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Scale effect removal and range migration correction for hypersonic target coherent detection

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Journal of Systems Engineering and Electronics 2024年第1期35卷 14-23页

作者： WU shang SUN Zhi jiang Xingtao ZHANG Haonan DENG jiangyun LI Xiaolong CUI Guolong School of Information and Communication Engineering University of Electronic Science and Technology of ChinaChengdu 611731China

The detection of hypersonic targets usually confronts range migration(RM)issue before coherent integration(CI).The traditional methods aiming at correcting RM to obtain CI mainly considers the narrow-band radar condition.However,with the increasing requirement of far-range detection,the time bandwidth product,which is corresponding to radar’s mean power,should be promoted in actual application.Thus,the echo signal generates the scale effect(SE)at large time bandwidth product situation,influencing the intra and inter pulse integration performance.To eliminate SE and correct RM,this paper proposes an effective algorithm,i.e.,scaled location rotation transform(ScLRT).The ScLRT can remove SE to obtain the matching pulse compression(PC)as well as correct RM to complete CI via the location rotation transform,being implemented by seeking the actual rotation angle.Compared to the traditional coherent detection algorithms,Sc LRT can address the SE problem to achieve better detection/estimation capabilities.At last,this paper gives several simulations to assess the viability of ScLRT.

关键词： hypersonic target detection coherent integration(CI) scale effect(SE)removal range migration(RM)correction scaled location rotation transform(ScLRT)

TransTM:A device-free method based on time-streaming multiscale transformer for human activity recognition

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Defence Technology（防务技术） 2024年第2期32卷 619-628页

作者： Yi Liu Weiqing Huang shang jiang Bobai Zhao Shuai Wang Siye Wang Yanfang Zhang Institute of Information Engineering Chinese Academy of Sciences School of Cyber SecurityUniversity of Chinese Academy of SciencesBeijingChina School of Information Management Beijing Information Science and Technology UniversityBeijingChina

RFID-based human activity recognition(HAR)attracts attention due to its convenience,noninvasiveness,and privacy protection.Existing RFID-based HAR methods use modeling,CNN,or LSTM to extract features effectively.Still,they have shortcomings:1)requiring complex hand-crafted data cleaning processes and 2)only addressing single-person activity recognition based on specific RF signals.To solve these problems,this paper proposes a novel device-free method based on Time-streaming Multiscale Transformer called TransTM.This model leverages the Transformer's powerful data fitting capabilities to take raw RFID RSSI data as input without pre-processing.Concretely,we propose a multiscale convolutional hybrid Transformer to capture behavioral features that recognizes singlehuman activities and human-to-human interactions.Compared with existing CNN-and LSTM-based methods,the Transformer-based method has more data fitting power,generalization,and scalability.Furthermore,using RF signals,our method achieves an excellent classification effect on human behaviorbased classification tasks.Experimental results on the actual RFID datasets show that this model achieves a high average recognition accuracy(99.1%).The dataset we collected for detecting RFID-based indoor human activities will be published.

关键词： Human activity recognition RFID Transformer

Approaching the uniaxiality of magnetic anisotropy in singlemolecule magnets

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Science China Chemistry 2023年第3期66卷 683-702页

作者： Chen Wang Yin-Shan Meng shang-da jiang Bing-Wu Wang Song Gao School of Chemistry Chemical Engineering and Life ScienceWuhan University of TechnologyWuhan 430070China Beijing National Laboratory of Molecular Science Beijing Key Laboratory for Magnetoeletric Materials and DevicesCollege of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China State Key Laboratory of Fine Chemicals Dalian University of TechnologyDalian 116024China Spin-X Institute School of Chemistry and Chemical EngineeringState Key Laboratory of Luminescent Materials and DevicesGuangdong-Hong Kong-Macao Joint Laboratory of Optoelectronic and Magnetic Functional MaterialsSouth China University of TechnologyGuangzhou 510641China

