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Assessment of the effect of three-dimensional mantle density heterogeneity on Earth rotation in tidal frequencies

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Geodesy and Geodynamics 2016年第6期7卷 396-405页

作者： Lanbo Liu benjamin f.chao Wenke Sun Weijia Kuang Center for Integrative Geosciences University of Connecticut Institute of Earth Sciences Academia Sinica School of Earth Sciences University of Chinese Academy of Sciences Goddard Space flight Center NASAGreenbelt

In this paper, we report the assessment of the effect of the three-dimensional （3D） density heterogeneity in the mantle on Earth orientation parameters （EOP）（i.e., the polar motion, or PM, and the length of day, or LOD） in the tidal frequencies. The 3D mantle density model is estimated based upon a global S-wave velocity tomography model （S16U6LS） and the mineralogical knowledge derived from laboratory experiment. The lateral density variation is referenced against the preliminary reference earth model （PREM）. Using this approach the effects of the heterogeneous manHe density variation in all three tidal frequencies （zonal long periods, tesseral diurnal, and sectorial semidiurnal） are estimated in both PM and LOD. When compared with mass or density perturbations originated on the Earth＇s surface such as the oceanic and barometric changes, the het- erogeneous mantle contributes less than 10% of the total variation in PM and LOD in tidal frequencies. However, this is the gap that has not been explained to close the gap of the observation and modeling in PM and LOD. By computing the PM and LOD caused by 3D heterogeneity of the mantle during the period of continuous space geodetic measure- ment campaigns （e.g., CONT94） and the contribution from ocean tides as predicted by tide models derived from satellite altimetry observations （e.g., TOPEX/Poseidon} in the same period, we got the lump-sum values of PM and LOD. The computed total effects and the observed PM and LOD are generally agree with each other. In another word, the difference of the observed PM and LOD and the model only considering ocean tides, at all tidal frequencies （long periods, diurnals, and semidiurnals） contains the contributions of the lateral density heterogeneity of the mantle. Study of the effect of mantle densityheterogeneity effect on torque-free Earth rotation may provide useful constraints to construct the reference earth model （REM）, which is the next major objective in global geophysics resea

关键词： Polar motionLength of dayTidal frequencyMantle densityLateral heterogeneitySeismic tomography

On rotational normal modes of the Earth：Resonance,excitation,convolution, deconvolution and all that

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Geodesy and Geodynamics 2017年第6期8卷 371-376页

作者： benjamin fong chao Institure of Earth Sciences Academia Sinica Taipei Taiwan China

Earth＇s Coriolis force profoundly alters the eigen frequencies, eigen functions, and excitation of rotational normal modes. Some rotational modes of the solid mantle-fluid outer core-solid inner core Earth system are confirmed observationally and some remain elusive. Here we bring together from literature assertions about an excited resonance system in terms of the Green＇s function and temporal convolution. We raise caveats against taking the face values of the oscillational motion which have been ＂masqueraded＂ by the convolution, necessitating deconvolution for retrieving the excitation function which reflects the true variability. Lastly we exemplify successful applications of the deconvolution in estimating resonance complex frequencies.

关键词： Rotational modes Resonance Excitation Convolution Deconvolution

Improving Solution of Euler Equations by a Gas-Kinetic BGK Method

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西北工业大学学报 2009年第1期27卷 1-5页

作者： Liu, Ya Gao, chao Liu, f. National Key Laboratory of Aerodynamic Design and Research Northwestern Polytechnical University Xi'an 710072 China Department of Mechanical and Aerospace Engineering University of California Irvine CA 92697-3975 United States

*** well known JST(Jameson-Schmidt-Turkel) scheme requires the use of a dissipation *** propose using gas-kinetic BGK(Bhatnagar-Gross-Krook) method,which is based on the more fundamental Boltzmann equation,in order to obviate the use of dissipation term and obtain,we believe,an improved *** 1 deals essentially with three things:(1) as analytical solution of molecular probability density function at the cell interface has been obtained by the Boltzmann equation with BGK model,we can compute the flux term by integrating the density function in the phase space;eqs.(8) and(11) require careful attention;(2) the integrations can be expressed as the moments of Maxwellian distribution with different limits according to the analytical solution;eqs.(9) and(10) require careful attention;(3) the discrete equation by finite volume method can be solved using the time marching *** are performed by the BGK method for the Sod′s shock tube problem and a two-dimensional shock reflection *** results are compared with those of the conventional JST scheme in figs.1 and *** BGK method provides better resolution of shock waves and other features of the flow fields.

