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一种临近空间高超声速目标检测前跟踪算法

宇航学报 2017年第4期38卷 420-427页

作者：李林王国宏于洪波谭顺成海军航空工程学院信息融合研究所烟台264001

针对传统算法无法对临近空间高超声速目标进行有效检测的问题,提出了一种基于Hough变换和多条件约束的检测前跟踪算法。首先采用时间-径向距离量测(TBD)数据进行Hough变换,将参数空间变量θ作为积累约束条件来避免无效积累,得到目标可... 详细信息

针对传统算法无法对临近空间高超声速目标进行有效检测的问题,提出了一种基于Hough变换和多条件约束的检测前跟踪算法。首先采用时间-径向距离量测(TBD)数据进行Hough变换,将参数空间变量θ作为积累约束条件来避免无效积累,得到目标可能航迹;之后对所有可能航迹进行速度约束和航向约束,进一步剔除虚假航迹和航迹内杂波点;最后对同一目标航迹进行合并,得到最终确认航迹。通过仿真对算法有效性进行了验证,并分析了不同信噪比和杂波密度条件下的算法性能,仿真结果表明,算法能够在杂波环境下对临近空间高超声速目标进行有效检测。

关键词： Hough变换多条件约束临近空间高超声速目标检测前跟踪(TBD)

Toward understanding the microstructure characteristics,phase selection and magnetic properties of laser additive manufactured Nd-Fe-B permanent magnets

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International Journal of Extreme Manufacturing 2024年第1期6卷 277-294页

作者： bo Yao Nan Kang Xiangyu Li Dou Li Mohamed EL Mansori Jing Chen Haiou Yang Hua tan Xin Lin State Key Laboratory of Solidiffcation Processing Northwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Arts et Metiers Institute of Technology MSMPHESAM UniversitéF-51006 Chˆalons-en-ChampagneFrance Key Laboratory of Metal High Performance Additive Manufacturing and Innovative Design MIIT ChinaNorthwestern Polytechnical UniversityXi’anShaanxi 710072People’s Republic of China Texas A&M Engineering Experiment Station Institute for Manufacturing SystemsCollege StationTX 77843United States of America

Nd-Fe-B permanent magnets play a crucial role in energy conversion and electronic *** essential magnetic properties of Nd-Fe-B magnets,particularly coercivity and remanent magnetization,are significantly infuenced by the phase characteristics and *** this work,Nd-Fe-B magnets were manufactured using vacuum induction melting(VIM),laser directed energy deposition(LDED)and laser powder bed fusion(LPBF)*** evolution and phase selection of Nd-Fe-B magnets were then clarified in *** results indicated that the solidification velocity(V)and cooling rate(R)are key factors in the phase *** terms of the VIM-casting Nd-Fe-B magnet,a large volume fraction of theα-Fe soft magnetic phase(39.7 vol.%)and Nd2Fe17Bxmetastable phase(34.7 vol.%)areformed due to the low R(2.3×10-1?C s-1),whereas only a minor fraction of the Nd2Fe14B hard magnetic phase(5.15 vol.%)is *** the LDED-processed Nd-Fe-B deposit,although the Nd2Fe14B hard magnetic phase also had a low value(3.4 vol.%)as the values of V(both the VIM-casting and LDED-processed Nd-Fe-B deposits exhibited poor magnetic *** contrast,employing the high values of V(>10-2m s-1)and R(1.45×106?C s-1)in the LPBF process resulted in the substantial formation of the Nd2Fe14B hard magnetic phase(55.8 vol.%)directly from the liquid,while theα-Fe soft magnetic phase and Nd2Fe17Bxmetastable phase precipitation are suppressed in the LPBF-processed Nd-Fe-B ***,crystallographic texture analysis reveals that the LPBF-processedNd-Fe-B magnets exhibit isotropic magnetic ***,the LPBF-processed Nd-Fe-B deposit,exhibiting a coercivity of 656 k A m-1,remanence of 0.79 T and maximum energy product of 71.5 k J m-3,achieved an acceptable magnetic perfor

关键词： laser additive manufacturing(LAM) Nd-Fe-B permanent magnets numerical simulation microstructure magnetic properties

In-situ coating and surface partial protonation co-promoting performance of single-crystal nickel-rich cathode in all-solid-state batteries

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Journal of Energy Chemistry 2024年第2期89卷 137-143,I0005页

