检索结果-南通市图书馆

An Intelligent Framework for Resilience Recovery of FANETs with Spatio-Temporal Aggregation and Multi-Head Attention Mechanism

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computers, Materials & Continua 2024年第5期79卷 2375-2398页

作者： Zhijun Guo yun Sun YingWang Chaoqi Fu Jilong zhong Air Traffic Control and Navigation College Air Force Engineering UniversityXi’an710000China Institute of Systems Engineering Academy of Military ScienceBeijing100101China Equipment Management and UAV Engineering College Air Force Engineering UniversityXi’an710038China Defense Innovation Institute Academy of Military ScienceBeijing100071China

Due to the time-varying topology and possible disturbances in a conflict environment,it is still challenging to maintain the mission performance of flying Ad hoc networks(FANET),which limits the application of Unmanned Aerial Vehicle(UAV)swarms in harsh *** paper proposes an intelligent framework to quickly recover the cooperative coveragemission by aggregating the historical spatio-temporal network with the attention *** mission resilience metric is introduced in conjunction with connectivity and coverage status information to simplify the optimization model.A spatio-temporal node pooling method is proposed to ensure all node location features can be updated after destruction by capturing the temporal network *** with the corresponding Laplacian matrix as the hyperparameter,a recovery algorithm based on the multi-head attention graph network is designed to achieve rapid *** results showed that the proposed framework can facilitate rapid recovery of the connectivity and coverage more effectively compared to the existing *** results demonstrate that the average connectivity and coverage results is improved by 17.92%and 16.96%,respectively compared with the state-of-the-art ***,by the ablation study,the contributions of each different improvement are *** proposed model can be used to support resilient network design for real-time mission execution.

关键词： Resilience cooperative mission FANET spatio-temporal node pooling multi-head attention graph network

X-ray-activated Bi^(3+)/Pr^(3+)co-doped LiYGeO_4 phosphor with UV and NIR dual-emissive persistent luminescence

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Rare Earths 2024年第5期42卷 955-961,I0005页

作者： Xianggui Yin Hongyun zhong Lin Liu Junpeng Shi Xia Sun yun Zhang State Key Laboratory of Structural Chemistry Fujian Institute of Research on the Structure of MatterChinese Academy of SciencesFuzhou350002China Xiamen Key Laboratory of Rare Earth Photoelectric Functional Materials Xiamen Institute of Rare Earth MaterialsHaixi InstituteChinese Academy of SciencesXiamen361021China Fujian Science and Technology Innovation Laboratory for Optoelectronic Information of China Fuzhou350108China

X-ray-activated luminescence materials have broad application prospects in photodynamic therapy of deep *** them,X-ray-activated persistent luminescence materials(PLMs)exhibiting multiple emission peaks have drawn extensive attention for the ir capacity to achieve a combination of bioimaging and therapeutic ***,we developed a novel PLM,LiYGeO_4:Bi^(3+),Pr^(3+),that simultaneously exhibits UV and NIR dual persistent luminescence(PersL)emissions after irradiation by *** material can be re peatedly excited by X-ray and emits similar lumine scence intensity every time,which shows good PersL *** addition,LiYGeO_4:Bi^(3+),Pr^(3+)exhibits photostimulated PersL properties by stimulation with a red light-emitting diode(LED)or NIR laser after long-term *** work provides a new choice of X-ray-excited PLMs with UV and NIR dual emission and the novel phosphor shows promise as a potential candidate for the integration of treatment and diagnosis of deep tumors.

关键词： Co-doping X-ray-activated Dual emissions Persistent luminescence Rare earths

Effects of the sand content of muddy water content on one-dimensional vertical infiltration characteristics and dense layer formation characteristics

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

International Journal of Agricultural and Biological Engineering 2024年第1期17卷 172-179页

作者： Shouxuan Kang Liangjun Fei yun zhong Lihua Liu State Key Laboratory of Eco-hydraulics in Northwest Arid Region Xi’an University of TechnologyXi’an 710048China Institute of Water Resources and Hydro-electric Engineering Xi’an University of TechnologyXi’an 710048China Engineering Research Center of Eco-environment in Three Gorges Reservoir Region Ministry of EducationChina Three Gorges UniversityYichang 443002HubeiChina School of Water Conservancy and Hydroelectric Power Hebei University of EngineeringHandan 056038HebeiChina

