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Three-channel CMOS transimpedance amplifier for LidAr sensor receiver

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Journal of Systems Engineering and Electronics 2024年第1期35卷 74-80页

作者： LIU ruqing ZHU Jingguo JIANG Yan LI Feng JIANG Chenghao MENG Zhe Photoelectric r&d Center Academy of Opto-ElectronicsChinese Academy of SciencesBeijing 100094China

For time-of-flight(TOF)light detection and ranging(LidAr),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(rGC)as the input stage is at the core of the complementary metal oxide semiconductor(CMOS)circuit chip,giving it more immunity to input photodiode detectors.A simple smart output interface acting as a feedback structure,which is rarely found in other designs,reduces the chip size and power consumption *** circuit is designed using a 0.5μm CMOS process technology to achieve low *** device delivers a 33.87 dB?transimpedance gain at 350 *** a higher input load capacitance,it shows a-3 dB bandwidth of 461 MHz,indicating a better detector tolerance at the front end of the *** a 3.3 V supply voltage,the device consumes 5.2 mW,and the total chip area with three channels is 402.8×597.0μm2(including the test pads).

关键词： transimpedance amplifier(TIA) three-channel regulated cascade(rGC) light detection and ranging(LidAr)

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Electro-optic 3d snapshot of a laser wakefield accelerated kilo-ampere electron bunch

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Light(Science & Applications) 2024年第5期13卷 823-834页

作者： Kai Huang Zhan Jin Nobuhiko Nakanii Tomonao Hosokai Masaki Kando Kansai Institute for Photon Science(KPSI) National Institutes for Quantum Science and Technology(QST)KyotoJapan. Laser Accelerator r&d Innovative Light Sources DivisionRIKEN SPring-8 CenterHyogoJapan. SANKEN Osaka UniversityOsakaJapan

Laser wakefield acceleration,as an advanced accelerator concept,has attracted great attentions for its ultrahigh acceleration gradient and the capability to produce high brightness electron *** three-dimensional(3d)density serves as an evaluation metric for the particle bunch quality and is intrinsically related to the applications of an *** its significance,this parameter has not been experimentally measured in the investigation of laser wakefield *** report on an electro-optic 3d snapshot of a laser wakefield electron bunch at a position outside the *** 3d shape of the electron bunch was detected by simultaneously performing optical transition radiation imaging and electro-optic *** 3d structures to a few micrometer levels were reconstructed using a genetic *** electron bunch possessed a transverse size of less than 30 *** current profile shows a multi-peak *** main peak had a duration ofd a peak current>1 *** maximum electron 3d number density was~9×10^(21)m^(-3).This research demonstrates a feasible way of 3d density monitoring on femtosecond kilo-ampere electron bunches,at any position of a beam transport line for relevant applications.

关键词： laser acceleration field

development and performance evaluation of high temperature resistant strong adsorption rigid blocking agent

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Petroleum Science 2024年第4期21卷 2650-2662页

作者： Zhe Xu Jin-Sheng Sun Jing-Ping Liu Kai-He Lv Xiao-dong dong Zong-Lun Wang Tai-Feng Zhang Yuan-Wei Sun Zhi-Wen dai School of Petroleum Engineering China University of Petroleum (East China) CNPC Engineering Technology r&d Company Limited

As drilling wells continue to move into deep ultra-deep layers, the requirements for temperature resistance of drilling fluid treatments are getting higher and higher. Among them, blocking agent, as one of the key treatment agents, has also become a hot spot of research. In this study, a high temperature resistant strong adsorption rigid blocking agent(QW-1) was prepared using KH570 modified silica,acrylamide(AM) and allyltrimethylammonium chloride(TMAAC). QW-1 has good thermal stability,average particle size of 1.46 μm, water contact angle of 10.5., has a strong hydrophilicity, can be well dispersed in water. The experimental results showed that when 2 wt% QW-1 was added to recipe A(4 wt% bentonite slurry+0.5 wt% dSP-1(filtration loss depressant)), the API filtration loss decreased from 7.8to 6.4 m L. After aging at 240.C, the API loss of filtration was reduced from 21 to 14 m L, which has certain performance of high temperature loss of filtration. At the same time, it is effective in sealing 80-100mesh and 100-120 mesh sand beds as well as 3 and 5 μm ceramic sand discs. Under the same conditions,the blocking performance was superior to silica(5 μm) and calcium carbonate(2.6 μm). In addition, the mechanism of action of QW-1 was further investigated. The results show that QW-1 with amide and quaternary ammonium groups on the molecular chain can be adsorbed onto the surface of clay particles through hydrogen bonding and electrostatic interaction to form a dense blocking layer, thus preventing further intrusion of drilling fluid into the formation.

