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基于改进GAN的闸门结构数据增强研究

水电能源科学 2025年第1期43卷 103-107页

作者：黄建章张钰奇铁瑛徐平郑州大学机械与动力工程学院河南郑州450001 郑州大学水利与交通学院河南郑州450001

为保证大坝闸门的正常运行,需在闸门上布置大量传感器进行健康监测。然而在实际运行中,由于闸门所处的工作环境恶劣,经常造成传感器所采集数据发生缺失,导致采集的数据样本不充足,不具有代表性。对此,基于传统的生成对抗网络(GAN)算法,... 详细信息

为保证大坝闸门的正常运行,需在闸门上布置大量传感器进行健康监测。然而在实际运行中,由于闸门所处的工作环境恶劣,经常造成传感器所采集数据发生缺失,导致采集的数据样本不充足,不具有代表性。对此,基于传统的生成对抗网络(GAN)算法,提出了Attention-GAN算法对原始数据进行扩充。试验结果表明,Attention-GAN算法生成样本与原始样本之间的相似性比传统的GAN算法得到了明显提高,其中平均余弦相似度在闸门数据集上相较于GAN提高了9.87%。可见该算法能够有效地实现小样本露顶式闸门加速度数据增强。

关键词： Attention-GAN 数据增强结构数据 VMD去噪

Level set method for numerical simulation of a cavitation bubble,its growth, collapse and rebound near a rigid wall

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Acta Mechanica Sinica 2007年第6期23卷 645-653页

作者： Juntao huang Huisheng zhang Department of Mechanics and Engineering Sciences Fudan University Shanghai 200433 China

A level set method of non-uniform grids is used to simulate the whole evolution of a cavitation bubble, including its growth, collapse and rebound near a rigid wall. Single-phase Navier-Stokes equation in the liquid region is solved by MAC projection algorithm combined with second-order ENO scheme for the advection terms. The moving inter-face is captured by the level set function, and the interface velocity is resolved by ＂one-side＂ velocity extension from the liquid region to the bubble region, complementing the second-order weighted least squares method across the interface and projection inside bubble. The use of non-uniform grid overcomes the difficulty caused by the large computational domain and very small bubble size. The computation is very stable without suffering from large flow-field gradients, and the results are in good agreements with other studies. The bubble interface kinematics, dynamics and its effect on the wall are highlighted, which shows that the code can effectively capture the ＂shock wave＂-like pressure and velocity at jet impact, toroidal bubble, and complicated pressure structure with peak, plateau and valley in the later stage of bubble oscillating.

关键词： Level set method Cavitation bubble Collapsing and rebounding Jet impact Toroidal bubble

The three-dimension model for the rock-breaking mechanism of disc cutter andanalysis of rock-breaking forces

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Acta Mechanica Sinica 2012年第3期28卷 675-682页

作者： Zhao-huang zhang Fei Sun School of Energy Power and Mechanical EngineeringNorth China Electric Power University102206 BeijingChina School of Foreign Languages North China Electric Power University102206 BeijingChina

To study the rock deformation with three- dimensional model under rolling forces of disc cutter, by car- rying out the circular-grooving test with disc cutter rolling around on the rock, the rock mechanical behavior under rolling disc cutter is studied, the mechanical model of disc cutter rolling around the groove is established, and the the- ory of single-point and double-angle variables is proposed. Based on this theory, the physics equations and geometric equations of rock mechanical behavior under disc cutters of tunnel boring machine （TBM） are studied, and then the bal- ance equations of interactive forces between disc cutter and rock are established. Accordingly, formulas about normal force, rolling force and side force of a disc cutter are de- rived, and their validity is studied by tests. Therefore, a new method and theory is proposed to study rock- breaking mech- anism of disc cutters.

