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Modeling and Simulation for Refueling Boom and Receiver inCoupled Mode

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Transactions of Nanjing University of Aeronautics and Astronautics 2017年第2期34卷 143-151页

作者： yang Chaoxing yang yu Lu yuping College of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106P.R.China Shanghai Institute of Spaceflight Control Technology Shanghai 200000P.R.China

In coupled mode,the major problem of boom refueling system is undesirable nozzle *** automated load alleviation system(ALAS)is needed to alleviate nozzle *** order to simulate dynamic of the system and to validate ALAS,dynamic model is *** models are established,which are the static model and the moving model,named after the two relative states between the fixed boom and the extension *** method is employed as main method considering system′s multi-body characteristics.D′Alembert′s principle is used to calculate nozzle *** is conducted to research the effects of position disturbance and velocity disturbance on nozzle *** indicate that position disturbance plays a more significant role in inducing nozzle loads.A fuzzy control law based ALAS is validated using the formulated *** is concluded that this model can simulate system dynamic and validate ALAS.

关键词： applied mechanics boom refueling nozzle load Kane method multi-body system

Accommodation of Curtailed Wind Power by Electric Boilers Equipped in Different Locations of Heat-supply Network for Power System with CHPs

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Journal of Modern Power Systems and Clean Energy 2021年第4期9卷 930-939页

作者： yunfeng Ma yang yu Zengqiang Mi School of Electrical and Electronic Engineering North China Electric Power UniversityBeijingChina Department of Electrical Engineering North China Electric Power UniversityBaodingChina

Electric boilers (EBs) provide an alternative method to deal with the accommodation of curtailed wind power. To pursue the minimum coal consumption in the system, a dispatching model integrating combined-heat-and-power (CHP) plants and EBs in different locations is developed, and the penalty of wind power curtailment and cost of EB employment are also incorporated in the model. The transmission loss and transportation lag of heat-supply network as well as the elasticity of heat load are considered in this paper. A kind of constrained programming with stochastic and fuzzy parameters is applied to deal with the uncertainties. A case in East Inner Mongolia in China demonstrates that the EBs are able to absorb curtailed wind power and supply the heat. The results indicate that the utility of EBs in the primary or secondary heat-supply network to accommodate curtailed wind power is mainly related to the efficiency of heat transmission and the elasticity of heat load.

关键词： Wind power combined-heat-and-power(CHP)unit electric boiler(EB) heat-supply network

Numerical Study on the Linear and Nonlinear Behavior of A Fluid-Filled Piezoelectric Membrane Under Gravity Waves

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China Ocean Engineering 2023年第5期37卷 768-780页

作者： LIU Chun-rong yang Wen-yu School of Civil Engineering and Architecture Xiamen University of TechnologyXiamen 361024China

This study integrated piezoelectric layers in a flexible membrane to form a piezoelectric membrane.A fluid-filled piezoelectric membrane,which can be used as breakwater and wave energy converter simultaneously,was *** mathematical models to describe the interactions of the waves with the piezoelectric membrane were *** dimensionless parameters to control the behavior of the piezoelectric membrane were *** mixed EulerianLagrangian method was employed to simulate the mathematical *** simulation code was *** on the simulation results,the effects of dimensionless elastic modulus of the membrane E^(*),tension of the membrane T_(0)^(*)and the resistance of the load R^(*)on the behavior of the piezoelectric membrane were *** E^(*)is small(E^(*)0.0001),the response of the piezoelectric membrane can be considered as *** linear response,the minimum transmission coefficient and maximum output electric power of the piezoelectric membrane can be achieved simultaneously by adjusting T_(0)^(*)and R^(*).For larger E^(*),nonlinear behavior of the piezoelectric membrane is *** some larger values of E^(*),working frequency of piezoelectric elements can reach eight times the wave *** these cases,higher output electric power can be achieved for smaller strain of the membrane.