关键词： Euler equations Boltzmann equation gas-kinetic BGK(Bhatnagar-Gross-Krook) scheme JST(Jameson-Schmidt-Turkel) scheme shock tube shock reflection

Immunobiology and immunotherapy of HCC:spotlight on innate and innate-like immune cells

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Cellular & Molecular Immunology 2021年第1期18卷 112-127页

作者： benjamin Ruf Bernd Heinrich Tim f.Greten Gastrointestinal Malignancy Section Thoracic and Gastrointestinal Malignancies BranchCentre for Cancer ResearchNational Cancer InstituteNational Institutes of HealthBethesdaMD 20892USA NCI CCR Liver Cancer Program National Institutes of HealthBethesdaMD 20892USA

Immune-based therapies such as immune checkpoint inhibitors have revolutionized the systemic treatment of various cancer *** therapeutic application of monoclonal antibodies targeting inhibitory pathways such as programmed cell death-1(PD-1)/programmed cell death ligand 1(PD-L1)and CTLA-4 to cells of the adaptive immune system has recently been shown to generate meaningful improvement in the clinical outcome of hepatocellular carcinoma(HCC).Nevertheless,current immunotherapeutic approaches induce durable responses in only a subset of HCC *** immunologic mechanisms such as chronic inflammation due to chronic viral hepatitis or alcoholic and nonalcoholic fatty liver disease play a crucial role in the initiation,development,and progression of HCC,it is important to understand the underlying mechanisms shaping the unique tumor microenvironment of liver *** liver is an immunologic organ with large populations of innate and innate-like immune cells and is exposed to bacterial,viral,and fungal antigens through the gut-liver ***,we summarize and highlight the role of these cells in liver cancer and propose strategies to therapeutically target *** also discuss current immunotherapeutic strategies in HCC and outline recent advances in our understanding of how the therapeutic potential of these agents might be enhanced.

关键词： HCC immunotherapy innate immunity tumor microenvironment

The Nature-Based Ecological Engineering Paradigm: Symbiosis, Coupling, and Coordination

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Engineering 2022年第12期19卷 14-21页

作者： Xiahui Wang Jinnan Wang Bo Wang benjamin Burkhard Lulu Che chao Dai Lijie Zheng Institute of Ecological Conservation and Restoration Chinese Academy of Environmental PlanningBeijing 100012China Joint Laboratory of Ecological Products and Natural Capital Beijing 100012China Center of Biodiversity and Nature Reserves Chinese Academy of Environmental PlanningBeijing 100012China Institute of Physical Geography and Landscape Ecology Leibniz University HannoverHannover LS 30167Germany

*** We are currently facing three major ecological threats on a global scale:biodiversity loss,climate change,and environmental pollution *** degradation of terrestrial and marine ecosystems poses a major risk to human survival and development,brings serious impacts to the wellbeing of 3.2 billion people,and causes the loss of about 10%of the annual global gross domestic product(GDP)[1,2].Meanwhile,the coronavirus disease 2019(COVID-19)epidemic is still spreading rapidly throughout the world,showing that the present relationship between humans and nature is *** is necessary to protect nature so as to maintain the self-resilience of ecosystems.

关键词： Ecological ecosystems maintain

Trace-element geochemistry and S–O isotopes in the fluorite-barite mineralization of Merguechoum,Moroccan eastern Meseta:insights into ore genesis to the Pangea rifting

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Acta Geochimica 2023年第3期42卷 435-452页

作者： Mohammed Cherai Larbi Rddad fouad Talbi benjamin f.Walter faculte´des Sciences Laboratoire de GeosciencesGeo-Environnement et Prospection Miniere et HydriqueBP 71760000 OujdaMaroc Earth and Planetary Science Division Physical Science DepartmentKingsborough Community College of the City University of New York(CUNY)2001 Oriental BoulevardBrooklynNY 11235–2398USA Chair of Economic Geology and Geochemistry Karlsruhe Institute of Technology(KIT)Adenauerring 20B76131 KarlsruheGermany Laboratory for Environmental and Raw Material Analyses(LERA) Adenauerring 20B76131 KarlsruheGermany

The Merguechoum fluorite-barite mineralization,located in the Eastern Meseta of Morocco,is hosted in the Late Hercynian *** ore consists of fine crystals of fluorite 1,massive barite 1,euhedral crystals of fluorite 2,and barite 2 with calcite and minor quartz and *** Merguechoum ore deposits have never been *** study was the first contribution that studied the genesis of fluorite and *** ore occurs as dissemination within granite intrusion and also fills the NE-SWtrending meter-sized fractures and *** values of the total Rare Earth Elements and Yttrium(REY)and the ratios of LREY/HREY,Y/Ho,Tb/Ca,and Tb/La indicate that the Merguechoum fluorite precipitated from hydrothermal fluids,likely basinal brines,which interacted with the Hercynian *** REY data indicate that the ore-forming fluids of the early stage have intensely interacted with the Hercynian granite compared to those of the late ore *** gradual decrease in the europium(Eu/Eu^(*)),yttrium(Y/Y^(*)),and cerium(Ce/Ce^(*))anomalies and a low concentration ofΣREY observed in the second ore stage compared to the first ore stage suggest an increase in p H and fO_(2)and by inference a decrease in temperature during the evolution of the hydrothermal *** evolution could be explained by fluid mixing between the ascending basinal hydrothermal fluids and the diluted sulfate-rich meteoric water barite separates from selected samples reveal that the dissolved sulfates(SO_(4)^(2-))were derived from Permian–Triassic sulfates and/or coeval poreseawater *** proposed fluid mixing triggered the precipitation of an early-stage f-Ba assemblage followed by the second-stage f-Ba *** fieldwork,REY inventories,and isotope data point to the ore genesis during the Permian–Triassic extensional tectonic activity concerning the Pangea *** extensional tectonic environment is likely the driving force that mobilized a large amount of the ore

