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Quafu-Qcover:Explore combinatorial optimization problems on cloud-based quantum computers

Chinese Physics B 2024年第5期33卷 104-115页

作者：许宏泽庄伟峰王正安黄凯旋时运豪马卫国李天铭陈驰通许凯冯玉龙刘培陈墨李尚书杨智鹏钱辰靳羽欣马运恒肖骁钱鹏顾炎武柴绪丹普亚南张翼鹏魏世杰增进峰李行龙桂鲁金贻荣于海峰范桁刘东胡孟军 Beijing Academy of Quantum Information Sciences Beijing 100193China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Institute of Physics Chinese Academy of SciencesBeijing 100190China Frontier Science Center for Quantum Information Beijing 100184China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation UCASBeijing 100190China

We introduce Quafu-Qcover,an open-source cloud-based software package developed for solving combinatorial optimization problems using quantum simulators and hardware ***-Qcover provides a standardized and comprehensive workflow that utilizes the quantum approximate optimization algorithm(QAOA).It facilitates the automatic conversion of the original problem into a quadratic unconstrained binary optimization(QUBO)model and its corresponding Ising model,which can be subsequently transformed into a weight *** core of Qcover relies on a graph decomposition-based classical algorithm,which efficiently derives the optimal parameters for the shallow QAOA ***-Qcover incorporates a dedicated compiler capable of translating QAOA circuits into physical quantum circuits that can be executed on Quafu cloud quantum *** to a general-purpose compiler,our compiler demonstrates the ability to generate shorter circuit depths,while also exhibiting superior speed ***,the Qcover compiler has the capability to dynamically create a library of qubits coupling substructures in real-time,utilizing the most recent calibration data from the superconducting quantum *** ensures that computational tasks can be assigned to connected physical qubits with the highest *** Quafu-Qcover allows us to retrieve quantum computing sampling results using a task ID at any time,enabling asynchronous ***,it incorporates modules for results preprocessing and visualization,facilitating an intuitive display of solutions for combinatorial optimization *** hope that Quafu-Qcover can serve as an instructive illustration for how to explore application problems on the Quafu cloud quantum computers.

关键词： quantum cloud platform combinatorial optimization problems quantum software

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Quafu-RL:The cloud quantum computers based quantum reinforcement learning

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Chinese Physics B 2024年第5期33卷 29-34页

作者：靳羽欣许宏泽王正安庄伟峰黄凯旋时运豪马卫国李天铭陈驰通许凯冯玉龙刘培陈墨李尚书杨智鹏钱辰马运恒肖骁钱鹏顾炎武柴绪丹普亚南张翼鹏魏世杰曾进峰李行龙桂鲁金贻荣于海峰范桁刘东胡孟军 Beijing Academy of Quantum Information Sciences Beijing 100193China State Key Laboratory of Low Dimensional Quantum Physics Department of PhysicsTsinghua UniversityBeijing 100084China Institute of Physics Chinese Academy of SciencesBeijing 100190China Frontier Science Center for Quantum Information Beijing 100184China School of Physical Sciences University of Chinese Academy of SciencesBeijing 100190China CAS Center for Excellence in Topological Quantum Computation University of Chinese Academy of SciencesBeijing 100190China School of Mathematical Sciences Nankai UniversityTianjin 300071China

With the rapid advancement of quantum computing,hybrid quantum–classical machine learning has shown numerous potential applications at the current stage,with expectations of being achievable in the noisy intermediate-scale quantum(NISQ)*** reinforcement learning,as an indispensable study,has recently demonstrated its ability to solve standard benchmark environments with formally provable theoretical advantages over classical ***,despite the progress of quantum processors and the emergence of quantum computing clouds,implementing quantum reinforcement learning algorithms utilizing parameterized quantum circuits(PQCs)on NISQ devices remains *** this work,we take the first step towards executing benchmark quantum reinforcement problems on real devices equipped with at most 136 qubits on the BAQIS Quafu quantum computing *** experimental results demonstrate that the policy agents can successfully accomplish objectives under modified conditions in both the training and inference ***,we design hardware-efficient PQC architectures in the quantum model using a multi-objective evolutionary algorithm and develop a learning algorithm that is adaptable to quantum *** hope that the Quafu-RL can be a guiding example to show how to realize machine learning tasks by taking advantage of quantum computers on the quantum cloud platform.

