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A physics-informed deep learning framework for spacecraft pursuit-evasion task assessment

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Chinese Journal of Aeronautics 2024年第5期37卷 363-376页

作者： Fuyunxiang yang Leping yang Yanwei ZHU College of Aerospace Science and Engineering National University of Defense TechnologyChangsha 410073China

Qualitative spacecraft pursuit-evasion problem which focuses on feasibility is rarely studied because of high-dimensional dynamics,intractable terminal constraints and heavy computational *** this paper,A physics-informed framework is proposed for the problem,providing an intuitive method for spacecraft threat relationship determination,situation assessment,mission feasibility analysis and orbital game rules *** the first time,situation adjustment suggestions can be provided for the weak player in orbital ***,a dimension-reduction dynamics is derived in the line-of-sight rotation coordinate system and the qualitative model is determined,reducing complexity and avoiding the difficulty of target set presentation caused by individual ***,the Backwards Reachable Set(BRS)of the target set is used for state space partition and capture zone ***-time analysis can eliminate the influence of changeable initial state and enable the proposed framework to analyze plural situations ***,a time-dependent Hamilton-Jacobi-Isaacs(HJI)Partial Differential Equation(PDE)is established to describe BRS evolution driven by dimension-reduction dynamics,based on level set ***,Physics-Informed Neural Networks(PINNs)are extended to HJI PDE final value problem,supporting orbital game rules summarization through capture zone evolution ***,numerical results demonstrate the feasibility and efficiency of the proposed framework.

关键词： Spacecraft pursuit-evasion Qualitative differential game Physics-Informed Neural Networks(PINNs) Reachability analysis Hamilton-Jacobi-Isaacs(HJI) Partial Differential Equations(PDEs)

Connecting cellular mechanisms and extracellular vesicle cargo in traumatic brain injury

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Neural Regeneration Research 2024年第10期19卷 2119-2131页

作者： Nikita Ollen-Bittle Austyn D.Roseborough Wenxuan Wang jeng-liang D.Wu Shawn N.Whitehead Department of Anatomy and Cell Biology Western UniversityLondonONCanada Schulich School of Medicine and Dentistry Western UniversityLondonONCanada Deparment of Clinical Neurological Sciences Western UniversityLondonONCanada

Traumatic brain injury is followed by a cascade of dynamic and complex events occurring at the cellular level. These events include: diffuse axonal injury, neuronal cell death, blood-brain barrier break down, glial activation and neuroinflammation, edema, ischemia, vascular injury, energy failure, and peripheral immune cell infiltration. The timing of these events post injury has been linked to injury severity and functional outcome. Extracellular vesicles are membrane bound secretory vesicles that contain markers and cargo pertaining to their cell of origin and can cross the blood-brain barrier. These qualities make extracellular vesicles intriguing candidates for a liquid biopsy into the pathophysiologic changes occurring at the cellular level post traumatic brain injury. Herein, we review the most commonly reported cargo changes in extracellular vesicles from clinical traumatic brain injury samples. We then use knowledge from animal and in vitro models to help infer what these changes may indicate regrading cellular responses post traumatic brain injury. Future research should prioritize labeling extracellular vesicles with markers for distinct cell types across a range of timepoints post traumatic brain injury.

关键词： axonal injury biomarkers blood-brain barrier chronic traumatic encephalopathy extracellular vesicles glial activation neuroinflammation traumatic brain injury

Processing,microstructure,and properties of porous ceramic composites with directional channels

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Journal of Materials Science & Technology 2024年第1期168卷 1-15页

作者： Bo Zhang yang yang Xueling Fan Key Laboratory of Service Performance and Protection Technology in Extreme Environments Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory for Strength and Vibration of Mechanical Structures School of Aerospace EngineeringXi’an Jiaotong UniversityXi’an 710049China

Porous ceramic composites with directional microchannels from micrometer to dozens of micrometer levels have attracted more and more attention in various fields including aerospace,biomedicines,and thermal insulation due to their excellent fluid permeability,mechanical properties,*** this article,we summarize the recent directional porous ceramics developments including their main processing routes and respective ***,the properties get from different processing routes have been com-pared and analyzed in terms of microstructures,mechanical properties,and *** has been given to the deeper understanding which can allow one to control the microstructural features of these porous ceramic composites to obtain the desired *** work can provide a useful reference for the development and application of porous ceramic composites with directional microchan-nels.

