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UAV maneuvering decision-making algorithm based on deep reinforcement learning under the guidance of expert experience

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Journal of Systems Engineering and Electronics 2024年第3期35卷 644-665页

作者： ZHAN Guang ZHANG Kun LI ke PIAO Haiyin School of Electronics and Information Northwestern Polytechnical UniversityXi’an 710072China Science and Technology on Electro-Optic Control Laboratory Luoyang 471009China

Autonomous umanned aerial vehicle(UAV) manipulation is necessary for the defense department to execute tactical missions given by commanders in the future unmanned battlefield. A large amount of research has been devoted to improving the autonomous decision-making ability of UAV in an interactive environment, where finding the optimal maneuvering decisionmaking policy became one of the key issues for enabling the intelligence of UAV. In this paper, we propose a maneuvering decision-making algorithm for autonomous air-delivery based on deep reinforcement learning under the guidance of expert experience. Specifically, we refine the guidance towards area and guidance towards specific point tasks for the air-delivery process based on the traditional air-to-surface fire control ***, we construct the UAV maneuvering decision-making model based on Markov decision processes(MDPs). Specifically, we present a reward shaping method for the guidance towards area and guidance towards specific point tasks using potential-based function and expert-guided advice. The proposed algorithm could accelerate the convergence of the maneuvering decision-making policy and increase the stability of the policy in terms of the output during the later stage of training process. The effectiveness of the proposed maneuvering decision-making policy is illustrated by the curves of training parameters and extensive experimental results for testing the trained policy.

关键词： unmanned aerial vehicle(UAV) maneuvering decision-making autonomous air-delivery deep reinforcement learning reward shaping expert experience

Influence of Human Activity Intensity on Habitat Quality in Hainan Tropical Rainforest National Park,China

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Chinese Geographical Science 2024年第3期34卷 519-532页

作者： HAN Nianlong YU Miao JIA Peihong ZHANG Yucheng HU ke School of Geography and Tourism Huizhou UniversityHuizhou 516007China School of Public Administration Hainan Uni-versityHaikou 570228China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongChina School of Geographic Sciences and Remote Sensing Guangzhou UniversityGuangzhou 510006China School of Public Administration Nanjing Agricultural UniversityNanjing 210095China

Due to long-term human activity interference,the Hainan Tropical Rainforest National Park(HTRNP)of China has experienced ecological problems such as habitat fragmentation and biodiversity loss,and with the expanding scope and intensity of human activity impact,the regional ecological security is facing serious challenges.A scientific assessment of the interrelationship between human activity intensity and habitat quality in the HTRNP is a prerequisite for achieving effective management of ecological disturbances caused by human activities and can also provide scientific strategies for the sustainable development of the *** on the land use change data in 2000,2010,and 2020,the spatial and temporal variations and the relationship between habitat quality(HQ)and human activity intensity(HAI)in the HTRNP were explored using the integrated valuation of ecosystem services and trade-offs(InVEST)*** dynamics and land use simulation models were also combined to conduct multi-scenario simulations of their *** results showed that during 2000–2020,the habitat quality of the HTRNP improved,the intensity of human activities decreased each year,and there was a negative correlation between the ***,the system dynamic model could be well coupled with the land use simulation model by combining socio-economic and natural *** simulation scenarios of the coupling model showed that the harmonious development(HD)scenario is effective in curbing the increasing trend of human activity intensity and decreasing trend of habitat quality,with a weaker trade-off between the two compared with the baseline development(BD)and investment priority oriented(IPO)*** maintain the authenticity and integrity of the HTRNP,effective measures such as ecological corridor construction,ecological restoration,and the implementation of ecological compensation policies need to be strengthened.

关键词： human activity intensity(HAI) habitat quality(HQ) bivariate spatial autocorrelation system dynamics model integrated valuation of ecosystem services and trade-offs(InVEST)model Hainan Tropical Rainforest National Park(HTRNP)of China

High-frequency magnetic properties of biphase Ce_(2)Fe_(17)N_(3)/α-Fe microflakes with easy-plane anisotropy

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Journal of Rare Earths 2024年第1期42卷 110-115,I0004页

作者： ke Wang Hang Zhang Yuandong Huang Zhibiao Xu Fashen Li Tao Wang key Laboratory for Magnetism and Magnetic Materials of MOE Lanzhou UniversityLanzhou730000China key Laboratory of Special Function Materials and Structure Design Ministry of EducationLanzhou UniversityLanzhou730000China

Soft magnetic composites(SMCs)are effective as magnetic powder cores in an *** to high saturation magnetization,large magnetocrystalline anisotropy and high operating frequency of M(metal)-RE(rear earth)soft magnetic composites,it is possible to miniaturize inductor cores by reducing total loss,especially eddy current loss and excess loss at high *** this article,the characteristics of Ce_(2)Fe_(17)N_(3)/α-Fe(CFN/F)loss per volume and effective permeability reaching a high frequency of 3 MHz are *** biphase CFN/F composite exhibits a high permeability of 16 at 70 MHz,which is two times greater than that of pure Ce_(2)Fe_(17)N_(3)(CFN)*** total loss is as low as 545 mW/cm^(3)at 3 MHz and 6 *** direct current(DC)-bias properties have a percent of permeability exceeding 65% at H=7960 A/*** phenomenon indicates that our material has a higher working frequency and lower core loss than other materials;the biphase CFN/F structure is a promising and efficient approach for developing the miniaturized radio frequency(RF)inductor core.

