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Near-inertial waves in the wake of 2011 Typhoon Nesat in the northern South China Sea

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Acta Oceanologica Sinica 2014年第11期33卷 102-111页

作者： yang bing HOU Yijun Institute of Oceanology Chinese Academy of Sciences Key Laboratory of Chinese Academy of Sciences for Ocean Circulation and Waves Institute of Oceanology University of Chinese Academy of Sciences

In September 2011, Typhoon Nesat passed over a moored array of instruments recording current and temperature in the northern South China Sea（SCS）. A wake of baroclinic near-inertial waves（NIWs） commenced after Nesat passed the array. The associated near-inertial currents are surface-intensified and clockwise-polarized. The vertical range of NIWs reached 300 m, where the vertical range is defined as the maximum depth of the horizontal near-inertial velocity 5 cm/s. The current oscillations have a frequency of 0.709 9 cycles per day（cpd）, which is 0.025 f higher than the local inertial frequency. The NIWs have an e-folding time-scale of 10 d based on the evolution of the near-inertial kinetic energy. The depth-leading phase of near-inertial currents indicates downward group velocity and energy flux. The estimated vertical phase velocity and group velocity are 0.27 and 0.08 cm/s respectively, corresponding to a vertical wavelength of 329 m. A spectral analysis reveals that NIWs act as a crucial process to redistribute the energy injected by Typhoon Nesat. A normal mode and an empirical orthogonal function analysis indicate that the second mode has a dominant variance contribution of 81%, and the corresponding horizontal phase velocity and wavelength are 3.50 m/s and 420 km respectively. The remarkable large horizontal phase velocity is relevant to the rotation of the earth, and a quantitative analysis suggests that the phase velocity of the NIWs with a blue-shift of 0.025 f overwhelms that of internal gravity waves by a factor of 4.6.

关键词： near-inertial waves South China Sea Typhoon Nesat

Development of Laser-HVEM and Its Application on In-situ Observation on Lattice Defects Behavior

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Chinese Journal of Structural Chemistry 2020年第4期39卷 623-629页

作者： yang Zhan-bing yang Su-bing QU Xiao-Jian SHIBAYAMA Tamaki WATANABE Seiichi School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China Graduate School of Engineering Hokkaido UniversitySapporoHokkaido 060-8628Japan Centre for Advanced Research of Energy and Materials Faculty of EngineeringHokkaido UniversitySapporoHokkaido 060-8628Japan

A nanosecond pulse laser source head(Nd:YAG laser,Inlite Ⅱ-20,Continuum)was equipped to a high-voltage electron microscope(HVEM,Hitachi,H-1300)to develop a laser-HVEM system at Hokkaido *** the laser-HVEM,new methods for in-situ observation on the formation process of laser-induced lattice point defects at the internal of crystalline solid are achieved;some striking phenomena and potential mechanisms are *** the present paper,we review our progresses on in-situ experiments of lattice defects behavior in metal using the *** progresses are expected to provide insight for a broader application of laser-HVEM in scientific research.

关键词： Laser high-voltage electron microscope Dual-beam irradiation in-situ observation Lattice defect

Crack Growth Rate Model Derived from Domain Knowledge-Guided Symbolic Regression

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Chinese Journal of Mechanical Engineering 2023年第3期36卷 286-301页

作者： Shuwei Zhou bing yang Shoune Xiao Guangwu yang Tao Zhu State Key Laboratory of Traction Power Southwest Jiaotong UniversityChengdu 610031China

Machine learning(ML)has powerful nonlinear processing and multivariate learning capabilities,so it has been widely utilised in the fatigue ***,most ML methods are inexplicable black-box models that are difficult to apply in engineering *** regression(SR)is an interpretable machine learning method for determining the optimal fitting equation for *** this study,domain knowledge-guided SR was used to determine a new fatigue crack growth(FCG)rate *** terms of the variable subtree ofΔK,R-ratio,andΔK_(th)were obtained by analysing eight traditional semi-empirical FCG rate *** on the FCG rate test data from other literature,the SR model was constructed using *** was subsequently extended to other alloys(Ti-10V-2Fe-3Al,Ti-6Al-4V,Cr-Mo-V,LC9cs,Al-6013-T651,and Al-2324-T3)using multiple linear *** with the three semi-empirical FCG rate models,the SR model yielded higher prediction *** result demonstrates the potential of domain knowledge-guided SR for building the FCG rate model.

