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Ground threat prediction-based path planning of unmanned autonomous helicopter using hybrid enhanced artificial bee colony algorithm

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Defence Technology（防务技术） 2024年第2期32卷 1-22页

作者： Zengliang han mou Chen Haojie Zhu Qingxian Wu School of Automation Engineering Nanjing University of Aeronautics and AstronauticsNanjing 211106China

Unmanned autonomous helicopter(UAH)path planning problem is an important component of the UAH mission planning *** to reduce the influence of non-complete ground threat information on UAH path planning,a ground threat prediction-based path planning method is proposed based on artificial bee colony(ABC)algorithm by collaborative thinking ***,a dynamic threat distribution probability model is developed based on the characteristics of typical ground *** dynamic no-fly zone of the UAH is simulated and established by calculating the distribution probability of ground threats in real ***,a dynamic path planning method for UAH is designed in complex environment based on the real-time prediction of ground *** adding the collision warning mechanism to the path planning model,the flight path could be dynamically adjusted according to changing no-fly ***,a hybrid enhanced ABC algorithm is proposed based on collaborative thinking *** proposed algorithm applies the leader-member thinking mechanism to guide the direction of population evolution,and reduces the negative impact of local optimal solutions caused by collaborative learning update strategy,which makes the optimization performance of ABC algorithm more controllable and ***,simulation results verify the feasibility and effectiveness of the proposed ground threat prediction path planning method.

关键词： UAH Path planning Ground threat prediction Hybrid enhanced Collaborative thinking

Track-before-detect for bistatic radar based on pseudo-spectrum

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Chinese Journal of Aeronautics 2024年第1期37卷 236-246页

作者： Tao han Gongjian zhou School of Electronics and Information Engineering Harbin Institute of TechnologyHarbin 150001China Key Laboratory of Marine Environmental Monitoring and Information Processing Ministry of Industry and Information TechnologyHarbin 150001China

Track-Before-Detect(TBD) is an efficient method to detect dim targets for radars. Conventional TBD usually follows an approximate motion model of the target, which may cause an inaccurate integration of the target energy. A TBD technique on basis of pseudo-spectrum in mixed coordinates adopting an accurate motion model for bistatic radar system is developed in this *** predicted position in bistatic polar plane is derived according to a nonlinear function that exactly describes the constant Cartesian velocity motion. Then around the predicted position, a pseudo-spectrum is formulated and its samples are accumulated to the integration frame for energy integration. The evolution of the state and the procedure of accumulation of the target energy are derived elaborately. The superior performance of the proposed method is demonstrated by some simulations.

关键词： Weak target detection Bistatic radar Track-before-detect Pseudo-spectrum Multiframe integration

Immune recovery after fluid resuscitation in rats with severe hemorrhagic shock

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2017年第5期18卷 402-409页

作者： Feng YAO Yuan-qiang LU Jiu-kun JIANG Lin-hui GU han-zhou mou Department of Emergency Medicine the First Affiliated Hospital School of Medicine Zhejiang University Cancer Institute Zhejiang Tumor Hospital

Objective： To investigate the effects of resuscitation with normal saline（NS）, hypertonic saline（HTS）, and hydroxyethyl starch（HES） on regulatory T cells（Tregs）, helper T 1（Th1）/Th2 and cytotoxic T 1（Tc1）/Tc2 profiles in the treatment of hemorrhagic shock. Methods： Rats subjected to severe hemorrhagic shock were resuscitated for 30 min with NS（n=8）, HTS（n=8）, or HES（n=8）; sham（n=8） and naive control（n=8） groups were used for comparison. Following fluid resuscitation, the whole shed blood was reinfused for 30 min, and the rats were observed with continuous hemodynamic monitoring for 120 min. CD4^＋CD25^＋Foxp3^＋ Treg proportions, Th1/Th2 and Tc1/Tc2 profiles in spleen were analyzed by three-color flow cytometry. Results： The proportion of CD4^＋CD25^＋Foxp3^＋ Tregs and ratios of Th1/Th2 and Tc1/Tc2 did not differ among control, sham, and HTS groups, but were significantly lower in NS and HES groups（both P0.05 vs. sham）; NS and HES levels were similar. The level of Tc1 was significantly increased in HTS（P0.05 vs. sham）, and levels of Tc2 were increased in NS, HES, and HTS groups compared to sham（all P0.05）, but did not differ from each other. Conclusions： HTS resuscitation has a greater impact on immune system recovery than NS or HES by preserving the proportion of Tregs and maintaining the balance between Th1/Th2 and Tc1/Tc2 cells in the spleen. Thus, HTS resuscitation provides potential immunomodulatory activity in the early stage after hemorrhagic shock.

