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Novel integration of PSO-enhanced damage mechanics and finite element method for predicting medium-low-cycle fatigue life in perforated structures

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Chinese Journal of Aeronautics 2025年第2期38卷 128-142页

作者： Qianyu XIA Zhixin ZHAN Yue MEI Yanjun ZHANG Weiping HU Qingchun MENG National Key Laboratory of Strength and Structural Integrity School of Aeronautical Science and EngineeringBeihang UniversityBeijing 100191China Department of Engineering Mechanics Dalian University of TechnologyDalian 116023China AVIC The First Aircraft Institute Xi’an 710089China

In this research,we introduce an innovative approach that combines the Continuum Damage Mechanics-Finite Element Method(CDM-FEM)with the Particle Swarm Optimization(PSO)-based technique,to predict the Medium-Low-Cycle Fatigue(MLCF)life of perforated ***,fatigue tests are carried out on three center-perforated structures,aiming to assess their fatigue life under various strengthening *** tests reveal significant variations in fatigue life,accompanied by an examination of crack initiation through the analysis of fatigue fracture ***,an innovative fatigue life prediction methodology is applied to perforated structures,which not only forecasts the initiation of fatigue cracks but also traces the progression of damage within these *** leverages an elastoplastic constitutive model integrated with damage and a damage evolution model under cyclic *** accuracy of this approach is validated by comparison with test results,falling within the three times error ***,we explore the impact of various strengthening techniques,including cross-sectional reinforcement and cold expansion,on the fatigue life and damage evolution of these *** is achieved through an in-depth comparative analysis of both experimental data and computational predictions,which provides valuable insights into the behavior of perforated structures under fatigue conditions in practical applications.

关键词： Continuum damage mechanics Medium-low-cycle fatigue Particle swarm optimization Life prediction Perforated structures

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Spatial Coded Modulation:Coding over Antennas

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China Communications 2024年第11期21卷 104-122页

作者： Luo Junshan Wang Fanggang Wang Shilian School of Electronic Science National University of Defense TechnologyChangsha 410073China State Key Laboratory of Rail Traffic Control and Safety Beijing Jiaotong UniversityBeijing 100044China

In spatial modulation systems,the reliability of the active antenna detection is of vital importance since the modulated symbols tend to be correctly demodulated when the active antennas are accurately *** this paper,we propose a spatial coded modulation(SCM)scheme,which improves the accuracy of the active antenna detection by coding over the transmit ***,the antenna activation pattern in the SCM corresponds to a codeword in a properly designed codebook with a larger minimum Hamming distance than the conventional spatial *** the minimum Hamming distance increases,the reliability of the active antenna detection is directly enhanced,which yields a better system *** addition to the reliability,the proposed SCM scheme also achieves a higher capacity with the identical antenna configuration compared to the conventional *** optimal maximum likelihood detector is first ***,a low-complexity suboptimal detector is proposed to reduce the computational *** derivations of the channel capacity and the bit error rate are presented in various channel *** derivation on performance bounding is also provided to reveal the insight of the benefit of increasing the minimum Hamming *** results validate the analysis and demonstrate that the proposed SCM outperforms the conventional spatial modulation techniques in both channel capacity and system reliability.

关键词： antenna correlation channel capacity Hamming distance reliability spatial modulation

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Lightning Current Sweep Damage Test System Based on Energy Conversion 19th

Lightning Current Sweep Damage Test System Based on Energy C...

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19th Annual Conference of China Electrotechnical Society, ACCES 2024

作者： Duan, Zemin Tong, Chen Qu, Minglei Huang, Yeyuan School of Electrical Engineering and Automation Hefei University of Technology Hefei China National Key Laboratory of Electromagnetic Information Control and Effects Hefei China Key Laboratory of Strong Electromagnetic Environment Protection Technology Aviation Science and Technology Hefei China Key Laboratory of Aircraft Lightning Protection of Anhui Province Hefei China

ISBN: (纸本)9789819608966

To solve the problem of difficulty in simulating dynamic sweep damage of lightning current, this paper established a new lightning current sweep damage test system using motors and launch wheels. The speed of the test piece and the temperature during the damage process were measured by high-speed cameras and infrared thermometers. The speed of the test piece was 34 m/s and the temperature exceeded 600 °C. At the same time, a new lightning current component C generator topology and control method were proposed. The load current and inductor current were used to form a double closed-loop PI negative feedback controller to ensure that the load current meets the standard output requirements. The study in this paper has certain guiding significance for the direct effect sweep damage assessment of composite materials and the design of lightning current generators. © Beijing Paike Culture Commu. Co., Ltd. 2025.

