检索结果-南通市图书馆

Hyperspectral Image Based Interpretable Feature Clustering Algorithm

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第5期79卷 2151-2168页

作者： Yaming Kang PeishunYe Yuxiu Bai Shi Qiu School of Information Engineering Yulin UniversityYulin719000China key laboratory of Spectral imaging Technology CAS Xi’an Institute of Optics and Precision MechanicsChinese Academy of SciencesXi’an710119China

Hyperspectral imagery encompasses spectral and spatial dimensions,reflecting the material properties of *** application proves crucial in search and rescue,concealed target identification,and crop growth *** is an important method of hyperspectral *** vast data volume of hyperspectral imagery,coupled with redundant information,poses significant challenges in swiftly and accurately extracting features for subsequent *** current hyperspectral feature clustering methods,which are mostly studied from space or spectrum,do not have strong interpretability,resulting in poor comprehensibility of the ***,this research introduces a feature clustering algorithm for hyperspectral imagery from an interpretability *** commences with a simulated perception process,proposing an interpretable band selection algorithm to reduce data *** this,amulti-dimensional clustering algorithm,rooted in fuzzy and kernel clustering,is developed to highlight intra-class similarities and inter-class *** optimized P systemis then introduced to enhance computational *** system coordinates all cells within a mapping space to compute optimal cluster centers,facilitating parallel *** approach diminishes sensitivity to initial cluster centers and augments global search capabilities,thus preventing entrapment in local minima and enhancing clustering *** conducted on 300 datasets,comprising both real and simulated *** results show that the average accuracy(ACC)of the proposed algorithm is 0.86 and the combination measure(CM)is 0.81.

关键词： Hyperspectral fuzzy clustering tissue P system band selection interpretable

Physics-informed deep learning for fringe pattern analysis

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Opto-Electronic Advances 2024年第1期7卷 4-15页

作者： Wei Yin Yuxuan Che xinsheng Li Mingyu Li Yan Hu Shijie Feng Edmund Y.Lam Qian Chen Chao Zuo Smart computational imaging laboratory(SCILab) School of Electronic and Optical EngineeringNanjing University of Science and TechnologyNanjing 210094China Smart computational imaging Research Institute(SCIRI)of Nanjing University of Science and Technology Nanjing 210019China Jiangsu key laboratory of Spectral imaging&Intelligent Sense Nanjing 210094China Department of Electrical and Electronic Engineering The University of Hong KongPokfulamHong Kong SAR 999077China

Recently,deep learning has yielded transformative success across optics and photonics,especially in optical *** neural networks (DNNs) with a fully convolutional architecture (e.g.,U-Net and its derivatives) have been widely implemented in an end-to-end manner to accomplish various optical metrology tasks,such as fringe denoising,phase unwrapping,and fringe ***,the task of training a DNN to accurately identify an image-to-image transform from massive input and output data pairs seems at best naive,as the physical laws governing the image formation or other domain expertise pertaining to the measurement have not yet been fully exploited in current deep learning *** this end,we introduce a physics-informed deep learning method for fringe pattern analysis (PI-FPA) to overcome this limit by integrating a lightweight DNN with a learning-enhanced Fourier transform profilometry (Le FTP) *** parameterizing conventional phase retrieval methods,the Le FTP module embeds the prior knowledge in the network structure and the loss function to directly provide reliable phase results for new types of samples,while circumventing the requirement of collecting a large amount of high-quality data in supervised learning *** by the initial phase from Le FTP,the phase recovery ability of the lightweight DNN is enhanced to further improve the phase accuracy at a low computational cost compared with existing end-to-end *** results demonstrate that PI-FPA enables more accurate and computationally efficient single-shot phase retrieval,exhibiting its excellent generalization to various unseen objects during *** proposed PI-FPA presents that challenging issues in optical metrology can be potentially overcome through the synergy of physics-priors-based traditional tools and data-driven learning approaches,opening new avenues to achieve fast and accurate single-shot 3D imaging.

关键词： optical metrology deep learning physics-informed neural networks fringe analysis phase retrieval

Implementation of integrated nonlocal sensing for object shape and rotational speed

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2024年第7期67卷 6-12页

作者： Zhenyu Guo Yunlong Wang Zehong Chang Jiawei Wang Junliang Jia Pei Zhang Ministry of Education key laboratory for Nonequilibrium Synthesis and Modulation of Condensed Matter Shaanxi Province Key Laboratory of Quantum Information and Quantum Optoelectronic DevicesSchool of PhysicsXi’an Jiaotong UniversityXi’an 710049China

The expeditious acquisition of information pertaining to objects through the utilization of quantum technology has been a perennial issue of *** far,the efficient utilization of information from dynamic objects with limited resources remains a significant ***,we realize a nonlocal integrated sensing of the object's amplitude and phase information by combining digital spiral imaging with the correlated orbital angular momentum *** amplitude information is utilized for object identification,while the phase information enables us to determine the rotational *** demonstrate the nonlocal identification of a rotating object's shape,irrespective of its rotational symmetry,and introduce the concept of the correlated rotational Doppler effect,establishing a fundamental connection between this effect and the classical rotational Doppler effect,i.e.,that both rely on extracting crucial information from the spiral spectrum of *** present study highlights a promising pathway towards the realization of quantum remote sensing and imaging.