关键词： Porous ceramic composites Directional microchannels Processing routes Permeability

Chinese herbal medicine decreases incidence of hepatocellular carcinoma in diabetes mellitus patients with regular insulin management

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World Journal of Gastrointestinal Oncology 2024年第3期16卷 716-731页

作者： Hsiang-Chun Lai Ju-Chien Cheng Hei-Tung Yip Long-Bin jeng Sheng-Teng Huang Graduate Institute of Chinese Medicine School of Chinese MedicineCollege of Chinese MedicineChina Medical UniversityTaichung 404328TaiwanChina Department of Medical Laboratory Science and Biotechnology China Medical UniversityTaichung 404TaiwanChina Management Office for Health Data China Medical University HospitalTaichung 404327TaiwanChina Organ Transplantation Center China Medical University HospitalTaichung 40447TaiwanChina Department of Chinese Medicine China Medical University HospitalSchool of Chinese MedicineChina Medical UniversityTaichung 40447TaiwanChina

BACKGROUND Type 2 diabetes mellitus(DM)is an independent risk factor for hepatocellular carcinoma(HCC),while insulin is a potent *** a new therapeutic modality for preventing insulin users from developing HCC is a critical goal for *** To investigate whether regular herbal medicine use can decrease HCC risk in DM patients with regular insulin *** We used data acquired from the Taiwan,Chinaese National Health Insurance research database between 2000 and *** identified patients with DM who were prescribed insulin for>3 *** herb user group was further defined as patients prescribed herbal medication for DM for>3 months per annum during RESULTS We initially enrolled 657144 DM patients with regular insulin use from 2000 to *** these,46849 patients had used a herbal treatment for DM,and 140547 patients were included as the matched control *** baseline variables were similar between the herb users and *** patients with regular herb use had a 12%decreased risk of HCC compared with the control group[adjusted hazard ratio(aHR)=0.88,95%CI=0.80–0.97].The cumulative incidence of HCC in the herb users was significantly lower than that of the *** with a herb use of>5 years cumulatively exhibited a protective effect against development of HCC(aHR=0.82,P<0.05).Of patients who developed HCC,herb users exhibited a longer survival time than nonusers(aHR=0.78,P=0.0001).Additionally,we report the top 10 herbs and formulas in prescriptions and summarize the potential pharmacological effects of the *** analysis indicated that Astragalus propinquus(Huang Qi)plus Salvia miltiorrhiza Bunge(Dan Shen),and Astragalus propinquus(Huang Qi)plus Trichosanthes kirilowii Maxim.(Tian Hua Fen)were the most frequent combination of single ***,Ji Sheng Shen Qi Wan plus Dan Shen was the most frequent combination of herbs and *** This large-scale retrospective cohort study reveals th

关键词： Hepatocellular carcinoma Diabetes mellitus Insulin Herb Taiwan,Chinaese National health insurance research database

New Second-Level-Discrete Zeroing Neural Network for Solving Dynamic Linear System

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1521-1523页

作者： Min yang School of Robotics Hunan UniversityChangsha 410082China

Dear Editor,This letter deals with a new second-level-discretization method with higher precision than the traditional first-level-discretization ***,the traditional discretization method utilizes the first-order time derivative information,and it is termed first-level-discretization *** contrast,the new discretization method not only utilizes the first-order time derivative information,but also makes use of the second-order derivative *** combining the new second-level-discretization method with zeroing neural network(ZNN),the second-level-discrete ZNN(SLDZNN)model is proposed to solve dynamic(i.e.,time-variant or time-dependent)linear *** experiments and application to angle-of-arrival(AoA)localization show the effectiveness and superiority of the SLDZNN model.

关键词： method derivative utilize

Alignment efficient image-sentence retrieval considering transferable cross-modal representation learning

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Frontiers of Computer Science 2024年第1期18卷 77-91页

作者： yang yang Jinyi GUO Guangyu LI Lanyu LI Wenjie LI Jian yang School of Computer Science and Engineering Nanjing University of Science and TechnologyNanjing 210094China Department of Computing Hong Kong Polytechnic UniversityHong Kong 100872China State Key Lab.for Novel Software Technology Nanjing UniversityNanjing 210094China 14th Research Institute of China Electronics Technology Group Corporation Nanjing 210094China guangyu.li2017@***

Traditional image-sentence cross-modal retrieval methods usually aim to learn consistent representations of heterogeneous modalities,thereby to search similar instances in one modality according to the query from another modality in *** basic assumption behind these methods is that parallel multi-modal data(i.e.,different modalities of the same example are aligned)can be obtained in *** other words,the image-sentence cross-modal retrieval task is a supervised task with the alignments as ***,in many real-world applications,it is difficult to realign a large amount of parallel data for new scenarios due to the substantial labor costs,leading the non-parallel multi-modal data and existing methods cannot be used *** the other hand,there actually exists auxiliary parallel multi-modal data with similar semantics,which can assist the non-parallel data to learn the consistent ***,in this paper,we aim at“Alignment Efficient Image-Sentence Retrieval”(AEIR),which recurs to the auxiliary parallel image-sentence data as the source domain data,and takes the non-parallel data as the target domain *** single-modal transfer learning,AEIR learns consistent image-sentence cross-modal representations of target domain by transferring the alignments of existing parallel ***,AEIR learns the image-sentence consistent representations in source domain with parallel data,while transferring the alignment knowledge across domains by jointly optimizing a novel designed cross-domain cross-modal metric learning based constraint with intra-modal domain adversarial ***,we can effectively learn the consistent representations for target domain considering both the structure and semantic ***,extensive experiments on different transfer scenarios validate that AEIR can achieve better retrieval results comparing with the baselines.

