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Surrogate-assisted differential evolution using manifold learning-based sampling for highdimensional expensive constrained optimization problems

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Chinese Journal of Aeronautics 2024年第7期37卷 252-270页

作者： Teng long Nianhui YE Rong CHEN Renhe shi Baoshou zhang School of Aerospace Engineering Beijing Institute of TechnologyBeijing 100081China Key Laboratory of Dynamics and Control of Flight Vehicle of Ministry of Education Beijing 100081China China Academy of Launch Vehicle Technology Beijing 100076China

To address the challenges of high-dimensional constrained optimization problems with expensive simulation models,a Surrogate-Assisted Differential Evolution using Manifold Learning-based Sampling(SADE-MLS)is *** SADE-MLS,differential evolution operators are executed to generate numerous high-dimensional candidate *** alleviate the curse of dimensionality,a Manifold Learning-based Sampling(MLS)mechanism is developed to explore the high-dimensional design space *** MLS,the intrinsic dimensionality of the candidate points is determined by a maximum likelihood ***,the candidate points are mapped into a low-dimensional space using the dimensionality reduction technique,which can avoid significant information loss during dimensionality ***,Kriging surrogates are constructed in the low-dimensional space to predict the responses of the mapped candidate *** candidate points with high constrained expected improvement values are selected for global ***,the local search process assisted by radial basis function and differential evolution is performed to exploit the design space *** numerical benchmarks are tested to compare SADE-MLS with other ***,SADE-MLS is successfully applied to a solid rocket motor multidisciplinary optimization problem and a re-entry vehicle aerodynamic optimization problem,with the total impulse and lift to drag ratio being increased by 32.7%and 35.5%,*** optimization results demonstrate the practicality and effectiveness of the proposed method in real engineering practices.

关键词： Surrogate-assisted differential evolution Dimensionality reduction Solid rocket motor Re-entry vehicle Expensive constrained optimization

Pressure transient characteristics of non-uniform conductivity fractured wells in viscoelasticity polymer flooding based on oil-water two-phase flow

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Petroleum Science 2024年第1期21卷 343-351页

作者： Yang Wang Jia zhang shi-long Yang Ze-Xuan Xu shi-Qing Cheng National Key Laboratory of Petroleum Resources and Engineering China University of Petroleum(Beijing)Beijing102249China

Polymer flooding in fractured wells has been extensively applied in oilfields to enhance oil *** contrast to water,polymer solution exhibits non-Newtonian and nonlinear behavior such as effects of shear thinning and shear thickening,polymer convection,diffusion,adsorption retention,inaccessible pore volume and reduced effective ***,the flux density and fracture conductivity along the hydraulic fracture are generally non-uniform due to the effects of pressure distribution,formation damage,and proppant *** this paper,we present an oil-water two-phase flow model that captures these complex non-Newtonian and nonlinear behavior,and non-uniform fracture characteristics in fractured polymer *** hydraulic fracture is firstly divided into two parts:high-conductivity fracture near the wellbore and low-conductivity fracture in the far-wellbore section.A hybrid grid system,including perpendicular bisection(PEBI)and Cartesian grid,is applied to discrete the partial differential flow equations,and the local grid refinement method is applied in the near-wellbore region to accurately calculate the pressure distribution and shear rate of polymer *** combination of polymer behavior characterizations and numerical flow simulations are applied,resulting in the calculation for the distribution of water saturation,polymer concentration and reservoir *** with the polymer flooding well with uniform fracture conductivity,this non-uniform fracture conductivity model exhibits the larger pressure difference,and the shorter bilinear flow period due to the decrease of fracture flow ability in the far-wellbore *** field case of the fall-off test demonstrates that the proposed method characterizes fracture characteristics more accurately,and yields fracture half-lengths that better match engineering reality,enabling a quantitative segmented characterization of the near-wellbore section with high fracture conductivity and th

关键词： Polymer flooding Non-Newtonian fluid Non-uniform fracture conductivity Two-phase flow Pressure transient analysis

17-Dehydroxyholothurin A, a New Sulfated Triterpene Glycoside from Sea Cucumber Holothuna impatiens