Muddy water irrigation,an effective water-saving irrigation method,has been widely used in the Yellow River Basin in *** investigate the effect of sand content on water infiltration and dense layer formation under one-dimensional vertical infiltration of muddy water,muddy water infiltration experiments were performed in the laboratory,and five sand contents of muddy water(S=0%,3%,6%,9%,and 12%)were *** were established to describe the relationship between the cumulative infiltration amount[I(t)]and the infiltration duration(t);the relationship among the migration distance of the wetting front(Z),S,and t;the thickness of the sedimentary layer[H(t)];and the relationship between S and *** results revealed that I(t)and Z decreased significantly with the increase of sand contents,while H(t)increased significantly with the increase of sand contents.I(t)and Z were in the range of 7 cm and 20 cm for each treatment,*** variation in I(t)with t fitted Kostiakov and Philip models,and the coefficients of determination were all greater than *** the increase in S,the infiltration coefficient gradually decreased,the infiltration index gradually increased,and the sorptivity gradually *** particle composition of the sedimentary layer was similar to that of the argillaceous sediment,and the content of particles with a size of less than 2 mm in the sedimentary layer was lower than that of the argillaceous *** with the original soil,the content of particles with a size of less than 0.05 mm and physical clay particles(diameter less than 0.01 mm)in the soil with an infiltration depth of 0-2 cm *** retention layer was from the topsoil to the infiltration depth of approximately 2 *** study can provide a scientific basis for further research on soil infiltration mechanisms under muddy water.

关键词： muddy water sand content dense layer cumulative infiltration wetting front transport deposit layer thickness

MPI/OpenMP-Based Parallel Solver for Imprint Forming Simulation

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Computer Modeling in Engineering & Sciences 2024年第7期140卷 461-483页

作者： Yang Li Jiangping Xu yun Liu Wen zhong Fei Wang School of Mechanical Engineering Jiangsu UniversityZhenjiang212016China School of Mechanical Engineering Wuhan Polytechnic UniversityWuhan430023China Shenyang Mint Company Limited Shenyang110092China

In this research,we present the pure open multi-processing(OpenMP),pure message passing interface(MPI),and hybrid MPI/OpenMP parallel solvers within the dynamic explicit central difference algorithm for the coining process to address the challenge of capturing fine relief features of approximately 50 *** such precision demands the utilization of at least 7 million tetrahedron elements,surpassing the capabilities of traditional serial programs previously *** mitigate data races when calculating internal forces,intermediate arrays are introduced within the OpenMP *** helps ensure proper synchronization and avoid conflicts during parallel ***,in the MPI implementation,the coins are partitioned into the desired number of *** division allows for efficient distribution of computational tasks across multiple *** simulation examples are conducted to compare the three solvers with serial programs,evaluating correctness,acceleration ratio,and parallel *** results reveal a relative error of approximately 0.3%in forming force among the parallel and serial solvers,while the predicted insufficient material zones align with experimental ***,speedup ratio and parallel efficiency are assessed for the coining process *** pureMPI parallel solver achieves a maximum acceleration of 9.5 on a single computer(utilizing 12 cores)and the hybrid solver exhibits a speedup ratio of 136 in a cluster(using 6 compute nodes and 12 cores per compute node),showing the strong scalability of the hybrid MPI/OpenMP programming *** approach effectively meets the simulation requirements for commemorative coins with intricate relief patterns.

关键词： Hybrid MPI/OpenMP parallel computing MPI OpenMP imprint forming

Super-high bed sintering for iron ores:problems ascertainment

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Iron and Steel Research International 2024年第5期31卷 1063-1070页

作者： Liang-ping Xu Hui-bo Liu Yu-chao Zhao Qiang zhong zhong-lin Dong Guang-hui Li Tao Jiang School of Minerals Processing and Bioengineering Central South UniversityChangsha410083HunanChina

