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Application of MAGnetic resonance imaging compilation in acute ischemic stroke

World Journal of Clinical Cases 2021年第35期9卷 10828-10837页

作者： Qi Wang Gang Wang Qiang sun Di-he sun Department of Radiology The Stroke Hospital of Liaoning ProvinceShenyang 110101Liaoning ProvinceChina

BACKGROUND Synthetic magnetic resonance imaging(MRI)MAGnetic resonance imaging compilation(MAGiC)is a new MRI *** T1,T2,T2-fluidattenuated inversion recovery(FLAIR)contrast images,quantitative images of T1 and T2 mapping,and MAGiC phase sensitive inversion recovery(PSIR)Vessel cerebrovascular images can be obtained simultaneously through post-processing at the same time after completing a *** recent years,studies have reported that MAGiC can be applied to patients with acute ischemic *** hypothesized that the synthetic MRI vascular screening scheme can evaluate the degree of cerebral artery stenosis in patients with acute ischemic *** To explore the application value of vascular images obtained by synthetic MRI in diagnosing acute ischemic *** A total of 64 patients with acute ischemic stroke were selected and examined by MRI in the current retrospective cohort *** scanning sequences included traditional T1,T2,and T2-FLAIR,three-dimensional time-of-flight magnetic resonance angiography(3D TOF MRA),diffusion-weighted imaging(DWI),and synthetic *** contrast images(T1,T2,and T2-FLAIR)and intracranial vessel images(MAGiC PSIR Vessel]were automatically reconstructed using synthetic MRI raw *** contrast-to-noise ratio(CNR)values of traditional T1,T2,and T2-FLAIR images and MAGiC reconstructed T1,T2,and T2-FLAIR images in DWI diffusion restriction areas were measured and *** PSIR Vessel and TOF MRA images were used to measure and calculate the stenosis degree of bilateral middle cerebral artery stenosis *** consistency of MAGiC PSIR Vessel and TOF MRA in displaying the degree of vascular stenosis with computed tomography angiography(CTA)was *** Among the 64 patients with acute ischemic stroke,79 vascular stenosis areas showed that the correlation between MAGiC PSIR Vessel and CTA(r=0.90,Pher than that between TOF MRA and CTA(r=0.84,P<0.01).With a degree of vas

关键词： Acute ischemic stroke Magnetic resonance imaging Magnetic resonance angiography Computed tomography angiography Phase sensitive inversion recovery

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Research on Multicloud Access Control Policy Integration Framework

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China Communications 2019年第9期16卷 222-234页

作者： Peng Zhao Lifa Wu Zheng Hong he sun Command&Control Engineering College Army Engineering University of PLANanjing 210007China School of Computer Science Nanjing University of Posts and TelecommunicationsNanjing 210023China PANDA Electronics Group Co. Ltd.Nanjing 210014China

Multicloud access control is important for resource sharing and security interoperability across different clouds,and heterogeneity of access control policy is an important challenge for cloud *** is widely used in distributed environment as a declaratively fine-grained,attribute-based access control policy language,but the policy integration of XACML lacks formal description and theory *** Access Control Policy Integration Framework(MACPIF)is proposed in the paper,which consists of Attribute-based Policy Evaluation Model(ABPEM),Four-value Logic with Completeness(FLC)and Four-value Logic based Policy Integration Operators(FLPIOs).ABPEM evaluates access control policy and extends XACML decision to *** to policy decision set and policy integration characteristics,we construct FLC and define FLPIOs including Intersection,Union,Difference,Implication and *** prove that MACPIF can achieve policy monotonicity,functional completeness,canonical suitability and canonical *** results show that this framework can meet the requirements of policy integration in Multicloud.

关键词： Multicloud access control policyintegration four-value logic

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Lithium Isotopic Geochemistry in Subduction Zones:Retrospects and Prospects

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Acta Geologica Sinica(English Edition) 2017年第2期91卷 688-710页

作者： WAN Hongqiong sun he LIU Haiyang XIAO Yilin CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026AnhuiChina

Subduction zones involve many complex geological processes, including the release of slabderived fluids, fluid/rock interactions, partial melting, isotopic fractionations, elemental transporting, and crust/mantle interactions. Lithium（Li） isotopes（~6Li and ~7Li） have relative mass difference up to 16%, being the largest among metal elements. Thus, Li isotopes have advantage to interprete trace various geological processes. Most importantly, during crust/mantle interactions in deep subduction zones, surface materials and mantle rocks usually have distinct Li isotopic compositions. Li isotopes can be potential tracer for subduction processes, from the onset of subduction to the release of Li from subducted slabs and interaction with mantle wedge, as well as the fate of Li in slab-derived fluids and residual slabs. Moreover, the Li isotopic composition of subducting output materials can provide useful information for understanding global Li circulation. With developments in measurement and expansion of Li isotopic database, Li isotopic geochemistry will provide more inference and be a powerful tracer for understanding subduction-related processes. This work retrospected the application of Li isotopes in tracing successive subduction processes, and made some prospects for further studies of Li isotopes.