关键词： High speed cameras

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An improved mask R-CNN example segmentation algorithm based on RGB-D

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International Journal of Wireless and Mobile Computing 2024年第3期26卷 302-309页

作者： Li, Gongfa Li, Boao Jiang, Du Tao, Bo Yun, Juntong Key Laboratory of Metallurgical Equipment and Control Technology of Ministry of Education Wuhan University of Science and Technology Hubei Wuhan China Hubei Key Laboratory of Mechanical Transmission and Manufacturing Engineering Wuhan University of Science and Technology Hubei Wuhan China National Demonstration Centre for Experimental Mechanical Education Wuhan University of Science and Technology Hubei Wuhan China

Combining the characteristics of RGB images and depth images, we propose a reverse fusion instance segmentation algorithm that effectively combines the advantages of RGB and depth information by fusing high-level semantic features with low-level edge detail features. The algorithm uses RGB and depth information in RGB-D images, extracts features from RGB and depth images separately using a Feature Pyramid Network (FPN) and upsamples the high-level features to the same size as the bottommost features. Subsequently, we apply the inverse fusion method to fuse the high-level features with the low-level features. At the same time, a mask optimisation structure is introduced in the mask branch to achieve RGB-D reverse fusion instance segmentation. Experimental results show that this reverse fusion feature model gives satisfactory performance in RGB-D instance segmentation. On the basis of using ResNet-101 as the backbone network, the average accuracy is improved by 10.6% compared with Mask R-CNN without fusing depth information. Copyright © 2024 Inderscience Enterprises Ltd.

关键词： Inverse problems

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Performance Evaluation and Transmitter Optimization for AN-Aided FH Communication Against Time Misalignment

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China Communications 2025年第3期22卷 86-103页

作者： Song Changqing Lin Lang Qin Lizhi Xiao Fei Zhao Hongzhi Shao Shihai National Key Laboratory of Wireless Communications University of Electronic Science and Technology of ChinaChengdu 611731China The Laboratory of Electromagnetic Space Cognition and Intelligent Control Beijing 100089China The Thirtieth Research Institude of China Electronic Science and Technology Group Corporation Chengdu 610093China

To guarantee secure communication against eavesdropping and malicious attack,an artificial noise(AN)-aided frequency-hopping(FH)architecture is adopted in this *** the inevitable time misalignment between the received signal and locally reconstructed AN will deteriorate the AN cancellation performance,yielding significant secrecy degradation at the FH *** view of this,first,the AN cancellation performance under time misalignment is evaluated via signal to AN-plus-noise ratio,and the system secrecy is analyzed via secrecy ***,to mitigate the performance degradation raised by time misalignment,the transmitting power allocation scheme for AN and confidential signal(CS)is optimized,and the optimal hopping period is ***,the obtained conclusions in both the performance evaluation and transmitter optimization sections hold no matter whether the eavesdropper can realize FH synchronization or *** verify that time misalignment will raise non-negligible performance ***,the power ratio of AN to CS should decrease as time misalignment increases,and for perfect time synchronization,the transmitting power of AN and CS should be *** addition,a longer hopping period is preferred for secrecy enhancement when time misalignment gets exacerbated.

关键词： artificial noise(AN)cancellation hopping period design power allocation time misalignment

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Evolution hydrothermal aging resistance mechanism study of zirconium and manganese doped CeO_(2)catalysts in soot catalytic combustion based on low Miller indices crystal surface effect

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Journal of Rare Earths 2024年第7期42卷 1272-1281,I0003页

作者： Zonglin Li Pan Wang Hong Ni Chengcheng Ao Lidong Zhang Hefeng Zhang Kai Li School of Automotive and Traffic Engineering Jiangsu UniversityZhenjiang212013China State Environmental Protection Key Laboratory of Vehicle Emission Control and Simulation Chinese Research Academy of Environmental ScienceBeijing100012China National Synchrotron Radiation Laboratory University of Science and Technology of ChinaHefei230026China

