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Automatic velocity picking based on optimal key points tracking algorithm

Petroleum science 2024年第2期21卷 903-917页

作者： Yong-Hao Wang Wen-Kai Lu Song-Bai Jin Yang Li Yu-Xuan Li Xiao-Feng Gu The Institute for Artificial Intelligence(THUAI) Tsinghua UniversityBeijing100084China State Key Laboratory of Intelligent Technology and Systems Tsinghua UniversityBeijing100084China Beijing National Research Center for Information Science and Technology(BNRist) Beijing100084China The Department of Automation Tsinghua UniversityBeijing100084China

Picking velocities from semblances manually is laborious and necessitates experience. Although various methods for automatic velocity picking have been developed, there remains a challenge in efficiently incorporating information from nearby gathers to ensure picked velocity aligns with seismic horizons while also improving picking accuracy. The conventional method of velocity picking from a semblance volume is computationally demanding, highlighting a need for a more efficient strategy. In this study, we introduce a novel method for automatic velocity picking based on multi-object tracking. This dynamic tracking process across different semblance panels can integrate information from nearby gathers effectively while maintaining computational efficiency. First, we employ accelerated density clustering on the velocity spectrum to discern cluster centers without the requirement for prior knowledge regarding the number of clusters. These cluster centers embody the maximum likelihood velocities of the main subsurface structures. Second, our proposed method tracks key points within the semblance volume. Kalman filter is adopted to adjust the tracking process, followed by interpolation on these tracked points to construct the final velocity model. Our synthetic data example demonstrates that our proposed algorithm can effectively rectify the picking errors of the clustering algorithm. We further compare the performances of the clustering method(CM), the proposed tracking method(TM), and the variational method(VM) on a field dataset from the Gulf of Mexico. The results attest that our method offers superior accuracy than CM, achieves comparable accuracy with VM, and benefits from a reduced computational cost.

关键词： Velocity picking Multi-object tracking Density clustering Kalman filter

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Long-term spatiotemporal variations of ammonia in the Yangtze River Delta region of China and its driving factors

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Journal of Environmental sciences 2025年第4期150卷 202-217页

作者： Jingkai Xue Chengzhi Xing Qihua Li Shanshan Wang Qihou Hu Yizhi Zhu Ting Liu Chengxin Zhang Cheng Liu School of Environmental Science and Optoelectronic Technology University of Science and Technology of ChinaHefei 230026China Key Lab of Environmental Optics&Technology Anhui Institute of Optics and Fine MechanicsHefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Department of Precision Machinery and Precision Instrumentation University of Science and Technology of ChinaHefei 230026China Anhui Institute of Optics and Fine Mechanics Hefei Institutes of Physical ScienceChinese Academy of SciencesHefei 230031China Key Laboratory of Precision Scientific Instrumentation of Anhui Higher Education Institutes University of Science and Technology of ChinaHefei 230026China Institute of Physical Science and Information Technology Anhui UniversityHefei 230601China Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China School of Earth and Space Sciences University of Science and Technology of ChinaHefei 230026China School of Environmental Science and Engineering Suzhou University of Science and TechnologySuzhou 215009China

This study focuses on the spatiotemporal distribution,urban-rural variations,and driving factors of ammonia Vertical Column Densities(VCDs)in China’s Yangtze River Delta region(YRD)from 2008 to *** data from the Infrared Atmospheric Sounding Interfer-ometer(IASI),Generalized Additive Models(GAM),and the GEOS-Chem chemical transport model,we observed a significant increase of NH_(3)VCDs in the YRD between 2014 and *** spatial distribution analysis revealed higher NH_(3)concentrations in the northern part of the YRD region,primarily due to lower precipitation,alkaline soil,and intensive agricul-tural ***_(3)VCDs in the YRD region increased significantly(65.18%)from 2008 to *** highest growth rate occurs in the summer,with an annual average growth rate of 7.2%during the period from 2014 to *** emissions dominated NH_(3)VCDs during spring and summer,with high concentrations primarily located in the agricultural areas adjacent to densely populated urban *** within several large urban areas have been discovered to exhibit relatively stable variations in NH_(3)*** rise in NH_(3)VCDs within the YRD region was primarily driven by the reduction of acidic gases like SO_(2),as emphasized by GAM modeling and sensitivity tests using the GEOS-Chem *** concentration changes of acidic gases contribute to over 80%of the interannual variations in NH_(3)*** emphasizes the crucial role of environmental policies targeting the reduction of these acidic *** emission control is urgent tomitigate environmental hazards and secondary particulate matter,especially in the northern YRD.

