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Tsinghua Science and Technology 2024年第1期29卷 1-12页

作者： yu Guan Pengceng Wen Jianqiang li Jinli zhang Xianghui Xie Faculty of Information Technology Beijing University of TechnologyBeijing 100124China Beijing Children’s Hospital Affiliated to Capital Medical University Beijing 100020China

UreteroPelvic Junction Obstruction(UPJO)is a common hydronephrosis disease in children that can result in an even progressive loss of renal *** is an economical,radiationless,noninvasive,and high noise preliminary diagnostic step for *** intelligence has been widely applied to medical fields and can greatly assist doctors'diagnostic *** demand for a highly secure network environment in transferring electronic medical data online,therefore,has led to the development of blockchain *** this study,we built and tested a framework that integrates a deep learning diagnosis model with blockchain *** diagnosis model is a combination of an attention-based pyramid semantic segmentation network and a discrete wavelet transformation-processed residual classification *** also compared the performance between benchmark models and our *** diagnosis model outperformed benchmarks on the segmentation task and classification task with MloU=87.93,MPA=93.52,and accuracy=91.77%.For the blockchain system,we applied the InterPlanetary File System protocol to build a secure and private sharing *** framework can automatically grade the severity of UPJO using ultrasound images,guarantee secure medical data sharing,assist in doctors'diagnostic ability,relieve patients'burden,and provide technical support for future federated learning and linkage of the Internet of Medical Things(loMT).

关键词： data mining image processing and computer vision machine learning medical information systems

Resource-saving scheduling scheme for centralized target tracking in multiple radar system under automatic blanket jamming

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Chinese Journal of Aeronautics 2024年第5期37卷 349-362页

作者： Zhengjie li yujie WEI Junwei XIE Haowei zhang yu TIAN Air and Missile Defense College Air Force Engineering UniversityXi’an 710051China Air Force Xi’an Flying College Xi’an 710300China Air and Missile Defense Institute Air Force Research InstituteBeijing 100085China School of Economics and Management Beihang UniversityBeijing 100191China

This paper investigates the problem of Joint Radar Node Selection and Power Allocation(JRNSPA)in the Multiple Radar System(MRS)in the blanket jamming *** radar node independently tracks moving target and subsequently transmits the raw observation data to the fusion center,which formulates a centralized tracking network *** order to establish a practical blanket jamming environment,we suppose that each target carries the self-defense jammer which automatically implements blanket jamming to the radar nodes that exceed the preset interception ***,the Predicted Conditional Cramer-Rao Lower Bound(PC-CRLB)is derived and utilized as the tracking accuracy *** at ensuring both the tracking performance and the Low Probability of Intercept(LPI)performance,the resource-saving scheduling model is formulated to minimize the transmit power consumption while meeting the requirements of tracking ***,the Modified Zoutendijk Method Of Feasible Directions(MZMFD)-based two-stage solution technique is adopted to solve the formulated non-convex optimization *** results show the effectiveness of the proposed JRNSPA scheme.

关键词： Multiple Radar System(MRS) Centralized target tracking Resource scheduling Blanket jamming Low Probability of Intercept(LPI)

Highly efficient photo-thermal synergistic catalysis of CO_(2)methanation over La_(1-x)Ce_(x)NiO_(3)perovskite-catalyst

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Nano Research 2024年第9期17卷 7945-7956页

作者： Ting li Zhen-yu zhang De-Cun Luo Bo-yu Xu Rong-Jiang zhang Ji-Long Yao Dan li Tao Xie Institute of Industrial Catalysis School of Chemical Engineering and TechnologyXi’an Jiaotong UniversityXi’an 710049China