Super-high bed sintering process is an important development direction of iron ore sintering for its lower emission and higher ***,there is a lack of deep understanding of the uneven quality of super-high bed sintering products,and the deterioration of reduction disintegration performance,the thickening of hearth layer and the reduction in energy-saving effect are perplexing enterprises and *** ascertain the problems of super-high bed sintering,ten sintering machines with the areas of 265,280,360,550 and 660 m^(2)and bed depth above 900 mm were sampled and *** results showed that problems were mainly shown in the unevenness of chemical composition,macrostructure,mechanical strength and metallurgical *** chemical composition exhibits severe segregation in both horizontal and vertical directions,with basicity segregation reaching as high as *** uneven macrostructure of sinter is reflected in a 10%difference in porosity and mechanical strength increase in 16%–19%along the vertical *** reducibility and reduction disintegration performance gradually deteriorate along the bed depth,with a difference of 10.5%in reducibility and 7.3%in RDI−0.5 mm(reduction disintegration index of sinter with size smaller than 0.5 mm).

关键词： Super-high bed sintering Uneven sinter performance Segregation Agglomeration Iron ore

In vivo 3-photon fluorescence microscopy of white matter in mouse brain excited at the 1700 nm window

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Innovative Optical Health Sciences 2024年第5期17卷 81-87页

作者： Jie Huang Jincheng zhong Shen Tong Yingxian Zhang ping Qiu Ke Wang Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province College of Physics and Optoelectronic EngineeringShenzhen UniversityShenzhen 518060P.R.China School of Medical Information and Engineering Xuzhou Medical UniversityXuzhou 221004P.R.China

White matter,a densely packed collection of myelinated axons,plays an essential part in neural *** high spatial resolution and deep penetration,multi-photon microscopy(MPM)is promising for white matter imaging in animal models in *** third harmonic generation(THG)signal can be generated from white matter,but the bottom part of the white matter layer generates weak THG due to its high ***,we demonstrate an in vivo labeling and imaging technology,capable of visualizing the white matter layer in the mouse brain,combining°uorescence labeling with MitoTracker Red and three-photon°uorescence(3PF)microscopy excited at the 1700 nm window.3PF signals are several times higher than THG signals,resulting in deeper imaging of the white matter layer with the *** results indicate that 3PF microscopy is a promising technology for white matter imaging in the deep brain in vivo.

关键词： Three-photon microscopy white matter myelin MitoTracker Red

Research on thermal insulation materials properties under HTHP conditions for deep oil and gas reservoir rock ITP-Coring

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Petroleum Science 2024年第4期21卷 2625-2637页

作者： Zhi-Qiang He He-ping Xie Ling Chen Jian-ping Yang Bo Yu Zi-Jie Wei Ming-zhong Gao State Key Laboratory of Intelligent Construction and Healthy Operation and Maintenance of Deep Underground Engineering College of Water Resource and Hydropower Sichuan University Guangdong Provincial Key Laboratory of Deep Earth Sciences and Geothermal Energy Exploitation and Utilization Institute of Deep Earth Sciences and Green Energy College of Civil and Transportation Engineering Shenzhen University School of Mechanical Engineering Sichuan University College of Polymer Science and Engineering Sichuan University

Deep oil and gas reservoirs are under high-temperature conditions, but traditional coring methods do not consider temperature-preserved measures and ignore the influence of temperature on rock porosity and permeability, resulting in distorted resource assessments. The development of in situ temperaturepreserved coring(ITP-Coring) technology for deep reservoir rock is urgent, and thermal insulation materials are key. Therefore, hollow glass microsphere/epoxy resin thermal insulation materials(HGM/EP materials) were proposed as thermal insulation materials. The materials properties under coupled hightemperature and high-pressure(HTHP) conditions were tested. The results indicated that high pressures led to HGM destruction and that the materials water absorption significantly increased; additionally,increasing temperature accelerated the process. High temperatures directly caused the thermal conductivity of the materials to increase; additionally, the thermal conduction and convection of water caused by high pressures led to an exponential increase in the thermal conductivity. High temperatures weakened the matrix, and high pressures destroyed the HGM, which resulted in a decrease in the tensile mechanical properties of the materials. The materials entered the high elastic state at 150.C, and the mechanical properties were weakened more obviously, while the pressure led to a significant effect when the water absorption was above 10%. Meanwhile, the tensile strength/strain were 13.62 MPa/1.3%and 6.09 MPa/0.86% at 100.C and 100 MPa, respectively, which meet the application requirements of the self-designed coring device. Finally, K46-f40 and K46-f50 HGM/EP materials were proven to be suitable for ITP-Coring under coupled conditions below 100.C and 100 MPa. To further improve the materials properties, the interface layer and EP matrix should be optimized. The results can provide references for the optimization and engineering application of materials and thus technical su

