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Design,hydrodynamic analysis,and testing of a bioinspired controllable wing mechanism with multi-locomotion modes for hybrid-driven underwater gliders

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Science China(Technological Sciences) 2021年第12期64卷 2688-2708页

作者： SUN TongShuai wang yanhui YANG ShaoQiong wang Cheng ZHANG LianHong Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin 300072China Qingdao Pilot National Laboratory for Marine Science and Technology(QNLM) Qingdao 266237China

Hybrid-driven technology,which can improve the sailing performance of underwater gliders(UGs),has been successfully used in ocean ***,a hybrid-driven UG(HUG)with an added tail propeller is still unable to achieve backward and turning motion with a body length radius,and the hydrodynamic pitch moment acting on the HUG that is mainly caused by the fixed-wing makes it difficult to achieve high-precision attitude control during fixed-depth *** solve this problem,a two-degree-of-freedom bioinspired controllable wing mechanism(CWM)is proposed to improve the maneuverability and cruising ability of *** CWM can realize five motion modes:modifying the dihedral angle or anhedral angle,changing the frontal area of the wing,switching the wing from horizontal to be a vertical rudder,flapping the wing as propulsion,and rotating the wing as a vector ***,the design process of the CWM is provided,and hydrodynamic forces in each motion mode of three CWMs with different trailing edge sweepback angles(TESA)and attitude angles are analyzed through computational fluid dynamics *** relationship between hydrodynamics and the attitude angles or TESA of the CWM is ***,experiments are conducted to measure the hydrodynamics of the CWM when it is in a flapping wing mode and rotating the wing as a vector propeller,*** hydrodynamic forces obtained from the simulation are consistent with data measured by a force sensor,proving the credibility of the simulated ***,by applying the results of the hydrodynamic force in this study,the flapping trajectory of the wingtip is planned using the cubic spline interpolation ***,two underwater demo vehicles with a pair of CWMs are developed,and experiments are conducted in a water tank,further validating and demonstrating the feasibility of the proposed CWM.

关键词： controllable wing mechanism hybrid-driven underwater glider bioinspired design multi-locomotion modes

An improved probabilistic relaxation method for matching multi-scale road networks

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International Journal of Digital Earth 2018年第6期11卷 635-655页

作者： Jianchen Zhang yanhui wang Wenji Zhao College of Resources Environment and Tourism Capital Normal UniversityBeijingPeople’s Republic of China D Information Collection and Application Key Lab of Education Ministry Capital Normal UniversityBeijingPeople’s Republic of China Beijing State key Laboratory Incubation Base of Urban Environmental Processes and Digital Simulation Capital Normal UniversityBeijingPeople’s Republic of China

Matching multi-scale road networks in the same area is the first step in merging two road networks or updating one based upon the *** quality of the merge or update depends greatly on the matching accuracy of the two road *** propose an improved probabilistic relaxation method,considering both local and global optimizations for matching multi-scale of road *** aim is to achieve local optimization,as well as to address the identification of the M:N matching pattern by means of inserting virtual nodes to achieve global optimization ***,by adding two attribute-related evaluation indicators,we developed four evaluation indicators to evaluate the matching accuracy,considering both geographic and attribute *** paper also provides instructions on how to identify the proper buffer threshold during matching *** experiments were conducted to compare the proposed method with the traditional *** results indicate that:(1)the overall matching accuracy of each evaluation indicator exceeds 90%;(2)the overall matching accuracy increases by 6–12%after an M:N matching pattern is added,and by 4–6%following the addition of topology indicators;and(3)the proper buffer threshold is about twice the average value of the closest distance from all nodes.

关键词： Improved probabilistic relaxation multi-scale road network matching topology constraint M:N matching pairs matching accuracy

Period Multiplication in a Continuous Time Series of Radio-Frequency DBDs at Atmospheric Pressure

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Communications in Computational Physics 2012年第4期11卷 1226-1235页

作者： Jiao Zhang yanhui wang Dezhen wang State Key Laboratory of Materials Modification by Laser Electronand Ion BeamsSchool of Physics and Optoelectronic TechnologyDalian University of TechnologyDalian 116024China

As a spatially extended dissipative system with strong nonlinearity,the radio-frequency(rf)dielectric-barrier discharges(DBDs)at atmospheric pressure possess complex spatiotemporal nonlinear *** this paper,the time-domain nonlinear behaviors of rf DBD in atmospheric argon are studied numerically by a onedimensional fluid *** results show that,under appropriate controlling parameters,the rf DBD can undergo a transition from single-period state to chaos through period doubling bifurcation with increasing discharge time,i.e.,the regular periodic oscillation and chaos can coexist in a long time series of the atmosphericpressure rf *** increasing applied voltage amplitude,the duration of the periodic oscillation reduces gradually and chaotic zone increases,and finally the whole discharge series becomes completely chaotic *** is different from conventional period doubling route to ***,the spatial characteristics of rf perioddoubling discharge and chaos,as well as the parameter range of various discharge behaviors occurring are also investigated in this paper.