关键词： digital spiral imaging orbital angular momentum correlated rotational Doppler effect

Short-term prediction for chaotic time series based on photonic reservoir computing using VCSEL with a feedback loop

在线全文

学校读者我要写书评

暂无评论

Photonics Research 2024年第6期12卷 1222-1230页

作者： xiNGxiNG GUO HANXU ZHOU SHUIYING xiANG QIAN YU YAHUI ZHANG YANAN HAN TAO WANG YUE HAO State key laboratory of Integrated Service Networks Xidian UniversityXi'an 710071China State key Discipline laboratory of Wide Bandgap Semiconductor Technology School of MicroelectronicsXidian UniversityXi'an 710071China

Chaos,occurring in a deterministic system,has permeated various fields such as mathematics,physics,and life ***,the prediction of chaotic time series has received widespread attention and made signifi-cant ***,many problems,such as high computational complexity and difficulty in hardware im-plementation,could not be solved by existing *** overcome the problems,we employ the chaotic system of a vertical-cavity surface-emitting laser(VCSEL)mutual coupling network to generate chaotic time series through optical system simulation and experimentation in this ***,a photonic reservoir com-puting based on VCSEL,along with a feedback loop,is proposed for the short-term prediction of the chaotic time *** relationship between the prediction difficulty of the reservoir computing(RC)system and the differ-ence in complexity of the chaotic time series has been studied with ***,the attention coefficient of injection strength and feedback strength,prediction duration,and other factors on system perfor-mance are considered in both simulation and *** use of the RC system to predict the chaotic time series generated by actual chaotic systems is significant for expanding the practical application scenarios of the RC.

关键词： loop chaotic prediction

Thermal-contact capacity of one-dimensional attractive Gaudin-Yang model

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第4期33卷 231-235页

作者：张小敏程颂陈洋洋 Institute of Modern Physics Northwest UniversityXi'an 710069China Beijing computational Science Research Center Beijing 100193China Peng Huanwu Center for Fundamental Theory Northwest UniversityXi'an 710069China Shaanxi key laboratory for Theoretical Physics Frontiers Northwest UniversityXi'an 710069China

Tan's contact C is an important quantity measuring the two-body correlations at short distances in a dilute *** we make use of the technique of exactly solved models to study the thermal-contact capacity K_(T),i.e.,the derivative of C with respect to temperature in the attractive Gaudin-Yang *** is found that K_(T) is useful in identifying the low temperature phase diagram,and using the obtained analytical expression of K_(T),we study its critical behavior and the scaling ***,we show K_(T) versus temperature and thus the non-monotonic tendency of C in a tiny interval,for both spin-balanced and imbalanced *** a phenomenon is merely observed in multi-component systems such as SU(2)Fermi gases and spinor bosons,indicating the crossover from the Tomonaga-Luttinger liquid to the spin-coherent liquid.

关键词： Tan's Contact Gaudin-Yang model Bethe ansatz

Optimized Mask-RCNN model for particle chain segmentation based on improved online ferrograph sensor

在线全文

学校读者我要写书评

暂无评论

Friction 2024年第6期12卷 1194-1213页

作者： Shuo WANG Miao WAN Tonghai WU Zichen BAI Kunpeng WANG key laboratory of Education Ministry for Modern Design and Rotor-Bearing System Xi’an Jiaotong UniversityXi’an 710049China

Ferrograph-based wear debris analysis(WDA)provides significant information for wear fault analysis of mechanical *** decades of offline application,this conventional technology is being driven by the online ferrograph sensor for real-time wear state ***,online ferrography has been greatly limited by the low imaging quality and segmentation accuracy of particle chains when analyzing degraded lubricant oils in practical *** address this issue,an integrated optimization method is developed that focuses on two aspects:the structural re-design of the online ferrograph sensor and the intelligent segmentation of particle *** enhancing the imaging quality of wear particles,the magnetic pole of the online ferrograph sensor is optimized to enable the imaging system directly observe wear particles without penetrating ***,a light source simulation model is established based on the light intensity distribution theory,and the LED installation parameters are determined for particle illumination uniformity in the online ferrograph *** this basis,a Mask-RCNN-based segmentation model of particle chains is constructed by specifically establishing the region of interest(ROI)generation layer and the ROI align layer for the irregular particle *** these measures,a new online ferrograph sensor is designed to enhance the image acquisition and information extraction of wear *** verification,the developed sensor is tested to collect particle images from different degraded oils,and the images are further handled with the Mask-RCNN-based model for particle feature *** results reveal that the optimized online ferrography can capture clear particle images even in highly-degraded lubricant oils,and the illumination uniformity reaches 90%in its imaging *** importantly,the statistical accuracy of wear particles has been improved from 67.2%to 94.1%.