关键词： Deep oil and gas reservoir rock In situ temperature-preserved coring (ITP-Coring) Hollow glass microsphere/epoxy resin thermal insulation materials (HGM/EP materials) High-temperature and high-pressure (HTHP) Physical and mechanical properties

A Possible X-ray Quasi-periodic Oscillation in the Narrow-line Seyfert 1 Galaxy Mrk 142

同方期刊数据库评论

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Research in Astronomy and Astrophysics 2024年第6期24卷 191-200页

作者： Xiao-Gu zhong Jian-Cheng Wang Yong-yun Chen Xiao-Ling Yu College of Physics and Electronic Engineering Qujing Normal UniversityQujing 655011China yunnan Observatories Chinese Academy of SciencesKunming 650216China

A possible quasi-periodic oscillation(QPO) at frequency 7.045 × 10^(-5) Hz is found in the narrow-line Seyfert 1galaxy Mrk 142 in the data of XMM-Newton collected on 2020 April *** find that the QPO signal is statistically significantly larger than the 5σ level and highly coherent with quality factor Q > 5 at the 0.3–10 keV band by using the method of the Lomb–Scargle Periodogram,the Weighted Wavelet Z-transform and the *** analyze the data in 0.3–0.6 keV,0.6–1 keV,1–3 keV and 3–10 keV energy bands,and find obvious QPO signals at 0.3–0.6 keV and 1–3 keV *** then analyze the time-average spectra and time variability at the QPO frequency of 7.045 × 10^(-5) Hz,and use a model to fit *** find that the QPO signal mainly comes from the X-ray hot corona.

关键词： X-rays:galaxies galaxies:Seyfert accretion accretion disks radiation mechanisms:general

Placenta-derived mesenchymal stem cells attenuate secondary brain injury after controlled cortical impact in rats by inhibiting matrix metalloproteinases

维普期刊数据库

同方期刊数据库评论

在线全文

学校读者我要写书评

暂无评论

BIOCELL 2024年第1期48卷 149-162页

作者： ping YANG YUANXIANG LAN zhong ZENG YAN WANG HECHUN XIA Department of Neurosurgery School of Clinical MedicineNingxia Medical UniversityYinchuanChina Key Laboratory of Ningxia Stem Cell and Regenerative Medicine General Hospital of Ningxia Medical UniversityYinchuanChina Department of Neurosurgery Xi’an International Medical Center HospitalXi’anChina

Background:As a form of biological therapy,placenta-derived mesenchymal stem cells(PDMSCs)exhibit considerable promise in addressing the complex pathological processes of traumaticbrain injury(TBI)due to their multi-target and multi-pathway mode of ***&Methods:This study investigates the protective mechanisms and benefits of PDMSCs in mitigating the effects of controlled cortical impact(CCI)in rats and glutamate-induced oxidative stress injury in HT22 cells in *** primary objective is to provide evidence supporting the clinical application of ***:In the in vivo arm of our investigation,we observed a swift elevation of matrix metalloproteinase-9(MMP-9)in the proximal cortex of injured brain tissues after ***,distinguished by their heightened expression of metalloproteinase tissue inhibitors-1 and-2(TIMP-1 and TIMP-2):were intravenously administered via the caudal *** intervention yielded significant reductions in the permeability of the blood-brain barrier(BBB):the extent of brain edema,the levels of inflammatory cytokines IL-1βand TNF-αin damaged brain tissue,and the activation status of microglia in CCI-afflicted *** the realm of in vitro experiments,PDMSC-conditioned media demonstrated substantial reductions in mortality rates and cleaved caspase-3 levels in glutamate-induced HT22 cells compared with conventional ***,this advantage was negated upon the introduction of neutralizing antibodies targeting TIMP-1 and ***:Collectively,our findings underscore the potential of PDMSCs in alleviating oxidative stress injury and secondary brain injury in the pathological process of TBI.

关键词： Traumatic brain injury Mesenchymal stem cells Oxidative stress Matrix metalloproteinases