The thermogravimetric analysis(TGA)experiments were carried out to reveal the mechanism of Zr and Mn doping on catalytic activity of CeO_(2)catalyst both fresh and after hydrothermal aging,and the lattice morphology and valence changes were characterized by means of Brunauer-Emmett-Teller(BET)method,X-ray diffraction(XRD),X-ray photoelectron spectroscopy(XPS),and H_(2)-temperature programmed reduction(H_(2)-TPR).Density functional theory(DFT)and molecular thermodynamics calculations were applied to investigate the change in catalytic activity,crystal surface energy and crystal morphology caused by hydrothermal *** maximum reaction rate temperature of fresh Mn/CeO_(2)(389℃)is similar to that of CeO_(2)(371℃)and lower than that of Zr/CeO_(2)(447℃),but the catalytic performance of CeO_(2)decreases more severely after hydrothermal *** catalyst crystals show different degrees of crystal surface migration after hydrothermal aging,which leads to the reduction of Ce^(3+)/Ce^(4+) ratio and the active sites *** calculations indicate that the doping of Zr and Mn reduces the surface energy of the low Miller indices surface and increases the oxygen vacancy formation energy,leading to better thermal stability and lower catalytic *** Zr and Mn doping also changes the adsorption energy and Gibbs free energy of H_(2)O,which dominates the migration of(111)to(110)and(100)in the vapor *** crystal surface migration mechanism of CeO_(2)catalysts doped with Zr and Mn induced by H_(2)O molecules at high temperature obtained in this study can provide a valuable addition to the regeneration of CeO_(2)catalysts in the after-treatment systems of diesel engines.

关键词： Soot CeO_(2)-based catalyst CDPF Rare earth metal oxides DFT calculations

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An Optimization Method for the Swing of a Quadrotor Flight Suspension System 25

An Optimization Method for the Swing of a Quadrotor Flight S...

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25th IEEE China Conference on System Simulation technology and its Application, CCSSTA 2024

作者： Yang, Sen Zang, Xinlian Tong, Jigang Xie, Tian Jin, Xin Tianjin University of Technology The School of Electrical Engineering and Automation Tianjin China AVIC Xi'an Flight Automatic Control Research Institute National key laboratory of science and technology on aircraft control Xi'an China

ISBN: (纸本)9798350366600

The aim of this study is to explore optimization control methods for suspension systems during the flight of quadcopters. The traditional control method of suspension system has some problems such as oscillation and instability, so an optimization scheme based on Gaussian pseudo-general algorithm is proposed in this paper. Through numerical simulation and actual flight test, the effectiveness of the optimization algorithm in improving system stability and reducing oscillation amplitude is verified. At the same time, this study conducted a comparative analysis of the suspension system of the quadrotor vehicle and the free fall body, and the optimization algorithm is found to be feasible and can well improve the control accuracy and stability of the system, and provide strong support for the safety of the quadrotor vehicle in various application scenarios. © 2024 IEEE.

关键词： Flight testing

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Making waste profitable: Efficient recovery of metallic iron from jarosite residues

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Chinese Journal of Chemical Engineering 2024年第7期71卷 66-76页

作者： Songshan Zhou Yunhui Han Rong Huang Yin Huang Qingyuan Dong Haiyin Gang Jinchuan Qin Xi Yu Xiangfei Zeng Wenxing Cao Jiqin Wang Shaoqin Chen Rong Wang Mengjun Chen Key Laboratory of Solid Waste Treatment and Resource Recycle(SWUST) Ministry of EducationSouthwest University of Science and TechnologyMianyang 621010China School of Environment Key Laboratory of Yellow River and Huai River Water Environment and Pollution ControlMinistry of EducationHenan Normal UniversityXinxiang 453007China School of National Defense Science and Technology College SWUST Ministry of EducationSouthwest University of Science and TechnologyMianyang 621010China