关键词： subduction zone Li isotopes subduction-related processes Li geological tracer

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A Reconstruction Strategy for Fault Diagnosis Based on Fault Direction 36

A Reconstruction Strategy for Fault Diagnosis Based on Fault...

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第36届中国控制会议

作者： he sun Chunhui Zhao Youxisn sun Furong Gao State Key Laboratory of Industrial Control Technology College of Control Science and EngineeringZhejiang University Department of Chemical and Biomolecular Engineering The Hong Kong Uniwersity of Science and Technology

ISBN: (纸本)9781538629185

In the present work,a new iterative selection strategy and reconstruction modeling method is proposed for fault *** proposed algorithm can extract those informative fault directions which are responsible for the concerned alarming monitoring ***,the fault effects are decomposed in two different monitoring subspaces,principal subspace（PCS） and residual subspace（RS）.Then,the significance of each fault direction in both PCS and RS is evaluated by the proposed iterative fault directions selection strategy,and those informative ones are chosen for reconstruction *** proposed method provide an effective way of modeling the fault effects so as to correct the fault more *** feasibility and performance are illustrated with numerical simulation and the Tennessee Eastman（TE）benchmark process.

关键词： Iterative fault direction selection fault diagnosis fault reconstruction principal component analysis

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Steady-state response of a saturated half-space with an overlying dry layer subjected to a moving load

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2012年第1期13卷 33-43页

作者： An-feng HU Bo sun Kang-he XIE MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering Zhejiang University Hangzhou 310058 China

In this paper,the steady-state response of a saturated half-space with an overlying dry layer subjected to a moving rectangular load is *** governing partial differential equations are solved using the Fourier *** solutions in time-space domain are expressed in terms of infinite Fourier type integrals,which can be evaluated only by numerical *** results show that the influence of a drained or undrained interface on the response is related to the permeability of the underlying saturated ***,the effect due to the upper dry layer is associated with the thickness of the layer.

关键词： Steady-state response Moving load Saturated half-space Overlying dry layer Fourier transform Drained orundrained interface

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A Hadronic Model Calculation of the Electro-Production of the d^(*) Dibaryon

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Chinese Physics Letters 2001年第7期18卷 885-887页

作者： QING Di sun he-Ming WANG Fan Department of Physics Nanjing UniversityNanjing 210093 Institute of Modern Physics Southwest Jiaotong UniversityChengdu 610031

The electro production cross sections of ed→ed^(*) have been calculated based on the meson exchange current *** cross section around 30°of 1 GeV electron in the laboratory frame is about 10 nb,which is about two orders smaller than that of the quasi-elastic and Δ resonance production.A special kinematics and detector system must be studied to pin down the weak signal of d^(*) resonance from the strong background.

关键词： model resonance meson

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Effect of Oxalic Acid on Potassium Release from Typical Chinese Soils and Minerals

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Pedosphere 2007年第4期17卷 457-466页

作者： TU Shu-Xin GUO Zhi-Fen sun Jin-he College of Resources and Environment Huazhong Agricultural University Wuhan 430070 （China）. Institute of Nuclear Agricultural Sciences Zhejiang University Hangzhou 310029 （China）

Oxalic acid plays an important role in improving the bioavailability of soil nutrients. Batch experiments were employed to examine the influences of oxalic acid on extraction and release kinetics of potassium （K） from soils and minerals along with the adsorption and desorption of soil K^＋. The soils and minerals used were three typical Chinese soils, black soil （Mollisol）, red soil （Ultisol）, and calcareous alluvial soil （Entisol）, and four K-bearing minerals, biotite, phlogopite, muscovite, and microcline. The results showed that soil K extracted using 0.2 mol L^-1 oxalic acid was similar to that using 1 mol L^-1 boiling HNO3. The relation between K release （y） and concentrations of oxalic acid （c） could be best described logarithmically as y = a ＋ blogc, while the best-fit kinetic equation of K release was y = a ＋ b√t, where a and b are the constants and t is the elapsed time. The K release for minerals was ranked as biotite 〉 phlogopite 〉〉 muscovite 〉 microcline and for soils it was in the order： black soil 〉 calcareous alluvial soil 〉 red soil. An oxalic acid solution with low pH was able to release more K from weathered minerals and alkaline soils. Oxalic acid decreased the soil K^＋ adsorption and increased the soil K^＋ desorption, the effect of which tended to be greater at lower solution pH, especially in the red soil.