作者： Maoyi Yi Jie Li Mengran Wang Xinming Fan bo hong Zhian Zhang Aonan Wang Yanqing Lai School of Metallurgy and Environment Central South UniversityChangsha 410083HunanChina Engineering Research Centre of Advanced Battery Materials The Ministry of EducationChangsha 410083HunanChina Hunan Province Key Laboratory of Nonferrous Value-Added Metallurgy Central South UniversityChangsha 410083HunanChina

The poor electrochemical performance of all-solid-state batteries(ASSBs),which is assemblied by Ni-rich cathode and poly(ethylene oxide)(PEO)-based electrolytes,can be attributed to unstable cathodic interface and poor crystal structure stability of Ni-rich *** coating strategies are previously employed to enhance the stability of the cathodic interface and crystal structure for Ni-rich ***,these methods can hardly achieve simplicity and high efficiency *** this work,polyacrylic acid(PAA)replaced traditional PVDF as a binder for cathode,which can achieve a uniform PAA-Li(LixPAA(0

关键词： Single-crystal LiNi_(0.83)Co_(0.12)Mn_(0.05)O_(2) In-situ coating PAA-Li Partial protonation

Effect of aflibercept combined with triamcinolone acetonide on aqueous humor growth factor and inflammatory mediators in diabetic macular edema

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International Journal of Ophthalmology(English edition) 2024年第2期17卷 297-303页

作者： De-Shuang Li hong-Xia Liao Jing-Lin Zhang bo Qin Shenzhen Aier Eye Hospital Aier Eye HospitalJinan UniversityShenzhen 518031Guangdong ProvinceChina Guangzhou Aier Eye Hospital Jinan UniversityGuangzhou 510040Guangdong ProvinceChina

AIM:To investigate the efficacy of aflibercept combined with sub-tenon injection of triamcinolone acetonide(TA)in treating diabetic macular edema(DME)and to examine changes in growth factors and inflammatory mediator levels in aqueous humor after ***:Totally 67 DME patients(67 eyes)and 30 cataract patients(32 eyes)were enrolled as the DME group and the control group,*** DME group was divided into the aflibercept group(34 cases)and the aflibercept combined with TA group(combined group,33 cases).The aqueous humor of both groups was collected during the study *** aqueous levels of vascular endothelial growth factor(VEGF),monocyte chemoattractant protein-1(MCP-1),interleukin-6(IL-6),interleukin-8(IL-8),and interleukin-1β(IL-1β)were detected using a microsphere suspension array technology(Luminex 200TM).Aqueous cytokines,best-corrected visual acuity(BCVA),central macular thickness(CMT),and complications before and after treatment were compared between the aflibercept group and combined ***:The concentrations of VEGF,MCP-1,IL-6,and IL-8 in the aqueous humor were significantly higher in the DME group than those of the control group(all P0.05).CONCLUSION:The cytokines VEGF,MCP-1,IL-6,and IL-8 in the aqueous humor of DME patients are significantly *** and aflibercept combined with TA have good efficacy in DME patients,can effectively reduce CMT,improve the patient’s vision,and have high *** combined with TA can quickly downregulate the aqueous humor cytokines and help to relieve macular edema ***,the long-term eff

关键词： diabetic macular edema aqueous humor cytokines aflibercept triamcinolone acetonide

An innovative classification system for ranking the biological effects of marine aromatic hydrocarbons based on fish embryotoxicity

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Acta Oceanologica Sinica 2024年第6期43卷 153-162页

作者： Ronghui Zheng Chao Fang Fukun hong Min Zhang Fulong Gao Yusheng Zhang Jun bo Key Laboratory of Marine Ecological Conservation and Restoration Third Institute of OceanographyMinistry of Natural ResourcesXiamen 361005China Observation and Research Station of Coastal Wetland Ecosystem in Beibu Gulf Ministry of Natural ResourcesBeihai 536015China