Single-molecule magnets(SMMs),which can exhibit slow magnetization relaxation and bulk-magnet-like hysteresis of purely molecular origin,are promising candidates for high-density information storage,molecular spintronics,and quantum computing.To realize their applications,it is crucial to improve the blocking temperature(TB)and the effective relaxation barrier(Ueff).Three decades of multidisciplinary research have yielded distinct SMMs with a state-of-the-art Ueff of up to 2,000 K and a TB of up to the liquid nitrogen region.Several strategies have been investigated and summarized,which revealed that enhancing the uniaxiality of magnetic anisotropy is critical for constructing high-performance SMMs.Therefore,magnetic anisotropy,a key property that connects the molecular structure symmetry and performance of SMMs,plays a fundamental role in dictating magneto-structural correlations.Understanding and employing magnetic anisotropy would be significantly beneficial for rationally designing high-performance SMMs.This review focuses on the magnetic anisotropy of SMMs.We illustrate the origin and manifestation of magnetic anisotropy in mononuclear 3d-and 4f-block metal complexes.We then introduce developed approaches to investigate magnetic anisotropy both theoretically and experimentally.Typical SMMs by optimizing uniaxial magnetic anisotropy through lanthanide metallocene,symmetry controlling,and low-coordination approaches are represented.Furthermore,the remaining challenges and opportunities in this field will be discussed.

关键词： single-molecule magnets magnetic anisotropy uniaxiality lanthanide

Differences in and factors controlling organic matter enrichment in the Ziliujing Formation shale in the Sichuan Basin

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Petroleum Science 2024年第1期21卷 77-86页

作者： Peng Li Zhong-Bao Liu He Bi Tao jiang Rui-Kang Bian Peng-Wei Wang Xiao-Yu shang State Key Laboratory of Shale Oil and Gas Enrichment Mechanisms and Efficient Development Beijing102206China Key Laboratory of Shale Oil/Gas Exploration and Production Technology SINOPECBeijing102206China Petroleum Exploration and Production Research Institute SINOPECBeijing102206China Research Institute of Petroleum Exploration and Development PetroChinaBeijing100083China Chinese Academy of Geological Sciences Beijing100037China No.4 Oil Production Plant in daqing Oilfield Co Ltd. Daqing163511HeilongjiangChina

Lacustrine shale oil and gas are important fields for unconventional exploration and development in China,and organic-rich shale deposition lays down the critical foundation for hydrocarbon generation.There are two sets of shale,the Dongyuemiao and da’anzhai Members,in the Ziliujing Formation in the Sichuan Basin.To identify the differential enrichment characteristics of organic matter and clarify its controlling factors,geochemical analyses of organic and inorganic geochemical analyses were performed.The results showed that the total organic carbon content of the Dongyuemiao shale(1.36%)is slightly higher than that of the da’anzhai shale(0.95%).The enrichment of organic matter in the two shales resulted from the comprehensive controls of paleoproductivity,paleoenvironment,and terrigenous input,but different factors have different effects.In addition,driven by climate,the change in the sulfate concentration in the bottom water further led to the different intensities of bacterial sulfate reduction in early diagenesis.This made a great difference regarding organic matter accumulation in the two members.In general,climate may have played a dominant role in organic matter enrichment in the two sets of shale.

关键词： Lacustrine shale Ziliujing Formation Sichuan Basin Enrichment mechanism of organic matter

Exogenous calcium enhances the physiological status and photosynthetic capacity of rose under drought stress

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Horticultural Plant Journal 2024年第3期10卷 853-865页

作者： Xiaojuan Zhao shang Lin Shuang Yu Yichang Zhang Lin Su Lifang Geng Chenxia Cheng Xinqiang jiang College of Landscape Architecture and Forestry Qingdao Agricultural UniversityQingdaoShandong 266000China College of Horticultural Qingdao Agricultural UniversityQingdaoShandong 266000China

Drought(water shortage)can substantially limit the yield and economic value of rose plants(Rosa spp.).Here,we characterized the effect of exogenous calcium(Ca^(2+))on the antioxidant system and photosynthesis-related properties of rose under polyethylene glycol 6000(PEG6000)-induced drought stress.Chlorophyll levels,as well as leaf and root biomass,were significantly reduced by drought;drought also had a major effect on the enzymatic antioxidant system and increased concentrations of reactive oxygen species.Application of exogenous Ca^(2+)increased the net photosynthetic rate and stomatal conductance of leaves,enhanced water-use efficiency,and increased the length and width of stomata following exposure to drought.Organ-specific physiological responses were observed under different concentrations of Ca^(2+).Application of 5 mmol·L^(-1)Ca^(2+)promoted photosynthesis and antioxidant activity in the leaves,and application of 10 mmol·L^(-1)Ca^(2+)promoted antioxidant activity in the roots.Application of exogenous Ca^(2+)greatly enhanced the phenotype and photosynthetic capacity of potted rose plants following exposure to drought stress.Overall,our findings indicate that the application of exogenous Ca^(2+)enhances the drought resistance of roses by promoting physiological adaptation and that it could be used to aid the cultivation of rose plants.

