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***’S EQUATION AND ITS LIMITATION

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Applied Mathematics and Mechanics(English Edition) 1982年第6期3卷 827-832页

作者：白哲 wuha Huazhong university of Science and Technology

The problem of p-n junction in Ref.[1] is discussed in *** consider that Tsai Shu-tang’s view that ***-ley’s equation cannot be applied to all circumstances is cor-rect,but we cannot sag,because of this,that ***’smethod of treatment and its conclusion for p-n junction *** this paper we demonstrated that ***’s e-quation merely describes ideal p-n junction model.

关键词： W.SHOCKLEY S EQUATION AND ITS LIMITATION

Frequency Synthesizer of Short-Wave SFH/MFSK System

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wuhan university Journal of Natural Sciences 1998年第1期3卷 71-75页

作者： Gan Liangcai, Bao Yongqiang(College of Electronic Information, wuha university, wuhan 430072, China) wuha university College of Electronic Information Wuhan China

The technology of DDS-driven PLL is introduced and a new scheme of frequency synthesizer which is suitable for SW SFH/MFSK System is presented in this paper. Based on the special requirement of SW communication, a model of the scheme is given and the results show that the frequency synthesizer has small frequency insteval (≤0.1 Hz), short switch pierod (<200 ms) and high frequency stability as crystal oseillator.

关键词： Key words frequency synthesizer frequency inteval switch pierod FH communication

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Direct Measurement of Light Speed Reduction in a Rubidium Vapour Medium Coherently Prepared by Electromagnetically Induced Transparency

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Chinese Physics Letters 2003年第11期20卷 1954-1956页

作者：王谨江开军何明李可仲嘉琪詹明生涂鲜花 StateKeyLaboratoryofMagneticResonanceandAtomicandMolecularPhysics WuhanInstituteofPhysicsandMathematicsChineseAcademyofSciencesWuhan430071MathematicsChineseAcademyofSciencesWuha

We have experimentally observed the reduction of light speed in a rubidium vapour medium coherently prepared by electromagnetically induced transparency. The light speed reduction was deduced by directly measuring the time delay of a probe light when it passed through the medium. The time delay varies with the intensity of the coupling laser, and the typical time delay we recorded was 1.8μs, corresponding to a light speed of 56000m/s.

关键词： Time delay

ON THE CRITERION FOR THE ABSOLUTE STABILITY OF THE CONTROL SYSTEM

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Applied Mathematics and Mechanics(English Edition) 1982年第2期3卷 267-279页

作者：廖晓昕 wuha Huazhong Teachers College

In this paper,firstly we give the criterion for the absolutestability of the second canonical form for the control system,*** equation of the longitudinal motions of a plane as aparticular *** corresponding result in[8],[9]is a par-ticular example given in this ***,we give the criteriafor the absolute stability of the first canonical form in the usualcase and in the critical ***,we give some criteria forthe absolute stability of the general form for the direct *** the results in this paper merelg depend upon the relationsbetween the parameters of the system itself to give an explicit al-gebraic discriminant.

关键词： ON THE CRITERION FOR THE ABSOLUTE STABILITY OF THE CONTROL SYSTEM

A Novel Disturbance Observer Based Fixed-Time Sliding Mode Control for Robotic Manipulators With Global Fast Convergence

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IEEE/CAA Journal of Automatica Sinica 2024年第3期11卷 661-672页

作者： Dan Zhang Jiabin Hu Jun Cheng Zheng-Guang Wu Huaicheng Yan IEEE Zhejiang university of Technology Guangxi Normal university Zhejiang university the East China university of Science and Technology

This paper proposes a new global fixed-time sliding mode control strategy for the trajectory tracking control of uncertain robotic ***,a fixed-time disturbance observer(FTDO) is designed to deal with the adverse effects of model uncertainties and external disturbances in the manipulator *** an adaptive scheme is used and the adaptive FTDO(AFTDO) is developed,so that the priori knowledge of the lumped disturbance is not ***,a new non-singular fast terminal sliding mode(NFTSM) surface is designed by using an arctan function,which helps to overcome the singularity problem and enhance the robustness of the *** on the estimation of the lumped disturbance by the AFTDO,a fixed-time non-singular fast terminal sliding mode controller(FTNFTSMC)is developed to guarantee the trajectory tracking errors converge to zero within a fixed *** settling time is independent of the initial state of the *** addition,the stability of the AFTDO and FTNFTSMC is strictly proved by using Lyapunov ***,the fixed-time NFESM(FTNFTSM) algorithm is validated on a 2-link manipulator and comparisons with other existing sliding mode controllers(SMCs) are *** comparative results confirm that the FTNFTSMC has superior control performance.