关键词： Fatigue crack growth rate Stress intensity factor range Threshold stress intensity factor range R-ratio Symbolic regression Machine learning

Remaining Useful Life for Heavy-Duty Railway Cast Steel Knuckles Based on Crack Growth Behavior with Hypothetical Distributions

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Chinese Journal of Mechanical Engineering 2024年第4期37卷 290-305页

作者： Chao Wang Tao Zhu bing yang Shoune Xiao Guangwu yang State Key Laboratory of Rail Transit Vehicle System Southwest Jiao tong UniversityChengdu 610031China

The current research on the integrity of critical structures of rail vehicles mainly focuses on the design stage,which needs an effective method for assessing the service *** paper proposes a framework for predicting the remaining useful life(RUL)of in-service structures with and without visible *** hypothetical distribution and delay time models were used to apply the equivalent crack growth life data of heavy-duty railway cast steel knuckles,which revealed the evolution characteristics of the crack length and life scores of the knuckle under different fracture failure *** results indicate that the method effectively predicts the RUL of service knuckles in different failure modes based on the cumulative failure probability curves for different locations and surface crack *** study proposes an RUL prediction framework that supports the dynamic overhaul and state maintenance of knuckle fatigue cracks.

关键词： Heavy-duty railway Cast steel knuckle Remaining useful life Fatigue crack growth Hypothetical distribution

Method for Evaluating Bolt Competitive Failure Life Under Composite Excitation

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Chinese Journal of Mechanical Engineering 2023年第4期36卷 372-384页

作者： Guangwu yang Long yang Han Zhao Haoxu Ding bing yang Shoune Xiao State Key Laboratory of Rail Transit Vehicle System Southwest Jiaotong UniversityChengdu 610031China

In this study,the competitive failure mechanism of bolt loosening and fatigue is elucidated via competitive failure tests on bolts under composite *** on the competitive failure mechanism,the mode prediction model and“load ratio-life prediction curve”(ξ-N curve)of the bolt competitive failure are *** the poor correlation of theξ-N curve,an evaluation model of the bolt competitive failure life is proposed based on Miner’s linear damage accumulation *** on the force analysis of the thread surface and simulation of the bolt connection under composite excitation,a theoretical equation of the bolt competitive failure life is established to validate the model for evaluating the bolt competitive failure *** results reveal that the proposed model can accurately predict the competitive failure life of bolts under composite excitation,and thereby,it can provide guidance to engineering applications.

关键词： Bolt Competitive failure life Evaluation model Mode prediction model Composite excitation

Power allocation of cooperative amplify-and-forward communications with multiple relays

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The Journal of China Universities of Posts and Telecommunications 2011年第4期18卷 65-69页

作者： WU Zhuo yang Hong-bing School of Communication and Information Engineering Shanghai University Shanghai 200072 China

Cooperative diversity is one of the most effective ways to mitigate the fading effect of wireless channels and obtain the spatial gain in wireless networks. In this paper, an optimal power allocation （OPA） scheme for a cooperative communication system using the amplify-and-forward （AF） transmit strategy with multiple relay users is proposed by minimizing the bit-error-rate （BER） at the destination under the constraint of the total transmit power of both the source user and the relay users. Simutation resutts indicate that the proposed power allocation method can achieve significant BER performance improvement than using the equal power allocation （EPA） scheme, while still attains low complexity. The system performance is improved significantly with the increasing of the number of relay users at high signal-noise ratio （SNR）. However, at low SNR, the system performance decreases when the relay number increases. Thus, an adaptive relay selection scheme may be used to choose the appropriate relay numbers in different transmission scenarios to provide system performance improvement and keep the power allocation scheme with low complexity.

