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Constraining the Earth-mass Primordial Black Hole Mergers Model of the Non-repeating FRBs Using the First CHIME/FRB Catalog

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Research in Astronomy and Astrophysics 2024年第9期24卷 76-82页

作者： Min meng Qiu-Ju huang Can-Min Deng Guangxi Key Laboratory for Relativistic Astrophysics School of Physical Science and TechnologyGuangxi UniversityNanning 530004China

In this paper,we upgrade the constraints for the Earth-mass primordial black hole mergers model based on the first Canadian Hydrogen Intensity Mapping Experiment(CHIME)/fast radio burst(FRB)*** the null hypothesis that the observed non-repeating FRBs originate from Earth-mass primordial black hole mergers,we find that how the charges were distributed in the primordial black hole population is well described by a double powerlaw function with typical charge value of law function with typical charge value of q_(c)/10^(-5)=1.60_(-0.28)^(+0.28),where the power-law index α_(1)=2.33_(-0.18)^(+0.15) for q

关键词： black hole physics (stars:)gamma ray burst:general (cosmology:)dark matter

Flexible MXene/sodium alginate composite fabric with high structural stability and oxidation resistance for electromagnetic interference shielding

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Nano Research 2024年第6期17卷 5326-5335页

作者： Hao-Wen Zhang Lu-Yao Yang meng-Lin huang Ming-Hua Cheng Zhe-Sheng Feng Fanbin meng Zifeng Lin Yan Wang School of Materials and Energy University of Electronic Science and Technology of ChinaChengdu 610054China Laboratory of Advanced Technologies of Materials(Ministry of Education) School of Materials Science and EngineeringSouthwest Jiaotong UniversityChengdu 610031China College of Materials Science and Engineering Sichuan UniversityChengdu 610065China

Wearable electromagnetic interference(EMI)shielding fabrics with excellent electromagnetic shielding performance,oxidation resistance,and structural stability are highly demanded for the rapid development of electronic devices and wireless *** are metallic conductive materials with exceptional EMI shielding properties,but they are prone to oxidation in air and have poor structural stability and durability on fabric ***,we present a one-step assembly method to fabricate fabrics coated with MXenes and polymeric sodium alginate(SA)composite(MXene-SA).SA protects MXenes from oxidation and forms a stable interlayer structure by bonding to *** MXene-SA coated fabrics are breathable and flexible,and have a low sheet resistance of 2.12±0.08Ω/sq and a high EMI shielding performance of 37.05 dB at X-band,which is comparable to the best 42.31 ***,the MXene-SA coated fabrics exhibit high structural stability and oxidation resistance under various conditions of sonication disintegration,mechanical abuse,chemical corrosion,and humidity,compared to pure MXenes coated *** believe that the wearable and high-performance MXene-SA fabrics have great potential for the next generation of ultra-portable and wearable EMI shielding products.

关键词： MXenes electromagnetic interference shielding fabric one-step assembly

Metal-free Optical Pressure Sensor with High Sensitivity and Extensive Range

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CSEE Journal of Power and Energy Systems 2024年第3期10卷 1291-1300页

作者： Mao Ji meng huang Haomin Lyu Sheng Shi Bo Qi Chengrong Li State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources North China Electric Power UniversityBeijing 102206China IEEE CSEE

Pressure monitoring of a transformer oil tank can grasp the pressure change process caused by gas production when severe internal defects occur and take timely measures to ensure the safe operation of the *** pressure sensors generally use metal encapsulation or have an air cavity structure,threatening the transformer’s insulation if it is directly used inside the *** this end,this paper proposes a method for developing a high-sensitivity,large-range,and metallizationfree optical pressure sensing device with temperature *** grating is encapsulated by fluorosilicone rubber and supplemented by an epoxy resin shielding shell on the *** the same time,a double-grating vertical arrangement is adopted to improve pressure measurement sensitivity,further avoiding the influence of temperature rise caused by a defect of the transformer on the measurement result of the *** addition,by optimizing the geometric structure of the internal sensitizing element,pre-stretching length of the fiber grating,gap distance,and other parameters,probe size can be reduced while ensuring the sensor’s *** show the proposed method can meet the requirements of sensor fabrication with different sensitivities and ranges,and to a certain extent,both high sensitivity and extensive ranges can be taken into *** sensitivity of the fabricated prototype is 15 pm/kPa,and the range is about 0.2 *** the same time,the metal-free feature of the sensor makes it suitable for use in various oil-immersed power *** records oil pressure changes caused by oil discharge breakdown,making it sensitive to small pressure changes in early failures.

