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Experimental and numerical flutter analysis of a folding fin with multiple asymmetric free-plays

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Chinese Journal of Aeronautics 2024年第5期37卷 332-348页

作者： Chenyu LIU Chao AN Changchuan XIE xin zhang Lan YANG School of Aeronautic Science and Engineering Beihang UniversityBeijing 100191China Beijing Institute of Electronic System Engineering Beijing 100854China Beijing Institute of Astronautical Systems Engineering Beijing 100076China

Experimental folding fin models with an adjustable free-play are tested in a wind *** fin structure is modeled using the free-interface component mode synthesis method,and its free-play is modeled as four independent nonlinear springs with asymmetric stiffness.A nonplanar unsteady vortex-lattice method considering compressibility is employed to address nonlinear deformation and high subsonic *** spline interpolation is improved through projection and *** aeroelastic characteristics of folding fins with different free-play magnitudes,initial conditions and elastic-axis positions are analyzed using an established time-marching method because of its relatively small computation scale and high *** results show good consistency among the presented method,the wind tunnel test and the harmonic balance *** is a negative correlation between the critical speed of divergent motion and the ratio of the initial condition to the free-play *** either the free-play magnitude or the initial condition is extreme(tiny or vast),the system nonlinearity degenerates to ***,the flutter prevention design of a linear model can be applied to a nonlinear model,such as moving the elastic-axis position *** presented fin configuration exhibits an unstable limit cycle oscillation because the orders of coupled flutter modes do not change with variations in equivalent linear stiffness.

关键词： Free-play Limit cycle oscillation Flutter Component mode synthesis Vortex-lattice method

Threshold Selection and Resource Allocation for Quantized Identification

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Journal of Systems Science & Complexity 2024年第1期37卷 204-229页

作者： WANG Ying LI xin ZHAO Yanlong zhang Ji-Feng Key Laboratory of Systems and Control Institute of Systems ScienceAcademy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190China School of Mathematical Sciences University of Chinese Academy of SciencesBeijing 100049China

This paper is concerned with the optimal threshold selection and resource allocation problems of quantized identification, whose aims are improving identification efficiency under limited resources. Firstly, the first-order asymptotically optimal quantized identification theory is extended to the weak persistent excitation condition. Secondly, the characteristics of time and space complexities are established based on the Cramér-Rao lower bound of quantized systems. On these basis, the optimal selection methods of fixed thresholds and adaptive thresholds are established under aperiodic signals, which answer how to achieve the best efficiency of quantized identification under the same time and space complexity. In addition, based on the principle of maximizing the identification efficiency under a given resource, the optimal resource allocation methods of quantized identification are given for the cases of fixed thresholds and adaptive thresholds, respectively, which show how to balance time and space complexity to realize the best identification efficiency of quantized identification.

关键词： Quantized output resource allocation system identification threshold selection.

GP‐FMLNet:A feature matrix learning network enhanced by glyph and phonetic information for Chinese sentiment analysis

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CAAI Transactions on Intelligence Technology 2024年第4期9卷 960-972页

作者： Jing Li Dezheng zhang Yonghong Xie Aziguli Wulamu yao zhang School of Computer and Communication Engineering University of Science and Technology BeijingBeijingChina Beijing Key Laboratory of Knowledge Engineering for Materials Science University of Science and Technology BeijingBeijingChina University of Alberta EdmontonAlbertaCanada

Sentiment analysis is a fine‐grained analysis task that aims to identify the sentiment polarity of a specified *** methods in Chinese sentiment analysis tasks only consider sentiment features from a single pole and scale and thus cannot fully exploit and utilise sentiment feature information,making their performance less than *** resolve the problem,the authors propose a new method,GP‐FMLNet,that integrates both glyph and phonetic information and design a novel feature matrix learning process for phonetic features with which to model words that have the same pinyin information but different glyph *** method solves the problem of misspelling words influencing sentiment polarity prediction ***,the authors iteratively mine character,glyph,and pinyin features from the input comments ***,the authors use soft attention and matrix compound modules to model the phonetic features,which empowers their model to keep on zeroing in on the dynamic‐setting words in various positions and to dispense with the impacts of the deceptive‐setting ***-periments on six public datasets prove that the proposed model fully utilises the glyph and phonetic information and improves on the performance of existing Chinese senti-ment analysis algorithms.