Solar-driven photo-thermal catalytic CO_(2)methanation reaction is a promising technology to alleviate the problems posed by greenhouse gases ***,designing advanced photo-thermal catalysts remains a research challenge for CO_(2)methanation *** this work,a series of ABO3(A=lanthanide,B=transition metal)perovskite catalysts with Ce-substituted LaNiO3(La_(1-x)Ce_(x)NiO_(3),x=0,0.2,0.5,0.8,1)were synthesized for CO_(2)*** La_(0.2)Ce_(0.8)NiO_(3) exhibited the highest CH_(4) formation rate of 258.9 mmol·g^(-1)·hcat-1,CO_(2)conversion of 55.4%and 97.2%CH_(4) selectivity at 300℃with the light intensity of 2.9 W·cm^(-2).Then the catalysts were thoroughly analyzed by physicochemical structure and optical properties *** partial substitution of the A-site provided more active sites for the adsorption and activation of CO_(2)/H_(2).The sources of the active sites were considered to be the oxygen vacancies(O_(v))created by lattice distortions due to different species of ions(La^(3+),Ce^(4+),Ce^(3+))and exsolved Ni0 by H_(2)*** catalysts have excellent light absorption absorbance and low electron-hole(e^(-)/h^(+))recombination rate,which greatly contribute to the excellent performance in photo-thermal synergistic catalysis(PTC)CO_(2)*** results of in situ irradiated electron paramagnetic resonance spectrometer(ISI-EPR)and ISI-X-ray photoelectron spectroscopy(XPS)indicated that the aggregation of unpaired electrons near the defects and Ni metal(from La and Ce ions to Ov and Ni0)accelerated adsorption and activation of CO_(2)/H_(2).At last,the catalyst properties and structure were correlated with the proposed reaction mechanism from the in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)*** in situ precipitation of the B-site enhanced the dispersion of Ni,while its enriched photoelectrons upon illumination further promote hydrogen *** H^(*)spillover accelerated t

关键词： photo-thermal catalysis CO_(2)methanation perovskite A-site substitution in situ diffuse reflection infrared Fourier transform spectrum(DRIFTS)

Cyclodextrin nanofilms with hydrophobic and hydrophilic channels for solvent permeation and molecular sieving

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Nano Research 2024年第7期17卷 6638-6644页

作者： Kai zhang yu Dai Yongli Shi Zhaoxin zhang linji li Xiaojin zhang Fan Xia Faculty of Materials Science and Chemistry China University of GeosciencesWuhan 430074China Henan Academy of Geology Zhengzhou 450052China

Nanofilms that can fast permeate solvents and accurately sieve molecules are of significant importance for separation.A promising strategy is to align the inner cavities of macrocycles into the channels within nanofilms,and control the channel size by selecting the ***,the channels outside the macrocycles are ***,we prepare nanofilms with hydrophobic channels(cyclodextrin inner cavity)and hydrophilic channels(cyclodextrin outer space)through interfacial polymerization of azobenzene-4,4’-dicarbonyl dichloride and amino-functionalizedβ-*** utilizing the significant geometric changes caused by the photoisomerization of azobenzene,nanofilms with adjustable hydrophilic channel sizes were *** nanofilms have high permeability to polar and non-polar solvents,and can distinguish molecules with almost the same molecular weight but different *** work expands the development of next-generation nanofilms generated through interfacial polymerization by incorporating rational molecular design.

关键词： nanofilm β-cyclodextrin azobenzene interfacial polymerization solvent permeation molecular sieving

Application of GNSS-PPP on Dynamic Deformation Monitoring of Offshore Platforms

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China Ocean Engineering 2024年第2期38卷 352-361页

作者： yu li-na XIONG Kuan GAO Xi-feng li Zhi FAN li-long zhang Kai Institute of Ocean Energy and Intelligent Construction Tianjin University of TechnologyTianjin 300384China China Railway Construction Bridge Engineering Bureau Group Co.LTD Tianjin 300300China School of Civil Engineering Tianjin UniversityTianjin 300072China Department of Land Surveying and Geo-Informatics The Hong Kong Polytechnic UniversityHong KongChina State Key Laboratory of Precision Blasting Jianghan UniversityWuhan 430056China