关键词： quantum cloud platform quantum reinforcement learning evolutionary quantum architecture search

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Global change and biological invasions

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Journal of Plant Ecology 2022年第3期15卷 425-428页

作者： yu-long feng Daolin Du Mark van Kleunen Liaoning Key Laboratory for Biological Invasions and Global Changes College of Bioscience and BiotechnologyShenyang Agricultural UniversityShenyang 110866China School of the Environment and Safety Engineering Jiangsu UniversityZhenjiang 212013China Department of Biology University of KonstanzKonstanzGermany Zhejiang Provincial Key Laboratory of Plant Evolutionary Ecology and Conservation Taizhou UniversityTaizhou 318000China

Invasion by exotic species is one of the serious socio-economic,environmental and ecological problems currently faced by *** invasions have changed the species composition,structure and function of ecosystems,and are seriously threatening global biodiversity,economy and human health(Iqbal et al.2021;Wang et al.2020;Yang et al.2021;Zhao et al.2020;Zheng et al.2015).Biological invasions have resulted in an economic loss of at least US$1.288 trillion over the past few decades worldwide(Diagne et al.2021).As a consequence of these far-reaching impacts,biological invasions have become a hot research topic in modern ecology,and attract major attention from international organizations,governments and scientists all over the world.

关键词： invasion consequence

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Soil microbes alleviate allelopathy of invasive plants

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Science Bulletin 2015年第12期60卷 1083-1091,I0002页

作者： Yang-Ping Li yu-long feng Ya-Jun Chen Yao-Hua Tian Key Laboratory of Tropical Forest Ecology XishuangbannaTropical Botanical Garden Chinese Academy of SciencesKunming 650032 China University of Chinese Academy of Sciences Beijing 100039China College of Bioscience and Biotechnology ShenyangAgricultural University Shenyang 110866 China yunnan Tropical Crops Science Research Institute Jinghong 666100 China

Soil microbes are one of the most important determinants of allelopathic effects in the field. However, most studies testing the role of allelopathy in biological invasions did not consider the roles of soil microbes. Here we tested the hypothesis that soil microbes which can degrade allelochemicals may accumulate in soils over time by adaptation and therefore increase the degradation of allelochemicals and alleviate the allelopathic effects in biological invasions. As expected, soil microbes signifi- cantly decreased the allelopathic effects of leaf leachates of eight in the nine invasive plant species studied. In addition, Ageratina adenophora showed lower allelopathic effects in soil with long or intermediately invasion history than those in soil with short invasion history. The two main allelo- chemicals of the invader were degraded more rapidly with increasing invasion history in the soil. Correspondingly,biomass and activity of the soil microbes were higher in the soils with long invasion history than in that with short invasion history. Our results indicate that soil microbes may graduaUy adapt to the allelochemicals of Ageratina and alleviate its allelopathic effects and thus support the above hypothesis. It is necessary to consider the effects of soil microbes when testing the roles of allelopathy or the novel weapons hypothesis in biological invasions.

