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Stable attenuation-compensated reverse time migration and its application to land seismic data

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Petroleum Science 2023年第5期20卷 2784-2795页

作者： Xin-Ru Mu Qiang Mao Jian-ping huang Geosciences Department China University of Petroleum(East China)QingdaoShandong266580China Pilot National Laboratory for Marine Science and Technology(Qingdao) QingdaoShandong266000China

Intrinsic attenuation of the earth causes energy loss and phase distortion in seismic wave *** obtain high-resolution imaging results,these negative effects must be considered during reverse time migration(RTM).We can easily implement attenuation-compensated RTM using the constant Q viscoacoustic wave equation with decoupled amplitude attenuation and phase dispersion ***,the nonphysical amplitude-compensation process will inevitably amplify the high-frequency noise in the wavefield in an exponential form,causing the numerical simulation to become *** is due to the fact that the amplitude of the compensation grows exponentially with *** order to achieve stable attenuation-compensated RTM,we modify the analytic expression of the attenuation compensation extrapolation operator and make it only compensate for amplitude loss within the effective frequency *** on this modified analytic formula,we then derive an explicit time-space domain attenuation compensation extrapolation ***,the implementation procedure of stable attenuation-compensated RTM is *** addition to being simple to implement,the newly proposed attenuation-compensated extrapolation operator is superior to the conventional low-pass filter in suppressing random noise,which will further improve the imaging *** use two synthetic and one land seismic datasets to verify the stability and effectiveness of the proposed attenuationcompensated RTM in improving imaging resolution in viscous media.

关键词： Seismic attenuation Reverse time migration Stability strategy Pseudospectral method

Analysis on Dynamic Characteristics in Time Domain of Slider with Ultra Thin Spacing

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Chinese Journal of Mechanical Engineering 2012年第3期25卷 439-445页

作者： YAO Huaping huang ping CHEN Yangzhi ZHU Lixue School of Mechanical and Electrical Engineering Zhongkai University of Agriculture and EngineeringGuangzhou 510225China School of Mechanical and Automobile Engineering South China University of TechnologyGuangzhou 510640China

With increasing recording density in computer hard disks,the flying height of the magnetic head becomes 10 nm or *** numerical method of the control equations needs to be optimized consistently with the decrease of the flying *** iterative process is usually divergent with traditional methods which cannot ensure the accuracy of the analysis results and the stability of numerical ***,a new scheme is presented to solve the ultra-thin lubricating control equations in this *** equilibrium equation is obtained by taking the Couette flow terms and time term as dominating terms in iterative ***,the weighting flow factor is introduced for the abrupt change of film thickness in order to reduce calculated ***,the rules for variation of flying pose of the magnetic head with time are obtained by the time domain *** results show that the magnetic head can recover to the equilibrium position after being slightly influenced by outside *** the dynamic lubrication properties of the head suffer heavily from the vibrations in the height direction and fluctuation in the pitch ***,the analysis of the sine roughness-passing capacity of the head indicates that the head can surpass small sine waves and the equilibrium position can be retrieved after a period of decaying *** proposed research ensures the accuracy and stability of the numerical calculation of the control equations,and the dynamic characteristics and flying stability of a magnetic head is studied *** can also be the theoretical basis for the analysis of the flight characteristics of the slider.

关键词： dynamic characteristic ultra-thin spacing dynamic response magnetic head

General Model of Temperature-dependent Modulus and Yield Strength of Thermoplastic Polymers

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Chinese Journal of Polymer Science 2020年第4期38卷 382-393,I0007页

作者： ping-Yuan huang Zhan-Sheng Guo Jie-Min Feng Shanghai Institute of Applied Mathematics and Mechanics School of Mechanics and Engineering ScienceShanghai UniversityShanghai200072China Shanghai Key Laboratory of Mechanics in Energy Engineering Shanghai 200072China

A general model was developed to predict the temperature-dependent modulus and yield strength of different thermoplastic *** model,which depends on only two parameters with clear and specific physical meanings,can describe the temperaturedependent modulus and yield strength of thermoplastic polymers over the full glass transition *** temperature-dependent modulus and yield strength of three thermoplastic polymers were measured by uniaxial tension tests over a temperature range of 243-383 *** predictions showed excellent agreement with the experimental *** analysis of model input parameters showed negligible effect on the present general *** universality of the present general model was further validated,showing excellent agreement with published experimental data on other thermoplastic polymers and their composites.