关键词： Full face rock tunnel boring machine (TBM) Disc cutte Three-dimension model

Effects of bacteria on nitrogen and phosphorus release from river sediment

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Journal of Environmental Sciences 2008年第4期20卷 404-412页

作者： WU Qunhe zhang Renduo huang Shan zhang Hengjun School of Environmental Science and Engineering Sun Yat-Sen （Zhongshan） University Guangzhou 510275 China

To better understand the mechanisms of eutrophication, we addressed the microbial processes that influence many key aspects of water-sediment systems. In this study, a large column experiment was conducted for 30 d. Along the column, solution samples were collected at different locations at different time. The samples were analyzed for physical, chemical, and biological properties of the sediment and overlying water. The results showed that the amount of nitrogen transforming bacteria was higher than that of phosphorous bacteria. The amount of nitrogen transforming bacteria was in the order： ammonifier 〉 denitrifying bacteria 〉 nitrobacteria and nitrosomonas. Principal component analysis indicated that the three main factors accounted for more than 90% overall contributions for bacterium growth, which represented nutrition, organics and oxygen, and pH and redox potential （Eh） of the environment. Corresponding to the bacteria, the concentrations of nitrogen in the system was in the order： ammonia （NH4＋-N）〉 nitrate （NO3^--N）〉 nitrite （NO2^--N）. The fluxes of N and P clearly showed a temporal release and adsorption processes in the water-sediment system. The large magnitude of N fluxes suggested that N might act as an important contamination source for the water quality. However, P exchange between the sediment and overlying water was less intensive during the experiment.

关键词： eutrophication sediment P and N transforming bacteria

Effect of trace tungsten on the microstructure of TiAl alloys containing Nb and B

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Rare Metals 2007年第4期26卷 323-329页

作者： LIU Bin LIU Yong huang Lan huang Jinsong zhang Yonghong huang Boyun State Key Laboratory of Powder Metallurgy Central South University Changsha 410083 China

New TiAl alloys, containing 45 at.% A1, 7 at.% Nb, x at.% W, and 0.15 at.% B （x = 0, 0.2, 0.4, and 0.7） were prepared by arc melting and drop casting consequently. Using optical microscopy, scanning electron microscopy （SEM）, and electron superprobe technologies, the effects of tungsten on the microstructural evolution of the TiA1 alloys, including the colony size and lamellar spacing, were analyzed. It was found that cellular structures and dendrites were formed in the as-cast TiA1 alloys, and heavy metals, such as niobium and tungsten, tend to segregate strongly at the interface of the cellular structures and dendrites. Trace tungsten can effectively impede the grain growth and narrow the interlamellar spacing. 0.4 at.% tungsten is more effective in refuting the microstructure of the TiAI alloys.

关键词： TiAl alloys tungsten grain size β(B2)phase microstructure

Laser stealth absorbent of samarium oxysulfide prepared by flux method

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Rare Metals 2011年第6期30卷 616-620页

作者： HAN Pengde huang Xiaogu zhang Qitu College of Materials Science and Engineering Nanjing University of Technology Nanjing 210009 China

A novel 1064 tun laser stealth absorbent of SmzO2S was prepared by flux method. The effects of different calcining temperatures and fluxes on the reflective property of Sm2O2S were investigated. The phase composition, morphology, and reflectivity of the powders were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and ultraviolet-visible spectrophotometer （UVPC）. The results showed that pure phase of Sm202S could be obtained with Na2CO3 as flux above 950~C, and the reflectivity decreased with the calcination temperature increasing. Compared with other samarium compounds, the reflectivity at 1064 nm of Sm2O2S was the lowest. Different fluxes had great impact on the phase composition, particle morphology, and reflectivity of the products. In short, Sm2O2S was suitable as a kind of absorbent against 1064 nm laser.