关键词： wave energy breakwater piezoelectric membrane nonlinear

Comparative study of two lay-up sequence dispositions for flexible skin design of morphing leading edge

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Chinese Journal of Aeronautics 2021年第7期34卷 271-278页

作者： yu yang Zhigang WANG Shuaishuai Lyu Aircraft Strength Research Institute Xi’an 710065China

Morphing leading edge has great potential for noise abatement and aerodynamic efficiency *** drooping effect is realized by bending of the flexible skin which encloses to form the leading *** the flexible skin is often made of composite laminates of Glass Fiber Reinforced Plastics(GFRP),the lay-up sequences have become the determinant,which affects not only the morphing quality but also the manufacturing *** optimizing methods of layup sequences are comparatively *** the first method,the laminal quantities in 0,±45and 90vary independently,while in the second one,the concept of isotropic laminate unit[0/45/45/90]s is employed and the unit quantity is the unique *** evaluation demonstrates that for both methods there is insignificant impact to the overall morphing quality;however,specific concern is equally necessary for these two methods to the tip of the leading edge where the skin is at its minimum thickness and bears the most severe bending *** terms of computational efficiency and post-processing labor,the second method has better performance.

关键词： Composite laminates Flexible skin Glass fiber reinforced plastics Lay-up sequence Leading edge Morphing wing

RGCNU: Recurrent Graph Convolutional Network With Uncertainty Estimation for Remaining Useful Life Prediction

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IEEE/CAA Journal of Automatica Sinica 2023年第7期10卷 1640-1642页

作者： Qiwu Zhu Qingyu Xiong Zhengyi yang yang yu School of Big Data&Software Engineering Chongqing UniversityChongqing 400044 Key Laboratory of Dependable Service Computing in Cyber Physical Society Ministry of EducationChongqing 400044China School of Biology and Engineering Guizhou Medical UniversityGuiyang 550025China

Dear Editor,This letter focuses on the problem of remaining useful life(RUL)prediction of equipment. Existing graph neural network(GCN)-based approaches merely provide the point estimation of RUL. However,the estimated RUL often varies widely due to the model parameters and the noise in data. It is important to know the uncertainty in predictions for reliable risk analysis and maintenance decision *** map the relationship between noisy condition monitoring data and RUL with uncertainty.

关键词： letter estimation prediction

DISSIPATION OF WAVE ENERGY ON VERY MILD SLOPE

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Journal of Hydrodynamics 2000年第2期12卷 72-84页

作者： yu, yang Li, yucheng Dalian Univ of Technology Dalian China

The analysis and calculation of wave attenuation were presented when waves travel on sand bed, sand ripple bed and muddy bed, respectively. The dissipation of wave energy due to bottom percolation may be neglected on sand bed. The wave attenuation due to the friction of sand ripples is one order higher than that of flat sand bed. The energy loss of waves propagating on muddy bed is the largest. The equivalent coefficients of friction are calculated in order to compare with the solution by the bottom-friction model. Wave attenuation are also computed by the Bingham-model and the principle of conservation of wave energy flux on very mild muddy slope. The results coincide well with the wave information from the Lianyungang Wave Observation Station. Theoretical prediction indicates that the equivalent coefficients of friction increase with the decrease of water depth.

关键词： Attenuation Energy dissipation Models Slope stability Water waves

A Mathematical Model with Delays for Schistosomiasis Japonicum Transmission

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Chinese Annals of Mathematics,Series B 2010年第4期31卷 433-446页

作者： yu yang Dongmei XIAO Department of Mathematics Shanghai Jiao Tong University Shanghai 200240 China Corresponding author. Department of Mathematics Shanghai Jiao Tong University Shanghai 200240 China