Petroleum hydrocarbon pollution is a global concern,particularly in coastal *** aromatic hydrocarbons(PAHs) are regarded as the most toxic components of petroleum *** this study,the biomonitoring and ranking effects of petroleum hydrocarbons and PAHs on the marine fish model Oryzias melastigma embryos were determined in the Jiulong River Estuary(JRE) and its adjacent waters in *** results showed that the levels of petroleum hydrocarbons from almost all sites met the primary standard for marine seawater quality,and the concentrations of the 16 priority PAHs in the surface seawater were lower compared with those in other coastal areas worldwide.A new fish expert system based on the embryotoxicity of ***(OME-FES) was developed and applied in the field to evaluate the biological effects of petroleum hydrocarbons and *** selected physiological index and molecular indicators in OME-FES were appropriate biomarkers for indicating the harmful effects of petroleum hydrocarbons and *** outcome of OME-FES revealed that the biological effect levels of the sampling sites ranged from level Ⅰ(no stress) to level Ⅲ(medium stress),which is further corroborated by the findings of nested analysis of variance(ANOVA) *** results suggest that the OME-FES is an effective tool for evaluating and ranking the biological effects of marine petroleum hydrocarbons and *** method may also be applied to evaluate other marine pollutants based on its framework.

关键词： petroleum hydrocarbons polycyclic aromatic hydrocarbons fish expert system integrated biomarker response nested one-way analysis of variance

Low Selenium and Low Protein Exacerbate Myocardial Damage in Keshan Disease by Affecting the PINK1/Parkin-mediated Mitochondrial Autophagy Pathway

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Current Medical Science 2024年第1期44卷 93-101页

作者： Li-wei ZHANG hong-qi FENG Song-bo FU Dian-jun SUN Center for Endemic Disease Control Chinese Center for Disease Control and PreventionHarbin Medical UniversityNHC Key Laboratory of Etiology and Epidemiology(Harbin Medical University)Key Lab of Etiology and EpidemiologyEducation Bureau of Heilongjiang ProvinceHarbin 150086China

Objective Keshan disease(KD)is a myocardial mitochondrial disease closely related to insufficient selenium(Se)and protein *** induced putative kinase 1(PINK1)/Parkin mediated mitochondrial autophagy regulates various physiological and pathological processes in the *** study aimed to elucidate the relationship between PINK1/Parkin-regulated mitochondrial autophagy and KD-related myocardial *** A low Se and low protein animal model was *** hundred Wistar rats were randomly divided into 5 groups(control group,low Se group,low protein group,low Se+low protein group,and corn from KD area group).The JC-1 method was used to detect the mitochondrial membrane potential(MMP).ELISA was used to detect serum creatine kinase MB(CK-MB),cardiac troponin I(cTnI),and mitochondrial-glutamicoxalacetic transaminase(M-GOT)***-PCR and Western blot analysis were used to detect the expression of PINK1,Parkin,sequestome 1(P62),and microtubule-associated proteins1A/1B light chain 3B(MAP1LC3B).Results The MMP was significantly decreased and the activity of CK-MB,cTnI,and M-GOT significantly increased in each experimental group(low Se group,low protein group,low Se+low protein group and corn from KD area group)compared with the control group(P<0.05 for all).The mRNA and protein expression levels of PINK1,Parkin and MAP1LC3B were profoundly increased,and those of P62 markedly decreased in the experimental groups compared with the control group(P<0.05 for all).Conclusion Low Se and low protein levels exacerbate myocardial damage in KD by affecting the PINK1/Parkin-mediated mitochondrial autophagy pathway.

关键词： Keshan disease low selenium and low protein myocardial mitochondrial injury PTEN induced putative kinase 1(PINK1)/Parkin mitochondrial autophagy

Biomimetic chitin hydrogel via chemical transformation

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Nano Research 2024年第2期17卷 771-777页

作者： Rui-Rui Liu Qian-Qian Shi Yu-Feng Meng Yong Zhou Li-bo Mao Shu-hong Yu Division of Nanomaterials&Chemistry Hefei National Research Center for Physical Sciences at the MicroscaleDepartment of ChemistryInstitute of Biomimetic Materials&ChemistryAnhui Engineering Laboratory of Biomimetic MaterialsUniversity of Science and Technology of ChinaHefei 230026China College&Hospital of Stomatology Key Laboratory of Oral Diseases Research of Anhui ProvinceAnhui Medical UniversityHefei 230032China Department of Dental Implantology College&Hospital of StomatologyAnhui Medical UniversityHefei 230032China

