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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)

Adaptive Event-Triggered Time-Varying Output Group Formation Containment Control of Heterogeneous Multiagent Systems

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IEEE/CAA Journal of Automatica Sinica 2024年第6期11卷 1398-1409页

作者： Lihong Feng Bonan Huang Jiayue Sun Qiuye Sun Xiangpeng xie College of Information Science and Engineering Northeastern UniversityShenyang 110819China College of Automation and College of Artificial Intelligence Nanjing University of Posts and TelecommunicationsNanjing 210023China IEEE

In this paper,a class of time-varying output group formation containment control problem of general linear hetero-geneous multiagent systems(MASs)is investigated under directed *** MAS is composed of a number of tracking leaders,formation leaders and followers,where two different types of leaders are used to provide reference trajectories for movement and to achieve certain formations,***,compen-sators are designed whose states are estimations of tracking lead-ers,based on which,a controller is developed for each formation leader to accomplish the expected ***,two event-triggered compensators are proposed for each follower to evalu-ate the state and formation information of the formation leaders in the same group,***,a control protocol is designed for each follower,utilizing the output information,to guide the output towards the convex hull generated by the forma-tion leaders within the ***,the triggering sequence in this paper is decomposed into two sequences,and the inter-event intervals of these two triggering conditions are provided to rule out the Zeno ***,a numerical simulation is intro-duced to confirm the validity of the proposed results.

关键词： Adaptive control event-triggered mechanisms for-mation containment(FC) heterogeneous multiagent systems time-varying group formation.

A novel box-counting method for quantitative fractal analysis of threedimensional pore characteristics in sandstone

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International Journal of Mining Science and Technology 2024年第4期34卷 479-489页

作者： Huiqing Liu Heping xie Fei Wu Cunbao Li Renbo Gao State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing UniversityChongqing 400030China School of Resources and Safety Engineering Chongqing UniversityChongqing 400030China Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Shenzhen UniversityShenzhen 518060China Shenzhen Key Laboratory of Deep Underground Engineering Sciences and Green Energy College of Civil and Transportation EngineeringShenzhen UniversityShenzhen 518060China

Fractal theory offers a powerful tool for the precise description and quantification of the complex pore structures in reservoir rocks,crucial for understanding the storage and migration characteristics of media within these *** with the challenge of calculating the three-dimensional fractal dimensions of rock porosity,this study proposes an innovative computational process that directly calculates the three-dimensional fractal dimensions from a geometric *** employing a composite denoising approach that integrates Fourier transform(FT)and wavelet transform(WT),coupled with multimodal pore extraction techniques such as threshold segmentation,top-hat transformation,and membrane enhancement,we successfully crafted accurate digital rock *** improved box-counting method was then applied to analyze the voxel data of these digital rocks,accurately calculating the fractal dimensions of the rock pore *** numerical simulations of permeability experiments were conducted to explore the physical correlations between the rock pore fractal dimensions,porosity,and absolute *** results reveal that rocks with higher fractal dimensions exhibit more complex pore connectivity pathways and a wider,more uneven pore distribution,suggesting that the ideal rock samples should possess lower fractal dimensions and higher effective porosity rates to achieve optimal fluid transmission *** methodology and conclusions of this study provide new tools and insights for the quantitative analysis of complex pores in rocks and contribute to the exploration of the fractal transport properties of media within rocks.

关键词： 3D fractal analysis Fractal dimension Rock pore structure Box-counting method Permeability simulation Computational geosciences

A DFT study on Pt single atom loaded COF for efficient photocatalytic CO_(2)reduction

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Journal of Materials Science & Technology 2024年第3期170卷 87-94页

作者： Fei xie Chuanbiao Bie Jian Sun Zhenyi Zhang Bicheng Zhu Laboratory of Solar Fuel Faculty of Materials Science and ChemistryChina University of GeosciencesWuhan430078China Key Laboratory of New Energy and Rare Earth Resource Utilization of State Ethnic Affairs Commission Key Laboratory of Photosensitive Materials and Devices of Liaoning ProvinceSchool of Physics and Materials EngineeringDalian Minzu UniversityDalian116600China