关键词： Yangtze River Delta Ammonia Spatiotemporal distribution Driving factors

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High-excited-state splitting and multimode vibrational coupling in Mn^(4+)-activated fluoride phosphor

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science China(Physics,Mechanics & Astronomy) 2024年第3期67卷 95-101页

作者： Debao Zhang Wanggui Ye Xuguang Cao Ji Zhou Fei Tang Changcheng Zheng Jiqiang Ning Shijie Xu Department of Optical Science and Engineering School of Information Science and TechnologyFudan University Shanghai 200438China Jiangsu Key Laboratory of Advanced Laser Materials and Devices Schoolof Physics and Electronic Engineering Jiangsu Normal UniversityXuzhou 221116China Division of Natural and Applied Sciences Duke Kunshan UniversityKunshan 215316China

Excited-states play a crucial role in the optical absorption and luminescence of solids and hence their accurate information is highly desired. Herein, we attempt to seize the excited-states information of Mn^(4+)ions in K_(2)SiF_(6) microcrystals via measuring and calculating their variable-temperature photoluminescence excitation(PLE) spectra. At cryogenic temperatures, an unpredicted splitting of the high-excited-state is observed. Moreover, the two-split high-excited-state levels are further revealed to primarily couple with the two hyperfine split modes of quasi-localized ν2 vibration in the distorted Mn-F_(6) octahedral configuration,whereas the coupling strengths are found to be substantially different from each other. The slightly split vibrational mode is firmly supported by the low-temperature Raman spectra. Jahn-Teller lattice distortion is believed to be responsible for the observed splitting of the electronic high-excited-state and the quasi-localized vibrational mode.

关键词： splitting of excited-state photoluminescence excitation spectrum electron-phonon coupling Jahn-Teller effect

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Continuous Health State Monitoring of High-Voltage Circuit Breakers

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IEEE Access 2025年 13卷 89819-89830页

作者： Hsu, Chi-Ching Frusque, Gaetan Fink, Olga Franck, Christian M. Institute for Power Systems and High Voltage Technology High-Voltage Laboratory Department of Information Technology and Electrical Engineering ETH Zürich Zurich8092 Switzerland Intelligent Maintenance and Operations Systems Ècole Polytechnique Fédérale de Lausanne Lausanne1015 Switzerland

Circuit breakers (CBs) are renowned for their high reliability and long lifespan. As a result, many CBs installed decades ago are now approaching their predefined end of service life. However, this predefined service life does not always reflect the actual condition, as some may still be far from reaching their true end-of-life, depending on their operating conditions and history. To assess their true lifetime, continuous condition monitoring is essential. While previous studies have effectively demonstrated the ability to distinguish between different CB fault types, the evolution of CB degradation remains unclear when faults are artificially introduced. This paper investigates the health condition of two high-voltage CBs continuously through run-to-failure experiments. A comprehensive dataset was collected for all opening and closing operations with various sensors such as vibration, coil current, and travel curve and has been made publicly available for further analysis. Furthermore, features were derived from the sensor data, revealing distinct degradation trajectories over time that can be used to monitor the condition of the CBs. This paper highlights the degradation patterns of these features, some of which are well-suited for continuous condition monitoring due to their gradual changing trend over time that likely correlates with the true degradation condition, while others are less useful as they show abrupt changes only before or at failure. By leveraging these features, we can progress beyond the focus of previous research using only fault diagnosis towards fault prognosis. This shift opens the possibility for accurate prediction of the CB condition over time, enabling more effective maintenance strategies. © 2013 IEEE.

关键词： Repair

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A Memristive Chaotic System: Attractor Self-Reproducing, Amplitude Control and Offset Boosting

A Memristive Chaotic System: Attractor Self-Reproducing, Amp...

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2023 IEEE International Conference on Memristive Computing and Applications, ICMCA 2023

作者： Li, Yongxin Li, Chunbiao Gao, Yikai Zhang, Xin Volos, Christos Yu, Wanning Sch. of Electronic and Information Engineering Nanjing University of Information Science Technology Nanjing China School of Artificial Intelligence Nanjing University of Information Science & Technology Nanjing China Aristotle University of Thessaloniki Laboratory of Nonlinear Systems Circuits & Compleixty Greece

ISBN: (纸本)9798350316230

Two flux-controlled memristors sharing the same internal variable and the same resistor function are introduced into the simplest variable boostable system VB5 for constructing the 3-D memristive chaotic oscillator. The offset booster is well inherited from the original chaotic system for attractor boosting, which makes the corresponding oscillation controlled on different positions by a single offset constant. Meanwhile, the periodic resistor function makes attractors self-reproducing and produces infinitely many attractors under different initial conditions. Furthermore, the property of rotational symmetry implies an extra partial amplitude control. The amplitude of the system variables x and z signal can be modified by a single non-bifurcation parameter. Analog circuit simulation based on Pspice shows agreement with the theoretical and numerical analysis. © 2023 IEEE.

