期45卷 1-9页

作者：张鹏飞何印马振华李亚文中北大学航空宇航学院太原030051 中北大学智能武器研究院太原030051

协同控制技术作为多智能体分工合作完成任务的关键核心技术,能解决无人机集群编队、队形重构和避障避碰等问题,是无人机集群正常运作的基础。针对近几年国内外无人机集群协同控制技术的发展历程,概述3种控制结构原理及其优缺点;分析了基... 详细信息

协同控制技术作为多智能体分工合作完成任务的关键核心技术,能解决无人机集群编队、队形重构和避障避碰等问题,是无人机集群正常运作的基础。针对近几年国内外无人机集群协同控制技术的发展历程,概述3种控制结构原理及其优缺点;分析了基于3种控制结构的编队控制方法及其优缺点;从无人机集群协同编队控制技术出发,分析基于编队控制的避障方法;指出了现阶段无人机集群协同控制技术面临的瓶颈问题,并对协同控制技术的未来发展方向进行了展望,为无人机集群编队控制和避障方法研究提供一定的借鉴。

关键词：无人机集群协同控制控制结构编队控制协同避障

基于DIC技术近距离煤层采动裂隙-位移-应变演化规律相似模拟研究

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矿业科学学报 2024年第4期9卷 519-528页

作者：梅福星尚宇琦孔德中张鹏飞张林吴仕雄贵州大学矿业学院贵州贵阳550025

为研究近距离煤层采动条件下覆岩裂隙演化规律,以安顺煤矿9305工作面为研究对象,利用相似模拟试验研究近距离煤层开采过程中位移场与应变场的演化情况。结果表明:①上覆岩层随着工作面距离的不断推进,先形成离层裂隙和纵向裂隙,随后采... 详细信息

为研究近距离煤层采动条件下覆岩裂隙演化规律,以安顺煤矿9305工作面为研究对象,利用相似模拟试验研究近距离煤层开采过程中位移场与应变场的演化情况。结果表明:①上覆岩层随着工作面距离的不断推进,先形成离层裂隙和纵向裂隙,随后采空区中部部分离层逐渐压实;②位移场在工作面推进方向上出现不对称分布,工作面侧覆岩位移量明显小于采空区靠左区域,位移峰值主要集中在采空区中部;③最大主应变集中位置由采空区中部向开切眼侧以及工作面侧进行不对称转移,开切眼侧集中程度明显大于工作面侧,且最大主应变集中位置与瓦斯富集区存在潜在关联。

关键词：近距离煤层覆岩结构裂隙演化位移应变相似模拟

Preparing quantum states by measurement-feedback control with Bayesian optimization

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Frontiers of physics 2023年第6期18卷 291-299页

作者： Yadong Wu Juan Yao pengfei zhang Department of Physics Fudan UniversityShanghai 200438China State Key Laboratory of Surface Physics Key Laboratory of Micro and Nano Photonic Structures(MOE)Fudan UniversityShanghai 200438China Institute for Nanoelectronic Devices and Quantum Computing Fudan UniversityShanghai 200433China Shanghai Qi Zhi Institute AI TowerXuhui DistrictShanghai 200232China Shenzhen Institute for Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China International Quantum Academy Shenzhen 518048China Guangdong Provincial Key Laboratory of Quantum Science and Engineering Southern University of Science and TechnologyShenzhen 518055China Walter Burke Institute for Theoretical Physics&Institute for Quantum Information and Matter California Institute of TechnologyPasadenaCA 91125USA

The preparation of quantum states is crucial for enabling quantum computations and *** this work,we present a general framework for preparing ground states of many-body systems by combining the measurement-feedback control process(MFCP)with machine learning ***,we employ Bayesian optimization(BO)to enhance the efficiency of determining the measurement and feedback operators within the *** an illustration,we study the ground state preparation of the one-dimensional Bose−Hubbard *** BO,we are able to identify optimal parameters that can effectively drive the system towards low-energy states with a high probability across various quantum *** results open up new directions for further exploration and development of advanced control strategies for quantum computations and simulations.