Photocatalytic CO_(2)reduction provides a promising strategy for the alleviation of greenhouse effect and energy shortage *** single atom modification is an effective method to improve the CO_(2)reduction performance of covalent organic framework(COF)photocatalysts,while the intrinsic mechanism is not revealed in ***,a Pt-COF photocatalytic system was constructed by embedding Pt single atom in TFPT-TMT-COF(TFPT:1,3,5-tris(4-formylphenyl)-triazine,TMT:2,4,6-trimethyl-1,3,5-triazine).Based on density functional theory(DFT)calculation,the geometric structure and electronic property of Pt-COF were investigated,and the CO_(2)adsorption and reduction reaction process on Pt-COF were *** results show that the Pt atom can be steadily anchored in COF via the formation of Pt-N and Pt-C ***,there is strong electronic interaction between Pt and *** incorporation of Pt atom benefits the CO_(2)reduction activity of COF from multiple aspects:(ⅰ)reducing the band gap and improving light absorption;(ⅱ)enhancing CO_(2)adsorption and activating the CO_(2)molecule;(ⅲ)decreasing the energy barrier in the hydrogenation step of CO_(2)→COOH,thus facilitating CO_(2)conversion to CO;(ⅳ)inhibiting the hydrogenation of CO,thereby increasing the selectivity of *** work brings a novel insight into the excellent CO_(2)reduction performance of Pt modified COF,and provides useful references for the design of single atom photocatalysts.

关键词： Photocatalysis Carbon dioxide reduction Covalent organic framework Pt single atom Theoretical calculation

Characterization of size-resolved effective density of atmospheric particles in an urban atmosphere in Southern China

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Journal of Environmental Sciences 2024年第7期141卷 194-204页

作者： Tingting xie Liming Cao Jinyi Zheng Peng Xuan Xiaofeng Huang Laboratory of Atmospheric Observation Supersite School of Environment and EnergyPeking University Shenzhen Graduate SchoolShenzhen 518055China

Effective density(ρ_(eff))is one of the most important physical properties of atmospheric particles,providing important references in exploring the emissions and aging processes of fresh *** this study,a combined system of differential mobility analyzer,centrifugal particle mass analyzer,and condensation particle counter was used to periodically measure theρ_(eff)of atmospheric particles in Shenzhen from Oct.2021 to *** showed that theρ_(eff)of particles with various size presented a bimodal distribution,which could be divided into main density(ρ_(m),main peak,corresponding to relatively dense particles after aging)and sub density(ρ_(s),sub peak,corresponding to fresh particles).The occurrence frequencies ofρ_(s)of particles with diameters of 50 and 80 nm were less than 20%,but were as high as about 40%of that with diameters from 120 to 350 ***ρ_(m)showed increasing trend with the size of particles,whileρ_(s)decreased as the increasing of the size of ***ρ_(eff)on pollution day varied significantly with chemical *** increasing of the proportion of sulfate could promote the increasing ofρ_(eff),while black carbon and organic matter caused opposite effects,which may be related to various factors,including the difference of the material density and morphology of various chemical ***ρ_(eff)of 50,80 and 120 nm particles decreased considerably during the new particle formation event,indicating that organic condensation was an important contributor to new particle growth.

关键词： DMA-CPMA-CPC Effective density Main/sub density Size distribution

Design of low-alloying and high-performance solid solution-strengthened copper alloys with element substitution for sustainable development

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International Journal of Minerals,Metallurgy and Materials 2024年第5期31卷 826-832页

作者： Jiaqiang Li Hongtao Zhang Jingtai Sun Huadong Fu Jianxin xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Advanced Materials Processing(MOE) University of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation University of Science and Technology BeijingBeijing 100083China Liaoning Academy of Materials Shenyang 110004China

Solid solution-strengthened copper alloys have the advantages of a simple composition and manufacturing process,high mechanical and electrical comprehensive performances,and low cost;thus,they are widely used in high-speed rail contact wires,electronic component connectors,and other *** the contradiction between low alloying and high performance is an important challenge in the development of solid solution-strengthened copper *** the typical solid solution-strengthened alloy Cu-4Zn-1Sn as the research object,we proposed using the element In to replace Zn and Sn to achieve low alloying in this *** new alloys,Cu-1.5Zn-1Sn-0.4In and Cu-1.5Zn-0.9Sn-0.6In,were designed and *** total weight percentage content of alloying elements decreased by 43%and 41%,respectively,while the product of ultimate tensile strength(UTS)and electrical conductivity(EC)of the annealed state increased by 14%and 15%.After cold rolling with a 90%reduction,the UTS of the two new alloys reached 576 and 627MPa,respectively,the EC was 44.9%IACS and 42.0%IACS,and the product of UTS and EC(UTS×EC)was 97%and 99%higher than that of the annealed state *** dislocations proliferated greatly in cold-rolled alloys,and the strengthening effects of dislocations reached 332 and 356 MPa,respectively,which is the main reason for the considerable improvement in mechanical properties.

