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Science China(Physics,Mechanics & Astronomy) 2009年第7期52卷 978-986页

作者： wang aimin PANG Hua Institute of Applied Magnetics Key Laboratory for Magnetism and Magnetic Materials of the Ministry of EducationLanzhou UniversityLanzhou 730000China

The magnetic anisotropy field in thin films with in-plane uniaxial anisotropy can be deduced from the VSM magnetization curves measured in magnetic fields of constant magnitudes. This offers a new possibility of applying rotational magnetization curves to determine the firstand second-order anisotropy constant in these films. In this paper we report a theoretical derivation of rotational magnetization curve in hexagonal crystal system with easy-plane anisotropy based on the principle of the minimum total energy. This model is applied to calculate and analyze the rotational magnetization process for magnetic spherical particles with hexagonal easy-plane anisotropy when rotating the external magnetic field in the basal plane. The theoretical calculations are consistent with Monte Carlo simulation results. It is found that to well reproduce experimental curves, the effect of coercive force on the magnetization reversal process should be fully considered when the intensity of the external field is much weaker than that of the anisotropy field. Our research proves that the rotational magnetization curve from VSM measurement provides an effective access to analyze the in-plane anisotropy constant K3 in hexagonal compounds, and the suitable experimental condition to measure K3 is met when the ratio of the magnitude of the external field to that of the anisotropy field is around 0.2.

关键词： rotational magnetization curve magnetocrystalline anisotropy in-plane anisotropy constant K3

ON THE DIVIDED DIFFERENCE FORM OF FAA DI BRUNO＇S FORMULA Ⅱ

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Journal of Computational Mathematics 2007年第6期25卷 697-704页

作者： Xinghua wang aimin Xu Department of Mathematics Zhejiang University Hangzhou 310027 China

In this paper, we consider the higher divided difference of a composite function f（g（t）） in which g（t） is an s-dimensional vector. By exploiting some properties from mixed partial divided differences and multivariate Newton interpolation, we generalize the divided difference form of Faà di Bruno＇s formula with a scalar argument. Moreover, a generalized Faà di Bruno＇s formula with a vector argument is derived.

关键词： Bell polynomial Faà di Bruno's formula Mixed partial divided difference,Multivariate Newton interpolation.

Electromagnetic parameters and microwave-absorption properties for the mixtures of mechanically milled spherical and flaky carbonyl iron powders

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Acta Metallurgica Sinica(English Letters) 2012年第3期25卷 201-206页

作者： Jinghua HE Wei wang aimin wang Jianguo GUAN State Key Laboratory of Advanced Technology for Materials Synthesis and Processing Wuhan Universityof TechnologyWuhan 430070China

The electromagnetic parameters were measured for the mixtures of mechanical milled carbonyl iron powders （CIPs） with different mass ratios of spheroid-like particles to flake-shape particles. The results indicate that mixing the sphere-like CIP particles with flake-shaped CIPs can be used to adjust effectively the electromagnetic parame- ters and enhance the absorption property in high frequency. In addition, a theoretic simulation based on the principle of superposition was carried out and compared with the microwave measurement results, indicating that the simple principle of superpo- sition can not reflect truly the internal interaction mechanism in the composites with different particle shapes.

关键词： Carbonyl iron Mechanical milling Electromagnetic property Microwave-absorption property

Layout Planning Technology of Cellular Manufacturing System Based on Process Interconnection Analysis

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Chinese Journal of Mechanical Engineering 2011年第6期24卷 1035-1044页

作者： CHEN Huawei wang aimin NING Ruxin SHAO Canxia Digital Design and Manufacturing Laboratory Beijing Institute of TechnologyBeijing 100081China

With sustaining change of production mode,layout planning is no longer a thing built once for *** layout(CL) is becoming a hotspot in the research field of manufacturing system *** researches on layout planning are mainly concentrating on aspects of layout arithmetic,style and evaluation,*** seldom efforts are paid to CL and its specific problems as cell formation(CF),equipment sharing and CL *** problem analyzing of layout in cellular manufacturing system(CMS),research approach of cell formation,interactive layout and layout analysis threaded with process interconnection relationship(PIR) is *** key technologies in CL like CF technology based on similarity analysis of part processes,interactive visual layout technology,layout evaluation technology founded on PIR analysis and algorithm of cell equipment sharing are put *** the background of one enterprise which encounters problems of low utility of key equipments and disperse material logistic,an example of four-cell layout is *** CL adjustment and analysis results show that equipment with high level of sharing degree should be disposed around the boundary of its main cell,and be near to other sharing cells as possible; process route should be centralized by all means,so equipment adjustment is to be implemented along direction that route intersection can be decreased; giving consideration to the existence of discrete cell,logistic route and its density should be centralized to cells *** proposed research can help improve equipment utility and material logistic efficiency of CL,and can be popularized to other application availably.