A dynamic model of schistosoma japonicum transmission is presented that incorporates effects of the prepatent periods of the different stages of schistosoma into Baxbour＇s model. The model consists of four delay differential equations. Stability of the disease free equilibrium and the existence of an endemic equilibrium for this model are stated in terms of a key threshold parameter. The study of dynamics for the model shows that the endemic equilibrium is globally stable in an open region if it exists and there is no delays, and for some nonzero delays the endemic equilibrium undergoes Hopf bifurcation and a periodic orbit emerges. Some numerical results are provided to support the theoretic results in this paper. These results suggest that prepatent periods in infection affect the prevalence of schistosomiasis, and it is an effective strategy on schistosomiasis control to lengthen in prepatent period on infected definitive hosts by drug treatment （or lengthen in prepatent period on infected intermediate snails by lower water temperature）.

关键词： A mathematical model Schistosoma japonicum transmission Dynamics Globally stable Periodic orbits

Analysis of the shape of heavy droplets on flat and spherical surface

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Science China(Physics,Mechanics & Astronomy) 2012年第6期55卷 1118-1124页

作者： WANG XueWei yu yang Biomechanics and Biomaterials Laboratory Department of MechanicsSchool of Aerospace EngineeringBeijing Institute of TechnologyBeijing 100081China

In this study,a theoretical model was established for predicting the equilibrium shape of the droplet on flat and spherical *** theoretical equilibrium shape of heavy droplets could be obtained once contact angle and volume of droplets were *** showed that the predictions of the theoretical flat model were in good agreement with the shape obtained by Surface Evolver when the contact angle is below 120 and the droplet size is on the order of capillary *** available range will decrease and increase when the heavy droplet is on convex and concave spherical surface,respectively,in contrast to that on flat *** available range will decrease more for higher curvature of convex spherical surfaces.

关键词： equilibrium shape heavy droplet ellipsoidal model Surface Evolver simulation

单一及多组分混合物绿松石仿制品的光谱学特征研究

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光谱学与光谱分析 2025年第1期45卷 183-190页

作者：杨池玉汪田田张维肖汤维茜同济大学浙江学院浙江嘉兴314051

对市场新出现的一类仿制品进行了拉曼光谱、红外光谱、化学成分、紫外-可见-近红外吸收光谱分析,对其主要谱学特征进行了归纳总结。结果表明这类仿制品主要由重晶石、三水铝石、方解石粉末单一组分或多组分混合压制再经环氧树脂类或丙... 详细信息

对市场新出现的一类仿制品进行了拉曼光谱、红外光谱、化学成分、紫外-可见-近红外吸收光谱分析,对其主要谱学特征进行了归纳总结。结果表明这类仿制品主要由重晶石、三水铝石、方解石粉末单一组分或多组分混合压制再经环氧树脂类或丙烯酸酯类有机物胶结,并经人工染剂染色而成。红外光谱显示:单一矿物组分仿制品和绿松石差异明显,重晶石仿制品显示[SO_(4)]^(2-)的1078 cm^(-1)吸收峰等,方解石仿制品显示[CO_(3)]^(2-)的1476±cm^(-1)吸收峰等;多组分仿制品可见综合了多种矿物特征的吸收光谱,谱学特征复杂。根据缺失水峰,或仅显示三水铝石结构水OH-导致的3623、3528、3472和3388 cm^(-1)吸收峰,指纹区显示[SO_(4)]^(2-)、[CO_(3)]^(2-)相关吸收峰,可初步区分于绿松石。显微拉曼光谱测试结果表明多组分仿制品的不同测试位置矿物组成不同,可分别测试到三水铝石(3360、3432、3522、3614 cm^(-1))、重晶石(989 cm^(-1))、方解石(1088 cm^(-1))的特征峰,结合显微拉曼光谱及化学分析结果可进一步确认仿制品的具体矿物组成。紫外-可见-近红外吸收光谱表明样品均经人工染剂染色,显示633±、713±nm吸收宽峰或610±、675±nm吸收宽峰。

关键词：三水铝石重晶石方解石振动光谱微区分析