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A Correlation-Based Stochastic Model for Massive MIMO Channel

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China Communications 2024年第1期21卷 175-187页

作者： Yang Liu gang Li Chengxiang Wang National Mobile Communications Research Laboratory School of Information Science and EngineeringSoutheast UniversityNanjing 211189China School of Internet of Things Engineering Jiangnan UniversityWuxi 214122China Pervasive Communication Research Center Purple Mountain LaboratoriesNanjing 211111China

In this paper,the channel impulse response matrix(CIRM)can be expressed as a sum of couplings between the steering vectors at the base station(BS)and the eigenbases at the mobile station(MS).Nakagami distribution was used to describe the fading of the coupling between the steering vectors and the *** measurements were carried out to evaluate the performance of this proposed ***,the physical implications of this model were illustrated and the capacities are *** addition,the azimuthal power spectrum(APS)of several models was ***,the channel hardening effect was simulated and *** showed that the proposed model provides a better fit to the measured results than the other CBSM,i.e.,Weichselberger ***,the proposed model can provide better tradeoff between accuracy and complexity in channel *** CIRM model can be used for massive MIMO design in the future communication system design.

关键词： CBSM channel capacity channel hardening channel modeling massive MIMO

Research on human gait sensing based on triboelectric nanogenerator

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Nanotechnology and Precision Engineering 2024年第2期7卷 32-40页

作者： gang Yang Lifang Wang Jiayun Tian School of Communication and Information Engineering Xi’an University of Posts and TelecommunicationsXi’an 710121China

To address the problem of frequent battery replacement for wearable sensors applied to fall detection among the elderly,a portable and lowcost triboelectric nanogenerator(TENG)-based self-powered sensor for human gait monitoring is *** main fabrication materials of the TENG are polytetrafluoroethylene(PTFE)film,aluminum(Al)foil,and polyimide(PI)film,where PTFE and Al are the friction layer materials and the PI film is used to improve the output *** the ability of TENGs to monitor changes in environmental conditions,a self-powered sensor based on the TENG is placed in an insole to collect gait *** a TENG does not require a power source to convert physical and mechanical signals into electrical signals,the electrical signals can be used as sensing signals to be analyzed by a computer to recognize daily human activities and fall *** results show that the accuracy of the TENG-based sensor for recognizing human gait is 97.2%,demonstrating superior sensing performance and providing valuable insights for future monitoring of fall events in the elderly population.

关键词： Triboelectric nanogenerator Sensor Gait monitoring

Recent Advances in Nickel Catalyzed Carbonylative Reactions via the Insertion of Carbon Monoxide

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Chinese Journal of Chemistry 2024年第2期42卷 177-189页

作者： Xinzhou Chen gang Chen Zhong Lian Department of Dermatology State Key Laboratory of Biotherapy and Cancer CenterWest China HospitalSichuan UniversityChengduSichuan 610041China

Carbonyl compounds have attracted considerable attention due to their extensive applications in drug ***,they are important synthetic intermediates for the construction of carbon-carbon and carbon-heteroatom ***-metal-catalyzed carbonylation via the insertion of co is one of the most efficient and straightforward strategies to access carbonyl ***,most of the transition-metal-catalyzed carbonylative reactions require expensive and toxic noble-metal ***,there is a growing demand for the exploration of nickel-catalyzed carbonylative reactions via the insertion of CO due to the earth abundance and low cost of *** with the well-established palladium-catalyzed carbonylative reactions,nickel-catalyzed analogous transformations have been relatively *** is primarily because CO strongly binds to nickel,often resulting in catalyst *** recent years,some research groups have focused on using CO surrogates or NN_(2) pincer nickel catalyst to circumvent the formation of Ni(CO)_(4).Nickel-catalyzed carbonylation has been applied in the construction of carbonyl-containing compounds,such as ketones,carboxylic acids,thioesters,acyl chloride and carboxamides.

关键词： Carbonylation Nickel catalysis Carbon monoxide C1 chemistry Carbonyl-containing compounds

Synthesis of Organofluorine Compounds with Acylsilanes

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Chinese Journal of Chemistry 2024年第8期42卷 887-902页

作者： Youyuan Guo gang Zhou Xiao Shen The Institute for Advanced Studies Engineering Research Center of Organosilicon Compounds&MaterialsMinistry of EducationWuhan University299 Bayi RoadWuhanHubei430072 China

Comprehensive Summary,Organofluorine compounds are central in synthetic chemistry,medicinal chemistry and material *** this review,we summarize the investigations on the synthesis of organofluorine compounds with *** the non-fluorinated acylsilanes,the in situ generation of difluoroenoxysilanes from the reactions of the acylsilanes with trifluoromethylation reagents is the major pathway,leading to the facile preparation of variousα,α-*** the fluoroalkylacylsilanes,apart from the in situ generation of difluoroenoxysilanes through anion Brook rearrangement,radical Brook rearrangement of the photoexcited acylsilanes and the selective control of reactivities of the biradicals pave the way for the synthesis of a variety of organofluorine *** general,most of these reactions gave racemic products,and the asymmetric synthesis of organofluorine compounds with acylsilanes is still rare,which would be a future.