关键词： cellular manufacturing system, layout planning process interconnection relationship cell formation equipment sharing interactive layout

A Novel Scalable Fault-Tolerant Control Design for DC Microgrids With Nonuniform Faults

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IEEE/CAA Journal of Automatica Sinica 2024年第8期11卷 1886-1888页

作者： aimin wang Minrui Fei Dajun Du Yang Song Shanghai Key Laboratory of Power Station Automation Technology the School of Mechatronic Engineering and AutomationShanghai UniversityShanghai 200072China

Dear Editor,The existing control schemes for microgrids(MGs)face challenges in effectively addressing plugging in/out operations under uncertain power lines and *** tackle this issue,this letter proposes a novel scalable fault-tolerant control(FTC)strategy for DC *** developing a structured Lyapunov matrix(SLM),a decoupled FTC method is introduced to mitigate the adverse effects of uncertain lines and nonuniform ***,global stability is ensured by deriving local rules expressed as linear matrix inequalities(LMIs)that solely depend on local *** new distributed generation unit(DGU)introduces only one additional condition of this nature,allowing the stability rules to scale with topology ***,the effectiveness of the proposed scheme is illustrated through simulations conducted using the MATLAB/SimPowerSystems toolbox.

关键词： stability letter operations

Integrated Manufacturing Cell Formation Technology Orienting Multi-product Type and Variant Volume Production

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Chinese Journal of Mechanical Engineering 2011年第1期24卷 12-22页

作者： CHEN Huawei wang aimin NING Ruxin SHAO Canxia Digital Design and Manufacturing Laboratory Beijing Institute of Technology Beijing 100081 China

What is pursued by multi-product type and variant volume（MPTVV） production is rapid response and quick switching,so that structure of transferring line in manufacturing system is no longer *** formation（CF） algorithm is the key technology of cellular manufacturing system（CMS）.Currently,CF methods are mainly extended on the idea of group technology（GT） that covers a lot on analysis of resource capability matching and its *** constraints are considered,but seldom utilized *** to the problem of manufacturing cell（MC） formation under MPTVV production mode,integrated formation technologies for typical MC as group type of cell（GC）,flow type of cell（FC） and inherited cell（IC） are presented based on technical analysis of *** to practical production constraints like delivery time,product batch,equipment ability,key machine,key part and machine sharing,etc,an integrated formation model is constructed and internal interrelations of these constraints are analyzed ***,formation goals of types of MCs and their formation procedures under joint effect of formation constraints and rules are *** case study,three highly balanced GC are formed first;then FC formation are implemented based on the same data which indicate good balancing effect of cell load and flow-style production for key tasks;When task is adjusted,a new scheme is constructed on the result of FC configuration by using IC formation method,and more optimal performance of flow-style production is *** proposed comparative study of different type of cells strongly explains the validation of integrated MC formation in support of rapid manufacturing resource transformation under MPTVV production mode.

关键词： multi-product type and variant volume production cell formation flow style manufacturing cell inheriting manufacturing cell

Prediction of medium-to-coal ratio effect in a dense medium cyclone by using both traditional and coarse-grained CFD-DEM models

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Particuology 2022年第9期20卷 44-56页

作者： Zhaoyang Li Kaiwei Chu Zongqing Zhou Yixiong Feng aimin wang School of Mechanical Engineering Zhejiang UniversityHangzhou 310027China School of Qilu Transportation Shandong UniversityJinan 250002China Shandong Iron and Steel Group Co. Ltd.Jinan 250101China State Key Lab Fluid Power&Mechatron Syst Zhejiang UniversityHangzhou 310027China4.Hengda Fuji Elevator Co.Ltd.Huzhou 313009China JITRI Institute for Process Modelling and Optimization Suzhou 215123China

Dense medium cyclone(DMC)is the working horse in coal *** practice,it is usually operated under constant pressure and the operational conditions(mainly medium-to-coal(M:C)ratio and oper-ational pressure)need to be adjusted according to coal washability data(mainly coal particle size and density distributions).Nonetheless,until now it is still not well understood how the M:C ratio would affect the performance of DMCs especially under the practical *** this work,the effect of M:C ratio is for the first time numerically studied under conditions similar to plant operation by using both tra-ditional and coarse-grained(CG)combined approach of computational fluid dynamics(CFD)and discrete element method(DEM),called as traditional CFD-DEM and CG CFD-DEM,in which the flow of coal par-ticles is modelled by DEM or CG DEM which applies Newton's laws of motion to individual particles and that of medium flow by the conventional CFD which solves the local-averaged Navier-Stokes equations,allowing consideration of particle-fluid mutual interaction and particle-particle ***,impulse and momentum connection law is used to achieve energy conservation between traditional CFD-DEM and CG *** is found that under constant pressure,the M:C ratio affects DMC perfor-mance *** specific effect depends on coal washability or coal *** extremely low M:C ratio,the phenomenon that high-quality coal product is misplaced to reject is successfully repro-duced,which has been observed in plants in Australian coal industry and called as"low-density tail".Moreover,strategies are proposed to mitigate the"low-density tail"phenomenon based on the model.