关键词： Adaptation Allelopathy Degradationof allelochemicals Soil microbes Invasive plants

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Changes in vegetation and soil properties following 6 years of enclosure in riparian corridors

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Journal of Plant Ecology 2020年第2期13卷 131-138页

作者： Di Wang Yi-Ran Zhang yu-long feng Zhi Liu Bo Qu College of Plant protection Shenyang Agricultural UniversityShenyang 110016Liaoning ProvinceChina Liaoning Key Laboratory for Biological Invasions and Global Changes Shenyang Agricultural UniversityShenyang 110016Liaoning ProvinceChina Liaoning Provincial Key Laboratory for Urban Ecology Shenyang Academy of Environmental SciencesShenyang 110016Liaoning ProvinceChina State Key Laboratory of Urban and Regional Ecology Research Center for Eco-Environmental SciencesChinese Academy of SciencesBeijing 100085China College of Bioscience and Biotechnology Shenyang Agricultural UniversityShenyang 110016Liaoning ProvinceChina

Aims Riparian corridors play vital roles in the maintenance of ***,plant species diversity and vegetation coverage in riparian corridors are seriously threatened by increasing pressure owing to livestock consumption and anthropogenic disturbance;even the stability of river courses has been *** establishment of enclosures is a widely used strategy to restore degraded grassland ecosystems,but its impact on degraded herbaceous riparian vegetation and soil properties remains *** aim of this study was to evaluate whether species composition,richness,diversity,and soil properties can be recovered by the *** Twenty long-term monitoring sample plots were set in the Liaohe main stream river,Liaohe main stream river was enclosed for grazing and farmland exclusion in *** height,coverage and individual numbers of plant were recorded for species richness and diversity evaluation from 2012 to 2017;soil nutrients were measured for comparative analysis in 2012 and *** examined the effects of the establishment of enclosures on plant species diversity and soil properties from 2012 to 2017 in the riparian corridors of the Liaohe River system in *** Findings Plant species richness and diversity significantly increased from 2012 to *** dominance of Asteraceae plants increased,while the abundance of Gramineae plants decreased over *** difference in abundance increased each year since enclosure was implemented in *** concentrations of phosphorus and potassium in the soil significantly decreased as a result of the combined effects of vegetation restoration and prohibition of farming practices following the establishment of *** was also a lag time related to the response of soil organic matter to the establishment of *** conclusion,our study provides new evidence regarding the response of species diversity,species composition and soil properties following riparian vegetation rest

关键词： herbaceous vegetation dominant species composition species diversity Liaohe river riparian corridors soil properties ecological restoration

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Shifts in chemical and microbiological properties belowground of invader Ageratina adenophora along an altitudinal gradient

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Journal of Plant Ecology 2022年第3期15卷 561-570页

作者： Wei-Tao Li yu-long Zheng Rui-Fang Wang Zheng-Ying Wang Yan-Mei Liu Xiong Shi Zhi-Yong Liao Yang-Ping Li yu-long feng CAS Key Laboratory of Tropical Forest Ecology Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMengla 666303China Center of Conservation Biology Core Botanical GardensChinese Academy of SciencesMengla 666303China College of Life Sciences University of Chinese Academy of SciencesBeijing 100049China College of Agriculture and Forestry Puer UniversityPuer 665000China College of Bioscience and Biotechnology Liaoning Key Laboratory for Biological Invasions and Global ChangesShenyang Agricultural UniversityShenyang 110866China

Tropical mountain ecosystems are usually colonized by numerous invasive plant species and represent an ideal‘natural laboratory’to study the effects of altitude on plant *** aim of this study was to investigate the soil chemical and microbiological properties along an altitudinal gradient on a mountain colonized by the invader Ageratina *** soil of *** was collected over an altitudinal gradient(1400–2400 m)in Ailao Shan,*** determined soil organic carbon(C),nutrient contents,enzyme activities,bacterial community composition as well as C and nitrogen(N)contents of the plant *** stoichiometric indices were calculated to estimate the relative C,N or P limitations of the microbial *** was a significant effect of altitude on soil organic C in the rhizosphere,and a turning point in these measured variables was detected at an altitude of 2000 *** low elevations,the rapid growth of invasive plants depleted the deficient phosphorus(P)in tropical soils,leading to microbial P limitation;at high elevations,microbes invested more energy to obtain C from resistant litter,leading to microbial C *** beta diversity and soil pH contributed most to the altitudinal differences in ecoenzymatic stoichiometry,and Proteobacteria and Acidobacteria were the dominant bacterial phyla that determined the nutrient uptake status of *** results demonstrate how microbial nutrient acquisition belowground of *** along an altitudinal gradient,which could contribute to further knowledge about the effects of altitude on biological invasion.

