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Design and Analysis of Biomimetic Nose Cone for Morphing of Aerospace Vehicle

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Journal of Bionic Engineering 2017年第2期14卷 317-326页

作者： Jieliang Zhao Shaoze Yan Liren Deng He Huang yueming liu Division of Intelligent and Biomechanical Systems State Key Laboratory of Tribology Department of Mechanical Engineering Tsinghua University Beijing 100084 China

Morphing capability is absolutely vital for aerospace vehicle to gain predominant functions of aerodynamics, mobility and flight control while piercing and re-entering the atmosphere. However, the challenge for existing aerospace vehicle remains to change its structure of nose cone agilely. This paper carries out a lot of observational experiments on honeybee＇s abdomen which enhances the flight characteristics of honeybee by adjusting its biomorphic shape. A morphing structure is adopted from honeybee＇s abdomen to improve both the axial scalability and bending properties of aerospace vehicle, which can lead to the super-maneuver flight performance. Combined with the methods of optimum design and topology, a new bionic morphing structure is proposed and applied to the design of morphing nose cone of aerospace vehicle. Furthermore, simulations are conducted to optimize the structural parameters of morphing nose cone. This concept design of biomimetic nose cone will provide an efficient way for aerospace vehicle to reduce the aerodynamic drag.

关键词： bio-inspired design honeybee morphing nose cone aerospace vehicle flight characteristic

Effect of Sr^2+ and Dy^3+ co-doping on coloration and temperature stabilization of a γ-Ce2S3 red pigment

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Journal of Rare Earths 2020年第2期38卷 213-218页

作者： yueming Li Qi liu Fusheng Song Zhumei Wang Zongyang Shen Yan Hong National Light Industry Key Laboratory of Functional Ceramic Materials Energy Storage and Conversion Ceramic Materials Engineering Laboratory of Jiangxi ProvinceSchool of Materials Science and EngineeringJingdezhen Ceramic InstituteJingdezhen 333403China

In this paper,a Sr^2+and Dy^3+co-doped γ-Ce2S3 red pigment was synthesized via a combination of coprecipitation and sulfurization *** oxide was prepared by presintering the coprecipitates,(Ce,Sr,Dy)CO3,followed by high-temperature sulfurization under a CS2 *** effects of the sulfurization temperature,time,and doped proportion on the phase composition,color performance and temperature stability of γ-Ce2S3 were systematically *** results show that a stable γ-Ce2S3 red pigment can be obtained through Sr^2+and Dy^3+co-doping at 730℃ for 200 *** diffraction peaks of all the samples shift to higher 2θ values with increasing doping proportion,indicating that part of the Dy^3+species enter the lattice and form a solid *** band gap of the samples remains practically constant at 2.01-2.04 eV,which causes their red *** best red-color quality(L*=37.13,a*=34.77,b*=29.44) is achieved when the pigment has a Dy^3+/Ce^3+molar ratio of 0.15,and the material maintains its excellent red color(L*=31.49 a*=30.94 b*=25.33) after being heated at 410℃ for 30 min.

关键词： γ-Ce2S3 Red pigment Co-precipitation Sr^2+,Dy^3+ co-doped Rare earths

Object-based classification of cloudy coastal areas using medium-resolution optical and SAR images for vulnerability assessment of marine disaster

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Journal of Oceanology and Limnology 2019年第6期37卷 1955-1970页

作者： YANG Fengshuo YANG Xiaomei WANG Zhihua LU Chen LI Zhi liu yueming State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China University of Chinese Academy of Sciences Beijing 100049China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China Jiangsu Centre for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Efficient and accurate access to coastal land cover information is of great significance for marine disaster prevention and *** the popular and common sensors of land resource satellites provide free and valuable images to map the land cover,coastal areas often encounter significant cloud cover,especially in tropical areas,which makes the classification in those areas *** solve this problem,we proposed a framework of combining medium-resolution optical images and synthetic aperture radar(SAR)data with the recently popular object-based image analysis(OBIA)method and used the Landsat Operational Land Imager(OLI)and Phased Array type L-band Synthetic Aperture Radar(PALSAR)images acquired in Singapore in 2017 as a case *** designed experiments to confirm two critical factors of this framework:one is the segmentation scale that determines the average object size,and the other is the classification *** assessments of the land cover indicated that the optimal segmentation scale was between 40 and 80,and the features of the combination of OLI and SAR resulted in higher accuracy than any individual features,especially in areas with cloud *** on the land cover generated by this framework,we assessed the vulnerability of the marine disasters of Singapore in 2008 and 2017 and found that the high-vulnerability areas mainly located in the southeast and increased by 118.97 km2 over the past *** clarify the disaster response plan for different geographical environments,we classified risk based on altitude and distance from *** newly increased high-vulnerability regions within 4 km offshore and below 30 m above sea level are at high risk;these regions may need to focus on strengthening disaster prevention *** study serves as a typical example of using remote sensing techniques for the vulnerability assessment of marine disasters,especially those in cloudy coastal areas.