关键词： Regulatory T cells Helper T cells Cytotoxic T cells Hemorrhagic shock

On Stability Discrimination of Limit Cycles for Piecewise Smooth Systems

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Acta Mathematica Sinica,English Series 2024年第7期40卷 1785-1803页

作者： Mao An han Xia Yu zhou School of Mathematical Sciences Zhejiang Normal UniversityJinhua321004P.R.China

This paper is concerned with the problem of stability discrimination of limit cycles for piecewise smooth *** first establish the Poincaré map near a periodic orbit,and deduce the first order derivative of the map for general piecewise smooth systems on the ***,we obtain a sufficient condition for determining the stability of limit cycles for these systems.

关键词： Piecewise smooth system limit cycle stability

Critical layer in liquid-solid system influencing the remediation of chromium using zeolite-supported sulfide nano zero-valent iron

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Journal of Environmental Sciences 2024年第1期135卷 232-241页

作者： Chundi zhou Caiyun han Nengsheng Liu Faculty of Material and Environment Guangxi University for NationalitiesNanning 530008China College of Environmental Science and Engineering Tongji UniversityShanghai 200092China Faculty of Metallurgical and Energy Engineering Kunming University of Science and TechnologyKunming 650093China

Sulfidated nano zero-valent iron particles were immobilized on ZSM-5 zeolite(Z/S-nZⅥ)and used for hexavalent chromium(Cr(Ⅵ))*** performance of Z/S-nZⅥimproved with the increase in Cr(Ⅵ)concentration(han 60 mg/*** adsorption behavior for Cr(Ⅵ)was different from that reported in previous *** improved performance can be tailored for increasing efficiency of nano zero-valent iron(nZⅥ)corrosion,while the degree of corrosion of nZⅥwas affected by the concentration of the pollutant as discussed by kinetics,X-ray diffraction(XRD)and X-ray photoelectron spectrometer(XPS)*** experiments for the dissolution of ferrous ions and the dosage of adsorbent demonstrated that the critical layer in the liquid-solid system changed with the increase in the concentration of Cr(Ⅵ)(Cr(Ⅵ):Z/S-nZⅥ>0.6).Moreover,the removal mechanisms of Cr(Ⅵ)were elucidated through XRD,transmission electron microscopy(TEM)and XPS *** results demonstrate that the species of chromium in the critical layer changed from Cr(Ⅲ)to Cr(Ⅵ)as the concentration of chromium increased from low to ***,the critical layer was composed of Cr(Ⅵ),Fe(Ⅱ),O and H ***,the experiments of coexisting ions and aging time confirmed that Z/S-nZⅥpossessed high selectivity and stability to ensure efficiency and cost-effectiveness in practical applications.

关键词： Cr(VI) Corrosion Critical layer Selectivity Stability

Long non-coding RNA H19 regulates neurogenesis of induced neural stem cells in a mouse model of closed head injury

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Neural Regeneration Research 2024年第4期19卷 872-880页

作者： mou Gao Qin Dong Zhijun Yang Dan Zou Yajuan han Zhanfeng Chen Ruxiang Xu Department of Neurosurgery Sichuan Academy of Medical Sciences and Sichuan Provincial People's HospitalSchool of MedicineUniversity of Electronic Science and Technology of China Department of Neurosurgery Chinese PLA General Hospital Zhongsai Stem Cell Genetic Engineering Co. Ltd. Department of Neurology Fu Xing HospitalCapital Medical University

Stem cell-based therapies have been proposed as a potential treatment for neural regeneration following closed head *** previously reported that induced neural stem cells exert beneficial effects on neural regeneration via cell ***,the neural regeneration efficiency of induced neural stem cells remains *** this study,we explored differentially expressed genes and long non-coding RNAs to clarify the mechanism underlying the neurogenesis of induced neural stem *** found that H19 was the most downregulated neurogenesis-associated lnc RNA in induced neural stem cells compared with induced pluripotent stem ***,we demonstrated that H19 levels in induced neural stem cells were markedly lower than those in induced pluripotent stem cells and were substantially higher than those in induced neural stem cell-derived *** predicted the target genes of H19 and discovered that H19 directly interacts with mi R-325-3p,which directly interacts with Ctbp2 in induced pluripotent stem cells and induced neural stem *** H19 or Ctbp2 impaired induced neural stem cell proliferation,and mi R-325-3p suppression restored the effect of H19 inhibition but not the effect of Ctbp2 ***,H19 silencing substantially promoted the neural differentiation of induced neural stem cells and did not induce apoptosis of induced neural stem ***,silencing H19 in induced neural stem cell grafts markedly accelerated the neurological recovery of closed head injury *** results reveal that H19 regulates the neurogenesis of induced neural stem cells.H19 inhibition may promote the neural differentiation of induced neural stem cells,which is closely associated with neurological recovery following closed head injury.