关键词： Thermoplastics Modulus Yield strength Modeling Glass transition

Efficacy of granulocyte-colony stimulating factor treatment in a rat model of anterior ischemic optic neuropathy

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Neural Regeneration Research 2014年第16期9卷 1502-1505页

作者： Shun-ping huang Rong-Kung Tsai Department of Molecular Biology and Human Genetics Tzu Chi University Institute of Eye Research Buddhist Tzu Chi General Hospital Institute of Medical Sciences Tzu Chi University

Non-arteritic anterior ischemic optic neuropathy （NA-AION） is the most common cause of acute ischemic damage to the optic nerve （ON）, and the leading cause of seriously impaired vision in people over 55 years of age. It demonstrated that subcutaneous administration of Granulocyte colony-stimulating factor （G-CSF） reduces RGC death in an ON crush model in rats, and that the neuroprotective effects may involve both anti-apoptotic and anti-inflammatory processes. Our recent work shows that the protective actions of G-CSF in rAION models may involve both anti-apoptotic and anti-inflammatory processes. However, the exact rescuing mech- anisms involved in the administration of G-CSF in rAION models need further investigation. In addition, further studies on the administration of G-CSF at different time intervals after the induction of rAION may be able to illustrate whether treatment given at a later time is still neu- roprotective. Further, it is unknown whether treatment using G-CSF combined with other drugs will result in a synergistic effect in a rAION model. Inflammation induced by ischemia plays an essential role on the ON head in NA-A1ON, which can result in disc edema and compartment changes. Therefore, it is reasonable that adding an anti-inflammatory drug may enhance the therapeutic effects of G-CSF. An ongoing goal is to evaluate the novel sites of action of both G-CSF and other anti-inflammatory drugs, and to identify the functionally protective pathways to enhance RGC survival. These investigations may open up new therapeutic avenues for the treatment of ischemic optic neuropathy.

关键词： optic nerve anterior ischemic optic neuropathy retinal damage granulocyte colo-ny_stimulating factor inflammatory response

Spectral blueshift as a three-dimensional structure-ordering process

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Frontiers of physics 2017年第3期12卷 101-105页

作者： Jun-Ying huang Zu-Hui Wu Ji-ping huang Department of Physics State Key Laboratory of Surface Physics and Key Laboratory of Micro and Nano Photonic Structures (MOE) Fudan University Shanghai 200433 China Collaborative Innovation Center of Advanced Microstructures Nanjing 210093 China

The transmission spectra of a TiO2-silicone oil suspension in an increasing external electric field are studied. As the electric field increases, the structure of the suspension changes from a disordered one to an ordered one. Interestingly, the transmission spectra blueshift in this structure-ordering process. Furthermore, the relative transmission spectra exhibit Fano-like asymmetric line shapes. The deviation ratio of each asymmetric line shape increases monotonously as the disorder of the suspension decreases. We suggest that this blueshift phenomenon can be used to characterize the disorder strength of three- dimensional systems.

关键词： disordered medium light propagation transmission spectrum blueshift

Deconvolution Method for Determination of the Nitrogen Content in Cellulose Carbamates

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Chinese Chemical Letters 2001年第4期12卷 365-368页

作者： Guang Mei CHEN Yi ping huang Department of Chemistry Anhui UniversityHefei 230039

Cellulose carbamates (CC) were synthesized with microcrystalline cellulose as raw materials. The Fourier transform infrared spectra of CC with different nitrogen content were recorded. The accurate results of the nitrogen content for CC can be obtained by using the deconvolution method when the nitrogen content is less than 3.5%. The relationship between the nitrogen content and the absorption intensity ratio of the corresponding separated absorption peaks in FTIR spectra has been expressed bg an equation precisely.

