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水陆两栖飞机设计中的结构优化与材料选择研究

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价值工程 2025年第1期44卷 50-52页

作者：谢福熹温盛宏广西城市职业大学崇左532200

水陆两栖飞机的设计是一项复杂的工程挑战,涉及机身、机翼、机尾和着水装置的结构优化,以及材料选择和轻量化设计。机身设计需考虑整体结构布局、水上起降能力和结构强度与重量的平衡。机翼设计关注形状、气动性能和水上操作性能。机尾... 详细信息

水陆两栖飞机的设计是一项复杂的工程挑战,涉及机身、机翼、机尾和着水装置的结构优化,以及材料选择和轻量化设计。机身设计需考虑整体结构布局、水上起降能力和结构强度与重量的平衡。机翼设计关注形状、气动性能和水上操作性能。机尾设计则侧重于尾翼布局和稳定性。着水设计包括着水装置和冲击力吸收。材料选择方面,需考虑结构材料、防腐性能、轻量化设计以及成本与可靠性。这些设计要素共同确保了水陆两栖飞机的高效性能和安全性。

关键词：水陆两栖飞机结构优化材料选择

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Fe^(3+)-stabilized Ti_(3)C_(2)T_(x) MXene enables ultrastable Li-ion storage at low temperature

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Journal of Materials Science & Technology 2021年第8期67卷 156-164页

作者： Nana Zhao Fengchu zhang Fei zhan Ding Yi Yijun Yang Weibin Cui xi Wang Key Laboratory of Electromagnetic Processing of Materials Ministry of EducationDepartment of Physics and Chemistry of MaterialsSchool of Materials Science and EngineeringNortheastern UniversityShenyang 110819China Key Laboratory of Luminescence and Optical Information Ministry of EducationSchool of ScienceBeijingjiaotong UniversityBeijing 100044China Chemistry and Chemical Engineering Guangdong Laboratory Shantou 515031China

It is highly important to develop ultrastable electrode materials for Li-ion batteries(LIBs),especially in the low ***,we report Fe^(3+)-stabilized Ti_(3)C_(2)T_(x) MXene(donated as T/F-4:1)as the anode material,which exhibits an ultrastable low-temperature Li-ion storage property(135.2 m A h g^(-1)after300 cycles under the current density of 200 m A g^(-1)at-10℃),compared with the negligible capacity for the pure Ti_(3)C_(2)T_(x) MXene(26 m A h g^(-1)at 200 m A g^(-1)).We characterized as-made T/F samples via the Xray photoelectron spectroscopy(XPS),Fourier transformed infrared(FT-IR)and Raman spectroscopy,and found that the terminated functional groups(-O and-OH)in T/F are Li^(+) storage ***^(3+)-stabilization makes-O/-OH groups in MXene interlayers become active towards Li^(+),leading to much more active sites and thus an enhanced capacity and well cyclic *** contrast,only-O/-OH groups on the top and bottom surfaces of pure Ti_(3)C_(2)T_(x) MXene can be used to adsorb Li^(+),resulting in a low *** electron microscopy(TEM)and XPS data confirm that T/F-4:1 holds the highly stable solid electrolyte interphase(SEI)layer during the cycling at-10℃.Density functional theory(DFT)calculations further uncover that T/F has fast diffusion of Li^(+) and consequent better electrochemical performances than pure Ti_(3)C_(2)T_(x) *** is believed that the new strategy used here will help to fabricate advanced MXene-based electrode materials in the energy storage application.