关键词： Acylsilanes Organofluorine compounds Brook rearrangement Radical rearrangement β-Fluoride elimination Asymmetric catalysis Photocatalysis Defluoroalkylation

Comparative analysis of the microbiome of sympatric wintering Bean Geese,Domestic Ducks,humans,and soil at Shengjin Lake of China reveals potential public risk to human health

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Avian Research 2024年第2期15卷 279-286页

作者： gang Liu Na Xu Chongyang Yu College of Life Sciences Anhui Medical UniversityHefei 230032China

The gut microbiota of migratory waterbirds is affected by various complex factors,including cross-species transmission,which increases the risk of pathogen spreading among sympatric animals and poses a potential public health risk to *** this study,we investigated the microbial communities of wintering Bean Geese(Anser fabalis),Domestic Ducks(*** domesticus),humans,and soil using high-throughput sequencing of the 16S rRNA gene region in Shengjin Lake,*** total,6,046,677 clean reads were obtained,representing 41,119 operational taxonomic units(OTUs)across the four *** dominant microbial phyla were the Proteobacteria,Firmicutes,Bacteroidota,and *** Sorensen similarity index and alpha and beta diversity results showed that the gut microbial communities of Bean Geese and Domestic Ducks were more similar to those of the other *** analysis revealed that Faecalibacterium prausnitzii,Pseudomonas fragi,and Bradyrhizobium elkanii were hubs of the three major *** common microbiomes were iden-tified in Bean Geese,Domestic Ducks,humans,and soil in Shengjin Lake.A total of 96 potential pathogens were identified among the four groups,with 20 specific potentially pathogenic microbiomes found in the gut of Bean *** of these pathogens are responsible for significant financial losses in the poultry industry and pose risks to human *** pneumoniae,Morganella morganii,Escherichia coli,and Ralstonia insidiosa are potential core pathogens found in the four groups at Shengjin Lake that can cause diseases in humans and an-imals and facilitate cross-species transmission through various ***,humans are at risk of con-tracting these pathogens from migratory birds because of their frequent contact with domestic ***,further studies are required to explore the potential pathogenic species and transmission pathways among sympatric wintering Bean Geese,Domestic Ducks,humans,and soil.

关键词： Microbiome Migratory waterbird Pathogens Poultry Sympatric species

Phylotranscriptomic discordance is best explained by incomplete lineage sorting within Allium subgenus Cyathophora and thus hemiplasy accounts for interspecific trait transition

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Plant Diversity 2024年第1期46卷 28-38页

作者： Zengzhu Zhang gang Liu Minjie Li State Key Laboratory of Herbage Improvement and Grassland Agro-Ecosystems College of EcologyLanzhou UniversityLanzhou 730000GansuPR China

The transition of traits between genetically related lineages is a fascinating topic that provides clues to understanding the drivers of speciation and *** can be learned about this process from phylogeny-based trait ***,such inference is often plagued by genome-wide gene-tree discordance(GTD),mostly due to incomplete lineage sorting(ILS)and/or introgressive hybridization,especially when the genes underlying the traits appear ***,by collecting transcriptomes,whole chloroplast genomes(cpDNA),and population genetic datasets,we used the coalescent model to turn GTD into a source of information for ILS and employed hemiplasy to explain specific cases of apparent“phylogenetic discordance”between different morphological traits and probable species phylogeny in the Allium *** concatenation and coalescence methods consistently showed the same phylogenetic topology for species tree inference based on single-copy genes(SCGs),as supported by the KS ***,GTD was high across the genomes of ***:~27%e38.9%of the SCG trees were in conflict with the species *** and nuclear incongruence was also *** coalescent simulations indicated that such GTD was mainly a product of *** hemiplasy risk factor calculations supported that random fixation of ancient polymorphisms in different populations during successive speciation events along the *** phylogeny may have caused the character transition,as well as the anomalous cpDNA *** study exemplifies how phylogenetic noise can be transformed into evolutionary information for understanding character state transitions along species phylogenies.