关键词： Cellulose carbamates nitrogen content deconvolution method baseline method

Deep learning-based fault diagnostic network of high-speed train secondary suspension systems for immunity to track irregularities and wheel wear

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Railway Engineering Science 2022年第1期30卷 96-116页

作者： Yunguang Ye ping huang Yongxiang Zhang Institute of Land and Sea Transport Systems Technical University of BerlinBerlin 10587Germany National United Engineering Laboratory of Integrated and Intelligent Transportation Southwest Jiaotong UniversityChengdu 610031China Institute for Transport Planning and Systems ETH Zurich8093 ZurichSwitzerland

Fault detection and isolation of high-speed train suspension systems is of critical importance to guarantee train running safety. Firstly, the existing methods concerning fault detection or isolation of train suspension systems are briefly reviewed and divided into two categories, i.e., model-based and data-driven approaches. The advantages and disadvantages of these two categories of approaches are briefly summarized. Secondly, a 1D convolution network-based fault diagnostic method for highspeed train suspension systems is designed. To improve the robustness of the method, a Gaussian white noise strategy(GWN-strategy) for immunity to track irregularities and an edge sample training strategy(EST-strategy) for immunity to wheel wear are proposed. The whole network is called GWN-EST-1 DCNN method. Thirdly, to show the performance of this method, a multibody dynamics simulation model of a high-speed train is built to generate the lateral acceleration of a bogie frame corresponding to different track irregularities, wheel profiles, and secondary suspension faults. The simulated signals are then inputted into the diagnostic network, and the results show the correctness and superiority of the GWN-EST-1DCNN method. Finally,the 1DCNN method is further validated using tracking data of a CRH3 train running on a high-speed railway line.

关键词： High-speed train suspension system Fault diagnosis Track irregularities Wheel wear Deep learning Literature review

Microsurgical vasoepididymostomy for patients withinfectious obstructive azoospermia, cause, outcome,and associated factors

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Asian Journal of Andrology 2016年第5期18卷 759-762页

作者： Xiang-Feng Chen Bin Chen Wei Liu Yan-ping huang Hong-Xiang Wang Yi-Ran huang ping ping Center for Reproductive Medicine Shanghai Human Sperm Bank Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200135 China Department of Urology Shanghai Institute of Andrology Ren Ji Hospital School of Medicine Shanghai Jiao Tong University Shanghai 200127 China Shanghai KeyLaboratory for Assisted Reproduction and Reproductive Genetics Shanghai 200135 China.

Azoospermia is of great importance to male infertility. Obstructive azoospermia （OA） due to infection is the most prevalent form of OA in China and has been less studied. We aim to observe the treatment outcome of microsurgical vasoepididymostomy （VE） and also to identify the factors relative to the result after reconstructive surgery. Two hundred and eight men presenting with OA due to infection during the study period from July 2010 to July 2013 were prospectively evaluated. Clinical examination, semen analysis, serum follicle stimulating hormone （FSH）, and scrotal ultrasound were done before surgical exploration. Among the 198 men who were selected for surgical procedures, 159 candidates underwent microsurgical VE with sperm detected in the epididymal fluid. As for the other 39 cases, reconstruction was not feasible. The average age was 28.5 ＋ 3.9 years （range 22-38）, with average follow-up being 16.5 ~ 5.9 months （range 4-28）. According to the 150 cases being followed after VE procedures, the total patency rate was 72% （108/150）. During follow-up, 38.7% （58/150） natural pregnancies occurred, with overall live birth rate being 32.7% （49/150）. Our data suggested that microsurgical VE is an effective therapy for postinfectious epididymal OA. Individualized counseling with prognosis based on etiology should be offered to patients to select optical therapy.

关键词： infection obstructive azoospermia vasoepididymostomy

Progress in physical properties of Chinese stock markets

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Frontiers of physics 2013年第4期8卷 438-450页

作者： Yuan Liang Guang Yang Ji-ping huang Department of Physics and State Key Laboratory of Surface Physics Fudan University Shanghai 200433 China Department of Applied Physics College of Science Donghua University Shanghai 201620 China

In the past two decades, statistical physics was brought into the field of finance, applying new methods and concepts to financial time series and developing a new interdiscipline ＂econophysics＂. In this review, we introduce several commonly used methods for stock time series in econophysics including distribution functions, correlation functions, detrended fluctuation analysis method, de- trended moving average method, and multifractal analysis. Then based on these methods, we review some statistical properties of Chinese stock markets including scaling behavior, long-term correla- tions, cross-correlations, leverage effects, antileverage effects, and multifractality. Last, based on an agent-based model, we develop a new option pricing model -- financial market model that shows a good agreement with the prices using real Shanghai Index data. This review is helpful for people to understand and research statistical physics of financial markets.

关键词： econophysics Chinese stock market statistical method statistical physics

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