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Chinese Chemical Letters 2006年第11期17卷 1454-1456页

作者： Peng SUN Yang Hua YI Ling LI Min GUI Hai Feng TANG Da Zhi zhang shi long zhang Research Center for Marine Drugs Pharmacy School Second Military Medical University Shanghai 200433 Division of Antitumor Pharmacology State Key Laboratory of Drug Research Shanghai Institute of Materia Medica Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai 201203 Department of Pharmacy Xijing Hospital 4th Military Medical University Xi＇an 710032 Departrnent of Organic Chemistry Pharmacy School Second Military Medical University Shanghai 200433

Abstract： A new sulfated triterpene glycoside named as 17-dehydroxyholothurin A 1 was isolated from the sea cucumber Holothuria impatiens. Its structure was elucidated on the basis of spectroscopic data （2D NMR and MS） and chemical evidence. Compound 1 showed cytotoxic activity against cancer cell lines MKN-28, MFC-7, KB, HL-60 and Hep G2 with IC50 values of 1.98, 4.53, 2.01, 4.69 and 2.80 ×10^-6 tool/L, respectively.

关键词： Sea cucumber Holothuria impatiens 17-dehydroxyholothurin A triterpene glycoside.

Analysis of QTLs for erucic acid and oil content in seeds on A8 chromosome and the linkage drag between the alleles for the two traits in Brassica napus

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Journal of Genetics and Genomics 2010年第4期37卷 231-240页

作者： Zhengying Cao Fang Tian Nian Wang Congcong Jiang Bing Lin Wei Xia Jiaqin shi Yah long Chunyu zhang Jinling Meng National Key Laboratory of Crop Genetic Improvement Huazhong Agricultural University Wuhan 430070 China

The history of canola breeding began with the discovery of germplasm with low erucic acid content in seeds of spring forage cultivar in the 1950＇s. FAEI mutations led to a dramatic decrease of the seed erucic acid content in Arabidopsis thaliana. The products of the two FAE1 loci, ***1 and ***1, showed additive effects to the level of erucic acid content in oilseed rape. Previous research be- lieved that the pleiotropy of FAE1 was responsible for the decrease in seed oil content along with the reduction of seed erucic acid content in the modem cultivars. TN DH population was developed from a canola cultivar Tapidor and a Chinese traditional cultivar Ningyou7. The population had been tested in 10 and 11 environments to map QTLs for the erucic acid content and oil content in seeds. As the map resolution increased, a novel QTL for seed erucic acid content was revealed, after Meta-analysis, 7 cM away from the most significant seed erucic acid content QTL where ***1 is located. Seven independent QTLs for seed oil content （qOC） were detected around the two seed erucic acid content QTLs （qEA） across 39.20 cM on linkage group AS. Two of the qOCs co-localized with the two qEAs, respectively, and were detected in a single environment. The other five qOCs were detected in 10 of 11 environments independent ofqEAS. Alleles from Tapi- dot in all the QTLs at the （~39.20 cM region contributed negative effects to either erueic acid content or oil content in seeds. Parallel, geno- typing showed that on 5 of the 7 QTLs regions, Tapidor alleles had the same genotypes with that in ＇Liho＇, the original low seed erucic acid content source. Through rounds of crossbreeding with oil-cropped eultivars and intensive selection for multi generations, Tapidor still had the inferior alleles for low seed oil content from ＇Liho＇, the forage rape. This showed a strong linkage drag of low seed oil content, which was controlled by the five qEA-independent qOCs, with low seed erucic acid

关键词： seed oil content enlcic acid content QTL genetic drag

Alloy strategy to synthesize Pt-early transition metal oxide interfacial catalysts

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Nano Research 2024年第4期17卷 3390-3397页

作者： shi-long Xu Hang Nan Wanqun zhang Yue Lin Sheng-Qi Chu Hai-Wei Liang Hefei National Research Center for Physical Sciences at the Microscale Department of ChemistryUniversity of Science and Technology of ChinaHefei 230026China School of Materials and Chemical Engineering Anhui Jianzhu UniversityHefei 230601China Institute of High Energy Physics Chinese Academy of SciencesBeijing 100049China