关键词： High adsorption rigid microsphere High temperature resistance Blocking performance

A new type of lipophilic hydrophobic self-repairing cellulose insulating paper developed with ST-110/FAS/PTFE ternary system as coating substrate

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High Voltage 2024年第2期9卷 474-483页

作者： Zhenglin Zeng Jinshan Qin Zuhao Wang Weimin Tan Chao Tang College of Engineering and Technology Southwest UniversityChongqingChina International r&d Center for New Technologies of Smart Grid and Equipment ChongqingChina

The moisture generated by the ageing of the oil-paper insulating system can easily lead to the deterioration of the performance of the insulating *** order to alleviate the impact of moisture on the performance of the insulating paper,we developed a kind of lipophilic hydrophobic self-repairing cellulose insulating paper(new insulating paper)based on the ternary system of polytetrafluoroethylene,fluorocarbon surfactant and fluorinated alkyl silane,and accelerated thermal ageing test for 45 days at 130°C was carried *** experimental results show that the new insulating paper with excellent lipophilic property can realise hydrophobic self-repairing through heat treatment after physical *** tensile strength and elongation at break of the new insulating paper increased by 5%–8%and 6.25%–27%respectively compared with the original cellulose insulating *** the end of ageing,the relative dielectric constant and dielectric loss factor of new insulating paper are 10.4%and 9.9%lower than that of the original cel-lulose insulating paper,while the breakdown voltage is 6.8%*** acid and moisture content produced during the ageing process of the insulating oil impregnated with new insulating paper are also less,indicating that the coating can delay the ageing of the insulating paper.

关键词： coating moisture cellulose

Activation redistribution Based Hybrid Asymmetric Quantization Method of Neural Networks

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工程与科学中的计算机建模(英文) 2024年第1期138卷 981-1000页

作者： Lu Wei Zhong Ma Chaojie Yang r&d Innovation Center Xi’an Microelectronics Technology InstituteXi’an710065China

The demand for adopting neural networks in resource-constrained embedded devices is continuously *** is one of the most promising solutions to reduce computational cost and memory storage on embedded *** order to reduce the complexity and overhead of deploying neural networks on Integeronly hardware,most current quantization methods use a symmetric quantization mapping strategy to quantize a floating-point neural network into an integer ***,although symmetric quantization has the advantage of easier implementation,it is sub-optimal for cases where the range could be skewed and not *** often comes at the cost of lower *** paper proposed an activation redistribution-based hybrid asymmetric quantizationmethod for neural *** proposedmethod takes data distribution into consideration and can resolve the contradiction between the quantization accuracy and the ease of implementation,balance the trade-off between clipping range and quantization resolution,and thus improve the accuracy of the quantized neural *** experimental results indicate that the accuracy of the proposed method is 2.02%and 5.52%higher than the traditional symmetric quantization method for classification and detection tasks,*** proposed method paves the way for computationally intensive neural network models to be deployed on devices with limited computing *** will be available on https://***/ycjcy/Hybrid-Asymmetric-Quantization.

关键词： Quantization neural network hybrid asymmetric accuracy

Effect of ellagitannin metabolites ellagic acid and urolithins A-d on the non-enzymatic glycation of human serum albumin and inhibiting mechanisms

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Food Science and Human Wellness 2024年

作者： Lu Zhang Chun-yan Peng Wen-na Zhou Fei-yan Lu Lin-ju Xu Qing-hui Wen Xing Xie Zong-cai Tu National r&d Center of Freshwater Fish Processing， College of Life Science， Jiangxi Normal University State Key Laboratory of Food Science and resources， Nanchang University

Effect of ellagitannins gut microbiota metabolites ellagic acid (EA) and urolithin A-urolithin d (UroA-Urod) on human serum albumin (HSA) glycation were firstly evaluated in this research. The inhibition mechanisms were investigated by methylglyoxal (MGO) trapping and radical scavenging ability assays， docking studies and Nano LC-Orbitrap-MS/MS technology. results indicated that the inhibition of urolithins on HSA glycation was highly positive correlated with the number of phenolic hydroxy groups. Addition of Urod and EA could effectively enhance the content of free amino group， suppress dicarbonyl compounds and advanced glycation end-products (AGEs) formation， alleviated tryptophan and protein oxidation， inhibited HSA amyloid-like aggregation. They could also trap MGO and scavenge dPPH· and ABTS·+. Molecular docking indicated that EA and UroA-Urod interact with HSA mainly through hydrogen bound and hydrophobic interaction， among which two or three hydrogen bonds were formed. The number of glycation sites were reduced from 11 to 10， 10， 7， and 10， respectively， when 90 μmol/L of EA， UroA， UroC and Urod were added. However， weak inhibition was observed on UroA and UroB. These findings can provide scientific evidence for the application of ellagitannins-rich foods in alleviating diabetic complications.