关键词： Ageratina adenophora nutrients ecoenzymatic stoichiometry microbial metabolic limitation bacterial community

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AMF colonization and community of a temperate invader and co-occurring natives grown under different CO_(2) concentrations for 3 years

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Journal of Plant Ecology 2022年第3期15卷 437-449页

作者： Xiu-Rong Lu Wei-Wei feng Wen-Jun Wang Ji-Xin Chen Jian-Kun Sun Bo Qu Ming-Chao Liu yu-long feng Liaoning Key Laboratory for Biological Invasions and Global Changes College of Bioscience and BiotechnologyShenyang Agricultural UniversityShenyangLiaoning 110866China

Global changes such as atmospheric CO_(2)enrichment often facilitate exotic plant invasions and alter soil arbuscular mycorrhizal fungi(AMF)***,it is still unclear whether the effects of CO_(2)enrichment on exotic plant invasions are associated with its effects on root-AMF symbiosis of invasive and native *** address this issue,the annual invasive plant Xanthium strumarium and two phylogenetically related annual natives were compared under ambient and elevated CO_(2)concentrations for three consecutive *** CO_(2)enrichment increased AMF colonization rates for the species only in few cases,and the invader did not benefit more from CO_(2)enrichment in terms of AMF *** ambient CO_(2)concentration,however,the invader had a higher AMF colonization rate than the natives in the first year of the study,which disappeared in the second and third year of the study due to the increase of AMF colonization rates in the natives but not in the *** influences of species,CO_(2)concentrations and planting year on AMF colonization were associated with their effects on both soil nutrient and AMF community,and the former may be more important as it also influenced the *** results indicate that the invader could more quickly form symbiosis with soil AMF,contributing to adaptation and occupation of new habitats,and that it is necessary to consider the roles of AMF and the effects of time when determining the effects of global changes such as atmospheric CO_(2)enrichment on exotic plant invasions.

关键词： AMF community colonization consecutive planting elevated CO_(2) exotic plant invasions soil characteristics

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Microstructure,wear and friction behavior of CoCrAITaY-xCNTs composite coatings deposited by laser-induction hybrid cladding

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Rare Metals 2024年第4期43卷 1815-1827页

作者： Sheng-feng Zhou yu long Yan-Liang Yi Cheng Deng Lian-Xi Hu Institute of Advanced Wear&Corrosion Resistant and Functional Materials Jinan UniversityGuangzhou510632China Wuhan National Laboratory for Optoelectronics(WNLO) Huazhong University of Science and TechnologyWuhan430074China MOE Key Laboratory of New Processing Technology for Non-Ferrous Metals and Materials Guangxi Key Laboratory of Processing for Non-Ferrous Metals and Featured MaterialsGuangxi UniversityNanning530004China School of Mechatronics Engineering Guangdong Polytechnic Normal UniversityGuangzhou510635China School of Materials Science and Engineering Harbin Institute of TechnologyHarbin150001China

To improve the wear performance of CoCrAlYTa coating,part of the carbon nanotubes(CNTs)chemically reacted with Ta to form reinforcement phase(TaC),while the other CNTs were retained as lubrication ***,the CoCrAlYTa-xCNTs(x=0,1,2,and 4;wt%)composite coatings were prepared by laserinduction hybrid cladding(LIHC),and the microstructure and wear resistance of coatings were systematically *** show that the coatings are mainly composed of TaC,y-(Co,Cr)andβ-(Co,Cr)*** the CNTs content increases from 0 wt%to 4 wt%,the volume fraction of TaC increases from 13.11 vol%to 16.12 vol%.Meanwhile,the nano-hardness ofγ-(Co,Cr)andβ-(Co,Cr)Al are improved from 7.49 and 9.72 to 9.36 and 11.19 GPa,*** a result,the microhardness of coating increases from HV536.25 to HV 738.16,the wear rate decreases from32.4×10^(-3)to 6.1×10^(-3)mg·m^(-1),and the average friction coefficient decreases from 0.55 to *** good wear performance of the coating is attributed to the formation of TaC and the existence of remained CNTs lubricant film.