关键词： Disturbance observer(DO) fixed-time non-singular sliding mode control robotic manipulator trajectory tracking

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Synthetic brochosomes:Design,synthesis,and applications

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Nano Research 2024年第2期17卷 734-742页

作者： Lin Wang Jinsol Choi Tak-Sing Wong Department of Mechanical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA Materials Research Institute The Pennsylvania State UniversityUniversity ParkPA 16802USA Department of Biomedical Engineering The Pennsylvania State UniversityUniversity ParkPA 16802USA

Brochosomes,which are nanoscopic buckyball-shaped granules produced by leafhoppers,are one of the most intricate structures discovered in *** functions of brochosomes have been proposed but only a few have been experimentally validated due to the challenge of fabricating their synthetic *** in micro-and nanofabrication have recently led to the emergence of synthetic brochosomes,opening up new possibilities for innovative *** review explores the early discovery of natural brochosomes and their geometrical features,followed by the recent progress in fabricating synthetic brochosomes and their *** on future applications and challenges in the scalable manufacturing of synthetic brochosomes are discussed.

关键词： synthetic brochosomes leafhopper antireflection superhydrophobicity surface-enhanced Raman scattering photocatalyst energy harvesting

Analysis of synthetic parameters for coating aluminum powders with phenyltriethoxysilane coupling agent and their effects on powder flow behavior

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Particuology 2024年第7期90卷 412-417页

作者： Lillian M.Mawby Bellamarie Ludwig Benjamin J.Lear Department of Chemistry The Pennsylvania State UniversityUniversity ParkPA16802USA Applied Research Laboratory The Pennsylvania State UniversityUniversity ParkPA16802USA

Though silanization of aluminum powder is currently used to improve its flow properties,for use as an alternative fuel source,there are a wide range of experimental parameters for the process and not all of them have been thoroughly *** this is complete,it is unknown if the process is optimized in terms of time,efficiency,and ***,we report on a study into the effects of changes in humidity,degree of agitation,reaction temperature,and curing time upon the deposition of phenyl triethoxysilane into 20μm(d50)aluminum *** confirm the deposition of the coating via diffuse reflectance infrared spectroscopy and x-ray photoelectron *** then characterize the coated particles using apparent density measurements and Carney flow *** analysis of variance,we find that,of the parameters explored,only changes in cure time and reaction temperature provide meaningful changes to the apparent density,while none of our parameters produced statistically significant changes in Carney flow ***,we conclude that,when optimizing silanization of aluminum particles,environmental control of humidity is unneeded and that the reaction can be run with minimal *** ability to largely ignore these parameters is a benefit to large-scale processing.

关键词： Aluminum powder Silane Fluidization Apparent density Carney flow

Lithium Sulfur Batteries:Insights from Solvation Chemistry to Feasibility Designing Strategies for Practical Applications

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Energy & Environmental Materials 2024年第4期7卷 5-27页

作者： Jian Tan Longli Ma Yuan Wang Pengshu Yi Chuming Ye Zhan Fang Zhiheng Li Mingxin Ye Jianfeng Shen Institute of Special Materials and Technology Fudan University Department of Materials Science Fudan University Department of Chemistry Fudan University

Rechargeable lithium-sulfur (Li-S) batteries,featuring high energy density,low cost,and environmental friendliness,have been dubbed as one of the most promising candidates to replace current commercial rechargeable Li-ion ***,their practical deployment has long been plagued by the infamous"shuttle effect"of soluble Li polysulfides (LiPSs) and the rampant growth of Li dendrites.

关键词： characterization tools design strategies Li–S batteries practical applications solvation chemistry

Transfer learning from T1-weighted to T2-weighted Magnetic resonance sequences for brain image segmentation

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CAAI Transactions on Intelligence Technology 2024年第1期9卷 26-39页

作者： Imene Mecheter Maysam Abbod Habib Zaidi Abbes Amira Brunel university LondonUK Geneva university Hospital GenevaSwitzerland Geneva university GenevaSwitzerland university of Groningen GroningenNetherlands university of Southern Denmark OdenseDenmark university of Sharjah SharjahUAE De Montfort university LeicesterUK

Magnetic resonance(MR)imaging is a widely employed medical imaging technique that produces detailed anatomical images of the human *** segmentation of MR im-ages plays a crucial role in medical image analysis,as it enables accurate diagnosis,treatment planning,and monitoring of various diseases and *** to the lack of sufficient medical images,it is challenging to achieve an accurate segmentation,especially with the application of deep learning *** aim of this work is to study transfer learning from T1-weighted(T1-w)to T2-weighted(T2-w)MR sequences to enhance bone segmentation with minimal required computation *** the use of an excitation-based convolutional neural networks,four transfer learning mechanisms are proposed:transfer learning without fine tuning,open fine tuning,conservative fine tuning,and hybrid transfer ***,a multi-parametric segmentation model is proposed using T2-w MR as an intensity-based augmentation *** novelty of this work emerges in the hybrid transfer learning approach that overcomes the overfitting issue and preserves the features of both modalities with minimal computation time and *** segmentation results are evaluated using 14 clinical 3D brain MR and CT *** results reveal that hybrid transfer learning is superior for bone segmentation in terms of performance and computation time with DSCs of 0.5393±*** T2-w-based augmentation has no significant impact on the performance of T1-w MR segmentation,it helps in improving T2-w MR segmentation and developing a multi-sequences segmentation model.

关键词： computer vision convolution image segmentation learning(artificial intelligence)