关键词： state preparation feedback control Bayesian optimization

Scenario-oriented hybrid particle swarm optimization algorithm for robust economic dispatch of power system with wind power

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Journal of Systems Engineering and Electronics 2022年第5期33卷 1143-1150页

作者： WANG Bing zhang pengfei HE Yufeng WANG Xiaozhi zhang Xianxia School of Mechatronic Engineering and Automation Shanghai UniversityShanghai 200444China

An economic dispatch problem for power system with wind power is *** discrete scenario to describe uncertain wind powers,a threshold is given to identify bad scenario *** bad-scenario-set robust economic dispatch model is established to minimize the total penalties on bad scenarios.A specialized hybrid particle swarm optimization(PSO)algorithm is developed through hybridizing simulated annealing(SA)*** SA operators are performed according to a scenario-oriented adaptive search rule in a neighborhood which is constructed based on the unit commitment ***,an experiment is *** computational results show that the developed algorithm outperforms the existing algorithms.

关键词： wind power robust economic dispatch scenario simulated annealing(SA) particle swarm optimization(PSO)

Enthalpy-change driven synthesis of high-entropy perovskite nanoparticles

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Nano Research 2022年第6期15卷 4867-4872页

作者： Siyang Nie Liang Wu Lingci Zhao pengfei zhang School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Due to their diverse and tunable composition,distorted lattice and excellent stability,high-entropy ceramics(HECs)hold great promise for catalysis,especially when they present as nanoparticles(NPs).However,current HECs are typically limited to bulky materials with none or fewer defects,because high synthetic temperature(e.g.,1,000–1,200°C)is usually required to highlight the entropic contribution(TΔS)inΔG=ΔH−TΔ*** different with previous strategies,a negative Gibbs free energy for HECs crystallization is obtained by dramatically decreasing the mixing enthalpy(ΔH).Guided by this principle,single-phase highentropy La(Ni_(0.2)Mn_(0.2)Cu_(0.2)Fe_(0.2)Co_(0.2))O_(3−δ)perovskite(HE-LMO)NPs were prepared at a relatively low temperature(≤500°C).Interestingly,abundant oxygen vacancies were directly created within HE-LMO NPs,which exhibited good activity in catalytic ***,the high-entropy structure endows as-made HE-LMO with robust stability even with 5 vol.%water in feeding *** functional theory(DFT)calculations revealed that the defective sites in HE-LMO NPs facilitated the charge transfer from HE-LMO to CO,thus activating the adsorbed CO *** current work may inspire future design and synthesis of HECs NPs.

关键词： enthalpy-change high-entropy ceramics mechanochemical synthesis perovskite CO oxidation

Nitrogen-rich isoindoline-based porous polymer: Promoting knoevenagel reaction at room temperature

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Green Energy & Environment 2020年第4期5卷 484-491页

作者： Shengtai Hou Yunhao Sun Xueguang Jiang pengfei zhang School of Chemistry and Chemical Engineering Shanghai Jiao Tong UniversityShanghai 200240 China Department of Chemistry University of TennesseeTN 37996USA

Nitrogen-rich porous organic polymers(POPs)with basic features have already shown promising performance in various organic *** the harsh conditions,tedious synthetic methods and the requirement of specific monomers impede their further ***,we introduce isoindoline chemistry into POP *** isoindoline formation process between aniline and bromomethylbenzenedcoupling nucleophilic substitution,HBr elimination,and intramolecular cyclization in one pot,is utilized for POPs ***-rich isoindolinebased porous polymers(IPPs)were obtained with specific surface areas up to 408 m^(2) g^(-1).Unexpectedly,mechanochemistry could enable the rapid(3 h)and solid-state synthesis of IPP ***,this nitrogen-rich catalyst presents excellent activity(isolated yield:99%),scalable ability(up to 14 g per run)and recyclability(five runs)towards the Knoevenagel condensation reaction under mild reaction conditions(water as solvent at room temperature).

关键词： Porous organic polymers Porous basic polymers Nitrogen-doped Mechanochemistry