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Wrinkle analysis of a space planar film reflect-array

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2011年第1期12卷 24-32页

作者： wei-wei XIAO Wu-jun CHEN Gong-yi FU Space Structures Research Centre Shanghai Jiao Tong University Shanghai 200030 China

The presence of wrinkles in a membrane is the main factor that induces surface errors on space planar film reflect-arrays. Based on the commercial finite element (FE) package ABAQUS, a numerical procedure for membrane wrinkle analysis was set up, and used to analyze a square planar film reflect-array under pure shear force to evaluate its induced wrinkle characteristics. First, the effect of shear force on the wrinkle pattern of the array was studied and validated by experiment. Second, the effect of prestress was studied. When the prestress increases, the quantity of the wrinkles increases, and the amplitude of the wrinkles decreases. Third, the influence of the boundary conditions was investigated. A frame side edge structure has a relatively smooth surface, but also relatively high stress. Finally, the behavior of a joint seam was analyzed. The results indicate that a joint band has a significant influence on the wrinkle pattern of the membrane.

关键词： Space planar film reflect-array Wrinkle analysis Joint seam

Modeling and identification of magnetostrictive hysteresis with a modified rate-independent Prandtl-Ishlinskii model

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Chinese Physics B 2018年第9期27卷 626-634页

作者： wei Wang jun-en Yao School of Instrumentation Science and Opto-electronics Engineering Beihang UniversityBeijing 100083China School of Physics and Nuclear Energy Engineering Beihang UniversityBeijing 100083China Laboratory of Micro-nano Measurement Manipulation and PhysicsBeihang UniversityBeijing 100083China

This paper presents a modified rate-independent Prandtl-Ishlinskii （MRIPI） model based on the Fermi-Dirac distri- bution for the asymmetric hysteresis description of magnetostrictive actuators. Generally, the classical Prandtl-Ishlinskii （CPI） model can hardly describe the asymmetric hysteresis. To overcome this limitation, various complex operators have been developed to replace the classical operator. In this study, the proposed MRIPI model maintains the classical operator while a modified input function based on the Fermi-Dirac distribution is presented to replace the classical input function. With this method, the MRIPI model can describe the asymmetric hysteresis of magnetostrictive actuators in a relatively simple mathematic format and has fewer parameters to be identified. A velocity-based sine cosine algorithm （VSCA） is also proposed for the parameter identification of the MRIPI model. To verify the validity of the MRIPI model, experiments are performed and the results are compared with those of the existing modeling methods.

关键词： Prandtl-Ishlinskii model velocity-based sine cosine algorithm asymmetric hysteresis nonlinear-ity magnetostrictive actuator

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针刺康复综合治疗脑卒中后吞咽障碍临床观察

上海针灸杂志 2016年第10期35卷 1166-1169页

作者：李宝栋白晶崔景军司卫军宋佳张玉曼河北省沧州中西医结合医院沧州061001

目的观察针刺康复综合治疗脑卒中后吞咽障碍的疗效及对患者吞咽功能神经通路各环节的影响。方法选取99例脑卒中后吞咽障碍患者,采用前瞻性随机对照研究方法,分成针康综合组、咽部针刺组和对照组,分别为33例、34例、32例。针康综合组采... 详细信息

目的观察针刺康复综合治疗脑卒中后吞咽障碍的疗效及对患者吞咽功能神经通路各环节的影响。方法选取99例脑卒中后吞咽障碍患者,采用前瞻性随机对照研究方法,分成针康综合组、咽部针刺组和对照组,分别为33例、34例、32例。针康综合组采用皮层咽部舌根针刺法及基础治疗,咽部针刺组采用吞咽穴单穴治疗及基础治疗,对照组仅应用基础治疗,每日1次,疗程为4星期。收集治疗前后FOIS评分及CNSAT评分,并进行统计学分析。结果针康综合组治疗后CNSAT各项评分均较治疗前明显改善(P<0.01),咽部针刺组治疗前后CNSAT各项评分比较差异有统计学意义(P<0.05),针康综合组治疗后CNSAT各项评分与咽部针刺组及对照组比较差异有统计学意义(P<0.01),咽部针刺组治疗后CNSAT各项评分与对照组比较差异有统计学意义(P<0.05);各组治疗后FOIS评分较治疗前均有提高,针康综合组治疗前后比较差异有显著统计学意义(P<0.01),咽部针刺组治疗前后比较差异有统计学意义(P<0.05);但针康综合组和咽部针刺组治疗后FOIS评分均高于对照组(P<0.01,P<0.05)。结论采用皮层咽部舌根序贯针刺法配合康复手法,能够有效干预脑卒中后口咽相各种吞咽问题,改善口咽相吞咽障碍患者进食能力,减少误吸风险。