关键词： aspect‐level sentiment analysis deep learning feature extraction glyph and phonetic feature matrix compound learning

Configuration Synthesis and Grasping Performance Analysis of Multi-Loop Coupling Capture Mechanism for Launch and Recovery of Torpedo-Shaped Autonomous Underwater Vehicle

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China Ocean Engineering 2024年第3期38卷 453-466页

作者： zhang Guo-xing XIA xin-lu GUO Jin-wei School of Mechanical Engineering Jiangsu University of Science and TechnologyZhenjiang 212100China

Research of capture mechanisms with strong capture adaptability and stable grasp is important to solve the problem of launch and recovery of torpedo-shaped autonomous underwater vehicles(AUVs).A multi-loop coupling capture mechanism with strong adaptability and high retraction rate has been proposed for the launch and recovery of torpedo-shaped AUVs with different morphological ***,the principle of capturing motion retraction is described based on the appearance characteristics of torpedo-shaped AUVs,and the configuration synthesis of the capture mechanism is carried out using the method of constrained chain ***,the screw theory is employed to analyze the degree of freedom(DoF)of the capture ***,the 3D model of the capture mechanism is established,and the kinematics and dynamics simulations are carried *** with the capture orientation requirements of the capture mechanism,the statics and vibration characteristics analyses are carried ***,considering the capture process and the underwater working environment,the motion characteristics and hydraulics characteristics of the capture mechanism are ***,a principle prototype is developed and the torpedo-shaped AUVs capture experiment is *** work provides technical reserves for the research and development of AUV capture special equipment.

关键词： capture mechanism torpedo-shaped AUVs configuration synthesis launch and recovery grasping performance analysis

Emergence of machine language: towards symbolic intelligence with neural networks

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National Science Review 2024年第4期11卷 27-30页

作者： Yuqi Wang Xu-yao zhang Cheng-Lin Liu Tieniu Tan Zhaoxiang zhang State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of Sciences

Representation learning is a core issue in artificial intelligence (AI). Currently,there exists a disparity in the choice of representation between humans and machines. Humans rely on discrete language for communicati...

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Rotating magnetic field inhibits Aβ protein aggregation and alleviates cognitive impairment in Alzheimer’s disease mice

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Zoological Research 2024年第4期45卷 924-936页

作者： Ruo-Wen Guo Wen-Jing Xie Biao Yu Chao Song xin-Miao Ji xin-Yu Wang Mei zhang xin zhang High Magnetic Field Laboratory CAS Key Laboratory of High Magnetic Field and Ion Beam Physical BiologyHefei Institutes of Physical ScienceChinese Academy of SciencesHefeiAnhui 230031China Science Island Branch of Graduate School University of Science and Technology of ChinaHefeiAnhui 230036China Institutes of Physical Science and Information Technology Anhui UniversityHefeiAnhui 230601China School of Life Sciences Division of Life Sciences and MedicineUniversity of Science and Technology of ChinaHefeiAnhui 230026China

Amyloid beta(Aβ)monomers aggregate to form fibrils and amyloid plaques,which are critical mechanisms in the pathogenesis of Alzheimer’s disease(AD).Given the important role of Aβ1-42 aggregation in plaque formation,leading to brain lesions and cognitive impairment,numerous studies have aimed to reduce Aβaggregation and slow AD *** diphenylalanine(FF)sequence is critical for amyloid aggregation,and magnetic fields can affect peptide alignment due to the diamagnetic anisotropy of aromatic *** this study,we examined the effects of a moderate-intensity rotating magnetic field(RMF)on Aβaggregation and AD *** indicated that the RMF directly inhibited Aβamyloid fibril formation and reduced Aβ-induced cytotoxicity in neural cells in *** the AD mouse model APP/PS1,RMF restored motor abilities to healthy control levels and significantly alleviated cognitive impairments,including exploration and spatial and non-spatial memory *** examinations demonstrated that RMF reduced amyloid plaque accumulation,attenuated microglial activation,and reduced oxidative stress in the APP/PS1 mouse *** findings suggest that RMF holds considerable potential as a non-invasive,high-penetration physical approach for AD treatment.

关键词： lzheimer’s disease Rotating magnetic field Amyloid-β Cognitive function Alzheimer’s disease animal models

Unified Classification and Rejection:A One-versus-all Framework

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Machine Intelligence Research 2024年第5期21卷 870-887页

作者： Zhen Cheng Xu-yao zhang Cheng-Lin Liu State Key Laboratory of Multimodal Artificial Intelligence Systems Institute of AutomationChinese Academy of SciencesBeijing100190China School of Artificial Intelligence University of Chinese Academy of SciencesBeijing100049China

