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New Optimization Design Method for a Double Secondary Linear Motor Based on R-DNN Modeling Method and MCS Optimization Algorithm

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Chinese Journal of Electrical Engineering 2020年第3期6卷 98-105页

作者： weitao wang Jiwen Zhao Yang Zhou Fei Dong School of Electrical Engineering and Automation Anhui UniversityHefei 230601China School of Electrical Engineering and Automation Hefei University of TechnologyHefei 230009China

Traditional linear motor optimization methods typically use analytical models combined with intelligent optimization ***,this approach has disadvantages,e.g.,the analytical model might not be accurate enough,and the intelligent optimization algorithm can easily fall into local optimization.A new linear motor optimization strategy combining an R-deep neural network(R-DNN)and modified cuckoo search(MCS)is proposed;additionally,the thrust lifting and thrust fluctuation reductions are regarded as optimization *** R-DNN is a deep neural network modeling method using the rectified linear unit(RELU)activation function,and the MCS provides a faster convergence speed and stronger data search capability as compared with genetic algorithms,particle swarm optimization,and standard CS ***,the validity and accuracy of this work are proven based on prototype experiments.

关键词： Double secondary linear motor(DSLM) machine learning modeling R-deep neural network(R-DNN)algorithm intelligent optimization algorithm modified cuckoo search(MCS)algorithm

Public cloud computing for seismological research:Calculating large-scale noise cross-correlations using ALIYUN

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Earthquake Science 2018年第5期31卷 227-233页

作者： weitao wang Baoshan wang Xiufen Zheng Key Laboratory of Seismic Observation and Geophysical Imaging Institute of GeophysicsChina Earthquake Administration School of Earth and Space Sciences University of Science and Technology of China

The amount of seismological data is rapidly increasing with accumulating observational time and increasing number of stations, requiring modern technique to provide adequate computing power. In present study, we proposed a framework to calculate large-scale noise crosscorrelation functions(NCFs) using public cloud service from ALIYUN. The entire computation is factorized into small pieces which are performed parallelly on specified number of virtual servers provided by the cloud. Using data from most seismic stations in China, five NCF databases are built. The results show that, comparing to the time cost using a single server, the entire time can be reduced over two orders of magnitude depending number of evoked virtual servers. This could reduce computation time from months to less than 12 hours. Based on obtained massive NCFs, the global body waves are retrieved through array interferometry and agree well with those from earthquakes. This leads to a solution to process massive seismic dataset within an affordable time and is applicable to other large-scale computing in seismological researches.

关键词： cloud computing ambient noise cross-correlation global body wave

Composition of high frequency ambient noise from cross-correlation:A case study using a small aperture array

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Earthquake Science 2010年第5期23卷 433-438页

作者： weitao wang Sidao Ni Baoshan wang Institute of Geophysics China Earthquake Administration Beijing 100081 China Mengcheng National Geophysical Observatory School of Earth and Space Science University of Science and Technology of China Hefei 230026 China

Long-time cross correlation of ambient noise has been proved as a powerful tool to extract Green＇s function between two receivers. The study of composition of ambient noise is important for a better understanding of this method. Previous studies confirm that ambient noise in the long period （3 s and longer） mostly consists of surface wave, and 0.25-2.5 s noise consists more of body waves. In this paper, we perform cross correlation processing at much higher frequency （30-70 Hz） using ambient noise recorded by a small aperture array. No surface waves emerge from noise correlation function （NCF）, but weak P waves emerge. The absence of surface wave in NCF is not due to high attenuation since surface waves are strong from active source, therefore probably the high ambient noise mostly consists of body wave and lacks surface wave. Origin of such high frequency body waves in ambient noise remains to be studied.

关键词： ambient noise cross correlation Green's function body wave high frequency

A Highly Efficient and Recyclable Solid Acid Catalyst for Synthesis of Spiro-oxindole Dihydroquinazolinones Under Ultrasound Irradiation

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Chemical Research in Chinese Universities 2019年第1期35卷 33-40页

作者： YANG Xiufang wang Xiaogang wang Tingting wang weitao ZHANG Jin MA Yangmin College of Chemistry & Chemical Engineering Shaanxi University of Science and Technology Xi 'an 710021.P.R.China Shaanxi Key Laboratory of Chemical Additives for Industry Shaanxi University of Science and Technology Xi'an 710021P.R.China Shaanxi Research Institute of Agricultural Products Processing Technology Shaanxi University of Science and TechnologyXi 'an 710021P.R.China