关键词： Ti_(3)C_(2)T_(x)MXene Li-ion storage Low temperature Solid electrolyte interphase Density functional theory

TURBULENT OPEN CHANNEL FLOW SUBJECTED TO THE CONTROL OF A SPANWISE TRAVELING WAVE

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Journal of Hydrodynamics 2009年第1期21卷 65-70页

作者： LIU Nan-sheng WANG Lei LU xi-yun Department of Modem Mechanics University of Science and Technology of China Hefei 230026 China

Turbulent open channel flows subjected to the control of a spanwise traveling wave have been investigated by means of Direct Numerical Simulation （DNS）. The objective of this study is to reveal the response of the near-wall and surface-influenced turbulence to the spanwise traveling wave control. Three typical frequencies of the spanwise traveling wave, i.e., high-, middle- and low-frequency, corresponding to the exciting periods at 25, 50 and 100, are considered to study the turbulence dynamics in the wall and surface regions. To elucidate the behaviors of turbulence statistics, some typical quantities, including the mean velocity, velocity fluctuations and the structures of turbulence fluctuations, are exhibited and analyzed.

关键词： turbulent open channel flow traveling wave Direct Numerical Simulation (DNS) turbulence statistics turbulence structures

Contour detection in Cassini ISS images based on Hierarchical Extreme Learning Machine and Dense Conditional Random Field

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Research in Astronomy and Astrophysics 2020年第1期20卷 83-92页

作者： xi-Qi Yang Qing-Feng zhang zhan Li Department of Computer Science Jinan UniversityGuangzhou 510632China State Key Lab of CAD&CG Zhejiang UniversityHangzhou 310000China Sino-French Joint Laboratory for Astrometry Dynamics and Space ScienceJinan UniversityGuangzhou 510632China

In Cassini ISS(Imaging Science Subsystem)images,contour detection is often performed on disk-resolved objects to accurately locate their ***,contour detection is a key *** edge detection methods,such as Canny and Roberts,often extract the contour with too much interior details and *** the deep convolutional neural network has been applied successfully in many image tasks,such as classification and object detection,it needs more time and computer *** this paper,a contour detection algorithm based on H-ELM(Hierarchical Extreme Learning Machine)and Dense CRF(Dense Conditional Random Field)is proposed for Cassini ISS *** experimental results show that this algorithm’s performance is better than both traditional machine learning methods,such as Support Vector Machine,Extreme Learning Machine and even deep Convolutional Neural *** extracted contour is closer to the actual ***,it can be trained and tested quickly on the general configuration of PC,and thus can be applied to contour detection for Cassini ISS images.

关键词： techniques:image processing methods:data analysis astrometry

Changes of tear film and tear secretion after phacoemulsification in diabetic patients

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2008年第4期9卷 324-328页

作者： xi LIU Yang-shun GU Ye-sheng XU Ophthalmology Center the First Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310003 China

Objective: To evaluate tear film stability and tear secretion in patients with diabetes after phacoemulsification. Methods: Twenty-five diabetic cataract patients and 20 age-matched non-diabetic cataract patients as control underwent pha- coemulsification. Tear film break-up time (TFBUT), Schirmer I test (SIT), corneal fluorescein staining, and dry eye symptoms were measured pre- and postoperatively. Results: Diabetics had a decreased preoperative TFBUT and SIT. TFBUT was reduced on Day 1 and recovered on Day 180 postoperatively in both groups. SIT was increased after phacoemulsification, but returned to preoperative levels by Day 180 in non-diabetics, whereas it was lower than preoperative level in diabetics. Positive corneal fluo- rescein staining was elevated in both groups, and returned to preoperative levels only in controls. Dry eye symptoms were similar to fluorescein staining in both groups. Conclusion: Tear secretion was reduced in diabetic cataract patients after phacoe- mulsification, which worsened dry eye symptoms and predisposed those patients to ocular damage.

关键词： Phacoemulsification Diabetes Cataract Tear

Influence of Pre-Transformed Martensite on Work-Hardening Behavior of SUS 304 Metastable Austenitic Stainless Steel

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Journal of Iron and Steel Research International 2010年第3期17卷 51-55页

作者： XUE Zong-yu ZHOU sheng WEI xi-cheng School of Materials Science and Engineering Shanghai University Shanghai 200072 China

The metastable austenite was transformed to martensite by prestrain tension of SUS304 stainless steel to study the influence of transformed martensite on its subsequent work-hardening behavior under the uniaxial tensile condition. The X-ray diffractometer （XRD） was employed to detect the transformed martensite. Results showed that the volume fraction of transformed martensite increases with increasing prestrain. The pre-transformed martensite in the microstructure remarkably affects the deformation behavior of the steel, and the strength increases and the elongation decreases. The work-hardening curve of prestrained specimens observably changes with true strain. The work-hardening exponent n of stainless steel decreases with the increase of pre-transformed martensite. The achievement is a significant contribution to the process design during pressing.