The real-time dynamic deformation monitoring of offshore platforms under environmental excitation is crucial to their safe *** Global Navigation Satellite System-Precise Point Positioning(GNSS-PPP)has been considered for this purpose,its monitoring accuracy is relatively ***,the influence of background noise on the dynamic monitoring accuracy of GNSS-PPP remains ***,it is imperative to further validate the feasibility of GNSS-PPP for deformation monitoring of offshore *** address these concerns,vibration table tests with different amplitudes and frequencies are *** results demonstrate that GNSS-PPP can effectively monitor horizontal vibration displacement as low as±30 mm,which is consistent with ***,the spectral characteristic of background noise in GNSS-PPP is similar to that of GNSS-RTK(Real Time Kinematic).Building on this observation,an improved Complete Ensemble Empirical Mode Decomposition with Adaptive Noise(CEEMDAN)has been proposed to de-noise the data and enhance the dynamic monitoring accuracy of *** monitoring application research is also undertaken,successfully extracting and analyzing the dynamic deformation of an offshore platform structure under environmental excitation using GNSS-PPP monitoring in conjunction with improved CEEMDAN *** comparing the de-noised dynamic deformation trajectories of the offshore platform during different periods,it is observed that the platform exhibits reversible alternating vibration responses under environmental excitation,with more pronounced displacement deformation in the direction of load *** research results confirm the feasibility and potential of GNSS-PPP for dynamic deformation monitoring of offshore platforms.

关键词： GNSS-PPP offshore platform dynamic deformation monitoring improved CEEMDAN de-noising

Quantum support vector machine for multi classification

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Communications in Theoretical Physics 2024年第7期76卷 57-62页

作者： li Xu Xiao-yu zhang Ming li Shu-qian Shen College of Science China University of PetroleumQingdao 266580China

Classical machine learning algorithms seem to be totally incapable of processing tremendous data,while quantum machine learning algorithms could deal with big data unhurriedly and provide exponential acceleration over classical *** this paper,we propose two quantum support vector machine algorithms for multi *** is the quantum version of the directed acyclic graph support vector *** other one is to use the Grover search algorithm before measurement,which amplifies the amplitude of the phase storing of the classification *** k classification,the former provides quadratic reduction in computational complexity when *** latter accelerates the training speed significantly and more importantly,the classification result can be read out with a probability of at least 50%using only one *** conduct numerical simulations on two algorithms,and their classification success rates are 96%and 88.7%,respectively.

关键词： quantum support vector machine quantum feature mapping Grover search algorithm

Toward high performance microwave absorber by implanting La_(0.8)CoO_(3)nanoparticles on rGO

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Journal of Materials Science & Technology 2024年第7期174卷 176-187页

作者： li Chang yu-Ze Wang Xin-Ci zhang lin li Hua-zhang Zhai Mao-Sheng Cao Key Laboratory for Photonic and Electronic Bandgap Materials Ministry of EducationSchool of Physics&Electronic EngineeringHarbin Normal UniversityHarbin 150025China School of Materials Science and Engineering Beijing Institute of TechnologyBeijing 100081China

The advent of“intelligent era”brings our life more convenience,but the electromagnetic radiation sur-rounding us not only greatly threatens human health,also makes information leakage and hidden trouble to national defense ***,it is very urgent to develop novel electromagnetic wave absorption materials with lightweight,strong absorption,tunable absorption frequency and broad band ***,a novel electromagnetic wave absorber is obtained by constructing La_(0.8)CoO_(3)-rGO nanocompos-ite,where La_(0.8)CoO_(3)nanoparticles are anchored on graphene nanosheets by the electrostatic interaction between GO and La_(0.8)CoO_(3).The effect of hybridization ratio of La_(0.8)CoO_(3)and rGO on microwave ab-sorption properties is carefully *** optimal reflection loss of La_(0.8)CoO_(3)-rGO nanocomposite can reach-62.34 dB with the maximum effective bandwidth of 6.08 GHz,presenting 48.78%and 245.45%increment compared to bare La_(0.8)CoO_(3)nanoparticles,*** effective absorption bandwidth covers a broad electromagnetic wave absorption band from Ku band to the C band by tailoring thickness of the absorbers from 2.4 mm to 4.4 *** fascinating electromagnetic wave absorption performance is attributed to the synergy effect of La_(0.8)CoO_(3)and rGO,which integrates magnetic and dielectric loss caused by resonance,conductance,relaxation,and scattering *** result confirms that La_(0.8)CoO_(3)-rGO nanocomposite is potential candidates toward high-efficiency microwave absorbers and provides a valuable pathway for designing high-performance microwave attenuation materials in the future.