关键词： Hemiplasy Multispecies coalescence Lineage sorting Gene tree discordance Phylotranscriptomics Allium subg.Cyathophora

Bird specimen number linked with species trait and climate niche breadth

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Avian Research 2024年第1期15卷 108-115页

作者： Xiaoyu Duan Xiongwei Huang Jingya Zhang Shuo Lv gang Song Yanping Wang gang Feng Ministry of Education Key Laboratory of Ecology and Resource Use of the Mongolian Plateau&Inner Mongolia Key Laboratory of Grassland Ecology School of Ecology and EnvironmentInner Mongolia UniversityHohhot010020China Key Laboratory of Marine Biotechnology of Fujian Province Institute of OceanologyCollege of Marine SciencesFujian Agriculture and Forestry UniversityFuzhou350002China Key Laboratory of Zoological Systematics and Evolution Institute of ZoologyChinese Academy of SciencesBeijing100101China Laboratory of Island Biogeography and Conservation Biology College of Life SciencesNanjing Normal UniversityNanjing210023China

Biological specimens are fundamental for taxonomy and flora/fauna *** importantly,they also play crucial roles in recording environmental impacts on morphology and behavior,which is vital for biodiversity research and ***,there are few systematic studies on the patterns and drivers of bird specimen number at regional *** study is the first attempt to examine the relationships between bird specimen number and species traits as well as climate niche breadth in China,aiming to answer two questions:1)how do species’temperature niche breadth and precipitation niche breadth influence specimen number?2)which trait is most associated with bird specimen number?The associations between bird specimen number and explanatory variables were examined using ordinary least squares,generalized linear models,phylogenetic generalized linear mixed models,and multiple *** results showed that Muscicapidae was the family with the highest specimen number,and Passeriformes was the order with the highest specimen *** specimen number significantly increased with larger temperature niche breadth and precipitation niche *** number was also positively associated with geographic range size,habitat specificity,hunting vulnerability and clutch size,but negatively associated with body *** findings suggest that future bird specimen collection should pay more attention to birds with limited ecological niches,large body sizes,and small clutch *** research enhances the use of bird specimen data to study and preserve biodiversity.

关键词： Biodiversity conservation Biological specimens Bird traits Scientific collection Specimen number Temperature and precipitation

Method for triangular fuzzy multiple attribute decision making based on two-dimensional density operator method

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Journal of Systems Engineering and Electronics 2024年第1期35卷 178-185页

作者： LIN Youliang LI Wu LIU gang HUANG Dong School of Economics and Management Hunan Institute of Science and TechnologyYueyang 414000China Hunan Vocational College for Nationalities Yueyang 414000China School of Information Science and Engineering Hunan Institute of Science and TechnologyYueyang 414000China

Aiming at the triangular fuzzy(TF)multi-attribute decision making(MADM)problem with a preference for the distribution density of attribute(DDA),a decision making method with TF number two-dimensional density(TFTD)operator is proposed based on the density operator theory for the decision maker(DM).Firstly,a simple TF vector clustering method is proposed,which considers the feature of TF number and the geometric distance of ***,the least deviation sum of squares method is used in the program model to obtain the density weight ***,two TFTD operators are defined,and the MADM method based on the TFTD operator is ***,a numerical example is given to illustrate the superiority of this method,which can not only solve the TF MADM problem with a preference for the DDA but also help the DM make an overall comparison.

关键词： fuzzy decision making clustering density operator multi-attribute decision making(MADM)

Progress on the glassy-crystal laminates:From design,microstructure to deformation and future solutions

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Journal of Materials Science & Technology 2024年第5期172卷 113-144页

作者： Yu Chen Ronggao Cui Jun Shen gang Wang College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518060China College of Physics and Optoelectronic Engineering Shenzhen UniversityShenzhen 518060China Department of Motor Design Business Weichai New Energy Technology Co.Ltd.Weifang 261061China Guangdong Key Laboratory of Electromagnetic Control and Intelligent Robots Shenzhen UniversityShenzhen 518060China Laboratory for Microstructures Institute of MaterialsShanghai UniversityShanghai 200444China

The development of new design strategies to create innovative structural materials,refine existing ones,and achieves compatible combinations of strength and plasticity remains a worldwide *** alloys,such as shape memory alloys(SMAs),bulk metallic glasses(BMGs),high entropy alloys(HEAs),and heterogeneous pure metals such as Cu,have excellent mechanical responses,but they still fall short of meeting all the requirements of structural materials due to specific flaws,such as lack of tensile de-formation for BMGs and low yielding strength for *** address these shortcomings,proposals such as integrating glassy matrices and crystallized alloys,such as HEAs/SMAs,have been ***,these solutions have unresolved issues,such as the challenging control of B2 phase formation in BMG ***,glass-crystal(A/C)laminated alloys with alternating layers have been reported to exhibit improved mechanical properties and activated work-hardening behaviors,but they still face press-ing issues such as bonding interfaces and unknown deformation *** review focuses on design routes such as the selection of alloy components and processing techniques,exploration of micro-structural evolution and deformation modes with an increase in strain,and future solutions to address pressing and unsolved *** prominent advantages include diversified deformation mechanisms,such as deformation twinning,martensitic phase transformation,and precipitation hardening,as well as tuned interactive reactions of shear bands(SBs)near the A/C ***,this review provides a promising pathway to design and develop structural materials in the materials field community.

关键词： Glassy-crystal laminates Bulk metallic glasses High entropy alloys Shape memory alloys Microstructure Deformation mechanisms Future solutions