关键词： coastal area marine disaster vulnerability assessment remote sensing land use/cover object-based image analysis(OBIA)

Aquaculture area extraction and vulnerability assessment in Sanduao based on richer convolutional features network model

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Journal of Oceanology and Limnology 2019年第6期37卷 1941-1954页

作者： liu yueming YANG Xiaomei WANG Zhihua LU Chen LI Zhi YANG Fengshuo State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijing 100101China State Key Laboratory of Desert and Oasis Ecology Xinjiang Institute of Ecology and GeographyChinese Academy of SciencesUrumqi 830011China University of Chinese Academy of Sciences Beijing 100049China Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application Nanjing 210023China

Sanduao is an important sea-breeding bay in Fujian,South China and holds a high economic status in *** and accurately obtaining information including the distribution area,quantity,and aquaculture area is important for breeding area planning,production value estimation,ecological survey,and storm surge ***,as the aquaculture area expands,the seawater background becomes increasingly complex and spectral characteristics differ dramatically,making it difficult to determine the aquaculture *** this study,we used a high-resolution remote-sensing satellite GF-2 image to introduce a deep-learning Richer Convolutional Features(RCF)network model to extract the aquaculture *** we used the density of aquaculture as an assessment index to assess the vulnerability of aquaculture areas in *** results demonstrate that this method does not require land and water separation of the area in advance,and good extraction can be achieved in the areas with more sediment and waves,with an extraction accuracy>93%,which is suitable for large-scale aquaculture area *** assessment results indicate that the density of aquaculture in the eastern part of Sanduao is considerably high,reaching a higher vulnerability level than other parts.

关键词： aquaculture area vulnerability assessment Richer Convolutional Features(RCF)network model deep learning high-resolution remote sensing

Ti_(3)C_(2)T_(x)MXene wrapped,carbon-coated porous Si sheets for improved lithium storage performance

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Chinese Chemical Letters 2024年第2期35卷 617-621页

作者： Hui Cheng yueming liu Zhongling Cheng Xianying Wang Na Huang Haijiao Zhang Institute of Nanochemistry and Nanobiology School of Environmental and Chemical EngineeringShanghai UniversityShanghai 200444China Shanghai Key Laboratory of Green Chemistry and Chemical Processes School of Chemistry and Molecular EngineeringEast China Normal UniversityShanghai 200062China Energy Materials Research Center AG Hydrogen Materials & Devices CAS Key Laboratory of Materials for Energy ConversionShanghai Institute of CeramicsChinese Academy of Sciences (SICCAS)Shanghai 200050China

Si-based materials have shown great potential as lithium-ion batteries(LIBs)anodes due to their natural reserves and high theoretical ***,the large volume changes during cycles and poor conductivity of Si lead to rapid capacity decay and poor cycling stability,ultimately limiting their commercial ***,we have skillfully utilized the microporous MCM-22 zeolite as the unique silicon source to produce porous Si(pSi)sheets by a simple magnesiothermic reduction,followed by a carbon coating and further Ti_(3)C_(2)T_(x)MXene assembly,obtaining the ternary pSi@NC@TNSs *** the design,porous Si sheets provide more active sites and shorten Li-ion transport paths for electrochemical *** N-doped carbon(NC)layer serves as a bonding layer to couple pSi and Ti_(3)C_(2)T_(x).The conductive network formed by 2D Ti_(3)C_(2)T_(x)and medium NC layer effectively enhances the overall charge transport of the electrode material,and helps to stabilize the electrode ***,the as-made pSi@NC@TNSs anode delivers an improved lithium storage performance,exhibiting a high reversible capacity of 925 mAh/g at 0.5 A/g after 100 *** present strategy provides an effective way towards high-performance Si-based anodes for LIBs.