关键词： Rosa hybrida L. Exogenous calcium Drought stress Physiological index Photosynthetic capacity

Investigation on the vortical structures by the Liutex method in turbulent channels at Re_(τ)=180 with scalloped and triangular riblet control

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Journal of Hydrodynamics 2024年第1期36卷 35-52页

作者： Zhang-dan Yu shang jiang Hai-dong Yu Bi-yu Pang Xin Dong Yi-qian Wang School of Mathematical Sciences Soochow UniversitySuzhou215006China Beijing Institute of Astronautical System Engineering Beijing100076China

Riblets are a series of small protrusions formed along the flow direction,which have been extensively studied as a passive turbulent drag reduction technique.Experiments and numerical simulations have shown that well-designed riblets can significantly reduce drag in turbulent flows,making them highly promising and valuable for various applications.In this study,we focus on a scalloped riblet,which is designed by smoothly connecting two third-order polynomials,and thus the sharpness of the tip and the curvature of the valley can be well defined.We conduct direct numerical simulations of turbulent channel with smooth plate,scalloped riblet-mounted and triangular riblet-mounted walls.Width in wall units of W^(+)=20 and height-width ratio ofγ=0.5 are selected for both riblet cases.Compared with the smooth plate case,the scalloped riblet case achieves an 8.68%drag reduction,while the triangular riblet case achieves a 4.79%drag reduction.The obtained drag reduction rate of the triangular riblet is consistent with previous experiments and simulations,and the results indicate that the scalloped riblet is more effective in reducing drag and deserves further investigation.We compare turbulent statistics of the scalloped riblet case with those of the triangular riblet case.The mean velocity profiles of riblets are similar,but both the Reynolds shear stress and second-order statistics of velocity fluctuations and Liutex are significantly reduced in the scalloped riblets controlled turbulent channel,indicating that the scalloped riblet can more effectively suppress the spanwise and wall-normal turbulent intensity near the wall.We also compare the pre-multiplied spectra of streamwise velocity and streamwise Liutex component for the three cases to investigate the energy distribution and characteristics of Liutex distribution.The Liutex vortex identification method is also utilized to analyze the instantaneous flow field,which provides insights into the flow field and could be beneficial for the further optimization of riblet.

关键词： Liutex vector riblet drag reduction tip sharpness turbulent channel scalloped

CircPMS1 promotes proliferation of pulmonary artery smooth muscle cells,pulmonary microvascular endothelial cells,and pericytes under hypoxia

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Animal Models and Experimental Medicine 2024年第3期7卷 310-323页

作者： Xiaoyi Hu shang Wang Hui Zhao Yaqin Wei Ruowang Duan Rong jiang Wenhui Wu Qinhua Zhao Sugang Gong Lan Wang Jinming Liu Ping Yuan Department of Cardio-Pulmonary Circulation Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghaiChina Institute of Bismuth Science University of Shanghai for Science and TechnologyShanghaiChina Department of Geriatrics Shanghai Institute of GeriatricsHuadong HospitalFudan UniversityShanghaiChina Department of Anesthesiology Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghaiChina

Background:Circular RNAs(circRNAs)have been recognized as significant regulators of pulmonary hypertension(PH);however,the differential expression and function of circRNAs in different vascular cells under hypoxia remain unknown.Here,we identified co-differentially expressed circRNAs and determined their putative roles in the proliferation of pulmonary artery smooth muscle cells(PASMCs),pulmonary microvascular endothelial cells(PMECs),and pericytes(PCs)under hypoxia.Methods:Whole transcriptome sequencing was performed to analyze the differential expression of circRNAs in three different vascular cell types.Bioinformatic analysis was used to predict their putative biological function.Quantitative real-time polymerase chain reaction,Cell Counting Kit-8,and EdU Cell Proliferation assays were carried out to determine the role of circular postmeiotic segregation 1(circPMS1)as well as its potential sponge mechanism in PASMCs,PMECs,and PCs.Results:PASMCs,PMECs,and PCs exhibited 16,99,and 31 differentially expressed circRNAs under hypoxia,respectively.CircPMS1 was upregulated in PASMCs,PMECs,and PCs under hypoxia and enhanced the proliferation of vascular cells.CircPMS1may upregulate DEP domain containing 1(DEPDC1)and RNA polymerase II subunit D expression by targeting microRNA-432-5p(miR-432-5p)in PASMCs,upregulate MAX interactor 1(MXI1)expression by targeting miR-433-3p in PMECs,and upregulate zinc finger AN1-type containing 5(ZFAND5)expression by targeting miR-3613-5p in PCs.Conclusions:Our results suggest that circPMS1 promotes cell proliferation through the miR-432-5p/DEPDC1 or miR-432-5p/POL2D axis in PASMCs,through the miR-433-3p/MXI1 axis in PMECs,and through the miR-3613-5p/ZFAND5 axis in PCs,which provides putative targets for the early diagnosis and treatment of PH.