关键词： laser stealth samarium oxysulfide flux reflectivity

The comparative analysis of rocks' resistance to forward-slanting disc cutters and traditionally installed disc cutters

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Acta Mechanica Sinica 2016年第4期32卷 690-695页

作者： Zhao-huang zhang Sun Fei Meng Liang School of Energy Power and Mechanical EngineeringNorth China Electric Power University School of Foreign Languages North China Electric Power University

At present, disc cutters of a full face rock tunnel boring machine are mostly mounted in the traditional way. Practical use in engineering projects reveals that this installation method not only heavily affects the operation life of disc cutters, but also increases the energy consumption of a full face rock tunnel boring machine. To straighten out this issue, therefore, a rock-breaking model is developed for disc cutters＇ movement after the research on the rock breaking of forward-slanting disc cutters. Equations of its displacement are established based on the analysis of velocity vector of a disc cutter＇s rock-breaking point. The functional relations then are brought forward between the displacement parameters of a rock-breaking point and its coordinate through the analysis of micro displacement of a rock-breaking point. Thus, the geometric equations of rock deformation are derived for the forward-slanting installation of disc cutters. With a linear relationship remaining between the acting force and its deformation either before or after the leap breaking, the constitutive relation of rock deformation can be expressed in the form of generalized Hooke law, hence the comparative analysis of the variation in the resistance of rock to the disc cutters mounted in the forward-slanting way with that in the traditional way. It is discovered that with the same penetration, strain of the rock in contact with forwardslanting disc cutters is apparently on the decline, in otherwords, the resistance of rock to disc cutters is reduced. Thus wear of disc cutters resulted from friction is lowered and energy consumption is correspondingly decreased. It will be useful for the development of installation and design theory of disc cutters, and significant for the breakthrough in the design of full face rock tunnel boring machine.

关键词： installed breaking installation rock apparently tunnel traditionally decline remaining brought

Rock deformation equations and application to the study on slantingly installed disc cutter

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Acta Mechanica Sinica 2014年第4期30卷 540-546页

作者： Zhao-huang zhang Liang Meng Fei Sun School of Energy Power and Mechanical EngineeringNorth China Electric Power University School of Foreign Languages North China Electric Power University

At present the mechanical model of the interac- tion between a disc cutter and rock mainly concerns indentation experiment, linear cutting experiment and tunnel boring machine （TBM） on-site data. This is not in line with the actual rock-breaking movement of the disc cutter and impedes to some extent the research on the rock-breaking mechanism, wear mechanism and design theory. Therefore, our study focuses on the interaction between the slantingly installed disc cutter and rock, developing a model in accordance with the actual rock-breaking movement. Displacement equations are established through an analysis of the velocity vector at the rock-breaking point of the disc cutter blade; the func- tional relationship between the displacement parameters at the rock-breaking point and its rectangular coordinates is established through an analysis of micro-displacement vectors at the rock-breaking point, thus leading to the geometric equations of rock deformation caused by the slantingly installed disc cutter. Considering the basically linear relationship between the cutting force of disc cutters and the rock deformation before and after the leap break of rock, we express the constitutive relations of rock deformation as generalized Hooke＇s law and analyze the effect of the slanting installa- tion angle of disc cutters on the rock-breaking force. This will, as we hope, make groundbreaking contributions to the development of the design theory and installation practice of TBM.

关键词： TBM Disc cutter· Geometric equation Slant-ingly installed Rock-breaking

Two-dimensional semiconductors with possible high room temperature mobility

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Nano Research 2014年第12期7卷 1731-1737页

作者： Wenxu zhang Zhishuo huang Wanli zhang Yanrong Li State Key Laboratory of Electronic Thin Films and Integrated Devices University of Electronic and Technology of China Chengdu610054 China.

We have calculated the longitudinal acoustic phonon limited electron mobility of 14 twvo-dimensional semiconductors with composition of MX2, where M （= Mo, W, Sn, Hf, Zr and Pt） is the transition metal, and X is S, Se and Te. We treated the scattering matrix by the deformation potential approximation. We found that out of 14 compounds, MoTe2, HfSe2 and ZrSe2 are promising regarding to their possible high mobility and finite band gap. The phonon limited mobility can be above 2,500 cm^2·V^-1·s^-1 at room temperature.

关键词： electron mobility acoustic phonon ab initio two-dimensional (2D)materials