关键词：卒中吞咽障碍针刺康复训练头针序贯针刺法

Influence of aeration and initial water thickness on axial velocity attenuation of jet flows

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2013年第5期14卷 362-370页

作者： Wang-ru wei jun DENG Bin LIU State Key Laboratory of Hydraulics and Mountain River Engineering Sichuan University Hydro-China Kunming Engineering Corporation

With the development of ski-jump energy dissipation for high and large discharge among the hydraulic projects,the effects of characteristics of water flow on energy dissipation are increasingly *** the present study,the effects of aeration and the initial water thickness on axial velocity attenuation of jet flow were analyzed,using variance analysis and numerical calculated *** the analysis of test data,both of the air concentration and initial water thickness are sensitive factors for the axial velocity attenuation of jet flow along the axial way,and there is no significant interaction effect between the aeration and initial water *** has a more significant effect on the axial velocity attenuation of jet *** the initial water thickness of jet flow can reduce the length of jet core,and make the initial position of axial velocity attenuation closer to the nozzle *** numerical calculation results show that aeration can contribute to the enhancement of entrainment ability of jet flow,which may improve the interaction between jet flow and *** ski-jump energy dissipation among the hydraulic projects,combining aeration with decreasing initial water thickness of jet flow is an effective way to enhance the rate of axial velocity attenuation.

关键词： Velocity Aeration Initial water thickness Jet flows

Higher alcohols synthesis from syngas over lanthanum-promoted CuZnAl catalyst

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Journal of Energy Chemistry 2018年第1期27卷 319-325页

作者： Xuan Deng Yong-jun Liu wei Huang Key Laboratory of Coal Sdence and Technology of Ministry of Education and Shanxi Province Taiyuan University of TechnologyTaiyuan 030024ShanxiChina Center of Information Management and Development Taiyuan University of TechnologyTaiyuan 030024ShanxiChina

CuZnAl catalysts with different La loadings were prepared by a complete liquid phase method and tested for higher alcohols（C_（2＋）OH） synthesis from syngas at the conditions of 250–290 ℃, 4.5 MPa, feed low rate = 150 mL/min and H_2/CO = 2. The catalysts were characterized by XRD, H_2-TPR, NH_3-TPD, N_2 adsorption, XPS, and TEM techniques. Characterization results showed that the incorporation of La into CuZnAl catalysts resulted in the decrease of crystallite size of Cu^0 and a strong interaction among copper and zinc or aluminum oxides. Especially, the incorporation of La increased the amount of weak acid and the Cu content on catalyst surface, which was speculated to contribute the formation of higher alcohols. Among these La-promoted CuZnAl catalysts, the La0.1 catalyst exhibited the best catalytic performance and the selectivity to higher alcohols reached above 60% when the reaction temperature was 290 ℃.