关键词： circular postmeiotic segregation 1 circular RNAs hypoxia pulmonary hypertension vascular cells

Comparing the efficacy and safety of low,medium,and high dosages of selexipag for treating pulmonary hypertension:A systematic review and meta-analysis

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Animal Models and Experimental Medicine 2024年第1期7卷 56-70页

作者： shang Wang Yi Yan Jian Zhang Ping Yuan Ci-Jun Luo Hong-Ling Qiu Hui-Ting Li Jian Xu Lan Wang Tian-Lan Li Rong jiang Department of Cardio-Pulmonary Circulation Shanghai Pulmonary HospitalSchool of MedicineTongji UniversityShanghaiChina Heart Center and shanghai Institute of Pediatric Congenital Heart Disease Shanghai Children's Medical CenterNational Children's Medical CenterShanghai Jiaotong University School of MedicineShanghaiChina Department of Respiratory and Critical Care Medicine The 416 Hospital of Nuclear IndustryThe Second Affiliated Hospital of Chengdu Medical CollegeChengduChina Department of Hematology The Affiliated Hospital of Qingdao UniversityQingdaoChina

Background:The maintenance dosage of selexipag is categorized as low,medium or high.In order to assess the efficacy and safety of different dosages of selexipag for the risk stratification of pulmonary arterial hypertension(PAH),we performed a sys-tematic review and meta-analysis.Methods:Studies assessing PAH risk stratification indices,such as the World Health Organization functional class(WHO-FC),six-minute walk distance(6MWD),N-terminal pro-B-type natriuretic peptide(NT-proBNP)level,right atrial pressure(RAP),cardiac index(CI)and mixed venous oxygen saturation(SvO2),were included.Results:Thirteen studies were included.Selexipag led to improvements in the 6MWD(MD:24.20 m,95%CI:10.74-37.67),NT-proBNP(SMD:-0.41,95%CI:-0.79-0.04),CI(MD:0.47 L/min/m^(2),95%CI:0.17-0.77)and WHO-FC(OR:0.564,95%CI:0.457-0.697).Subgroup analysis demonstrated that all three dosages improved the 6MWD.A moderate dosage led to improvements in the CI(MD:0.30 L/min/m^(2),95%CI:0.15-0.46)and WHO-FC(OR:0.589,95%CI:0.376-0.922).Within 6 months of treatment,only the WHO-FC and CI were significantly improved(OR:0.614,95%CI:0.380-0.993;MD:0.30 L/min/m^(2),95%CI:0.16-0.45,respectively).More than 6 months of treatment significantly improved the 6MWD,WHO-FC and NT-proBNP(MD:40.87 m,95%CI:10.97-70.77;OR:0.557,95%CI:0.440-0.705;SMD:-0.61,95%CI:-1.17-0.05,respectively).Conclusions:Low,medium,and high dosages of selexipag all exhibited good effects.When treatment lasted for more than 6 months,selexipag exerted obvious effects,even in the low-dosage group.This finding is important for guiding individualized treatments.

关键词： individualized treatments meta-analysis prostacyclin receptor agonist risk stratification systematic review

分子视角下的电子自旋——自旋化学开拓合成化学科学前沿

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中国科学：化学 2024年第3期54卷 277-286页

作者：蒋尚达高松付雪峰华南理工大学自旋科技研究院广州511442 中山大学化学学院广州510275 北京大学化学与分子工程学院北京100871 国家自然科学基金委员会化学科学学部北京100085

本文从化学过程和分子材料的自旋效应、分子自旋材料新物态、分子自旋诊疗药物以及自旋化学理论计算等方面介绍了自旋化学的概念和研究领域,并对自旋化学面临的挑战和未来的重点研究方向进行了讨论.

关键词：交叉学科自旋化学分子磁性自旋效应自旋材料