关键词： Highly sensitive extensive range optical sensing no metallization pressure perception temperature compensation transformer

Fault Diagnosis Scheme for Railway Switch Machine Using Multi-Sensor Fusion Tensor Machine

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Computers, Materials & Continua 2024年第6期79卷 4533-4549页

作者： Chen Chen Zhongwei Xu meng Mei Kai huang Siu Ming Lo School of Electronic and Information Engineering Tongji UniversityShanghai201804China Department of Architecture and Civil Engineering City University of Hong KongHong KongChina School of Computer Engineering Jimei UniversityXiamen361021China

Railway switch machine is essential for maintaining the safety and punctuality of train operations.A data-driven fault diagnosis scheme for railway switch machine using tensor machine and multi-representation monitoring data is developed *** existing methods,this approach takes into account the spatial information of the time series monitoring data,aligning with the domain expertise of on-site manual ***,a multi-sensor fusion tensor machine is designed to improve single signal data’s limitations in insufficient ***,one-dimensional signal data is preprocessed and transformed into two-dimensional ***,the fusion feature tensor is created by utilizing the images of the three-phase current and employing the CANDE-COMP/PARAFAC(CP)decomposition ***,the tensor learning-based model is built using the extracted fusion feature *** developed fault diagnosis scheme is valid with the field three-phase current *** experiment indicates an enhanced performance of the developed fault diagnosis scheme over the current approach,particularly in terms of recall,precision,and F1-score.

关键词： Railway switch machine tensor machine fault diagnosis

Fatigue Crack Initiation and Propagation Dominated by Crystallographic Factors in TiB/near α-Ti Composite

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Acta Metallurgica Sinica(English Letters) 2024年第5期37卷 763-776页

作者： Fanchao meng Rui Zhang Shuai Wang Fengbo Sun Run Chen Lujun huang Lin Geng School of Materials Science and Engineering Harbin Institute of TechnologyHarbin 150001China Waikato Centre for Advanced Materials and Manufacturing School of EngineeringUniversity of WaikatoHamilton 3240New Zealand State Key Laboratory of Advanced Welding and Joining Harbin Institute of TechnologyHarbin 150001China

Discontinuously reinforced titanium matrix composites(DRTMCs)with a network structure have been extensively researched due to their superior combination of strength and ***,their fatigue performance has remained *** order to elucidate the fatigue behavior of DRTMCs,a tension-tension fatigue test was performed on a TiB/nearα-Ti composite with network *** results showed that the variability of fatigue lifetime increased as the stress level *** analysis indicated that fatigue crack initiation was associated with facet formation,while the subsequent propagation was hindered by the network structure comprising TiB whiskers and *** characterization further revealed that facets formed due to a combination of shear and normal *** reduction in fatigue lifetime was attributed to an increase in the effective slip length,which was influenced by the orientation of grains near the crack-initiation sites toward basal slip in the life-limiting *** in situ observation suggested that the crack initiation was facilitated by both basal and prismatic slip ofα-Ti as well as fracture of *** propagation was found to be associated with basal and prismatic slip systems with high Schmid factors,regardless of whether the crack was intergranular or intragranular.

关键词： Titanium matrix composite TiBw Fatigue lifetime variability Crack initiation Crack propagation

Selective leaching of calcium from mechanically activated mixed rare earth concentrate

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Journal of Rare Earths 2024年第6期42卷 1149-1156,I0006页

作者： Jiang Liu Bingxue Chen Yuanqi Feng Yijun Cao Yukun huang Yuan Shi meng Li Zhongyuan Critical Metals Laboratory School of Chemical EngineeringZhengzhou UniversityZhengzhou450001China State Key Laboratory of Advanced Processing and Recycling of Nonferrous Metals Lanzhou University of TechnologyLanzhou730050China

The loss of rare earths(REs)takes place during the pre-decalcification process of mixed rare earth *** an effort to reduce such RE loss,a novel idea to improve the leaching selectivity of Ca to REs by applying selective mechanical activation was ***,regarding the key minerals affecting the leaching selectivity of Ca to REs,the differences in the mechanical activation behaviors of CaF_(2) and REFCO_(3) were studied,and we find that the lattice strain of CaF_(2) increases from 0.21%to 0.42%,whereas that of REFCO_(3) increases from 0.31%to 0.40%.Notably,CaF_(2) demonstrates a larger lattice strain than REFCO_(3),indicating greater mechanical activation energy storage and higher leaching ***,the HCl leaching process was studied.A significant leaching selectivity of Ca to REs,from 21.6 to 35.1,is achieved through mechanical *** Ca leaching rate reaches 80.7%when the RE loss is 2.3%in the activated *** study provides an novel approach for achieving selective extraction of specific components via mechanical activation pretreatment.