关键词： Dense medium cyclone Medium-to-coal ratio Discrete element method Computational fluid dynamics Low-density coal tail

Experimental study of freak waves due to three-dimensional island terrain in random wave

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Acta Oceanologica Sinica 2019年第6期38卷 92-99页

作者： Li Zou aimin wang Zhen wang Yuguo Pei Xiaolong Liu School of Naval Architecture Dalian University of TechnologyDalian 116024China State Key Laboratory of Structural Analysis for Industrial Equipment Dalian University of TechnologyDalian 116024China Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Shanghai 200240China School of Mathematic Science Dalian University of TechnologyDalian 116024China China Ship Scientific Research Center Wuxi 214082China

An experimental study is carried out for waves passing an isolated reef terrain in a wave tank. A three-dimensional model of a representative and isolated reef terrain in the West Pacific is built. Random wave trains with various periods and wave heights are generated by a wave maker using the improved JONSWAP spectrum. It is observed that there are different kinds of generation processes and waveforms of freak waves. The freak wave factor Hm/Hs (where Hm is the maximum wave height of wave series, and Hs is significant wave height) is analyzed in detail, in terms of the skewness, kurtosis and water depth, as well as the relationship between freak wave height H& and skewness. The freak wave factor Hm/Hs is found to be in positive correlation with the kurtosis, while larger H[x tends to be related with bigger skewness. The rapid variation of water depth, such as slope and seamount, contributes to the occurrence probability of freak waves.

关键词： freak waves random wave skewness and kurtosis three-dimensional island terrain

Eukaryotic food sources analysis in situ of tropical common sea cucumber Holothuria leucospilota based on 18S rRNA gene high-throughput sequencing

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Journal of Oceanology and Limnology 2023年第3期41卷 1173-1186页

作者： Yue ZHANG Fei GAO Qiang XU Yanan wang Haiqing wang aimin wang State Key Laboratory of Marine Resource Utilization in South China Sea Hainan UniversityHaikou 570228China College of Marine Science Hainan UniversityHaikou 570228China

Sea cucumber Holothuria leucospilota is one of the most widespread tropical holothurian *** this study,eukaryotic organism composition in foregut and hindgut contents of *** and surrounding sediments was assessed by 18S rRNA gene high-throughput *** richness and diversity in the habitat sediments were significantly higher than those in foregut and hindgut contents of the sea cucumbers(P<0.05).The foregut content group,hindgut content group,and marine sediment group sequences were respectively assigned to 18.20±1.32,19.40±1.03,and 21.80±0.37 *** the foregut contents,Nematoda(20.18%±9.59%),Mollusca(16.12%±10.49%),Chlorophyta(10.04%±4.85%),Annelida(8.72%±10.93%),Streptophyta(8.46%±4.65%),and Diatomea(5.99%±2.01%)were the predominant phyla,which showed the eukaryotic food sources of *** were primarily belong to the above *** predominant phyla in the hindgut contents were Streptophyta(45.55%±17.32%),Mollusca(4.93%±4.82%),Arthropoda(5.37%±3.08%),Diatomea(3.88%±2.34%),and Chlorophyta(3.79%±1.59%);and Annelida(37.80%±17.00%),Arthropoda(24.49%±12.53%),Platyhelminthes(7.14%±3.02%),Nematoda(4.14%±0.91%),and Diatomea(5.11%±1.35%)had large contents in the *** comparatively high content of Paris genus in phylum Streptophyta in foregut contents indicated that land plants were one of the primary food sources of ***,however the significantly higher contents of Streptophyta in hindgut contents than that in foregut contents might suggest a large part of the terrigenous detritus ingested might not be digested by *** and PCoA analysis revealed that eukaryotic organism composition differed significantly between foregut contents of *** and ambient sediments,indicating selective feeding feature of *** study provided useful references for artificial feed of tropical sea cucumbers and enhanced understanding of the ecological roles of detritus-feeding macrobenthos.

关键词： Holothuria leucospilota food source 18S rRNA gene gut content sediment

Atomic-scale Nb heterogeneity induced icosahedral short-range ordering in metallic glasses

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Journal of Materials Science & Technology 2022年第13期108卷 73-81页

作者： Yuhui Zhu Weizhen wang Yuanyuan Song Shiming Zhang Hong Li aimin wang Haifeng Zhang Zhengwang Zhu Shi-changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China School of Materials Science and Engineering University of Science and Technology of ChinaHefei 230026China CAS Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Shenyang National Laboratory for Materials Science Institute of Metal ResearchChinese Academy of SciencesShenyang 110016China Qingdao Yunlu Advanced Materials Technology Co. Ltd.Qingdao 266232China

The intrinsic origins and formation of atomic-scale structure in multicomponent alloys remain largely unknown owing to limited simulations and inaccessible ***,we report the formation of three-dimensional periodicity from a disordered atomic-scale structure to an imperfect/perfect ordered cluster and finally to long-range translational and rotational symmetry coupled with Nb *** atomic-scale structural clustering and atomic arrangements involving solvent or solute atoms simultaneously occurred during isothermal annealing.A close relationship between atomic-scale structural evolution and composition variation has important implications in depicting the chemical and topological packing during the early crystallization stage in metallic *** work can provide a comprehensive understanding of how short-range orders evolve into long-range periodicity and will further shed light on the origins and nature of metallic glasses.

关键词： Metallic glasses Isothermal annealing Atomic-scale Structural ordering Nb heterogeneity