关键词： fluorite-barite veins Geochemistry of REY and trace elements O–S isotopes Late hercynian granite Pangea rifting Merguechoum Eastern Meseta of Moroccan

Compost Input Effect on Dryland Wheat and forage Yields and Soil Quality

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Pedosphere 2018年第3期28卷 451-462页

作者： francisco J. CALDERON Merle f. VIGIL Joseph benjamin United States Department of Agriculture-Agricultural Research Service (USDA-ARS) Central Great Plains Research Station Akron80720 CO( USA)

Organic agricultural systems rely on organic amendments to achieve crop fertility requirements, and weed control must be achieved without synthetic herbicides. Our objective was to determine the crop yield and soil quality as affected by a transition from grass to dryland organic agriculture in the Central Great Plains of North America. This study evaluated three beef feedlot compost(BfC)treatments in 2010–2015 following biennial application rates: 0(control), 22.9, and 108.7 t ha^(-1) on two dryland organic cropping systems: a wheat(Triticum aestivum)-fallow(Wf) rotation harvested for grain and a triticale(Triticosecale)/pea(Pisum sativum)-fallow(T/P-f) rotation harvested for forage. The triticale + pea biomass responded positively to the 108.7-t ha^(-1) BfC treatment,but not the 22.9-t ha^(-1) BfC treatment. The wheat biomass was not affected by BfC addition, but biomass N content *** feedlot compost input did not increase wheat grain yields, but had a positive effect on wheat grain Zn content. Soil total C and N contents increased with the rate of 108.7 t ha^(-1) BfC after three applications, but not with 22.9 t ha^(-1) BfC. Soil enzyme activities associated with N and C cycling responded positively to the 108.7-t ha^(-1) BfC treatment. Saturated salts were high in the soil receiving 108.7 t ha^(-1) of BfC, but did not affect crop yields. These results showed that BfC was effective in enhancing forage yields, wheat grain quality, and soil C and N, as well as specific microbial enzymes important for nutrient cycling. However, the large rates of BfC necessary to elicit these positive responses did not increase grain yields, and resulted in an excessive buildup of soil P.

关键词： organic agriculture soil C soil enzyme activity soil N pea triticale

控制方向未知的受限多智能体系统的预设时间模糊控制

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工程科学学报 2025年第1期47卷 121-129页

作者：李菲周超范利蓉王芳燕山大学理学院秦皇岛066004 河北农业大学海洋学院秦皇岛066003

综合考虑受控制方向未知、输入受限和状态时延影响的有领导者多智能体系统的编队控制问题,设计基于模糊逻辑系统的预设时间一致性控制策略.为了保证编队输出误差在预设时间内满足预定的约束范围要求,引入预设时间性能函数,构造Lyapunov-... 详细信息

综合考虑受控制方向未知、输入受限和状态时延影响的有领导者多智能体系统的编队控制问题,设计基于模糊逻辑系统的预设时间一致性控制策略.为了保证编队输出误差在预设时间内满足预定的约束范围要求,引入预设时间性能函数,构造Lyapunov-Krasovskii(L-K)泛函解决状态时延问题,将外界干扰和L-K泛函的导数中的部分项定义为未知非线性函数,并利用模糊逻辑系统对其进行估计,利用Nussbaum函数和均值定理分别处理控制方向未知和输入受限问题,基于以上设计,提出预设时间模糊控制策略,并通过Lyapunov稳定性理论,分析闭环系统的有界稳定性,数值对比仿真和两级化学反应器应用仿真说明控制方法的有效性.

关键词：多智能体系统状态时延输出误差约束输入受限控制方向未知

Modeling of miss-probability in content-centric networking

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Science China(Information Sciences) 2015年第7期58卷 187-199页

作者： HUANG Tao WANG GuoQing fANG chao YU f.Richard LIU YunJie State Key Laboratory of Networking and Switching Technology Beijing University of Posts and Telecommunications Department of Systems and Computer Engineering Carleton University

Content-Centric Networking(CCN), one of the most promising future Internet architectures, is a hot research topic because of its advantages of content delivery over the Internet. Based on the Least Recently Used(LRU) replacement policy in CCN, the closed-form expression of the miss-probability is first derived by considering the sequence of arriving requests under single cache scenario, and then extended to linear and binary tree topologies. Consequently, the virtual round trip time(VRTT) is determined to be influenced by cache capacity and link bandwidth. The simulation results show that the proposed miss-probability model accords with realistic CCN network conditions, being much better than the existing model.

关键词： in-network caching miss-probability least recently used request sequence content-centric net-working