Chitin hydrogel has been recognized as a promising material for various biomedical applications because of its biocompatibility and ***,the fabrication of strong chitin hydrogel remains a big challenge because of the insolubility of chitin in many solvents and the reduced chain length of chitin regenerated from *** herein introduce the fabrication of chitin hydrogel with biomimetic structure through the chemical transformation of chitosan,which is a water-soluble deacetylated derivative of *** reacetylation of the amino group in chitosan endows the obtained chitin hydrogel with outstanding resistance to swelling,degradation,extreme temperature and pH conditions,and organic *** chitin hydrogel has excellent mechanical properties while retaining a high water content(more than 95 wt.%).It also shows excellent antifouling performance that it resists the adhesion of proteins,bacteria,blood,and ***,as the initial chitosan solution can be feasibly frozen and templated by ice crystals,the chitin hydrogel structure can be either nacre-like or wood-like depending on the freezing method of the precursory chitosan *** to these anisotropic structures,such chitin hydrogel can exhibit anisotropic mechanics and mass transfer *** current work provides a rational strategy to fabricate chitin hydrogels and paves the way for its practical applications as a superior biomedical material.

关键词： chitin hydrogel biomimetic structure chemical stability mechanical strength antifouling

Quantitative method to predict the energetics of helium-nanocavities interactions in metal systems based on electrophobic interaction

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Journal of Materiomics 2024年第3期10卷 725-737页

作者： Fengping Luo bowen Zhang Zhiying Gao Jia Huang hong-bo Zhou Guang-hong Lu Fei Gao Yugang Wang Chenxu Wang State Key Laboratory of Nuclear Physics and Technology Center for Applied Physics and TechnologyPeking UniversityBeijing100871China Department of Physics Beihang UniversityBeijing100191China Department of Nuclear Engineering and Radiological Science University of MichiganAnn ArborMI48109USA

Energetics of helium-nanocavities interactions are crucial for unveiling underlying mechanisms of nanocavity evolution in nuclear ***,it becomes intractable and even not feasible to obtain these energetics via atomic simulations with increasing nanocavity size and increasing helium content in ***,a universal scaling law of helium-induced interaction energies in nanocavities in metal systems is proposed based on electrophobic interaction of *** on this scaling law and ab-initio calculations,a predictive method for binding energies of helium and displacement defects to nanocavities of arbitrary sizes and with different helium/vacancy ratios is established for BCC iron as a representative and validated by atomic *** predictive method reveals that the critical helium/vacancy ratio for helium-enhanced vacancy binding to nanocavities in-creases with increasing nanocavity size,and the helium/vacancy ratio giving the highest stability of nanocavities is about *** Ostwald ripening of nanocavities is delayed by helium to higher temper-atures due to reduced vacancy de-trapping rates from *** proposed scaling law can be generalized to many metal systems studied in the nuclear materials *** readily coupled into mesoscale models of irradiation damages,this predictive method facilitates clarifying helium role in cavity swelling of metallic nuclear materials.

关键词： Nanocavities Helium Electrophobic interaction Predictive method

Multiple Matching Attenuation Based on Curvelet Domain Extended Filtering

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Journal of Ocean University of China 2024年第4期23卷 924-932页

作者： HUA Qingfeng CHEN Zhang HE Huili tan Jun CHEN Haifeng LI Guanbao SONG Peng ZHAO bo JIANG Xiuping Key Laboratory of Marine Geology and Metallogeny First Institute of OceanographyMinistry of Natural ResourcesQingdao 266061China Laboratory for Marine Mineral Resources Qingdao Marine Science and Technology CenterQingdao 266237China College of Marine Geoscience Ocean University of ChinaQingdao 266100China BGP Inc. China National Petroleum CorporationZhuozhou 072750China Key Laboratory of Submarine Geosciences and Prospecting Techniques Ministry of EducationQingdao 266100China

The paper develops a multiple matching attenuation method based on extended filtering in the curvelet domain,which combines the traditional Wiener filtering method with the matching attenuation method in curvelet ***,the method uses the predicted multiple data to generate the Hilbert transform records,time derivative records and time derivative records of Hilbert ***,the above records are transformed into the curvelet domain and multiple matching attenuation based on least squares extended filtering is ***,the attenuation results are transformed back into the time-space *** on the model data and field data show that the method proposed in the paper effectively suppress the multiples while preserving the primaries ***,it has higher accuracy in eliminating multiple reflections,which is more suitable for the multiple attenuation tasks in the areas with complex structures compared to the time-space domain extended filtering method and the conventional curvelet transform method.

关键词： multiple matching attenuation curvelet domain extended filtering