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Multiscale observation in wide-spatial radar surveillance based on coherent FDA design

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Science China(Information Sciences) 2024年第2期67卷 232-252页

作者： Lei yu Feng he Yi SU College of Electronics Science National University of Defense Technology

Wide-spatial radar surveillance missions are challenging tasks, requiring an increased power budget and agility in transmission aimed at extracting information from multiple targets in different environments. These requirements necessitate high transmitting degrees of freedom(DoF) to achieve the objective of multiscale observation for specific tasks in specialized reg.ons of interest. herein, we exploit the multiscale observation ability in wide-spatial radar surveillance based on frequency diverse array(FDA)radar. The proposed method facilitates spatial anisotropic control of multiple radar resources, including the transmitting waveforms, beampattern, and bandwidth. By utilizing a coherent FDA radar, we offer principles for the selection of baseband waveforms, in addition to the quantitative design of the beampattern gain and optimal bandwidth from the perspective of detection. The feasibility of the proposed method is validated through numerical experiments, thus indicating the potential in wide-spatial radar surveillance. Moreover,this work can be regarded as a preliminary attempt to gauge the efficacy of the computational array, a novel academic concept.

关键词： multi-scale observation wide-spatial surveillance frequency diverse array (FDA) beampattern synthesis frequency diversity gain computational array

graphSTgAN:Situation understanding network of slow-fast high maneuvering targets for maritime monitor services of IoT data

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Digital Communications and Networks 2024年第3期10卷 620-630页

作者： guanlin Wu Haipeng Wang yu Liu You he Shenzhen International graduate School Tsinghua UniversityShenzhen518071China Institute of Space Science and Applied Technology Harbin Institute of TechnologyShenzhen518055China Department of Electronic Engineering Tsinghua UniversityBeijing100084China

With the rapid g.owth of the maritime Internet of Things(IoT)devices for Maritime Monitor Services(MMS),maritime traffic controllers could not handle a massive amount of data in *** unmanned MMS,one of the key technologies is situation ***,the presence of slow-fast high maneuvering targets and track breakages due to radar blind zones make modeling the dynamics of marine multi-agents difficult,and pose significant challenges to maritime situation *** order to comprehend the situation accurately and thus offer unmanned MMS,it is crucial to model the complex dynamics of multi-agents using IoT big ***,previous methods typically rely on complex assumptions,are plagued by unstructured data,and disregard the interactions between multiple agents and the spatial-temporal correlations.A deep learning model,graph Spatial-Temporal generative Adversarial Network(graphSTgAN),is proposed in this paper,which uses graph neural network to model unstructured data and uses STgAN to learn the spatial-temporal dependencies and *** experiments show the effectiveness and robustness of the proposed method.

关键词： Internet of things Multi-agents graph neural network Maritime monitoring services

Copper-mediated assembly of So_(2)F g.oup via radical fluorine-atom transfer strategy

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Chinese Chemical Letters 2024年第9期35卷 4-5页

作者： yu-yu Tan Lin-heng he Wei-Min he School of Electrical Engineering University of South ChinaHengyang 421001China

Because of the unique reactivity of sulfonyl fluoride(So_(2)F)g.oup,such compound has found increasing applications in the areas of organic synthesis,new drug development,pesticide,material science and click chemistry,*** is of current interest to develop novel strategies and methods for the facile preparation of sulfonyl fluorides in a green and highly efficient manner[1,2].Although the traditional approach for the synthesis of sulfonyl fluorides relies on the nucleophilic substitution of fluoride atom with sulfonyl chlorides.