Metal oxide supported metal catalysts show promising catalytic performance in many industry-relevant ***,the enhancement of performance is often limited by the insufficient metal/metal oxide *** this work,we demonstrate a general synthesis of Pt-early transition metal oxide(Pt-MO_(x),M=Ti,Zr,V,and Y)catalysts with rich interfacial sites,which is based on the air-induced surface segregation and oxidation of M in the supported Pt-M alloy *** characterizations verify the dynamic structural response of Pt-M alloy catalysts to air and the formation of Pt-MO_(x) catalysts with abundant interfacial *** prepared Pt-TiO_(x) interfacial catalysts exhibit improved performance in hydrogenation reactions of benzaldehyde,nitrobenzene,styrene,and furfural,as a result of the heterolytic dissociation of H_(2) at Pt-metal oxide interfacial sites.

关键词： Pt-early transition metal oxide interfacial catalyst alloy oxidation strategy interfacial sites hydrogenation reactions heterolytic dissociation

Non-adiabatic holonomic quantum operations in continuous variable systems

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Science China(Physics,Mechanics & Astronomy) 2024年第6期67卷 12-19页

作者： Hao-long zhang Yi-Hao Kang Fan Wu Zhen-Biao Yang shi-Biao Zheng Fujian Key Laboratory of Quantum Information and Quantum Optics College of Physics and Information EngineeringFuzhou UniversityFuzhou 350116China

Quantum operations by utilizing the underlying geometric phases produced in physical systems are favoured due to their potential *** a system in a non-degenerate eigenstate undergoes an adiabatically cyclic evolution dominated by its Hamiltonian,it will get a geometric phase,referred to as the Berry *** a non-adiabatically cyclic evolution produces an Aharonov-Anandan geometric *** two types of Abelian geometric phases are extended to the non-Abelian cases,where the phase factors become matrix-valued and the transformations associated with different loops are *** and non-Abelian(holonomic)operations are prevalent in discrete variable systems,whose limited(say,two)energy levels,form the *** their developments in continuous systems have also been investigated,mainly due to that,bosonic modes(in,such as,cat states)with large Hilbert spaces,provide potential advantages in fault-tolerant quantum *** we propose a feasible scheme to realize non-adiabatic holonomic quantum logic operations in continuous variable systems with cat *** construct arbitrary single-qubit(two-qubit)gates with the combination of single-and two-photon drivings applied to a Kerr Parametric Oscillator(KPO)(the coupled KPOs).Our scheme relaxes the requirements of the previously proposed quantum geometric operation strategies in continuous variable systems,providing an effective way for quantum control.

关键词： cat qubit continuous variable systems non-Abelian

First-principles study of the relationship between the formation of single atom catalysts and lattice thermal conductivity

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Chinese Chemical Letters 2024年第6期35卷 502-506页

作者： Chaozheng He Pei shi Donglin Pang Zhanying zhang long Lin Yingchun Ding Department of Chemistry and Chemical Engineering Liaocheng UniversityLiaocheng 252059China Henan Key Laboratory of Materials on Deep-Earth Engineering School of Materials Science and EngineeringHenan Polytechnic UniversityJiaozuo 454000China School of Materials Science and Engineering Henan Polytechnic UniversityJiaozuo 454000China Department of Basic Medicine North Sichuan Medical CollegeNanchong 637000China

Single atom catalysts(SACs)have been in the forefront of catalysts research because of their high efficiency and low cost and provide new ideas for development of renewable energy conversion and storage ***,the relationship between the intrinsic properties of materials such as lattice thermal conductivity and catalysis remains to be *** this work,the lattice thermal conductivity of BN and graphene was calculated by Sheng *** addition,the adsorption properties of 3d-TM(TM=V,Cr,Mn,Fe,Co,Ni)on BN and graphene were investigated using first-principles methods,and it was found that Ni atom can form relatively stable SACs compared to other *** molecular dynamics(MD)simulation and migration barrier of Ni loaded on BN and graphene were *** study found that graphene has higher thermal conductivity and is easier to form SACs than BN,but the SACs formed on BN surface have higher thermodynamic stability.