Classifying patterns of known classes and rejecting ambiguous and novel(also called as out-of-distribution(OOD))inputs are involved in open world pattern *** neural network models usually excel in closed-set classification while perform poorly in rejecting OOD *** tackle this problem,numerous methods have been designed to perform open set recognition(OSR)or OOD rejection/detection *** methods mostly take post-training score transformation or hybrid models to ensure low scores on OOD inputs while separating known *** this paper,we attempt to build a unified framework for building open set classifiers for both classification and OOD *** formulate the open set recognition of K-known-class as a(K+1)-class classification problem with model trained on known-class samples *** decomposing the K-class problem into K one-versus-all(OVA)binary classification tasks and binding some parameters,we show that combining the scores of OVA classifiers can give(K+1)-class posterior probabilities,which enables classification and OOD rejection in a unified *** maintain the closed-set classification accuracy of the OVA trained classifier,we propose a hybrid training strategy combining OVA loss and multi-class cross-entropy *** implement the OVA framework and hybrid training strategy on the recently proposed convolutional prototype network and prototype classifier on vision transformer(ViT)*** on popular OSR and OOD detection datasets demonstrate that the proposed framework,using a single multi-class classifier,yields competitive performance in closed-set classification,OOD detection,and misclassification *** code is available at https://***/zhen-cheng121/CPN_OVA_unified.

关键词： Open set recognition out-of-distribution detection misclassification detection convolutional prototype network oneversus-all Dempster-Shafer theory of evidence

Hemorrhagic cystitis in gastric cancer after nanoparticle albuminbound paclitaxel:A case report

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 1084-1090页

作者： xin-Jie zhang Jian Lou Department of Cancer Center The Fifth Affiliated Hospital of Wenzhou Medical UniversityLishui 323000Zhejiang ProvinceChina

BACKGROUND The advanced first-line regimen for advanced gastric cancer is based on a combination of fluoropyrimidine and platinum and/or paclitaxel(PTX),forming a two-or three-drug *** to conventional PTX,nanoparticle albumin-bound PTX(Nab-PTX)has better therapeutic effects and fewer adverse effects reported in ***-PTX is a great option for patients presenting with advanced gastric ***,we highlight an adverse event(hemorrhagic cystitis)of Nab-PTX in advanced gastric *** SUMMARY A 55-year-old male was diagnosed with lymph node metastasis after a laparo-scopic-assisted radical gastrectomy for gastric cancer that was treated by Nab-PTX and S-1(AS).On the 15th day after treatment with AS,he was diagnosed with hemorrhagic *** Physicians should be aware that hemorrhagic cystitis is a potential adverse event associated with Nab-PTX treatment.

关键词： Nanoparticle albumin-bound paclitaxel Hemorrhagic cystitis Gastric cancer Adverse event Case report

Taiji-TianQin-LISA network:Precisely measuring the Hubble constant using both bright and dark sirens

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Science China(Physics,Mechanics & Astronomy) 2024年第2期67卷 59-77页

作者： Shang-Jie Jin Ye-Zhu zhang Ji-Yu Song Jing-Fei zhang xin zhang Key Laboratory of Cosmology and Astrophysics(Liaoning)&College of Sciences Northeastern UniversityShenyang 110819China Key Laboratory of Data Analytics and Optimization for Smart Industry(Ministry of Education) Northeastern UniversityShenyang 110819China National Frontiers Science Center for Industrial Intelligence and Systems Optimization Northeastern UniversityShenyang 110819China

In the coming decades,the space-based gravitational-wave(GW)detectors such as Taiji,TianQin,and LISA are expected to form a network capable of detecting millihertz GWs emitted by the mergers of massive black hole binaries(MBHBs).In this work,we investigate the potential of GW standard sirens from the Taiji-TianQin-LISA network in constraining cosmological *** the optimistic scenario in which electromagnetic(EM)counterparts can be detected,we predict the number of detectable bright sirens based on three different MBHB population models,i.e.,popⅢ,Q3d,and *** results show that the TaijiTianQin-LISA network alone could achieve a constraint precision of 0.9%for the Hubble constant,meeting the standard of precision ***,the Taiji-TianQin-LISA network could effectively break the cosmological parameter degeneracies generated by the CMB data,particularly in the dynamical dark energy *** combined with the CMB data,the joint CMB+Taiji-TianQin-LISA data offerσ(w)=0.036 in the wCDM model,which is close to the latest constraint result obtained from the CMB+SN *** also consider a conservative scenario in which EM counterparts are not *** to the precise sky localizations of MBHBs by the Taiji-TianQin-LISA network,the constraint precision of the Hubble constant is expected to reach 1.2%.In conclusion,the GW standard sirens from the Taiji-TianQin-LISA network will play a critical role in helping solve the Hubble tension and shedding light on the nature of dark energy.

关键词： space-based gravitational wave detection standard sirens the Taiji-TianQin-LISA network the Hubble constant dark energy