关键词： Mixed rare earth concentrate Pre-decalcification Selective mechanical activation Selective leaching

Perception-Driven Learning of High-Dynamic Jumping Motions for Single-Legged Robots

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Journal of Bionic Engineering 2024年第4期21卷 1733-1746页

作者： Nengxiang Sun Fei meng Sai Gu Botao Liu Xuechao Chen Zhangguo Yu Qiang huang School of Mechatronical Engineering Beijing Institute of TechnologyBeijing100081China Key Laboratory of Biomimetic Robots and Systems Ministry of EducationBeijing100081China

Legged robots show great potential for high-dynamic motions in continuous interaction with the physical environment,yet achieving animal-like agility remains significant *** animals usually predict and plan their next locomotion by combining high-dimensional information from proprioception and exteroception,and adjust the stiffness of the body’s skeletal muscle system to adapt to the current *** control methods have limitations in handling high-dimensional state information or complex robot motion that are difficult to plan manually,and Deep Reinforcement Learning(DRL)algorithms provide new solutions to robot motioncontrol *** by biomimetics theory,we propose a perception-driven high-dynamic jump adaptive learning algorithm by combining DRL algorithms with Virtual Model Control(VMC)*** robot will be fully trained in simulation to explore its motion potential by learning the factors related to continuous jumping while knowing its real-time jumping *** policy trained in simulation is successfully deployed on the bio-inspired single-legged robot testing platform without further *** results show that the robot can achieve continuous and ideal vertical jumping motion through simple training.

关键词： Deep reinforcement learning High-dynamic jump Perception driven Single-legged robot

Simulation and reconstruction of particle trajectories in the CEPC drift chamber

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Nuclear Science and Techniques 2024年第8期35卷 9-22页

作者： meng‑Yao Liu Wei‑Dong Li Xing‑Tao huang Yao Zhang Tao Lin Ye Yuan Institute of Frontier and Interdisciplinary Science Shandong UniversityQingdao 266237China Institute of High Energy Physics Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China

The circular electron-positron collider(CEPC)is designed to precisely measure the properties of the Higgs boson,study electroweak interactions at the Z-boson peak,and search for new physics beyond the Standard *** a component of the 4th conceptual CEPC detector,the drift chamber facilitates the measurement of charged *** study implemented a Geant4-based simulation and track reconstruction for the drift *** the simulation,detector construction and response were implemented and added to the CEPC simulation *** development of track reconstruction involves track finding using the combinatorial Kalman filter method and track fitting using the tool of *** the simulated data,the tracking performance was *** results showed that both the reconstruction resolution and tracking efficiency satisfied the requirements of the CEPC experiment.

关键词： CEPC Drift chamber Detector simulation Track reconstruction

Damaged apple detection with a hybrid YOLOv3 algorithm

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Information Processing in Agriculture 2024年第2期11卷 163-171页

作者： meng Zhang Huazhao Liang Zhongju Wang Long Wang Chao huang Xiong Luo Schoolof Computer and Communication Engineering University of Science and Technoogy BejingBejing 1083China lShunde Innovation SchoolUniversity of Science and Technology BeijingFoshan 528399China

This paper proposes an improved You Only Look Once(YOLOv3)algorithm for automatically detecting damaged apples to promote the automation of the fruit processing *** the proposed method,a clustering method based on Rao-1 algorithm is introduced to optimize anchor box *** clustering method uses the intersection over the union to form the objective function and the most representative anchor boxes are generated for normal and damaged apple *** verify the feasibility and effectiveness of the proposed method,real apple images collected from the Internet are *** with the generic YOLOv3 and Fast Region-based Convolutional Neural Network(Fast R-CNN)algorithms,the proposed method yields the highest mean average precision value for the test ***,it is practical to apply the proposed method for intelligent apple detection and classification tasks.

关键词： Rao algorithm Apple detection Clustering Smart agriculture