关键词： High frequency Soft magnetic composites Easy-plane anisotropy Permeability spectra Core loss Rare earths

GSW3.1,a novel gene controlling grain size and weight in rice

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The Crop Journal 2024年第3期12卷 796-802页

作者： Yifei Jiang Mingao Zhou Simin ke Xiaoxiao Deng Yangsheng Li State key Laboratory of Hybrid Rice Key Laboratory for Research and Utilization of Heterosis in Indica RiceMinistry of AgricultureCollege of Life SciencesWuhan UniversityWuhan 430072HubeiChina

Grain size and weight are closely related traits determining yield in rice(Oryza sativa L.).Since indica and japonica rice varieties differ significantly in multiple traits,a high-generation recombinant inbred line(RIL)population derived from the crossing LH9(indica)and RPY(japonica)was used to map grainrelated traits in six *** of the quantitative trait loci(QTL)for thousand-grain weight showed that combinations of multiple QTL significantly increased the phenotypic effect.A novel gene named GSW3.1 controlling grain size and weight was discovered using the major QTL for the colocalization of grain width and thousand-grain weight on chromosome *** editing revealed that GSW3.1(LOC_Os03g16850)was pleiotropic,positively regulating grain size and weight while affecting several other agronomic *** analysis indicated that some traits,including grain width and weight,were highly correlated with indica-japonica differentiation.

关键词： Rice Grain size and weight 3.1(GSW3.1) Quantitative trait locus Haplotype analysis

Absorption-dominant EMI shielding performance of multiple folded Bi_(2)Se_(3)/PVDF nanocomposite films

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Journal of Materiomics 2024年第1期10卷 27-36页

作者： Xinyi Pu Zunpeng Feng Siyuan Sun ke Bi Yanan Hao State key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing100876China Chinese Academy of Engineering Innovation Strategy Beijing100088China

Absorption-dominant electromagnetic interference(EMI)shielding materials are promising in reducing electromagnetic radiation pollution,but their preparation processes are usually difficult and unsuitable for large-scale *** this work,multiple folded Bi_(2)Se_(3)/PVDF nanocomposite films were fabri-cated by using a convenient tape-casting method and multiple folding,which can be easily extended in industrial *** EMI shielding effectiveness(SE)of the composite materials was investigated,which shows typical absorption-dominant behavior and can substantially reduce secondary ***,for the 35%(in volume)Bi_(2)Se_(3)/PVDF nanocomposite film,the SE_(A)of single-layered film with a thickness of 60 mm reaches 20 dB while SE_(R)is lower than 5 *** folding the film into eight layers,the SE_(A)increased to 50 dB while SE_(R)remains below 5 *** method provides an effective way to the fabrication of absorption-dominant electromagnetic absorption(EMA)and EMI shielding material.

关键词： Electromagnetic interference shielding(EMI) Electromagnetic wave absorption Bismuth selenide Composite

Effects of the inlet particle spatial distribution on the performance of a gas-solid cyclone separator

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Particuology 2024年第2期85卷 133-145页

作者： Yuge Yao Manxia Shang Xiwei ke Zhong Huang Tuo Zhou Junfu Lyu key Laboratory for Thermal Science and Power Engineering of Ministry of Education Department of Energy and Power EngineeringTsinghua UniversityBeijing100084China

The present study was aimed at the inlet particle spatial distribution of a gas-solid separator with high solid loading and investigated its effects on cyclone performance and the inner flow *** flow fields of a cyclone with different rectangular particle flow areas on the inlet surface were numerically simulated using a four-way coupling *** simulated results indicate that reducing the inlet particle flow area and lowing the inlet particle position can effectively reduce the scattered particles inside the cyclone separator and enhance the separation *** gathering the particles to the centerline can also weaken the particle *** particles near the roof account for the swirling particle ceiling *** inlet particle spatial distribution affects the pressure drop mainly by affecting the gas tangential velocity in the cylinder ***,compared to the hori-zontal particle distribution on the inlet surface,the vertical particle distribution has greater effects on cyclone performance.