关键词： Chaotic systems

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IRMIRS:Inception-ResNet-Based Network for MRI Image Super-Resolution

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Computer Modeling in engineering & sciences 2023年第8期136卷 1121-1142页

作者： Wazir Muhammad Zuhaibuddin Bhutto Salman Masroor Murtaza Hussain Shaikh Jalal Shah Ayaz Hussain Department of Electrical Engineering Balochistan University of Engineering and TechnologyKhuzdar89100Pakistan Department of Computer Systems Engineering Balochistan University of Engineering and TechnologyKhuzdar89100Pakistan Department of Mechanical Engineering Balochistan University of Engineering and TechnologyKhuzdar89100Pakistan Department of Mechanical Engineering National Taiwan University of Science and Technology10607Taiwan Department of Information Systems Kyungsung UniversityBusan613010South Korea

Medical image super-resolution is a fundamental challenge due to absorption and scattering in *** challenges are increasing the interest in the quality of medical *** research has proven that the rapid progress in convolutional neural networks(CNNs)has achieved superior performance in the area of medical image ***,the traditional CNN approaches use interpolation techniques as a preprocessing stage to enlarge low-resolution magnetic resonance(MR)images,adding extra noise in the models and more memory ***,conventional deep CNN approaches used layers in series-wise connection to create the deeper mode,because this later end layer cannot receive complete information and work as a dead *** this paper,we propose Inception-ResNet-based Network for MRI Image Super-Resolution known as *** our proposed approach,a bicubic interpolation is replaced with a deconvolution layer to learn the upsampling ***,a residual skip connection with the Inception block is used to reconstruct a high-resolution output image from a low-quality input *** and qualitative evaluations of the proposed method are supported through extensive experiments in reconstructing sharper and clean texture details as compared to the state-of-the-art methods.

关键词： Super-resolution magnetic resonance imaging ResNet block inception block convolutional neural network deconvolution layer

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Highly efficient ozone elimination by metal doped ultra-fine Cu_(2)O nanoparticles

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Journal of Environmental sciences 2023年第12期134卷 108-116页

作者： Anqi Wang Le Zhang Jian Guan Xiaoze Wang Guojun Ma Guijun Fan Hang Wang Ning Han Yunfa Chen State Key Laboratory of Multiphase Complex Systems Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100049China Key Laboratory of Science&Technology on Particle Materials Institute of Process EngineeringChinese Academy of SciencesBeijing 100190China School of Metallurgical Engineering Xi’an University of Architecture and TechnologyXi’an 710055China

Nowadays,ozone contamination becomes dominant in air and thus challenges the research and development of cost-effective *** this study,metal doped Cu_(2)O catalysts are synthesized via reduction of Cu^(2+)by ascorbic acid in base solutions containing doping metal *** results show that compared with pure Cu_(2)O,the Mg^(2+)and Fe^(2+)dopants enhance the O_(3)removal efficiency while Ni2+depresses the *** specific,Mg-Cu_(2)O shows high O3removal efficiency of 88.4%in harsh environment of 600,000 mL/(g·hr) space velocity and 1500 ppmV O_(3),which is one of the highest in the *** and electron paramagnetic spectroscopy characterization shows higher concentration of crystal defects induced by the Mg^(2+)dopants,favoring the *** in-situ diffuse reflectance Fourier transform infrared spectroscopy shows the intermediate species in the O_(3)degradation process change from O_(2)^(2-)dominant of pure Cu_(2)O to O_(2)^(-)dominant of Mg-Cu2O,which would contribute to the high *** these results show the promising prospect of the Mg-Cu_(2)O for highly efficiency O_(3)removal.

关键词： Ozone catalyst Cu_(2)O Dopant Ultra-fine nanoparticles

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Lip Reading with 3D Convolutional and Bidirectional LSTM Networks on the GRID Corpus 2

Lip Reading with 3D Convolutional and Bidirectional LSTM Net...

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2nd IEEE International Conference on Networks, Multimedia and information technology, NMITCON 2024

作者： Prashanth, B.S. Manoj Kumar, M.V. Puneetha, B.H. Lohith, R. Darshan Gowda, V. Chandan, V. Sneha, H.R. Nitte Meenakshi Institute of Technology Department of Information Science & Engineering Karnataka Bangalore560064 India Bapuji Institute of Engineering and Technology Department of Computer Science and Business Systems Karnataka Davanagere577004 India

ISBN: (纸本)9798350372892

In recent years, the application of artificial intelligence has revolutionized the field of lip reading by enabling the development of sophisticated models capable of accurately interpreting lip movements from video data. This work presents a novel deep learning approach to lip reading, focused on decoding spoken text from video sequences of lip movements. Traditional lip reading methods involve separate stages for visual feature design and prediction. The proposed system utilizes an endto-end deep learning model to directly map video frames to text transcriptions, leveraging 3D convolutional neural networks and bidirectional Long Short-Term Memory. By analyzing visual cues from lipmotions, the system can interpret speech, improving accessibility for individuals with hearing impairments and enabling communication in noisy environments. Compared to existing lip reading techniques, the deep learning model achieves superior performance on benchmark datasets, demonstrating its effectiveness in this challenging task. The model has achieved a character error rate of 1.54% and a word error rate of 7.96% on the best model. © 2024 IEEE.