A simple,efficient and green procedure for the synthesis of spiro-oxindole dihyfroquinazolinones was developed by multi-component condensation of isatoic anhydride,aniline and isatin in the presence of a novel solid acid catalyst under ultrasound *** present environmentally benign protocol offers several advantages, such as shorter reaction time,a wide range of fimctional group tolerance,the use of an inexpensive heterogeneous catalyst,and a high yield of products via a simple experimental and work-up *** mesoporous solid acid catalyst was directly prepared from phytic acid by microwave-sulfonation method without *** phytic acid based solid acid was fully characterized by means of Fourier transform infrared spectroscopy(FTIR),Raman spectroscopy,X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and transmission electron imcroscopy(TEM).The catalyst can be recovered and reused for at least five runs without significant impact on the product yields.

关键词： Microwave-sulfonation method Solid acid catalyst Spiro-oxindole dihyfroquinazolinone

Teleseismic body waves extracted from ambient noise cross correlation between F-net and Chin Array phase Ⅱ

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Earthquake Research Advances 2022年第1期2卷 33-43页

作者： Lin Deng weitao wang Fang wang Songyong Yuan Institute of Geophysics China Earthquake AdministrationBeijing100081 Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing100081

The vertical-vertical noise cross-correlation functions(NCFs)between two seismic arrays,the Japan F-net and Chin Array phase Ⅱ,are calculated using continuous recordings during *** array interferometry to obtain bin stacked NCFs,clear body waves are retrieved at different period *** direct P waves for distance 15-40 degrees are observed between short period 3-10 s while core reflected PcP/ScS waves are more obvious for longer period 30-60 *** signal-to-noise-ratio(SNR)of the short period P waves reaches its highest point with bin widths around 20 km while SNRs of PcP and ScS increase slowly with bin *** those body waves demonstrate clear directivity with strong signals traveling from the *** time-lapse SNR variations for the PcP and ScS show correlation with the occurrence of major earthquakes,while the P-wave SNR demonstrates seasonal variations with additional contribution from major *** present results suggest teleseismic body waves can be retrieved through bin stacking,though further processing is still necessary to obtain finer waveforms such as P wave triplications.

关键词： Noise cross correlation Body waves Array interferometry ChinArray

In situ protonation in a locally flexible porous coordination polymer for enhancing proton-carrier loading and proton conductivity

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Science China Chemistry 2024年第10期67卷 3432-3437页

作者： Xianzhe Wei Jincheng Liu Yan Su weitao wang Guixiang wang Gen Zhang Ping wang Cheng Gu State Key Laboratory of Luminescent Materials and Devices Institute of Polymer Optoelectronic Materials and DevicesSouth China University of TechnologyGuangzhou 510640China College of Polymer Science and Engineering State Key Laboratory of Polymer Materials EngineeringSichuan UniversityChengdu 610065China Key Laboratory for Soft Chemistry and Functional Materials of Ministry of Education School of Chemistry and Chemical EngineeringNanjing University of Science and TechnologyNanjing 210094China

Designing efficient proton-conductive materials is crucial in fuel ***,it remains a substantial challenge because of the issues in proton mobility,proton-carrier amount,and orientation of proton host ***,we report an in-situ protonation strategy to produce a locally flexible porous coordination polymer(PCP)to enhance the proton-carrier loading and proton *** local dipole flipping of the ligand allows effective proton exchange with low activation energy,promoting interpore proton transport through the pore apertures and pore *** protonation induces substantial charges to the frameworks and enhances the interaction with proton carriers,thereby increasing the loading of the proton *** this design strategy,the resulting PCP exhibits enhanced phosphoric acid loading and extraordinary proton conductivities under both aqueous and anhydrous conditions compared to its isoreticular analog that features rigidity without proton-exchange *** work provides a new avenue for designing proton-conductive materials that combine structural dynamics with performance merits.

关键词： porous coordination polymers in-situ protonation local flexibility proton-exchange mechanism proton conduction

Imaging mantle transition zone discontinuities in southwest China from dense array ambient noise interferometry

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Earthquake Science 2018年第5期31卷 301-310页

作者： Jikun Feng Huajian Yao weitao wang Laboratory of Seismology and Physics of Earth's Interior School of Earth and Space SciencesUniversity of Science and Technology of China Mengcheng National Geophysical Observatory University of Science and Technology of China Institute of Geophysics China Earthquake Administration