关键词： Atmospheric radio-frequency discharge period-doubling bifurcation chaos

Design,Hydrodynamic Analysis,and Testing of a Bio-inspired Movable Bow Mechanism for the Hybrid-driven Underwater Glider

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Journal of Bionic Engineering 2023年第4期20卷 1493-1513页

作者： yanhui wang Yudong Guo Shaoqiong Yang Tongshuai Sun Xi wang Huihui Zhou Key Laboratory of Mechanism Theory and Equipment Design of Ministry of Education Tianjin UniversityTianjin300072China The Joint Laboratory of Ocean Observing and Detection Laoshan LaboratoryQingdao266237China

Hybrid-driven Underwater Glider(HUG)is a new type of underwater vehicle which integrates the functions of an Autonomous Underwater Glider(AUG)and an Autonomous Unmanned Vehicle(AUV).Although HUG has the characteristics of long endurance distance,its maneuverability still has room to be *** work introduces a new movement form of the neck of the underwater creature into HUG and proposes a parallel mechanism to adjust the attitude angle and displacement of the HUG’s bow,which can improve the steering ***,the influence of bow movement and rotation on the hydrodynamic force and flow field of the whole machine is analyzed by using the Computational Fluid Dynamics(CFD)*** degree of freedom,attitude control range and movement amount of the Movable Bow Mechanism(MBM)are obtained,and then the design of MBM is completed based on these ***,the kinematic and dynamic models of MBM are established based on the closed vector method and the Lagrange equation,respectively,which are fully verified by comparing the results of simulation in Matlab and Adams software,then a Radial Basis Function(RBF)neural network adaptive sliding mode controller is designed to improve the dynamic response effect of the output parameters of ***,a prototype of MBM is manufactured and *** kinematic,dynamics model and controller are verified by experiments,which provides a basis for applying MBM in HUGs.

关键词： Underwater glider Movable bow mechanism Hydrodynamic simulation Steering maneuverability

Effect of Coiling Temperature on the Evolution of Texture in Ferritic Rolled Ti-IF Steel

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Journal of Materials Science & Technology 2007年第3期23卷 337-341页

作者： Zhaodong wang yanhui CUO Wenying XUE Xianghua LIU Cuodong wang The State Key Laboratory of Rolling and Automation Northeastern University Shenyang 110004 China

The effect of coiling temperatures on the evolution of texture in Ti-IF steel during ferritic hot rolling, cold rolling and annealing was studied. It was found that texture evolution at high temperature coiling is absolutely different from that at low temperature one. The hot band texture includes a strong α-fiber as well as a weak γ-fiber after ferritic hot rolling and low temperature coiling. Both of them intensify after cold rolling and a γ-fiber with peak at {111}〈112〉 is the main texture of annealed samples. However, the main component of the hot band texture after high temperature coiling is v-fiber. After cold rolling, the intensity of γ texture reduces; α fiber （except {111}〈110〉 component） intensifies and a strong and well-proportioned γ-fiber forms in the annealed samples.

关键词： Ti-IF steel Ferritic hot rolling Coiling temperature Texture

FGM-SPCL:Open-Set Recognition Network for Medical Images Based on Fine-Grained Data Mixture and Spatial Position Constraint Loss

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Chinese Journal of Electronics 2024年第4期33卷 1023-1033页

作者： Ruru ZHANG Haihong E Lifei YUAN yanhui wang Lifei wang Meina SONG School of Computer Science Beijing University of Posts and Telecommunications Engineering Research Center of Information Networks Ministry of Education Hebei Eye Hospital