关键词： wear particle analysis online ferrography particle image acquisition particle chain segmentation

Regulating the dopant clustering in LiZnAs-based diluted magnetic semiconductor

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Physics B 2024年第5期33卷 617-623页

作者：贾子航周波姜振益张小东 Institute of Modern Physics Northwest UniversityXi'an 710069China Shaanxi key laboratory for Theoretical Physics Frontiers Northwest UniversityXi'an 710069China Department of Physics Chinese University of Hong KongHong Kong SARChina Beijing computational Science Research Center Beijing 100193China

Tuning of the magnetic interaction plays the vital role in reducing the clustering of magnetic dopant in diluted magnetic semiconductors(DMS).Due to the not well understood magnetic mechanism and the interplay between different magnetic mechanisms,no efficient and universal tuning strategy is proposed at ***,the magnetic interactions and formation energies of isovalent-doped(Mn) and aliovalent(Cr)-doped LiZnAs are studied based on density functional theory(DFT).It is found that the dopant–dopant distance-dependent magnetic interaction is highly sensitive to the carrier concentration and carrier type and can only be explained by the interplay between two magnetic mechanisms,i.e.,superexchange and Zener’s p–d exchange ***,the magnetic behavior and clustering of magnetic dopant can be tuned by the interplay between two magnetic *** insensitivity of the tuning effect to U parameter suggests that our strategy could be universal to other DMS.

关键词： diluted magnetic semiconductor dopant distribution first-principles calculations

Metal–organic framework wafer enabled fast response radiation detection with ultra-low dark current

在线全文

学校读者我要写书评

暂无评论

Nano Research 2024年第4期17卷 2988-2993页

作者： Meng Xu Jianxi Liu Wei Wu Yang Chen Donghao Ma Sixin Chen Wanqi Jie Menghua Zhu Yadong Xu State key laboratory of Solidification Processing MIIT Key Laboratory of Radiation Detection Materials and Devices&School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China

Semiconductive metal–organic frameworks(MOFs)have attracted great interest for the electronic ***,dark currents of present hybrid organic–inorganic materials are 1000–10,000 times higher than those of commercial inorganic detectors,leading to poor charge ***,we demonstrate a ZIF-8(Zn(mim)_(2),mim=2-methylimidazolate)wafer with ultra-low dark current of 1.27 pA·mm^(-2) under high electric fields of 322 V·mm^(-1).The isostatic pressing preparation process provides ZIF-8 wafers with good ***,the presence of redox-active metals and small spatial separation between components promotes the charge *** ZIF-8-based semiconductor detector shows promising X-ray detection sensitivity of 70.82μC·Gy^(-1)·cm^(-2) with low doses exposures,contributing to superior X-ray imaging capability with a relatively high spatial resolution of 1.2 lp·mm^(-1).Simultaneously,good peak discrimination with the energy resolution of~43.78%is disclosed when the detector is illuminated by uncollimated 241Am@5.48 MeVα-*** results provide a broad prospect of MOFs for future radiation detection applications.

关键词： MOFs lead-free α-particles X-ray detection and imaging dark current fast response

Perturbed low-thrust geostationary orbit transfer guidance via polynomial costate estimation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Chinese Journal of Aeronautics 2024年第3期37卷 181-193页

作者： Zhao LI Hengnian LI Fanghua JIANG Junfeng LI State key laboratory of Astronautic Dynamics Xi’an Satellite Control CenterXi’an 710043China School of Aerospace Engineering Tsinghua UniversityBeijing 100084China

This paper proposes an optimal,robust,and efficient guidance scheme for the perturbed minimum-time low-thrust transfer toward the geostationary *** Earth’s oblateness perturbation and shadow are taken into *** is difficult for a Lyapunov-based or trajectory-tracking guidance method to possess multiple characteristics at the same time,including high guidance optimality,robustness,and onboard computational *** this work,a concise relationship between the minimum-time transfer problem with orbital averaging and its optimal solution is identified,which reveals that the five averaged initial costates that dominate the optimal thrust direction can be approximately determined by only four initial modified equinoctial orbit elements after a coordinate *** on this relationship,the optimal averaged trajectories constituting the training dataset are randomly generated around a nominal averaged *** polynomial regression models are trained on the training dataset and are regarded as the costate *** the transfer,the spacecraft can obtain the real-time approximate optimal thrust direction by combining the costate estimations provided by the estimators with the current state at any ***,all these computations onboard are *** simulation results show that the proposed guidance scheme possesses extremely high guidance optimality,robustness,and onboard computational efficiency.

关键词： Low thrust Orbital transfer Trajectory optimization Guidance Indirect method Orbital averaging Machine learning Geostationary satellites