关键词： fluoride synthesis fluorine

Chemotherapy induces breast cancer stem cell enrichment through repression of glutathione S-transferase Mu

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genes & Diseases 2024年第2期11卷 528-531页

作者： Jing he Yiran yu Yilin he Jie he guangyu Ji Haiquan Lu The Second Hospital and Advanced Medical Research Institute Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Department of Nursing The First Affiliated Hospital of Shandong First Medical UniversityJinanShandong 250014China School of Medicine Xinjiang Medical UniversityUrumqiXinjiang 830054China School of Medicine Binzhou Medical UniversityYantaiShandong 264003China oncology Department Jinan Zhangqiu District People's HospitalJinanShandong 250200China Key Laboratory for Experimental Teratology of the Ministry of Education Cheeloo College of MedicineShandong UniversityJinanShandong 250012China Center for Reproductive Medicine Shandong UniversityJinanShandong 250012China

Triple-negative breast cancer(TNBC)has aggressive characteristics as exemplified by the high risk of recurrence,metastasis,and patient mortality.1 Cytotoxic chemotherapy may reduce tumor burden initially,but leave behind chemo-resistant breast cancer stem cells(BCSCs)that lead to tumor recurrence and metastasis.2 Chemotherapy induces BCsC enrichment through the activation of glutathione biosynthesis pathways,which increases intracellular glutathione levels and specifies the BCSC phenotype through complicated downstream signaling pathways.3 glutathione S-transferases(gSTs),a superfamily(which contains seven cytosolic classes:Alpha,Kappa,Mu,omega,Pi,Theta,and Zeta,and one microsomal class MgSTs)of phase Il enzymes that catalyze the conjugation of glutathione with electrophilic compounds,play a critical role in detoxification and chemotherapy resistance of cancer ***,the role of gSTs in the regulation of BCSCs is largely elusive.

关键词： chemotherapy breast metastasis

A novel and promising engineering application of carbon dots:Enhancing the chloride binding performance of cement

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Chinese Chemical Letters 2024年第6期35卷 409-416页

作者： Wu-Jian Long Yang yu Chuang he guang.ong Provincial Key Laboratory of Durability for Marine Civil Engineering Key Lab of Coastal Urban Resilient InfrastructureMOECollege of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Corrosion of reinforcement induced by chloride invasion is extensively considered as the dominating deterioration mechanism of reinforced concrete(RC)structures,leading to serious safety hazards and tremendous economic ***,it still lacks well dispersive and cost-efficient nanomaterials to improve the anti-chloride-corrosion ability of RC ***,specific carbon dots(CDs)with high dispersity and low cost are deliberately designed,successfully prepared by hydrothermal processing,and then firstly applied to immensely enhance chloride binding performance of cement,thereby contributing to suppressing the corrosion of ***,the tailored CDs are composed of the carbon core with highly crystalline sp^(2)C structures and oxygen-containing g.oups connecting.on the carbon core;The typical equilibrium test confirms that with respect to that of the blank cement paste,the chloride binding capacity of cement paste involving 0.2 wt%(by weight of cement)CDs is increased by 109% after 14-day exposure to 3 mol/L Na Cl solution;according to comprehensive analyses of phase compositions,the chloride binding mechanism of CDs-modified cement is rationally attributed to the fact that the incorporation of CDs advances the formation of calcium silicate hydrate(C-S-H)gels and Friedel's salt(Fs),thus enormously enhancing the physically adsorbed and chemically bound chloride ions of cement *** work not only firstly provides a novel high-dispersity and low-cost nanomaterial toward the durability enhancement of RC structures,but also broadens the application of CDs in the field of engineering,conducing to stimulating their industrialization development.

关键词： Carbon dots Chloride binding Cement Chloride binding mechanism Friedel’s salt

Room-temperature ferroelectricity in van der Waals SnP_(2)S_(6)

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Frontiers of physics 2024年第4期19卷 113-123页

作者： Chaowei he Jiantian Zhang Li gong Peng yu State Key Laboratory of optoelectronic Materials and Technologies guangzhou Key Laboratory of Flexible Electronic Materials and Wearable Devices Nanotechnology Research Center School of Materials Science and EngineeringSun Yat-sen UniversityGuangzhou 510275China Instrumental Analysis and Research Center Sun Yat-sen UniversityGuangzhou 510275China