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LdAS&ET-Ad:Learnable distillation Attack Strategies and Evolvable Teachers Adversarial distillation

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Computers, Materials & Continua 2024年第5期79卷 2331-2359页

作者： Shuyi Li Hongchao Hu Xiaohan Yang Guozhen Cheng Wenyan Liu Wei Guo National digital Switching System Engineering&Technological r&d Center The PLA Information Engineering UniversityZhengzhou450000China

Adversarial distillation(Ad)has emerged as a potential solution to tackle the challenging optimization problem of loss with hard labels in adversarial ***,fixed sample-agnostic and student-egocentric attack strategies are unsuitable for ***,the reliability of guidance from static teachers diminishes as target models become more *** paper proposes an Ad method called Learnable distillation Attack Strategies and Evolvable Teachers Adversarial distillation(LdAS&ET-Ad).Firstly,a learnable distillation attack strategies generating mechanism is developed to automatically generate sample-dependent attack strategies tailored for distillation.A strategy model is introduced to produce attack strategies that enable adversarial examples(AEs)to be created in areas where the target model significantly diverges from the teachers by competing with the target model in minimizing or maximizing the Ad ***,a teacher evolution strategy is introduced to enhance the reliability and effectiveness of knowledge in improving the generalization performance of the target *** calculating the experimentally updated target model’s validation performance on both clean samples and AEs,the impact of distillation from each training sample and AE on the target model’s generalization and robustness abilities is assessed to serve as feedback to fine-tune standard and robust teachers *** evaluate the performance of LdAS&ET-Ad against different adversarial attacks on the CIFAr-10 and CIFAr-100 *** experimental results demonstrate that the proposed method achieves a robust precision of 45.39%and 42.63%against AutoAttack(AA)on the CIFAr-10 dataset for resNet-18 and MobileNet-V2,respectively,marking an improvement of 2.31%and 3.49%over the baseline *** comparison to state-of-the-art adversarial defense techniques,our method surpasses Introspective Adversarial distillation,the top-performing method in terms of robustne

关键词： Adversarial training adversarial distillation learnable distillation attack strategies teacher evolution strategy

Hierarchical model updating for high-speed maglev vehicle/guideway coupled system based on multiobjective optimization

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Frontiers of Structural and Civil Engineering 2024年第5期18卷 788-804页

作者： dexiang Li Jingyu Huang College of Civil Engineering Tongji UniversityShanghai 200092China National Maglev Transportation Engineering r&d Center Tongji UniversityShanghai 201804China

The high-speed maglev vehicle/guideway coupled model is an essential simulation tool for investigating vehicle dynamics and mitigating coupled *** improve its accuracy efficiently,this study investigated a hierarchical model updating method integrated with field ***,a high-speed maglev vehicle/guideway coupled model,taking into account the real effect of guideway material properties and elastic restraint of bearings,was developed by integrating the finite element method,multi-body dynamics,and electromagnetic levitation ***,simultaneous in-site measurements of the vehicle/guideway were conducted on a high-speed maglev test line to analyze the system response and structural modal *** the hierarchical updating,an Elman neural network with the optimal Latin hypercube sampling method was used to substitute the FE guideway model,thus improving the computational *** multi-objective particle swarm optimization algorithm with the gray relational projection method was applied to hierarchically update the parameters of the guideway layer and magnetic force layer based on the measured modal parameters and the electromagnet vibration,***,the updated coupled model was compared with the field measurements,and the results demonstrated the model’s accuracy in simulating the actual dynamic response,validating the effectiveness of the updating method.

关键词： high-speed maglev vehicle/guideway coupled model field measurement model updating neural network multi-objective optimization

Friction and wear performance of polyether ether ketone(PEEK)polymers in three lubrication regimes

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Friction 2024年第4期12卷 670-682页

作者： davide MASSOCCHI Nora LECIS Marco LATTUAdA davide SCAGLIA Steven CHATTErTON Paolo PENNACCHI department of Mechanical Engineering Politecnico di MilanoMilan 20156Italy Eni SpA Downstream product R&DLombardia 20097Italy Eurobearings S.r.L. Lombardia 29016Italy

This experimental study investigates the friction and wear of three coatings commonly used in industrial applications,particularly in hydrodynamic *** three materials under investigation were Babbitt,polyether ether ketone(PEEK)reinforced with 15%carbon fibers,and PEEK reinforced with 20%carbon *** first polymer material was extruded,while the other was produced by fused deposition modelling(FdM).The materials were subjected to sliding tests in a pin-on-disc configuration,with a steel ball serving as the counter *** tests were conducted at room temperature,with a load of 10 N and under three different lubrication conditions:dry,grease,and *** linear speed was set at 0.3 m/s for the dry and semi-solid lubrication tests,while for the oil tests,the speed was set at 0.25 m/*** greases used had consistency grades of NGLI 000 and NGLI *** ISO VG 68 circulation oil was used for the oil lubrication ***,thermodynamic analyses were performed under the most severe conditions(i.e.,dry)to investigate the steel-Babbitt and steel-PEEK contact.

关键词： hydrodynamic bearings polyether ether ketone(PEEK)polymers additive manufacturing grease lubrication sliding oil lubrication ball-on-disk tribology