The current intelligent auxiliary diagnosis models all follow the closed-set recognition setting. After the model is deployed online, the input data is often not completely controlled. Diagnosing an untrained disease as a known category would lead to serious medical malpractice. Therefore, realizing the open-set recognition is significant to the safe operation of the intelligent auxiliary diagnosis model. Currently, most open-set recognition models are studied for natural images, and it is very challenging to obtain clear and concise decision boundaries between known and unknown classes when applied to fine-grained medical images. We propose an open-set recognition network for medical images based on fine-grained data mixture and spatial position constraint loss(FGM-SPCL) in this *** the fine graininess of medical images and the diversity of unknown samples, we propose a fine-grained data mixture(FGM) method to simulate unknown data by performing a mixing operation on known data to expand the coverage of unknown data difficulty levels. In order to obtain a concise and clear decision boundary, we propose a spatial position constraint loss(SPCL) to control the position distribution of prototypes and samples in the feature space and maximize the distance between known classes and unknown classes. We validate on a private ophthalmic OCT dataset, and extensive experiments and analyses demonstrate that FGM-SPCL outperforms state-of-the-art models.

关键词： Analytical models Fine-grained image recognition Prototypes Aerospace electronics Spatial databases Robustness Data models

Modelling the response of larch growth to age,density,and elevation and the implications for multifunctional management in northwest China

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Journal of Forestry Research 2023年第5期34卷 1423-1436页

作者： Ao Tian yanhui wang Ashley A.Webb Pengtao Yu Xiao wang Zebin Liu Institute of Mountain Resource of Guizhou Province Guiyang 550001People’s Republic of China Ecology and Nature Conservation Institute Key Laboratory of Forest Ecology and Environment of National Forestry and Grassland AdministrationChinese Academy of ForestryBeijing 100091People’s Republic of China WaterNSW TamworthNSWAustralia

Plantations of Rupprecht's larch(Larix principis-rupprechtii)have been widely established in the drylands of northwest and north China under traditional fastgrowing plantation management *** strategies and the long-term logging ban have led to over-populated stands with lower structural and functional stability,less economic benefit and higher water *** guide the sustainable management of larch plantations,field surveys and historical data compilation were undertaken in the Liupan Mountains of northwest *** main influencing factors(stand structure and site condition)and their effects on mean tree height,mean DBH and timber volumes were determined based on up-boundary line *** growth models coupling the effects of tree age,stand density,and elevation were *** height and DBH markedly increased initially and then slowly with tree age,decreased with stand density,and showed unimodal change with *** coupled growth models accounted for72-78%of the variations in tree height,DBH and timber *** for future plantation management are:(1)prolong the rotation to at least 60 years to produce large-diameter,high-quality timber and maintain greater carbon stocks;(2)zone the target functions of stands by elevation;and,(3)reduce stand density for balanced supply of multiple ecosystem *** growth models developed can predict growth response of larch plantations to density alteration under given ages and elevations,and assist the transformation from traditional management for maximum timber production to site-specific and multifunctional management with longer rotations and moderate tree density.

关键词： Larch plantations Coupled growth model Influencing factors Age Density Elevation

U-Concordant Semigroups

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Algebra Colloquium 2018年第2期25卷 295-318页

作者： Xueming Ren yanhui wang K.P. Shum Department of Mathematics Xi'an University of Architecture and Technology Xi'an 710055 China College of Mathematics and Systems Science Shandong University of Science and Technology Qingdao Shandong 266590 China Institute of Mathematics Yunnan University Kunming 650091 China

We introduce the relations Lu and Ru with respect to a subset U of idempotents. Based on Lv and Rv, we define a new class of semigroups which we name U-concordant semigroups. Our purpose is to describe U-concordant semigroups by generalized categories over a regular biordered set. We show that the category of U-concordant semigroups and admissible morphisms is isomorphic to the category of RBS generalized categories and pseudo functors. Our approach is inspired from Armstrong＇s work on the connection between regular biordered sets and concordant semigroups. The significant difference in strategy is by using RBS generalized categories equipped with pre-orders, we have no need to discuss the quotient of a category factored by a congruence.

关键词： regular semigroup regular biordered set RBS generalized category RBS generalized groupoid concordant semigroup

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喹啉酮衍生物的生物活性与荧光性能研究进展

化学与生物工程 2025年第2期42卷 9-15,23页

作者：王静张亚峰王艳慧金丹刘思彤孙东明中钢集团鞍山热能研究院有限公司煤焦油系新型材料制备技术国家地方联合研究工程中心辽宁鞍山114044

喹啉酮衍生物是天然产物结构基序和多种药物结构骨架的重要组成部分,具有高荧光量子产率和高稳定性的荧光性能。综述了喹啉酮衍生物的生物活性与荧光性能研究进展,为喹啉酮衍生物在药理学活性与荧光探针方面的研究提供了借鉴和参考。

关键词：喹啉酮生物活性荧光性能