关键词： Gas-solid cyclone Inlet particle spatial distribution Four-way coupling Separation efficiency Scattered particle

NCAD v1.0: a database for non-coding variant annotation and interpretation

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Journal of Genetics and Genomics 2024年第2期51卷 230-242页

作者： Xiaoshu Feng Sihan Liu ke Li Fengxiao Bu Huijun Yuan Institute of Rare Diseases West China HospitalSichuan UniversityChengduSichuan 610044China

The application of whole genome sequencing is expanding in clinical diagnostics across various genetic disorders, and the significance of non-coding variants in penetrant diseases is increasingly being demonstrated. Therefore, it is urgent to improve the diagnostic yield by exploring the pathogenic mechanisms of variants in non-coding regions. However, the interpretation of non-coding variants remains a significant challenge, due to the complex functional regulatory mechanisms of non-coding regions and the current limitations of available databases and tools. Hence, we develop the non-coding variant annotation database (NCAD, http://***/), encompassing comprehensive insights into 665,679,194 variants, regulatory elements, and element interaction details. Integrating data from 96 sources, spanning both GRCh37 and GRCh38 versions, NCAD v1.0 provides vital information to support the genetic diagnosis of non-coding variants, including allele frequencies of 12 diverse populations, with a particular focus on the population frequency information for 230,235,698 variants in 20,964 Chinese individuals. Moreover, it offers prediction scores for variant functionality, five categories of regulatory elements, and four types of non-coding RNAs. With its rich data and comprehensive coverage, NCAD serves as a valuable platform, empowering researchers and clinicians with profound insights into non-coding regulatory mechanisms while facilitating the interpretation of non-coding variants.

关键词： Non-coding variants Annotation Variant interpretation Database

In situ direct reprogramming of astrocytes to neurons via polypyrimidine tract-binding protein 1 knockdown in a mouse model of ischemic stroke

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Neural Regeneration Research 2024年第10期19卷 2240-2248页

作者： Meng Yuan Yao Tang Tianwen Huang Lining ke En Huang key Laboratory of Brain Aging and Neurodegenerative Diseases of Fujian Province Fujian Medical UniversityFuzhouFujian ProvinceChina Department of Human Anatomy School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Scientific Research Center School of Basic Medical SciencesFujian Medical UniversityFuzhouFujian ProvinceChina Department of Neurology Fujian Medical University Union HospitalFuzhouFujian ProvinceChina Fujian key Laboratory of Vascular Aging Fujian Medical UniversityFuzhouFujian ProvinceChina

In situ direct reprogramming technology can directly convert endogenous glial cells into functional neurons in vivo for central nervous system repair. Polypyrimidine tract-binding protein 1(PTB) knockdown has been shown to reprogram astrocytes to functional neurons in situ. In this study, we used AAV-PHP.e B-GFAP-sh PTB to knockdown PTB in a mouse model of ischemic stroke induced by endothelin-1, and investigated the effects of GFAP-sh PTB-mediated direct reprogramming to neurons. Our results showed that in the mouse model of ischemic stroke, PTB knockdown effectively reprogrammed GFAP-positive cells to neurons in ischemic foci, restored neural tissue structure, reduced inflammatory response, and improved behavioral function. These findings validate the effectiveness of in situ transdifferentiation of astrocytes, and suggest that the approach may be a promising strategy for stroke treatment.

关键词： astrocyte in situ direct reprogramming ischemic stroke miR-30 based shRNA neuron polypyrimidine tract-binding protein 1 transdifferentiation

Bunching enhancement for coherent harmonic generation by using phase merging effects

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Matter and Radiation at Extremes 2024年第5期9卷 10-21页

作者： ke Feng Kangnan Jiang Runshu Hu Shixia Luan Wentao Wang Ruxin Li State key Laboratory of High Field Laser Physics and CAS Center for Excellence in Ultra-intense Laser Science Shanghai Institute of Optics and Fine Mechanics(SIOM)Chinese Academy of Sciences(CAS)ShanghaiPeople’s Republic of China School of Physical Science and Technology ShanghaiTech UniversityShanghaiPeople’s Republic of China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijingPeople’s Republic of China

In this paper,promising but simple schemes are investigated to enhance the micro-bunching of relativistic electron beams for coherent harmonic generation(CHG)by using phase merging *** contrast to the standard CHG scheme,two specially designed dispersion sections(DSs)are adopted with the DS-modulator–DS *** phase space of the e beam is appropriately coupled in the first DS,and the electrons within one seed wavelength can merge to the same phase with a matched second ***-bunching of the e beam can thus be enhanced by a large margin with much higher-harmonic *** e beams from laser wakefield accelerators(LWFAs)as an example,start-to-end simulations are performed to show the effectiveness and robustness of the proposed schemes with several *** beam current can be optimized to several tens to hundreds of kiloamperes,and the radiation power reaches hundreds of megawatts in the extreme ultraviolet regime within a 3.5 m-long *** proposed schemes offer new opportunities for future compact free-electron lasers driven by LWFAs and provides prospects for truly compact and widely applicable systems.

关键词： modulator harmonic phase