关键词： Carbon nanotube MCrAlY coating Friction and wear performance Laser-induction hybrid cladding

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Frequency Domain Fatigue Evaluation on SCR Girth-Weld Based on Structural Stress

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China Ocean Engineering 2024年第2期38卷 255-270页

作者： ZHANG long ZHAO Tian-feng College of Safety and Ocean Engineering China University of Petroleum(Beijing)Beijing 102249China

The Steel Catenary Riser(SCR)is a vital component for transporting oil and gas from the seabed to the floating *** harsh environmental conditions and complex platform motion make the SCR’s girth-weld prone to fatigue *** structural stress fatigue theory and Master S-N curve method provide accurate predictions for the fatigue damage on the welded joints,which demonstrate significant potential and compatibility in multi-axial and random fatigue ***,we propose a new frequency fatigue model subjected to welded joints of SCR under multiaxial stress,which fully integrates the mesh-insensitive structural stress and frequency domain random process and transforms the conventional welding fatigue technique of SCR into a spectrum analysis technique utilizing structural ***,a full-scale FE model of SCR with welds is established to obtain the modal structural stress of the girth weld and the frequency response function(FRF)of modal coordinate,and a biaxial fatigue evaluation about the girth weld of the SCR can be achieved by taking the effects of multi-load correlation and pipe-soil interaction into *** research results indicate that the frequency-domain fatigue results are aligned with the time-domain results,meeting the fatigue evaluation requirements of the SCR.

关键词： SCR girth weld random vibration self(cross)power spectrum structural stress method biaxial fatigue damage

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Phase separation of GRP7 facilitated by FERONIAmediated phosphorylation inhibits mRNA translation to modulate plant temperature resilience

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Molecular Plant 2024年第3期17卷 460-477页

作者： Fan Xu long Wang Yingbin Li Junfeng Shi Dorothee Staiger feng yu state Key Laboratory of Chemo/Biosensing and Chemometrics College of Biologyand Hunan Key Laboratory of Plant Functional Genomics and Developmental RegulationHunanUniversityChangsha 410082P.R.China State Key Laboratory of Hybrid Rice Hunan Agricultural Biotechnology Research InstituteHunan Academy of Agricultural SciencesChangsha 410125P.R.China RNA Biology and Molecular Physiology Faculty of BiologyBielefeld University33615 BielefeldGermany

Changes in ambient temperature profoundly affect plant growth and ***,the molecu-larbasis of plant acclimation to temperature fluctuation is of great *** this study,we discovered that GLYCINE-RICH RNA-BINDING PROTEIN 7(GRP7)contributes to cold and heat tolerance in Arabidopsis *** found that exposure to a warm temperature rapidly induces GRP7 condensates in planta,which can be reversed by transfer to a lower *** biology and biochemical assays revealed that GRP7 undergoes liquid-liquid phase separation(LLPS)in vivo and in *** of GRP7 in the cyto-plasm contributes to the formation of stress granules that recruit RNA,along with the translation machinery component eukaryotic initiation factor 4E1(elF4E1)and the mRNA chaperones COLD SHOCK PROTEIN 1(CSP1)and CSP3,to inhibit ***,natural variations in GRP7 affecting the residue phos-phorylated by the receptorkinase FERONIA alter its capacity to undergo LLPS and correlate with the adap-tation of some Arabidopsis accessions to a widertemperature *** together,ourfindings illustrate the role of translational control mediated by GRP7 LLPS to confer plants with temperature resilience.

关键词： fluctuating temperature glycine-rich RNA-binding protein phase separation cold shock proteins translation

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