Two-dimensional(2D)ferroelectric materials,which possess electrically switchable spontaneous polarization and can be easily integrated with semiconductor technologies,is of utmost importance in the advancement of high-integration low-power *** the experimental discovery of certain 2D ferroelectric materials such as CuInP2S6 and In2Se3,achieving stable ferroelectricity at room temperature in these materials continues to present a significant ***,stable ferroelectric order at room temperature in the 2D limit is demonstrated in van der Waals SnP_(2)S_(6) atom layers,which can be fabricated via mechanical exfoliation of bulk SnP_(2)S_(6) *** polarization is observed in thin SnP_(2)S_(6) of~7 ***,a van der Waals ferroelectric field-effect transistor(Fe-FET)with ferroelectric SnP_(2)S_(6) as top-gate insulator and ptype WTe0.6Se1.4 as the channel was designed and fabricated successfully,which exhibits a clear clockwise hysteresis loop in transfer characteristics,demonstrating ferroelectric properties of SnP_(2)S_(6) atomic *** addition,a multilayer graphene/SnP_(2)S_(6)/multilayer graphene van der Waals vertical heterostructure phototransistor was also fabricated successfully,exhibiting improved optoelectronic performances with a responsivity(R)of 2.9 A/W and a detectivity(D)of 1.4×10^(12) *** results show that SnP_(2)S_(6) is a promising 2D ferroelectric material for ferroelectric-integrated low-power 2D devices.

关键词： two-dimensional ferroelectric materials ferroelectric fieldeffect transistors photodetectors

Comparative Transcriptome Analysis of Shell-Matrix-Protein genes and observation of the Shell Microstructure in the Deep-Sea Clam Calyptogena marissinica

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Journal of ocean University of China 2024年第3期23卷 797-810页

作者： SHI yu LIU Dongting YAo g.oyou he Maoxian CAS Key Laboratory of Tropical Marine Bio-Resources and Ecology Guangdong Provincial Key Laboratory of Applied Marine BiologySouth China Sea Institute of OceanologyChinese Academy of SciencesGuangzhou 510301China Southern Marine Science and Engineering guang.ong Laboratory(guangzhou) Guangzhou 511458China University of Chinese Academy of Sciences Beijing 100049China

The deep-sea clam Calyptogena marissinica is widely distributed in the Haima cold seep ecosystem on the northwes-tern slope of the South China Sea with low pH values,low temperature and high *** information is available on the biomineralization of this *** this research,we generated a comprehensive transcript dataset of ***’s mantle tissue,and a total of 19821 unigenes were *** shell matrix proteins(SMP)-related genes were *** qPCR results showed that four out of six prismatic matrix genes(MSP2,MSP5,prisilkin-39,and shematrin),four out of the six nacreous matrix genes(perlucin,pif,pif97,and papilin),and two extrapallial fluid proteins(SPARC and calmodulin)were significantly expressed in the *** the nacreous and the prismatic layers are chrysanthemum-shaped,which are stacked on the top of each other to form a laminated nacreous *** alignment and phylogenetic analysis of MSP-5,Prisilkin-39,Perlucin,and Pif homologues showed that some amino acids of *** that differed from those detected in other molluscs may cause the different shape of the nacreous and prismatic layers,but do not lead to a change in the species’evolutionary *** results indicated the conservation of the functions of SMP-related genes in ***,and the specific shape of the prismatic and nacreous layers of this deep-sea mollusc,which will contribute to the research on the molecular regulation mechanisms of biomineralization in *** and provide a new perspective to investigate biomineralization in deep-sea clams in general.