关键词： First-principles calculation Thermal conductivity Single atom catalysts Graphene BN

Effects of rafting on the meso deformation and fracture behaviour of a Ni-based single crystal superalloy at room temperature: In-situ observation and simulation

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Science China(Technological Sciences) 2024年第7期67卷 2133-2146页

作者： TAN long YANG XiaoGuang shi DuoQi FAN YongSheng shi Yi School of Energy and Power Engineering Beihang UniversityBeijing 102206China Research Institute of Aero-Engine Beihang UniversityBeijing 102206China National Key Laboratory of Science and Technology on Aero-Engine Aero-Thermodynamics Beihang UniversityBeijing 102206China School of Materials Science&Engineering Shanghai Jiao Tong UniversityShanghai 200240China

Microstructural rafting of Ni-based single-crystal(SC) superalloys is inevitable at elevated temperatures during long-term service with mechanical loading, which significantly affects the mechanical behaviour of the material. In this study, the effects of rafting on the mesodeformation and fracture behaviour of a Ni-based SC superalloy under cyclic and tensile loads were investigated using in situ scanning electron microscopy(SEM), digital image correlation(DIC), and crystal plasticity finite element method(CP-FEM) simulations. The results indicated that the tensile strength decreased significantly in the rafted specimens. In the cyclic tests, both the virgin and rafted specimens showed an increase in the maximum shear strain with cycle number. The interaction of cross-slip bands was captured by in situ SEM-DIC around the micro-notch of the virgin specimens during the tensile test, while a more homogeneous local deformation field was observed in the rafting specimens. In addition,the fracture behaviour was strongly influenced by the rafting morphology. The crack exhibited instantaneous and long-range fracture features along the octahedral plane as it propagated in the rafting specimen, whereas it deflected over a short distance between the crystallographic planes at an early stage in the virgin specimen, which is consistent with the CP-FEM ***, the CP-FEM results for the crack initiation direction on(111) dominant slip plane were consistent with the in situ SEM observations.

关键词： in-situ SEM-DIC Ni-based SC superalloys microstructural rafting deformation crack path CP-FEM

Metallurgy and Solidification Microstructure Control of Fusion-Based Additive Manufacturing Fabricated Metallic Alloys:A Review

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Acta Metallurgica Sinica(English Letters) 2024年第1期37卷 29-53页

作者： Qiang Li Xing-Ran Li Bai-Xin Dong Xiao-long zhang shi-Li Shu Feng Qiu Lai-Chang zhang Zhi-Hui zhang Key Laboratory of Bionic Engineering(Ministry of Education) and College of Bionic Science and EngineeringJilin UniversityChangchun130022China Institute of Structured and Architected Materials Liaoning Academy of MaterialsShenyang110167China Key Laboratory of Automobile Materials Ministry of Education and Department of Materials Science and EngineeringJilin UniversityChangchun130025China School of Mechanical and Aerospace Engineering Jilin UniversityChangchun130025China School of Engineering Edith Cowan University270 Joondalup DriveJoondalupPerthWA6027Australia

The metal-based additive manufacturing(AM),also referred to as metal 3D printing,has drawn particular interest because it enables direct creation,aided by computationally-directed path design,of intricate components with site-specific compositions and geometrical requirements as well as low buy-to-fly *** the last two decades,the objective of this revolutionary technology has been shifting from only“rapid prototyping”to advanced manufacturing of special high-end products or devices,which,in many aspects,outperform conventional manufacturing *** fusion-based AM,significant progress has been achieved in understanding the processing window of macroscopic scales,non-equilibrium metallurgy of mesoscale scales,and grain evolution of microscopic *** the versatile capacity of AM facilitates new avenues for discovering advanced materials and structures,their potential has still not been fully *** the unique non-equilibrium solidification during the AM process,coarse columnar grains with strong textures are usually developed along the build direction,which downgrades the mechanical *** push the limits of this digital manufacturing,this review attempts to provide in-depth and comprehensive overviews of the recent progress in understanding the evolution and control of the as-built microstructure that has been made recently and the challenges encountered during the AM process.

关键词： Additive manufacturing Temperature field Microstructure control Nanoparticles Functionally graded materials