关键词： Si anodes Ti_(3)C_(2)Ti_(x)MXene Porous structure Interfacial assembly Lithium-ion batteries

Mapping China’s offshore mariculture based on dense time-series optical and radar data

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International Journal of Digital Earth 2022年第1期15卷 1326-1349页

作者： Xiaoliang liu Zhihua Wang Xiaomei Yang yueming liu Bin liu Junyao Zhang Ku Gao Dan Meng Yaxin Ding State Key Laboratory of Resources and Environmental Information System Institute of Geographic Sciences and Natural Resources ResearchChinese Academy of SciencesBeijingPeople’s Republic of China University of Chinese Academy of Sciences BeijingPeople’s Republic of China

Due to the weak information about cultural targets in the complex marine environment,an omission problem exists in large-scale mariculture extraction using single-view and single-source *** overcome this problem,we developed a mariculture extraction method that combines dense time-series Sentinel-2 and Sentinel-1 data.A high-precision Chinese mariculture distribution map for 2020 was produced with an overall accuracy of 94.00%and a kappa coefficient of *** results show that(1)the total area of mariculture was 1173249.22 ha on the national scale,which was significantly larger than the previous studies(459595.70 and 205920.28 ha,respectively),with Shandong Province(39.09%)having the largest proportion;(2)China’s mariculture presented a spatial distribution characteristic of‘Denser North and Sparser South’,and mariculture was centralized in the coastal zones of the northern provinces(60.76%)rather than the southern provinces;(3)the official production statistics and remote sensing-derived mariculture area revealed a highly corresponding trend at the provincial level,with an R2 reaching 0.78,which is much higher than the 0.07 and 0.41 values of the comparison *** results directly provide data reference for mariculture production estimation and site selection or ideas for mariculture extraction in other regions and globally.

关键词： Aquaculture mariculture multi-source remote sensing time-series China’s coastal zone

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AFRICA

Contemporary International Relations 1997年第1期7卷 10-12页

作者： liu yueming

1997 seems to be another promising year for Africa. Conflicts among nationswill be further eased and domestic situation of many countries get more *** is because in the majority of African countries, "multi-party democraticsystems" have been set up preliminarily. This is of course conducive to the stabilityof the countries concerned. Last year, a dozen of African countries held their mul-

关键词： AFRICA down

Novel circular RNA expression profile of uveal melanoma revealed by microarray

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Chinese Journal of Cancer Research 2018年第6期30卷 656-668页

作者： Xuan Yang Yang Li yueming liu Xiaolin Xu Yingzhi Wang Yanni Yan Wenjia Zhou Jingyan Yang Wenbin Wei Beijing Tongren Eye Center Beijing Key Laboratory of Intraocular Tumor Diagnosis and TreatmentBeijing Ophthalmology & Visual Sciences Key LabBeijing Tongren HospitalCapital Medical University Beijing Institute of Ophthalmology Beijing Key Laboratory of Intraocular Tumor Diagnosis and TreatmentBeijing Tongren Eye CenterBeijing Tongren HospitalCapital Medical UniversityBeijing Ophthalmology & Visual Sciences Key Laboratory

Objective: The present study aimed to investigate circular RNA(circRNA) expression in uveal melanoma(UM).Methods: First,we used microarray to compare the expression profiles of circRNA in five UM samples and five normal uvea ***,bioinformatics analyses,including gene ontology(GO) analysis and pathway analysis,were applied to study these differentially expressed circRNAs to predict pathogenic pathways that may be *** real-time polymerase chain reaction(qRT-PCR) in 20 UM samples and 20 normal uvea samples was used to confirm the circRNA expression profiles obtained from the microarray ***,we analyzed the interaction between validated circRNAs and their potential cancer-associated miRNA ***: In total,50,579 circRNAs [fold change(FC) ≥2.0; P<0.05],including 20,654 up-regulated and 29,925 down-regulated circRNAs,were identified as differentially expressed between UM tissues and normal uvea *** used qRT-PCR to verify seven dysregulated circRNAs indicated by the microarray data,including hsacirc0119873,hsacirc0128533,hsacirc0047924,hsacirc0103232,hsa-circRNA10628-6,hsacirc0032148 and hsacirc0133460,which may be promising candidates to study future molecular ***: This study explored,for the first time,the abnormal expression of circRNAs in UM and described the expression profile of circRNAs,providing a new potential target for the mechanism of UM and future treatment of UM.

关键词： Uveal melanoma circular RNA microarray noncoding RNA

Feeder assignment optimization algorithm for multi-head mounter

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控制理论与应用（英文版） 2006年第3期4卷 223-228页

作者： Peng YUAN yueming HU Haiming liu Hongxia GAO College of Automation Science and Engineering South China University of Technology Guangzhou Guangdong 510640 China

This paper analyzes optimization algorithms of assembly time for a multi-head mounter. The algorithm in this paper is composed of four steps. First, it assigns the components to feeders based on the ＂one-to-many mapping＂. Secondly, it assigns nozzles to heads by making full use of the ＂on-the-fly nozzle change＂ heads. Thirdly, it Qrganizes the feeder groups so that the heads can pick and place components group by group. Finally, it assigns feeder groups to slots. The result demonstrates that the algorithm has good performance in practice.

关键词： Mounter Feeder assignment Optimization