关键词： prestrain SUS304 stainless steel martensite work-hardening behavior

Optimal power allocation for two-way relaying over OFDM using physical-layer network coding

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The Journal of China Universities of Posts and Telecommunications 2011年第1期18卷 9-15,35页

作者： LI Fu-nian ZHU Guang-xi WANG De-sheng Department of Electronic and Information Engineering Huazhong University of Science and Technology Wuhan 430074 China Department of Electronic and Information Engineering Wuhan University of Science and Technology Wuhan 430081 China

In this paper, a network scenario of two-way relaying over orthogonal frequency division multiplexing （OFDM） is considered, in which two nodes intend to exchange the information via a relay using physical-layer network coding （PLNC）. Assuming that the full channel knowledge is available, an optimization problem, which maximizes the achievable sum rate under a sum-power constraint, is investigated. It is shown that the optimization problem is non-convex, which is difficult to find the global optimum solution in terms of the computational complexity. In consequence, a low-complexity optimal power allocation scheme is proposed for practice implementation. A link capacity diagram is first employed for power allocation on each subcarrier. Subsequently, an equivalent relaxed optimization problem and Karush-Kuhn-Tucker （KKT） conditions are developed for power allocation among each subcarrier. Simulation results demonstrate that the substantial capacity gains are achieved by implementing the proposed schemes efficiently with a low-complexity computational effort.

关键词： two-way relaying power allocation physical-layer network coding OFDM

Iterative Learning Control for Discrete Parabolic Distributed Parameter Systems

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International Journal of Automation and computing 2015年第3期12卷 316-322页

作者： xi-sheng Dai Sen-Ping Tian Ya-Jun Guo College of Electrical Engineering and Automation Shandong University of Science and Technology School of Electrical and Information Engineering Guangxi University of Science and Technology School of Automation Science and Engineering South China University of Technology

In this paper, iterative learning control(ILC) technique is applied to a class of discrete parabolic distributed parameter systems described by partial difference equations. A P-type learning control law is established for the system. The ILC of discrete parabolic distributed parameter systems is more complex as 3D dynamics in the time, spatial and iterative domains are *** overcome this difficulty, discrete Green formula and analogues discrete Gronwall inequality as well as some other basic analytic techniques are utilized. With rigorous analysis, the proposed intelligent control scheme guarantees the convergence of the tracking error. A numerical example is given to illustrate the effectiveness of the proposed method.

关键词： Intelligent control iterative learning control discrete systems distributed parameter systems convergence analysis.

Well-Posedness and Structural Stability on a System of Simultaneous Generalized Vector Quasi-Equilibrium Problems

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Journal of the Operations Research Society of China 2021年第1期9卷 151-161页

作者： xi-Cai Deng Wen-sheng Jia Yan-Long Yang Department of Mathematics and Computer Guizhou Normal CollegeGuiyang 550018China Department of Mathematics Guizhou UniversityGuiyang 550025China

In this paper,we establish the stable results for a system of simultaneous general-ized vector quasi-equilibrium problems(SSGVQEP)by using its bounded rationality *** the abstract frame,a unified well-posedness on Hadamard types and Tikhonov types well-posedness for SSGVQEP is ***,sufficient condition for the well-posedness of SSGVQEP is ***,we prove that the majority(in Baire category sense)of SSGVQEP is structural stability.

关键词： Hadamard well-posedness Tikhonovwell-posedness Structural stability Bounded rationality