关键词： image-sentence retrieval transfer learning semantic transfer structure transfer

Light touch in quantum:an interview with *** Haroche

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Advanced Photonics 2024年第1期6卷 10-16页

作者： Chao-yang Lu CAS Centre for Excellence in Quantum Information and Quantum Physics HefeiChina NYU Shanghai NYU-ECNU Institute of PhysicsShanghaiChina University of Science and Technology of China Department of Modern PhysicsShanghaiChina

Lu:Hello,***,nice to see you again!Let us start the *** 2012,you and David Wineland won the Nobel Prize in *** you describe your work in simple terms to a general audience?And can you tell us how you were originally interested in this field and got into this study?Haroche:Maybe I should start with the second part of the question.I got interested in atomic physics when I was a student atÉcole Normale Supérieure(ENS)in Paris in the 1960s.

关键词： quantum interview Serge

Fixed-Time Sliding Mode Control With Varying Exponent Coefficient for Modular Reconfigurable Flight Arrays

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IEEE/CAA Journal of Automatica Sinica 2024年第2期11卷 514-528页

作者： Jianquan yang Chunxi yang Xiufeng Zhang Jing Na Faculty of Mechanical and Electrical Engineering Kunming University of Science and TechnologyKunming 650500 Yunnan International Joint Laboratory of Intelligent Control and Aoolication of Advanced Equipment Kunming 650500China IEEE

The modular system can change its physical structure by self-assembly and self-disassembly between modules to dynamically adapt to task and environmental requirements. Recognizing the adaptive capability of modular systems, we introduce a modular reconfigurable flight array(MRFA) to pursue a multifunction aircraft fitting for diverse tasks and requirements,and investigate the attitude control and the control allocation problem by using the modular reconfigurable flight array as a platform. First, considering the variable and irregular topological configuration of the modular array, a center-of-mass-independent flight array dynamics model is proposed to allow control allocation under over-actuated situations. Secondly, in order to meet the stable, fast and accurate attitude tracking performance of the MRFA, a fixed-time convergent sliding mode controller with state-dependent variable exponent coefficients is proposed to ensure fast convergence rate both away from and near the system equilibrium point without encountering the singularity. It is shown that the controller also has fixed-time convergent characteristics even in the presence of external disturbances. Finally,simulation results are provided to demonstrate the effectiveness of the proposed modeling and control strategies.

关键词： Control allocation dynamic model fixed-time stabilization modular reconfigurable flight array(MRFA) sliding mode

Smoothed particle hydrodynamics based numerical study of hydroplaning considering permeability characteristics of runway surface

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Frontiers of Structural and Civil Engineering 2024年第3期18卷 319-333页

作者： yang yang Xingyi ZHU Denis JELAGIN Alvaro GUARIN Key Laboratory of Road and Traffic Engineering of Ministry of Education Tongji UniversityShanghai 200092China Auto Engineering Research Institute BYD Auto Industry Company LimitedShenzhen 518118China Department of Civil and Architectural Engineering KTH Royal Institute of TechnologyStockholm 10044Sweden

The presence of water films on a runway surface presents a risk to the landing of *** tire of the aircraft is separated from the runway due to a hydrodynamic force exerted through the water film,a phenomenon called *** a lot of numerical investigations into hydroplaning have been conducted,only a few have considered the impact of the runway ***,computational problems,such as excessive distortion and computing efficiency decay,may arise with such numerical models when dealing with the thin water *** paper presents a numerical model comprising of the tire,water film,and the interaction with the runway,applying a mathematical model using the smoothed particle hydrodynamics and finite element(SPH-FE)*** material properties and geometric features of the tire model were included in the model framework and water film thicknesses from 0.75 mm to 7.5 mm were used in the numerical ***,this work investigated the impacts of both surface texture and the runway *** interaction between tire rubber and the rough runway was analyzed in terms of frictional force between the two *** SPH-FE model was validated with an empirical equation proposed by the National Aeronautics and Space Administration(NASA).Then the computational efficiency of the model was compared with the traditional coupled Eulerian-Lagrangian(CEL)*** on the SPH-FE model,four types of the runway(Flat,SMA-13,AC-13,and OGFC-13)were *** simulation of the asphalt runway shows that the SMA-13,AC-13,and OGFC-13 do not present a hydroplaning risk when the runway permeability coefficient exceeds 6%.

关键词： SPH-FE approach hydroplaning numerical simulation surface texture runway surface reconstruction