Body waves retrieved from ambient noise cross-correlation functions（NCFs） have been reported by more and more recent studies in addition to the dominant recovered surface waves. And one of important applications of these recovered body waves is to investigate the structure of discontinuities within the mantle transition zone（MTZ）. In this study, clear body wave phases reflected from the MTZ discontinuities at 410 km and 660 km have been observed on the NCFs in the frequency band of 0.1–0.2 Hz from a dense regional seismic array in southwest China. The original timedomain reflected signals in the NCFs were first converted to the depth-domain NCFs based on a velocity model before they were further stacked spatially within different bins. Then the depth-domain NCFs were stacked to investigate the lateral variations of the MTZ discontinuities, that is, the 410-km and 660-km discontinuities. Our results exhibit a simple and lateral coherent P;P phase and a much more complicated P;P phase along two profiles, which are in good agreement with mineralogical prediction and recent receiver function studies in the same area. This interferometric method can provide stable reflected body wave phases mainly in the frequency band 0.1–0.2 Hz due to the secondary microseism noise, which can be potentially used for high-resolution mantle interface imaging. This approach is also a good complement to traditional imaging methods, such as receiver function imaging.

关键词： ambient noise interferometry mantle transition zone 410-km and 660-km discontinuities reflected body waves southwest China

Seismic detections of the 15 February 2013 Chelyabinsk meteor from the dense Chin Array

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Earthquake Science 2016年第4期29卷 221-233页

作者： Lu Li Baoshan wang Zhigang Peng weitao wang Key Laboratory of Seismic Observation and Geophysical Imaging Institute of Geophysics China Earthquake Administration School of Earth and Atmospheric Sciences Georgia Institute of Technology

ChinArray is a dense portable broadband seismic network to cover the entire continental China, and the Phase I is deployed along the north-south seismic belt in southwest China. In this study, we analyze seismic data recorded on the ChinArray following the February 15, 2013 Chelyabinsk （Russia） meteor. This was the largest known object entering the Earth＇s atmosphere since the 1908 Tunguska meteor. The seismic energy radiated from this event was recorded by seismic stations worldwide including the dense ChinAn＇ay that are more than 4000 km away. The weak signal from the meteor event was con- taminated by a magnitude 5.8 Tonga earthquake occur- red ~ 20 min earlier. To test the feasibility of detecting the weak seismic signals from the meteor event, we compute vespagram and perform F-K analysis to the surface-wave data. We identify a seismic phase with back azimuth （BAZ） of 329.7° and slowness of 34.73 s/deg, corre- sponding to the surface wave from the Russian meteor event （BAZ ） 325.97°）. The surface magnitude （Ms） of the meteor event is 3.94 ±0.18. We also perform similar analysis on the data from the broadband array F-net in Japan, and find the BAZ of the surface waves to be 316.61%. With the different BAZs of ChinArray and F-net, we locate the Russian meteor event at 58.80°N, 58.72°E. The relatively large mislocation （-438 km as compared with 55.15°N. 61.41°E by others） may be a result of theweak signals at teleseismic distances.

关键词： ChinArray Russian meteor event F-K analysis

Benchmark on the accuracy and efficiency of several neural network based phase pickers using datasets from China Seismic Network

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Earthquake Science 2023年第2期36卷 113-131页

作者： Ziye Yu weitao wang Yini Chen Institute of Geophysics China Earthquake AdministrationBeijing 100081China Key Laboratory of Earthquake Source Physics China Earthquake AdministrationBeijing 100081China Zhejiang Earthquake Agency Hangzhou 310013China

Seismic phase pickers based on deep neural networks have been extensively used recently,demonstrating their advantages on both performance and ***,these pickers are trained with and applied to different data.A comprehensive benchmark based on a single dataset is therefore ***,using the recently released DiTing dataset,we analyzed performances of seven phase pickers with different network structures,the efficiencies are also evaluated using both CPU and GPU *** based on F1-scores reveal that the recurrent neural network(RNN)and EQTransformer exhibit the best performance,likely owing to their large receptive *** performances are observed among PhaseNet(UNet),UNet++,and the lightweight phase picking network(LPPN).However,the LPPN models are the most *** RNN and EQTransformer have similar speeds,which are slower than those of the LPPN and ***++requires the most computational effort among the *** all of the pickers perform well after being trained with a large-scale dataset,users may choose the one suitable for their *** beginners,we provide a tutorial on training and validating the pickers using the DiTing *** also provide two sets of models trained using datasets with both 50 Hz and 100 Hz sampling rates for direct application by *** of our models are open-source and publicly accessible.

关键词： neural network deep learning seismic phase picking earthquake detection open-source science