关键词： element substitution copper alloy solid solution strengthening microstructure and performance

Design and optimization of a greener sinomenine hydrochloride preparation process considering variations among different batches of the medicinal herb

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Chinese Journal of Chemical Engineering 2024年第7期71卷 77-90页

作者： Dandan Ren Jiale xie Tianle Chen Haibin Qu Xingchu Gong Pharmaceutical Informatics Institute College of Pharmaceutical SciencesZhejiang UniversityHangzhou 310058China National Key Laboratory of Chinese Medicine Modernization Zhejiang UniversityHangzhou 310058China Jinhua Institute of Zhejiang University Jinhua 321016China

The current methods used to industrially produce sinomenine hydrochloride involve several issues,including high solvent toxicity,long process flow,and low atomic utilization efficiency,and the greenness scores of the processes are below 65 *** solve these problems,a new process using anisole as the extractant was *** exhibits high selectivity for sinomenine and can be connected to the subsequent water-washing *** alkalization of the medicinal material,heating extraction,water washing,and acidification crystallization were carried *** process was modeled and *** design space was *** recommended operating ranges for the critical process parameters were 3.0–4.0 h for alkalization time,60.0–80.0℃ for extraction temperature,2.0–3.0(volume ratio)for washing solution amount,and 2.0–2.4 mol·L^(-1) for hydrochloric acid *** new process shows good robustness because different batches of medicinal materials did not greatly impact crystal purity or sinomenine transfer *** sinomenine transfer rate was about 20%higher than that of industrial *** greenness score increased to 90 points since the novel process proposed in this research solves the problems of long process flow,high solvent toxicity,and poor atomic economy,better aligning with the concept of green chemistry.

关键词： Sinomenine hydrochloride Process optimization Anisole

Multilayer polyethylene separator with enhanced thermal properties for safe lithium-ion batteries Author links open overlay panel

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Particuology 2024年第8期91卷 29-37页

作者： Ying Jiang Chen Sun Feilong Dong Haiming xie Liqun Sun National&Local United Engineering Laboratory for Power Battery Department of ChemistryNortheast Normal UniversityChangchun130024China

The separator plays an important part in battery safety and *** separators are widely used in commercial Lithium-ion batteries(LIBs),owing to their excellent properties,but they suffer from serious thermal shrinkage and poor electrolyte ***,a multilayer separator(ASPESA)is developed by coating two thin layers of low-density polyethylene(LDPE)and Al_(2)O_(3)on both sides of a polyethylene membrane using a facile and environmentally friendly casting *** ASPESA separator demonstrates a shutdown function at 120℃and shows enhanced thermal stability under 185℃,with a small thermal shrinkage of 1%.Meanwhile,the LDPE and Al_(2)O_(3)layers can improve the electrolyte wettability and electrolyte uptake(407.23%).The multilayer ASPESA separator delivers an excellent cycle performance in LiFePO_(4)||Li cells with a discharge capacity of 144.5 mAh g^(-1)after 900 cycles,with a high-capacity retention of 98.9%(compared to the 5th cycle).Therefore,the multilayer ASPESA separator has great utilization potential as a high-safety separator in LIBs.

关键词： Low-density polyethylene microspheres Al_(2)O_(3)particles Thermal shutdown High safety Lithium-ionbatteries

Deep Learning Blockchain Integration Framework for Ureteropelvic Junction Obstruction Diagnosis Using Ultrasound Images

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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

Application of Optical Hydrogels in Environmental Sensing

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Energy & Environmental Materials 2024年第3期7卷 311-336页

作者： Shuo Yang Shruti Sarkar Xing xie Dan Li Jianmin Chen Shanghai Key Laboratory of Atmospheric Particle Pollution and Prevention(LAP3) Department of Environmental Science and EngineeringFudan UniversityShanghai 200438China School of Civil and Environmental Engineering Georgia Institute of TechnologyAtlanta Georgia 30332USA

The ever-increasing complexity of environmental pollutants urgently warrants the development of new detection *** based on the optical properties of hydrogels enabling fast and easy in situ detection are attracting increasing *** this paper,the data from 138 papers about different optical hydrogels(OHs)are extracted for statistical *** detection performance and potential of various types of OHs in different environmental pollutant detection scenarios were evaluated and compared to those obtained using the standard detection *** on this analysis,the target recognition and sensing mechanisms of two main types of OHs are reviewed and discussed:photonic crystal hydrogels(PCHs)and fluorescent hydrogels(FHs).For PCHs,the environmental stimulus response,target receptors,inverse opal structures,and molecular imprinting techniques related to PCHs are reviewed and ***,the different types of fluorophores(i.e.,compound probes,biomacromolecules,quantum dots,and luminescent microbes)of FHs are ***,the potential academic research directions to address the challenges of applying and developing OHs in environmental sensing are proposed,including the fusion of various OHs,introduction of the latest technologies in various fields to the construction of OHs,and development of multifunctional sensor arrays.

关键词： environmental sensors fluorescent hydrogel optical hydrogel photonic crystal hydrogel pollution detection