关键词： Perovskite La_(0.8)CoO_(3)nanoparticles Graphene Nanocomposite Microwave absorbing Broad band absorption

Attention Guided Multi Scale Feature Fusion Network for Automatic Prostate Segmentation

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Computers, Materials & Continua 2024年第2期78卷 1649-1668页

作者： yuchun li Mengxing Huang yu zhang Zhiming Bai School of Information and Communication Engineering Hainan UniversityHaikouChina College of Computer Science and Technology Hainan UniversityHaikouChina Urology Department Haikou Municipal People’s Hospital and Central South University Xiangya Medical College Affiliated HospitalHaikouChina School of Information Science and Technology Hainan Normal UniversityHaikouChina

The precise and automatic segmentation of prostate magnetic resonance imaging(MRI)images is vital for assisting doctors in diagnosing prostate *** recent years,many advanced methods have been applied to prostate segmentation,but due to the variability caused by prostate diseases,automatic segmentation of the prostate presents significant *** this paper,we propose an attention-guided multi-scale feature fusion network(AGMSF-Net)to segment prostate MRI *** propose an attention mechanism for extracting multi-scale features,and introduce a 3D transformer module to enhance global feature representation by adding it during the transition phase from encoder to *** the decoder stage,a feature fusion module is proposed to obtain global context *** evaluate our model on MRI images of the prostate acquired from a local *** relative volume difference(RVD)and dice similarity coefficient(DSC)between the results of automatic prostate segmentation and ground truth were 1.21%and 93.68%,*** quantitatively evaluate prostate volume on MRI,which is of significant clinical significance,we propose a unique *** essential performance evaluation and validation experiments have demonstrated the effectiveness of our method in automatic prostate segmentation.

关键词： Prostate segmentation multi-scale attention 3D Transformer feature fusion MRI

Synthetic Strategies of Carbon Nanobelts and Beyond

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Chemical Research in Chinese Universities 2024年第4期40卷 627-631页

作者： li Yanbang SHANG Wansong REN yu zhang Xi-Sha li Cheng zhang Guanxin zhang Deqing Beijing National Laboratory for Molecular Science CAS Key Laboratory for Organic SolidsInstitute of ChemistryChinese Academy of SciencesBeijing100190P.R.China University of Chinese Academy of Sciences Beijing100049P.R.China

Carbon nanobelts(CNBs)with aesthetically appealing molecular structures and outstanding physical properties have attracted more and more attentions from the scientific community due to their potential applications in synthetic materials,host-guest chemistry,optoelectronics,and so *** synthesis of CNBs at different stages was overviewed and some representative breakthroughs and advances in synthetic strategies were highlighted and *** key issue for the synthesis of CNBs is how to construct curved structures with high strain *** not only proposed a few unconventional CNBs as the promising target molecules,but also pointed out the bottom-up synthesis of conjugated tubular segments of carbon nanotubes sharing similar properties as carbon nanotubes is the next focus in this emerging area.

关键词： Carbon nanobelt Strain energy Carbon nanoring Single-walled carbon nanotube Bottom-up synthesis

Two-dimensional flow vector measurement based on all-fiber laser feedback frequency-shifted multiplexing technology

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Photonics Research 2024年第7期12卷 1371-1378页

作者： LEI zhang JIAliANG LV yuNKUN ZHAO JIE li KEYAN liU QI yu HONGTAO li BENli yu liANG LU Information Materials and Intelligent Sensing Laboratory of Anhui Province Anhui UniversityHefei 230601China Key Laboratory of Opto-Electronic Information Acquisition and Manipulation of Ministry of Education Anhui UniversityHefei 230601China School of Physics and Optoelectronic Engineering Anhui UniversityHefei 230601China School of Optics and Photonics Beijing Institute of TechnologyBeijing 100081China

The decomposition and identification of signals are crucial for flow vector acquisition in a multi-dimensional measurement. Here, we proposed a two-dimensional(2D) flow vector measurement system based on all-fiber laser feedback frequency-shifted multiplexing technology. The reliable performance of the system is characterized by experimental verification and numerical simulation. An orthogonal dual-beam structure is employed to eliminate the impact of an unknown incident angle in the practical application. Meanwhile, the vector velocity signals in 2D can be decomposed into one-dimensional(1D) scalar signals by adopting the frequency-shifted multiplexing,which makes it easy to obtain the vector information and velocity distribution of fluid motion through the self-mixing interference frequency spectrum.

关键词： fiber shifted flow