关键词： Syngas C2+OH CuZnAl La promoter Slurry bed reactor

Influence of reaction of Al2O3 and carbonaceous materials in Al2O3–C refractories on aluminum and carbon pick-up of iron

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Journal of Iron and Steel Research International 2020年第1期27卷 55-61页

作者： Yao-wu wei Yan-jun Dong Tao Zhang jun-feng Chen Wen Yan The State Key Laboratory of Refractories and Metallurgy Wuhan University of Science and TechnologyWuhan 430081HubeiChina

Carbon-containing Al2O3 refractory crucibles and pure Al2O3 refractory crucible were fabricated to study the effect of carbon-containing Al2O3-C refractories on aluminum and carbon pick-up of *** crucibles with pure iron powder were placed in a vacuum induction furnace and heated at 1600℃ for regular time under flowing argon *** Al and C contents of iron samples were analyzed,and iron samples were also investigated using a field scanning electron microscope equipped with energy-dispersive *** results showed that carbon materials did affect the interac?tion of(Al2O3-C)/Fe system,carbothermal reduction in alumina occurred in the reaction system and the extent of reactions depended on the kinds of carbon materials.

关键词： Al2O3-C refractory Liquid iron Aluminum pick-up Carbon pick-up Carbothermal reduction

Deformation behavior and plastic instability of boronized Al0.25CoCrFeNi high-entropy alloys

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International Journal of Minerals,Metallurgy and Materials 2020年第10期27卷 1363-1370页

作者： Jin-xiong Hou Jing Fan Hui-jun Yang Zhong Wang jun-wei Qiao College of Materials Science and Engineering Taiyuan University of TechnologyTaiyuan 030024China Key Laboratory of Interface Science and Engineering in Advanced Materials(Ministry of Education Taiyuan University of TechnologyTaiyuan 030024China

Using thermochemical treatments,boronized layers were successfully prepared on Al0.25CoCrFeNi high-entropy alloys(HEAs).The thickness of the boronized layers ranged widely from 20 to 50μm,depending on the heat treatment *** remarkably improved the surface hardness from HV 188 to HV 1265 after treating at 900°C for 9 ***,boronizing enhanced the yield strength of HEAs from 195 to 265 MPa but deteriorated the tensile *** crackings in the boride layers significantly decreased the *** insufficient work-hardening capacity essentially facilitated the plastic instability of the boronized *** decreasing substrate thickness,the fracture modes gradually transformed from dimples to quasi-cleavage and eventually to cleavage.

关键词： boronizing high-entropy alloys boride layers tensile strength cleavage fracture

Cumulative prospect theory-based user equilibrium model with stochastic perception errors

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Journal of Central South University 2016年第9期23卷 2465-2474页

作者： WANG wei SUN Hui-jun Key Laboratory of Urban Transportation Complex Systems Theory and Technology of Ministry of Education Beijing Jiaotong University Beijing 100044 China

The cumulative prospect theory(CPT) is applied to study travelers' route choice behavior in a degradable transport network. A cumulative prospect theory-based user equilibrium(CPT-UE) model considering stochastic perception error(SPE) within travelers' route choice decision process is developed. The SPE is conditionally dependent on the actual travel time distribution, which is different from the deterministic perception error used in the traditional logit-based stochastic user equilibrium. The CPT-UE model is formulated as a variational inequality problem and solved by a heuristic solution algorithm. Numerical examples are provided to illustrate the application of the proposed model and efficiency of the solution algorithm. The effects of SPE on the reference point determination, cumulative prospect value estimation, route choice decision and network performance evaluation are investigated.

关键词： cumulative prospect theory user equilibrium stochastic perception error variational inequality

Information gain based sensor search scheduling for low-earth orbit constellation estimation

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Journal of Systems Engineering and Electronics 2011年第6期22卷 926-932页

作者： Bo Wang jun Li wei An Yiyu Zhou School of Electronics and Engineering National University of Defense Technology Changsha 410073 R R. China Institute of Radar and Electronic Warfare Equipment Academy of Air Force Beijing 100085 P. R. China

This paper addresses the problem of sensor search scheduling in the complicated space environment faced by the low-earth orbit *** search scheduling methods based on the commonly used information gain are compared via simulations *** a novel search scheduling method in the scenarios of uncertainty observation is proposed based on the global Shannon information gain and beta density based uncertainty *** results indicate that the beta density model serves a good option for solving the problem of target acquisition in the complicated space environments.

关键词： low-earth orbit constellation sensor network scheduling algorithm information gain acquisition.