关键词： transcriptome biomineralization mantle tissue shell Calyptogena marissinica

Spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice in multiple dimensions during 1979 to 2020

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Acta oceanologica Sinica 2024年第3期43卷 102-114页

作者： yu g.o Xiaoli Wang he Xu Xiyong Hou CAS Key Laboratory of Coastal Environmental Processes and Ecological Remediation Yantai Institute of Coastal Zone ResearchChinese Academy of SciencesYantai 264003China Shandong Key Laboratory of Coastal Environmental Processes Yantai 264003China University of Chinese Academy of Sciences Beijing 100049China

Arctic sea ice is broadly regarded as an indicator and amplifier of g.obal climate *** rapid changes in Arctic sea ice have been widely ***,the spatiotemporal changes in the horizontal and vertical dimensions of Arctic sea ice and its asymmetry during the melt and freeze seasons are rarely quantified simultaneously based on multiple sources of the same long time *** this study,the spatiotemporal variation and freeze-thaw asymmetry of Arctic sea ice were investigated from both the horizontal and vertical dimensions during 1979–2020 based on remote sensing and assimilation *** results indicated that Arctic sea ice was declining at a remarkably high rate of–5.4×10^(4) km^(2)/a in sea ice area(SIA)and–2.2 cm/a in sea ice thickness(SIT)during 1979 to 2020,and the reduction of SIA and SIT was the largest in summer and the smallest in ***,compared with other sub-reg.ons,SIA showed a sharper declining trend in the Barents Sea,Kara Sea,and East Siberian Sea,while SIT presented a larger downward trend in the northern Canadian Archipelago,northern greenland,and the East Siberian *** to the seasonal trend of sea ice on sub-reg.on scale,the reduction rate of SIA exhibited an apparent spatial heterogeneity among seasons,especially in summer and winter,i.e.,the sub-reg.ons linked to the open ocean exhibited a higher decline rate in winter;however,the other sub-reg.ons blocked by the coastlines presented a greater decline rate in *** SIT,the sub-reg.ons such as the Beaufort Sea,East Siberian Sea,Chukchi Sea,Central Arctic,and Canadian Archipelago always showed a higher downward rate in all ***,a striking freeze-thaw asymmetry of Arctic sea ice was also *** sea ice changes in different dimensions,sea ice over most reg.ons in the Arctic showed an early retreat and rapid advance in the horizontal dimension but late melting and gradual freezing in the vertical *** amount of sea ice me

关键词： Arctic sea ice sea ice area sea ice thickness spatiotemporal variation freeze-thaw asymmetry

Dynamic Update Scheme of Spectrum Information Based on Spectrum opportunity Incentive in the Database-Assisted Dynamic Spectrum Management

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China Communications 2024年第3期21卷 75-90页

作者： Zhang yu Chen Yong he Panfeng Cai yueming Sixty-third Research Institute National University of Defense TechnologyNanjing 210007China College of Communications Engineering Army of Engineering UniversityNanjing 210007China

To solve the problem of delayed update of spectrum information(SI) in the database assisted dynamic spectrum management(DB-DSM), this paper studies a novel dynamic update scheme of SI in DB-DSM. Firstly, a dynamic update mechanism of SI based on spectrum opportunity incentive is established, in which spectrum users are encouraged to actively assist the database to update SI in real time. Secondly, the information update contribution(IUC) of spectrum opportunity is defined to describe the cost of accessing spectrum opportunity for heterogeneous spectrum users, and the profit of SI update obtained by the database from spectrum allocation. The process that the database determines the IUC of spectrum opportunity and spectrum user selects spectrum opportunity is mapped to a Hotelling model. Thirdly, the process of determining the IUC of spectrum opportunities is further modelled as a Stackelberg game by establishing multiple virtual spectrum resource providers(VSRPs) in the database. It is proved that there is a Nash Equilibrium in the game of determining the IUC of spectrum opportunities by VSRPs. Finally, an algorithm of determining the IUC based on a genetic algorithm is designed to achieve the optimal IUC. The-oretical analysis and simulation results show that the proposed method can quickly find the optimal solution of the IUC, and ensure that the spectrum resource provider can obtain the optimal profit of SI update.

关键词： database-assisted dynamic spectrum management Hotelling information updating contribution spectrum information updating Stackelberg