关键词： cooperative communication AF EPA PA multiple relays BER

Genome editing in grass plants

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aBIOTECH 2020年第1期1卷 41-57页

作者： Si Nian Char bing yang Division of Plant Sciences University of MissouriColumbiaMO 65211USA Donald Danforth Plant Science Center St.LouisMO 63132USA

Cereal crops including maize,rice,wheat,sorghum,barley,millet,oats and rye are the major calorie sources in our daily life and also important bioenergy sources of the *** rapidly advancing and state-of-the-art genome-editing tools such as zinc finger nucleases,TAL effector nucleases,and clustered regularly interspaced short palindromic repeats(CRISPR)/CRISPR-associated systems(CRISPR-Cas9-,CRISPR-Cas12a-and CRISPR/Cas-derived base editors)have accelerated the functional genomics and have promising potential for precision breeding of grass *** the availability of annotated genomes of the major cereal crops,application of these established genome-editing toolkits to grass plants holds promise to increase the nutritional value and ***,these easy-to-use and robust genome-editing toolkits have advanced the reverse genetics for discovery of novel gene functions in crop *** this review,we document some of important progress in development and utilization of genome-editing tool sets in grass *** also highlight present and future uses of genome-editing toolkits that can sustain and improve the quality of cereal grain for food consumption.

关键词： Genome editing Cereal crops ZFNs TALENs CRISPR/Cas9 CRISPR/Cas12a Base editor

Design of Low-Power Modern Radar SoC Based on ASIX

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Tsinghua Science and Technology 2014年第2期19卷 168-173页

作者： bing yang Zongguang Yu Jinghe Wei Schoolol of Internetof Things Engineering Jiangnan University China Electronics Technology Group Corporation No.58 Research Institute

With the rapid development in spaceflights and aeroplanes, the demand for low-power and miniaturization techniques has become insistent in modern radar systems. A new framework for low-power modern radar System on a Chip （SoC） based on ASIX core is presented. Pivotal modules and low-power design flows are described in detail. The dynamic clock-distribution mechanism of the power management module and the influence of the chip power are both stressed. This design adopts the SMIC 0.18-μm 1P6M Salicide CMOS process, the area is 7.825 mm x 7.820 mm, there are approximately 2 million gates and the frequency is 100 MHz. The results show that the modern radar SoC passes the test on modern radar application system and meets the design requirements. The chip incurs power savings of 42.79% during the fore-end phase and 12.77% during the back-end phase. The total power is less than 350 mW for a 100-MHz operating environment.

关键词： ASIX core System on a Chip (SoC) low power system level circuit level logic level physical level modern radar

Novel Highly Selective Fluorescent Chemosensors for Hg（Ⅱ）

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Chemical Research in Chinese Universities 2013年第4期29卷 657-662页

作者： SU Wen-qi yang bing-qin Key Laboratory of Synthetic and Natural Functional Molecule Chemistry Ministry of Education Department of Chemistry Northwest University Xi'an 710069 P. R. China

Based on Rhodamine,two novel fluorescent Hg2＋ chemosensors（R1,R2） were synthesized from inexpensive starting *** were designed and synthesized with o-aminophenol and o-phenylenediamine derivatives as the Hg2＋ chelator,the comparison between the photophysical properties of two chemosensor molecules was *** chemosensors were designed with a photoinduced electron transfer（PET） *** binding to Hg2＋ which blocks the PET process,the fluorescence intensity of the chemosensors was enhanced by up to *** exhibit very strong fluorescence responses to Hg2＋ and have remarkably higher selectivity for Hg2＋ than for other metal ions including K＋,Na＋,Ca2＋,Mg2＋,Cd2＋,Mn2＋,Ni2＋,Co2＋,Zn2＋,Cu2＋,Cr3＋,Fe3＋,pb2＋,Ag＋,Al3＋,Fe2＋ and Sn2＋ in Tris-HC1/sodium phosphate *** fluorescence enhancement of R2 towards Hg2＋ maintains stable in wide pH span（6.4-8.8） aqueous solutions.

关键词： Fluorescent chemosensor Mercury ion Sensor Rhodamine fluorophore Fluorescence intensity