关键词： closed head injury Ctbp2 induced neural stem cell lncRNA H19 miR-325-3p neurogenesis

Experimental and numerical study on dynamic mechanical behaviors of shale under true triaxial compression at high strain rate

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International Journal of Mining Science and Technology 2024年第2期34卷 149-165页

作者： Xiaoping zhou Linyuan han Jing Bi Yundong Shou School of Civil Engineering Wuhan UniversityWuhan 430072China College of Civil Engineering Guizhou UniversityGuiyang 550025China

High-energy gas fracturing of shale is a novel,high efficacy and eco-friendly mining technique,which is a typical dynamic perturbing *** effectively extract shale gas,it is important to understand the dynamic mechanical properties of *** experiments on shale subjected to true triaxial compression at different strain rates are first conducted in this *** dynamic stress-strain curves,peak strain,peak stress and failure modes of shale are *** results of the study indicate that the intermediate principal stress and the minor principal stress have the significant influence on the dynamic mechanical behaviors,although this effect decreases as the strain rate *** characteristics of compression-shear failure primarily occur in shale subjected to triaxial compression at high strain rates,which distinguishes it from the fragmentation characteristics observed in shale under dynamic uniaxial ***,a numerical three-dimensional Split Hopkinson Pressure Bar(3D-SHPB),which is established by coupling PFC3D and FLAC3D methods,is validated to replicate the laboratory characteristics of *** dynamic mechanical characteristics of shale subjected to different confining stresses are systematically investigated by the coupling PFC3D and FLAC3D *** numerical results are in good agreement with the experimental data.

关键词： Dynamic behaviors True triaxial compression High strain rates Dynamic failure mechanism PFC3D-FLAC3D coupled method

Temporal Unfolding of Racial Ingroup Bias in Neural Responses to Perceived Dynamic Pain in Others

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Neuroscience Bulletin 2024年第2期40卷 157-170页

作者： Chenyu Pang Yuqing zhou Shihui han School of Psychological and Cognitive Sciences PKU-IDG/McGovern Institute for Brain ResearchBeijing Key Laboratory of Behavior and Mental HealthPeking UniversityBeijing 100081China CAS Key Laboratory of Behavioral Science Institute of PsychologyChinese Academy of SciencesBeijing 100101China Department of Psychology University of Chinese Academy of SciencesBeijing 100049China

In this study,we investigated how empathic neural responses unfold over time in different empathy networks when viewing same-race and other-race individuals in dynamic painful *** recorded magnetoencephalography signals from Chinese adults when viewing video clips showing a dynamic painful(or non-painful)stimulation to Asian and White models’faces to trigger painful(or neutral)*** found that perceived dynamic pain in Asian models modulated neural activities in the visual cortex at 100 ms–200 ms,in the orbitofrontal and subgenual anterior cingulate cortices at 150 ms–200 ms,in the anterior cingulate cortex around 250 ms–350 ms,and in the temporoparietal junction and middle temporal gyrus around 600 ms after video *** dynamic pain in White models modulated activities in the visual,anterior cingulate,and primary sensory cortices after 500 *** findings unraveled earlier dynamic activities in multiple neural circuits in response to same-race(vs other-race)individuals in dynamic painful situations.

关键词： Empathy Race Magnetoencephalography Dynamic pain Cingulate cortex

Black-box membership inference attacks based on shadow model

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The Journal of China Universities of Posts and Telecommunications 2024年第4期31卷 1-16页

作者： han Zhen zhou Wen'an han Xiaoxuan Wu Jie School of Computer Science Beijing University of Posts and TelecommunicationsBeijing 100876China

Membership inference attacks on machine learning models have drawn significant *** current research primarily utilizes shadow modeling techniques,which require knowledge of the target model and training data,practical scenarios involve black-box access to the target model with no available *** training data further complicate the implementation of these *** this paper,we experimentally compare common data enhancement schemes and propose a data synthesis framework based on the variational autoencoder generative adversarial network(VAE-GAN)to extend the training data for shadow ***,this paper proposes a shadow model training algorithm based on adversarial training to improve the shadow model's ability to mimic the predicted behavior of the target model when the target model's information is *** conducting attack experiments on different models under the black-box access setting,this paper verifies the effectiveness of the VAE-GAN-based data synthesis framework for improving the accuracy of membership inference ***,we verify that the shadow model,trained by using the adversarial training approach,effectively improves the degree of mimicking the predicted behavior of the target *** with existing research methods,the method proposed in this paper achieves a 2%improvement in attack accuracy and delivers better attack performance.

关键词： machine learning membership inference attack shadow model black-box model