关键词： Chinese soils K^+ adsorption and desorption K-bearing minerals K release oxalic acid

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UNIFIED MODEL FOR SPLASH DROPLETS AND SUSPENDED MIST OF ATOMIZED FLOW

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Journal of Hydrodynamics 2008年第1期20卷 125-130页

作者： LIU Shi-he sun Xiao-fei LUO Jing State Key Laboratory of Water Resources and Hydropower Engineering Science Wuhan University Wuhan 430072 China

In this article, the unified mathematical model for splash droplets and suspended mist of atomized flow was established, which classifies the atomized sources into the splash source and the suspended source. For the splash source, the Lagrangian method was used to simulate the random motion of splash water droplets, and for the suspended source the theory of air-water two-phase flow was used to simulate the mist flow moving in particle clouds. The rainfall intensity of the atomized flow was obtained by summarizing the rainfall intensities relative to the above two types of atomized sources. Both experimental data and prototype observation data were used for the verification of the mathematical model. For both the distribution of rainfall intensity, and the outer edge of the atomized flow, the simulation results are in agreement with the experimental data or prototype observation data.

关键词： two phase flow atomized flow splash water drop suspended mist

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Molecular Dynamics Study of Effects of Si-Doping Upon Structure and Mechanical Properties of Carbon Nanotube

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Communications in Theoretical Physics 2006年第4期45卷 741-744页

作者： SONG Hai-Yang sun he-Ming ZHANG Guo-Xiang Department of Physics Beijing Institute of Technology Beijing 100081 China

In this paper, a Si-doped single-walled carbon nanotube （SWCNT）（7,7） and several perfect armchair SWCNTs are investigated using the classical molecular dynamics simulations method. The inter-atomic short-range interaction is represented by empirical Tersoff bond order potential. The computational results show that the axial Young＇s modulus of the perfect SWCNTs are in the range of 1.099 ± 0.005 TPa, which is in good agreement with the existing experimental results. From our simulation, the Si-doping decreases the Young＇s modulus of SWCNT, and with the increased strain levels, the effect of Si-doped layer in enhancing the local stress level increases. The Young＇s modulus of armchair SWCNTs are weakly affected by tube radius.

关键词： molecular dynamics simulation carbon nanotubes Young's modulus Si-doping

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Increased glacier melt enhances future extreme floods in the southern Tibetan Plateau

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Advances in Climate Change Research 2024年第3期15卷 431-441页

作者： he sun Tan-Dong YAO Feng-Ge SU Tinghai Ou Zhihua he Guoqiang TANG Deliang CheN State Key Laboratory of Tibetan Plateau Earth System Environment and Resources(TPESER)Institute of Tibetan Plateau ResearchChinese Academy of SciencesBeijing 100101China Regional Climate Group Department of Earth SciencesUniversity of GothenburgGothenburg 40530Sweden Centre for Hydrology University of SaskatchewanSaskatoon S7N 1K2Canada Climate and Global Dynamics National Center for Atmospheric ResearchBoulder CO 80307USA

Mountainous areas are of special hydrological concern because topography and atmospheric conditions can result in large and sudden floods,posing serious risks to water-related safety in neighbouring *** Yarlung Zangbo(YZ)River basin is the largest river basin on the Tibetan Plateau(TP),but how floods will discharge in this basin and how the role of glacier melt in floods will change throughout the 21st-century under shared socioeconomic pathways scenarios(SSP2-4.5 and SSP5-8.5)remain ***,we comprehensively address this scientific question based on a well-validated large-scale glacier-hydrology *** results indicate that extreme floods was projected to increase in the YZ basin,and was mainly reflected in increased duration(4–10 d per decade)and intensity(153–985 m^(3)s^(−1)per decade).Glacier runoff was projected to increase(2–30 mm per decade)throughout the 21st-century,but there was also a noticeable decrease or deceleration in glacier runoff growth in the late first half of the century under the SSP2-4.5,and in the latter half of the century under the *** melt was projected to enhance the duration(12%–23%)and intensity(15%–21%)of extreme floods under both SSPs,which would aggravate the impact of future floods on the socioeconomics of the YZ *** effect was gradually overwhelmed by precipitation-induced floods from glacier areas to YZ *** study takes the YZ basin as a projection framework example to help enrich the understanding of future flood hazards in basins affected by rainfall-or meltwater across the TP,and to help policy-makers and water managers develop future plans.

关键词： floods glacier Tibetan

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