关键词： Convolutional neural networks

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Improving atmospheric pressure vertical correction model using Gaussian function

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Geodesy and Geodynamics 2025年第1期16卷 67-74页

作者： Baoshuang Zhang Junyu Li Lilong Liu Yibin Yao Liangke Huang Chao Ren Hongchang He Tengxu Zhang Yuxin Wang College of Geomatics and Geoinformation Guilin University of TechnologyGuilin 541004China Guangxi Key Laboratory of Spatial Information and Geomatics Guilin 541004China School of Geodesy and Geomatics Wuhan UniversityWuhan 430079China Schoolof Resources and Environmental Science and Engineering Hubei University of Science and TechnologyXianning 437100China

The Zenith Hydrostatic Delay(ZHD)is essential for high-precision Global Navigation Satellite System(GNSS)and Very Long Baseline Interferometry(VLBI)data *** estimation of ZHD relies on in situ atmospheric pressure,which is primarily variable in the vertical *** atmospheric pressure is either site-specific or has limited spatial coverage,necessitating vertical corrections for broader *** study introduces a model that uses a Gaussian function for the vertical correction of atmospheric pressure when in situ meteorological observations are *** with the fifth-generation European Centre for Medium-Range Weather Forecasts reanalysis(ERA5)reveals an average Bias and RMS for the new model of 0.31 h Pa and 2.96 h Pa,*** corresponds to improvements of 37.5%and 80.3%in terms of RMS compared to two commonly used models(T0and Tvmodels)that require in situ meteorological observations,*** validation with radiosonde data shows an average Bias and RMS of 1.85 h Pa and 4.87 h Pa,corresponding to the improvement of 42.8%and 71.1%in RMS compared with T0and Tv models,*** accuracies are sufficient for calculating ZHD to an accuracy of 1 mm by performing atmospheric pressure vertical *** new model can correct atmospheric pressure from meteorological stations or numerical weather forecasts to different heights of the troposphere.

关键词： Atmospheric pressure Vertical correction Zenith hydrostatic delay(ZHD) Gauss function ERA5

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Workspace,stiffness analysis and design optimization of coupled active-passive multilink cable-driven space robots for on-orbit services

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Chinese Journal of Aeronautics 2023年第2期36卷 402-416页

作者： Jianqing PENG Haoxuan WU Tianliang LIU Yu HAN School of Intelligent Systems Engineering Shenzhen Campus of Sun Yat-sen UniversityShenzhen 518109China Guangdong Provincial Key Laboratory of Fire Science and Technology Guangzhou 510006China School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China

The use of space robots(SRs)for on-orbit services(OOSs)has been a hot research topic in recent ***,the space unstructured environment(i.e.:confined spaces,multiple obstacles,and strong radiation interference)has greatly restricted the application of *** coupled active-passive multilink cable-driven space robot(CAP-MCDSR)has the characteristics of slim body,flexible movement,and electromechanical separation,which is very suitable for extreme space ***,the dynamic and stiffness modeling of CAP-MCDSRs is challenging,due to the complex coupling among the active cables,passive cables,joints,and the *** deal with these problems,this paper proposes a workspace,stiffness analysis and design optimization method for such type of ***,the multi-coupling kinematics relationships among the joint,cables and the end-effector are *** on hybrid series-parallel characteristics,the improved coupled active–passive(CAP)dynamic equation is ***,the maximum workspace,the maximum stiffness,and the minimum cable tension are resolved,among them,the overall stiffness is the superposition of the stiffness produced by the active and the passive ***,the workspace,the stiffness,and the cable tension are analyzed by using the nonlinear optimization method(NOPM).Finally,an 8-DOF CAP-MCDSR experiment system is built to verify the proposed modeling and trajectory tracking *** proposed modeling and analysis results are very useful for practical space applications,such as designing a new CAP-MCDSR,or utilizing an existing CAP-MCDSR system.

关键词： Coupled active–passive(CAP) Hybrid series-parallel Multilink cable-driven space robot(MCDSR) Nonlinear optimization(NOP) On-orbit services(OOSs) Robotics Space

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