To address the hazardous by-product of zinc smelting and resource utilization of jarosite residue,this study applies an electric field-assisted hot acid treatment to completely recycle iron(Fe).This innovative approach aims to enhance the leaching efficiency of Fe from jarosite *** introduction of an electric field changes the charge distribution on the surface of the particles to enhance ions and electrons exchange and promotes the collision between particles to strengthen reaction *** on the above,the leaching efficiency of Fe in jarosite under sulfuric acid attack has improved *** result shows that Fe leaching efficiency reaches 98.83%,which is increased by 28%under the optimal experimental conditions:current density of 30 mA·cm^(-2),H_(2)SO_(4) concentration of 1.5 mol·L^(-1),solid-liquid ratio of 70 g·L^(-1),temperature of 80℃ and time of 12 *** kinetics calculations show that the apparent activation energy is 16.97 kJ·mol^(-1) and the leaching of jarosite residue is controlled by a mixture of chemical reaction and diffusion,as well as the temperature and concentration of the leaching solution have an influence on *** work provides a feasible idea for the efficient leaching of Fe from jarosite residue.

关键词： Jarosite residue Electric filed Leaching kinetics

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A Enhanced Feature Extraction for 3D Object Detection 25

A Enhanced Feature Extraction for 3D Object Detection

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25th IEEE China Conference on System Simulation technology and its Application, CCSSTA 2024

作者： Meng, Qingao Tong, Jigang Yang, Sen Xie, Tian Jin, Xin Tianjin University of Technology The School of Electrical Engineering and Automation Tianjin China Avic Xi'an Flight Automatic Control Research Institute National Key Laboratory of Science and Technology on Aircraft Control Xi'an China

ISBN: (纸本)9798350366600

3D object detection is crucial for autopilot and augmented reality applications. However, accurate feature extraction is the key to achieve high-precision detection, but traditional methods face the challenges of information loss and computational inefficiency. To address this, we propose an enhanced feature extraction method. We first divide the 3D space into voxel grids of varying scales. Then, using 3D sparse convolution, we extract features which are compressed along the Z axis to form BEV (Bird's Eye View) feature images. An efficient multi-scale attention mechanism is then employed to enhance these BEV features. The refined feature map is subsequently located and classified through a CT-stacking module and RPN (Region Proposal Network). Voxel features from the proposal and 3D backbone are passed through a voxel RoI pool to directly extract RoI features from the 3D features for further refinement. Finally, a cascaded attention network refines the proposal and strengthens confidence prediction. Experiments on test set validate our method effectiveness, showing improved accuracy over traditional voxel methods. Overall, this enhanced feature extraction technique offers a promising solution for 3D target detection, particularly in scenarios demanding high real-time performance and precision. © 2024 IEEE.

关键词： Feature extraction

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Metabolomics and gene expression levels reveal the positive effects of teaseed oil on lifespan and aging process in Caenorhabditis elegans

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Food science and Human Wellness 2023年第4期12卷 1391-1401页

作者： Yanan Wang Jiachen Shi Kun Liu Yu Wang Yongjiang Xu Yuanfa Liu State Key Laboratory of Food Science and Technology National Engineering Research Center for Functional FoodNational Engineering Laboratory for Cereal Fermentation TechnologyCollaborative Innovation Center of Food Safety and Quality Control in Jiangsu ProvinceSchool of Food Science and TechnologyJiangnan UniversityWuxi 214122China

As an irreplaceable dietary constituent,lipids play a vital important role in health,but their effects on aging process and longevity are still not well known *** this paper,the metabolic profiling and gene expression levels of Caenorhabditis elegans were investigated to explore the effects of different edible oils on senescence and *** results showed that teaseed oil(TO)could prolong the life expectancy and slow down the aging process of *** to the control group,the intake of lard oil(LO)and TO increased the expression levels of genes related to inhibition of protein aggregation(akt-1,daf-16,hsf-1,hsp-16.2)and lipid metabolism(daf-7,daf-1,mdt-15,lipl-4,fat-5,fat-6,fat-7),with a more significant alteration in TO *** revealed that palm oil can upregulated plenty of fatty acids(palmitic acid,stearic acid,tetracosanoic acid),together with some amino acids(tryptophan,L-aspartate,L-valine)and carbohydrate(D-glucose),while the trend was opposite in TO ***,moderate-to-strong correlations were found between differential metabolites and changed *** general,this paper claimed that TO could prolong lifespan and slow down aging process via regulating the lipids,amino acids and carbohydrates metabolism.

关键词： Caenorhabditis elegans Lipids Lifespan Food omics Gene expression

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